In a pre-post study by Stiller et al. (1992), the effectiveness of IPPB on lung capacity was studied. The authors found that this style of mechanical ventilation significantly increased lung volume, as well as vital capacity (Stiller et al. 1992). More recently, a RCT by Laffont et al. (2008) found that IPPB had no short-term or long-term effects on pulmonary function, lung compliance or work of breathing in patients within 6 months of SCI who were not in respiratory failure. The authors reported that IPPB requires significant resources with respect to staff and equipment and is reported as unpleasant by many people with SCI.
While IPPB does not appear to be effective on lung function and compliance, further studies that explore the effect of IPPB on atelectasis, secretion management, and in acute respiratory failure following SCI are needed.
There is level 2 evidence (from one RCT: Laffont et al. 2008) that IPPB has no short-term or long-term effects on lung function within one year of SCI.
There is level 4 evidence (from one pre-post study: Stiller et al. 1992) that intermittent positive pressure breathing may increase lung volume as well as vital lung capacity in people with acute SCI.