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Cardiac blood pH as a possible indicator of postmortem interval
W R Sawyer1, D R Steup, B S Martin
1Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis.
Journal of Forensic Sciences
|November 1, 1988
Summary
Postmortem blood pH reliably decreases over time in rats, regardless of sacrifice method. Human autopsy data suggests a similar trend, indicating pH as a potential postmortem interval indicator.
Area of Science:
- Forensic Science
- Physiology
- Biochemistry
Background:
- Understanding postmortem changes is crucial for forensic investigations.
- Blood pH alterations after death can provide insights into the time elapsed since demise.
Purpose of the Study:
- To investigate postmortem blood and tissue pH changes in rats over an extended period.
- To explore the correlation between cardiac blood pH and postmortem interval in humans.
Main Methods:
- Rats were analyzed for blood and tissue pH at various postmortem intervals (2 min to 96 h).
- Cardiac blood pH was measured in human autopsy cases (n=11) with known postmortem intervals (2-20 h).
Main Results:
- Rat cardiac blood pH showed a significant and consistent decrease across all postmortem intervals and sacrifice methods.
- A strong negative correlation (r = -0.908, P < 0.01) was observed between human cardiac blood pH and postmortem interval.
Conclusions:
- Cardiac blood pH is a reliable indicator of postmortem changes in rats.
- The findings suggest that cardiac blood pH may serve as a valuable biomarker for estimating the postmortem interval in humans.
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