Inhaled albuterol, but not intravenous lidocaine, protects against intubation-induced bronchoconstriction in asthma

Abstract

Background: The ability of intravenous lidocaine to prevent intubation-induced bronchospasm is unclear. The authors performed a prospective, randomized, double-blind, placebo-controlled trial to test the ability of intravenous lidocaine and inhaled albuterol to attenuate airway reactivity after tracheal intubation in asthmatic patients undergoing general anesthesia. Methods: Sixty patients were randomized to receive either 1.5 mg/kg intravenous lidocaine or saline, 3 min before tracheal intubation. An additional 50 patients were randomized to receive 4 puffs of inhaled albuterol or placebo 15-20 min before tracheal intubation. Anesthesia was induced with propofol. Immediately after intubation and at 5-min intervals, transpulmonary pressure and airflow were recorded, and lower pulmonary resistance (R(L)) was calculated. Isoflurane was administered after the initial two measurements to assess reversibility of bronchoconstriction. A bronchoconstrictor response to intubation was defined as R(L) greater than or equal to 5 cm H2O · l-1 · s-1 in the first two measurements after intubation and R(L) subsequently decreasing by 50% or more after isoflurane. Results: The lidocaine and placebo groups were not different in the peak R(L) before administration of isoflurane (8.2 cm H2O · l-1 · s-1 vs. 7.6 cm H2O · l-1 · s-1) or frequency of airway response to intubation (lidocaine 6 of 30 vs. placebo 5 of 27). In contrast, the albuterol group had lower peak R(L) (5.3 cm H2O · l-1 · s-1 vs. 8.9 cm H2O · l-1 · s-1; P < 0.05) and a lower frequency of airway response (1 of 25 vs. 8 of 23; P < 0.05) than the placebo group. Conclusions: Inhaled albuterol blunted airway response to tracheal intubation in asthmatic patients, whereas intravenous lidocaine did not.