Expiratory rib cage compression in mechanically ventilated adults: systematic review with meta-analysis

OBJECTIVE: To review the literature on the effects of expiratory rib cage compression on ventilatory mechanics, airway clearance, and oxygen and hemodynamic indices in mechanically ventilated adults. METHODS: Systematic review with meta-analysis of randomized clinical trials in the databases MEDLINE (via PubMed), EMBASE, Cochrane CENTRAL, PEDro, and LILACS. Studies on adult patients hospitalized in intensive care units and under mechanical ventilation that analyzed the effects of expiratory rib cage compression with respect to a control group (without expiratory rib cage compression) and evaluated the outcomes static and dynamic compliance, sputum volume, systolic blood pressure, diastolic blood pressure, mean arterial pressure, heart rate, peripheral oxygen saturation, and ratio of arterial oxygen partial pressure to fraction of inspired oxygen were included. Experimental studies with animals and those with incomplete data were excluded. RESULTS: The search strategy produced 5,816 studies, of which only three randomized crossover trials were included, totaling 93 patients. With respect to the outcome of heart rate, values were reduced in the expiratory rib cage compression group compared with the control group [-2.81 bpm (95% confidence interval [95%CI]: -4.73 to 0.89; I(2): 0%)]. Regarding dynamic compliance, there was no significant difference between groups [-0.58mL/cmH(2)O (95%CI: -2.98 to 1.82; I(2): 1%)]. Regarding the variables systolic blood pressure and diastolic blood pressure, significant differences were found after descriptive evaluation. However, there was no difference between groups regarding the variables secretion volume, static compliance, ratio of arterial oxygen partial pressure to fraction of inspired oxygen, and peripheral oxygen saturation. CONCLUSION: There is a lack of evidence to support the use of expiratory rib cage compression in routine care, given that the literature on this topic offers low methodological quality and is inconclusive.