Clinical Decision-making:Why evidence is never

sufficient• EBM and the role of patient values

• physician values and life or death decisions

• patient values and physician values

• how might we elicit patient values?

Treatment of pneumonia• do antibiotics help in pneumococcal

pneumonia?

• 95 year old man, severely demented, incontinent, contracted, lives in long-term care facility

• contracts pneumococcal pneumonia

• should he receive antibiotics?

Ask

Acquire

Appraise

Apply

Act

Patient dilemma

Hierarchy of

evidence

Evidenceis not

enough

Clinical decision-making Clinical decision-making 20092009

Research evidence

Patient valuesand preferences

Clinical state and circumstances

ExpertiseExpertise

CaseCase• 75 y/o female admitted to the ICU with 75 y/o female admitted to the ICU with

urosepsis 10 days ago. She now requires urosepsis 10 days ago. She now requires two inotropes to maintain a mean arterial two inotropes to maintain a mean arterial pressure of 80 mm HG, is ventilator pressure of 80 mm HG, is ventilator dependent, comatose, and in acute dependent, comatose, and in acute oliguric renal failure. Her APACHE II score oliguric renal failure. Her APACHE II score is 38, suggesting a 10% chance of survival. is 38, suggesting a 10% chance of survival. Her past history includes long-standing Her past history includes long-standing depression, responsive to treatment. She depression, responsive to treatment. She has been walking with a cane due to a has been walking with a cane due to a chronic deformity from polio.chronic deformity from polio.

• She used to run the family manufacturing She used to run the family manufacturing business, which involved supervision of 10 people. business, which involved supervision of 10 people. Until just before admission, she continued to do Until just before admission, she continued to do the bookkeeping for the firm. She is single and the bookkeeping for the firm. She is single and lives alone in her own home. There are no known lives alone in her own home. There are no known written or verbal advance directives. The patient written or verbal advance directives. The patient has an older brother living in the United States, has an older brother living in the United States, with whom she has not spoken for years, and with whom she has not spoken for years, and whose current whereabouts are not known. There whose current whereabouts are not known. There are no other living relatives. A few friends visit her are no other living relatives. A few friends visit her in the ICU, but none want to be involved in in the ICU, but none want to be involved in decisions regarding her medical care.decisions regarding her medical care.

Management strategiesManagement strategies• 1. D/C inotropes and ventilator but continue 1. D/C inotropes and ventilator but continue

comfort measurescomfort measures• 2. D/C inotropes and other maintenance therapy 2. D/C inotropes and other maintenance therapy

but continue ventilator and other comfort but continue ventilator and other comfort measuresmeasures

• 3. Continue with current management but add 3. Continue with current management but add no new therapeutic interventionsno new therapeutic interventions

• 4. Continue with current management, add 4. Continue with current management, add further inotropes, change antibiotics, and the further inotropes, change antibiotics, and the like as needed, but do not start dialysislike as needed, but do not start dialysis

• 5. Continue with full aggressive management 5. Continue with full aggressive management and plan for dialysis if necessaryand plan for dialysis if necessary

Withdrawal of life Withdrawal of life supportsupport

Cook, Guyatt, JAMA. 1995Cook, Guyatt, JAMA. 1995• Cross sectional surveyCross sectional survey• Staff from 37 university affiliated Staff from 37 university affiliated

hospitals in 8 provinceshospitals in 8 provinces• 1361 ICU health care workers 1361 ICU health care workers

completed the surveycompleted the survey – 149 of 167 ICU attending staff149 of 167 ICU attending staff– 142 of 173 ICU house staff142 of 173 ICU house staff– 1070 of 1455 ICU nurses1070 of 1455 ICU nurses

• Overall participation rate 76%Overall participation rate 76%

Case DevelopmentCase Development• cases scenarios, variable factorscases scenarios, variable factors

– patient’s age (45 vs 75)patient’s age (45 vs 75)– prior cognitive function (highly functional vs alzheimer’s)prior cognitive function (highly functional vs alzheimer’s)– likelihood of surviving current episode (50% vs 10%)likelihood of surviving current episode (50% vs 10%)– likelihood of long term survival (50% 1yr mortality breast likelihood of long term survival (50% 1yr mortality breast

CA vs no comorbidity affecting long term survival)CA vs no comorbidity affecting long term survival)

• fixed factors in the scenariosfixed factors in the scenarios– socioeconomic statussocioeconomic status– premorbid physical and emotional functionpremorbid physical and emotional function– sex and employmentsex and employment

Comparison of patient and Comparison of patient and physician valuesphysician values

• to anticoagulate or not to anticoagulate to anticoagulate or not to anticoagulate patients with atrial fibrillation: differences patients with atrial fibrillation: differences between physician and patient perspectivesbetween physician and patient perspectives– Devereaux PJ et. al., BMJ, 2001Devereaux PJ et. al., BMJ, 2001

• face to face interview of 63 physicians and face to face interview of 63 physicians and 61 patients61 patients

• probability trade-off tool to determine and probability trade-off tool to determine and compare physician and patient thresholds for compare physician and patient thresholds for how much stroke reduction is necessary and how much stroke reduction is necessary and how much bleeding risk is acceptable for how much bleeding risk is acceptable for antithrombotic therapy in atrial fibrillationantithrombotic therapy in atrial fibrillation

Devereaux et. al., 2001Devereaux et. al., 2001• patients with to atrial fibrillation at high risk of strokepatients with to atrial fibrillation at high risk of stroke

• warfarin decreases risk at cost of increased gi bleedswarfarin decreases risk at cost of increased gi bleeds

• without treatment 100 patients will suffer:without treatment 100 patients will suffer:– 12 strokes (six major, six minor), 3 serious gi bleeds in 2 12 strokes (six major, six minor), 3 serious gi bleeds in 2

yearsyears

• warfarin would decrease strokes in 100 patients to 4 warfarin would decrease strokes in 100 patients to 4 per 2 years (8 fewer strokes, 4 major, minor)per 2 years (8 fewer strokes, 4 major, minor)

• how many bleeds would you accept in 100 patients how many bleeds would you accept in 100 patients over a year, and still be willing to administer/take over a year, and still be willing to administer/take warfarin?warfarin?

STROKES CAN BE MINOR OR MAJOR IN SEVERITY

MINOR STROKE MAJOR STROKE PHYSICAL SYMPTOMS

MENTALSYMPTOMS

PAIN

RECOVERY

FURTHER RISK

IF YOU HAVE A STROKE, YOUR CHANCE OF HAVING A MINOR OR MAJOR STROKE ARE EQUAL

- You suddenly cannot move or feel one arm and one leg

- You are unable to fully understand what is being said to you- You have difficulty expressing yourself

- You feel no physical pain

-You are admitted to hospital-Your weakness, numbness and problem with understanding improve but you still feel slightly weak or numb in one arm and one leg-You are able to do almost all the activities you previously did before the stroke-You can function independently-You leave the hospital after one week

- You have an increased risk of having more strokes

- You suddenly are dizzy and blackout- You are unable to move one arm and one leg- You cannot swallow or control bladder and bowel

- You are unable to understand what is being said- You are unable to talk

- You feel no physical pain

-You are admitted to hospital-You cannot dress-The nurse feeds you-You cannot walk-After 1 month with physiotherapy, you are able to wiggle your toes and lift your arm off the bed-You remain this way for the rest of your life

- Another illness will likely cause your death

SEVERE BLEEDING

AN EXAMPLE OF THIS IS A STOMACH BLEED

PHYSICAL

TREATMENT

RECOVERY

- You feel unwell for two days then suddenly you vomit blood

-You are admitted to hospital-You stop taking warfarin-A doctor puts a tube down your throat to see where you are bleeding from-You receive sedation to ease the discomfort of the test-You do not need an operation-You receive blood transfusions to replace the blood you lost

-You stay in hospital one week-You feel well at the end of your hospital stay-You need to take pills for the next six months to prevent further bleeding-You do not take warfarin any more-After that you are back to normal

Devereaux et. al., 2001Devereaux et. al., 2001• patients with to atrial fibrillation at high risk of strokepatients with to atrial fibrillation at high risk of stroke

• warfarin decreases risk at cost of increased gi bleedswarfarin decreases risk at cost of increased gi bleeds

• without treatment 100 patients will suffer:without treatment 100 patients will suffer:– 12 strokes (six major, six minor), 3 serious gi bleeds in 2 12 strokes (six major, six minor), 3 serious gi bleeds in 2

yearsyears

• warfarin would decrease strokes in 100 patients to 4 warfarin would decrease strokes in 100 patients to 4 per 2 years (8 fewer strokes, 4 major, minor)per 2 years (8 fewer strokes, 4 major, minor)

• how many bleeds would you accept in 100 patients how many bleeds would you accept in 100 patients over a year, and still be willing to administer/take over a year, and still be willing to administer/take warfarin?warfarin?

0

5

10

15

20

25

30

35

40

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22

MAXIMUM NUMBER OF ACCEPTABLE EXCESS BLEEDS

NU

MB

ER O

F PH

YSIC

IAN

S/PA

TIEN

TS

Physicians N=63

Patients N=61

PHYSICIAN AND PATIENT BLEEDING THRESHOLDS FOR WARFARIN

Is this real?Is this real?• retrospective review through record linkage across retrospective review through record linkage across

population based databases in Canadapopulation based databases in Canada• 530 MDs cared for:530 MDs cared for:

– 3120 afib patients with warfarin bleed (intracraneal or 3120 afib patients with warfarin bleed (intracraneal or GI)GI)

– for a patient with afib 90 days prior to bleedfor a patient with afib 90 days prior to bleed– for a patient with afib 90 days after the eventfor a patient with afib 90 days after the event– (some of these MDs also cared for patients up 1 y post)(some of these MDs also cared for patients up 1 y post)– 90% of patients were at high risk for afib-related stroke90% of patients were at high risk for afib-related stroke

• how likely are patients seen how likely are patients seen afterafter an afib patient bled an afib patient bled while on warfarin to receive a warfarin prescription while on warfarin to receive a warfarin prescription (compared to those seen 90 days (compared to those seen 90 days beforebefore the bleed)? the bleed)?

Likelihood of warfarin prescriptionLikelihood of warfarin prescription

1.0

0.79 (0.62-1.00)

0.60 (0.46-0.69)

0.61 (0.46-0.81)

0.72 (0.54-0.97)

1.00 90 d prior

0-90 d post

91-180 d post

181-270 d post

271-360 d post

Odds ratio (95% CI)

Less warfarin after bleeding

Days relative to bleed

ConclusionsConclusions• average patient preferences/values differ from average patient preferences/values differ from

average physician preferencesaverage physician preferences– if physician values determine the decision, patients if physician values determine the decision, patients

won’t get what they wantwon’t get what they want

• physician values/preferences differphysician values/preferences differ– if physician preferences determine decisions, then if physician preferences determine decisions, then

your treatment depends on your physicianyour treatment depends on your physician

• patient values/preferences differpatient values/preferences differ– if use average patient preferences, many patients if use average patient preferences, many patients

won’t get what they wantwon’t get what they want

Values + PreferencesValues + Preferences

Patients’ perspectives, beliefs, Patients’ perspectives, beliefs, expectations, and goals for health and expectations, and goals for health and life.life.Underlying processes used in Underlying processes used in considering the benefits, harms, costs, considering the benefits, harms, costs, and inconveniences patients will and inconveniences patients will experience with each management experience with each management option and the resulting preferences option and the resulting preferences for each option.for each option.

Parental or paternalistic model

Clinician offers minimal information about the options

Clinician deliberates about relative merits of the options

Clinician makes decisions without patient input

NOT CONSISTENT WITH EBM!!!

Clinicians must assess patients values and preferences

Clinicians, acting on their understanding of the patient’s best interest, make a

recommendation

Clinician as perfect agent model

Informed decision making model

Patient receives information about options

Patient deliberates and makes decision with minimal clinician input

Shared decision-making model

Patients and clinicians exchange information about options

They both share information about their V+P

They deliberate together

Reach decision by consensus

Decision making modelsApproaches Parental

Clinician-as-perfect agent

Shared decision-making

Informed

Direction and amount of information flow about options

Clinician Patient

Clinician Patient

Clinician Patient

Clinician Patient

Direction of information flow about values and preferences

Clinician Patient

Clinician Patient

Clinician Patient

Clinician Patient

Deliberation Clinician Clinician Clinician, Patient Patient

Decider Clinician Clinician Clinician, Patient Patient

Consistent with EBM principles

No when decision is not purely technical

Yes Yes Yes

Giving patients what they wantGiving patients what they want• traditional methodstraditional methods

• decision aidsdecision aids– decision boardsdecision boards– decision bookletsdecision booklets– flip chartsflip charts– videosvideos– audiotapesaudiotapes– computerized decision instrumentscomputerized decision instruments

Do decision aids work?Do decision aids work?• systematic review of 34 RCTs

• compared to usual care, decision aids:– increased patient participation in

decision making (RR 1.4, 95% CI: 1.0-2.3)

– improved patient knowledge (19 (95% CI 13-24) points out of 100 in knowledge surveys)

– reduced decisional conflict (9.1 of 100, 95%CI: 6-12)

ConclusionsConclusions• health care provider and patient values influence health care provider and patient values influence

decision making and the two are not always the decision making and the two are not always the samesame

• decision aids decision aids – lead to more certain and informed decisions lead to more certain and informed decisions – increase knowledge about treatment options and increase knowledge about treatment options and

outcomesoutcomes– in some instances lead to decreased preferences for in some instances lead to decreased preferences for

interventions, therapies, and screeninginterventions, therapies, and screening

• what can we do in our own practices?what can we do in our own practices?