Truview EVO2 and standard Macintosh laryngoscope for tracheal intubation during cardiopulmonary resuscitation: a comparative randomized crossover study.

The aim of this study was to compare the performance of the Truview EVO2 laryngoscope in manikin-simulated cardiopulmonary resuscitation (CPR) and no-CPR scenarios with standard intubation technique. Participants performed 4 scenarios in random order: endotracheal intubation (ETI) using Macintosh laryngoscope (MCL), Truview EVO2 laryngoscope in no-CPR patient scenario, and intubation during uninterrupted chest compressions using both laryngoscopes. The participants were directed to make 3 attempts in each scenario. Primary outcomes were time to tracheal intubation (TTI) and intubation success, whereas secondary outcomes were cumulative success ratio and the number of esophageal intubation (EI). TTI and success ratios were reported per attempt. Thirty paramedics completed the study. Median TTI with Truview EVO2 with CPR was 36 (interquartile range [IQR] 29.00-52.00), 22.5 (IQR 18.33-35.00), and 18 (IQR 11.00-23.00) seconds; MCL with CPR was 23 (IQR 18.92-36.90), 16.8 (IQR 14.00-22.31), and 14.5 (IQR 11.12-16.36) seconds; Truview EVO2 without CPR was 28.6 (IQR 24.02-38.34), 21.7 (IQR 17.00-25.00), and 13 (IQR 11.90-17.79) seconds; MCL without CPR was 17 (IQR 13.23-22.29), 13 (IQR 12.09-15.26), and 12.4 (IQR 10.08-19.84) seconds for first, second, and third attempts, respectively. The P values for differences in TTI between Truview EVO2 and MCL were P < 0.0001, P = 0.0540, and P = 0.7550 in CPR scenario and P = 0.0080, P = 0.1570, and P = 0.7652 in no-CPR scenario for first, second, and third attempts, respectively. The success ratios for each of the scenarios were as follows: in CPR scenario it was 0.73 versus 0.53 (P = 0.0558), 0.83 versus 0.76 (P = 0.2633), and 1 versus 0.8 (P = 0.0058); in no-CPR scenario it was 0.63 versus 0.73 (P = 0.2068), 0.86 versus 0.86, and 0.97 versus 1 (P = 0.1637) for Truview EVO2 vs MCL in first, second, and third attempts, respectively. The cumulative success ratio related to the time of ETI was better for MCL compared with Truview EVO2 laryngoscope in both scenarios (P = 0.0029 and P = 0.0004 in no-CPR and CPR scenarios). The number of EI with MCL was 30% versus 13.3% (P = 0.0113), and for Truview EVO2 it was 20.45% versus 15.56% in CPR and no-CPR scenarios, respectively. The application of Truview EVO2 during uninterrupted chest compressions increased TTI but increased the success ratio of ETI and decreased number of EIs.