[abstract] TRANSIENT REDUCTION OF PLATELETS AFTER INITIATING HBO

Abstract

BACKGROUND: Most literature supports the hypothesis that platelet count values (PLT-cv) vary during acute hyperbaric oxygen therapy (HBOT). In this study, we evaluate a number of blood parameters to determine which, if any, could both identify a measurable, causal effect secondary to the application of HBOT and be significantly predictive of the anticipated clinical outcomes. MATERIALS AND METHODS: Using a low-cost research design, we recently evaluated a large amount of previously unscreened data. Daily monitoring of patients afforded us the opportunity to monitor PTL-cv T in 12 patients under the following conditions: before patient access to the Diving and Hyperbaric Medicine Unit (Tx #0), during initial treatment (Tx #1-5), and after additional HBOT (Tx #14-20), as applicable. The treatment group included an equal number of male and female subjects (ages 45-84 yo), 8 of them suffering from acute CO poisoning and 4 from vascular insufficiency. RESULTS: An initial decrement in PTL-cv from baseline was seen (15.20-42.45% by Tx 1-5). This was followed by a rise in PLT-cv to normal values by approximately treatment #7. Subsequently, a sudden, sharp increase in PLT-cv was seen at the final tested condition (Tx #14-20), with elevation over baseline averaging •21.08%. Notably, higher platelet elevations were associated with worse treatment outcomes. CONCLUSIONS: Our observational findings demonstrate a biphasic response of PTL-cv during HBOT. The initial and transient platelet reduction (probably due to HBOT-mediated, medullary-inhibition at the very first stage of the treatment) was followed later by an absolute increase in PLT-cv. Although this limited, observational data suggests a biphasic pattern of platelet behavior in response to HBOT, a multi-center trial with detailed analysis of PLT-cv and complete blood counts would be necessary to properly evaluate our preliminary findings and fully characterize this intriguing hypothesis.