Use of air stacking and abdominal compression for cough assistance in people with complete tetraplegia

Study design: Cross-sectional. Objective: To assess cough using air stacking (AS) to assist inspiratory volume with abdominal compression (AC) during expiration in patients with American Spinal Injury Association Impairment Scale (AIS) A. Setting: Large tertiary hospital in Chile. Methods: Peak cough flow (PCF) was measured during four different interventions: spontaneous maximal expiratory effort (MEE); MEE while receiving AC (MEE-AC); MEE after AS with a manual resuscitation bag (AS-MEE); and MEE with AS and AC (AS-MEE-AC). Results: Fifteen in-patients with complete tetraplegia (C4-C6) were included. Median age was 33 years (16-56). PCF during the different interventions was PCF for MEE was 183 +/- 90 lmin(-1); PCF for MEE- AC was 273 +/- 119l min(-1); PCF for AS-MEE was 278 +/- 106 l min(-1) and PCF for AS-MEE-AC was 368 +/- 129 l min(-1). We observed significant differences in PCF while applying MEEAC and AS-MEE compared with MEE (P=0.0001). However, the difference in PCF value was greater using the AS-MEE-AC technique (P-0.00001). Conclusion: Patients with spinal cord injury (SCI) presented an ineffective cough that constitutes a risk factor for developing respiratory complications. The application of combined techniques (AS-MEE-AC) can reach near normal PCF values. This is a lowcost, simple and easily applied intervention that could be introduced to all patients with tetraplegia.