Dive_Man_ChangeA

14-14 Change A U.S. Navy Diving Manual—Volume 3 times on air by tripling the remaining oxygen time at each stop. See paragraph 14-4.4 for an example. 14-4.10 Oxygen Convulsion at the 30 and 20 fsw Water Stop. If symptoms progress to an oxygen convulsion despite the above measures, a serious emergency has devel- oped and the following actions must be taken. 1. Shift both divers to air and follow the guidance given in paragraph 14-4.8 for stabilizing the diver and determining whether he is breathing. 2. If the diver is breathing, hold him at depth until he is stable, then surface decompress. 3. If surface decompression is not feasible, ventilate both divers with air and complete decompression in the water on air. Compute the remaining stop times on air by tripling the remaining oxygen time at each stop. See paragraph 14-4.4 for an example. 4. If the diver is not breathing, surface the diver at 30 fsw/min while maintaining an open airway and treat the diver for arterial gas embolism (Figure 21-5). 14-4.11 Oxygen Toxicity Symptoms in the Chamber. At the first sign of CNS oxygen toxicity, the patient should be removed from oxygen and allowed to breathe chamber air. Fifteen minutes after all symptoms have completely subsided, resume oxygen breathing at the point of interruption. If symptoms of CNS oxygen toxicity develop again or if the first symptom is a convulsion, take the following action: 1. Remove the mask. 2. After all symptoms have completely subsided, decompress 10 feet at a rate of 1 fsw/min. For a convulsion, begin travel when the patient is fully relaxed and breathing normally. 3. Resume oxygen breathing at the shallower depth at the point of interruption. 4. If another oxygen symptom occurs, complete decompression on chamber air. Follow the guidance given in paragraph 14-4.5 for permanent loss of chamber oxygen supply to compute the air decompression schedule. 14-4.12 Asymptomatic Omitted Decompression. Certain emergencies may interrupt or prevent required decompression. Unexpected surfacing, exhausted gas supply and bodily injury are examples of such emergencies. Table 14-2 shows the initial management steps to be taken when the diver has an uncontrolled ascent. 14-4.12.1 Blowup from a Depth Greater Than 50 fsw. Blowup from a depth greater than 50 fsw when more than 60 minutes of decompression are missed is an extreme emer- gency. The diver shall be returned as rapidly as possible to the full depth of the dive or the deepest depth of which the chamber is capable, whichever is shallower.