Effects of Manual Lung Hyperinflation Using Rebreathing Bags on Cardiorespiratory Parameters in Intubated Adults

Manual hyperinflation is a technique that is commonly used by physiotherapists to provide a greater than baseline tidal volume to the lungs of mechanically ventilated patients. The use of this technique is based more on clinical experience than on scientific evidence as the physiological effects of manual hyperinflation are uncertain. This review uses evidence-based principles to investigate the effects of manual hyperinflation using rebreathing bags on lung compliance, oxygenation and haemodynamic variables in intubated adults. The lack of good quality randomised controlled trials makes it difficult to draw firm conclusions and so the strategic implications and recommendations for further research are discussed. There is also consideration of how best to traverse the ‘grey zones’ of clinical practice where evidence is inadequate or contradictory. Physical Therapy Reviews 2003; 8: 135–141 Abbreviations: CI, confidence interval; CL, lung compliance; FiO2, fraction of inspired oxygen; MAP, mean arterial pressure; MHI, manual hyperinflation; PaO 2 , partial pressure of oxygen; PEEP, positive end expiratory pressure; SaO 2 , saturation of oxygen in