Lung and Pleural Effusion/Height as useful Index in Drowning Death Diagnosis

Drowning under drug influence is scarcely reported, especially in relation to lung weight in drug-free or drug-positivity drowning. A novel drowning index is proposed in order to easily compare some factors (drug exposure, fresh/salty water, gender, age, post-mortem interval) acting on drowning deaths. Autopsies and toxicological analyses were performed in 48 drowning cases. Ultra-high-performance liquid chromatography-tandem mass spectrometry for drugs of abuse and headspace-gas chromatography-mass spectrometry GC-MS for volatile substances resulted in positive on 13 cases. The drug-positive group was compared to the drug-free group thanks to a novel drowning index [(lungs plus pleural effusion) / height]. Salty/freshwater, sex, and age influence were studied in the two groups to detect their influence on the novel drowning index. Bromazepam, ethanol, lorazepam, lormetazepam, ethanol plus cocaine were quantified in 13/48 drowning cases. In the univariate analysis, the variables associated with low drowning index were female gender (p = 0.010), freshwater drowned (p = 0.012), and benzodiazepine assumption (p = 0.012). Drowning under ethanol effect compared to drug-free cases did not obtain significant associations. In the multivariate analysis, only the male gender (β = -0.378, p = 0.005) and salty water (β = 0.369, p = 0.006) were independent parameters associated with higher DI (adjusted R2 = 0.241). Comparison between groups of drowning can take advantage of an integrated drowning index that, thanks to its sensibility, can register differences induced by the type of water & intake of exogenous substances & age/sex.