ABSTRACT
The present study evaluated complement activation during decompression after air dives in a hyperbaric chamber. Intravascular bubbles were quantified by Doppler ultrasound scoring. Eighteen subjects completed 92 dives, of which 74 produced bubbles. Complement activation was assessed by plasma C3a des Arg and red-cell-bound C3d before and after each dive. These parameters of in vivo complement activation failed to show significant activation. In vitro complement activation susceptibility tests on pre-dive sera were performed to explore their association with in vivo complement activation and intravascular bubbles. Such tests failed to identify a distinct complement-sensitive group and did not correlate with in vivo complement activation during the dives and/or intravascular bubble appearance. Two subjects developed decompression sickness but were not different from the rest of the group regarding in vitro complement sensitivity or complement activation during dives.
