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Heart rate response during sleep in elderly patients after fast-track hip and knee arthroplasty

Variability in heart rate response (HRR) can be used as a measure for autonomic nervous system function, which may influence sleep disturbances and the recovery phase after major surgery. The aim of this study was to evaluate autonomic function by assessment of HRR during sleep arousals in the postoperative period after fast-track hip and knee arthroplasty. Determination of autonomic function was gained from polysomnographic evaluation of 10 patients > 60 years undergoing either hip or knee arthroplasty (mean age 69.9 years) evaluating HRR during the different sleep phases. Sleep monitoring took place in the patients’ home preoperatively, during hospitalization on the first postoperative night, and on the fourth postoperative night at home. HRR was reduced (P < 0.01) during arousal from non-REM stage 2 sleep on the first postoperative night, and was still reduced on the fourth postoperative night compared to preoperative level (P = 0.01). HRR during arousal from REM sleep was not different between the preoperative and fourth postoperative night (P = 0.92), while this could not be determined on the first postoperative night where REM sleep disappeared. The reduced HRR during sleep arousal after major arthroplasty surgery in elderly patients may reflect a functional change in sympathetic nervous system potentially relevant for postoperative sleep changes, fatigue and cognitive function.