Tiga Hal yang Harus Diketahui Mengenai Diabetes Terkontrol

Kebanyakan penderita diabetes (kencing manis) tidak mendengar apa yang telah diedukasikan oleh dokter mengenai hal penting apa saja yang berguna untuk pengontrolan diabetes mereka. Ada tiga hal penting yang harus diketahui dalam perawatan diabetes, yakni memonitor gula darah secara rutin, merencanakan mengkonsumsi makanan layak/tepat untuk diabetes, dan latihan (exercise). Penjelasan dari ketiganya ialah sebagai berikut:

Memonitor Gula Darah
Kadar gula darah harus dikontrol baik secara mandiri (dengan alat pengukur kadar gula darah) maupun datang ke tenaga medis. Kadar gula darah sebaiknya dikontrol secara teratur setiap satu atau dua minggu. Waspadai kadar gula darah di atas 140 mg/dl, hubungi dokter sesegera mungkin apabila kadar gula darah kita memang di atas angka itu.

Merencanakan Makanan yang Tepat
Pasien dengan diabetes pada dasarnya harus mencegah/mengurangi sedikit mungkin memakan-makanan yang berasa manis. Namun, untuk rekomendasi, benar-benar mencegah makanan manis adalah lebih baik. Selain itu, memakan/meminum apapun (terutama yang manis) dalam jumlah banyak apalagi dengan frekuensi sering juga tidak disarankan karena akan mengakibatkan kelebihan kadar gula darah yang dapat memicu terjadinya penyakit diabetes. Makanan yang tepat untuk penderita diabetes ialah nasi merah, sereal, nasi jagung, kacang-kacangan, sayur-sayuran, buah-buahan (yang terlalu manis tidak dianjurkan), daging, dan ikan. Semua jenis makanan itu harus "tepat jumlah" dalam artian tidak boleh berlebihan, secukupnya saja (atau sesuai rekomendasi dokter). Beras, baik dalam bentuk nasi maupun bubur juga harus dikurangi karena memiliki karbohidrat yang tinggi, yang dapat memicu peningkatan gula darah dalam tubuh. Mengenai minum, penderita diabetes sangat disarankan banyak minum air putih, tetapi sedikit minum susu (rendah lemak) dan yogurt.

Latihan (Olahraga)
Penderita diabetes, selain mempunyai riwayat memakan makanan berkadar gula tinggi, juga kerap memiliki riwayat jarang berolahraga/beraktivitas cukup untuk membakar timbunan energi berlebih yang bersemayam dalam tubuh. Oleh karena itu, beraktivitas fisik secara teratur seperti jalan santai ataupun jogging sangat disarankan untuk penderita diabetes. Olahraga yang berat tidak direkomendasikan apalagi untuk penderita diabetes yang telah mempunyai komplikasi penyakit lain.

Skor Alvarado (Untuk Keperluan Diagnosis Apendisitis Akut)

Skor Alvarado adalah suatu sistem pen-skor-an yang digunakan untuk menetapkan ada atau tidaknya diagnosis appendisitis akut (penyakit usus buntu). Skor Alvarado merupakan delapan komponen skor yang terdiri dari enam komponen klinik dan dua komponen laboratorium dengan total skor maksimal 10.

Dibawah adalah tabel skor Alvarado:

Tabel Skor Alvarado	Skor
Gejala Klinis ·         Nyeri abdominal pindah ke fossa iliaka kanan ·         Nafsu makan menurun ·         Mual dan atau muntah	1 1 1
Tanda Klinis ·         Nyeri lepas ·         Nyeri tekan fossa iliaka kanan ·         Demam (suhu > 37,2⁰ C)	1 2 1
Pemeriksaan Laboratoris ·         Leukositosis (leukosit > 10.000/ml) ·         Shift to the left  (neutrofil > 75%)	2 1
TOTAL	20

Interpretasi:
Skor 7-10 = Apendisitis akut
Skor 5-6 = Curiga apendisitis akut
Skor 1-4 = Bukan apendisitis akut

Tips Membina Hubungan dengan Pasien

Seorang ibu, istri seorang buruh tani dengan pakaian lusuh, membawa seorang anak perempuannya yang berumur 23 bulan ke dokter karena anak tersebut menderita panas dan diare selama 5 hari. Ibu tersebut mengatakan bahwa sangat kecewa dengan pelayanan yang diberikan oleh dokter tersebut. Menurut si ibu, dokter tersebut tidak ramah, tidak menjawab pertanyaannya dan tidak menjelaskan tentang penyakit anaknya secara jelas serta mengenai obat yang diberikan, meskipun ia ditarik bayaran yang cukup tinggi.
Berdasarkan masalah itu tentunya seorang dokter dapat memberikan pelayanan yang baik kepada pasiennya. Oleh karena itu seorang dokter harus terlebih dahulu mengetahui fungsi utama seorang dokter, yaitu:

• menerapkan peraturan umum/khusus kepada pasien
• membina interaksi dengan pasien secara luas dari membaur atau terbatas
• melibatkan emosi atau netral
• mengutamakan kepentingan diri atau bersama
• memandang manusia berdasar kualitas atau prestasinya.

Adapun tugas utama seorang dokter ialah Menerapakan pengetahuannya tentang pengobatan penyakit terhadap pasien pada umumnya. Maka Dokter yang bijak:

• mendahulukan komunikasi secara efektif dengan pasien
• mendengarkan keluhan pasien
• menjawab pertanyaan dan menjelaskan situasi pasien
• memberi nasihat cukup sehingga pasien pun
• menjelaskan hal-hal yang perlu diketahui pasien tentang penyakitnya

Selain itu faktor yang mempengaruhi komunikasi dokter dengan pasien:

• suka berkata dan bersikap kasar
• kelelahan akibat kerja sehingga kehilangan minat menolong pasien
• masalah pribadi yang membebani diri
• menderita gangguan jiwa
• terlalu yakin melakukan sesuatu di luar kompetensi
• tdak percaya diri
• berkepentingan ganda

Seorang dokter harus bersikap idealis dan tidak boleh bersaing dengan teman sejawat atau mereklamekan diri (orientasi kelompok). Sukses seorang dokter di antaranya ditentukan oleh unusr-unsur pribadi dan kemampuan dokter bersikap dengan pasiennya. Misalnya, dokter harus melayani pasien suka maupun tidak suka, menggunakan bahasa yang mudah dimengerti, memberi nasihat tidak boleh menghakimi, berbicara terbuka, mengajak pasien mengubah perilakunya dengan mengajak pasien menerapkan pola hidup sehat, dan menghargai pasien. Untuk itu, seorang dokter harus memperhatikan latar belakang pasien dan lingkungannya.
Keterampilan komunikasi yang perlu dikembangkan seorang dokter:

C = Comfort
A = Acceptance
R = Responsiveness
E = Empathy

Keterampilan komunikasi dan empati ini adalah pilar menerapkan etika dokter.
Hubungan seorang dokter dan pasiennya ditentukan oleh seberapa jauh dokter bersedia terlibat dalam situasi emosional pasien dan menjga jarak dengan persoalan pasien.
Maka seorang Pasien juga perlu menjadi pasien yang pintar bagi dokternya, antara lain :

• memakai pakaian yang memudahkan dokter memeriksa
• memberitahukan keluhan secara lengkap
• sebaiknya bertanya dan mengetahui obat yang diberikan

Harapan masyarakat kepada dokter :

• mampu mengobati pasien dengan teliti dan terampil
• mampu mendengarkan, menghormati pendapat pasien, berperilaku santun, dan penuh pertimbangan serta memberi nasehat tanpa menggurui
• mampu menyimpan rahasia, jujur, dan mempunyai integritas serta tetap memberikan asupan meski ilmu kedokteran tidak mampu menyembuhkan penyakitnya
• mampu mempertahankan hubungan yang luwes sehingga pasien mendapat penjelasan lengkap dan dilibatkan dalam keputusan tentang asuhan

Dengan menaati segala peraturan diatas, maka diharapkan hubungan dokter dengan pasien akan berlangsung sangat baik dan mempermudah kesembuhan si pasien dengan kekuatan sugesti.

Contoh Kasus: Copy-Paste dari: http://goe2n.wordpress.com/2007/11/05/tips-membina-hubungan-dengan-pasien/

Secarik Fakta Tentang Penularan HIV/AIDS

HIV adalah virus penyebab AIDS (Acquired Immune Deficiency Syndrome). Virus tersebut menyerang sistem kekebalan tubuh, sehingga menyebabkan orang yang telah terinfeksi menjadi sangat rentan terhadap berbagai penyakit yang mengancam hidupnya.

Ada beberapa fakta yang penulis rangkum dari sebuah poster di rumah sakit tempat penulis menuntut ilmu. Pada poster itu, berisi beberapa fakta yang dipromosikan oleh berbagai lembaga kesehatan termasuk DEPKES RI. Adapun fakta tersebut ialah:

HIV/AIDS menular melalui:

• Penggunaan satu jarum suntik secara bergantian/menggunakan jarum bekas. Berbagi dan menggunakan kembali jarum suntik yang mengandung darah yang terkontaminasi oleh virus HIV merupakan risiko utama terkena penyakit HIV/AIDS.
  
• Hubungan seks berganti-gantian pasangan tanpa menggunakan pengaman/kondom (tidak disarankan hubungan seks dengan cara apapun sebelum terikat pernikahan). Penularan HIV secara seksual terjadi ketika ada kontak antara pengeluaran cairan vagina wanita (yang terinfeksi) dengan alat kelamin atau mukosa mulut si pria, begitupun sebaliknya. Hubungan seksual tanpa pelindung lebih berisiko daripada hubungan seksual dengan pelindung, dan risiko hubungan seks anal lebih besar daripada risiko hubungan seks biasa dan seks oral.
• Dari ibu ke anak melalui kelahiran. Penularan HIV dari ibu ke anak dapat terjadi melalui rahim (in utero) selama masa perinatal, yaitu minggu-minggu terakhir kehamilan, serta saat persalinan, yaitu ketika bayi kontak langsung dengan jalan lahir. 
• Dari ibu ke anak melalui ASI. ASI pada penderita HIV/AIDS ialah ASI yang terkontaminasi virus HIV, sehingga penularan HIV melalui ASI dari ibu ke anak sangat mungkin terjadi.

HIV/AIDS tidak menular melalui:

• Nyamuk/jenis serangga lain. Tidak ada jenis nyamuk yang membawa virus HIV di dalam tubuhnya.
• Bekerja bersama orang yang terinfeksi HIV. Bekerja bersama penderita HIV/AIDS pada dasarnya merupakan hal yang tidak perlu ditakutkan, asalkan selalu berhati-hati pada setiap kemungkinan penularan melalui darah (khususnya pada pekerja kasar/buruh di mana bahaya mekanik lebih rentan).
• Berpegangan tangan/saling berpelukan dengan orang HIV. Bersalaman dan berpelukan dalam artian yang lebih umum. Intinya, selama tidak ada kontak dengan darah penderita, bersentuhan ialah aman.
• Hubungan seks dengan menggunakan kondom (tidak disarankan hubungan seks dengan cara apapun sebelum terikat pernikahan). Hubungan seksual dengan pelindung berisiko kecil untuk tertularnya HIV/AIDS.
• Berbagi makanan/menggunakan peralatan makan bersama. Air liur bukan media penularan HIV.
• Menggunakan toilet bersama. Feses (kotoran) juga bukan merupakan media penularan HIV.
• Terpapar batuk/bersin orang yang terinfeksi HIV.  Telah disinggung bahwa air liur/percikan air ketika bersin bukan media penularan HIV

Orang-orang dengan HIV/AIDS (ODHA) tidak ada bedanya dengan kita. Mereka juga mempunyai hak dan kesempatan yang sama dengan orang lain dalam berkreasi tanpa dibatasi oleh pemisah antar golongan (golongan tanpa atau dengan HIV/AIDS).

Lama Tidur yang Kita Butuhkan Berdasarkan Usia Kita

 Tidur merupakan fenomena alami yang dikategorikan sebagai berkurangnya atau hilangnya kesadaran, kinerja otot, dan aktivitas sensorik. Ketika kita tidur, kita akan kehilangan reaksi terhadap berbagai stimulus (rangsangan), apalagi stimulus itu bersifat ringan. Meskipu demikian, tidur merupakan aktivitas yang amat penting untuk peremajaan berbagai sistem pada tubuh kita, seperti sistem imun, muskuloskeletal, dan saraf.

Sepanjang kehidupan, seiring dengan perubahan tumbuh kembang kita, pola tidur kita pun kian berubah. Pola tidur setiap golongan usia secara umum berbeda-beda. Golongan usia dibagi menjadi tujuh kategori berdasarkan rata-rata lama tidur yang dibutuhkan. Kelompok-kelompok usia itu ialah kelompok usia 0-2 bulan, 3-12 bulan,1-3 tahun, 3-5 tahun, 5-12 tahun, 12-18 tahun, dan di atas 18 tahun.

Setelah kita lahir, sampai kira-kira berumur 2 bulan, kita tidur selama 12-18 jam sehari. Ketika kita berumur 3 bulan hingga kita berumur 1 tahun, rata-rata lama tidur kita menurun dari 12-18 jam menjadi 14-15 jam perhari. Ketika kita beranjak ke usia 1-3 tahun, rata-rata lama tidur kita menjadi 12-14 jam perhari. Rata-rata lama tidur terus menurun saat kita mencapai usia prasekolah (3-5 tahun) yaitu dari 12-14 jam menjadi 11-13 jam perhari. Di masa usia sekolah (5-12 tahun), rata-rata lama tidur kita menurun menjadi 10-11 jam perhari, begitupun saat kita berusia 12-18 tahun, rata-rata lama tidur kita pun menurun, yaitu selama 8,5-10 jam perhari. Selanjutnya, ketika kita beranjak ke usia dewasa (di atas 18 tahun dst), rata-rata lama tidur kita hanya 7,5 sampai 9 jam perharinya.

Dengan kata lain, semakin bertambahnya usia kita, semakin turun rata-rata lama tidur kita. Sebaliknya, semakin muda usia kita, rata-rata lama tidur kita semakin tinggi. Artinya, tidur memang kita perlukan di kala kita masih berusia muda (0 sampai beberapa tahun pertama kehidupan kita), yang mana, ketika itu tidur berguna untuk pertumbuhan tubuh kita.

Kebutuhan akan tidur di kala kita beranjak dewasa, telah beralih kepada kualitas di saat kita tidur, meskipun lama tidur tetap berpengaruh. Tidur dengan tenang (tanpa gangguan) memiliki peran esensial bagi berbagai aspek kehidupan kita, misalnya untuk penyembuhan luka, pemulihan energi, dan lain-lain.

Setidaknya, dengan berpedoman pada rata-rata lama tidur (dengan mempertimbangkan kualitas tidur), kita dapat mencegah berbagai penyakit yang mungkin terjadi ketika tubuh kita tidak dalam keadaan prima.

Lima Alasan Mengapa Wanita Terkena Kanker Payudara

1. Lingkungan Sekitar. Lingkungan merupakan salah satu alasan mengapa wanita terkena kanker payudara. Salah satu faktor lingkungan yang dimaksud adalah radiasi. Penggunaan radiasi untuk pengobatan penyakit tertentu meningkatkan risiko terjadinya kanker payudara. Contoh lain ialah pestisida. Pestisida yang digunakan dalam pertanian dapat masuk ke dalam tubuh seseorang melalui produk pertanian yang dikonsumsi.
2. Diet (pola makan) Tidak Seimbang. Diet di sini berarti pola makan, bukan berarti diet untuk kegemukan. Diet mungkin merupakan faktor lain yang menyebabkan kanker payudara. Jika diet seseorang mengandung terlalu banyak lemak, maka diet semacam inilah yang membawa kepada terjadinya kanker payudara. Seorang wanita seharusnya makan-makanan yang seimbang sesuai rujukan para ahli gizi atau majalah-majalah kesehatan lain. Telah banyak studi yang menyebutkan bahwa makanan, baik kuantitas maupun kualitas yang tidak sesuai berkaitan dengan berbagai macam penyakit, terutama kanker. Dalam artikel kali ini, penulis tidak menyebutkan apa saja makanan yang sesuai atau seimbang, mungkin lain kali akan dibicarakan. 
3. Alkohol. Seorang wanita peminum alkohol lebih banyak menderita kanker dibanding yang bukan peminum alkohol. Hal ini sejalan dengan ungkapan banyak pakar bahwa alkohol meningkatkan risiko terjadinya kanker payudara. Kebiasaan meminum alkohol meningkatkan risiko hingga beberapa kali untuk terkenanya kanker payudara.
4. Gen dan Keturunan. Banyak penderita kanker payudara mempunyai seorang ibu yang juga penderita kanker payudara. Peneliti menyebutkan 10% penderita kanker payudara mempunyai riwayat keluarga dengan kanker payudara pula. Sebuah gen yang disebut BRCA1 diduga merupakan gen yang diturunkan dari seorang ibu ke anak perempuannya, yang berkaitan dengan kejadian kanker payudara. Secara umum, gen tersebut tidak menyebabkan kanker payudara, tetapi ketika gen itu bermutasi, barulah terjadi kanker payudara. 
5. Hormon. Risiko kanker payudara meningkat seiring dengan terjadinya beberapa metabolisme hormonal pada seorang wanita. Sebagai cotoh metabolisme hormonal ialah ketika wanita terlalu dini mengalami menstruasi, terlalu tua mengalami mens terakhir (menopause > 51 tahun), terlalu tua memiliki anak (melahirkan anak pertama saat usia 30 tahun), tidak mempunyai anak, serta telah memiliki riwayat penyakit kanker payudara tetapi tidak dikontrol dengan terapi hormon.    

Sumber bacaan: medsavailable.com

Fakta Tentang Sindroma Radiasi Akut

Sindroma Radiasi Akut (Acute Radiation Syndrome/ARS) ialah kumpulan gejala yang terjadi ketika seluruh atau hampir seluruh tubuh terpapar radiasi dosis tinggi, biasanya paparan bersifat akut (periode singkat).

ARS pernah terjadi pada penduduk di Hiroshima dan Nagasaki sekitar tahun 1940-an setelah peristiwa pengeboman terhadap kedua kota berpenduduk itu. 

Seseorang yang terpapar radiasi dikatakan terkena ARS hanya jika:

• Radiasi dalam dosis/tingkatan yang tinggi (dosis dari prosedur medis seperti Chest X-Ray berpengaruh amat rendah terhadap terjadinya ARS, sedangkan prosedur lain seperti terapi radiasi untuk pengobatan kanker berpengaruh cukup tinggi terhadap terjadinya ARS).
• Partikel-partikel radiasi menembus organ dalam, dalam artian radiasi terpenetrasi ke dalam tubuh.
• Radiasi terpapar secara akut dan mengenai seluruh/sebagian besar permukaan tubuh.

Gejala utama dari sindroma ARS ini adalah mual, muntah, dan diare. Gejala-gejala ini dapat terjadi beberapa menit bahkan berhari-hari setelah terpapar radiasi, dan bersifat hilang dan timbul, yang berarti seseorang sewaktu-waktu tidak menampakkan gejala apapun, tetapi di waktu mendatang gejala perlahan-lahan timbul kembali bahkan disertai gejala tambahan seperti hilang nafsu makan, pusing, demam, sampai kejang dan koma. Bila telah mencapai tahap gawat, penyakit ini biasanya terjadi selama beberapa bulan tanpa "hilang dan timbul".

Seseorang dengan ARS juga terkena berbagai kerusakan kulit. Kerusakan dapat berupa bengkak, gatal, kemerahan disertai sensasi terbakar yang dapat terjadi beberapa jam setelah terpapar.

Penderita ARS, kebanyakan meninggal beberapa bulan setelah terpapar. Penyebab kematian terbanyak ialah akibat kerusakan sumsum tulang (penghasil sel-sel darah), yang menyebabkan beberapa komponen darah seperti sel darah putih, trombosit, dan sel darah merah tidak terbentuk sehingga kerentanan terhadap perdarahan dan infeksi kian tinggi.

Informasi diperoleh dari: http://www.bt.cdc.gov/ars.asp

Bagaimana Lemak Tubuh Mempengaruhi Kinerja Otak Kita?

Kebanyakan orang tidak mengetahui berbagai masalah pada tubuh akibat kelebihan lemak. Sebagian besar orang mengetahui bahwa lemak pada tubuh hanya mempengaruhi penampilan. Namun, masalah yang sebenarnya ada bukan hanya mengenai penampilan, melainkan juga masalah kesehatan.

Tubuh yang overweight (gemuk) berkaitan dengan berbagai masalah kesehatan, seperti artritis, penyakit jantung, diabetes, kolesterol tinggi, sleep apnea (tidur mendengkur), perlemakan pada hati, asma, hipertensi, penyakit batu empedu, gangguan mood, depresi, dan kelelahan, yang kesemuanya mempengaruhi kualitas hidup kita.

Untuk masalah kegemukan ini, banyak peneliti telah menemukan bahwa kegemukan banyak berkaitan dengan berbagai masalah pada organ-organ penting tubuh, salah satunya ialah masalah pada otak. Mereka menemukan bahwa meningkatnya jumlah lemak pada tubuh hingga bermanifestasikan kegemukan dapat mempercepat penyusutan (degenerasi) pada jaringan otak yang berakibat pada masalah kognitif seperti demensia alzheimer's (pikun akibat degenerasi otak). Mereka juga melaporkan bahwa kegemukan meningkatkan risiko gangguan memori, gangguan sensoris dan penglihatan, inatensi (berkurangnya perhatian), gangguan bicara, dan gangguan problem solving (pemecahan masalah).

Sebagai bagian dari penelitian, 94 orang usila (usia lanjut) yang tidak memiliki demensia atau gangguan kognitif lainnya diteliti dan di-follow up selama lima tahun. Hasil yang ditemukan dari studi ini ialah bahwa otak usila yang memiliki kelebihan berat badan tampak delapan tahun lebih tua dibandingkan otak usila yang tidak mengalami kelebihan berat badan. Selain itu, penampilan usila yang kegemukan terlihat 16 tahun lebih tua bila dibandingkan dengan usila yang lebih ramping. Secara teori, orang dengan indeks massa tubuh yang lebih besar memiliki otak yang lebih kecil karena mereka memiliki jaringan otak yang lebih kecil. Sebagian besar dari jaringan otak yang hilang berada di lobus frontal dan temporal, yang penting untuk perencanaan dan memori.

Secara dini, untuk sementara belum bisa dipastikan apakah benar kegemukan secara langsung menghantarkan pada terjadinya demensia, tetapi secara tidak langsung, jaringan otak yang lebih kecil pada orang-orang kegemukan merupakan indikasi proses rusaknya jaringan otak tersebut, dan ini berhubungan dengan risiko terjadinya demensia alzheimer's.

Peneliti mengatakan bahwa kegemukan dapat menyebabkan degenerasi otak karena terhambatnya aliran darah ke otak (sebagai akibat dari penyempitan pembuluh darah), sehingga sel-sel otak kekurangan suplai darah yang mengandung oksigen.

Translate:

Most people do not know the various problems due to excess body fat. Most people know that fat in the body only affects the appearance. However, the real problem is not just about appearance, but also health problems.

The body is overweight (fat) associated with various health problems, such as arthritis, heart disease, diabetes, high cholesterol, sleep apnea (snoring), fatty liver, asthma, hypertension, gallstone disease, mood disorders, depression, and fatigue, all of which affect our quality of life.

For this obesity problem, many researchers have found that obesity is more related to various problems in vital organs of the body, one of which is a problem in the brain. They found that increasing the amount of fat in the body until bermanifestasikan overweight can accelerate the depreciation (degeneration) in brain tissue that results in cognitive problems such as Alzheimer's dementia (dementia due to degeneration of the brain). They also reported that obesity increases the risk of memory impairment, sensory disturbances and vision, inatensi (less attention), speech disorders, and impaired problem solving (problem solving).

As part of the study, 94 elderly people (elderly) who do not have dementia or other cognitive disorders were examined and followed-up for five years. The results found from this study is that brain elderly who are overweight look eight years older than elderly brains are not overweight. In addition, elderly people who are overweight appearance looks 16 years older than the more slender elderly. In theory, people with body mass index greater have smaller brains because they have smaller brain tissue. Most of the missing brain tissue in frontal and temporal lobes, which are important for planning and memory.

Early, for while not yet certain whether obesity is directly deliver on the occurrence of dementia, but indirectly, brain tissue is smaller in people being overweight is an indication of the damage to brain tissue, and is associated with risk of dementia Alzheimer's.

Researchers say that obesity can cause degeneration of the brain due to blockage of blood flow to the brain (as a result of the narrowing of blood vessels), so that brain cells lack of blood supply that contains oxygen.

Kelainan Tulang Kongenital (Sejak Lahir)

Ada beberapa kelainan organ tubuh yang didapat sejak lahir, salah satunya ialah kelainan bawaan (kongenital) pada tulang.

Adapun beberapa kelainan bawaan tersebut yakni:

Congenital Talipes Equino Varus (CTEV)
Ialah deformitas umum dimana kaki berubah/bengkok dari keadaan atau posisi normal. Lebih detail, CTEV ialah deformitas forefoot adduksi dan supinasi melalui sendi midtarsal, tumit varus pada subtalar, equinus pada ankle dan deviasi medial seluruh kaki dalam hubungan dengan lutut (salter).

Metatarsus Primus Varus
Mencondongnya tulang metatarsal pertama ke arah garis tengah tubuh, sehingga menghasilkan sudut 20 derajat atau lebih antara metatarsal pertama dan kedua.

Genu Varum
Tulang paha (femur) dan betis (tibia) menjorok ke arah luar berbentuk busur.

Congenital Constriction Band (Ring)
Kelainan bawaan pada pergelangan ataupun bagian ekstemitas (tangan atau kaki) yang bermanifestasi seperti cincin.

Habitual Patella Dislocation
Kelainan bawaan pada letak patela (tempurung lutut) di mana tidak berada pada tempat yang benar.

Sindaktili
Adalah kelainan jari tangan berupa pelekatan dua jari atau lebih.

Polidaktili
Adalah kelainan pertumbuhan jari sehingga jumlah jari pada tangan atau kaki lebih dari lima.

Sebenarnya masih banyak kelainan lain yang dapat ditemui di masyarakat ataupun rumah sakit. Namun, kelainan yang disebutkan dalam artikel kali ini merupakan kelainan yang paling sering terjadi di dunia klinik, khususnya di Indonesia.

Translate:

There are some defects in organs derived from birth, one of which is congenital abnormalities (congenital) in the bone.


As for some of these inherited disorders are:


Congenital talipes Equino Varus (CTEV)

Common deformity in which the foot is turned / bent of the state or the normal position. More details, CTEV is forefoot adduction and supination deformity through the midtarsal joints, the heel on the subtalar varus, equinus at the ankle and medial deviation of the foot in relation to the knee (Salter).


Metatarsus Primus Varus
Mencondongnya first metatarsal bone toward the midline of the body, resulting in angle 20 degrees or more between the first and second metatarsal.


Genu Varum
Thigh bone (femur) and leg (tibia) protrudes outward bow-shaped.



Congenital constriction band (Ring)
Congenital abnormalities of the wrist or the ekstemitas (hands or feet) which manifests as a ring.


Habitual patellar Dislocation
Congenital abnormalities in the location of the patella (knee cap) which is not in the right place.


Syndactyly
Is a disorder of the fingers sticking two fingers or more.


Polydactyly
Is abnormal growth of the fingers so that the number of fingers on the hands or feet for more than five.


Actually there are many other disorders that can be found in community or hospital. However, the abnormalities mentioned in this article are the most common disorders in the clinic, especially in Indonesia.

Tujuh M Fungsi Hati

Hati yang dimaksud dalam postingan kali ini bukanlah hati yang bermakna "Qalbu", melainkan hati dalam bidang medis, atau biasa disebut dengan hepar.

Hepar merupakan kelenjar terbesar pada tubuh dibungkus oleh jaringan ikat (Glisson’s Capsule), beratnya berkisar 1200-1600 gram dan menerima darah 1500 ml permenit, serta mempunyai fungsi yang sangat banyak.

Adapun fungsi hepar, saya rangkum menjadi tujuh "M" fungsi hepar, yaitu:

Pertama. Mengatur:

• Mengatur jumlah karbohidrat; hati menjaga agar kadar glukosa darah tidak jauh dari 90 mg/dl
• Mengatur keseimbangan lemak
• Mengatur keseimbangan asam amino, asam lemak, trigliserida, dan kolesterol 
• Mengatur sirkulasi hormon

Kedua. Memproduksi dan atau Mensekresi:

• Memproduksi dan mensekresi empedu
• Memproduksi protein plasma

Ketiga. Membersihkan:

• Membersihkan sisa produk, amonia, ureum, toksin, dan sisa obat.
• Membersihkan antibodi residu (sisa)

Keempat. Memakan:

• Memakan antigen (dilakukan oleh sel-sel hepar)
• Memakan (memfagosit) mifroorganisme

Kelima. Menyimpan:

• Menyimpan vitamin larut lemak (Vitamin A, D, E, K) dan vitamin B12
• Menyimpan mineral

Keenam. Memproses:

• Memproses emulsi lemak (emulsifikasi lemak)

Ketujuh. Menghentikan:

• Menghentikan kerja obat (inaktivasi obat).

Translate:

Heart is referred to in this post is not a heart with meaning "Qalbu", but caution in the medical field, or commonly called the liver.


The liver is the largest gland in the body is wrapped by connective tissue (Glisson's Capsule), weight ranged from 1200 to 1600 grams and receive 1500 ml of blood per minute, and has a function very much.


As for liver function, I summarized into seven "M" liver function, namely:

First. Set:

* Set the number of carbohydrates, the liver keeps blood glucose levels are not far from the 90 mg / dl
* Set the fat balance
* Set the balance of amino acids, fatty acids, triglycerides, and cholesterol
* Set the circulation of hormones

Second. Producing or secreting:

* To produce and secrete bile
* Producing plasma proteins

Third. Clean:

* Clean the remaining product, ammonia, urea, toxins, and the rest of the drug.
* Clean the antibody residue (remainder)

Fourth. Eating:

* Eating antigens (carried by the cells of the liver)
* Consumed (memfagosit) mifroorganisme


Fifth. Saving:

* Save the fat-soluble vitamins (Vitamins A, D, E, K) and vitamin B12
* Storing minerals

Sixth. Processing:

* Processing of fat emulsion (emulsification of fat)

Seventh. Stops:

* Stopping the drugs work (drug inactivation).

Empat Manuver Leopold (Pemeriksaan ANC Kehamilan)

 Salah satu pemeriksaan yang dilakukan saat Ante Natal Care adalah pemeriksaan Leopold. Pemeriksaan ini terdiri dari 4 tindakan yang masing-masing dilakukan untuk mengetahui presentasi (kedudukan) bagian tubuh janin dalam uterus (rahim). Empat pemeriksaan Leopold tersebut adalah:

Leopold I
Bertujuan untuk menentukan usia kehamilan dan juga untuk mengetahui bagian janin apa yang terdapat di fundus uteri (bagian atas perut ibu).


Teknik pemeriksaan

• Pemeriksa menghadap ke kepala pasien, gunakan ujung jari kedua tangan untuk meraba fundus.

 Mengetahui bagian janin apa yang terdapat di fundus uteri

• Apabila kepala janin teraba di bagian fundus, yang akan teraba adalah keras,bundar dan melenting (seperti mudah digerakkan).
• Apabila bokong janin teraba di bagian fundus, yang akan terasa adalah lunak, kurang bundar, dan kurang melenting.
• Fundus kosong apabila posisi janin melintang pada rahim.

Menentukan usia kehamilan

• Pada usia kehamilan 12 minggu, fundus dapat teraba 1-2 jari di atas simpisis. 
• Pada usia kehamilan 16 minggu, fundus dapat teraba di antara simpisis dan pusat.
• Pada usia kehamilan 20 minggu, fundus dapat teraba 3 jari di bawah pusat. 
• Pada usia kehamilan 24 minggu, fundus dapat teraba tepat di pusat.
• Pada usia kehamilan 28 minggu, fundus dapat teraba 3 jari di atas pusat.
• Pada usia kehamilan 32 minggu, fundus dapat teraba di pertengahan antara prosesus xipoideus dan pusat.
• Pada usia kehamilan 36 minggu, fundus dapat teraba 3 jari di bawah prosesus xipoideus.
• Pada usia kehamilan 40 minggu, fundus dapat teraba di pertengahan antara prosesus xipoideus dan pusat. (Lakukan konfirmasi dengan wawancara dengan pasien untuk membedakan dengan usia kehamilan 32 minggu).

Leopold II
Bertujuan untuk menentukan di mana letak punggung ataupun  kaki janin pada kedua sisi perut ibu.

Teknik pemeriksaan

• menghadap ke kepala pasien, letakkan kedua tangan pada kedua sisi perut ibu, raba (palpasi) kedua bagian sisi perut ibu.

Menentukan di mana letak punggung ataupun  kaki janin pada kedua sisi perut ibu

• bagian punggung akan teraba jelas, rata, cembung, kaku/tidak dapat digerakkan.
• bagian-bagian kecil (tangan dan kaki) akan teraba kecil, bentuk/posisi tidak jelas dan menonjol, kemungkinan teraba gerakan kaki janin secara aktif maupun pasif.

Leopold III
Bertujuan untuk menentukan bagian janin apa (kepala atau bokong) yang terdapat di bagian bawah perut ibu, serta apakah bagian janin tersebut sudah menyentuh pintu atas panggul.

Teknik pemeriksaan

• Pemeriksa hanya menggunakan satu tangan. (Lihat gambar!)
• Bagian yang teraba, bisa kepala, bisa juga bokong (Lihat Leopold I!)
• Cobalah apakah bagian yang teraba itu masih dapat digerakkan atau tidak. Apabila tidak dapat digoyangkan, maka janin sudah menyentuh pintu atas panggul.

Leopold IV
Bertujuan untuk mengkonfirmasi ulang bagian janin apa yang terdapat di bagian bawah perut ibu, serta untuk mengetahui seberapa jauh bagian bawah janin telah memasuki pintu atas panggul.

Teknik pemeriksaan

• pemeriksa menghadap kaki pasien
• dengan kedua tangan ditentukan bagian janin apa (bokongkah atau kepalakah?) yang terletak di bagian bawah perut ibu.

Mengetahui seberapa jauh bagian bawah janin telah memasuki pintu atas panggul

• Apabila konvergen (jari-jari kedua tangan bertemu), berarti baru sedikit janin memasuki pintu atas panggul. Apabila divergen (jarak antara kedua jari pemeriksa jauh), janin (kepala janin) telah banyak memasuki pintu atas panggul).

Translate:

One of the tests when Ante Natal Care is an examination of Leopold. This examination consists of 4 individual actions carried out to find a presentation (position) the body of the fetus in the uterus (womb). Four Leopold examination are:


Leopold I
Aiming to determine the gestational age and also to know what fetal part contained in the uterine fundus (the top of the mother's abdomen).


Technical inspection

* Examining the patient's head facing, use the tip of the fingers of both hands to palpate the fundus.

Knowing what the fetus contained in the fundus uteri

* If the fetal head palpable at the fundus, which will be felt is hard, round and bouncy (such as low effort).
* If the fetus is palpable in the posterior fundus, which will be felt is a soft, less rounded, and less bouncy.
* Fundus blank if the position of the fetus across the uterus.

Determine gestational age

* At 12 weeks gestation, the fundus can be palpated 1-2 fingers above simpisis.
* At 16 weeks gestation, the fundus can be palpated between simpisis and center.
* At 20 weeks gestation, the fundus could be felt 3 fingers below the center.
* At 24 weeks gestation, the fundus can be felt right in the center.
* At 28 weeks gestation, the fundus could be felt 3 fingers above the center.
* At 32 weeks gestation, the fundus can be palpated in the middle between the processus xipoideus and center.
* At 36 weeks gestation, the fundus could be felt 3 fingers below the processus xipoideus.
* At 40 weeks gestation, the fundus can be palpated in the middle between the processus xipoideus and center. (Do confirmation by interviews with patients to distinguish with gestational age 32 weeks).

Leopold II
Aiming to determine where the fetal back or legs on both sides of the mother's abdomen.

Technical inspection

* Facing the patient's head, put both hands on both sides of the mother's abdomen, touch (palpation) the two parts of the mother's abdomen.

Determine where the fetal back or leg on either side of the mother's abdomen

* The back will be felt clear, flat, convex, rigid / not be moved.
* Small parts (hands and feet) will be felt small, the shape / position is clear and prominent, palpable possibility of fetal leg movements actively or passively.


Leopold III
Aiming to determine what fetal part (head or buttocks) that sits at the bottom of the mother's abdomen, and whether the fetus has already touched the door of the pelvis.

Technical inspection

* Examining only using one hand. (See picture!)
* Part of palpable, can head, can also butt (See Leopold I!)
* Try whether a palpable part of it still can be moved or not. If that does not shaken, then the fetus has touched the door of the pelvis.


Leopold IV
Aiming to reconfirm what fetal part is at the bottom of the mother's abdomen, and to know how far the bottom of the fetuses had entered the door of the pelvis.

Technical inspection

* Examiner facing the patient's foot
* With two hands determined what parts of the fetus (bokongkah or kepalakah?) Located at the bottom of the mother's abdomen.

Knowing how far the bottom of the fetuses had entered the door of the pelvis

* If the convergent (both fingers meet the hand), meaning the fetus entered the door just slightly above the pelvis. If the divergent (the distance between the two examiners finger distance), fetal (fetal head) has a lot in the door of the pelvis).

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10 Benefits of Apple

Do you know apple ? of course, everybody know that. But do you know benefit of apple ?
Okay, you should read the article bellow to know what materials of apple inside and its effect to our body..
There are 10 benefits of apple for our health. Please check it out.

1. Alzheimer's Prevention
A study on mice at Cornell University found that the quercetin in apples may protect brain cells from the kind of free radical damage that may lead to Alzheimer's disease


2. Lower Cholesterol
The pectin in apples lowers LDL ("bad") cholesterol. People who eat two apples per day may lower their cholesterol by as much as 16 percent.


3. Breast Cancer Prevention
A Cornell University study found that rats who ate one apple per day reduced their risk of breast cancer by 17 percent. Rats fed three apples per day reduced their risk by 39 percent and those fed six apples per day reduced their risk by 44 percent.

4. Colon Cancer Prevention
One study found that rats fed an extract from apple skins had a 43 percent lower risk of colon cancer. Other research shows that the pectin in apples reduces the risk of colon cancer and helps maintain a healthy digestive tract

5. Lung Cancer Prevention
According to a study of 10,000 people, those who ate the most apples had a 50 percent lower risk of developing lung cancer. Researchers believe this is due to the high levels of the flavonoids quercetin and naringin in apples.

6. Liver Cancer Prevention
Research found that rats fed an extract from apple skins had a 57 percent lower risk of liver cancer.


7. Diabetes Management
The pectin in apples supplies galacturonic acid to the body which lowers the body's need for insulin and may help in the management of diabetes.


8. Weight Loss
A Brazilian study found that women who ate three apples or pears per day lost more weight while dieting than women who did not eat fruit while dieting

9. Asthma Help
One recent study shows that children with asthma who drank apple juice on a daily basis suffered from less wheezing than children who drank apple juice only once per month. Another study showed that children born to women who eat a lot of apples during pregnancy have lower rates of asthma than children whose mothers ate few apples.

10. Bone Protection
French researchers found that a flavanoid called phloridzin that is found only in apples may protect post-menopausal women from osteoporosis and may also increase bone density. Boron, another ingredient in apples, also strengthens bones.

Reference: http://sulistianto111.blogspot.com/2011/03/10-benefits-of-apple.html

Malignant Mesothelioma, Jenis Keganasan yang Makin Mendapat Perhatian

Malignant Mesothelioma, adalah salah satu kanker yang jarang terjadi. Meskipun demikian, akhir-akhir ini kekerapan terjadinya kian berkembang.

Mesothelioma berkembang pada lapisan pelindung yang melapisi banyak organ-organ dalam tubuh, yaitu mesotelium. Kanker pada mesotelium ini biasanya disebabkan oleh kekerapan paparan asbes.

Bagian yang paling sering terkena adalah pleura (lapisan yang membungkus paru), bagian lain yang bisa terkena ialah peritoneum (lapisan rongga perut), perikardium (lapisan yang menutupi jantung), dan tunika vaginalis (lapisan yang menutupi testis).

Kebanyakan orang-orang yang terkena malignant mesothelioma bekerja sebagai kuli bangunan atau pekerja yang sering terpapar dengan asbes. Namun, bisa juga terjadi pada orang-orang yang tinggal di pemukiman beratapkan asbes (seperti di rumah sangat sederhana-RSS).

Tidak seperti kanker paru, malignant mesothelioma tidak berhubungan dengan kebiasaan merokok penderita, artinya malignant mesothelioma tidak disebabkan oleh zat karsinogenik di dalam rokok.

Gejala-gejala dari malignant mesothelioma adalah sesak napas (karena efusi pleura), nyeri dada, dan yang khas untuk keganasan ialah penurunan berat badan yang ekstrim.

Diagnosis penyakit ini dapat diduga dengan Chest X-Ray dan CT Scan, serta dikonfirmasi dengan biopsi (pengambilan sampel jaringan) dengan bantuan torakoskopi, dan uji mikroskopik.

Akhir-akhir ini para ilmuan sedang mengembangkan teknik-teknik yang dapat dipakai untuk mendeteksi secara dini terjadinya malignant mesothelioma.

Penderita kanker malignant mesothelioma ini, meskipun telah ditatalaksana dengan kemoterapi, terapi radiasi, dan pemebedahan, tetap saja mempunyai prognosis yang buruk.

Translate:

Malignant Mesothelioma is one of the rare cancer. However, lately growing frequency of occurrence.


Mesothelioma develops in the protective layer that lines many organs in the body, namely mesotelium. Cancer in mesotelium frequency is usually caused by asbestos exposure.


The most often affected are the pleura (the lining that surrounds the lungs), other parts that could be affected is the peritoneum (abdominal cavity lining), the pericardium (the layer covering the heart), and tunica vaginalis (the layer covering the testicle).

Most people who are affected by malignant mesothelioma worked as construction laborers or workers who are often exposed to asbestos. However, it can also occur in people who live in settlements of asbestos roof (like a very simple home-RSS).

Unlike lung cancer, malignant mesothelioma is not related to smoking habits of patients, meaning that malignant mesothelioma is not caused by carcinogenic substances in cigarettes.

Symptoms of malignant mesothelioma are shortness of breath (due to pleural effusion), chest pain, and are typical for malignancy is an extreme weight loss.

Diagnosis of this disease can be predicted with Chest X-Ray and CT scan, and confirmed with a biopsy (tissue sample) with the help torakoskopi, and microscopic tests.

Lately, scientists are developing techniques that can be used to detect early occurrence of malignant mesothelioma.

Patients with malignant mesothelioma cancer is, although it has been treated with chemotherapy, radiation therapy, and pemebedahan, it still has a poor prognosis.

Video Operasi Penyakit Arteri Koroner

Faktor Risiko Terjadinya Penyakit Jantung Koroner

Berusia lebih dari 45 tahun (bagi pria)
Sangat penting bagi kaum pria mengetahui usia rentan terkena penyakit jantung koroner. Pria berusia lebih dari 45 tahun lebih banyak menderita serangan jantung ketimbang pria yang berusia jauh di bawah 45 tahun.

Berusia lebih dari 55 tahun atau mengalami menopause dini sebagai akibat operasi (bagi wanita)
Wanita yang telah berhenti mengalami menstruasi (menopause) secara fisiologis ataupun secara dini (pascaoperasi) lebih kerap terkena penyakit janting koroner apalagi ketika usia wanita itu telah menginjak usila (usia lanjut)

Riwayat penyakit jantung dalam keluarga
Riwayat penyakit jantung di dalam keluarga sering merupakan akibat dari profil kolesterol yang tidak normal, dalam artian terdapat kebiasaan yang "buruk" dalam segi diet keluarga.

Diabetes
Kebanyakan penderita diabetes meninggal bukanlah karena meningkatnya level gula darah, namun karena kondisi komplikasi ke jantung mereka. (Wikipedia)

Merokok
Merokok telah disebut-sebut sebagai salah satu faktor risiko utama penyakit jantung koroner. Kandungan nikotin di dalam rokok dapat merusak dinding (endotel) pembuluh darah sehingga mendukung terbentuknya timbunan lemak yang akhirnya terjadi sumbatan pembuluh darah.

Tekanan darah tinggi (hipertensi)
Tekanan darah yang tinggi dan menetap akan menimbulkan trauma langsung terhadap dinding pembuluh darah arteri koronaria, sehingga memudahkan terjadinya arterosklerosis koroner (faktor koroner) yang merupakan penyebab penyakit jantung koroner. (USU)

Kegemukan (obesitas)
Obesitas (kegemukan yang sangat) bisa merupakan manifestasi dari banyaknya lemak yang terkandung di dalam tubuh. Seseorang yang obesitas lebih menyimpan kecenderungan terbentuknya plak yang merupakan cikal bakal terjadinya penyakit jantung koroner.

Gaya hidup buruk
Gaya hidup yang buruk terutama dalam hal jarangnya olahraga ringan yang rutin serta pola makan yang tidak dijaga akan mempercepat seseorang terkena pneyakit jantung koroner.

Stress
Banyak penelitian yang sudah menunjukkan bahwa bila menghadapi situasi yang tegang, dapat terjadi aritmia jantung yang membahayakan jiwa.

Penyakit Arteri Koroner, Bagaikan Jalan Raya yang Macet

Teman-teman, lihat gambar ini.

Dari gambar, dapat kita lihat sebuah replika aliran darah pada jantung. Darah, secara normal mengalir melalui pembuluh darah sambil mengangkut oksigen untuk disebarkan ke jaringan dan organ pada tubuh. Oleh karena itu, aliran darah yang lancar memungkinkan pasokan oksigen ke seluruh tubuh terjamin. Sebaliknya, aliran darah yang tidak lancar menyebabkan berbagai jaringan atau organ pada tubuh kekurangan oksigen padahal oksigen merupakan makanan/sumber kehidupan utama bagi sel-sel yang ada dalam jaringan-jaringan tubuh. Akibatnya, jaringan akan kelaparan bahkan mati bila terus-terusan lapar. 

Perhatikan gambar lagi, pada gambar sebelah kanan (Gambar B) terlihat aliran darah dihalangi oleh sesuatu yang digambarkan berwarna kuning. Sesuatu itu disebut plak. Plak adalah tumpukan hasil metabolik (terutama lemak) yang rentan/riskan menumpuk di pembuluh darah sehingga menyebabkan pembuluh darah tertutup (mampet) ketika dilalui oleh darah.

Hal ini dapat dianalogikan serupa dengan jalan raya, yang ketika terlalu banyak kendaraan, maka berakibat terjadinya kemacetan. Bayangkan, bila kendaraan-kendaraan dengan kepentingan khusus (seperti ambulans, pengantar barang, dll) sedang berada di jajaran belakang saat kemacetan, maka akan berakibat cukup fatal.

Sama halnya dengan pembuluh darah pada jantung, apabila terjadi kemacetan aliran darah, maka berakibat fatal terhadap jaringan-organ yang notabene harus mendapatkan suplai oksigen dari darah.

Sebagai contoh, pada gambar di atas, kita juga dapat melihat aliran darah yang terhambat oleh plak (sudah disebutkan di atas). Aliran darah tersebut seharusnya menyampaikan oksigen darah ke otot-otot pada jantung, tetapi karena plak menghalangi darah lewat ke otot-otot jantung, maka otot-otot jantung kekurangan suplai oksigen. Hal ini mengakibatkan sel-sel otot jantung mengalami nekrosis (kematian) sehingga kehilangan funsginya. Penyakit dengan mekanisme demikian disebut penyakit arteri koroner.

Penyakit tersebut menimbulkan gejala-gejala seperti nyeri dada, sesak napas, berdebar-debar, denyut jantung terasa lebih cepat, mual, pusing, dan lemah. Penyakit ini sering terjadi pada orang-orang kalangan yang hobi merokok dan mengkonsumsi makanan berlemak.

Tujuh Cara Menjaga Kesehatan Jantung

Di saat berbagai jenis penyakit jantung "membunuh" banyak orang di negara maju dan berkembang, ternyata ada banyak cara yang dapat kita terapkan untuk menjaga atau mencegah penyakit jantung itu menjangkiti kita.

Para ilmuan, akhir-akhir ini telah menemukan berbagai faktor risiko yang mempengaruhi terjadinya penyakit jantung. Satu hal penting yang harus kita pelajari adalah bahwa masing-masing dari kita (perilaku kita) memiliki keterkaitan yang signifikan atas sebagian besar dari faktor-faktor risiko tersebut. Oleh karena itu, dengan mengendalikan perilaku kita yang menjurus pada kerusakan jantung, kita dapat mencegah bahkan mengurangi angka kejadian penyakit jantung yang mematikan ini. Bahkan seseorang yang mempunyai kecnderungan secara genetik pun dapat memanfaatkan perubahan perilaku (pola hidup sehat) untuk mencegah terjadinya penyakit jantung yang tidak diharapkan olehnya.

1. Me-manage pola makan (diet) dan berat badan. Satu bentuk pola makan yang buruk seperti makan di malam hari, makan terlalu banyak, makan tanpa sayuran, dll, dapat mengakibatkan terjadinya obesitas (kegemukan). Obesitas dapat merusak sistem vaskuler (pembuluh darah), sehingga secara tidak langsung menyebabkan kerusakan pada jantung kita.
2. Membiasakan olah raga ringan yang berfrekuensi teratur. Kehidupan yang monoton tanpa gerak menyebabkan metabolisme tidak dilatih untuk berproses. Jarangnya seseorang bergerak menyebabkan penumpukan kolesterol dan kadar gula darah akibat gangguan (tidak lancarnya) metabolisme yang berlangsung. Latihan yang ringan (berat tidak disarankan) dapat membantu kelancaran proses metabolisme, apalagi bila latihan tersebut frekuensinya teratur dan konstan, tidak mendadak dan kebetulan. Kita dengan mudah dapat berjalan santai di pagi hari, atau jogging ringan bersama rekan kita, itu sudah cukup.
3. Tidak merokok. Dari semua hal yang membahayakan jantung, merokok adalah yang paling membahayakan. Nikotin, salah satu zat yang adiksi yang membahayakan jantung, terkandung di dalam rokok. Merokok tidak hanya menyebabkan penyakit jantung koroner, tetapi juga penyakit-penyakit lain seperti kanker paru, serta penuaan dini.
4. Me-manage tingkat kolesterol. Lemak darah seperti kolesterol dan trigliserid ialah determinan yang penting terkait penyakit jantung. Terlalu banyaknya kolesterol dan trigliserifd yang terkandung dalam tubuh, dapat menyebabkan sempitnya pembuluh darah, yang berakibat pada kerusakan sistemik, termasuk jantung. Cara mengatur tingkat kolesterol kita ialah dengan mengatur pola makan yang baik, misalnya: makan-makanan berlemak dalam jumlah yang memadai saja, jangan terlalu banyak: tiga kali sehari sudah terlalu banyak. 
5. Me-manage tekanan darah. Khususnya buat seseorang yang telah mengalami hipertensi (tekanan darah tinggi), mengontrol tekanan darah ialah cara yang efektif untuk mencegah terjadinya stroke dan serangan jantung. Mengurangi makan-makanan berlemak adalah salah satu cara yang efektif.
6. Me-manage stres. Para ilmuan juga telah mengutarakan bahwa stres menyebabkan irama jantung tidak normal. Apabila stres berlangsung secara kronis (berkepanjangan), maka akan menyebabkan makin besarnya risiko terkena penyakit jantung, bahkan dapat juga menyebabkan makin parahnya penyakit jantung yang telah dialami.
7. Me-manage kadar gula darah. Resistensi insulin akibat obesitas (karena terlalu banyak makan), dapat terwujud sebagai sindroma atau kumpulan gejala diabetik. Hal ini menyebabkan tingginya kadar gula darah dan meningkatnya masalah-masalah metabolik yang meningkatkan risiko terjadinya berbagai penyakit jantung.

Manfaat Air Putih

 

1. Menghilangkan rasa haus, dehidrasi, dan kering pada mukosa mulut.
2. Menciptakan mood sehari-hari lebih baik (memperbaiki mood yang terganggu)
3. Mengurangi rasa cemas/was-was, gelisah, dan marah.
4. Meningkatkan energi, konsenterasi, dan performa kerja.
5. Mencegah berbagai penyakit (berbagai penyakit pencernaan, serta sejumlah penyakit ginjal, hati, dan jantung) 
6. Mengurangi zat toksik (racun) dalam tubuh.
7. Menambah kebugaran tubuh.
8. Mempunyai efek kosmetika seperti pemeliharaan kulit serta manfaat kecantikan lainnya.

Oleh karena itu, minumlah air putih minimal 2 L per hari (8 gelas standar) ketika dalam aktivitas yang minimum. Apabila aktivitas yang dilakukan lebih berat, minumlah lebih banyak lagi. 

Sindroma Penglihatan Akibat Komputer

Jika anda menghabiskan banyak waktu di depan komputer, maka anda berpeluang terkena sindroma penglihatan akibat komputer (computer vision syndrome/CVS). CVS adalah istilah yang digunakan untuk menggambarkan kumpulan gejala yang disebabkan oleh penggunaan komputer yang berkepanjangan.

Terjadinya CVS ini ialah karena kesulitan mata beradaptasi terhadap piksel-piksel yang rumit di layar komputer.

Gejala seseorang yang mengalami CVS adalah:

• Mata kering
• Mata iritasi/merah
• Sakit kepala ringan
• Visus (penglihatan) berkurang
• Sensitifitas cahaya
• Pseudomiopia (ketidakmampuan sementara untuk fokus pada suatu objek yang jauh)
• Penglihatan ganda
• Nyeri bahu dan leher

Belakangan ini telah dikembangkan dan disebarluaskan "kacamata komputer" yang secara khusus didisain untuk kenyamanan pengguna komputer, terutama pengguna yang berkepanjangan (saya tidak tahu apakah kacamata ini dipakai di Indonesia).

Selain menggunakan kacamata khusus komputer, ada cara lain agar dapat mencegah CVS, yaitu:

• Sering berkedip ketika menggunakan komputer
• Atur pencahayaan komputer (biasanya dengan menekan Fn + arah kiri)
• Jangan biasakan menggunakan font kecil dalam komputer
• Sekali-kali berdiri dan berjalan sebelum mulai berhadapan dengan komputer lagi

NOISE as a HEALTH HAZARD

NOISE as a HEALTH HAZARD

Aage R. MǾller

Noise can be hazardous to health chiefly in two ways: (1) it can demage the ear, and (2) it can influance a number of other bodily functions. In addition, the permanent and temporary decrease in hearing acuity from noise exposure may make speech communication difficult. Noise can also maks warning signals. Thus, it poses a risk to safety and therefore a risk to the general health of workers.

Because the potential to cause damage to the ear is the most apperent and best-known health risk of noise, it will be discussed first. The other effect of noise will be discussed leter in the chapter.

EFFECT OF NOISE ON HEARING

Noise is commonly use to describe sound that are unwanted or unpleasant, in contrast to sound such as music or speech. Several text book, in fact, define noise as sound that is discordant and nonperiodic, probably because such sound often have such unpleasant qualities. The potential of noise to damage hearing, however, is entirely related to such physical properties as its intensity, the length of time over which subject are exposed to it, and its time pattern and is not related to wheather the sound is pleasant or not. It would therefore be more appropiate to use the general term sound in discussing the hazards to hearing. However, we will use noise to describe sound that may be damaging to the ear because this word has traditionally had negative connotations and thus will be identified more readly with health hazards.

Noise of intensity and duration sufficient to cause hearing impairment are usually assosiated with industry. However, since it is solely the physical characteristics of the sound that determine its potential for causing hearing loss, the origin of the sound by itself has no influence on the degree of risk its presents for hearing damage. Thus sound to which people are exposed during recreational activities may pose as great a hazard to hearing as noise assosiated with work activities (including military activities, where gunshot noise in particular poses a high degree of risk).

Individual variation insusceptibility to noise is great, and probably factors that are not yet known affect individual’s risk of noise-induced hearing loss. Thus, only the degree of risk (probability) for acquiring a hearing loss can be predicted on the basis of our present knowledge about how the physical characteristic of noise and time of exposure to noise affect hearing. The risk of noise induced-hearing loss is in proportion to the intensity and duration of the noise, with the risk of injuring one’s hearing increasing with the length of exposure. The character of the noise-continuous or transient (such a gunshot)- also plays a role. Thus different type of noise pose different degrees of risk of hearing loss, even though the overall intensity of the noises is the same impulsive sounds such as gunshots generally pose a great risk than continuous noise.¹ The spectral composition of the noise and the pattern of exposure (constant intensity vs fluctuating intensity or noise interpersed with intervals of relative silance) are also important factors that affect the degree of risk of hearing loss.

The firs effect of expossing an ear to noise of a certain intensity for a certain period of time is a reduction in hearing (elevated auditory threshold). This reduction in hearing is greatest immediately after the exposure and decrease gradually. If the noise has not been too loud or the exposure too long, hearing will gradually return to its original level, a type of hearing loss known as a temporary threshold shift (TTS). If the noise is louder than a certain value or the exposure time is longer than a certain time, causing a permanent threshold shift (PTS). The time course of the change in hearing threshold is illustrated schematically in Figure 28-1.

While the TTS probably result from temporarily impaired function of the sensory cells in the inner ear, a PTS is associated with irreversible damage to these cell. This damage can be seen when the cells are examined histologically under high-power magnification.an example of such damage is illustrated in Figure 28-2, which shows a scanning electron micrograph of the sensory cells (hair cells) in the inner ear of a monkey before and after exposure to gunshot noise. Hearing in person with damage hair cells cannot be restored. Noise exposure may also damage neural structures in the auditory nervous sistem, but the exact nature and extent of this damage is poorly understood.

As has been noted, the intensity and duration of exposure to noise primarily determine the degree of permanent hearing damage caused by the noise, and the hazard to hearing increases as the intensity and length of exposure increase. The distribution of noise’s energy over the requency spectrum is also important: low-frequency sounds are considered to be less damaging than high-frequency sounds of the same physical intensity. Another parameter of noise important in determining its potential to cause hearing loss is whether it is continuous or impulsive in nature; impulsive noise is more likely to cause hearing loss than is continuous noise of the same intensity and spectrum.

Figure 28-1. schematic diagram ilustrating how noise can affect hearing. The graph shows the hearing loss (threshold sift) at 4000 Hz a certain time (horizontal axis) after noise exposure. Noise with an intensity below a certain value is expected to give rise to a temporary threshold sift (90 dB, 7 days curve), while a louder noise (100 dB, 7 days) result in a permanent threshold sift. A very intense noise (120 dB, 7 days) give rise to a considerable permanent sift in threshold. (Adapted from Miller J: J Acoust Soc Am 56:3, 1974, with permission.)

Because there is a great individual variation in susceptibility to noise-induced hearing loss, people who are exposed to exactly the same noise for exactly the same period of time may not suffer the same degree of hearing loss. Some people can tolerate high intensity noise for a lifetime and not suffer any substantial degree of hearing loss, but other people may acquire a substantial hearing loss from exposure to much less intense noise. Attemps have been made to estimate an individual’s susceptibility to PTS by the degree of TTS evidenced on exposure to a test sound that is not loud enough to cause permanent hearing loss. However, the result of these attempts have been rather discouraging, and it seems there is no correlation between susceptibility to PTS and the degree of TTS in any individual person. At the present time the only way to determine such individual susceptibility is to test at frequent intervals the hearing of workers exposed to loud noise.

Figure 28-2. Scanning electron micrographs of sensory cells (hair cells) from a small segment of the basilar membrane of a monkey. A. Normal hair cells. B. Hair cell after noise exposure (gunshot). (Courtesy Proffesor Hans Engstrom, Uppsala, Sweden.)

Figure 28-3. Threshold sift (hearing loss) at 4 kHz as a function of the total amount of noise exposure (emission value). Each point representa an individual person, and the solid lines are the mean values of the threshold sift. The emission value is L_eq + 10 log (T), where L_eq represents the sound level (measured wit A-weighting) that is exceeded during 2% of the exposure time T (in months). For example, exposure to 85-dB noise during 20 years of work corresponds to 85 + 10 log (20 × 12) = 85 + 10 log 240 = 85 + 24 = 109. the threshold sift given is the threshold sift measured minus the threshold sift assumed to be normal considering the age of the person (everyone experiances some hearing loss as part of the normal process of aging, which is called presbycusis). For continuous noise, L_eq deviates only slightly from the A-weighted sound intensity, but for noise that contains transient or intemittent noise (i.e., noise that vary consideraply in intensity), the difference between these two values is great. The graph thus shows that the average hearing loss as a result of exposure to continuous noise with a sound intensity of 85 dbB (A) or 20 years is less than 5 dB at 4 kHz, but that a number of people experiance a 30-dB to 40-dB threshold sift. (From Burn W and Fobinson DW: Hearing and Noise in Industry. London, HMSO, 1970.)

However, the distribution of susceptibility to PTS in a large population is relatively well known. Figure 28-3 shows hearing losses at 4 kHz for a number of people as a function of the noise emission level.² This measure combines the two characteristic of noise (duration and intensity) assumed to be of the greatest importance in defining its potential for harm but does not take into account the nature of the noise (time pattern or spectrum).

Although we do not know whoch factor determine susceptibility to noise, recent studies in animals have pointed to ward some factors that may predispose a subject to noise-induced hearing loss. For example, study in rats that werw genitically predisposed to high blood presure showed that these rats acquired a higher degree of hearing loss from noise exposure than did normal rats when boths groups werw exposed to noise for their entire lifetime.^3,4 Although these findings have not been duplecated in humans, the result of some human studies support a relationship between high blood presure and hearing loss from noise exposure⁵ (see also p. 529). Alteration in cochlear blood flow may also affect susceptibility to noise.⁶ More recent animal studies have disclosed that activation of particular neural circuit in the brainstem (the olivocochlear bundle) may protect the ear from the noise-induced hearing loss.⁷ the results of these studies undeline the complexity of the way noise affects and gives rise to hearing loss; they also shed some light on several unexplained effects of the exposure pattern and nature of the noise in producing noise-induced hearing loss. Research along these lines is likely to provide knowledge that may lead within the foreseeable future to development of more efficient ways to assess an individul’s susceptibility to noise hearing loss.

NATURE OF NOISE-INDUCED HEARING LOSS

Hearing loss is measured in decibles^* relative to normative average hearing threshold. Such baseline thresholds are obtained-

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^*dB, the abbreviation for decibel, is a logarithmic measure, used here as a measure of sound pressure. One decibel is one tenth of a logarithmic unit (a ratio of 1 : 10). The reason for using a logarithmic measure of sound pressure to measure hearing threshold is that the subjective sensation of sound intensity is approximately related to the logarithmic of the sound pressure.

Figure 28-4. Average estimated hearing losses for industrial workers exposed to noise of a certain level for different lengths of time. [From Taylor et al: J Acoust Soc Am 38:113-120, 1965]

by measuring the hearing thresholds of young people who have had known exposure to noise. However slightly different standards for “normal” hearing are used in different parts of the world (American National Standard Institute [ANSI] in the United States⁸; International Organization for Standardization [ISO] in Europe⁹), which may need to be taken into account when the risk of noise-induced hearing loss is evaluated. The difference between the hearing threshold of an individual and the “standard” hearing threshold is known as the hearing level (HL) and is measured in decibels. When the HL is plotted in the vertical axis as a function of the frequency tested, the resulting graph is known as an audiogram. Usually, the hearing thresholds are determined only in the frequency range of 125 to 8000 Hz (8 kHz), despite the fact that a person with normal hearing can hear sounds in the frequency range of 18 to 20,000 Hz.

Examples of estimated hearing loss taken from data obtained in a study of workers in the weaving industry are shown in Figure 28-4 as “predicted” audiograms. The individual curves on this audiogram represent different durations of noise exposure in years. As seen, the estimated hearing loss is greatest in a restricted frequency range around 4 kHz, but with continuing exposure the frequency range of hearing loss widens and the magnitude of the loss increases. These results obtained in weavers are typical for those exposed to noise in various manufacturing industries where the noise tends to be a broad spectrum and continuous in nature. Although many hypotheses have been presented, we do not know why the greatest hearing loss resulting from exposure to the broadband noise that is common in industries occurs around 4 kHz. We do know, however, that the frequency distribution of hearing loss depends to some extent on the spectrum of the noise. When the hearing-damaging effect of a noise with a narrow spectrum (i.e., its energy is limited to a narrow range of frequencies) is studied, the hearing loss usually is greatest over a frequency range slightly above (about ½ octave) the range at which the notice has its highest energy. However, the precise relationship between the spectrum of a noise and the distribution of hearing loss it can cause is not fully known.

Since hearing loss induced by industrial noise usually first affects the hearing threshold at frequencies around 4000 Hz (and thus above the 300- to 3000-Hz range essential for perception of speech), a person who suffers from noise-induced hearing loss often does not notice the loss until it has reached a relatively severe level. However, hearing tests can easily reveal hearing loss may indicate that the person in question is particularly susceptible to noise-induced hearing loss, frequent testing of the hearing of workers exposed to noise is important. In fact, it is powerful way to identify people who are particularly susceptible to noise exposure before they acquire a hearing handicap.

Being unable to hear weak sounds is not the only way that the hearing of people with noise-induced hearing loss is impaired. The deterioration of sensory cells in the inner ear that is caused by noise exposure also leads to a change in the way which sounds are perceived. Thus, although a person with a noise-induced hearing loss may understand some sound through amplification (asking people to speak louder or using a hearing aid); the quality of the sound is impaired. Such a person may have difficulty understanding speech, even when the sound has been amplified properly. This aspect of noise-induced hearing loss makes hearing more difficult when the individual is in a noisy environment or in a place in which several people are speaking at the same time. Many people with noise-induced hearing loss are also severely troubled by ringing in the ears (tinnitus).

NOISE STANDARDS

To reduce the risk of noise-induced hearing loss, a number if recommendations of acceptable noise levels have been established and appear in the form of noise standards. Different countries have adopted slightly different standards, and the ways in which standards are enforced also differ. All presently accepted standards use a single-value measure of the noise level and the duration f the exposure to calculate the risk the noise represents for causing permanent noise-induced hearing loss. Some of these standards include correction factors regarding the nature of the sound, for instance, impulsive vs continuous sounds.

Establishing Noise Standards and Damage Risk Criteria

The maximal noise level and duration accepted in most industrial countries is either 85 or 90 dB(A),* for 8 hours a day, 5 days a week. In Europe the 85-dB(A) level is more common, whereas in the United States 90 dB(A) is the level stated by the Occupational Safety and Health Administration (OSHA), although certain measures have to be taken if workers are exposed to noise levels above 85 dB(A) (for a review of noise standards see Suter¹⁰)

Individual variation in susceptibility to noise-induced hearing loss makes it impossible to predict what hearing loss an individual will acquire when he or she is exposed to a certain noise. Therefore, at best standards merely predict the percentage of people in a population with normal hearing who will acquire less than a certain specified (acceptable hearing loss when exposed to noise no louder than a certain value. When evaluating the so-called noise standards it is important to keep this in mind¹¹. Noise standards are thus based on the fact that a certain percentage of normal-hearing population will acquire a permanent hearing loss (threshold elevation) greater than a certain value averaged over certain frequencies. The “allowed” hearing loss and the frequencies at which it is measured vary among standards and have been modified at intervals.

_____________________________________________________________________*The (A) after dB indicates that the noise spectrum has been weighted to place less emphasis on low frequencies that on high frequencies because low-frequency sounds generally post loss risk for causing hearing loss than high-frequency sounds.

There has been a tendency to adjust these criteria downwards to allow for less permanent hearing loss. In the beginning of the era in which efforts were made to reduce (or prevent) notice-induced hearing loss, the acceptable hearing loss was defined as the level of hearing loss at which an individual begins to experience difficulty in understanding everyday speech in quiet environment. This definition was based on the American Academy of Ophthalmology and Otolaryngology (AAOO) guidelines for evaluation of hearing impairment, ¹³ which state the ability to understand normal everyday speech at a distance of about 1,5 m (5 ft) does not noticeably deteriorate as long as the hearing loss does not exceed an average value of 25 dB at frequencies 500, 1000, and 2000 Hz. On the basis of this, an average hearing loss of 25 dB at frequencies 500, 1000, and 2000 Hz was taken to be hearing loss that resulted in a just-noticeable handicap. This level of hearing loss was originally designated in United States at the level of handicap at which a worker was entitle to receive workman’s compensation for loss of earning power (it is puzzling that this degree of hearing loss was later designated as acceptable)

More recently, some controversy about what constitutes a hearing impairment has emerged. The AAOO had focused n average hearing loss at 500, 1000, and 2000 Hz,¹⁴ but the National Institute for Occupational Safety and Health (NIOSH) criteria document¹⁵ states that the ability to hear sounds at 25 dB below normal at 500, 1000, and 2000 Hz not sufficient to assure that speech will be understood might be adequate under the optimal conditions in which speech reception is usually tested for audiological purposes. It has therefore been advocated that the average hearing loss at 1000, 2000, and 3000 Hz be used as a basis for evaluating the effects of noise exposure, instead of at 500, 1000, and 2000 Hz. However, to date this definition has not won general acceptance.

The Environmental Protection Agency (EPA) recommended to OSHA that 25 dB average hearing loss at 1000, 2000, and 4000 Hz be accepted the standards for when difficulties in understanding normal speech begin.¹⁶ The justification for excluding the hearing level at 500 Hz from calculations of hearing handicaps due to noise exposure is that hearing loss at 500 Hz is more often the result of factors other than noise exposure, such as middle ear disease. The inclusion of the hearing level at 3000 Hz in a composite describing the ability to understand normal speech seems justified because hearing at 3000 Hz is important for speech perception.

It has also been suggested that the average hearing level of 25 dB be replaced by 22 dB, while keeping the same frequencies defined by the EPA (1000, 2000, and 4000 Hz).¹⁷ The reasoning behind this suggestion was endorsed by AAOO, which, however, maintained that a “low fence” of 25 dB was acceptable.¹⁸ In general, these changes in hw measured pure tone thresholds should be weighted to obtain a single number to best define a hearing handicap that affect speech communication have led to a more realistic way describing the handicap of hearing loss.

Only hearing loss induced by noise has been discussed as imposing a handicap. However, the total acceptable hearing loss is that induced by noise plus whatever is assumed to be result of other causes such as age (presbycusis). Presbycusis also varies greatly among individuals. Nevertheless, it is the total hearing loss that determines the degree of handicap. So although noise induced hearing loss may not be at a level regarded to be a handicap according to the noise standard, older persons may suffer a level of hearing loss that can be handicapping, despite not having been exposed to noise that exceeded the standard.

Present Noise Standards. In the United States, legislation that covers noise includes Federal Aviation Act of 1958, the 1969 Amandement of Walsh-Healy Public Contracts Act, the Occupational Safety and Health Act of 1970, the Noise Control Act 0f 1972, and the Mine Safety and Health Act 0of 1978. These acts require certain agencies to regulate noise.

In Europe, legislation in various countries on industrial noise limitation has largely been guided by recommendations made by the ISC. These recommendations have generally set an upper limit of acceptable noise exposure at 85 dB(A) for 8 hours a day, 5 days per week, but in the United States 90 dB(A) has been standard.

The ISO recommendation is based on the probabilities of acquiring a hearing loss of 25 dB, averaged for 500, 1000 and 2000 Hz, with exposure to noises of different intensities for variable lengths of time. According to ISO recommendations,⁹ as much as 10% of a population with initially normal hearing will acquire a hearing loss of 25 dB or more, averaged over frequencies 500, 1000, and 2000 Hz, after 40 years of exposure to noise at a level 0f 85 dB(A). For 90 dB(A) noise level, those experiencing hearing loss increases to 21%. These values are based on studies of workers in weaving industry, and research indicates that the number of people with noise-induced hearing losses may be higher in other industries. However, the risk of hearing impairment doubles when the daily average noise exposure of 85 dB(A) increases to 90 dB(A), regardless of which data are used (see Suter¹⁰). Many European countries have chosen 85 dB(A) as the upper limit of acceptable noise exposure for 8 hours.

Recently, proposals have been put forward to lower the standard in the United States from 90 dB(A) to 85 dB(A).¹⁹ Accordingly, a recent OSHA hearing conservation amendment states that a noise monitoring program is mandatory in environments where the daily average of noise level is 85 dB(A) or higher.²⁰ The monitoring program must be so designed that it identifies people who are exposed to noise levels of 85 dB(A) (8-hours weighted average) or more. If people are exposed to noise levels s of 90 dB(A) or higher for 8 hours per day, measures must be taken to reduce the noise; and if the measures do not result in a reduction of noise level to at least 90 dB(A) or lower, workers must participate in a hearing conservation program and employers must make available to workers personal hearing protection devices (ear protectors) and conduct hearing tests at specified intervals during employment. If a hearing loss of 10 dB average over frequencies 2000, 3000, and 4000 Hz is detected, the person must be referred for further evaluation, and action must be taken to avoid further deterioration of hearing.

As early as 1972, NIOSH, in its criteria document,¹⁵ recommended that the 90 dB(A) permissible exposure limit be lowered to 85 dB(A). This recommendation also included suggestion about audiometrical testing, use of hearing protectors, notification of worker and how records should be kept. Only some of these suggestion were accepted by the U.S. Secretary of Labor, however, and the permissible exposure limit still remains at 90 dB(A), although audiometrical testing and certain other hearing conservation measures are now required when workers are exposed to noise above 85 dB(A). It has been advocated that noise standards be modified to reduce the number of people who acquiring hearing loss that can be regarded as a social handicap. The maximal tolerable noise level for 8-hour exposure is around 75 dB(A) if significant noise-induced hearing loss is to be eliminated.²¹ One of the main obstacles in adopting lower noise level such as the proposed 85 dB(A) was economic concerns: the cost of having all workplaces comply with such regulations was considered prohibitive. However, a much less expensive alternative, having all new equipment comply with regulations, was not even considered.

In the United States the EPA has regulated exposure to noise for the general population, deciding that no more than 5 dB hearing loss can be allowed at 4000 Hz as a result of environmental noise.²²

The fact that present noise standards are based on a simplified measure ofnoise, dB(A), adds to the uncertainty in predicting the risk ofacquiring a hearing loss through exsposure to a certain noise. As discussed earlier, this single-valued dB(A) measure does not contain any information about the spectrum of the noise, nor does it include any information about whether the noise contains sharp transient sounds or sounds with other characteristics important in hearing loss (see pic. 523).

Relationship Between Noise Level and Exsposure Time. A conversion factor must be established to estimate the acceptablenoise level when the exsposure to noise is less than 8 hours per day.again the conversion factors differs throughout the world. Thus, in Europe a 3-dB doubling factor is commonly used to estimate how high a noise level is acceptable when the exsposure time to the noise less than 8 hours per day, but a 5-dB doubling factor is used in the United Astates. A 3-dBdoubling factor implies that a reduction of the exsposure time by a factor of 2 is equivalent to a reduction in the noise level by 3 dB. That is, when the exsposure time is reduced from 8 hours per day to 4 hours per day, this rule assumes that a sound level 3 dB higher would be acceptable. Or if the exsposure time to noise is 2 hours per day, a sound level 6 dB higher can beaccepted and so on. This rule reflects the equal energy principle, which assumes that the total energy of the noise determines the risk for permanent hearing loss. However, using a 5-dB doubling factor means that every time the exsposure time is reduced by a factor of 2, he noise level can be increased by 5 dBwithout increasing the risk of hearing loss. This implies that exsposure to a noise for less than 8 hours per day decreases the risk more than the equalenergy principle implies and, therefore, that a higher total energy can be tolerated when the exsposure time to noise is reduced.

The noise standard presently in effect in the United States (29 CFR 1910.95) states that the maximum time-weighted exsposure level acceptable is 90 dB(A) for 8 hours with a 5-dB trading relation (doubling factor) between exsposure time and intensity: this trading relation means that although the maximum acceptable noise level for 8 hours is 90 dB(A), the maximum for half the time (4 hours) is 5 dB more (95 dB(A)). This noise level for this time is considered to be as hazardous as a 2-hour exsposure to 100 dB(A), a 1-hour exsposure to 105 dB(A), a 30-minute exsposure to 110 dB(A), and a 15-minute exsposure to 115 dB(A).

Using a fixed doubling factorimplies that a worker should be equally safe from acquiring a hearing loss when exsposed to noises of the same total sound energy, independent of whether the noises are presented as short-duration high-level noises or long-duration low-level noises. The value of the doubling factor for which this is true is, however, in dispite. The results of recent research indicate that a doubling factor of5 dB may be adequate for relatively low noise levels but that a smaller doubling factor (3 dB, i.e., equal energy) more correctly reflects the hazards presented by noise of a high level.

The validity of the equal energy principle has been questioned because animal exsperiment have shown hat hearing loss progresses more rapidly than predicted in respon to loud, short-duration sounds. Thus, it seems that a doubling factor ofless than 3 dB should be applied when the noise level is above a certain value. In the United States, standards have been thightened accordingly by stating that no worker should be exsposed to continuous noise above 115 dB(A) or impulsive noise above 140 dB(A),thus setting a ceiling for acceptable combination of noise intensity and exsposure time.

Because the level ofnoise exsposure usually varies during a work day, noise exsposure is often described by its equivalent level (Leq), whih is defined as the level of a noise that has the same average energy as the noise measured during a work day. The equivalent level is measured by summing the total noise energy to which a person is exsposed and dividig it by the duration of exsposure. The calculation of this equivalent level assumes that the equal energy principle discussed above is valid.

MEASUREMENT OF NOISE

Measurements ofsound levels are usually made at a location where people work. However, several factors are thereby left in doubt. One isthe efect of the head and pinna on the sound that actually reaches the ear. These two structures amplify sounds within a rather narrow range of frequencies (between 2 and 5 kHz) by as much as 10 to 15 dB. If the noise contains much energy in that range, the level of sound that actually reaches the ear may be as muchas 10 to 15 dB higher than the actual reading on a sound level meter placed in the person’s location when the person is not present.

Particular measurement problems also arise when the noise is impulsive in natur. Since the ear requires 100 ms to integrate a sound to perceive its loudness, noise level meters in earlier times integrated sound over about100 ms to provide a reading that was in accordance with the perceived loudness of the sound. This integration time is appopriate when the level of the sound is measured to assess itsability to annoy the hearer. However, whennoise levels are measured for the purpose of assessing the risk they pose to hearing, a much shorter integration time should be used because the cochlea integrates sound energy over 2 to 3 ms. Since presently available sound level meters (so-called impulse sound level meters) have an integration time of 35 ms, they underestimate the peak intensities of impulsive sounds and thus the potential ofsuch sounds to affect the cochlea (see Bruel23).

Another important factor of sound measurement is the variation in noise level atdifferent locations. Usually, a person does not maintain one work position but walks around,making the average exsposure difficult to estimate. Noise dosimeters have beendeveloped to improved the accuracy of measurements of noise exsposure. These devices, worn by the person whose noise exsposure is to be measured, register the sound level near the earor sometimes at other locations on the body and integrate the energy over an entire working day. Noise dosimeters thus function similiarly to radiation monitors.

PREVENTION OF NOISE INDUCED-HEARING LOSS

Naturally, the preferred method to preventing noise-induced hearing loss is to reduce the noise in a workplace below levels associated with significant risk to the people who work there. This method has often been disputes because of its serious economic implications; however, when noise restrictions are implemented onnew equipment only, the economic consequences are small. Although rebuilding old machinery for the purpose of reducing noise canbe costly, in the construction of new machinery state-of the-art engineering canreduce noise without excessive economic consequences. As an example, over a decade ago a new, fast papermaking machine with a noise level of 85 dB(A) was constructed using known technology to replace old machinery with a noise level of more than 110 dB(A). In fact, the noise level did not exeed 82 dB(A) in many workplaces in which this new equipment was installed, and the total cost ofreducing noise was only 1.1% of the total cost of the plant.

When old equipment is to be converted, it may cost less than $1000 per worker to comply with 90 dB(A) standards and about $1600 per worker to comply with 85 dB(A) standards (see Bruce,25 Table 4, page 609; see also Suter10). Undeniably, the cost of noise reduction inseveral industries is greater than in the example given,but it is equally obvious that in many branches of industry the costs is less, and there may evenbe cases in which the cost would be negligible. For this reason,setting a noise standard at a certain dB(A) value may in some cases be counterproductive because it provides no initiative to reduce the noise level below the standard, even when substansial reductions in noise level, beyond that necessary to meet the standard, could be achieved at minimal cost and improve worker comfort and productivity immeasurably.

It has been claimed that the problem of noise-induced hearing loss can be solved by personal protection devices (ear defenders). However, wearing ear protectors for long periods maybe hot and inconvenlent, and they impair speech communication evenbeyond the impairment caused by the noisy environment. In addition, ear protectors make it more difficult for people to hear alarm signalas or other acoustical signs of danger.

Nevertheless, there are times when ear protectors are appropriate. Two types are in common use: earmuffs, which are attached to a helmet or headband, and earplugs. Earmuffs can be removed more easily than earplugs and are therefore bettersuited for intermittent use, for example, when people are walking in and out ofnoisy area (such as airports), whereas earplugs are most practical for people who spend long periods of time in noisy environment. The sound attenuation of different types of earplugs and earmuffs depends not only onthe type ofdevice but also on how well it fits their individual person. Even results of laboratory testing where more deal situations can be achieved show great variability. When the sound attenuation of various protective devices is measured in the laboratory, earmuffs attenuate more than earplugs do. However, when hearing loss is assessed in people using these two types of ear protectors, earmuffs are usually shown to be less efficient than earplugs, eventhough earmuffs attenuate sound more. This discrepancy maybe due to the way sound atenuation is measured, or possibly since earmuffs are easier to remove, they may not always be worn when indicated. In addition, earmuffs tend to lose some of their sound attenuating power over time, thus they become lessefficient in reducng noise-induced hearing loss. Earplugs may also offer more efficient protection to some individuals but les to others because earplugs may must fit into the ear canal,the size of which varies widely in people. The sound attenuating power of earmuffs is less dependent on the anatomy of the wearer.

These problems were studied recently in shipyards, where there is often a combination ofintense, relatively continuous noise and superimposed in palsive noise, thus presenting an extreme hazard to hearing. Whenworkers were divided into two groups according to the intensity of the noise to which they were exsposed, those in the low-intensity noise group suffered more hearing loss than did those in the high-intensity noise group. This surprising result is likely related to the workers’ differing habits of wearing ear protectors: many more workers exsposed to high-intensity noise than low-intensity noise wore ear protectors. Infact,because the numbers of workers in the high-intensity noise group who did no wear ear protectors was so low, no analysis could be made inthis group of the relative benefit of wearing ear protectors, but in the low-intensity noise group, 1.73 times more workers who did not wear protectors suffered hearing loss than did those who wore protectors.

If the noise level to which people are exsposed cannot be reduced below harmful level, than measuring hearing loss at frequent intervals becomes are important part of a hearing conservation program, and it is the only known method of identifying people who are especially susceptible to noise-induced hearing loss. Since a hearing loss usualy beging in the high-frequency range, above the frequences used for everyday speech, it may not be noticed at first by the sufferer. However, suha hearing loss can easily be detected using ordinary pure tone audiometry. Persons who show such deterioration of hearing at high frequencies may be made aware that they are beginning to acquire a noise-induced hearing loss. The progress of hearing deterioration can usually be halted by moving to a les noisy environment, thus preventingthe hearing loss from reaching levels atwhic it becomes a social handicap. Modern hearing conservation programs focus on identifying persons who risk acquiring such a hearing loss so that they can take stepsto avoid a handicap. Many more people could not doubt be spared such a decline in the quality of their lives if more would take these simple precautions.

EFFECTS OF NOISE ON OTHER BODILY FUNCTIONS

The effects ofnoise on bodily functions other than hearing are poorly understood. Noise exsposure has been reported to cause an increase in blood pressure and alterations in other important bodily functions such as changes (ususally increases) inthe secretion of pituitaryhormones. However, more experimental evidence needstobe gathered to determine what the exact effects are and to distinguish between acute and long-term effects of noise on these functions.

Alterations in the body’s immune reactions and an increase in sensitivity to epinephrine and norepinephrine of the vascular system have been reported. Although it is known that the acute effect of noise on autonomic reactions increases as noise intensity is increased, theeffect of the time pattern of noise onthis response is less well understood than is its effect on hearing we know little about the ability of noise to alter excretion of pituitary hormones over extendedperiods of time.

It has been known for a long time that workers in noisy industries have a higher incidence of peripheral circulatory problems and heart problems than do those who are not exsposed to such high level of noise. However, because many other adverse factors besides noise exist in industrial environments, it has been difficult to identify the results of noise exsposure alone.

The efect of noise on blood pressure perhaps has been most thoroughly studied but has not been fully elucidated. During acute exsposure to noise, blood pressure ususally increases. The effect of noise on this bodily function is assumed o be mediated by the autonomic nervous system. Some reports have shown that prolonged exsposure to noise had a lasting effect on blood pressure in monkeys. Inother studies no effect was found on the normal increases inblood pressure with age that occurs inrats with normal blood pressure atbirth nor in animals with hereditary high blood pressure (spontaneoously hypertensive rats) when such rats were exsposed to noise for heir entire lives. (Unexpectedly, however, the spontaneously hypertensive rats developed considerably greater degrees of hearing loss from exsposure to noise than did rats without this hereditary predisposition to high blood pressure.)

Some retrospective studies (e.g., Jonsson and Hansson) of the effects ofexsposure to noise on the blood pressure of industrial workers found that workers who were exsposed to industrial noise had higher systolic and diastolic blood pressure, but other studies (e.g., Sanden and Axelsson) found no relationship between noise-induced hearing loss and blood pressure inshipyard workers. However, shipyards workers who had the highest degress of noise-inducedhearing loss had the greatest increases in heart rate during work, although the increases were not correlated with noise level. Again, there is no evidence that such an increases in heart rate has any long-term effects. If the results of the above-mentioned experiments in spontaneously hypertensive rats can be applied to human, then the results of he study of hypertension reported by Jonsson and Hansson may have to bereevaluated: by using hearing loss as the criterion for degree of noise exsposure they may have inadvertently selected workers who were predisposed to hearing loss because of their hypertension and not vice versa, as was intended.

SOUNDS ABOVE AND BELOW AUDIBLE FREQUENCY RANGE (ULTRASOUND AND INFRASOUND)

Sounds not audible to humans because their frequencies are outside our audible range are known as ultrasounds and infrasounds. The range of hearing in humans is usually given as 16 to 20,000 Hz in young people. The high-frequency limit usually shifts downward with age at 50 years it averages 10,000 Hz, although there is great individual variation. While the high-frequency limit is well defined (the hearing threshold rises abruptly when that frequency is exceeded), threshold increases much more gradually at the lower end of frequency scale, and sounds with frequencies below 10 Hz may be audible if they are intense. There is no evidence to indicate that exposure to sounds that are not audible can damage the ear.

Ultrasounds are heavily attenuated when transmitted in air and therefore decreases rapidly in intensity with distance from the source. Although very high intensities of ultrasound can kill furred animals such as mice, rats and guinea pigs because of the buildup of heat by sound absorption in the fur, such an effect could not occur in humans because bare skin cannot absorb enough energy to cause damage.

Exposure to low-frequency sound (infrasound) of high intensity has lately been reported to cause variation diffuse symptoms such as headache, nausea, and fatigue. Although few controlled studies have been conducted, it is possible that exposure to such sound may have some effect on general bodily functions. The result of some recent experiments indicates that infrasounds may decrease blood pressure, possibly through stimulation of the vestibular part of the inner ear. However, there is no evidence that such sounds can be hazardous to hearing.

REFERENCES

1. Price GR, Kim HN, Lim DJ, Dunn D: Hazard from weapons impulses: Histological and electrophysiological evidence. J Acoust Soc Am 85:1245-1254, 1989
2. Burns W, Robinson DW: Hearing and Noise in Industry. London, Her Majestv`s Stationery Office, 1970, p 241.
3. Borg E, Møller AR: Noise and blood pressure Effects of lifelong exposure in the rat. Acta Physiol Scand (Stockh) 103:340-342, 1978.
4. Borg E: Noise, hearing, and hypertension. Scand Audiol (Stockh) 10:125-126, 1981a
5. Jonsson A. Hansson L: Prolonged exposure to a stressful stimulus (noise) as a cause of raised blood pressure in man. Lancet 1:86-87, 1977.
6. Axelsson A, Borg E, Hornstrand C: Noise effects on the cochlear vasculature in normotensive and spontaneously hypertensive rats. Acta Otolaryngol (Stockh) 96:215-225, 1983.
7. Rajan R, Johnstone BM: Contralateral cochlear destruction mediates protection from monaural loud sound exposures through the crossed olivocochlear bundle. Hear Res 39:263-278, 1989
8. American National Standard Institute (ANSI) Standard for Audiometrics, S3.6, 1969.
9. International Organization for Standardization (ISO): Assessment of Occupational Noise Exposure for Hearing Conservation Purposes. (Recommendation R1999) 1971
10. Suter AH: The development of federal noise standards and damage risk criteria. In Lipscomb DM (ed) Hearing Conservation in Industry, Schools, and the Military. London: Taylor & Francis Publishing Co., 1988, pp 45-66
11. Kryter KD: Impairment to hearing rom exposure to noise. J Acoust Soc Am 53: 1211-1234, 1973.
12. Møller AR: Noise as a health hazard. Ambio 4:6-13, 1975.
13. American Academy of Ophthalmology and Otolaryngology (AAOO), Committee on Conservative of Hearing: Guide for Evaluation of Hearing Impairment, 1959
14. American Academy of Ophthalmology and Otolaryngology (AAOO): Guide for Conservation of Hearing in Noise (rev. ed.). Rochester, Minnesota: Trans Am Acad Ophthalmol Otolaryngol (suppl), 1973
15. National Institute for Occupational Safety and Health (NIOSH) Criteria for Recommended Standard: Occupational Exposure to Noise. Publication No. HSM 73-11001, 1972
16. Environmental Protection Agency (EPA): Testimony of Alvin F, Meyer, Jr. at the public hearings on proposed standards for occupational exposure to noise (submitted to U.S Department of Labor, Occupational Safety and Health Administration as Exhibit 57 in docket OSH-011), 1973
17. Suter AH: The Ability of mildly hearing impaired individuals to discriminate speech in noise. Washington, D.C.: U.S Environmental Protection Agency (EPA #550/9-78-100) and U.S. Air Force (#AMRL-TR-78-4) reports, 1978
18. American Academy of Ophthalmology and Otolaryngology (AAOO), Committee on Hearing and Equilibrium, and the American Council of Otolaryngology, Committee on Medical Aspects of Noise: Guide for evaluation of hearing handicap. JAMA 241: 2055-2059, 1979
19. Suter A: Essentials of noise regulations. Otolaryngol Clin North Am 21(3): 551-562, 1979
20. Occupational Safety and Health Administration (OSHA): Occupational Noise Exposure: Hearing Conservation Amendment, Final Rule. Federal Register 48:9738-9785, 1983
21. Kryter KD: Extra auditory effects on noise. In Henderson D, Hamernik RP, Dosaujh DS, Mills JHM (eds): Effect of Noise on Hearing. New York: Raven Press, 1976, pp 531-546.
22. Environmental Protection Agency (EPA), Office of Noise Abatement and Control Information on Levels of Environmental Noise: Requisite to Protect Public Health and Welfare with Adequate Margin of Safety. Washington, D.C.: Environmental Protection Agency (EPA#550/9-74-004), 1974
23. Bruel PV: Noise: Do We Measure It correctly? Naerum, Denmark: Bruel and Kjaer, 1975, p 40
24. Møller AR: Noise as a health hazard. Scand J Work Environ Health 3:73-79, 1977a
25. Bruce RD: The Economic impact of noise control. In Cantell RW (ed): Symposium on noise: Its effects and Control. The Otolaryngologic Clinics of North America Philadelphia: W.B. Saunders CO., 1979, pp 601-607
26. Erlandsson B, Hakanson H, Ivansson A, Nilsson P: The difference in protection efficiency between earplugs and earmuffs. Scand Audiol (Stockh) 9:215-221, 1980
27. Nilsson R, Lindgren F: The effect of long term use of hearing protectors in industrial noise. Scand Audiol (Stockh) (suppl) 12:204-211, 1980
28. Edwards RG, Hauser WP, Moiscev NA, Broderson AB, Green WW: Effectiveness of earplugs as worn in the workplace. Sound Vib 12:12-20, 1978
29. Nilsson R, Liden G, Sanden A: Noise exposure and hearing impairment in the shipbuilding industry. Scand Audiol (Stockh) 6: 59-68, 1977
30. Welch BL, Welch AS: Physiological Effects f Noise. New York Plenum Press, 1970
31. Osguthorpe JD, Mills JH: Non-auditory effects of low-frequency noise exposure in humans. Otolaryngol Head Neck Surg 90:367-370, 1982
32. Adrinkin AA: Influence of sound stimulation on the development of hypertension. Clinical and experimental results. Cor Vasa (Prague) 3:285-293, 1961
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34. Borg E: Physiological and pathogenic effect of sound. Acta Otolaryngol (Stockh) (suppl) 381:1-68, 1981 b
35. Borg E: Noise-induced hearing loss in normotensive and spontaneous hypertensive rats. Hear Res 8:117-130, 1982
36. Sanden A, Axelsson A: Comparison of cardiovascular responses in noise-resistant and noise-sensitive workers. Acta Otolayngol (Stockh) (suppl) 377:75-100, 1981

General Reference

Burns W, Robinson DW (eds): Hearing and Noise in Industry. London: Her Majesty’s Stationery Office, 1970

Hamernik RP, Henderson D, Salvi R (eds): New Perspectives on Noise-Induced Hearing Loss. New York: Raven Press, 1982

Kryter KD: The Effects of Noise ion Man, 2 edt. New York: Academic Press, 1985

Lipscomb DM (ed): Hearing Conservation In Industry, Schools, and the Military. Boston: Little, Brown & Company, 1988

Pickles JO: Physiology of the Ear, 2 edt. New York: Academic Press, 1988

Salvi RJ, Henderson D, Hamernik RP, Colletti V: Basic and Applied Aspects on Noise-Induced Hearing Loss. New York: Plenum Press, 1985