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Published on: August 17, 2022
Cerebral oxygenation impairment and S-100β protein release during off-pump coronary artery revascularization
Georgia G Tsaousi1, Antonis A Pitsis, Despina V Deliaslani
1Department of Anesthesiology and Intensive Care, AHEPA University Hospital, Thessaloniki, Greece. tsaousig@otenet.gr
Insights
Off-pump coronary artery bypass grafting (OPCAB) temporarily impacts cerebral oxygenation and S-100β protein levels. These changes are transient, remain near normal, and largely reverse within six hours post-surgery.
Area of Science:
- Cardiovascular Surgery
- Neuroanesthesia
- Cerebral Physiology
Background:
- Off-pump coronary artery bypass grafting (OPCAB) is a complex procedure.
- Monitoring cerebral oxygenation during OPCAB is crucial for patient outcomes.
- S-100β protein is a potential biomarker for brain injury.
Purpose of the Study:
- To assess cerebral oxygenation impairment during OPCAB.
- To evaluate S-100β protein as a marker of cerebral changes during OPCAB.
- To determine the reversibility of these changes post-surgery.
Main Methods:
- Prospective cohort study involving 35 patients undergoing OPCAB.
- Cerebral oxygenation indices and S-100β protein levels were measured at multiple time points.
- Measurements included arterial and jugular bulb blood samples, hemodynamic data, and S-100β protein levels up to 24 hours postoperatively.
Main Results:
- Hemodynamic deterioration occurred during heart positioning, impacting cerebral oxygenation indices.
- Despite transient adverse effects, cerebral oxygenation indices remained within normal limits.
- S-100β protein levels increased, peaking by surgery's end and decreasing by postoperative day one.
Conclusions:
- OPCAB surgery causes transient derangements in cerebral oxygen indices and S-100β release.
- These changes are generally within the near-normal range.
- Cerebral oxygenation and S-100β levels largely normalize within six hours post-OPCAB.
Objective:
To elucidate the magnitude of global cerebral oxygenation impairment, using cerebral oxygenation indices and S-100β protein as potential markers, during off-pump coronary artery bypass grafting (OPCAB).
Design:
Prospective cohort study.
Setting:
Tertiary cardiac center.
Participants:
Thirty-five patients undergoing OPCAB.
Interventions:
Jugular bulb and arterial blood samples for cerebral oxygenation indices (arterial oxygen and carbon dioxide partial pressures, jugular bulb oxygen saturation, arterial-jugular bulb oxygen content, arterial-jugular carbon dioxide partial pressure, brain oxygen extraction ratio, and estimated respiratory quotient) and S-100β protein determination were collected at anesthesia induction; anterior, inferior, and posterior wall anastomoses; after sternal closure; and 6 hours postoperatively. Concomitant hemodynamic data were obtained. The S-100β determination was extended to 12 and 24 hours postoperatively.
Measurements And Main Results:
Heart positioning for the target vessel exposure induced significant hemodynamic deterioration (p < 0.001). Although cerebral oxygenation indices were influenced adversely by a low-cardiac-output state mainly during vertical heart dislocation (p < 0.001), they remained within normal limits. Hemodynamic and cerebral oxygenation statuses reverted to baseline within 6 hours postoperatively. Similarly, S-100β jugular bulb and arterial protein levels presented a gradual increase, which peaked by the end of surgery (means, 0.54 and 0.62 μg/L, respectively; p < 0.001) and then decreased by the first postoperative day. Jugular bulb-arterial S-100β levels were maximized during posterior wall anastomosis (0.098 μg/L; p < 0.01).
Conclusion:
Although exposure of the 3 main coronary arteries during OPCAB promotes derangement of the cerebral oxygen indices and S-100β release, this seems to be transient, remains within the near-normal range, and is reversible almost completely 6 hours postoperatively.
