The electrocardiogram of rabbits in blast injury.

Summary. 1. The ECG changes in blast injury have been studied in 194 rabbits, 62 of which were exposed to a detonating charge of TNT in the open field and the remaining 132 animals to a charge of PETN in a specially constructed detonation chamber. 2. In the total material 65.5 per cent showed pathological ECG after the detonation, in the open field material 30.6 per cent and of the rabbits exposed in the detonation chamber 81.8 per cent. An inetantaneous, transient and often pronounced sinus brady cardia and a lowering of the voltage are found in almost every case, but these changes are not included in the pathological changes. 3. Premature beats, depression of RS—T and T, injury potential, different kinds of heart block and auricular fibrillation are rather common findings. 4. Some changes in ECG are not manifested until several minutes to some days after the detonation, and some are only of a transient type. The changes in the first stages after the detonation often differ from those occurring later on.