POSTOPERATIVE ALTERATION IN MENTAL STATUS LATEST.pptx

POSTOPERATIVE ALTERATION IN MENTAL STATUS

1. POSTOPERATIVE ALTERATION IN MENTAL STATUS PRESENTER: FARAH NABILAH SUPERVISOR: DR AZWANI

2. INTRODUCTION Postoperative alteration in mental status following general anaesthesia can be manifested in various ways, such as: Confusion, agitation, restlessness, incoherence of speech, hallucinations Disorientation to time, place, person or events Inability to follow simple commands or instruction Failure to recover consciousness or responsiveness within the expected time frame following general anaesthesia

3. INCIDENCE C an occur up to 30 days post procedure 14% in the general medical wards 82% in the intensive care unit Surgeries strongly associated with delirium up to 50% of the patients postoperatively - vascular - orthopedic - cardiac surgery

4. IMPLICATIONS Increase risk of harm to patient and staff – pull out catheter, drain, physical assault Prolong stay in recovery bay – difficult to discharge patient to ward Increase risk of reintubation - anticipate admission to ICU Increase duration of hospital stay Increase healthcare cost Increase risk of developing hospital acquired infection Reduce patient’s / family members’ satisfaction

5. CLINICAL FEATURES CATEGORIES 1) Hyperactive – agitated, aggressive, and combative 2) Hypoactive – anhedonia, decreased alertness 3) Mixed

6. SYMPTOMS Change in level of arousal – drowsiness or decreased arousal or increased arousal with hypervigilance Delayed awakening from anesthesia Abrupt change in cognitive function (worsening confusion over hours or days), including problems with attention, difficulty concentrating, new memory problems, new disorientation Difficulty tracking conversations and following instructions

7. SYMPTOMS Disorganized thinking and speech, difficult to follow, slow, or rapid Quick-changing emotions – easy irritability, tearfulness, uncharacteristic refusals to engage with postoperative care Expression of new paranoid thoughts or delusions (e.g., fixed false beliefs) New perceptual disturbances (e.g., illusions, hallucinations)

8. SYMPTOMS Motor changes – slowed or decreased movements, purposeless fidgeting or restlessness, new difficulties in maintaining posture such as sitting or standing Sleep/wake cycle changes – sleeping during the day and/or awake and active at night Decreased appetite New incontinence of urine or stool Fluctuating symptoms and/or level of arousal over the course of minutes to hours

9. RISK FACTORS PREDISPOSING FACTORS PRECIPITATING FACTORS Age Cognitive impairment Complex comorbidities Sleep disruption Emergency surgery Significant intraoperative blood loss Poorly controlled pain

10. CAUSES susceptible patients drug causes metabolic and endocrine causes postoperative problem intraoperative complications resulting in cerebral ischemia or cerebral edema neurologic causes

11. SUSCEPTIBLE PATIENTS All age group – elderly or demented patient; pediatrics (ADHD, autism) Intoxication with alcohol or drugs Decreased level of consciousness due to raised intracranial pressure or metabolic derangements such as head injury, intracranial space-occupying lesion, cerebral edema, uremic or hepatic encephalopathy Significant liver or renal impairment, giving rise to prolonged duration of action of anesthetic drug

12. Increased sensitivity to centrally depressant drugs, or prolonged duration of action of such drugs to various reasons Examples of drugs include premedicant drugs, anaesthetic agents, patient's own medication (e.g., tricyclic antidepressants, sedatives), recreational drugs, alcohol Absolute or relative drug overdose Idiosyncratic response to ketamine, droperidol , scopolamine in the elderly DRUG CAUSES

13. METABOLIC AND ENDOCRINE CAUSES Hypoxia, hypercarbia, acidosis Electrolyte imbalance involving sodium, potassium, magnesium or calcium Hypo- or hyperosmolality Hypo- or hyperglycemia Hypothyroidism Hepatic or uremic encephalopathy Malignant hyperthermia Hypothermia

14. NEUROLOGIC CAUSES Raised intracranial pressure due to cerebral edema or haemorrhage Cerebrovascular accident: thrombotic, embolic, haemorrhagic Hypoxic encephalopathy

15. INTRAOPERATIVE COMPLICATIONS RESULTING IN CEREBRAL ISCHEMIA OR CEREBRAL EDEMA Prolonged hypotension secondary to hypovolemia, cardiac failure Pulmonary embolism (air, carbon dioxide, fat, amniotic fluid, thrombus) Water intoxication, hyponatremia in TURP syndrome Hypoxia, hypercarbia, hypoxic encephalopathy Cerebrovascular accident: thromboembolic or haemorrhagic stroke

16. POSTOPERATIVE PROBLEMS Hypoxia, hypercarbia due to various causes, e.g., hypoventilation, airway obstruction Respiratory insufficiency Inadequate pain relief Bladder distension Metabolic or endocrine abnormalities such as hypoglycemia, electrolyte imbalance, acidosis, dehydration, hypothyroidism Hypovolemia secondary to incomplete surgical hemostasis or inadequate volume resuscitation Hypothermia Incomplete reversal of neuromuscular blockade Coronary events: acute myocardial infarction or angina

17. Inadequate reversal of neuromuscular blockade may be mistakenly diagnosed as failure to regain consciousness because the patient may be conscious but appears drowsy as a result of ocular and bulbar muscle weakness. Possible causes for incomplete reversal of neuromuscular blockade Absolute or relative overdosage of neuromuscular blocking drugs Patients with neuromuscular disease, severe hepatic or renal impairment Potentiation of neuromuscular blockade by acidosis, hypothermia, electrolyte imbalance (hypokalemia, hypermagnesaemia, hypocalcemia) Congenital or acquired pseudocholinesterase deficiency (for suxamethonium apnoea)

18. PREVENTION PREOPERATIVE Identify patients at risk Avoid excessive preoperative sedation especially in the elderly and ill patient Nutritional and fluid repletion enhancement - avoid prolonged fasting and maintenance of hydration Treat and optimize metabolic, endocrine or neurologic abnormalities before surgery Medication review and appropriate medication management Explain to patient and family member risk of developing post operative delirium in susceptible patient

19. PREVENTION INTRAOPERATIVE Prompt and aggressive resuscitation in the event of any intraoperative complications Careful titration of anesthetic drugs to avoid overdose Maintain hemodynamic stability Mode of anesthesia - opt for local or regional anesthesia instead of general anesthesia if feasible

20. ANAESTHESIA TECHNIQUE Evidence suggests that the use of bispectral index (BIS)–guided anesthetic care is associated with a reduced incidence of postoperative delirium - avoiding excessively deep anesthesia Two randomized controlled trials demonstrated that in the group randomized to BIS-guided care (between 40-60), there was a reduction in either propofol or volatile agent administered, and the incidence of postoperative delirium as compared with routine care This suggests that avoiding excessive depth of anesthesia is an important preventative strategy for the management of delirium The exact mechanism linking the depth of anesthesia to postoperative delirium remains unclear

21. Benzodiazepines have been implicated in the development of delirium, with exposure to midazolam identified as a risk factor for delirium in postsurgical and intensive care patients The routine use of benzodiazepine premedication should be discouraged, except in cases in which there is preexisting anxiety and benzodiazepine or alcohol withdrawal

22. Ketamine, an N-methyl-D-aspartate antagonist with psychoactive properties, showed promising benefit for reduction in delirium when given prophylactically in a small trial in cardiac surgery, but this has not been supported by larger randomized control trials Subanesthetic doses of ketamine have been demonstrated to reduce postoperative markers of inflammation, pain, and opioid consumption as well as having an antidepressant effect A large, multicenter trial that randomized patients to either 0.5mg/kg, 1.0 mg/kg, or normal saline did not demonstrate a statistically significant difference in delirium, but there were higher rates of hallucinations and nightmares reported with each increased dose of ketamine

23. Dexmedetomidine ( Precedex ), an a-2 agonist, has been demonstrated to reduce the incidence of delirium in patients older than 65 years after noncardiac surgery when given prophylactically (0.1 g/kg/h) to patients admitted to the intensive care unit  

24. PREVENTION POSTOPERATIVE Adequate pain control – use multimodal regime Sensory enhancement – ensuring glasses, hearing aids, or listening amplifiers Encourage mobility if appropriate – avoid strict bed rest Employ reorientation strategies – involve family members if available Sleep enhancement – daytime sleep hygiene, relaxation, nonpharmacological sleep protocol, and nighttime routine

25. MANAGEMENT Attempt to communicate with the patient Attempt to rouse the patient if he/she is unresponsive, or talk to the patient if he/she able to vocalize Use verbal and tactile stimulation, not forceful or painful prodding If the patient is responsive, he/she may be able to indicate what the problem is: possibly pain at the surgical site, chest pain, distended bladder, cold or respiratory difficulty. Treatment can be tailored to the specific complaint

26. If the patient is unresponsive, totally confused or disoriented: Quickly check the ABCs: ensure that oxygenation and ventilation are not compromised Maintain airway support and perform suction to clear secretions as required, checking for presence of gag reflex in the process Check respiratory pattern, oxygen saturation, blood pressure, heart rate and DXT Administer supplemental oxygen by face mask: this may be difficult in a confused, combative patient; oxygen delivered via nasal prongs may be better tolerated Support ventilation or re-intubate if respiration is inadequate Resuscitate with intravenous fluids, blood or inotropic agents if indicated

27. If the patient is still intubated and connected to the anaesthetic machine, check that all anaesthetic drugs are discontinued Increase oxygen flow to hasten elimination of inhalational anaesthetics Check expired anaesthetic concentrations on anaesthetic agent concentration monitor

28. Assess adequacy of recovery from neuromuscular blockade Inadequate recovery is characterized by jerky, uncoordinated movement with feeble attempts of respiration Assess clinically and by means of peripheral nerve stimulator, using train of four (TOF) count, TOF ratio or double burst stimulation (DBS) Administer an additional dose of reversal agent if indicated Support ventilation while the patient regains muscle power; consider additional sedation if this period of recovery is expected to be prolonged: it is terrifying for the patient to be fully awake but unable to breathe

29. Conduct a careful neurological examination - in patient with mild altered mental status or hypoactive (unable to extubate in OT) Check pupil size and reaction to light, gag and cough reflex, response to tactile or pain stimulus, muscle power, muscle tone, tendon reflexes Look for any focal neurological signs Consider referral to a neurologist May need radiological intervention – CT brain May require ICU admission

30. Review the anesthetic history Review the dose and timing of drugs administered during the course of the anesthetic Check syringes and ampoules to rule out the possibility of wrong drug administration Note any adverse intraoperative events such as hypotension, cardiac dysrhythmias, hypovolemia and cardiac arrest Check ECG if myocardial ischemia is suspected

31. Bedside and laboratory investigations Obtain blood samples for ABG, DXT, electrolyte concentrations (sodium, potassium, calcium), hematocrit, urea, serum osmolarity 12-lead ECG if myocardial ischemia is suspected Request portable chest X-ray if lung pathology is suspected

32. Treatment for specific disorder Hypoglycemia: 50% dextrose bolus, followed by infusion of dextrose solution Hyperglycemia: intravenous hydration with normal saline and insulin treatment Hypo-osmolarity: normal saline, IV frusemide Hyponatremia: normal saline, consider hypertonic saline

33. Consider the use of antidotes for reversal of specific drugs For opiods : IV naloxone 0.1mg increments titrating to effect, maximum 0.4mg. Beware of risks of pulmonary edema even with small doses For benzodiazepines: IV flumazenil 0.2mg over 15 seconds, repeat until effective (maximum 1mg in 5 minutes, 3 mg in 1 hour) For anticholinergic agents: IV physostigmine 1mg, maximum 4mg

34. If the patient is confused or combative, the tendency is to administer sedative drugs to quieten the patient Sedation should not be given unless the underlying cause has been identified It not only masks neurological signs and confuses further neurological assessment, it may also be dangerous in patients with respiratory insufficiency or shock due to any cause Further management in ICU or HDU may be indicated if no improvement occurs

35. AVOID STRAINING PATIENT – last option

36. REFERENCES Lee, C. Y. (2006). Manual of anaesthesia (pp. 855-859). McGraw Hill. Postoperative Cognitive Disorders: Postoperative Delirium and Postoperative Cognitive Dysfunction Samuel Fitzpatrick1. (2020, May 14). Postoperative cognitive disorders: Postoperative delirium and postoperative cognitive dysfunction. WFSA Resource Library.