Objectives: The objective of this study was to evaluate the effects of mechanical insufflation-exsufflation (MI-E) on volume change of the chest wall and each compartment of the chest wall in patients with cervical spinal cord injury using optoelectronic plethysmography (OEP).
Fourteen male patients with chronic cervical spinal cord injuries were included. Each subject was instructed to lie on a bed in the supine position and 45 reflective markers were placed on predetermined locations on the chest wall. The respiratory movements were recorded by a 3D optoelectronic motion analysis system (Vicon MX; Vicon Motion Systems, Oxford, UK) with 6 infrared cameras placed around the subject. The subjects were asked to take deep breath (vital capacity measurement maneuver).Then, we applied MI-E through face mask at the pressure of ±30, 40, 50 cmH2O. The following parameters were calculated from the saved 3D coordinate data of the reflective markers; change of the total volume of the chest wall and the compartmental volume of the upper thorax, lower thorax and abdomen.
The change of chest wall volume was significantly greater during MI-E of ≥±30 cmH2O than when taking a deep breath. The volume change in the upper and lower thorax compartment was significantly greater during MI-E of ≥±30 cmH2O than when taking a deep breath. However, MI-E made no significant difference to the volume of the upper and lower thorax compartment between pressures of ±30 cmH2O and ±50 cmH2O. The volume change in the abdomen compartment was slightly greater during MI-E than when taking a deep breath, but this was not statistically significant.
Kozo Hanayama– Professor, Department of Rehabilitation Medicine, Kawasaki Medical School
Takefumi Sugiyama– Associate Professor, Department of rehabilitation Medicine, Kawasaki Medical School
Hiromichi Metani– Associate Professor, Departmento of Rehabilitation Medicine, Kawasaki Medical School
Kazunari Furusawa– vice-president, Kibikogen Rehabilitation Center for Employment Injuries
Masaki Hyodo– director, Department of Rehabilitation Medicine, Taiyonomon Welfare Medical Center