Change in peak expiratory flow rate after the head-tilt/chin-lift maneuver among young, healthy, and conscious volunteers

Objective The head-tilt/chin-lift (HT/CL) is a simple, routinely used maneuver to open the upper airway. Changes in the peak expiratory flow rate (PEFR) before and after the HT/CL maneuver have not been evaluated among conscious volunteers who are regarded as a control cohort. Methods Sixty healthy 20-year-old volunteers (30 males and 30 females) were enrolled. The supine position was defined as the position at which the ear-eye line was at a 10° angle to the horizontal. The HT/CL position was defined as the position at which the ear-eye line was at a 25° angle to the horizontal. PEFR was measured using a hand-held device with the subject in the supine position (pre-PEFR) and HT/CL position (post-PEFR), respectively. One set was defined as these two measurements. Five sets of measurements were performed on each subject (300 sets). The set with the maximal and minimal difference between pre-PEFR and post-PEFR were excluded from the analysis. We used a paired t-test to compare the mean pre-PEFR and post-PEFR values for the entire group and subgroups divided by sex, height, body weight, body mass index and response status. Results Overall, 360 measurements (180 sets) were analyzed. The mean pre-PEFR and post-PEFR were 316.1±87.6 and 346.5±94.7 L/min, respectively. Further, significant differences were observed for sex, height, body weight, and body mass index. In 10 subjects, post-PEFR was lower than pre-PEFR. Conclusion PEFR increased by 9.6% after the HT/CL maneuver in young conscious subjects, but some subjects showed decreased PEFR after the HT/CL maneuver.