Effect of chronic nifedipine therapy on the haemodynamic response to phenylephrine before and during halothane anaesthesia.
We evaluated the effect of chronic oral nifedipine therapy (30-80 mg day-1) on the haemodynamic response to the alpha 1-agonist phenylephrine (PE) in 10 patients before and during halothane anaesthesia. The response was compared to a control group of eight patients not taking any cardiovascular drugs. No patients had ganglionic, beta-adrenergic, or muscarinic pharmacological blockade as in prior studies in the literature, and thus had intact cardiovascular reflexes. In all patients, PE caused a dose-related increase in arterial pressure and fall in heart rate and cardiac index. The response in patients taking nifedipine was not significantly different from that measured in controls. One-per-cent halothane in oxygen did not alter the overall haemodynamic response to PE in either group.
Grum
D F
DF
Department of Cardiothoracic Anesthesia, Cleveland Clinic, OH 44106.
Azmy
S S
SS
D000328:Adult; D000769:Anesthesia, Inhalation; D000787:Angina Pectoris / Q000188:drug therapy*; D001026:Coronary Artery Bypass; D005260:Female; D006221:Halothane; D006439:Hemodynamics / Q000187:drug effects* / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009543:Nifedipine / Q000627:therapeutic use*; D010656:Phenylephrine / Q000494:pharmacology*; D013997:Time Factors
D010656:Phenylephrine; D009543:Nifedipine; D006221:Halothane