The Flow-Pressure and Cardiopulmonary Responses of Manual Chest Percussion with Different Ranges of Oscillation Frequency in Healthy Subjects

Abstract

Manual chest wall percussion (MP) is a technique for secretion clearance which commonly use. However, MP is performed by physiotherapists throughout a broad range of the oscillation frequency, which might result in different physical properties and cardiopulmonary responses of MP. Investigate the flow, pressure and cardiorespiratory response during MP with 3 frequencies in healthy subjects. Twenty-one healthy subjects (8 men and 13 women) were recruited into this crossover study. MP was applied with 3 frequency ranges, including low (4.0 ± 0.5), medium (5.5 ± 0.5), and high (6.5 ± 0.5) Hz, for 3 min in the neutral side lying on left side. A flow sensor (Model SS11LA) and a pressure sensor (Model SS13L) were used to measure Inspiratory-expiratory (I-E) flow rate and pressure through mouth. A bedside monitor (BSM 2351k, Nihon Kohden) was used to measure cardiopulmonary response. All dependent variables were measured pre-(resting), during, and post-(recovery) MP application. Both I-E flow rate and pressure were increased from resting significantly in all frequencies MP, but they were not different among the 3 frequency ranges. The E flow rate was increased to 0.41-0.44, 0.49-0.52 and 0.41-0.49 L/s (min-max) during MP application at low, medium, and high frequency compared to resting (0.31-0.36 L/s), respectively. The E pressure was increased to 0.40-0.41, 0.44-0.47 and 0.39-0.47 cmH2O (min-max) during MP application at low, medium, and high frequency compared to resting (0.20-0.22 cm H2O), respectively. However, the increment of the 3 frequency ranges did not affect the cardiovascular functions except respiratory rate, which was increased only 2 breaths/min from resting. In conclusion, airflow and pressure were slightly increased during MP but did not affect cardiopulmonary functions in healthy subjects. Further study in patients is needed.