Benefits from Implementing Low- to High-Intensity Inspiratory Muscle Training in Patients Undergoing Cardiac Surgery: A Systematic Review.

Cardiac surgery procedures are among the main treatments for people with cardiovascular disease, with physiotherapy playing a vital part. Respiratory complications are common and associated with prolonged Intensive Care Unit (ICU) and hospital stay, as well as increased mortality. Inspiratory muscle training has been found to be beneficial in improving respiratory muscle function in critically ill patients and patients with heart failure. The purpose of this review is to present the results of implementing inspiratory muscle training (IMT) programs in patients before and/or after cardiac surgery. The PubMed, Embase and Science Direct databases were searched from January 2012 to August 2023. In the present review, randomized controlled clinical trials (RCTs), clinical trials and quasi-experimental studies conducted in adult patients pre and/or post cardiac surgery were included. Fifteen studies were considered eligible for inclusion in the review. The results revealed that the IMT programs varied in intensity, repetitions, and duration in all included studies. Most studies implemented the IMT after the surgery. Statistical significance between groups was noted in Maximal Inspiratory Pressure and the 6-Minute Walk Distance Test. Preoperative and postoperative programs could improve inspiratory muscle strength, pulmonary function, and functional capacity as well as decrease the length of hospital stay in patients undergoing cardiac surgery. No clear evidence emerged favoring low or higher IMT intensities. The combination of IMT with other forms of exercise might be beneficial in patients undergoing cardiac surgery. However, further RCTs are required to provide confirming evidence.