CONTENTS
general risk stratification
perioperative management of specific medications
perioperative optimization for common disorders
- Cardiac
- Pulmonary
- Cirrhosis
- Renal insufficiency
- Anemia
- Endocrine
Hospitalists or intensivists may be asked to perform preoperative risk assessment for patients admitted to the hospital prior to surgery. Such procedures are nearly always urgent or emergent. The patients involved usually have comorbidities (otherwise we wouldn't be asked for preoperative risk assessment).
This process is sometimes incorrectly referred to as “clearance” for surgery. Preoperative evaluation does include risk stratification, but ultimately it is up to the patient and the surgical team whether to proceed with the procedure.
In reality, there is usually little doubt about whether surgery will occur. Consequently, the primary value of preoperative evaluation is to optimize the patient prior to the surgery and avoid perioperative complications.
The thoroughness of the preoperative evaluation will depend on the urgency of the surgery. Delaying surgery to allow for a more thorough preoperative evaluation is generally unwise.
history
- Review prior medical history (focus on cardiac & pulmonary disorders).
- Evaluate for active cardiopulmonary symptoms:
- Dyspnea?
- Orthopnea? Edema?
- Paroxysmal nocturnal dyspnea?
- Chest pain?
- Palpitations?
- Syncope?
- History of sleep-disordered breathing? Any treatments for this (e.g., CPAP or BiPAP settings)?
- Hematologic:
- History of unusual bleeding?
- Would the patient accept a blood transfusion?
- Prior surgical history and perioperative complications.
- Accurate, current medication list.
- History of alcohol or substance use? (May lead to withdrawal in the postoperative period.)
- History of thyroid disease?
- Ability to achieve 4 METS? This is roughly equal to:
- Climbing a flight of stairs.
- Walk up a hill.
- Run a short distance.
physical examination with POCUS
- Vital signs.
- Auscultation, focusing on the heart and lungs.
- Cardiovascular POCUS including:
- Volume status?
- LV ejection fraction?
- RV failure and/or pulmonary hypertension?
- Aortic stenosis?
laboratory studies that may be considered
- Electrolytes, magnesium level, and renal function.
- Complete blood count with differential.
- Coagulopathy evaluation as clinically warranted:
- INR for patient on warfarin.
- Anti-Xa level for a patient on oral Xa inhibitors.
- Type & screen for blood transfusion.
- Relevant drug levels (e.g., digoxin, lithium, tacrolimus).
- Pregnancy test as appropriate.
- Troponin – only if there is concern that the patient is having acute coronary syndrome.
- Brain natriuretic peptide level (BNP) might help with volume management for selected patients.
- AHA/ACC Class IIa recommendation: For patients with known cardiovascular disease, age >65 years old, or age >45 with symptoms suggestive of cardiovascular disease who are undergoing elevated-risk surgery, it is reasonable to measure BNP or NT-BNP before surgery to supplement evaluation of perioperative risk. (39316661)
- Liver function tests (if there is clinical concern for cirrhosis).
- TSH (thyroid stimulating hormone) if there is clinical concern for thyroid disease.
ECG
- It is generally helpful for any patient (although a single ECG obviously has limited sensitivity).
- Points of interest include:
- Evidence of prior myocardial infarction (involved in calculating the revised cardiac risk index).
- Evidence of active ischemia.
- Detection of arrhythmia (e.g., atrial fibrillation).
- Detection of conduction disorders. (de Luna 2022)
chest radiograph
- Indications may include:
- Hypoxemia.
- Signs/symptoms of pulmonary disease.
- History of lung disease.
- BMI >40 (AHA/ACC recommendation).
- Age >50 and undergoing upper abdominal, thoracic, or abdominal aortic aneurysm surgery (ACP recommendation).
formal echocardiography
- Echocardiography isn't generally required. However, this may be indicated if history and physical examination raise a concern for cardiac dysfunction.
- Echocardiography may serve various purposes:
- [1] Allow treating physicians to understand and optimize the patient's hemodynamics.
- [2] Serve as a baseline study to help evaluate any future changes in cardiac structure over time.
- [3] Evaluation for critical aortic stenosis.
(noninvasive stress testing)
- Noninvasive stress testing is not appropriate for emergent/urgent surgeries. Cardiovascular risk assessment is based on rapidly available information (discussed in the next section).
- Even for elective procedures, the role of noninvasive stress testing is dubious. If coronary artery disease is found, preoperative revascularization hasn't been shown to reduce perioperative cardiac complications. (39316661)
(3a) aspects of the surgical procedure
urgency of surgery
- Emergent procedure: Life or limb threatened without intervention in <6 hours. There is very little or no time for preoperative clinical evaluation (typically <2 hours).
- Urgent procedure: Life or limb threatened without intervention in <24 hours. There may be ~2-24 hours to perform interventions that could reduce the risk of perioperative complications.
- Time-sensitive procedure: Medically necessary to operate within up to 3 months.
- Elective procedure: May be deferred for up to one year. (AHA/ACC 2024)
risk level of procedure
- Low-risk procedures (<1% risk of cardiovascular death or MI in a month) – generally don't require further preoperative cardiac testing.
- Breast or plastic surgery.
- Cataract surgery.
- Endoscopic procedures.
- Dental procedures.
- Thyroid surgery.
- Gynecologic, minor.
- Urologic, minor (transurethral resection of a bladder tumor, transurethral resection of prostate).
- Orthopedic, minor.
- VATS for minor lung resection.
- Other ambulatory procedures.
- Intermediate-risk procedures (cardiac risk usually 1-5%):
- Carotid endarterectomy.
- Peripheral artery angioplasty.
- Head and neck surgeries.
- Non-major intraperitoneal and intrathoracic surgery, e.g.:
- Splenectomy.
- Cholecystectomy.
- Hiatal hernia repair.
- Non-major intrathoracic surgery.
- Major orthopedic surgery (e.g., hip/spine).
- Major neurologic surgery.
- Major urologic/gynecologic surgery.
- Renal transplant.
- High-risk surgery (cardiac risk usually >5%):
- Vascular surgery (excluding carotid endarterectomy).
- Major intraperitoneal or intrathoracic procedures, e.g.:
- Duodeno-pancreatic surgery.
- Liver resection.
- Liver or lung transplantation.
- Pneumonectomy (VATS or open). (36343344)
(3b) Goldman RCRI (revised cardiac risk index)
scoring: one point for each
- [1] High-risk surgery (see above).
- [2] History of ischemic heart disease:
- History of MI.
- History of positive stress test.
- Current chest pain that is considered due to myocardial ischemia.
- Use of nitroglycerine for anginal chest pain.
- ECG with pathological Q-waves.
- [3] History of heart failure, including:
- Pulmonary edema, bilateral rales, or S3 gallop.
- Paroxysmal nocturnal dyspnea.
- Chest radiograph showing pulmonary congestion.
- [4] History of TIA or stroke.
- [5] Preoperative treatment with insulin.
- [6] Pre-operative creatinine >2 mg/dL (or >177 uM).
interpretation: risk of death/MI/arrest within a month after surgery
- 0-1 is considered low risk: (Gaggin 2021)
- 0 points: 4%.
- 1 point: 6%.
- ≧2 is considered elevated risk:
- 2 points: 10%.
- ≧3 points: 15%.
limitations of RCRI include:
- Doesn't perform well with vascular surgeries, where it may underestimate the risk of MI. (Gaggin 2021, 39316661)
- Unclear how this performs with newer, less invasive surgeries (e.g., laparoscopic procedures). (Gaggin 2021)
(3c) integration and overall approach
active high-risk cardiac conditions
- 🚨 If an active high-risk cardiac condition is present, the non-emergent surgery should be delayed until the condition can be treated.
- [1] Acute coronary syndrome.
- [2] Decompensated heart failure.
- This may include symptomatic, severe valvular disease (including severe aortic stenosis and severe mitral stenosis).
- [3] Significant arrhythmias:
- Symptomatic bradycardia.
- Mobitz II or complete AV block.
- Atrial fibrillation with uncontrolled ventricular rate.
- Ventricular tachycardia.
statins
- If the patient is already on a statin, this should be continued. (Class I, AHA/ACC 2024)
- In statin-naive adult patients who meet the criteria for statin use based on ASCVD history or 10-year risk assessment and are scheduled for surgery, perioperative statin initiation is recommended with the intention of long-term use. (Class I, AHA/ACC 2024)
HTN and perioperative BP management
general comments on antihypertensive agents
- For most patients with hypertension going for elective surgery, it is reasonable to continue medical therapy for hypertension throughout the perioperative period. (Class IIa recommendation AHA 2024)
- Severe hypertension (>180/110) should be controlled preoperatively when possible. (Griffin 2022)
- Mild-moderate hypertension may be best left alone and observed. Anesthesia will usually decrease the patient's blood pressure, so aggressive blood pressure control preoperatively may increase the risk of intraoperative hypotension.
beta-blocker
- In patients on stable doses of beta blockers undergoing surgery, beta-blockers should be continued through the perioperative period as appropriate based on the clinical circumstances. (Level I, AHA/ACC 2024)
- In patients scheduled for elective surgery who have a new indication for chronic beta-blocker therapy, this may be started far enough before surgery (optimally >7 days) to permit assessments of tolerability and drug titration if needed. (Class IIb, AHA/ACC 2024)
- In patients undergoing surgery with no immediate need for beta-blockers, beta-blockers should not be initiated on the day of surgery due to the increased risk of postoperative mortality. (Class III, AHA/ACC 2024)
ACE-i/ARB
- Do not initiate this before surgery.
- Consider holding ACE-i/ARB in the following situations:
- [1] Elevated risk of acute kidney injury.
- [2] Current hypotension or elevated risk of encountering hypotension (e.g., epidural anesthesia). (Gaggin 2021)
- If ACE-i/ARB is a component of guideline-directed medical therapy for HFrEF, it is generally reasonable to continue this in the perioperative period to reduce the risk of worsening heart failure. (Class IIa, AHA 2024)
antiplatelet agents
aspirin
- Aspirin can usually be continued if truly indicated (except for neurosurgery/spinal surgery).
- POISE-2 trial demonstrated that initiating aspirin prophylactically for patients with a high risk of perioperative events was not beneficial. (Gaggin 2021)
P2Y12 inhibitors for patients with coronary stents
- The time it takes for P2Y12 inhibitors to wear off: (Harrisons 21st ed, AHA/ACC 2024)
- Clopidogrel: ~5-7 days.
- Ticagrelor: ~3-5 days.
- Prasugrel: ~7-10 days.
- TEG-platelet mapping may occasionally help determine the level of P2Y12 activity. 📖
- P2Y12 inhibitor can generally be held in the following situations (but aspirin should be continued): (Gaggin 2021, AHA/ACC 2024)
- Percutaneous balloon angioplasty without stenting >2 weeks previously.
- Bare metal stent placed >4 weeks previously.
- Drug-eluting stents placed >3-6 months previously.
- If urgent/emergent surgery is required before these time points, the risks/benefits must be carefully considered. For some procedures, it may be possible to continue DAPT through the procedure.
- In rare situations, a continuous infusion of cangrelor (0.75 ug/kg/min) may be used as bridging therapy.
anticoagulation
For urgent or emergent procedures, acute reversal of anticoagulants may be required. 📖 The following section discusses the approach to time-sensitive and elective procedures.
[1] assess thrombotic risk & bleeding risk
- [1] Thrombotic risk is determined using the table above ☝️.
- [2] Bleeding risk: (AHA/ACC 2024)
- Minimal bleeding risk (30-day risk of major bleeding ~0%): Cataract surgery, minor dental/dermatological procedures.
- Low/moderate bleeding risk (30-day risk of major bleeding <2%): Complex dental, gastrointestinal, breast surgery, and procedures using large-bore needles.
- High bleeding risk (30-day risk of major bleeding >2%): More invasive procedures.
[2] formulate a plan for anticoagulation interruption
- The table below shows reasonable time intervals for holding anticoagulation.
- Heparin bridging: In patients with high thrombotic risk (as defined above) undergoing surgery where interruption of warfarin is required, preoperative bridging with parental heparin can be effective in reducing thromboembolic risk. (Class IIa, AHA/ACC 2024)
- Personalization and therapeutic dose monitoring:
- Consider monitoring the anti-Xa level or INR since individual pharmacokinetics may vary.
- Standard recommendations may require modification in some situations due to abnormal liver and kidney function, thrombocytopenia, uremia, and antiplatelet agents.
heart failure management
- Volume status should be optimized before surgery (especially for slightly decompensated patients).
- SGLT2-i should be held before surgery to reduce the risk of euglycemic DKA. (Class I, AHA/ACC 2024)
- In patients with compensated heart failure, it is reasonable to continue GDMT (excluding SGLT2i) in the perioperative period, unless contraindicated, to reduce the risk of worsening HF. (Class IIa, AHA/ACC 2024) Whether to continue ACEi/ARB is discussed further below.
arrhythmia & pacemaker/ICD management
atrial fibrillation
- Achieve adequate heart rate control (e.g., <110 b/m).
- Replete magnesium level to >2 mg/dL.
- (General principles for managing atrial fibrillation in acute illness: 📖)
heart block or sick sinus syndrome
- If a permanent pacemaker is indicated, implantation before surgery could be ideal.
- For emergent surgery, temporary transvenous pacemaker insertion could be considered.
ICDs & pacemakers
- Basics:
- Electrocautery may cause oversensing (with inhibition of pacemaker output) or inappropriate ICD shocks. This is especially problematic if the surgical field is close to the device.
- Monopolar electrocautery is more problematic than bipolar electrocautery. With monopolar electrocautery, the dispersive electrode should be placed away from the pacemaker to direct the electrical current away from the device.
- Use of magnets:
- Magnets will usually cause a pacemaker to pace asynchronously (VVO mode). Magnets will cause ICDs to withhold defibrillation (but, importantly, magnets will not force the asynchronous pacing of an ICD). (AHA/ACC 2024)
- For transvenous pacemakers, magnets shouldn't be relied upon without preoperative confirmation of their effect on the device. Some devices have programmable magnet responses with effects other than forcing prolonged asynchronous pacing (e.g., asynchronous pacing for only ten seconds). (AHA/ACC 2024)
- Guideline-based algorithms for device management are below:
valvular heart disease
aortic stenosis
- Risk factors for worse outcomes include:
- More severe aortic stenosis.
- Symptomatic aortic stenosis.
- Reduced LV systolic function.
- Pulmonary hypertension.
- Historically, critical aortic stenosis was considered a strong contraindication to surgery. However, more recent data suggest that even major surgery can be performed in patients with critical aortic stenosis without an increase in mortality. (24553722)
- AHA/ACC 2024 guidelines regarding elective surgery recommend the following:
- Patients with severe AS should be evaluated for the need for aortic valve intervention before elective surgery. (Class I).
- In asymptomatic patients with moderate or severe AS and normal LV systolic function, as assessed by echocardiography within the past year, it is reasonable to proceed with elective low-risk surgery. (Class IIa)
- The AHA/ACC 2024 guidelines indicate that severe aortic stenosis should only be considered an acute cardiac condition if it causes decompensated heart failure (discussed above in the overall approach to risk stratification ⚡️).
- Role of balloon valvotomy?
- Balloon valvotomy may rarely be considered as a temporizing procedure before urgent surgery.
- This could be considered for patients with severe, symptomatic aortic stenosis who are at high risk of perioperative decompensation.
- A cardiology consultation should be involved to help weigh the risks versus benefits of this procedure. Data regarding this intervention is conflicting.
mitral stenosis
- General perioperative hemodynamic goals:
- Low-normal heart rate.
- High-normal systemic vascular resistance.
- Adequate preload.
- Maintenance of normal sinus rhythm (if possible).
- In patients with severe mitral stenosis who cannot undergo mitral valve repair before surgery, perioperative invasive hemodynamic monitoring is reasonable to guide management and reduce the risk of cardiovascular complications. (Class IIa, AHA/ACC 2024)
- In patients with severe mitral stenosis who cannot undergo mitral valve intervention before surgery, perioperative heart-rate control (e.g., beta-blockers, calcium channel blockers, ivabradine, digoxin) may be considered to prolong diastolic filling time and decrease perioperative cardiovascular complications. (Class IIb, AHA/ACC 2024)
chronic aortic and mitral regurgitation
- Risk factors for worse outcomes include:
- Exercise limitation or symptoms (e.g., orthopnea, paroxysmal nocturnal dyspnea).
- Reduced LV systolic function.
- Atrial fibrillation.
- Pulmonary hypertension.
- General perioperative hemodynamic goals:
- Avoid increased afterload.
- Avoid bradycardia.
- In asymptomatic patients with moderate or severe MR, normal LV systolic function, and estimated PA systolic pressure <50 mm, it is reasonable to perform elective surgery. (Class IIa, AHA/ACC 2024)
- In asymptomatic patients with moderate or severe aortic regurgitation and LV systolic function >55%, it is reasonable to perform elective surgery. (Class IIa, AHA/ACC 2024)
pulmonary hypertension
- Chronic therapies for pulmonary artery hypertension should be continued. (Class I, AHA/ACC 2024)
- In severe PH, invasive hemodynamic monitoring is reasonable to guide intraoperative and postoperative care (severe PH is defined roughly as mPAP >40 mm, PVR >5 Wood Units, or echocardiographic evidence of significant RV morphological alterations). (Class IIa, AHA/ACC 2024)
- In patients with precapillary PH undergoing elevated-risk surgery, perioperative administration of short-acting inhaled pulmonary vasodilators (e.g., nitric oxide or epoprostenol) may be reasonable to reduce elevated RV afterload and prevent acute decompensated right ventricular failure. (Class IIb, AHA/ACC 2024)
pulmonary risk stratification & general pulmonary optimization
pulmonary risk stratification
- ARISCAT score may be utilized: 🧮
risk management
- Consider scheduled bronchodilators for asthma/COPD.
- Treat an exacerbation of respiratory disease if present.
- Early mobilization.
- Avoidance of opioids as able with multimodal analgesia.
OSA/OHS & morbid obesity
management of sleep-disordered breathing
- Ensure that positive airway pressure is utilized postoperatively and at night.
- Avoid excessive use of sedatives or opioids; maximize non-opioid analgesics.
- Use aggressive physical therapy to avoid lung derecruitment.
morbid obesity
- This is a risk factor for venous thromboembolic disease.
- Ensure that DVT prophylaxis is dosed appropriately based on the patient's weight. 📖
cirrhosis
evaluation of risk
- Risk relates strongly to the MELD score:
- Mayo Clinic has a risk score that predicts mortality in patients with cirrhosis: 🧮
complications & management
- Surgery may lead to acute on chronic liver failure, with various organ failures (e.g., hepatic encephalopathy, hepatorenal syndrome, wound dehiscence).
- Preventative strategies may include:
- Avoidance of constipation using PRN lactulose.
- Avoidance of nephrotoxins.
- Optimization of nutritional status.
- Avoidance of deliriogenic medications.
- If cirrhosis-related complications do occur, management is similar to the treatment of other patients with acute on chronic liver failure.
renal insufficiency
- Avoid nephrotoxins in the perioperative period (e.g., hold ACEi/ARB, avoid NSAIDs).
- List of nephrotoxic medications: 📖
- Ensure that medications are dosed appropriately based on the patient's GFR.
anemia
iron deficiency anemia
- In patients with iron deficiency anemia, preoperative iron therapy (either oral or intravenous) is reasonable for reducing blood transfusions and improving hemoglobin. (Class IIa, AHA/ACC 2024)
- Intravenous iron may rapidly replete iron stores. Intravenous iron has even been shown to be beneficial when given postoperatively, illustrating that there isn't a specific timeframe before surgery when it becomes “too late” to give intravenous iron.
- Further discussion of the diagnosis and treatment of iron deficiency anemia: 📖
Jehovah witness patients
- An aggressive and proactive strategy should be formulated to avoid blood loss and promote erythrocyte synthesis.
- Further discussion here: 📖
diabetes
type 2 diabetes
- SGLT2 inhibitors should be held 3-4 days before surgery to avoid euglycemic DKA. Therapy should be resumed once patients are clinically stable and eating normally.
- Metformin continuation during the perioperative period is reasonable for maintaining glycemic control. (Class IIa, AHA/ACC 2024) Metformin-induced lactic acidosis risk is minimal among patients with stable renal function (GFR >30 ml/min) and adequate systemic perfusion. (34424186)
- GLP-1 agonists cause gastroparesis, so the American Society of Anesthesiology recommends holding them before surgery (either for >1 week for agents dosed weekly, or for the day of surgery for agents dosed daily).
- If on long-acting insulin, continue at 50-66% of the chronic dose. (Cecils 27th ed.)
- Follow glucose carefully and correct with short-acting insulin.
type 1 diabetes
- Continue home-dose basal insulin at 100% of the chronic dose.
- Consider intravenous dextrose when the patient is NPO (e.g., D5W at 50 ml/hr) with close monitoring of glucose levels. Treat hyperglycemia with short-acting slide-scale insulin as needed. Ongoing administration of IV dextrose plus PRN insulin should prevent the emergence of diabetic ketoacidosis).
- Follow glucose and electrolytes carefully. Avoid ketoacidosis or hypo/hyperglycemia.
adrenal insufficiency (including chronic steroid therapy)
- Adrenal insufficiency includes patients with Addison disease as well as patients on chronic steroid therapy (≧5 mg prednisone/day for >3 weeks).
- Some escalation in steroid administration is reasonable for high-stress surgeries, but the optimal doses are unclear. The recommendations in the figure below are reasonable. (36343344) Following surgery, the patient should be tapered back to their chronic steroid dose.
- (Further discussion of steroid dosing in the context of stress: 📖).
thyroid disease
- Surgery may trigger decompensation of either hypothyroidism or hyperthyroidism.
- Continue home dose of any thyroid medication.
- If patients have significant hypothyroidism or hyperthyroidism, aggressive medical therapy for this should be initiated immediately (ideally prior to surgery):
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Guide to emoji hyperlinks
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- = Link to IBCC section about a drug.
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References
- 31753535 Bierle DM, Raslau D, Regan DW, Sundsted KK, Mauck KF. Preoperative Evaluation Before Noncardiac Surgery. Mayo Clin Proc. 2020 Apr;95(4):807-822. doi: 10.1016/j.mayocp.2019.04.029 [PubMed]
- 34424186 Cohen DA, Ricotta DN, Parikh PD. Things we do for no reason™: Routinely holding metformin in the hospital. J Hosp Med. 2022 Mar;17(3):207-210. doi: 10.12788/jhm.3644 [PubMed]
- 36343344 Modha K, Whinney C. Preoperative Evaluation for Noncardiac Surgery. Ann Intern Med. 2022 Nov;175(11):ITC161-ITC176. doi: 10.7326/AITC202211150 [PubMed]
- 38033089 Joglar JA, Chung MK, Armbruster AL, Benjamin EJ, Chyou JY, Cronin EM, Deswal A, Eckhardt LL, Goldberger ZD, Gopinathannair R, Gorenek B, Hess PL, Hlatky M, Hogan G, Ibeh C, Indik JH, Kido K, Kusumoto F, Link MS, Linta KT, Marcus GM, McCarthy PM, Patel N, Patton KK, Perez MV, Piccini JP, Russo AM, Sanders P, Streur MM, Thomas KL, Times S, Tisdale JE, Valente AM, Van Wagoner DR; Peer Review Committee Members. 2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines. Circulation. 2024 Jan 2;149(1):e1-e156. doi: 10.1161/CIR.0000000000001193 [PubMed]
- 39316661 Thompson A, Fleischmann KE, Smilowitz NR, de Las Fuentes L, Mukherjee D, Aggarwal NR, Ahmad FS, Allen RB, Altin SE, Auerbach A, Berger JS, Chow B, Dakik HA, Eisenstein EL, Gerhard-Herman M, Ghadimi K, Kachulis B, Leclerc J, Lee CS, Macaulay TE, Mates G, Merli GJ, Parwani P, Poole JE, Rich MW, Ruetzler K, Stain SC, Sweitzer B, Talbot AW, Vallabhajosyula S, Whittle J, Williams KA Sr. 2024 AHA/ACC/ACS/ASNC/HRS/SCA/SCCT/SCMR/SVM Guideline for Perioperative Cardiovascular Management for Noncardiac Surgery: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines. Circulation. 2024 Sep 24. doi: 10.1161/CIR.0000000000001285 [PubMed]