Cognitive Functions on Coronary Surgery

Study Overview
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Brief Summary
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The aim of this study is to examine the effects of different but safe levels of arterial oxygen levels used in cardiac surgeries on cerebral oxygenation during the operation. It is also to investigate the effect on cognitive functions in the postoperative period. For our study the investigators will conduct a randomized control trial. Patients will be randomly assigned to one of two possible study groups according to the arterial oxygen levels.If there is any abnormality in cerebral oxygen levels during surgery, necessary intervention will be made by doctors.

Detailed Description
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In most cardiovascular surgeries, patients are frequently followed up at hyperoxemic level for safety purposes against the risk of tissue hypoxia that may develop during surgery due to CPB use. At the level of hyperoxemia, there are opinions that the ischemia-reperfusion damage increases with the follow-up of CABG surgery, microcirculation is impaired and tissue oxygenation is impaired due to the resulting hyperoxemic vasoconstriction. Recent research has focused on evaluating optimal oxygen levels in CPB during cardiac surgery. However, the potential of tightly regulated intraoperative normoxia to improve POCD following cardiac surgery has not been studied prospectively. The purpose of this study is to determine whether patients who underwent CPB and CABG, which were preserved under normoxic conditions during the intraoperative period, would have a lower incidence of early and late POCD than those exposed to hyperoxia.

Official Title
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The Effect of Intraoperative Arterial Oxygen Levels on Cognitive Functions After Coronary Bypass Graft Surgery

Conditions
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Neurocognitive Disorders

Intervention / Treatment
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* Procedure: procedure: cerebral oxygenation intervention


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: adult patients scheduled to undergo elective cardiopulmonary bypass graft surgery Exclusion Criteria: severe preoperative cognitive impairment(i.e. dementia, intellectual disorder) Non-Turkish speaking patients presence of end-stage organ failure patients requiring emergency coronary surgery surgical procedures requiring single lung ventilation

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 90 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: normoxy<br>Group 1(n=50) FiO2%40, PaO2<180 ve PaO2≥80mmHg MMSE will be applied to patients before surgery. At the determined measurement times body and blood temperature, SpO2, HR, MAP, PH, blood gas lactate, blood gas base deficit, urine output, PaO2, PaCO2, Htc, FiO2, right and left rSO2 values were monitored. An rSO2 less than 45% triggered an alarm, the anesthesiologist timed the event, and after 60 seconds initiated an intervention protocol means; PaO2 levels were checked, PaO2> 100 mmHg was achieved, if not improved, pump blood flow, mean arterial pressure were increased, if there is still no response and hematocrit <20%, patients were scheduled for erythrocyte transfusion until the rSO2 was restored to at least 60% at both probes.In the postoperative period, at the 24th hour, when routine cardiological controls were performed 1., 3., 6. Simultaneous MMSE will be repeated in months. | Procedure: procedure: cerebral oxygenation intervention<br>* During the surgery, cerebral oxygenation will be followed and intervention will be made to pH, PaO2, PaCO2, mean arterial pressure, hematocrit when necessary. In addition perfusion flow was maintained at or close to between 2.2-2.5 L/min/m2 . Perfusion pressure was adjusted using a phenylephrine infusion to maintain a mean arterial pressure of 50 to 70 mm Hg.<br>|
| Experimental: hyperoxia<br>Group 2(n=50) FiO2%100, PaO2≥180mmHg MMSE will be applied to patients before surgery. At the determined measurement times body and blood temperature, SpO2, HR, MAP, PH, blood gas lactate, blood gas base deficit, urine output, PaO2, PaCO2, Htc, FiO2, right and left rSO2 values were monitored..In the postoperative period, at the 24th hour, when routine cardiological controls were performed 1., 3., 6. Simultaneous MMSE will be repeated in months. | Procedure: procedure: cerebral oxygenation intervention<br>* During the surgery, cerebral oxygenation will be followed and intervention will be made to pH, PaO2, PaCO2, mean arterial pressure, hematocrit when necessary. In addition perfusion flow was maintained at or close to between 2.2-2.5 L/min/m2 . Perfusion pressure was adjusted using a phenylephrine infusion to maintain a mean arterial pressure of 50 to 70 mm Hg.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| postoperative neurocognitive function | Change on MMSE is important for neurocognitive disorder.The MMSE consists of cognitive functions of orientation, attention, calculation, memory and language. | 12 hours after surgery | 
| postoperative neurocognitive function | Change on MMSE is important for neurocognitive disorder.The MMSE consists of cognitive functions of orientation, attention, calculation, memory and language. | 24 hours after surgery | 
| postoperative neurocognitive function | Change on MMSE is important for neurocognitive disorder.The MMSE consists of cognitive functions of orientation, attention, calculation, memory and language. | 1 month after surgery | 
| postoperative neurocognitive function | Change on MMSE is important for neurocognitive disorder.The MMSE consists of cognitive functions of orientation, attention, calculation, memory and language. | 3 months after surgery | 
| postoperative neurocognitive function | Change on MMSE is important for neurocognitive disorder.The MMSE consists of cognitive functions of orientation, attention, calculation, memory and language. | 6 months after surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Extubation time after surgery | Weaning times from mechanical ventilation among patients who are followed up with the same intensive care approach after surgery | During the hospitalization for postoperative recovery ,average 8 days | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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cardiovascular surgery, cerebral oxymetre, neurocognitive assessment