Comparison of head-down tilt versus flat position on mucus clearance and respiratory mechanics in mechanically ventilated patients: A randomized crossover trial

Background: Most of the mechanically ventilated patients in the intensive care unit have impaired bronchial mucociliary transport and copious sputum production due to abnormal cilia function. This leads to pulmonary complications such as lung collapse, pulmonary infection, and hypoxemia. Objective: This study was designed to compare the effects of a head-down tilt position and a flat position in improving mucus clearance and respiratory mechanics in mechanically ventilated patients. Materials and Methods: This was a randomized crossover study in which 24 patients with 17 males and 7 females were randomly allocated to one of two treatment sequences over 2 days. The sequence involved head-down tilt position followed by 4 hours later, a flat position, and the order was reversed on the second day. Chest physiotherapy techniques were given in each position on both consecutive days. In the second sequence, a supine position preceded the head-down tilt position. Measurement of sputum was taken postintervention in each place on day one and day two. Analyses of respiratory mechanics (static compliance, dynamic compliance, and resistance) were made at baseline, immediately postintervention, and 30 minutes postintervention. A paired ttest was used to compute the differences in sputum volume. Two way repeated measures analysis of variance (ANOVA) was used to calculate the differences in respiratory mechanics. Statistical significance was set at p < 0.05. Results: A head-down tilt position produced more sputum than a flat position immediately after chest physiotherapy techniques (p < 0.05). Static and dynamic compliance improved immediately following chest physiotherapy techniques (p < 0.05). Conclusion: A head-down tilt position can be recommended over the a flat position in improving mucus clearance and respiratory mechanics in mechanically ventilated patients.