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Published on: January 8, 2020
Afternoon Anesthesia Induction is Associated with Post-Induction Hypotension in Patients Undergoing Off-Pump Coronary
Huimin Wu1, Yuan Zhang1, Mu Jin1
1Department of Anesthesiology, Beijing Anzhen Hospital, Capital Medical University, Beijing, China.
Objectives:
Circadian rhythms are fundamental to cardiac homeostasis and cardiovascular function. Accordingly, we hypothesized that the timing of anesthesia induction could affect the incidence of postinduction hypotension (PIH) in patients undergoing cardiac surgery.
Design:
A retrospective, observational study was performed.
Setting:
This study was conducted in a university hospital.
Participants:
A total of 934 patients who underwent off-pump coronary artery bypass grafting (OPCAB) surgery between October 2024 and April 2025 were included.
Interventions:
None MEASUREMENTS AND MAIN RESULTS: We conducted a retrospective analysis of 934 patients who underwent OPCAB at our institution between October 2024 and April 2025. To address potential confounding, propensity score matching was employed to balance baseline characteristics between groups. In the propensity-matched cohort (360 pairs), PIH occurred in 55.28% of afternoon inductions versus 35.28% of morning inductions (p < 0.001). Afternoon induction was associated with higher odds of PIH (unadjusted odds ratio 2.08, 95% confidence interval 1.54-2.81; adjusted odds ratio 2.38, 95% confidence interval 1.65-3.43). A 5-variable nomogram achieved an area under the curve/C-index of 0.737 in the training set and 0.738 in the testing set.
Conclusions:
This study is the first to report an association that afternoon anesthesia induction is an independent risk factor for PIH in patients undergoing OPCAB. This provides crucial evidence for implementing time-based, individualized preoperative risk assessment and hemodynamic management in this high-risk population.
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