Objective: This study retrospectively investigated the effects of different doses of dexmedetomidine combined with propofol on postoperative delirium in older adults undergoing cardiac surgery.
Methods: The medical records of 82 older adults undergoing cardiac surgery admitted to two hospitals between August 2019 and August 2022 were analyzed. The participants were divided into two groups based on the dexmedetomidine dose: group A (0.5 µg/kg dexmedetomidine + propofol) and group B (1.0 µg/kg dexmedetomidine + propofol). The mean arterial pressure (MAP), heart rate (HR), anesthesia depth index (NTI), and incidence of postoperative delirium (POD) at 7 days after surgery were compared.
Results: MAP and HR were significantly higher in group A than in group B during extubation and 10 minutes after extubation and significantly higher than the values before anesthesia induction. At all time points post-anesthesia induction, NTI was higher in group B than in group A, and the incidence of POD within 7 days after surgery was significantly higher in group A. The Prince-Henry pain scores were higher in group A than in group B at 1, 4, 24, and 48 hours after surgery.
Conclusions: Higher dexmedetomidine doses were associated with more stable hemodynamics and stronger effects on POD in older adults undergoing cardiac surgery.
Keywords: Cardiac surgery; dexmedetomidine; hemodynamics; older adult; postoperative delirium; propofol.