The prevention of hypertension at intubation. A controlled study of intravenous hydrallazine on patients undergoing intracranial surgery.

Arterial blood pressure and pulse rate changes following tracheal intubation were studied in 20 patients undergoing intracranial surgery who received a thiopentone/suxamethonium anaesthetic induction sequence. Ten of the patients were pretreated with 0.4 mg/kg of hydrallazine and 10 with saline to determine whether hydrallazine prevents intubation hypertension. The results show that the incidence of intubation hypertension can be reduced using this dose of hydrallazine. Hydrallazine pretreatment is therefore recommended in patients at risk from hypertension following tracheal intubation.