Volume Incentive Spirometry Reduces Pulmonary Complications in Patients After Open Abdominal Surgery: A Randomized Clinical Trial.

Objective: To compare the effect of diaphragmatic breathing and volume incentive spirometry (VIS) on hemodynamics, pulmonary function, and blood gas in patients following open abdominal surgery under general anesthesia.

Methods: A total of 58 patients who received open abdominal surgery were randomly assigned to the control group (n=29) undergoing diaphragmatic breathing exercises and the VIS group (n=29) undergoing VIS exercises. All the participants performed the six-minute walk test (6MWT) preoperatively to evaluate their functional capacity. Hemodynamic indexes, pulmonary function tests, and blood gas indexes were recorded before surgery and on the 1st, 3rd, and 5th postoperative day.

Results: The functional capacity was not significantly different between the two groups during the preoperative period (P >0.05). At 3 days and 5 days postoperatively, patients in the VIS group had a significantly higher SpO2 than that in the control group (P <0.05). Pulmonary function test values were reduced in both two groups postoperatively when compared to the preoperative values but improved for three and five days afterward (P <0.05). Of note, the significantly elevated levels of peak expiratory flow (PEF), forced expiratory volume in the first second (FEV1), forced vital capacity (FVC), and FEV1/FVC ratio were observed on the 1st, 3rd, and 5th postoperative days in the VIS group compared with those in the control group (P <0.05). Besides, bass excess (BE), and pH values were significantly higher in the VIS group on the 1st postoperative day than those in the control group (P <0.05).

Conclusion: Diaphragmatic breathing and VIS could improve postoperative pulmonary function, but VIS exercise might be a better option for improving hemodynamics, pulmonary function, and blood gas for patients after open abdominal surgery, hence lowering the incidence of postoperative pulmonary complications.