Just at the moment of beginning to breathe aviator's oxygen, a decompression was abruptly started from ground level and continued for 60 minutes at controlled rates ever decreasing but always sufficient to maintain enough calculated nitrogen in either 2000, 3000, or 4000 cubic microns of circulating venous blood to form bubbles of a postulated critical size. Among 44 military men, singly taking 322 flights, there were 20 who never had the joint pain of bends, paresthesia relieved by recompression, nor the distress of chokes. Among the 24 men prone to decompression sickness, when seated comfortably at rest, there was 1 case in 10 Zoom 4000 flights, 12 in 46 Zoom 3000, increasing to 28/79 during Zoom 2000. Marking time at the 29th minute, and thereafter every 5 minutes, increased the ratio to 2/12, 8/24 and 25/39 in Zooms 4000, 3000, and 2000, respectively. It appears that the probability of forming bubbles is much greater when the requisite number of nitrogen molecules are contained in less than 4000 cubic microns of systemic venous blood. For bubbles to form, grow, and evoke symptoms takes more than 24 minutes, all other conditions being constant. Bends resistance may possibly be owing to an instantaneous surface tension greater than 58 dyne/cm. (Author)
Decompression Sickness in Simulated 'Zoom' Flights
1968
8 pages
Report
Keine Angabe
Englisch
Decompression sickness in simulated Apollo space-cabins.
NTRS | 1969
|Elsevier | 1974
Factitious Decompression Sickness
NTIS | 1984
|