A study on the effect of manual hyperinflation on oxygenation and hemodynamic parameters in mechanically ventilated patients after valve replacement surgery

Abstract

BACKGROUND: Valve replacement surgeries being a major surgery require general anesthesia. Patients are kept on mechanical ventilation postoperatively which can cause some major dysfunctions of the respiratory and circulatory systems of the human body. Manual hyperinflation (MHI) is a technique that provides a tidal volume greater than the baseline volume and produces a turbulent flow that brings benefits such as improvement of static compliance of the respiratory system, increased oxygenation, mobilization of secretions, and recruitment of collapsed areas of the lung. OBJECTIVES: The aim of this study was to compare the effectiveness of MHI in valve replacement patients on mechanical ventilation in terms of SpO2, heart rate (HR), respiratory rate (RR), blood pressure (BP), mean arterial pressure (MAP), and rate pressure product (RPP). MATERIALS AND METHODS: Thirty cardiothoracic intensive care unit patients who were intubated and mechanically ventilated after valve replacement surgery were given 3–4 MHI breaths with an O2 flow rate of 15 L/min for 6–8 sets or till secretions were heard. Means of the pretreatment and posttreatment values were calculated and compared by the paired t-test. Results: The results from the statistical analysis show that SpO2 remained almost same (P = 0.499). However, heart rate increased significantly (P = 0.048) after MHI. There was no adverse change in RPP (P = 0.409), but BP (P = 0.00 and 0.006), RR (P = 0.000), and MAP decreased significantly (P = 0.0005). CONCLUSION: The MHI technique seems to promote more improvement in hemodynamic parameters than in oxygenation.