The effects of lidocaine and fentanyl on airway irritability during inhalation induction with desflurane / 대한마취과학회지

BACKGROUND: Inhalation induction with desflurane can cause airway irritability and sympathetic stimulation. The aim of this study was to investigate whether lidocaine and fentanyl could reduce these unwanted reactions. METHODS: Seventy-five patients who had premedication with midazolam were randomly allocated to one of three groups to receive intravenous saline (S group), lidocaine 1.5 mg/kg (L group), fentanyl 1 microgram/kg (F group), respectively, before tidal volume induction with desflurane in oxygen and nitrous oxide. We recorded airway irritability such as cough, apnea, laryngospasm and excitatory movement and hemodynamic changes. RESULTS: Airway irritability was not significantly different between the groups. In F group, mean blood pressure at LOC ver and LOC BIS and heart rate at LOC ver, LOC BIS and just before intubation were lower than those of S group (P < 0.05). Other results were not significantly different. CONCLUSIONS: The results of the study showed that intravenous fentanyl and lidocaine had no beneficial effects to reduce airway irritability, but intravenous fentanyl could significantly reduce hemodynamic stimulation during inhalation induction with desflurane in the patients who were premedicated with midazolam.

The Effects of Intravenous Lidocaine and Alfentanil on Airway Irritability and Hemodynamic Stability during Inhaled Induction with Desflurane: A Randomized Double-Blinded Studdy / 대한마취과학회지

BACKGROUND: Because desflurane can cause airway irritability when used to induce anesthesia, drugs aimed at reducing airway irritability. This study investigated the possible differences between lidocaine and alfentanil on the decrease in the airway irritability during desflurane inhaled induction. METHODS: 75 patients (25 in each groups) were assigned randomly to induce anesthesia with inhaled desflurane. The breathing circuit was primed with desflurane 6% in 50% O2 and 50% N2O. After pretreatment with 2% lidocaine (1 mg/kg), or alfentanil (10microgram/kg), or saline (7 ml) intravenously 2 minutes before inducing anesthesia, each patient breathed the gas mixture through a tight fitting facemask. The time to loss of consciousness, cough, laryngospasm, excitatory movement and hemodynamics were checked before and after inhalation. RESULTS: The time to loss of consciousness, cough and excitatory movement were lower significantly between in the control group and other groups, but there was no difference between the 2% lidocaine and alfentanil groups. The blood pressure and heart rate were lower in the alfentanil group, but the heart rate was similar. CONCLUSIONS: These results explain that intravenous 2% lidocaine appears to be useful. However, Intravenous alfentanil can also reduce the airway irritability and stabilize the hemodynamics significantly when desflurane is used to induce anesthesia.