Effects of intravenous lidocaine and/or esmolol on hemodynamic responses to laryngoscopy and intubation: a double-blind, controlled clinical trial.
OBJECTIVE
To evaluate the efficacy of intravenous lidocaine and two doses of esmolol for attenuating the cardiovascular responses to laryngoscopy and intubation, and to assess whether a combination of both drugs is more effective than either drug alone.


METHODS
Randomized, prospective, double-blind, placebo-controlled study.


METHODS
University hospital.


METHODS
90 ASA status I and II normotensive women scheduled for elective gynecologic procedures with general anesthesia.


METHODS
Induction of anesthesia was standardized for all patients. The first group received lidocaine 1.5 mg/kg (Group LID); the second and third groups received esmolol 1 mg/kg and 2 mg/kg, respectively (Groups E1 and E2, respectively); the fourth group received lidocaine 1.5 mg/kg and esmolol 1 mg/kg (Group LID-E1); the fifth group received lidocaine 1.5 mg/kg and esmolol 2 mg/kg (Group LID-E2); the sixth group received saline as a placebo (Group PLAC).


RESULTS
Systolic blood pressure and heart rate (HR) were recorded before induction, before injection of the first test drug, immediately before laryngoscopy, and 1, 2, and 5 minutes following intubation. Duration of laryngoscopy was recorded. Only patients receiving placebo had increased HR values after intubation compared with baseline values (p < 0.05). The proportion of patients with a maximum HR exceeding 90 beats/min was significantly higher in the placebo group (8 of 15 patients) than in both esmolol groups (E1 2 of 15; E2 2 of 15) (p < 0.05). Systolic blood pressure values after tracheal intubation did not differ among groups except for those receiving the combinations of lidocaine and esmolol, and they had significantly lower blood pressure (BP) values compared with placebo (p < 0.05).


CONCLUSIONS
Esmolol 1 to 2 mg/kg is reliably effective in attenuating HR response to tracheal intubation. Neither of the two doses of esmolol tested nor that of lidocaine affected the BP response. Only the combination of lidocaine and esmolol attenuated both HR and BP responses to tracheal intubation.
Kindler
C H
CH
Department of Anaesthesia, University of Basel, Switzerland.
Schumacher
P G
PG
Schneider
M C
MC
Urwyler
A
A
D000293:Adolescent; D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use*; D000328:Adult; D000368:Aged; D000779:Anesthetics, Local / Q000008:administration & dosage / Q000627:therapeutic use*; D001794:Blood Pressure / Q000187:drug effects; D004311:Double-Blind Method; D004359:Drug Therapy, Combination; D005260:Female; D005831:Genital Diseases, Female / Q000601:surgery; D006339:Heart Rate / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects*; D006801:Humans; D007275:Injections, Intravenous; D007442:Intubation, Intratracheal / Q000009:adverse effects*; D007828:Laryngoscopy / Q000009:adverse effects*; D008012:Lidocaine / Q000008:administration & dosage / Q000627:therapeutic use*; D008875:Middle Aged; D011412:Propanolamines / Q000627:therapeutic use*; D011446:Prospective Studies
D000319:Adrenergic beta-Antagonists; D000779:Anesthetics, Local; D011412:Propanolamines; D008012:Lidocaine; C036604:esmolol