Impact of Cerebral Monitoring on Neurologic Outcome in Cardiac Surgery
Condition: Cardiac Surgical Procedures
Study type: Interventional

Summary: 
      Neurologic complications after cardiac surgery range over a wide spectrum including
      postoperative delirium (PD), postoperative cognitive dysfunction (POCD) and cerebrovascular
      accidents (CVA). The incidence of these neurologic events varies depending on the type of
      surgery and the population studied. The incidence of PD and/or POCD is further influenced by
      the type of the neurologic tests used. Moreover, the timing of these tests seems to influence
      the results. Intraoperative cerebral monitoring is gaining importance in the anesthesia
      field. Recent findings have pointed out that cerebral hypoperfusion on one hand and deep
      levels of anesthesia on the other hand are major sources of adverse neurological outcomes,
      both of which can be detected with different non-invasive cerebral monitors.The present
      investigators are currently using the NeuroSENSE®, a processed electroencephalogram (pEEG)
      monitor together with cerebral near-infrared spectroscopy (NIRS) on a daily basis in every
      cardiac patient.

      This large, prospective, observational study will investigate whether the short- and mid-term
      neurologic outcome of adult patients undergoing cardiac surgery are in line with observations
      made on the basis of the pEEG monitor NeuroSENSE® and cerebral NIRS.
    

Detailed description: 
      Whilst the incidence and the perioperative management of neurological complications after
      cardiac surgery may vary, they share some common risk factors for their occurrence: advanced
      age, cardiovascular morbidity including peripheral vascular disease, diabetes, previous
      stroke, preoperative cognitive impairment and dementia.As most of these factors are not
      modifiable at the time of surgery, conditions that can be controlled in the perioperative
      period should deserve more focus to prevent the occurrence of neurological problems.

      Intraoperative cerebral hypoperfusion is generally accepted as a worsening factor of
      neurological complications.Besides hypoperfusion states, an overdose of general anesthetics
      is among intraoperative factors that have been evoked to influence postoperative neurological
      complications.

      The main aim of this study is to know the incidence of POCD and PD in cardiac surgical
      population and to seek whether the presence and the duration of burst suppressions as
      detected by NeuroSENSE® on one hand and episodes of cerebral desaturation as detected by
      bilateral cerebral NIRS on the other hand are risk factors to develop these complications.
      The magnitude of burst suppression will be recorded as total Area Under the Curve (AUC) of
      burst suppression of each hemisphere. Cerebral desaturation is defined as AUC of 25% drop of
      oximetry values as compared to the preinduction values for each hemisphere. We will evaluate
      whether the concomitant presence of burst suppression together with cerebral oximetry
      desaturation can predict POCD and PD. Our study will be the first to analyze this point.

      Otherwise, with this study the investigators will look for any eventual agreement between the
      cerebral NIRS and the NeuroSENSE® monitor in terms of detecting cerebral abnormalities.
      Lastly, in line with previous observations, the investigators will actively look for any
      intraoperative EEG abnormalities and in particular any sustained pEEG asymmetry that appears
      together with burst suppressions.

      Although the study is observational any frontal severe EEG asymmetry together with the
      appearance of burst suppression will be carefully evaluated by an experienced
      anesthesiologist in reading and interpreting processed EEG monitor. The case will be
      discussed on an multidisciplinary basis and an eventual CT scan will be performed.In the
      absence of hemorrhage and if large cerebral vessel occlusion is identified, a catheter
      angiography with an eventual thrombectomy will be realized with the aim to extract the clot.
    

Intervention name(s): If any intraoperative EEG abnormality and/or asymmetry is detected a cerebral CT scan will be performed in the immediate postoperative period
Intervention type(s): Procedure
Intervention model: Single Group Assignment
Masking: None (Open Label)
Primary purpose: Diagnostic