Research Update: The Effects of Alcohol on Postmortem Bladder Urine Volume

One adverse consequence of the diuretic and impairing effects of alcohol is that there is an increased risk of a painful bladder rupture after minor trauma (e.g., ground level fall, punch to abdomen). One study found that: “Alcohol intoxication increases the risk of bladder rupture by several means. Intoxication decreases the sensation of, and the behavioural response to bladder filling. Both the sheer volume of alcohol and its diuretic effect increases bladder filling, often to the point of massive overdistensions. This overdistension may lead to an atonic decompensated bladder so stretched and thinned that even minor trauma may cause it to rupture.” (WOA40109)

It was originally thought that this type of alcohol-related bladder rupture occurred only in men but another recent study (WOA402U1) reported three women who attended hospital who developed lower abdominal pain after binge drinking. It was later determined that they all had suffered idiopathic rupture of the bladder, highlighting a dangerous and often overlooked outcome of intoxication.

Traditionally, urinary bladder distension at autopsy has been regarded as a sign of intoxication of the deceased, but little scientific studies have been conducted in this area. A recent study, however, has given scientific proof of this observation, specifically linking bladder volume to the effects of alcohol and drugs. The study and citation are:

Rohner, C., S. Franckenberg, N. Schwendener, A. Oesterich, T. Kraemer, M.J. Thali, G.M. Hatch and T.D. Ruder., “New Evidence for Old Lore – Urinary Bladder Distension on Post-Mortem Computed Tomography is Related to Intoxication”, Forensic Science International, 225: 48-52, 2013 [1 table, 5 figures, 17 references]

The bladder urine volume, determined physically at autopsy by the pathologist, was compared with the urine volume calculated by computed tomography (CT) in 259 autopsy cases. Autopsy and toxicology reports in these cases were evaluated to determine if there was any correlation between urine volume at autopsy and alcohol/drug intoxication of the deceased.

The study’s key findings include:

• The mean difference between measured urine volume and CT computed urine volume was only 0.8 mL with a strong correlation (r=0.92).
• The mean volume of urine increased significantly with alcohol/drug intoxication.
• The mean urine volume was greatest in cases where a fatal alcohol/drug intoxication occurred.

The research established critical cutoff volumes:

• Using a 182 mL cutoff showed 40% sensitivity and 87% specificity for detecting intoxication.
• A higher 330 mL cutoff decreased sensitivity to 25% but increased specificity to 97%.

The authors concluded: “We have found that CT provides a reliable method to quantify urinary bladder volume. In our population, there was a statistically significant correlation between urinary bladder distension on the post-mortem CT and cases of intoxication. This means that the occurrence of urinary bladder distension as single finding on post-mortem imaging should raise suspicion of intoxication and result in subsequent toxicological analysis.”

This recent study has shown that the old lore of postmortem urinary bladder distension and alcohol/drug intoxication in the deceased was correct. Postmortem bladder urine volume may provide a preliminary screening tool for the busy pathologist, coroner, medicolegal examiner and forensic toxicology labs. It also may detect cases in which there was no prior suspicion of alcohol /drug intoxication, directly informed by understanding the diuretic effects of alcohol. Of course more research into this area is required, and toxicological findings should not be based on urine volume alone. This study may be obtained at www.sciencedirect.com.

*All the references cited may be found in WOA 2E in the appropriate section according to the number.”