Perioperative respiratory muscle exercise in patients undergoing cardiac surgery: An evidence-based review

Background: Enhanced respiratory muscle management is imperative in cardiac surgery patients due to their universal risk of decreased perioperative respiratory muscle strength. Objectives: Most existing articles primarily examine respiratory muscle exercise during either the preoperative, postoperative, or at-home phases. Consequently, there is a crucial need to consolidate the evidence for respiratory muscle exercise throughout the perioperative period of cardiac surgery. Methods: A literature search was performed, encompassing guideline networks and databases up until July 2023. The literature was classified into seven thematic categories: preoperative assessment, patient education, trainers, training plans, quality control, safety monitoring, and outcome assessment. The quality of the included literature was assessed using the GRAGE evidence grading system to ascertain the level of recommendation associated with each piece of evidence. Results: Nineteen papers were reviewed, encompassing 24 suggestions. These consisted of two suggestions on preoperative assessment, four on patient education, two on trainers, six on training programs, seven on quality control, two on safety monitoring, and one on outcome assessment. All 24 suggestions were categorized as strong recommendations, with 14 classified as high-quality evidence and ten as moderate-quality evidence. Conclusions: Our study presents a succinct synthesis of the most robust evidence available on perioperative respiratory muscle exercise in cardiac surgery patients. We identified ten high-quality suggestions while an additional 14 moderate-quality suggestions. In the context of perioperative exercise, we recommend that moderate-intensity inspiratory muscle exercises be provided during the preoperative and postoperative phases upon transfer to the ward. We advocate for the implementation of low-intensity inspiratory muscle exercises during the postoperative phase while patients are in the intensive care unit.