Cardiopulmonary response in spinal cord injury patients: effect of pneumatic compressive devices

The purpose of this study was to determine the effects of an inflatable abdominal corset and bilateral pneumatic leg splints on certain physiologic parameters during and after postural change in 27 quadriplegic patients. Data reflecting respiratory rate, tidal volume, heart rate, systolic and diastolic blood pressure were collected and analyzed. Measurements were acquired with patients in supine, 20 degrees head-up, 45 degrees head-up, and 20 degrees head-down positions. The study population was divided into 2 groups of cervical spinal cord injured patients: group I included 13 patients with C6 or C7 lesions; group II included 14 patients with C4 or C5 lesions. The mean time between injury and data collection was 47 days. Several trends were identified: (1) the neurologic level of lesion in quadriplegics appears relatively unimportant in determining cardiopulmonary response to postural change; (2) the use of assistive compressive devices does not improve pulmonary ventilatory parameters during postural change, although such devices do help maintain cardiovascular parameters; and (3) the abdominal corset appears more effective than pneumatic leg splints in maintaining blood pressure at pretilt levels. A tidal volume of 350ml to 400ml is most easily maintained by placing patients in a supine position and eschewing assistive compressive devices. Because the pneumatic devices proved successful in helping quadriplegic patients maintain cardiovascular stability during postural changes, therapeutic modalities, such as tilt table treatments, may be initiated at an earlier stage in the rehabilitation process.