Perioperative Evaluation (Schneider - 10/4/23)

Sorry, there is no recording available for this session. 

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Thank you to our very own Dr. Dave Schneider for an excellent presentation on Perioperative Evaluation. Unfortunately, I forgot to hit "record" on the zoom meeting, so we do not have a recorded version of his presentation. Sorry about that!

My notes:

First off, "clearance for surgery" is not our job!  Our job is to assess each patient's perioperative risks and optimize and manage those risk factors as they head into surgery. Do note that there are gender and race disparities in those who receive surgical interventions (BIPOC patients receive fewer PCI interventions, fewer orthoplasties and have increased mortality when undergoing these procedures).

The new-ish term for perioperative cardiovascular complications is Myocardial Injury after Non-Cardiac Surgery (aka MINS). 5-19% of surgical patients will experience MINS, 84% will be asymptomatic. MINS is associated with increased morbidity and mortality.

The American College of Cardiology (ACC) last updated their Guidelines for Perioperative Cardiovascular Evaluation and Management for patients undergoing non-cardiac surgery in 2014. These old guidelines are available here. The flow diagram is a doozy and the recommendations are confusing: 

In classic Schneider-fashion, Dr. Schneider invented an acronym to summarize their 2014 recommendations. It is called E-A-R-L-I

E: Emergent: if a surgery is emergent--> take patient to the OR and deal with the negative outcomes later

A: ACS: if the patient has s/sx of ACS, manage per guidelines

R: Risk assess --> use any of several tools (e.g. RCRI, NSQUIP calculator, MICA calculator, see below for more info)

L: Limitation of function --> if patient unable to  perform at 4 METs using the Duke Activity Scale, optimize their functional status before proceeding to surgery

I: Impact on decision? --> Yes or No? If the cardiac stress test outcome will change how/when you will proceed with surgery, then go ahead with a stress test. If not, then proceed to the OR.

The European Society of Cardiology (ESC) updated their guidelines on perioperative management more recently in 2022. And their guidelines are much more simple than those of the ACC. They are summarized here by the ACC. In essence, they say: 

Is the surgery. . .

Emergent? -->  Proceed to surgery without delay, cardiac testing is not feasible

Urgent? --> Proceed to surgery without unnecessary delay (using a multidisciplinary team to determine about individualized cardiac testing)

Time-Sensitive? --> Do the surgery ASAP

Their guidelines are summarized in this lovely flow charts. Don't you just love flow charts?

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Should you check a Hemoglobin and Renal function in all patients pre-operatively? The answer is no, but your should check in intermediate and high risk patients. 

Don't forget, for everyone, advise smoking cessation!

There are two risks to consider in evaluating patients: 1) the risk of the surgery itself (e.g. highest risk includes intra-thoracic, vascular) and 2) the risk of the patient

• If the surgery is low risk, no CV assessment needs to be made
• If the surgery is intermediate risk, and the patient is either >65 or with CV risk factors, get an EKG and check functional capacity
• If the surgery is HIGH risk, consider EKG and biomarkers** for patients older than 45, definitely get them for patients >65 or with CV risk factors. If the patient has known CVD, get a cardiology consultation and make a multidisciplinary decision. 

**Note: Biomarkers referred to above include BNP and/or Cardiac Troponin (also in table above). They have been shown to predict MI. Either one is predictive and do not change outcomes. 

There are several risk calculators to help you determine your patient's  risk level:

1) Revised Cardiac Risk Index (RCRI), which Dr. Schneider shortens to DRC4 (diabetes, risky surgery, CAD, CHF, CVD, Cr>2)

2) The NSQUIP calculator

3) Gupta's Perioperative MICA calculator

Each calculator is slightly different and variably useful depending on the patient in front of you. All three of these have been validated and you should get familiar with all of them.

Okay, now for a few pearls:

• There is NO benefit to coronary revascularization before surgery.
• Labs and other tests should only be done pre-operatively if you were going to do them anyway
• Coag testing is usually unnecessary unless patient is on warfarin. Family Hx and PMH are just as predictive of bleeding (e.g. if patient has history of prior bleed, or family member has bleeding problem, patient has higher risk of bleed)
• Only get a pre-op EKG if the patient has known CVD, CV risk factors >65 and they are having an intermediate/high risk surgery
• TTE only needed if patient has known valvular lesion and no TTE in the last year. You may consider if new onset dyspnea or change in status of their HF
• Pre-op CXR is NOT recommended (Choosing Wisely, ACR 2017)

What about medications?

Statins: if a patient is on a statin, continue it (okay to miss a few days due to NPO, etc.). Perioperative initiation is reasonable if someone is getting vascular surgery

Beta blockers: if patient is already on BB, continue them perioperatively (perioperative withdrawal has 4x increased mortality). You may consider decreasing BB dose due to risk of hypotension after surgery. You can consider starting a BB at least one week (up to 28 days) prior to cardiac surgery if high risk patient and high risk surgery. 

Other anti-hypertensives: post-op hypotension is a common problem. Consider holding all BP meds on day of surgery, add them back slowly post-op, ?one at a time

ASA: it is okay to go to the OR on aspirin. Also okay to stop ASA in high bleeding risk patients (e.g. those on DOAC or warfarin as well). Continuing ASA has been shown to be cardioprotective: decreased MI by 56% and decreased composite CV outcomes. There is a non-significant increased bleeding risk if you continue ASA.

What about patients with recent drug eluting stents (DES)? Delay elective surgery for up to 6 months if possible so as not to interrupt DAPT.