Effects of postmortem interval and cause of death on organ weights

Context: Visceral congestion is a characteristic autopsy finding of some causes of death, and the congestion changes the organ weight. Therefore, comparing the measured organ weights against standards can provide useful information. Aim: We sought to generate accurate organ weight standards according to the postmortem interval (PMI) and the cause of death, with particular focus on brain and lung weights. Settings and Design: Retrospective study. Cadavers and Methods: We included data from 489 (320 males and 169 females) forensic autopsy cases with known PMIs; within 4 days. We considered gender, age, height, body weight and PMI in our organ weight estimations. In addition, we used longitudinal (243 males and 131 females) and transverse (243 males and 130 females) skull diameters in constructing an equation for brain weight estimation. Statistical Analysis Used: Chi-square test, Welch's t-test and stepwise regression analysis. Results: Causes of death such as intracranial injury and bleeding, intoxication and drowning tended to increase lung weight; other causes tended to decrease lung weight. When we focused on cases with 1-day PMI, the brain and lung weights increased with longer PMIs, probably due to the brain oedema and pulmonary congestion and oedema in the early post-mortem period. Conclusion: Ours was the first report on the increase of brain weight with the increase of PMI in the early postmortem period. Further studies on the effects of PMI and the cause of death on organ weight are required to expand our understanding on the mechanisms of death.