The influence of the halothane test on heart parameters, OCT-activity, acid-base balance and blood electrolytes in halothane-sensitive pigs and in pigs premedicated with a beta-blocker (propranolol).

The heart and liver functions, blood electrolytes and acid-base balance were studies in halothane-sensitive and nonsensitive pigs. An inhibition of the hyperthermia reaction was attempted by an i.v. injection of propranolol. The pulse rate of sensitive pigs was shown to be elevated already at the beginning of halothane narcosis. No other differences between sensitive and nonsensitive pigs were observed from the electrocardiogram. Ectopic beats and arythmia appeared only in 1 halothane-sensitive pig which died soon after the test. The serum OCT-activity showed no abnormalities. Hyperkalemia and acidosis occurred but the Ga was not elevated in halothane-sensitive animals. The slight elevation in Na was thought to be caused by hemoconcentration. A propranolol injection only delayed but did not inhibit the halothane reaction.