Study of Prevention of Postoperative Delirum to Reduce Incidence of Postoperative Cognitive Dysfunction (DelPOCD)

Study of Prevention of Postoperative Delirum to Reduce Incidence of Postoperative Cognitive Dysfunction

The Influence of Non-medication-based Prophylaxis of Postoperative Delirium on Postoperative Delirium and Cognitive Deficit

Postoperative cognitive dysfunction describes a condition where cognitive functions such as attention, perception, concentration, learning, abstract thinking and problem solving are impaired postoperatively. These changes can be resolved after weeks and months, but in some cases may be permanent. The aetiology is multifactorial. One risk factor for developing POCD is the occurrence of postoperative delirium. A total of 638 consecutive patients will be enrolled in the study. Patients will be followed up at 7 days, 3 months and 1 year postoperatively. The cognitive function will be tested and compared to tests done before surgery. Postoperatively (from the day of operation until the 7th day and except of day 6) the grade of sedation; agitation; signs of delirium; pain; cardiac; respiratory; renal and infectious complications will be recorded. As possible influencing factors, the investigators will document diagnosed depression; comorbidities; intraoperative blood loss; length of hospital stay; 1-year-mortality; number of operations/anaesthetics undergone after the initial operation. Parameters that could trigger either depressive symptoms, neurocognitive dysfunction, anxiety, fatigue or lack of concentration will be recorded. These include: anaemia, hypercalcaemia, thyroidal gland hormones, electrolytes, creatinine, urea, glomerular filtration rate, cortisone therapy and adrenal cortical insufficiency.

The methods include a neuropsychological test battery: TAP 2.3 (attention), Trail Making Test (TMT )A+B (attention), Digit span (memory), (Visual Learning and Memory Test (VLMT) (memory), Regensburgerwortfluessigkeitstest/fluency (RWT) subtests (executive function), Mehrfach-Wortschatz-Intelligenztest/vocabulary (MWT-B) (premorbid IQ). Other measures are Hospital Anxiety and Depression Scale (HADS-D) (depressive symptoms and anxiety), Mini Mental State Examination (MMSE) 2 (dementia), Confusion Assessment Method (CAM-ICU) (delirium), Richmond Agitation and Sedation Scale (RASS) (sedation and agitation), Numeric Rating Scale (NRS) (pain) and Short Form Health Survey (SF-12) (health related quality of life).

The treatment group will receive monitoring and prophylaxis of delirium. The study arm designed to prevent delirium incorporates reorientation (watches, calendar, family photos, use of hearing aids, glasses and dentures, cognitive stimulation (newspaper, magazines, radio, television), early mobilisation, early enteral nutrition, early removal of drains or catheters, normalizing sleep-awake-rhythm.

The standard group will receive standard monitoring and standard treatment. The indication, choice and dosage of the medication used to treat delirium will be at the discretion of the ward doctor and will not be influenced by this study. The chosen medication as well as its dosage will be documented.

daily documentation of cardiac complications (central venous oxygen saturation, myocardial infarction, acute heart failure, others)

daily documentation of parameters mirroring the immune answer (C-reactive protein, leukocytes, procalcitonin)

The Hospital Anxiety and Depression Scale (HADS-D) is used to measure depressive symptoms. The 7 items are answered on a 4-point scale from 0 to 3 with a scale score varying between 0 and 21 (0-7 = normal, 8-10 = borderline, 11-14 = severe depressive symptoms, >15 very severe depressive symptoms).

Inclusion Criteria: Age > 60 years Cardiac surgery (on-pump/off-pump, standard/minimal invasive) Written informed patient's consent Exclusion Criteria: Non-German speaking or not their first language Illiteracy Mental disability Non-corrigible vision impairment Non-corrigible hearing impairment Illegal substance abuse (current or past history) Alcohol abuse (current or past history) Chronic benzodiazepine use Psychosis (current or past history) Parkinson Disease Dementia Multiple sclerosis Epilepsy (current or past history) Cerebral tumor (current or past history) Apoplexy or intracranial bleeding (current or past history) Severe traumatic brain injury (current or past history) Severe liver disease (Child Pugh B, C, liver insufficiency) Severe kidney disease with dialysis Mini Mental Status Examination < 24 points

Department of Anaesthesiology and Intensive Care Medicine, University Hospital Hamburg Eppendorf, Univ.-Prof. Dr. med. Alwin E. Goetz and Prof. Dr. med. Christian Zoellner