## Algor Mortis: Rate of Body Cooling **Key Point:** Algor mortis (postmortem body cooling) proceeds at approximately **1.5–2.0°F (0.8–1.1°C) per hour** during the first 12 hours after death under standard environmental conditions. ### Factors Affecting the Rate of Algor Mortis | Factor | Effect on Cooling Rate | |---|---| | **Environmental temperature** | Cold environment → faster cooling; warm environment → slower cooling | | **Body composition** | Obese individuals → slower cooling (insulation); lean individuals → faster cooling | | **Clothing & covering** | Insulating layers → slower cooling | | **Cause of death** | Fever/sepsis → initially higher body temperature; hypothermia → already low | | **Air circulation** | Windy conditions → faster cooling | **High-Yield:** The **Henssge nomogram** is used in forensic pathology to estimate the postmortem interval (PMI) based on rectal temperature and ambient temperature. The standard cooling rate of 1.5–2.0°F/hour is the baseline for this calculation. **Clinical Pearl:** After 12 hours, the cooling rate slows as the body temperature approaches ambient temperature (plateau phase). The body does not cool at a constant rate throughout — it follows an exponential decay curve. **Mnemonic:** **ALGOR** = **A**pprox **1.5–2°F/hour** (in first 12 hours) **Warning:** Do not assume the body cools at a constant rate throughout the entire postmortem period. The rate is fastest initially and slows as equilibrium with the environment is approached.
Sign up free to access AI-powered MCQ practice with detailed explanations and adaptive learning.