Postoperative clinical care is prone to circadian desynchronization that, in turn, may influence health outcomes. We collected 1.8 million data points using 11 remote sensors during preoperative, in-hospital and post-discharge settings in 13 elective cardiac surgery patients. We found that room traffic continued during nighttime with ≥1 visit/h. Sound levels exceeded the recommended 45 dBA threshold (51.9±3.3 versus 48.3±4.2 dBA during nighttime). Brightness dropped at night (89.9±87.7 to 3.7±9.8 lux), but bright light exposures occurred. Ambient room temperature lacked sleep-inducing diurnal variability. Behavioral-physiological rhythms were disrupted (decreased amplitude of heart rate variability; unadjusted-p-value=0.03) and phase-shifted during hospitalization. Time awake during night hours increased from 10.7±7.9% preoperatively to 34.8±29.1% in-hospital (unadjusted p-value=0.0098). Cognitive function scores decreased (26.8±2.8 points preoperatively to 24.7±3.9 points in-hospital) with 31% of patients developing transient mild impairment. These data will inform the design of a controlled trial seeking to modify circadian/diurnal disruptors to enhance patient outcomes.