Preoperative BAMCOG and Cortisol and Postoperative DeltaScan in AVR Patients (Aortic Valve Replacement)
Condition: Delirium; Cognitive Impairment; Cognitive Dysfunction; Cognitive Dysfunction, Postoperative; Delirium in Old Age; Postoperative Delirium
MeSH terms: Delirium; Emergence Delirium; Postoperative Cognitive Complications; Cognitive Dysfunction
Study type: Observational

Summary: 
      There is lack of attention to preoperative cognitive function and delirium in elderly who
      underwent surgery. The investigators are investigating different tools that can help to
      screen for cognitive dysfunction and delirium in the future.
    

Detailed description: 
      Background of the study:

      The mean age of surgical patients is rising worldwide and this is associated with more
      multi-morbidity. Especially geriatric patients who undergo surgery have a higher risk to
      develop Postoperative Cognitive Dysfunction or a Postoperative Delirium, which leads to
      higher morbidity and mortality after surgery and this leads to higher healthcare costs.

      A delirium is an acutely disturbed state of mind characterized by restlessness, illusions,
      and incoherence, occurring in intoxication, fever, and other disorders and can fluctuate over
      time. The hypoactive delirium, the most common type of delirium, is hard to recognize
      compared to the active delirium that is expressed by restlessness and agitation.

      Postoperative cognitive dysfunction is defined as a new cognitive impairment arising after a
      surgical procedure. Its diagnosis requires both pre- and postoperative psychometric testing.
      Its manifestations are subtle and manifold, depending on the particular cognitive domains
      that are affected, and therefore hard to recognize too.

      To assess preoperative cognitive function in large groups of patients, it's needed to have a
      simple and quick tool to screen. In this study, the investigators use the BAMCOG, which is a
      tool with 3 short games played on a tablet that can provide information about cognitive
      functioning. When writing this new study protocol, a validation study in which the BAMCOG is
      validated against the MoCA is running.

      Beside the BAMCOG, another instrument will be investigated. The DeltaScan is an EEG delta
      waves measurement to identify patients with a (hypoactive) delirium. Delta waves are slow
      brainwaves that have been seen in sedated patients and even inpatients with an active or
      hypoactive delirium. A study of Kimchi et al. studied whether routine clinical EEG findings,
      including slowing, are correlated with delirium severity in a heterogeneous population with
      various causes of altered mental status and found that generalized slowing on routine
      clinical EEG strongly correlates with delirium and may be a valuable biomarker for delirium
      severity (OR 7.4, 95% CI 3.8-14.4).

      A lot remains unclear about the biological mechanisms in the development of a delirium after
      surgery, although in literature are directions that inflammatory reactions and the
      neuro-endocrine system play an important role. That is the reason for investigating the
      relation between cortisol levels in blood, saliva and sweat and the development of
      postoperative acute encephalopathy.

      Objective of the study:

        1. The predictive value of the BAMCOG for developing postoperative delirium/postoperative
           acute encephalopathy in patients who underwent AVR surgery

        2. Concurrent validation of the BAMCOG with the MoCA

        3. The relation between cortisol levels in blood, saliva and sweat and the development of
           postoperative delirium/postoperative acute encephalopathy.
    

Intervention name(s): MoCA; BAMCOG; DeltaScan; Salivette; Pilocarpine iontophoresis
Intervention type(s): Diagnostic Test; Device; Diagnostic Test; Diagnostic Test; Diagnostic Test
Intervention description(s): MoCA test to identify Mild Cognitive Impairment; Three games, compared to the MoCA to identify Mild Cognitive Impairment; EEG to detect acute encephalopathy; To collect saliva for cortisol analysis; To collect sweat for cortisol analysis
Intervention MeSH terms: Pilocarpine
Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        50 patients 65 years or older who will undergo AVR-bio surgery