Effect of Lung Manual Hyperinflation (MHI) on Oxygenation of Patients Following Abdominal Surgery and T-Tube Support

Abstract

Background: Postoperative pulmonary complications (PPC) are of the major reasons for death. Prolonged mechanical ventilation (PMV) and delayed extubation are leading to the incidence of more seriously complications. The effect of hyperinflation has not been investigated in control of these complications in patients who have been weaned from mechanical ventilation and are undergoing T-tube support. Aim: Investigation of MHI effect on oxygenation of patients following abdominal surgery and T-tube support. Method: This clinical trial was performed on 40 patients undergoing abdominal surgery and T-tube support hospitalized in intensive care units of hospitals in Mashhad, Iran, in 2015-2016. The participants were divided randomly into two experimental and control groups. In the experimental group, MHI technique was performed using Mapleson circuit for three twenty-minute periods. The control group received routine hospital care. The two groups were compared for PaO2, PaCO2 and SpO2 before intervention, 5 and 20 minutes after intervention. Data were analyzed using SPSS software. Results: The mean age was 66.7±8.3 and 67.5±9.0 years in experimental and control groups, respectively. In intergroup comparison using independent t-test, the mean PaCO2, PaO2 and SpO2 had no significant differences in the experimental group before the intervention. However, the means SpO2 and PaO2 at 5 and 20 minutes after intervention were significantly higher in the experimental group (p<0.001) than the control group. The mean PaCO2 at 5 and 20 minutes after intervention decreased significantly in the experimental group (p=0.03). Implications for Practice: The results showed that the MHI technique by increasing oxygenation and ventilation could improve lung function in the participants, resulting in shortening the duration of mechanical ventilation, accelerating the process of extubation, and thus faster patient recovery.