Fu S Xue1, He P Liu, Nong He, Ya C Xu, Quan Y Yang, Xu Liao, Xiu Z Xu, Xin L Guo, Yan M Zhang. 1. Department of Anesthesiology, Plastic Surgery Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, 33 Ba-Da-Chu Rd, Shi-Jing-Shan District, Beijing, People's Republic of China 100144. fruitxue@yahoo.com.cn
Abstract
BACKGROUND: We designed this randomized, double-blind clinical study to compare the safety and efficacy of 2% and 4% lidocaine during airway topical anesthesia with a spray-as-you-go technique via the fiberoptic bronchoscope. METHODS:Fifty-two adult patients with a difficult airway were randomly assigned to 1 of 2 study groups to receive 2% (Group 1) or 4% lidocaine (Group 2) by a spray-as-you-go technique with the fiberoptic bronchoscope, in a double-blind manner. After airway topical anesthesia, awake fiberoptic orotracheal intubation (FOI) was performed. Level of sedation, time for each lidocaine spray in different targeted areas, total times for airway sprays, total dosages of lidocaine used for airway sprays, intubation times, and number of intubation attempts were noted. An independent investigator scored patients' comfort during airway topical anesthesia, patients' reaction, coughing severity, and intubating condition during awake FOI, and observed changes of arterial blood pressure and heart rate during each stage in the airway manipulation process. Serial blood samples were obtained for analysis of plasma lidocaine concentrations. RESULTS: Except for the total dosages and plasma concentrations of lidocaine, there were no significant differences in any of the observed variables between groups. All patients exhibited excellent or acceptable intubating conditions. The total dosages of lidocaine were significantly smaller in Group 1 (3.4 +/- 0.6 mg/kg) than in Group 2 (7.1 +/- 2.1 mg/kg). The plasma lidocaine concentrations in all observed points after the supraglottic sprays were larger in Group 2 than in Group 1. CONCLUSIONS: Both 2% and 4% lidocaine administered topically by a spray-as-you-go technique can provide clinically acceptable intubating conditions for awake FOI in sedated patients with a difficult airway. As compared with 4% lidocaine, however, 2% lidocaine requires a smaller dosage and results in lower plasma concentrations.
RCT Entities:
BACKGROUND: We designed this randomized, double-blind clinical study to compare the safety and efficacy of 2% and 4% lidocaine during airway topical anesthesia with a spray-as-you-go technique via the fiberoptic bronchoscope. METHODS: Fifty-two adult patients with a difficult airway were randomly assigned to 1 of 2 study groups to receive 2% (Group 1) or 4% lidocaine (Group 2) by a spray-as-you-go technique with the fiberoptic bronchoscope, in a double-blind manner. After airway topical anesthesia, awake fiberoptic orotracheal intubation (FOI) was performed. Level of sedation, time for each lidocaine spray in different targeted areas, total times for airway sprays, total dosages of lidocaine used for airway sprays, intubation times, and number of intubation attempts were noted. An independent investigator scored patients' comfort during airway topical anesthesia, patients' reaction, coughing severity, and intubating condition during awake FOI, and observed changes of arterial blood pressure and heart rate during each stage in the airway manipulation process. Serial blood samples were obtained for analysis of plasma lidocaine concentrations. RESULTS: Except for the total dosages and plasma concentrations of lidocaine, there were no significant differences in any of the observed variables between groups. All patients exhibited excellent or acceptable intubating conditions. The total dosages of lidocaine were significantly smaller in Group 1 (3.4 +/- 0.6 mg/kg) than in Group 2 (7.1 +/- 2.1 mg/kg). The plasma lidocaine concentrations in all observed points after the supraglottic sprays were larger in Group 2 than in Group 1. CONCLUSIONS: Both 2% and 4% lidocaine administered topically by a spray-as-you-go technique can provide clinically acceptable intubating conditions for awake FOI in sedated patients with a difficult airway. As compared with 4% lidocaine, however, 2% lidocaine requires a smaller dosage and results in lower plasma concentrations.
Authors: J Adam Law; Natasha Broemling; Richard M Cooper; Pierre Drolet; Laura V Duggan; Donald E Griesdale; Orlando R Hung; Philip M Jones; George Kovacs; Simon Massey; Ian R Morris; Timothy Mullen; Michael F Murphy; Roanne Preston; Viren N Naik; Jeanette Scott; Shean Stacey; Timothy P Turkstra; David T Wong Journal: Can J Anaesth Date: 2013-10-17 Impact factor: 5.063