721:
181:
in the closed space or by pressure difference hydrostatically transmitted through the tissue. Tissue rupture may be complicated by the introduction of gas into the local tissue or circulation through the initial trauma site, which can cause blockage of circulation at distant sites or interfere with normal function of an organ by its presence.
143:
may induce venous gas bubbles, with a 5% probability of symptoms developing at about 21,200 feet (6,500 m), at which altitude there is over 50% probability of venous bubbles. By 22,500 feet (6,900 m) the incidence of venous bubbles exceeds 70%, with a 55% incidence of DCS. These effects may
85:
Both rate of decompression and pressure difference affect the type of injury likely and the severity of the consequences. Barotrauma is more likely to occur for rapid decompression, while decompression sickness is more likely with a large pressure drop, but both can occur simultaneously. Hypoxia risk
33:
is the reduction in ambient pressure below the normal range of sea level atmospheric pressure. Altitude decompression is hypobaric decompression which is the natural consequence of unprotected elevation to altitude, while other forms of hypobaric decompression are due to intentional or unintentional
180:
Barotrauma is physical damage to body tissues caused by a difference in pressure between a gas space inside, or in contact with, the body, and the surrounding gas or liquid. The initial damage is usually due to over-stretching the tissues in tension or shear, either directly by expansion of the gas
65:
Decompression has physical effects on gas filled spaces and on liquids, particularly when they contain dissolved gases. Physiological effects of decompression are due to these physical effects and the consequential effects on the living tissues, mostly as a result of the formation and growth of
725:
53:
at a lower altitude, or as decompression from an excursion to a lower altitude, in the case of people living at high altitude, making a short duration trip to low altitude, and returning, or a person decompressing from a
120:
due to the naturally low partial pressure of oxygen in the air at altitude. At higher altitudes, more severe, and potentially fatal hypoxia will occur. Decompression sickness and barotrauma are considered aspects of
147:
Altitude decompression sickness often resolves on return to the saturation altitude, but sometimes treatment on elevated concentrations of oxygen is indicated, usually 100% at surface pressure. In more severe cases
144:
be prevented or delayed by more gradual decompression or by flushing some of the nitrogen from the tissues before decompression by prebreathing a high percentage of oxygen before and during decompression.
152:
may be indicated. There is little evidence of altitude decompression sickness occurring among healthy individuals at altitudes below 18,000 feet (5,500 m), but it can occur at lower altitudes in
184:
Decompression may be intentional or uncontrolled. Intentional decompression includes controlled unpressurised ascent to altitude. Uncontrolled decompression is an unplanned drop in the
318:
functions, and eventually death, unless pressure is restored in 60–90 seconds. On Earth, the
Armstrong limit is around 18–19 km (11–12 mi; 59,000–62,000 ft) above
275:, also known as acute mountain sickness (AMS), altitude illness, hypobaropathy, or soroche, is a pathological effect of high altitude on humans, caused by acute exposure to low
66:
bubbles, the expansion of gas filled spaces, and adverse reactions in the injured tissues. Formation and growth of bubbles due to reduced pressure can be due to reduction in
550:
382:
647:
586:
664:
283:
arising from low partial pressure of blood carbon dioxide caused by hyperventilation. Altitude sickness is primarily a consequence of
157:
765:
739:
614:
530:
760:
704:
307:
415:
357:
250:
Rapid decompression may be slow enough to allow cavities to vent but may still cause serious barotrauma or discomfort.
149:
95:
50:
755:
608:"AC 61-107A – Operations of aircraft at altitudes above 25,000 feet msl and/or mach numbers (MMO) greater than .75"
175:
39:
339:
493:
de la Cruz, Richard A.; Clemente
Fuentes, Roselyn W.; Wonnum, Sundonia J.; Cooper, Jeffrey S. (27 June 2022).
471:
607:
556:
388:
335:
303:
134:
105:
101:
59:
331:
280:
122:
730:
523:
310:
is 9 to 12 seconds. Loss of consciousness is due to hypoxia and is followed by a series of changes to
295:
351:
140:
287:. Altitude sickness can be avoided and treated by breathing supplementary oxygen, within limits.
209:
201:
193:
640:
Fundamentals Of
Aerospace Medicine: Translating Research Into Clinical Applications, 3rd Rev Ed
686:
643:
582:
498:
453:
323:
284:
272:
267:
254:
236:
197:
153:
117:
113:
43:
676:
291:
240:
213:
79:
55:
100:
There are three principal physiological effects arising from decompression at altitude:
311:
231:
Explosive decompression (ED) is violent and too fast for air to escape safely from the
189:
139:
Abrupt excursions from sea level to altitudes above 15,000 feet (4,600 m) without
71:
442:"An abrupt zero-preoxygenation altitude threshold for decompression sickness symptoms"
17:
749:
708:
327:
276:
35:
315:
257:
sets in, and is unlikely to cause barotrauma, but may cause decompression sickness.
494:
253:
Slow or gradual decompression occurs so slowly that it may not be sensed before
205:
681:
244:
169:
109:
67:
690:
74:, with nucleation and growth of bubbles in supersaturated liquids, or due to
419:
319:
502:
441:
342:
sets the
Armstrong pressure at an altitude of 63,000 feet (19,202 m).
216:
to vent into its lower-pressure surroundings or fail to pressurize at all.
457:
387:. United States: US Naval Sea Systems Command. p. 61. Archived from
185:
38:
or pressurized compartment, vehicle or habitat, and may be controlled or
27:
Reduction in pressure to lower than normal sea level atmospheric pressure
108:
after exposure to pressures higher than sea level atmospheric pressure,
299:
75:
360: – The physiological basis for decompression theory and practice
555:. United States: US Naval Sea Systems Command. 2006. Archived from
86:
depends mainly on the oxygen partial pressure after decompression.
104:
due to bubble formation in the tissues similar to those caused by
232:
642:. United States: Lippincott Williams And Wilkins. p. 720.
581:(5th Rev. ed.). United States: Saunders Ltd. p. 800.
669:
Continuing
Education in Anaesthesia, Critical Care & Pain
322:, above which atmospheric air pressure drops below 0.0618
579:
Bennett and
Elliott's physiology and medicine of diving
112:
caused by the over-expansion of gas-filled spaces, and
235:
and other air-filled cavities in the body such as the
665:"Humans at altitude: Physiology and Pathophysiology"
354: – Medical treatment at raised ambient pressure
306:. At altitudes above about 50,000 feet (15 km), the
440:Webb, JT; Pilmanis, AA; O'Connor, RB (April 1998).
78:of liquids when the pressure is reduced below the
8:
376:
374:
680:
633:
631:
602:
600:
598:
524:"Altitude-induced Decompression Sickness"
243:, typically resulting in severe to fatal
409:
407:
405:
732:Altitude-induced Decompression Sickness
370:
298:is sufficiently low that exposed water
49:Altitude decompression may occur as a
219:Such decompression may be classed as
7:
577:Brubakk, A.O.; Neuman, T.S. (2003).
42:, or the reduction of pressure in a
663:Brown JP, Grocott MP (2013-02-01).
638:Dehart, R. L.; J. R. Davis (2002).
552:US Navy Diving Manual, 6th revision
384:US Navy Diving Manual, 6th revision
82:for the temperature of the liquid.
70:of dissolved gases as described by
25:
495:"Aerospace Decompression Illness"
158:residual inert gas tissue loading
724: This article incorporates
719:
497:. National Library of Medicine.
740:Federal Aviation Administration
615:Federal Aviation Administration
531:Federal Aviation Administration
340:U.S. Standard Atmospheric model
188:of a sealed system, such as an
34:release of pressurization of a
1:
196:, and typically results from
58:, which is a special case of
51:decompression from saturation
308:time of useful consciousness
358:Physiology of decompression
150:hyperbaric oxygen treatment
96:Physiology of decompression
782:
416:"Human Exposure to Vacuum"
277:partial pressure of oxygen
265:
176:Uncontrolled decompression
173:
167:
132:
93:
682:10.1093/bjaceaccp/mks047
705:"NASAexplores Glossary"
446:Aviat Space Environ Med
31:Hypobaric decompression
766:Decompression practice
726:public domain material
304:human body temperature
135:Decompression sickness
129:Decompression sickness
102:decompression sickness
18:Altitude decompression
381:US Navy (2008). "9".
281:respiratory alkalosis
123:decompression illness
116:, a manifestation of
90:Physiological effects
761:Decompression theory
414:Geoffrey A. Landis.
296:atmospheric pressure
160:after recent diver.
60:diving decompression
352:Hyperbaric medicine
141:oxygen prebreathing
474:. Oxford Reference
194:hyperbaric chamber
756:Aviation medicine
649:978-0-7817-2898-0
588:978-0-7020-2571-6
273:Altitude sickness
268:Altitude sickness
262:Altitude sickness
154:underwater divers
114:altitude sickness
44:hypobaric chamber
16:(Redirected from
773:
743:
737:
723:
722:
713:
712:
707:. Archived from
701:
695:
694:
684:
660:
654:
653:
635:
626:
625:
623:
622:
612:
604:
593:
592:
574:
568:
567:
565:
564:
547:
541:
540:
538:
537:
528:
520:
514:
513:
511:
509:
490:
484:
483:
481:
479:
468:
462:
461:
437:
431:
430:
428:
427:
418:. Archived from
411:
400:
399:
397:
396:
378:
241:eustachian tubes
221:explosive, rapid
202:material fatigue
156:with sufficient
56:dive at altitude
21:
781:
780:
776:
775:
774:
772:
771:
770:
746:
745:
735:
729:
720:
717:
716:
703:
702:
698:
662:
661:
657:
650:
637:
636:
629:
620:
618:
610:
606:
605:
596:
589:
576:
575:
571:
562:
560:
549:
548:
544:
535:
533:
526:
522:
521:
517:
507:
505:
492:
491:
487:
477:
475:
470:
469:
465:
439:
438:
434:
425:
423:
413:
412:
403:
394:
392:
380:
379:
372:
367:
348:
292:Armstrong limit
270:
264:
214:pressure vessel
178:
172:
166:
137:
131:
98:
92:
80:vapour pressure
28:
23:
22:
15:
12:
11:
5:
779:
777:
769:
768:
763:
758:
748:
747:
715:
714:
711:on 2007-09-27.
696:
655:
648:
627:
594:
587:
569:
542:
515:
485:
472:"Prebreathing"
463:
432:
401:
369:
368:
366:
363:
362:
361:
355:
347:
344:
312:cardiovascular
266:Main article:
263:
260:
259:
258:
251:
248:
190:aircraft cabin
168:Main article:
165:
162:
133:Main article:
130:
127:
94:Main article:
91:
88:
26:
24:
14:
13:
10:
9:
6:
4:
3:
2:
778:
767:
764:
762:
759:
757:
754:
753:
751:
744:
741:
734:
733:
727:
710:
706:
700:
697:
692:
688:
683:
678:
674:
670:
666:
659:
656:
651:
645:
641:
634:
632:
628:
616:
609:
603:
601:
599:
595:
590:
584:
580:
573:
570:
559:on 2008-05-02
558:
554:
553:
546:
543:
532:
525:
519:
516:
504:
500:
496:
489:
486:
473:
467:
464:
459:
455:
452:(4): 335–40.
451:
447:
443:
436:
433:
422:on 2009-07-21
421:
417:
410:
408:
406:
402:
391:on 2008-05-02
390:
386:
385:
377:
375:
371:
364:
359:
356:
353:
350:
349:
345:
343:
341:
337:
334:, or about 1
333:
329:
325:
321:
317:
313:
309:
305:
301:
297:
293:
288:
286:
282:
278:
274:
269:
261:
256:
252:
249:
246:
242:
238:
234:
230:
229:
228:
226:
222:
217:
215:
211:
207:
203:
199:
195:
191:
187:
182:
177:
171:
163:
161:
159:
155:
151:
145:
142:
136:
128:
126:
124:
119:
115:
111:
107:
106:decompression
103:
97:
89:
87:
83:
81:
77:
73:
69:
63:
61:
57:
52:
47:
45:
41:
37:
36:pressure suit
32:
19:
731:
718:
709:the original
699:
675:(1): 17–22.
672:
668:
658:
639:
619:. Retrieved
617:. 2007-07-15
578:
572:
561:. Retrieved
557:the original
551:
545:
534:. Retrieved
518:
506:. Retrieved
488:
476:. Retrieved
466:
449:
445:
435:
424:. Retrieved
420:the original
393:. Retrieved
389:the original
383:
316:neurological
289:
271:
224:
220:
218:
212:, causing a
208:failure, or
183:
179:
146:
138:
99:
84:
64:
48:
40:uncontrolled
30:
29:
478:17 December
206:engineering
198:human error
72:Henry's Law
750:Categories
621:2008-07-29
563:2021-12-17
536:2012-02-21
426:2016-02-05
395:2008-06-15
365:References
302:at normal
290:Above the
245:barotrauma
174:See also:
170:Barotrauma
164:Barotrauma
110:barotrauma
68:solubility
691:1743-1816
508:2 October
320:sea level
503:28846248
346:See also
186:pressure
458:9561279
338:). The
285:hypoxia
255:hypoxia
237:sinuses
118:hypoxia
76:boiling
689:
646:
585:
501:
456:
294:, the
210:impact
736:(PDF)
728:from
611:(PDF)
527:(PDF)
330:, 47
326:(6.3
300:boils
233:lungs
223:, or
687:ISSN
644:ISBN
583:ISBN
510:2022
499:PMID
480:2021
454:PMID
332:mmHg
314:and
279:and
239:and
225:slow
677:doi
336:psi
328:kPa
324:atm
192:or
752::
738:.
685:.
673:13
671:.
667:.
630:^
613:.
597:^
529:.
450:69
448:.
444:.
404:^
373:^
227::
204:,
200:,
125:.
62:.
46:.
742:.
693:.
679::
652:.
624:.
591:.
566:.
539:.
512:.
482:.
460:.
429:.
398:.
247:.
20:)
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.