Effect of body refrigeration on the postmortem formation of gamma hydroxybutyrate in whole blood

Abstract

Gamma hydroxybutyrate (GHB) levels in biological fluids are known to be increased after death. To date, there have been studies on sample storage conditions and preservatives on the postmortem in vitro formation of GHB. However, only few studies explored the effects of body storage conditions on GHB formation after death. In this study, we determined the effect of body refrigeration during body storage in mortuary refrigerators on postmortem formation of GHB in whole blood samples. A total of 41 fatalities were divided into two groups: Group A with a total refrigeration time less than 10 h and Group B with a total body refrigeration time more than 10 h. Femoral blood was collected 3 times: upon arrival at the mortuary, after 4 h of refrigeration, and at autopsy. Rectal temperatures were recorded at the time of specimen collection. Blood GHB concentration was analyzed by LC-MS/MS. The rate of change in GHB levels was calculated. The study revealed that in the later phase of refrigeration, no difference was observed in the blood GHB levels between the two groups despite differences in the postmortem interval (PMI) and refrigeration time. Moreover, the rate of change in the GHB levels was lower in the group with a longer refrigeration time. Hence, we concluded that once the plateau of postmortem GHB formation is reached in a refrigerated body, further formation is not expected even with prolonged PMI. Early body refrigeration can minimize postmortem GHB production, thereby preventing the incorrect interpretation of analytical results.