Eighteen trials (1,457 patients) were included.
On average, the quality of the studies was low and only 2 studies included groups of more than 50 participants; both of these were active control trials.
Respiratory physiotherapy intervention versus no intervention (4 studies).
All 4 trials assessed physical therapy, while two also assessed incentive spirometry. There was no evidence that there was any beneficial effect from these interventions when compared with the control.
Respiratory physiotherapy intervention versus another respiratory physiotherapy intervention (14 studies).
Atelectasis (14 studies) and pneumonia (9 trials, n=292): one trial conducted in children found a lower incidence of atelectasis with less intensive physical therapy than with more intensive physical therapy. No statistically significant differences were found within any other trials reporting on these outcomes.
Oxygenation (10 trials): only one study showed any statistically significant difference between the interventions. This study compared CPAP with physical therapy and showed an increase in oxygenation in the CPAP-treated group.
Pulmonary function (11 trials): only one study showed a significant difference between the interventions. CPAP and noninvasive ventilation both showed an increase in pulmonary function in comparison with incentive spirometry.
Adverse effects (7 studies): 2 studies reported no adverse effects. The adverse events reported in the other studies included gastric distension (2 to 10% of the participants), nausea (0 to 12%), inconvenience of the mask with CPAP (43%) and, with physical therapy treatment, percutaneous capillary oxygen saturation of less than 90% (4%) and tachycardia (1%).