Evaluation of Effectiveness of Preoperative Inspiratory Muscle Training to Prevent Post-Operative Pulmonary Complication in Patients Undergoing on Pump CABG Surgery

On Pump CABG patients are at higher risk of developing Post-Operative Pulmonary Complications (PPCs), leading to increased post-operative morbidity and mortality. Aim & Objective: To study the feasibility and effects of Preoperative Inspiratory Muscle Training (IMT) in patents who are at higher risk to develop PPCs and are planned for elective on pump CABG. Material and Method: After institutional ethics committee approval and obtaining written informed consent, 78 patients scheduled for elective on pump CABG were randomly divided into two groups. Group A (n=42) Intervention group and Group B (n=36) control group. The intervention group received 2 to 4 weeks of preoperative inspiratory muscle training apart from the usual care received by the patients in the control group. Primary outcome measures included patients satisfaction and motivation, compliance with therapy and to assess the Inspiratory Muscle Strength expressed as Pimax at residual volume. Secondary outcome variables were PPCs and length of hospital stay. Results: The feasibility of IMT was excellent with no adverse events. Inspiratory muscle strength increased by 36 % from 65.6 (15.8) cms of H20 at base line to 88.6 (29.1) cms of H20 at the end of the training period (p=0.001) compared to control group where the increase in inspiratory muscle strength was only 15 % from 67.8 (26.3) cms of H20 to 77.83 (27.3) cms of H20 (p=0.18). Lung functions like forced expiratory volume in 1 sec (FEV1), Inspiratory Vital Capacity (IVC) and FEV1/IVC remained unchanged during training period and before surgery in both groups. Length of hospital stay was 8.93 ( 1.94) days in the intervention group and 10.92 (5.78) days in the control group (p=0.24). Conclusion: IMT for 2 to 4 weeks in patients who are at high risk of developing PPCs undergoing on pump CABG are benefitted by preoperative IMT which is reflected by decreased incidence of PPCs.