Postoperative cognitive dysfunction a neverending story Adela Hilda Onuţu, MD, PhD Cluj-Napoca, Romania adela_hilda@yahoo.com
No conflict of interest
Contents Postoperative cognitive dysfunction (POCD) Epidemiology Pathophysiology Evaluation Prevention Role of regional anaesthesia in its prevention
Let s pretend 85 yr, female, ASA III 162 cm, 70 kg Diabetes mellitus Arterial hypertension Asthma History of thrombosis
What choices do we have? General anaesthesia? Spinal or continuous spinal anaesthesia? Epidural anaesthesia? Combined lumbar block and sciatic parasacral block? Total intravenous anaesthesia?
What would you choose?
Postoperative cognitive dysfunction (POCD)- definition = cognitive impairment arising after a surgical procedure 70% die within 5 years Impairment of: memory intellectual performance ability to combine tasks psychomotor dexterity Monk T, Curr Opin Crit Care 2011
Diagnosis Diagnosis requires both pre- and postoperative psychometric testing Differential diagnosis: Delirium Central anticholinergic syndrome Dementia Akinetic syndrome
Incidence of POCD (in non-cardiac surgery) Age (yr) Incidence 18-39 36.6% 40-59 30.4% >60 41.4% Monk TG, Anesthesiology. 2008;108:18 30.
Why it is so important? One week after surgery 60-80 yr 26% 40-60 yr 19% After 3 month persistent POCD 10% persistent POCD 6%
Never been the same after his/her surgery!
8.5 yr follow-up in ISPOCD study POCD was associated with: Higher mortality Earlier retirement Higher utilization of financial assistance Steinmetz et al; Anesthesiology 2009; 110:548 555
Pathophysiology Surgery systemic inflammation )L 1, 6, TNF) neuroinflammation )L 18 Anaesthetics have independent roles
Risk factors Age Low regional cerebral oxygen saturation Silent brain ischemia Subclinical cognitive impairment Anxiety Depression Alcohol abuse Visual and hearing impairment Extensive surgery
Anesthetics and POCD No differences - general and regional The shorter the duration of the anaesthetic agent, the shorter is the duration of POCD Rundshagen I, Dtsch Arztebl Int. 2014
Intraoperative arterial pressure!!!! significant relationship between minimum intraoperative MAP and decline in cognitive function 1 day and 1 month after surgery. Yocum GT et al. Anesthesiology 2009;110: 254-61
General anaesthesia is associated with persistent changes in gene expression in brain for at least 72 hours drugs administered interact with the cerebral cholinergic system Laalou et al. J Chir 2008; 145: 323-30 Short duration general anaesthesia in mice upregulation 6/20 gene, up to day 4 after surgery Pekny et al. Acta Anaesth Scand 2014; 58: 1127-33
Nicotinic acethylcholinic receptors The central essential mechanism of POCD Agonists - improve Atracurium Laudanosine Antagonists - impair Volatile agents Ketamine Benzodiazepines at high C% Propofol at high C% Etomidate at high C% Remifentanil do not interfere with this receptor Fodale et al. Anesthesia 2010; 65: 388-95
Don t forget our patient!
Role of anaesthetics in neuroinflammation Direct SNC neurotoxicity Alteration in calcium homeostasis Systemic direct inflammatory effect Suppression of neural stem cell function Acceleration of endogenous neurodegenerative processes Caspase activation Apoptosis Increase β-amiloid formation Fodale et al. Anesthesia 2010; 65: 388-95
BIS Monitoring Deep anesthesia corelates with high incidence of delirium and POCD BIS guided depth of anaesthesia decreased delirium and POCD Chang ;J Neurosurg Anesthesiol 2013 Or only delirium! Radtke ; Br J Anaesth 2013
Regional analgesia and opioid consumption??? 7 RCT femoral nerve block vs no block resulted in a significant difference in additional pain medication use, favoring nerve blocks (p = 0.006) Abou-Setta AM et al. Ann Intern Med. 2011;155:234-45.
Does anaesthetic technique really 3 separate trials coronary o angiography (percutaneous diagnostic procedure) -sedation o major noncardiac surgery (total hip joint replacement) - general anesthesia o coronary artery bypass graft surgery -general anesthesia matter for POCD? Results: POCD at 3 months was independent of the nature or the type of procedure cardiovascular risk factors were not predictive of POCD after any procedure Evered, Anesth Analg 2011
Even sedation plays its role POCD relates to midazolam administration, even as sedation Dressler, EJA, 2007 Perioperative dexmedetomidine treatment is associated with significantly better neurocognitive function postoperatively in comparison with both saline controls and comparator anaesthetics (predominantly midazolam Man Y, Clin Exp Pharmacol Physiol, 2015
Procedural sedation Investigation to evaluate postprocedure cognitive function 3 distinct standard sedation regimens Propofol, propofol+fentanyl, midazolam +fentanyl Results: propofol alone provides adequate sedation with minimal effects on POCD Watkins, AANA Journal, 2014
Meta-analysis 21 RCT Searched the influence of general, regional, or a combination of anesthesia on POCD Result: general anesthesia may increase the risk of developing POCD Regional anaesthesia is recommended Mason SE, J Alzheimers Dis. 2010, 22: 67-79
POCD evaluation- Psychometric testing Trail making test A & B ability to perform tasks Digit Span Test short memory Rey auditory verbal learning test word learning The grooved pegboard test manual dexterity Cognitive failure questionnaire -25 item self assessment anxiety & depression
Mini Mental State Examination (MMSE)- max 30 points Temporal and spatial orientation Retentiveness Recollection Attention and correctness Language Ability to write and draw
MMSE form - The Hartford Institutehttps://www.mountsinai.on.ca/care/psych/on-call-resources/on-callresources/mmse.pdf
Measures to reduce POCD Effective postoperative pain management Antiinflammatory Regional analgesia Early discharge- fast track reduce at 50% POCD at 1 week after surgery Zywiel ; Med Sci Monit 2014; 20: 1908 1912
POCD with orthopaedic surgery Incidence of POCD in arthroplastic surgery 72% at 6 days 30% at 3 month Scott at al. J Arthroplasty 2014; 29: 261-7
Why is that? age thromboembolic events influence of anaesthesia influence of pain therapy in the postoperative period cerebral fat embolization (40-60%)
Back to our patient Lumbar plexus block preoperatively Spinal anaesthesia low dose bupivacaine Target: hemodynamics stability Minimal sedation
Conclusions POCD affects outcome and postoperative mortality Inflammation and neuroinflammation have an important role in pathogenesis No differences between general and regional anaesthesia Postoperative opioid analgesia increases the incidence of POCD
Thank you for attention!