Variability in antemortem and postmortem blood alcohol concentration levels among fatally injured adults

Abstract

Background: Excessive alcohol use is a risk factor for injury-related deaths. Postmortem blood samples are commonly used to approximate antemortem blood alcohol concentration (BAC) levels.Objectives: To assess differences between antemortem and postmortem BACs among fatally injured adults admitted to one shock trauma center (STC).Method: Fifty-two adult decedents (45 male, 7 female) admitted to a STC in Baltimore, Maryland during 2006-2016 were included. STC records were matched with records from Maryland's Office of the Chief Medical Examiner (OCME). The antemortem and postmortem BAC distributions were compared. After stratifying by antemortem BACs <0.10 versus ≥0.10 g/dL, differences in postmortem and antemortem BACs were plotted as a function of length of hospital stay.Results: Among the 52 decedents, 22 died from transportation-related injuries, 20 died by homicide or intentional assault, and 10 died from other injuries. The median BAC antemortem was 0.10 g/dL and postmortem was 0.06 g/dL. Thirty-one (59.6%) decedents had antemortem BACs ≥0.08 g/dL versus 22 (42.3%) decedents using postmortem BACs. Postmortem BACs were lower than the antemortem BACs for 42 decedents, by an average of 0.07 g/dL. Postmortem BACs were higher than the antemortem BACs for 10 decedents, by an average of 0.06 g/dL.Conclusion: Postmortem BACs were generally lower than antemortem BACs for the fatally injured decedents in this study, though not consistently. More routine antemortem BAC testing, when possible, would improve the surveillance of alcohol involvement in injuries. The findings emphasize the usefulness of routine testing and recording of BACs in acute care facilities.

Keywords: Alcohol; binge drinking; blood alcohol concentration (BAC); deaths; injury.

Fig. 1.

Process for deriving study sample of fatally injured adult decedents with reported blood alcohol concentration (BAC) data from the R Adams Cowley Shock Trauma Center (STC) and Maryland’s Office of the Chief Medical Examiner (OCME) in Baltimore, Maryland, 2006–2016.

Fig. 2.

Distribution of antemortem and postmortem blood alcohol concentration (BAC) levels among the 52 fatally injured adult decedents in the study sample. The overall distribution of postmortem BACs was lower than the distribution of antemortem BACs, with 19 (36.5%) decedents having a postmortem BAC of 0.00–0.05 g/dL compared with 8 (15.4%) decedents being within this range based on antemortem BACs.

Fig. 3.

Individual level differences in postmortem blood alcohol concentration (BAC) relative to antemortem BAC among the fatally injured adult decedents in the study sample. Among decedents with an antemortem BAC <0.10 g/dL (n = 26) (Figure 3a) and decedents with an antemortem BAC ≥0.10 g/dL (n = 26) (Figure 3b), decedents with a longer length of hospital stay had a greater BAC difference postmortem relative to antemortem.