潜水知识

Q: 什么是平衡耳和鼻窦的最好办法？
　　 A: 中耳和鼻窦的气压性创伤是一种常见的由压力增强或者减轻引起的伤害。在水下每下降一英尺，水压就会增加1.5磅，每上升一英尺，则减少相应数量。根据玻意耳定律（Boyle’s Law），当压力上升时，密闭空间内的气体体积会成比例减小，当压力下降时，则相应增大。在下潜的时候，体内有气体的地方主动地或者被动地和外部压力平衡是十分必要的。在浮升的时候，膨胀的气体会自然地释放。
　　 为了能够有效的平衡，你必须没有鼻、鼻窦感染或者过敏反应。鼻、咽和咽鼓管内表面必须非常正常。这样，按照下面的方法你就可以有效的减少中耳和鼻窦阻塞。
　　 * 在下潜前，中性漂浮，排空浮力背心中空气，采用一种下面的方法轻轻地给耳朵充气，这样使你的中耳和鼻窦中在下潜的时候有多余的空气。
　　 * 可能的话，脚向下下潜。这样体内空气会向上向咽鼓管和中耳移动，这是自然的移动方向。使用下潜绳或者锚绳下潜。
　　 * 在前10到15英尺，每隔几英尺轻轻充气。
　　 * 不能有疼痛的感觉。如果有，就说明你没有充分的平衡。
　　 * 如果你觉得耳朵不通畅，停下来，重新尝试，如果还是不行，试着上升几英尺消除压力。但是不要上下窜动。试着把堵塞的耳朵倾斜向上。
　　 * 如果不能平衡的话，就终止潜水。否则不平衡强行下潜也会毁掉潜水旅程，还可能留下永久伤害和造成听力丧失。
　　 * 如果医生同意，你可以在潜水前使用消肿药物或鼻喷剂来减轻鼻部和耳部通道的肿胀。在下潜前1到2小时使用。这些药物的药效可达8到12小时，所以在重复潜水前你不必再次使用。鼻喷剂应该在下潜前半小时使用，药效一般为12个小时。在使用柜台购买的鼻部喷剂要小心。重复使用可能导致堵塞反复、恶化甚至浮升时反方向堵塞。
　　 * 如果在潜水的任何时候，你觉得疼痛、眩晕或者突然听力丧失，终止潜水。如果症状持续，不要重新潜水，去看医生。
　　 * 平衡技巧
　　 * 被动平衡 - 不许任何动作
　　 * 咽鼓管充气法（Valsalva） -捏住鼻子，关闭声（喉）门呼吸以增加鼻咽压力。
　　 * 托因比(Toynbee) - 封闭口鼻，做吞咽动作，这在上升非常有效
　　 * Frenzel - 收缩喉部肌肉，封闭喉门做咽鼓管充气（Valsalva）
　　 * Lowry -咽鼓管充气法（Valsalva）加托因比（Toynbee） - 捏住鼻子，在吞咽的同时轻轻地尝试用鼻子喷气，这是最好也是最简单的方法
　　 * Edmonds - 颌向前伸加上咽鼓管充气法和/或者 Frenzel (好方法)
　　 * 混合方法 - 吞咽，摆动咽喉，在上升时非常有效
　　
　　 Q: What are the best ways to equalize my ears and sinuses?
　　 A: Middle ear and sinus barotrauma are the most common injuries associated with exposure to increasing and decreasing pressure. Descent in the water adds approximately one-half pound of pressure for each foot of descent and diminishes a similar amount on ascent. According to Boyle’s Law, as the pressure increases on descent, the volume of a gas in an enclosed space decreases proportionately. As the pressure decreases on ascent, the volume of the gas increases proportionately. On descent it is imperative that all enclosed air filled spaces be equalized actively or passively. On ascent, the increasing volume usually vents itself naturally.
　　 For equalization to be effective, you should be free of nasal or sinus infections or allergic reactions. The lining of the nose, throat and Eustachian tubes should be as normal as possible. If this is true, the following techniques are effective in reducing middle ear and sinus squeeze.
　　 * Prior to descent, neutrally buoyant, with no air in your buoyancy compensator, gently inflate your ears with one of the techniques listed below. This gives you a little extra air in the middle ear and sinuses as you descend.
　　 * Descend feet first, if possible. This allows air to travel upward into the Eustachian tube and middle ear, a more natural direction. Use a descent line or the anchor line. * Inflate gently every few feet for the first 10 to 15 feet.
　　 * Pain is not acceptable. If there is pain, you have descended without adequately equalizing.
　　 * If you do not feel your ears opening, stop, try again, perhaps ascending a few feet to diminish the pressure around you. Do not bounce up and down. Try to tilt the blocked ear upward.
　　 * If you are unable to equalize, abort the dive. The consequences of descending without equalizing could ruin an entire dive trip or produce permanent damage and hearing loss.
　　 * If your doctor agrees, you may use decongestants and nasal sprays prior to diving to reduce swelling in the nasal and ear passages. Take them one to two hours before descent. They should last from eight to 12 hours so you don’t need to take a second dose before a repetitive dive. Nasal sprays should be taken thirty minutes before descent and usually last twelve hours. Take caution when using over-the-counter nasal sprays. Repeated use can cause a rebound reaction with worsening of congestion and possible reverse block on ascent.
　　 * If at any time during the dive you feel pain, have vertigo (the whirlies) or note sudden hearing loss, abort the dive. If these symptoms persist, do not dive again and consult your physician.
　　 * Equalizing Techniques
　　 * Passive - requires no effort
　　 * Valsalva - increase nasopharynx pressure by holding nose and breathing against a closed glottis (throat)
　　 * Toynbee - swallowing with mouth and nose closed - good for ascent!
　　 * Frenzel - Valsalva while contracting throat muscleswith a closed glottis
　　 * Lowry - Valsalva plus Toynbee - holding nose, gently trying to blow air out of nose while swallowing - easiest and best method!
　　 * Edmonds - jutting jaw forward plus Valsalva and/or Frenzel (good method)
　　 * Miscellaneous - swallowing, wiggling jaws - good for ascent!