Preoperative decline in skeletal muscle strength of patients with cardiovascular disease affects postoperative pulmonary complication occurrence: a single-center retrospective study

Background Dynapenia, defined as age-related skeletal muscle strength decline, has been reported as a poor prognostic factor in patients with cardiovascular disease. Decline in skeletal muscle strength (DS), the main symptom of dynapenia, may be an important clinical indicator in patients undergoing cardiac surgery. However, the relationship between DS and postoperative pulmonary complication occurrence is unclear. Herein, we investigated the relationship between preoperative DS and postoperative pulmonary complication occurrence in patients undergoing cardiac surgery. Methods We enrolled 125 patients who underwent cardiac surgery. DS was determined by low grip strength and quadriceps isometric strength. The patients were divided into DS and non-DS groups. The relationship between the clinical characteristics and preoperative physical function was compared, and factors associated with postoperative pulmonary complication occurrence were investigated using multivariate logistic regression analysis. Results There were 42 (33.6%) patients in the DS group and 83 (66.4%) patients in the non-DS group. Compared with the non-DS group, the DS group was significantly older and had a higher body mass index and Japan SCORE (operative mortality rate and major complication rate). The DS group also had a lower estimated glomerular filtration rate and preoperative Barthel index than the non-DS group. Furthermore the DS group had a significantly higher incidence of postoperative pulmonary complications and length of intensive care unit stay, and their postoperative rehabilitation was prolonged compared to the non-DS group. Multivariate logistic regression analysis revealed that DS was a determinant of postoperative pulmonary complications (odds ratio 4.26, 95% confidence interval 1.63‒11.14). Conclusions We showed that preoperative DS was an independent risk factor for postoperative pulmonary complications in patients undergoing cardiac surgery. Skeletal muscle strength before cardiac surgery may be an important clinical indicator for predicting the prognosis of patients from post-surgery to discharge and for planning postoperative rehabilitation programs.