Post-operative Delirium

1
Post-operative Delirium

• Kyle C. Moylan, MD
• Assistant Professor of Clinical Medicine
• University of Missouri - Columbia

2
Background

• Delirium is common
• Delirium is often unrecognized
• Delirium is life-threatening
• Delirium is potentially predictable and
  preventable

3
Consequences

• Increased morbidity
• Increased mortality
• Increased costs
• Often a trigger of a downward spiral resulting
  in loss of independence, disability, and
  institutionalization

4
Delirium is Common

• Complicates the course of 20 of the 12.5 million
  patients over age 65 hospitalized every year
• Prevalence at admission 14-24
• Incidence during hospitalization 6-56
• Post-operative incidence 15-53
• ICU incidence - 70-87
• Incidence in post-acute care - 60

5
Delirium is Costly

• Adds 2500 to hospitalization per patient
• Accounts for 6.9 billion of Medicare hospital
  expenditures
• Increases cost for institutionalization,
  rehabilitation, home health services, and
  informal caregiving

6
Delirium is Underdiagnosed

• Diagnosis is clinical
• Requires careful bedside evaluation and cognitive
  assessment
• Fluctuating nature
• Confused with dementia
• Significance underappreciated
• Diagnosis is not considered or sought

7
Delirium Diagnostic Criteria

• Confusion Assessment Method (CAM)
• Requires -
• Acute Onset and Fluctuating Course
• Inattention
• AND Either
• Disorganized thinking OR
• Altered Level of Consciousness
• Sensitivity 94-100
• Specificity 90-95
• Used as gold standard in almost every study
• Only or so does not distinguish levels of
  severity
• CAM-ICU has also been developed

Inouye SK. Ann Intern Med 1990
8
Confusion Assessment Method

• CAM positive IF 1 and 2, plus 3a or 3b
• 1. Acute Onset and Fluctuating Course
• Is there evidence of an acute change in mental
  status from the patients baseline?
• Did the (abnormal) behavior fluctuate during the
  day (tend to come and go, or increase and
  decrease in severity)?
• 2. Inattention
• Did the patient have difficulty focusing
  attention (e.g. being easily distractible) or
  have difficulty keeping track of what was being
  said?
• 3a. Disorganized Thinking
• Was the patients thinking disorganized or
  incoherent such as rambling or irrelevant
  conversation, unclear or illogical flow of ideas,
  or unpredictable switching from subject to
  subject?
• 3b. Altered Level of Consciousness
• Overall, how would you rate this patients level
  of consciousness? (alert normal, vigilant
  hyper-alert, lethargic drowsy, easily
  aroused, stupor difficult to arouse, or coma
  un-arousable). Positive for any answer other
  than alert.

9
Delirium subtypes

• Hyperactive
• More easily recognized
• Tends to be more severe and associated with worse
  outcomes
• Hypoactive
• Less recognized but more common
• up to 70 of cases in post-hip fracture repair
• Can coexist in a single patient over time

10
Etiology

• Complex interaction of the patient, predisposing
  and precipitating factors
• More susceptible patients may require minimal
  insult
• Less susceptible patients will require more
  substantial insults
• Often multifactorial
• Pathophysiology poorly understood

11
Risk Factors for Post-Op Delirium

• Older age
• Cognitive impairment
• Functional impairment
• Decreased post-op hemoglobin
• Markedly abnormal Na, K, glucose
• BUN/Cr gt18
• Alcohol abuse
• Noncardiac thoracic surgery
• Aortic aneurysm surgery
• History of delirium
• Preoperative use of narcotics
• Low postoperative oxygen saturation
• History of cerebrovascular disease
• Untreated pain

Marcantonio JAMA 1994 Kalisvaart J Am Geriatr
Soc 2006
12
Drugs Implicated in Post-Op Delirium

• Anticholinergic medications
• Diphenhydramine, antispasmodics, TCAs,
  antiemetics
• Opiates
• Meperidine
• Benzodiazepines
• Antiparkinsonian drugs

13
Evaluation

• Physical Exam
• Blood sugar, pulse oximetry
• Targeted evaluation for underlying causes
• Exclude focal neurologic process
• Electrolytes, CBC, LFTs, urinalysis, ECG, PCXR,
  ABG
• Non-constrast head CT in select patients
• Patients with trauma, anticoagulants, metastatic
  disease, focal neuro findings or unable to
  complete adequate neuro exam
• EEG rarely helpful

14
Quick Mental Status Screen
15
Six Item Screener

• Questions
• What year is this?
• What month is this?
• What day of the week is this?
• Three item recall (1 minute) 
• Apple
• Table 
• Penny
• Total possible

• Point Value
• 1
• 1
• 1
• 1
• 1
• 1
• 6

16
Delirium Management

• Treat underlying causes
• Dont stop looking after finding one potential
  cause
• Supportive Care and Environment
• Targeted symptom-based treatment
• First have to make the diagnosis

17
Supportive Measures

• Remove unnecessary intrusions
• Indwelling urinary catheters, telemetry, IVs
• Avoid interrupting sleep
• Are the 3am vitals really needed for this
  patient?
• Sensory Aids (hearing aids, glasses)
• Family support
• Early mobilization, avoid restraints
• Provide reorientation (view of clock, calendars,
  familiar objects)
• Adequate lighting and temperature
• Include Fall Prevention protocols

18
Interventions

• Numerous studies showing successful
  multifactorial interventions to prevent and
  reduce the severity of delirium (Inouye et al.
  NEJM 1999)
• Generally address non-pharmacologic factors
• Sensory enhancement, hydration, mobilization,
  improved sleep, avoiding problem medications
• Difficult for a single person to implement
• Often led by teams of geriatricians, nurse
  partners, others
• May be part of an ACE unit

19
Pharmacologic Management

• Usually NOT indicated
• Reserve for patients whose symptoms threaten
  their own safety or that of others
• May be a substitute for physical restraints
• Oral therapy is preferred when possible
• Stopping medications may be more effective
• Outcomes of intervention studies are disappointing

20
DR. NO Approach

• D Describe the behavior, Document
• R Reason for the behavior
• N Non-pharmacologic management
• O Order medications last
• Assess the effect

21
Benzodiazepines

• NOT first line therapy
• May paradoxically worsen delirium
• Implicated as etiology of delirium in many
  patients
• Benzo use predicts development of delirium in
  post-op and ICU patients
• Can cause oversedation or respiratory depression
• Lorazepam 0.5-1.0mg orally, repeated every 4H
  as needed

22
Trazadone

• No controlled studies
• Preferred by some experts
• May cause oversedation
• 25-50mg orally at bedtime, plus every 4-6H as
  needed

23
Typical Antipsychotics

• Haloperidol is the drug of choice
• Effective in RCTs
• 0.5-1.0mg oral BID or at bedtime
• Repeat Q4H PRN
• Peak effect 4-6H
• Same dose can be given IM with peak effect in
  20-40 minutes
• IV not FDA approved and should be avoided
• EPS, prolonged QT. Contraindicated in PD pts

24
Haloperidol Prophylaxis for Elderly Hip-Surgery
Patients at Risk for Delirium A Randomized
Placebo-Controlled Study (Kalisvaart KJ et al.
J Am Geriatr Soc. 2005531658-1666)

• Patients - 430 pts. in the Netherlands
• Aged 70 and older at risk for delirium
• Mostly elective hip replacements (75)
• Intervention Haloperidol 1.5mg/daily or
  placebo.
• Started on admit and continued to POD 3.
• All patients with geriatrics consult.
• Results No difference in rate of delirium
  (15.1vs. 16.5)
• Decreased severity and duration (5.4 vs 11.8
  days)
• Decreased LOS (17.1 vs 22.6 days)
• No adverse effects of haloperidol were noted
• Limitations
• Lower than expected incidence of delirium
  (underpowered)
• Cognitively intact elective surgery patients
• Geriatrics consultation may have benefited both
  groups
• LOS longer than most US hospitals for this surgery

25
Atypical Antipsychotics

• Little data available but frequently used
• No evidence of superiority to haloperidol
• Concerns about increased risk of death in studies
  of dementia related behavioral problems
  (Schneider et al, JAMA 2005)
• Typical doses
• Risperidone 0.5 mg BID
• Olanzapine 2.5-5.0 mg daily
• Quetiapine 25 mg twice daily

26
Post-Discharge Care

• Delirium may persists for weeks or even months
• Should have regular follow-up of mental status
  until back to baseline
• Diagnosis and current mental status needs to be
  communicated to post-acute physician (and
  nursing)
• Poorer rehab outcomes
• 30 Rehospitalized from post-acute facilities
  (Marcantonio JAGS 2005)
• Risk of new diagnosis of dementia increased at
  least threefold
• 18 at one year (vs 5) (Rockwood Age Ageing
  1999)
• 69 at five years (vs 20) (Lundstrom JAGS 2003)
• Likely to have substantial long term needs
• Only 1/3 will still live independently at 2 years
  (McCusker CMAJ 2001)

27
Prevention Elective Surgery

• Add to pre-op evaluation for elderly pts
• Baseline MMSE
• Get family and caregivers involved
• Bring glasses, hearing aids to hospital
• Medication review
• Discuss with anesthesia

28
Conclusions

• If you arent making the diagnosis frequently,
  look harder
• Try using a simple screen for cognitive
  impairment for the next month
• Set an example for learners by evaluating for
  delirium and cognitive impairment
• Include delirium in the perioperative management
  of your patients
• Document and communicate the problem with other
  providers

29
References

• Inouye SK. Current Concepts Delirium in Older
  Persons. N Engl J Med. 20063541157-1165a.
• Amador LF, Goodwin JS. Postoperative Delirium in
  the Older Patient. J Am Coll Surg.
  2004200767-773.
• Inouye SK, et al. Clarifying confusion The
  Confusion Assessment Method. A new method for
  detection of delirium. Ann Intern Med. 1990113
  941-948.
• Callahan CM, Unverzagt FW, Hui SL, Perkins AJ,
  Hendrie HC. Six-item screener to identify
  cognitive impairment among potential subjects for
  clinical research. Med Care. 200240 771-781.
• Marcantonio ER, Goldman L, Mangione C, et al. A
  Clinical Prediction Rule for Delirium After
  Elective Noncardiac Surgery. JAMA.
  1994271134-139.
• Kalisvaart KJ, Vreeswijk R, deJonghe JF et al.
  Risk Factors and Prediction of Postoperative
  Delirium in Elderly Hip-Surgery Patients
  Implementation and Validation of a Medical Risk
  Factor Model. J Am Geriatr Soc. 200654817-822.
• Marcantonio ER, Juarez G, Goldman L, et al. The
  Relationship of Postoperative Delirium with
  Psychoactive Medications. JAMA.
  19942721518-1522.
• Inouye SK, Bogardus ST, Charpentier PA, et al. A
  Multicomponent Intervention to Prevent Delirium
  in Hospitalized Older Patients. N Engl J Med.
  1999340669-676.
• Kalisvaart KJ et al. Haloperidol Prophylaxis for
  Elderly Hip-Surgery Patients at Risk for
  Delirium A Randomized Placebo-Controlled Study.
  J Am Geriatr Soc. 2005531658-1666.
• Rockwood K, Cosway S, Carver D, et al. The Risk
  of Dementia and Death after Delirium. Age
  Ageing. 199928551-556.
• Lundstrom M, Edlund A, Bucht G, et al. Dementia
  after Delirium in Patients with Femoral Neck
  Fractures. J Am Geriatr Soc. 2003511002-1006.
• McCusker J, Cole M, Dendukuri N, et al. Delirium
  in Older Medical Inpatients and Subsequent
  Cognitive and Functional Status a Prospective
  Study. CMAJ 2001165575-593.
• Marcantonio ER, Kiely DK, Simon SE, et al.
  Outcomes of Older People Admitted to Postacute
  Facilities with Delirium. J Am Geriatr Soc.
  200553963-969.