Effects of nilvadipine on the cardiovascular responses to tracheal intubation.
OBJECTIVE
To evaluate the efficacy of nilvadipine given orally in attenuating the hypertensive response to laryngoscopy and intubation.


METHODS
Controlled, randomized, double-blind study.


METHODS
Induction of anesthesia for elective surgery at a university hospital.


METHODS
Thirty normotensive patients (ASA physical status I) undergoing elective surgery were divided into three groups of ten patients each.


METHODS
Either 2 mg of nilvadipine, 4 mg of nilvadipine, or a placebo (control) was administered orally 90 minutes before induction of anesthesia. Anesthesia was induced with thiopental sodium 5 mg/kg intravenously, and tracheal intubation was facilitated with vecuronium 0.2 mg/kg. During anesthesia, ventilation was assisted or controlled with 1% enflurane and 50% nitrous oxide (N2O) in oxygen. Laryngoscopy lasting 30 seconds was attempted 2 minutes after administration of thiopental sodium and vecuronium.


RESULTS
Patients receiving the placebo showed a significant increase in mean arterial pressure (MAP) and heart rate associated with tracheal intubation. The increase in MAP following tracheal intubation was significantly lower in nilvadipine-treated patients than in the control group (p less than 0.05). However, neither dose of nilvadipine attenuated the tachycardic response to intubation.


CONCLUSIONS
Oral administration of nilvadipine before induction of anesthesia is a simple and practical method for attenuating pressor response to laryngoscopy and tracheal intubation after standard elective induction under additional 1% enflurane-N2O anesthesia.
Mikawa
K
K
Department of Anesthesiology, Kobe University School of Medicine, Japan.
Maekawa
N
N
Hasegawa
M
M
Kaetsu
H
H
Goto
R
R
Yaku
H
H
Obara
H
H
D000284:Administration, Oral; D000328:Adult; D000771:Anesthesia, Intravenous; D001794:Blood Pressure / Q000187:drug effects* / Q000502:physiology; D002121:Calcium Channel Blockers / Q000008:administration & dosage / Q000627:therapeutic use*; D004311:Double-Blind Method; D004562:Electrocardiography / Q000187:drug effects; D005260:Female; D006339:Heart Rate / Q000187:drug effects* / Q000502:physiology; D006801:Humans; D006973:Hypertension / Q000517:prevention & control; D007442:Intubation, Intratracheal / Q000009:adverse effects; D007828:Laryngoscopy / Q000009:adverse effects; D008297:Male; D008875:Middle Aged; D009543:Nifedipine / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000627:therapeutic use; D010919:Placebos; D011292:Premedication; D013610:Tachycardia / Q000517:prevention & control; D013874:Thiopental; D014673:Vecuronium Bromide
D002121:Calcium Channel Blockers; D010919:Placebos; C035100:nilvadipine; D014673:Vecuronium Bromide; D009543:Nifedipine; D013874:Thiopental