The beneficial effects of physical preoperative and postoperative training for the cognitive function in cardiosurgical patients

Abstract Background and aim The cardiac surgery patients have an increased risk of postoperative cognitive dysfunction (POCD). The positive healing effects of physical exercise was demonstrated early in patients with cognitive impairment. The aim of the study was to evaluate the effect of physical preoperative and postoperative training for the cognitive function in patients undergoing on-pump coronary artery bypass grafting (CABG). Methods We analyzed the neurophysiological data from 125 male coronary artery disease (CAD) patients who participated in two sub-studies: the patients with a short preoperative course of treadmill training (n=33) and with postoperative aerobic exercise training (n=92). The study of preoperative physical training included CABG-candidates, which were divided into 2 groups: with (n=17) and without training (n=16). The preoperative physical training consisted of a 5–7 day course of intensive training on a treadmill. The study with postoperative aerobic exercise training enrolled CAD patients, undergoing on-pump CABG, which were divided into 2 groups: with supervised cycling training (n=39) and without training (n=53). Three-week trainings course began on the 14-th day after CABG. The patients with and without preoperative and postoperative physical training were comparable in terms of preoperative characteristics and intraoperative parameters. The patients were underwent the neuropsychological and EEG examination to assess postoperative changes in neurophysiological performance. Results The patients with preoperative treadmill training had the POCD incidence at 7–10 days after GABG in 44% cases vs. 74% - in the group without training. The relative risk of POCD developing in the patients with preoperative training was: OR=0.24, 95% CI: 0.07–0.81, Z=2.297, p=0.02. Additionally, the patients with preoperative training demonstrated a lower power in the theta (4–6 Hz) and beta1 (13–20 Hz) frequency ranges 7–10 days after CABG. The patients with postoperative cycling training also demonstrated better cognitive function at 1 month after CABG compared to the patients without training. The incidence of POCD was 21% in the cycling training group vs. 44% – in the group without training. The relative risk of POCD developing was: OR=0.23, 95% CI: 0.09–0.60, Z=3.041, p=0.0024. Also, it was found that the postoperative cycling training group showed a lower percentage theta power increase at 1 month after CABG. Conclusion Both the short preoperative and three-week postoperative physical training course can produce beneficial effects on the postoperative neurophysiological status in CABG patients. The engagement of physical training in the rehabilitation program of CABG patients can improve cognitive functioning after cardiac surgery. Funding Acknowledgement Type of funding source: Foundation. Main funding source(s): RFBR and Kemerovskaya region