Peri-operative cardiac risk assessment

 

AHA/CCA Approach

 

List:

1.      Define functional capacity

2.      Identify risk factors

3.      Plug into calculator

4.      Decide how to proceed

 

1. Define functional capacity:

METs

·      1: self-care

·      4: one flight of stairs, walk 6km/h

·      4-10: two flights of stairs, heavy housework

·      >10: sports

DASI

·      Self-care

·      Various intensities of ambulation

·      Various intensities of housework

·      Various intensities of recreational activity

Conversion

·      DASI x 0.43 + 9.6 = VO2

·      VO2 / 3.5 = METs

 

2a. Identify patient risk factors:

Global

·      Elderly

·      ASA ++

·      Poor functional status

Specific

·      IHD

·      Heart failure

·      CVD

·      T2DM insulin

·      CKD

·      (AF)

·      (Obesity)

 

2b. Identify surgical risk factors:

Low

·      Day case

·      Endoscopy

·      Superficial

·      Cataracts

·      Breast

Mod

·      Carotid endarterectomy

·      Head and neck

·      Orthopaedic

·      Prostate

High

·      Intraperitoneal

·      Intrathoracic

·      Supra-inguinal vascular

 

3. Calculate risk:

Scoring:

Low risk: <1% MACE

Mod risk: 1-5% MACE

High risk: >5% MACE

RCRI

·      High risk surgery (as above)

·      IHD

·      Heart failure

·      CVD

·      T2DM insulin

·      CKD (creat >180)

MICA

·      Age

·      Functional status

·      ASA

·      Creat

·      Surgery type

NSQIP

·      Complex online tool

·      General inputs: e.g. age, ASA, emergency vs elective

·      Specific inputs: comorbidities

·      General output: complication, death, rehab facility

·      Specific outputs: CVS complication, wound infection, VTE

 

4. Decide how to proceed:

Go ahead if any of:

·      Emergency surgery

·      Low risk

·      Asymptomatic at >4 METs

·      Not for PCI/CAGs

Do Stress TTE if all of:

·      Moderate or high risk

·      Exercise capacity <4 METs or unknown

·      Would be for PCI/CAGs

 

5. Ignore all the above

Problem

·      Peri-op AMIs are almost always type 2 events

·      Prophylactic PCI and CAGs are unhelpful for most patients

·      Prophylactic studies have excluded patient with left main or triple vessel disease

Recommendation

·      Do stress TTE if the patient needs it anyway (e.g. angina FI)

·      Do PCI/CAGs if the patient needs it anyway (e.g. LMCA or TVD)

·      If unsure, discuss with PMU or a cardiologist

 

Canadian Approach

 

NT-proBNP:

Indications

·      >65y

·      45-65y with CVS disease

·      RCRI ≥1

If abnormal BNP
(or can’t get one)

·      ECG in recovery

·      Daily TNI for 48-72 hours

·      Consider HDU or similar

If abnormal TNI

·      Lifelong aspirin

·      Lifelong statin

 

Other recommendations:

Tests

·      No TTE

·      No stress test

·      No angiography

Medications

·      Continue aspirin only if a) recent stent b) for CEA

·      Don’t start a beta blocker soon before surgery

·      Withhold ACEi and ARB on day of surgery

 

 

Feedback welcome at ketaminenightmares@gmail.com