The Drowning Index: implementation in drowning, mechanical asphyxia, and acute myocardial infarct cases.

Drowning is a diagnosis of exclusion based on circumstantial and autopsy correlation. Sugimura proposed a threshold value of 14.1 for the Drowning Index (DI), the ratio of lung and pleural fluid to spleen weight, as a surrogate marker to diagnose drowning. We questioned the use of DI in diagnosing drowning. We compared DI between three groups--drowning, mechanical asphyxia, and myocardial infarct--seen at Broward MEO from 2008 to 2009. Only 9.4% of 53 drownings exceeded the DI threshold of 14.1, while 30% of 10 mechanical asphyxias and 40% of 10 myocardial infarcts had DI >14.1. Sensitivity for the DI test was <10% and specificity 60-70%. Median DI values for all groups were <10. Mann-Whitney U-test was not statistically significant between groups. The DI is neither sensitive nor specific and lacks any utility in the diagnosis of drowning.