RESUMO
BACKGROUND: Intravenous alfentanil is one of the effective methods to minimize the hemodynamic responses to laryngoscopy and endotracheal intubation. The purpose of this study is to get effective dose (ED50, ED95) of alfentanil to minimize the hemodynamic responses to laryngoscopy and endotracheal intubation. METHODS: Sixty patients were divided into four groups. Each group received intravenous normal saline 5 ml (Control group), alfentanil 10microgram/kg (Al10), alfentanil 20microgram/kg (Al20) and alfentanil 30microgram/kg (Al30), respectively. Mean arterial pressure (MAP) and heart rate (HR) were measured before and after intubation. We considered the doses of alfentanil effective when the increase in MAP and HR after intubation did not exceed 10% of those before intubation. RESULTS: The ED50 of alfentanil was 12.7 (8.6-16.4)microgram/kg for MAP, 20.1 (15.7-25.6)microgram/kg for HR, respectively. The ED95 of alfentanil was 26.4 (21.7-36.2)microgram/kg for MAP, 38.6 (31.2-56.7)microgram/kg for HR, respectively. CONCLUSIONS: Alfentanil was effective to minimize the hemodynamic responses to laryngoscopy and endotracheal intubation with its ED50 and ED95 as mentioned earlier.
Assuntos
Humanos , Alfentanil , Pressão Arterial , Frequência Cardíaca , Hemodinâmica , Intubação , Intubação Intratraqueal , LaringoscopiaRESUMO
BACKGROUND: Induction of anesthesia with a high dose of fentanyl and vecuronium decreases the heart rate and blood pressure. This study was designed to evaluate the effect of preinduction atropine on these hemodynamic changes in patients undergoing coronary artery bypass graft surgery (CABG). METHODS: Forty-one patients who underwent CABG were randomly divided into two groups. After insertion of a radial artery cannula and a Swan-Ganz catheter, normal saline 1 ml (control group, n = 20) or atropine 0.5 mg (atropine group, n = 21) was injected intravenously 1 min before the induction of anesthesia. Anesthesia was induced with a first dose of fentanyl (5-8 microgram/kg) and vecuronium (0.12 mg/kg) and a second dose of fentanyl (5-10 microgram/kg). The patient was then intubated. Hemodynamic variables were measured before the induction of anesthesia, 1 min after the administration of each drug during the induction of anesthesia and 5, 10, and 30 min after the intubation. RESULTS: There was no significant differences between the two groups in terms of demographic data except that the number of patients with diabetes mellitus was greater in the control group than in the atropine group. The number of patients treated for hypotension or bradycardia during the induction of anesthesia was greater in the control group than in the atropine group, but this was not statistically significant. Heart rates significantly decreased in the control group but were maintained in the atropine group without any significant tachycardia. Blood pressure significantly decreased in both groups. CONCLUSIONS: Intravenous injection of atropine before anesthetic induction in patients undergoing CABG attenuates the decrease in heart rate resulting from anesthetic induction with high dose fentanyl and vecuronium. However, it didn't prevent the decrease in blood pressure nor did it reduce the incidence of treatment for hypotension.
