Electrocardiographic changes in experimental drowning.

Healthy mongrel dogs were subjected to aspiration of 20 ml/kg of fresh water (group I) or sea water (group II). Fresh water as well as sea water aspiration produced an immediate and significant bradycardia and the heart rate remained appreciably low throughout the forty minute study period. Appearance of tall T waves was the chief electro-cardiographic abnormality seen in both the groups. Out of seven dogs subjected to fresh water aspiration, two died of ventricular fibrillation and the other five survived. On the other hand, out of seven dogs subjected to sea water aspiration, five died of ventricular asystole within 10 min. This shows that equivalent volume of sea water is more lethal than fresh water. Further it is concluded that ventricular fibrillation is common after fresh water aspiration whereas sea water aspiration commonly leads to ventricular asystole.