Cerebral Oxygen Saturation Monitoring In Cardiac Surgery (COSMICS)

Instituto Nacional de Cardiologia de Laranjeiras

Status: Completed

Conditions: Cardiac Disease; Cognitive Dysfunction

Treatments: Device: Cerebral oximetry monitor (The INVOS® Cerebral/Somatic Oximeter) and protocol-based interventions

Study type: Interventional

Funder types: Other

Identifiers

NCT04766554

COSMICS STUDY

Details and patient eligibility

About

Neurological dysfunction continues to be one of the complications of considerable concern in patients undergoing cardiac surgery. It was previously reported in the literature, that cerebral oxygen desaturation during cardiac surgery was associated with an increased incidence of cognitive impairment. This study aims to determine whether continuous monitoring of cerebral oximetry improves the neurocognitive outcome in coronary artery bypass surgery when associated with predetermined intervention protocol to optimize cerebral oxygenation.

Full description

Despite all the progress over the last decades regarding the improvement of the perioperative care of patients with heart disease and the development of new surgical techniques, neurological dysfunction continues to be one of the complications of the greatest concern in patients undergoing cardiac surgery with cardiopulmonary bypass. Brain injury can manifest itself through permanent or temporary injury, contributing to the increase in-hospital mortality, in the length of stay in intensive care, in the length of hospital stay, to a higher incidence of motor dysfunction requiring rehabilitation, and consequently, to reduced quality of life.

Even though the causes of brain injury are multifactorial, perioperative cerebral hypoperfusion, tissue hypoxia, and thromboembolic events are among the main factors related to neurological dysfunction.

Several clinical studies have indicated an association between cerebral desaturation and the increase of neurological complications. Cerebral oximetry monitoring using near-infrared spectroscopy (NIRS) is a non-invasive technique used to estimate regional cerebral oxygen saturation (rSO2) and has been associated with diminishing the incidence of neurological complications.

There is no consensus in the literature about its real benefit, mainly due to the absence of well-designed scientific studies that demonstrate that cerebral desaturation associated with intervention measures to improve rSO2, are related to the prevention of neurological dysfunction in adult cardiac surgery.

The study hypothesis evaluates whether continuous monitoring of cerebral oximetry improves the neurocognitive outcome in coronary artery bypass surgery when associated with early interventions to optimize rSO2.

Enrollment: 326 patients

Sex: All

Ages: 60+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Age 60 or older
• Elective coronary artery bypass graft surgery using cardiopulmonary bypass
• Preoperative cognitive assessment by means of Mini-Mental State Examination (MMSE) test, greater than or equal to 24
• Signed informed consent

Exclusion criteria

• Patients with focal neurologic deficit
• Carotid artery stenosis greater than 70%
• Patients with pre-existing cognitive dysfunction
• Patients with psychotic disorders
• History of allergy to adhesive part of the electrode
• History of craniofacial surgery

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Triple Blind

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326 participants in 2 patient groups

Cerebral Oxymetry Monitoring

Active Comparator group

Description:

The following procedures should be performed sequentially in the event of cerebral desaturation after 30 seconds: 1. The positioning of the head, the presence of facial plethora, and bad position of catheters should be corrected; 2. In case of arterial hypotension, the causal factors should be assessed and treated; 3. In the presence of arterial hypoxemia, the causal factors should be assessed and treated to maintain a PaO2 \> 150 mmHg; 4. In the presence of hypercapnia, adjust the ventilation parameters avoiding hyperventilation; 5. In the presence of anemia, the causal factors should be assessed, and the decision to undergo transfusion should also take into consideration the presence of tissue hypoperfusion; 6. In cases of SvO2 below 70% and signs of hemodynamic instability, optimize fluid replacement and ventricular global contractility; 7. Assess the increase of brain consumption of O2, avoiding the superficial level of anesthesia, hyperthermia, and tremors.

Treatment:

Device: Cerebral oximetry monitor (The INVOS® Cerebral/Somatic Oximeter) and protocol-based interventions

Control Group

No Intervention group

Description:

Patients will be treated according to the attending anesthesiologist, without the monitoring of cerebral oximetry, but to maintain a heart rate between 70 - 100 bpm, lactate levels \<3 mmol/L and urine output\> 0.5mL/Kg/h. In case of arterial hypotension the causal factors should be assessed and treated; in case of SvO2 below 70% and signs of hemodynamic instability, optimize volume replacement and global ventricular contractility through inotropic agents (epinephrine, dobutamine or milrinone); in the presence of anemia (Hb \<6 to 7g/dL during CPB or Hb \<8g/dL in the pre-CPB or post-CPB period), the causal factors should be assessed and the decision to transfuse should also take into account the presence of hypoperfusion tissue (increased lactate, low SvO2, acidosis); in episodes of bradycardia with hemodynamic instability, atropine may be used.