Assessment of Brain Oxygen Drops During Surgery and Related Risk Factors for Cognitive Problems After Heart Surgery

Bursa Yuksek Ihtisas Training and Research Hospital

Status: Completed

Conditions: Cardiac Surgery; Cognitive Dysfunction; Cognitive Dysfunction, Postoperative

Study type: Observational

Funder types: Other

Identifiers

NCT07361068

011-KAEK-25 2023/02-15

Details and patient eligibility

About

This study examines whether decreases in brain oxygen levels during cardiac surgery are linked to postoperative cognitive dysfunction and identifies other factors that may increase the risk of cognitive impairment.

Full description

In this prospective study, the relationship between intraoperative cerebral oxygen saturation and postoperative cognitive dysfunction (POCD) was investigated in adult patients undergoing elective cardiac surgery with cardiopulmonary bypass (CPB). Patients with a preoperative Mini-Mental State Examination (MMSE) score ≥ 24, no history of cerebrovascular disease, and no conditions that could interfere with near-infrared spectroscopy (NIRS) monitoring were included.

Measurements were recorded at the following time points: T0 (before induction), T1 (15 minutes after induction), T2 (5 minutes after initiation of CPB), T3 (during the hypothermic phase of CPB), T4 (rewarming phase of CPB, at 34 °C), T5 (termination of CPB), and T6 (upon admission to the intensive care unit). Patients were divided into two groups according to postoperative cognitive outcomes: those who developed POCD and those who did not.

Cognitive function was assessed using the MMSE preoperatively and on postoperative days 4, 7, and 30. During surgery, cerebral oxygen saturation was measured at predefined time points using NIRS probes placed on the frontal region, and detailed intraoperative and perioperative data were recorded. Standardized interventions were implemented when a decrease of more than 20% in regional cerebral oxygen saturation (rSO₂) from baseline was detected in order to maintain adequate cerebral oxygenation.

Enrollment: 102 patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Planned elective CPB surgery
• Provision of written informed consent
• Absence of communication barriers that could interfere with preoperative and postoperative MMSE assessment
• No history of cerebrovascular disease
• Preoperative MMSE score ≥24
• Education level of at least high school
• Absence of any frontal deformity that could hinder NIRS monitoring

Exclusion criteria

• Preoperative use of antipsychotic or antidepressant medications
• Emergency cardiac surgery indication
• Presence of ≥50% carotid artery stenosis

Trial design

102 participants in 2 patient groups

Group POCD: Patients develop cognitive dysfunction after cardiac surgery

Description:

The POCD group (n=24) comprised patients undergoing elective cardiac surgery with cardiopulmonary bypass who developed postoperative cognitive dysfunction, defined as an MMSE score ≤23 at any postoperative assessment. ( Postoperative day 4 ,7, 30)

Group non-POCD : Patients did not develop postoperative cognitive dysfunction

Description:

The non-POCD group (n = 50) consisted of adult patients undergoing elective cardiac surgery with cardiopulmonary bypass whose MMSE scores remained ≥24 at all postoperative assessments, indicating no postoperative cognitive dysfunction.