Epinephrine, potassium and the electrocardiogram during regional anaesthesia

Abstract

Epinephrine lowers the serum potassium level through an effect on the b 2 -receptor. It is therefore difficult to evaluate whether depression of the ST level and the T wave on the electrocardiogram, during regional anaesthesia, is caused by a high plasma epinephrine level, a low serum potassium level, or both. For this purpose, we studied the relation between electrocardiogram and the plasma epinephrine and serum potassium concentrations during 20 intra-abdominal operations performed under combined epidural and general anaesthesia and in 18 subjects receiving intercostal nerve blockade. The results show that the hypokalaemic effect of epinephrine was reduced when the