Cardiac Disease, Cognitive Dysfunction
Conditions
Keywords
Intraoperative Neurophysiologic Monitorings
Brief summary
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.
Detailed 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.
Interventions
DEVICECerebral oximetry monitor (The INVOS® Cerebral/Somatic Oximeter) and protocol-based interventions
In the intervention group, an alarm threshold below 15% of the baseline rSO2 value will be established. Based on the predetermined algorithm the rSO2 will be maintained at or above 85% of the baseline measurements. If the rSO2 reaches levels below 15% of the baseline values or below 50% in absolute value for over 30 seconds, protocol-based interventions will be performed to restore rSO2 to baseline levels.
Sponsors
Instituto Nacional de Cardiologia de Laranjeiras
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
TRIPLE (Subject, Investigator, Outcomes Assessor)
Masking description
Patients will be masked concerning the allocation group. The anesthesiologist responsible for conducting the case will not be involved in the application of the neurocognitive tests, nor will he be aware of the test results. Investigators who apply the tests will be covered up by the patient allocation group.
Intervention model description
Patients will be monitored with cerebral oximetry using INVOS 5100 monitor (Covidien, Boulder, CO), with electrodes applied bilaterally in the frontal region. Following the placement of the electrodes, the baseline records HR, blood pressure, rSO2, and peripheral O2 saturation (SPO2) will be recorded following 1 minute of electrode placement and the proper verification of the signal on the monitor. Later, during the surgery, if the rSO2 reaches levels below 15% of the baseline values or below 50% in absolute value for over 30 seconds, protocol-based interventions will be performed in the intervention group to return the oximeter to baseline values. The alarm on the equipment should be programmed to signal values below 15% of the baseline values.
Eligibility
Sex/Gender
ALL
Age
60 Years to No maximum
Healthy volunteers
No
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
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Preoperative cognitive function | Pre-surgery (within 10 days before) | Mini Mental State Examination (MMSE) |
| Postoperative cognitive dysfunction - delayed cognitive recovery | Post-surgery (7 days after surgery) | Mini Mental State Examination (MMSE) |
| Postoperative cognitive dysfunction - neurocognitive disorder | Post-surgery (90 days after surgery) | Mini Mental State Examination (MMSE) |
| Preoperative cognitive function II | Pre-surgery (within 10 days before) | Montreal Cognitive Assessment (MoCA) test |
| Postoperative cognitive dysfunction - delayed cognitive recovery II | Post-surgery (7 days after surgery) | Montreal Cognitive Assessment (MoCA) test |
| Postoperative cognitive dysfunction - neurocognitive disorder II | Post-surgery (90 days after surgery) | Montreal Cognitive Assessment (MoCA) test |
| Preoperative cognitive function III | Pre-surgery (within 10 days before) | The Telephone Interview for Cognitive Status (TICS) |
| Postoperative cognitive dysfunction - delayed cognitive recovery III | Post-surgery (7 days after surgery) | The Telephone Interview for Cognitive Status (TICS) |
| Postoperative cognitive dysfunction - neurocognitive disorder III | Post-surgery (90 days after surgery) | The Telephone Interview for Cognitive Status (TICS) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Incidence of postoperative delirium | Delirium assessment CAM-ICU preoperatively (baseline) and postoperatively twice a day during the first seven days or until discharge | Delirium will be assessed postoperatively for seven days or until discharge |
| Neurological injury type I (stroke) | Post-surgery (until 30 days after surgery) | The incidence of neurological injury type I will be evaluated for 30 days |
| Duration of mechanical ventilation | Post-surgery (until 30 days after surgery) | The duration of mechanical ventilation will be evaluated |
| Length of stay at the intensive care unit (ICU) | Post-surgery (until 30 days after surgery) | The length of stay at the intensive care unit (ICU) will be evaluated |
| Length of stay at the hospital | Post-surgery (until 30 days after surgery) | The length of stay at the hospital will be evaluated |
| Incidence of mortality resulting from all causes | Post-surgery (until 30 days after surgery) | All causes of mortality will be assessed for 30 days |
Countries
Brazil
Contacts
PRINCIPAL_INVESTIGATORCarlos Galhardo, MD
Instituto Nacional de Cardiologia
Outcome results
None listed