Decrease in platelet count during saturation diving
Domoto, H.; Nakabayashi, K.; Hashimoto, A.; Suzuki, S.; Kitamura, T.
Aviation Space and Environmental Medicine 72(4): 380-384
2001
ISSN/ISBN: 0095-6562 PMID: 11318019 Document Number: 538151
Background: The change in platelet count (PC) occurring during saturation diving has rarely been discussed. We set out to clarify the details of this change in PC, and its relationship with: i) the storage depth and duration of the saturation dive, and ii) the presence of decompression bubbles. Methods: In a total of 42 divers, the change in PC was measured in 8 simulated saturation dives (1992-1998) using a Deep Diving Simulator with decompression procedures based on the modified DUKE-GKSS schedule. Blood samples were taken before the dive, at the bottom (twice), during decompression, on surfacing, and about 1 wk after surfacing. Decompression bubbles were examined by ultrasonic M-mode echocardiography. Results: PC (mean +- SD X 104 cntdot mul-1) was 23.9 +- 4.85, 24.9 +- 4.9, 24.2 +- 4.8, 19.2 +- 4.4*, 20.1 +- 4.5*, 25.0 +- 5.1 on the occasions listed above (*= p < 0.05 vs. pre-dive). The PC showed no correlation with either storage depth or dive duration. Decompression bubbles were detected during decompression in only 2 divers (4.8%), and the bubbles disappeared immediately after surfacing. In these 2 divers the decreases in PC values from baseline to the middle of decompression and on surfacing were 2 and 2.7 X 104 cntdot mul-1, and 3.4 and 1.7 X 104 cntdot mul-1 respectively. No diver complained of decompression sickness. Conclusion: The magnitude of the decrease in PC (< 5 X 104 X mul-1) and the time to recover to the pre-dive value (< 1 wk) suggests that changes in PC during saturation diving should not cause any clinical problems. The mechanisms underlying the decrease in PC remain unclear.