A suitable substitute for 4% cocaine before blind nasotracheal intubation: 3% lidocaine-0.25% phenylephrine nasal spray.

To assess the efficacy of potential substitutes for cocaine as a topical anesthetic before nasal intubation, the authors performed a double-blind study comparing the hemodynamic effects of blind nasotracheal intubation in 75 patients receiving one of three nasal sprays: 4% cocaine (C), a mixture of 3% lidocaine in 0.25% phenylephrine (L-P), and 0.25% phenylephrine alone (P). Three minutes after 0.5 ml of one of the solutions was sprayed into each nostril, anesthesia and paralysis were induced with thiopental (5 mg/kg) followed by succinylcholine (1 mg/kg); immediately after induction, mean arterial pressure (MAP) and heart rate (HR) were recorded. After blind nasotracheal intubation was accomplished, MAP and HR were recorded for 5 min while anesthesia was maintained with 70% N2O in O2. In patients receiving L-P, mean MAP during the 5 min after intubation decreased 2.3 +/- 2.2 mm Hg (mean +/- SEM); this was significantly different from the increase of 6.2 +/- 1.7 and 8.5 +/- 2.0 mm Hg in MAP after intubation of patients receiving C and P, respectively (P less than 0.005). Although mean HR decreased during the 5 min after intubation in all groups, this decrease was significantly greater (9.6 +/- 1.4 beats/min) in patients receiving L-P than in those receiving C (3.1 +/- 1.6 beats/min) or P (0.1 +/- 1.7 beats/min) (P less than 0.005). Changes in HR and MAP were similar in patients receiving C and P. There was no significant difference in the incidence or severity of epistaxis among the three groups.(ABSTRACT TRUNCATED AT 250 WORDS)