PCO₂ Gap and Lactate as Predictors of POCD After Cardiac Surgery

N/ANot Yet RecruitingNCT07843186

Ain Shams University185 enrolled

Overview

This prospective observational study aims to evaluate whether intraoperative venous-to-arterial carbon dioxide partial pressure difference (PCO₂ gap) and arterial lactate levels can serve as early predictors of postoperative cognitive dysfunction (POCD) in elderly patients undergoing elective cardiac surgery with cardiopulmonary bypass. Intraoperative measurements of PCO₂ gap and lactate will be correlated with perioperative cognitive outcomes assessed using the Montreal Cognitive Assessment (MoCA) and postoperative delirium screening using the Confusion Assessment Method for the ICU (CAM-ICU).

This prospective observational cohort study will be conducted at El-Demerdash Hospital, Ain Shams University. Patients aged 65 years and older undergoing elective cardiac surgery with cardiopulmonary bypass will be enrolled. Serial measurements of the PCO₂ gap and arterial lactate will be obtained before induction, during CPB, at the end of CPB, 30 minutes after weaning from CPB, and immediately postoperatively. Cognitive function will be evaluated preoperatively and one month after surgery using the Montreal Cognitive Assessment (MoCA). Postoperative delirium will be assessed daily during ICU stay using CAM-ICU. The study will investigate the predictive value of intraoperative PCO₂ gap and lactate levels for postoperative cognitive dysfunction and determine potential cutoff values associated with cognitive decline.

Study Type

OBSERVATIONAL

Enrollment

185

Conditions

Postoperative Cognitive Dysfunction (POCD)Cardiac Surgery Cardiopulmonary Bypass

Outcomes

Primary Outcomes

Predictive Value of Intraoperative PCO₂ Gap and Arterial Lactate Levels for Postoperative Cognitive Dysfunction (POCD

To evaluate whether intraoperative venous-to-arterial carbon dioxide partial pressure difference (PCO₂ gap) and arterial lactate levels predict postoperative cognitive dysfunction in elderly patients undergoing elective cardiac surgery with cardiopulmonary bypass. POCD will be assessed by changes in Montreal Cognitive Assessment (MoCA) scores from the preoperative baseline to 1 month postoperatively.

Time frame: Baseline (preoperative) and 1 month postoperatively

Secondary Outcomes

Early Postoperative Delirium Assessed by the Confusion Assessment Method for the ICU (CAM-ICU)

To determine the occurrence of early postoperative delirium using the Confusion Assessment Method for the ICU (CAM-ICU). CAM-ICU is a dichotomous assessment (positive or negative), where a positive result indicates the presence of delirium

Time frame: Daily during the first 5 postoperative days or until ICU discharge, whichever occurs first

Determination of Cutoff Values for Intraoperative PCO₂ Gap and Arterial Lactate Levels Predictive of POCD

To identify optimal cutoff values for intraoperative PCO₂ gap and arterial lactate levels associated with postoperative cognitive dysfunction in elderly patients undergoing cardiac surgery with cardiopulmonary bypass.The PCO₂ gap will be measured in mmHg, and arterial lactate concentration will be measured in mmol/L.

Time frame: 1 month postoperative

Correlation of (CAM - ICU) to MoCA for prediction of cognitive impairmentat 5 days post operative

To evaluate the correlation between postoperative delirium assessed by the Confusion Assessment Method for the ICU (CAM-ICU) and postoperative cognitive function assessed by the Montreal Cognitive Assessment (MoCA).CAM-ICU will be recorded as a dichotomous result (positive or negative), with a positive result indicating the presence of delirium. MoCA will be recorded as a total score ranging from 0 to 30, with higher scores indicating better cognitive function

Time frame: CAM-ICU: Daily during the first 5 postoperative days; MoCA: baseline preoperatively and 1 month postoperatively

Incidence of POCD at 1 month postoperatively, defined by a decline in MoCA scores from baseline in elderly cardiac patient.

To determine the incidence of postoperative cognitive dysfunction, defined as a decline in MoCA score from the preoperative baseline, one month after cardiac surgery

Time frame: Baseline (preoperative) and 1 month postoperatively

Duration of Mechanical Ventilation in Relation to Intraoperative PCO₂ Gap and Arterial Lactate Levels

To evaluate the association between intraoperative PCO₂ gap and arterial lactate levels and the duration of mechanical ventilation following cardiac surgery with cardiopulmonary bypass. Duration of mechanical ventilation will be measured in hours from the end of surgery until successful extubation, as documented in the patient's medical and ventilator records.

Time frame: Measured from the end of surgery until successful extubation (up to 30 days)

Duration of Intensive Care Unit Stay in Relation to Intraoperative PCO₂ Gap and Arterial Lactate Levels

To evaluate the association between intraoperative PCO₂ gap and arterial lactate levels and the duration of intensive care unit (ICU) stay following cardiac surgery with cardiopulmonary bypass. ICU stay will be measured in days from ICU admission after surgery until ICU discharge, as documented in the patient's medical records.

Time frame: From ICU admission after surgery until ICU discharge, up to 30 days

Duration of Hospital Stay in Relation to Intraoperative PCO₂ Gap and Arterial Lactate Levels

To evaluate the association between intraoperative PCO₂ gap and arterial lactate levels and the duration of hospital stay following cardiac surgery with cardiopulmonary bypass. Hospital stay will be measured in days from the end of surgery until hospital discharge, as documented in the patient's medical records.

Time frame: From the end of surgery until hospital discharge, up to 30 days