Platelet count in deep saturation diving

Platelet counts were measured in 10 divers during the course of 4 experimental deep dives (450 and 600 m) and different anticoagulants were tested. The use of sodium citrate as an anticoagulant was associated with artifactual thrombocytopenia, whereas ethylenediaminetetraacetic acid proved to be satisfactory. During one of the dives (450 m) the use of fluorocarbon to remove excess dissolved inert gas before decompression of the samples was systematically tested. Mean platelet count decreased from 272,600 +/- 29,400 mm-3 (mean +/- SD) on Day 7 (450 m) to 177,700 +/- 26,400 mm-3 on Day 12 (360 m). Platelet count had recovered to 209,900 +/- 20,700 mm-3 at the time of surfacing. Mean hematocrit (expressed in percent) increased from 44.7 +/- 2.2 predive to 59.4 +/- 2.0 on Day 7 (450 m) to 40.9 +/- 2.8 at the time of surfacing. These changes were statistically significant (P less than 0.05). Platelet counts on samples that had been degassed with fluorocarbon were not different from samples that had been decompressed without degassing.