Clinical Controversies in Perioperative Medicine Hugo Quinny Cheng, - - PowerPoint PPT Presentation

Clinical Controversies in Perioperative Medicine

Hugo Quinny Cheng, MD

Division of Hospital Medicine University of California, San Francisco

Predicting & Managing Cardiac Risk

A 70-y.o. man with progressive weakness due to cervical myelopathy will have spinal decompression & fusion. He had a drug-eluting stent placed 8 months ago for stable angina. He also has insulin-requiring diabetes and a remote CVA. He uses a walker, needs help with some ADLs. 1. How do you assess his risk for cardiac complications? 2. What about his drug-eluting stent? 3. Should you start a beta-blocker?

70-y.o. with DES placed 8 months ago, IDDM and remote stroke undergoing cervical spine surgery for weakness. How would you estimate this patient’s cardiac risk?

1. I use the Revised Cardiac Risk Index (RCRI), so ~ 10% 2. I use the RCRI, so ~ 5% 3. I use the “NSQIP” prediction tool, so ~ 1% 4. I don’t need a prediction tool; my gut says he’s high risk

Revised Cardiac Risk Index

Predictors: – Ischemic heart disease – Congestive heart failure – Diabetes requiring insulin – Creatinine > 2 mg/dL – Stroke or TIA – “High Risk” operation

(intraperitoneal, intrathoracic,

• r suprainguinal vascular)

# of RCRI Complications

Predictors All 0.5% 1 1.3% 2 4% ≥ 3 9% All: MI, cardiac arrest, complete heart block, pulmonary edema

Devereaux PJ et al. CMAJ 2005; 173:627.

Serious 0.4% 1% 2.4% 5.4% Serious: MI & cardiac arrest

2007 ACC/AHA Guideline

Good Functional Capacity? Go to OR yes ≥ 3 predictors 1 or 2 predictors no predictors* no or ? Control HR & go to OR (IIa) Vascular surgery? Consider stress test if results will change management (IIa) no yes

• r

(IIb)

Go to OR

* CAD, CHF, DM, CKD, CVA/TIA

New Cardiac Risk Prediction Tool

Derived from National Surgical Quality Improvement Program (NSQIP) database:

• > 400 K patients in derivation & validation cohorts
• Wide range of operations
• “Complication” = 30-day incidence of MI & cardiac arrest

Independent

• 1. Type of surgery

Predictors

• 2. Age
• 3. Serum creatinine > 1.5 mg/dL
• 4. Functional status (dependency for ADLs)
• 5. American Society of Anesth (ASA) class

Gupta PK et al. Circulation 2011; 124:681

ASA Class (a brief digression)

American Society of Anesthesiologists Physical Classification

• 1. Healthy, normal
• 2. Mild systemic disease
• 3. Severe systemic disease
• 4. Severe systemic disease that is a constant threat to life
• 5. Moribund patient not expected to survive without surgery
• Subjective assessment
• Moderate inter-observer variability

NSQIP Cardiac Risk Calculator

www.qxmd.com/calculate-online/cardiology/gupta-perioperative- cardiac-risk

70-y.o. with h/o remote MI, stroke, IDDM undergoing cervical spine surgery. Needs help with some ADLs.

www.qxmd.com/calculate-online/cardiology/gupta-perioperative- cardiac-risk Age 70 Cr < 1.5 ASA Class 3 Partially dependent Spine surgery

70-y.o. with h/o remote MI, stroke, IDDM undergoing cervical spine surgery for progressive weakness.

www.qxmd.com/calculate-online/cardiology/gupta-perioperative-cardiac-risk

Other findings:

• Excellent performance (AUC = 0.88)
• MI/Cardiac arrest strongly predicts mortality (61% vs. 1%)

Caveats:

• Didn’t look at all possible variables (e.g., TTE, stress test)

0.72%

Which Prediction Tool is Better?

RCRI NSQIP

Sample size ~4000 ~400,000 # of hospitals 1 > 200 Currency of data ’89 −’94 ’07 − ’08 Screen for MI? CK-MB, ECG No

Changes to Practice & Guideline?

• Suspect new ACC/AHA guideline will still use RCRI
• Personal practice: use NSQIP when quantifying risk

70-y.o. with DES placed 8 months ago, IDDM and remote stroke undergoing cervical spine surgery for weakness. What about that stent?

1. Operate now, he can’t wait 2. Operate now only if he can continue antiplatelet therapy 3. Wait until 12 months after stent placement

ACC/AHA Guidelines for PCI

• Avoid PCI if patient may have upcoming surgery

that requires stopping dual antiplatelet therapy

• Delay elective surgery in patients with recent PCI

– Bare metal stent: 1 month – Drug eluting stent: 1 year

Surgical Outcomes After Stenting

Question: How do stent type and time until surgery affect risk of cardiac complications? Study Design: Retrospective cohort analysis

• Over 25,000 pts who had noncardiac surgery between

6 weeks & 2 years after BMS or DES placement

• Identify risk factors for cardiac complications (all-cause

mortality, MI, revascularization)

Hawn MT et al. JAMA. doi:10.1001/jama.2013.278787

Time Since Stent Placement

Time of surgery after PCI didn’t matter after first 6 months

20% 15% 10% 5%

60 120 180 240 300 360 6 months Time between PCI & Surgery Complications BMS DES

Hawn MT et al. JAMA. doi:10.1001/jama.2013.278787

Surgical Outcomes After Stenting

Question: Does holding or continuing antiplatelet drugs affect risk of cardiac complications in patients with stents? Study Design: Case-control study

• 284 patients with stents who had antiplatelet drugs held

for noncardiac surgery matched with patients who had drugs continued Results:

• Holding antiplatelet drugs did not increase risk of cardiac

complications (O.R. for 0.86; 95%CI, 0.57-1.29).

Hawn MT et al. JAMA. doi:10.1001/jama.2013.278787

Guidelines for DES

Guideline Recommendation ACC / AHA

Wait 12 months before elective surgery if it requires stopping dual therapy

ACCP

• Wait 6 months before surgery (strong)
• If < 6 months, continue dual therapy (weak)

ESC

• 6 - 12 months of dual therapy
• Continue ASA in favor of clopidogrel

70-y.o. with DES placed 8 months ago, IDDM and remote stroke undergoing cervical spine surgery for weakness. Would you start a beta-blocker?

1. Yes, I follow the guidelines 2. Maybe, I do this less often now 3. No, I’ve stopped doing this 4. No, I’ve never done this because I don’t trust the Dutch

2009 ACC / AHA Guideline for β-blockers

Definite indications (Class 1):

• Already using β-blocker to treat angina, HTN, arrhythmia

Probable indications (Class 2a):

• Vascular or intermediate-to-high risk surgery patients with

coronary disease, or more than 1 other risk predictor *

Uncertainty (Class 2b):

• Patients undergoing vascular or intermediate risk surgery

without coronary disease but with 1 other predictor * * CAD, CHF, DM, CKD, CVA/TIA

POISE: Treatment Protocol

1st dose Metoprolol XL 100 mg 2nd dose Metoprolol XL 100 mg 3rd & daily dose Metoprolol XL 200 mg 2-4 h OR 0-6 h 12 h

Patients: 8351 pts with s/f major noncardiac surgery

• CAD, CHF, CVA/TIA, CKD, DM, or high-risk surgery
• Not already taking β-blocker

Outcome: 30-day cardiac mortality, nonfatal arrest or MI

Devereaux PJ. Lancet. 2008; 371:1839-1847

POISE: Results

Metoprolol XL:

Reduced cardiac events (mostly nonfatal MI) but Increased risk of stroke & total mortality

Devereaux PJ. Lancet. 2008; 371:1839-1847

DECREASE-IV

Patients: 1066 pts with estimated 1-6% risk of postoperative

cardiac complications, undergoing elective non-CV surgery

Treatment: 1. Bisoprolol 2.5 mg daily started at randomization;

• - dose titrated in hospital by 1.25 - 2.5 mg daily;
• - maximum 10 mg daily;
• - target heart rate = 50-70 with SBP >100
• 2. Fluvastatin XL 80 mg daily
• 3. Bisoprolol + Fluvastatin
• 4. Double placebo
• Drugs started median 34 days prior to surgery

Outcome: 30-day cardiovascular mortality or nonfatal MI

Dunkelgrun, M et al. Ann Surgery, 2009; 249: 921-926.

DECREASE-IV Results

Bisoprolol-treated patients had fewer complications Trend towards benefit with statins No safety issues

* * Cardiac Death or Nonfatal MI

Dunkelgrun, M et al. Ann Surgery, 2009; 249: 921-926.

* P = .002

Investigation of possible breaches of academic integrity

Findings regarding DECREASE IV:

• Data poorly documented
• Inclusion criteria violated
• Outcomes not assessed per protocol

Conclusions:

• Cannot vouch for reliability of findings or validity of

conclusions from this trial

β-blockers: So Now What?

Meta-analysis of secure β-blocker trials

• Reduces perioperative MI (mostly asymptomatic)
• Increase in mortality & strokes

Practice & Guideline Changes?

• Uncertain benefit vs. risk, even in high risk patients
• Avoid fixed dose (non-titrated) perioperative β-blockade
• No good reason to start β-blocker without other indication

Bouri, S et al. Heart 2013;0:1–9. doi:10.1136/heartjnl-2013-304262

Managing Perioperative Anticoagulation

Your orthopedic colleague asks your advice on how to manage anticoagulation in two patients who had hip fractures.

• One has atrial fibrillation due to HTN.
• The other has a mechanical AVR.
• Neither has any other relevant comorbidity
• 1. Heparin bridge for AVR only
• 2. Heparin bridge for AF only
• 3. Heparin bridge for both
• 4. Heparin bridge for neither

Thromboembolic Risks with Atrial Fibrillation

Annual Stroke Risk CHADS-2 Score: 1 point for CHF, HTN, Age>75, DM 2 points for Stroke/TIA Score 0 - 2: < 5% stroke risk / yr Score 3 - 4: 5-10% Score 5 - 6: > 10%

Ansell J. Chest. 2004;126:204S-233S.

Thromboembolic Risks with Mechanical Valves

Annual Incidence

Cannegieter, et al. Circulation, 1994

Effect of Mechanical Valve Location & Design on Thromboembolic Risk

Valve Location:

Aortic RR = 1.0 Mitral RR = 1.8

Valve Design:

Caged Ball RR = 1.0 Tilting Disk RR = 0.7 Bi-leaflet RR = 0.6

Cannegieter, et al. Circulation, 1994

Benefits & Harm of Bridging Perioperative Anticoagulation

Death or disability from thromboembolism averted by bridging Death or disability from perioperative bleeding caused by bridging

Benefits & Risks

Randomized trial in progress Review of cohort studies:

Thrombosis Total Bleeding Serious Bleeding Bridged

1.1% 11% 3.7%

Not Bridged

0.9% 2% 0.9%

Odds Ratio

(95% CI)

0.8

(0.4-1.5)

5.4 (3.0-

9.7)

3.6

(1.5-8.5)

Seigal, D et al. Circulation, 2013; 126:1630

Perioperative Anticoagulation:

2012 ACCP Guidelines (9th Edition)

Atrial Fib. Mechanical Valve Recommendation

CHADS2 = 5-6; recent CVA; rheumatic AF Any MVR; older (caged- ball or tilting disc) AVR; recent CVA Bridge with heparin CHADS2 = 3-4 Bileaflet AVR plus other stroke risk factor(s) ??? CHADS2 = 0-2 Bileaflet AVR without AF or

• ther stroke risk factor

No heparin bridge All recommendations are weak, based on low quality evidence

Are Curbside Consults Safe?

You’re about to leave the hospital when an orthopedic surgeon calls you with “a quick, curbside question” about diabetes management for a “stable” patient.

• 1. I never do curbside consults
• 2. Ask questions to determine

whether curbside is appropriate

• 3. No problem! She’s stable.

Curbside Consults

Studied 47 requests for curbside advice to hospitalist

• Curbside consultant could ask questions ad lib
• Made recommendations without seeing patient or chart
• Different hospitalist performed formal, in-person evaluation

Questions:

• Did curbside consultant obtain accurate information?
• Did advice and management differ?

Burden, M et al. J Hosp Med, 2013; 8:31–3

Curbside vs. Formal Medicine Consult

Compared to formal consultation, how

• ften did curbside evaluation lead to:

Incomplete clinical information 34% Inaccurate clinical information 28% Different recommendations 55% Any difference in management 60% Major difference in management 36%

Burden, M et al. J Hosp Med, 2013; 8:31–3

Thank You

quinny@medicine.ucsf.edu