Preoperative evaluation (heart, liver, kidney function & medication considerations) Flashcards
(39 cards)
What is the general recommendation for preoperative cardiac testing?
Most patients undergoing non-cardiac surgery do not require extensive preoperative cardiac testing. However, preoperative cardiac evaluation is warranted in patients with active cardiac conditions (e.g., unstable angina, decompensated heart failure, severe valvular disease like symptomatic aortic stenosis or regurgitation, or significant arrhythmias) or in those undergoing high-risk surgery with significant cardiac risk where evaluation will change perioperative management.
Do emergency surgeries require preoperative cardiac testing?
No.
What noncardiac surgeries are considered high-risk for cardiac complications?
Aortic, vascular surgery involving major vessels, intrathoracic surgery, and open intraperitoneal surgery.
What noncardiac surgeries are considered intermediate-risk for cardiac complications?
Head and neck surgery (e.g., thyroidectomy), orthopedic surgery, and prostate surgery.
What noncardiac surgeries are considered low-risk for cardiac complications?
Breast surgery (e.g., lumpectomy, mastectomy), endoscopic procedures, and cataract extraction.
What is used to assess the cardiovascular risk of noncardiac surgery?
Revised Cardiac Risk Index (RCRI). This assessment tool incorporates six key risk factors.
When is additional cardiac testing (e.g., pharmacologic stress test) required before noncardiac surgery?
In patients with an RCRI score >1 who have poor (<4 METs) or unknown functional capacity, and when testing would alter perioperative management.
What is an example of a condition that would alter peri- or postoperative management?
For example, ACS. In ACS, imaging would be required (CTA) following a positive stress test, then may require revascularization, followed by 6 months of antiplatelet therapy. In this case, the recommendation would be to postpone any elective surgery. It is also important to note that pharmacologic-based stress testing is recommended over exercise-based stress testing (eg, treadmill with echocardiography) because these patients are less likely to achieve an exercise workload adequate for diagnosis.
What are the six risk predictors of the Revised Cardiac Risk Index (RCRI)?
1) High-risk surgery (vascular, intrathoracic)
2) Ischemic heart disease
3) History of congestive heart failure
4) History of cerebrovascular disease (stroke/TIA)
5) Diabetes mellitus treated with insulin
6) Preoperative creatinine >2 mg/dL
How is the risk of major cardiac complications classified based on RCRI score?
0-1 risk factor: low risk (<1%).
≥2 risk factors: elevated risk (>1%).
What is the next step in preoperative evaluation for patients with an RCRI score >1?
Assess functional capacity (≥4 METs) to determine if further cardiac testing is necessary for patients undergoing high risk noncardiac surgeries. If over 4 METs, patients can proceed to surgery.
What is the technical value for 1 MET?
1 MET (metabolic equivalent) = 3.5 mL of oxygen consumed at rest (O2 uptake/kg/min).
What activities correspond to a functional capacity of ≥4 METs?
Climbing a flight of stairs, running a short distance, doing yardwork (raking leaves), participating in golf, tennis, or dancing.
What is the preoperative evaluation pathway for ischemic heart disease in noncardiac surgery?
1) Emergency surgery → Proceed to surgery
2) Acute coronary syndrome → Postpone surgery
3) Low risk (RCRI ≤1 or <1% risk) → Proceed
4) Functional capacity ≥4 METs → Proceed
5) If <4 METs → Cardiac evaluation only if it impacts management
When should elective noncardiac surgery be postponed due to acute coronary syndrome?
If the patient had an acute or recent (<60 days) myocardial infarction or unstable angina, surgery should be delayed for guideline-based management.
When is a preoperative resting echocardiogram indicated?
In patients with heart failure or valvular disease only if there is a change in clinical status (e.g., new dyspnea, worsening murmur).
When is an ECG needed prior to surgery?
- High risk surgeries.
- Underlying cardiovascular risk factors.
What is the role of pharmacologic myocardial perfusion imaging in preoperative evaluation?
Used in high-risk patients with poor (<4 METs) functional capacity only if the results will alter perioperative management (e.g., delaying surgery for revascularization).
When should patient ideally quit smoking before surgery?
4 to 8 weeks before surgery
What considerations need to be made for patients with COPD or asthma or obstructive sleep apnea?
Optimize medication prior to surgery however there is no indication for chest x-ray or pulmonary function test. Inhaled beta agonists (salmeterol) and anticholinergics (ipratropium) reduce the risk of postoperative pulmonary complications in patients with asthma and chronic obstructive pulmonary disease. They should be continued perioperatively.
What is the ideal creatinine prior to surgery?
Less than 2 mg/dL, otherwise associated with increased surgery risk.
what is generally acceptable for liver disease prior to surgery?
Evaluation contingent on the Child-Pugh class or MELD.
What factors determine the Child-Pugh class or MELD?
Specific labs (Bilirubin, INR, PLTs, albumin) and whether a patient has ascites, variceal bleeding, hepatic encephalopathy, jaundice, Hepatorenal syndrome.
What is the hemoglobin level required before surgery?
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