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Preoperative management

Last updated: November 3, 2023

Summarytoggle arrow icon

The purpose of a preoperative evaluation is to assess whether a patient is medically optimized for the stress of surgery and to identify reversible factors that may increase the perioperative risk for the patient. Important components of the preoperative evaluation are a thorough history and physical examination, identification of patients at greatest risk of a perioperative adverse event, and appropriate diagnostic testing. Preoperative preparation enhances surgical outcomes by improving the patient's functional status, mitigating identified risk factors, and optimizing perioperative medication regimens. This includes optimization of medical treatment, specialty consultation for advanced disease management, patient education on lifestyle modifications, and instruction on day-of-surgery oral intake and medication use. The extent of patient evaluation and preparation varies according to both the proposed surgery and the patient's functional status. Low-risk patients having low-risk surgery seldom need testing or intervention, while patients with a high disease burden having high-risk surgery often require extensive testing, consultation, and possible postponement of surgery. Patients having emergent surgery still require evaluation even though opportunities for management beyond resuscitation are typically limited.

See also “Postoperative management.”

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Overviewtoggle arrow icon

A preoperative evaluation is performed to determine whether a patient is in optimal health for a planned surgical procedure and its extent depends on the urgency of the surgery.

Approach [1][2][3]

The following applies primarily to patients having elective surgery. See “Emergency preoperative evaluation” for patients needing emergency surgery.

Evaluate the procedural risk and the patient's health and functional capacity in order to: decide whether to proceed with surgery without delay, obtain further testing and/or specialist consultation, or consider delaying or canceling the procedure. [1][2]

Multidisciplinary team roles

  • Medical practitioner [1][2]
    • Determines if the patient is medically optimized for the surgical procedure
    • Initiates measures to optimize the patient's health if necessary
    • Alerts the perioperative team to special health concerns and abnormal test results
  • Surgeon
  • Anesthesiologist: chooses the appropriate anesthetic technique based on patient health and procedural requirements

Emergency preoperative evaluation [8][9]

Patients who need emergency surgery often require simultaneous resuscitation and assessment (e.g., via an ABCDE approach).

Preoperative evaluation of a patient having emergency surgery includes assessing the adequacy of ongoing resuscitation. Continuous reassessment of critical organ function (e.g., tissue perfusion, oxygenation, coagulation) may be necessary.

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Evaluating surgical procedural risktoggle arrow icon

Procedures associated with a > 1% risk of a perioperative major adverse event require more intense preoperative evaluation than lower-risk procedures. [10]

Type of surgical procedure

Morbidity and mortality are associated with the duration of surgery, the anatomical site of surgery, the effect of the surgery on organ perfusion during the procedure, and blood loss. [1][11]

Perioperative mortality by type of surgery [12][13]
Risk Examples

Low

(< 1%)

Intermediate

(1–5%)

High

(> 5%)

Urgency of the surgery

The risk of perioperative morbidity and mortality increases as the urgency of the surgery increases and the time available for clinical evaluation and medical intervention decreases. [1][10][14]

  • Emergency surgery
    • Timing: performed as soon as possible due to threat to life or limb.
    • Perioperative mortality: 3.7% at 30 days
  • Urgent surgery
    • Timing: performed within 24–48 hours due to threat to life or limb
    • Perioperative mortality: 2.3% at 30 days
  • Time-sensitive surgery (e.g., oncologic surgeries)
    • Timing: performed within 1–6 weeks to avoid negative outcomes
  • Elective surgery
    • Timing: performed within 12 months
    • Perioperative mortality: 0.4% at 30 days
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Evaluating patient healthtoggle arrow icon

Goals [15]

  • Assess whether current acute and chronic illnesses are being optimally managed.
  • Begin treatment of untreated or undertreated medical conditions.
  • Identify high-risk patients who may benefit from:
    • Advanced diagnostic testing
    • Medical specialist referral
    • Delay in surgery
    • Higher levels of postoperative care, e.g., ICU admission

Red flags on the preoperative clinical evaluation

A complete medical history and thorough physical examination are performed in all patients having a preoperative evaluation. Special attention should be paid to red flags for conditions that may increase perioperative risk.

Preoperative clinical red flags [1][16]
System History Physical findings

General

  • Open wounds or skin breakdown
  • Atypical head and neck anatomy (e.g., micrognathia, radiation-induced scarring)
  • Implanted devices (e.g., automated implantable cardiac device)
Cardiac
Pulmonary
Hematologic
Endocrine
Gastrointestinal
Neurological
  • Cognitive impairment
  • Neurological deficits

Preoperative functional capacity assessment [10][15][17][18]

Limited functional capacity is associated with an increased risk of perioperative morbidity and mortality. Several techniques are available to estimate functional capacity. [1][19]

  • Subjective patient reporting of exercise capacity [10][19][20]
    • Technique: The patient's subjective report of attainable activity is reported in the metabolic equivalents (METs) associated historically with that activity.
      • Activities associated with ≥ 4 METs
        • Climbing a flight of stairs
        • Walking up a hill
        • Performing strenuous household tasks
      • Activities associated with < 4 METs
        • Walking at 2–3 mph
        • Golfing with a cart
        • Slow ballroom dancing
    • Findings: Exercise capacity of < 4 METs is associated with increased risk of perioperative complication
  • Duke Activity Status Index (DASI) [17][20]
    • Description: a validated, self-administered questionnaire that assesses the patient's functional capacity [21]
    • Technique: A 16 item questionnaire completed by the patient results in a score of 0–58
    • Findings: A DASI score ≤ 34 predicts an increased risk of major perioperative adverse events.
  • Cardiopulmonary exercise testing (CPET) [22]
    • Technique: Laboratory measurement of the patient's maximum VO2 during exercise
    • Findings: No clear threshold for increased perioperative risk has been established using CPET data.

A patient who cannot achieve and maintain 4 METs is at an increased risk for perioperative complications. Additional evaluation may be warranted. [10]

A DASI score ≤ 34 consistently predicts an increased risk of major perioperative adverse events. [20]

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Risk stratification toolstoggle arrow icon

Validated risk stratification tools identify which patients may benefit from medical intervention, preoperative diagnostic testing, and/or consultation prior to intermediate or high-risk surgery. The derived scores from these tools also allow quick communication about patient risk between perioperative team members.

The American Society of Anesthesiologists (ASA) classification [15][23]

  • Description: classification based on subjective reporting of the severity of the patient's comorbid disease
  • Clinical application: all perioperative patients
  • Key finding: An ASA status ≥ 3 is associated with ≥ 1% perioperative risk of mortality; the patient may be considered at high risk.

American Society of Anesthesiologists physical status classification system (ASA-PS) [23][24]

ASA status Definition Thirty-day mortality [25]
I
  • Healthy patient
< 0.1%
II < 1%
III 1–2%
IV ∼ 10%
V > 50%
VI

N/A

E
  • Emergency surgery (appended to grades I–IV)

Revised cardiac risk index (RCRI) [26][27]

Revised cardiac risk index (RCRI) [26]
Category Risk factors
Patient-related
Procedure-related
Interpretation

National Surgical Quality Improvement Program (NSQIP) surgical risk calculator [10][28]

  • Description: web-based patient and surgery-specific risk calculator developed by the American College of Surgeons (ACS)
  • Key finding: reports predicted risk for 11 individual perioperative complications, including death and MACE

Myocardial infarction and cardiac arrest (MICA) risk calculator [10][29]

  • Description: calculator using 5 patient-related inputs (including ASA status) and procedure site
  • Key finding: estimated risk of 30-day mortality; greater predictive power than RCRI but requires more time to calculate

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Diagnosistoggle arrow icon

Approach [1][8][16]

Order diagnostic testing based on the combined risk derived from surgical procedural risk evaluation, preoperative clinical evaluation, and preoperative risk stratification tools. Avoid broad, nondirected testing. [2]

Investigations for intermediate- or high-risk surgery

Preoperative testing for intermediate- or high-risk surgery [1][8][16]
Study Indication
Hemoglobin
Platelet count
  • Liver disease
  • Hematologic disorders
Basic metabolic panel

Fasting glucose and hemoglobin A1c

Liver function tests (LFTs)
Coagulation studies
Blood grouping and crossmatching
  • Significant blood loss is anticipated. [31]
Urinalysis
Pregnancy test
  • Women of childbearing age with uncertain pregnancy status
ECG [10]
CXR [10]

If the preoperative evaluation reveals a previously undiagnosed or undertreated medical condition, further investigation and treatment should be initiated prior to elective surgery if possible.

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Cardiac evaluation and managementtoggle arrow icon

Coronary artery disease (CAD)

Management approach for known or suspected CAD [10]

Advanced testing for CAD [10][27][32]

Preoperative stress testing, CT coronary angiography, and coronary angiography in asymptomatic individuals remain controversial. [32][33]

In asymptomatic patients, perform advanced cardiac testing only when results will affect the decision to operate or the perioperative management.

Elective surgery after coronary angioplasty [35][36]

Discontinuation of P2Y12 receptor blockers (and sometimes aspirin) may be required before surgery. In patients with a cardiac stent, the risks of stent thrombosis must be balanced against the risk of bleeding or delaying surgery.

In patients with a coronary stent, discuss holding aspirin perioperatively with the surgeon; discontinuation is often not required.

Other conditions

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Pulmonary evaluation and managementtoggle arrow icon

General principles

Disease-specific interventions

  • Acute respiratory tract infection [2][40][41]
    • An acute infection increases the risk of perioperative pulmonary and airway complications.
    • Consider delaying surgery to treat the infection.
  • Obstructive sleep apnea (OSA) [42][43]
    • Screen all patients for OSA using a validated tool, e.g., STOP-BANG.
    • Evaluate and document CPAP and BIPAP use.
    • Optimize treatment of moderate to severe OSA that is untreated or undertreated. [43]
  • Chronic pulmonary disease (e.g., asthma, COPD) [1][43]
    • Stable pulmonary disease and adequate oxygenation: Further testing is typically not necessary.
    • Unstable pulmonary disease, impaired oxygenation or ventilation: Consider delaying surgery to allow for further assessment and treatment.
  • Advanced COPD [1][44]

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Evaluation and management of other systemstoggle arrow icon

Malnourishment [45][46][47]

Malnutrition is associated with a higher risk of postoperative mortality and morbidity, e.g., infectious complications and ICU admission. Arrange formal dietary assessment for all patients with risk factors or signs of malnutrition on screening. [45][48][49]

Hepatic disorders [1][50][51]

Hematologic disorders [2]

Endocrine disorders

Neurological disorders

Renal disorders

General principles [63][64]

Management of CKD [63][64]

Prevention of postoperative AKI [63][64]

CKD is associated with increased postoperative complications and mortality and is a risk factor for developing postoperative AKI. [63][65]

Connective tissue diseases (CTDs)

General principles [73]

  • The risk of postoperative complications (e.g., cardiovascular, infection, VTE) is increased in patients with:
  • Delay elective surgery when possible until disease control has been optimized.
  • Consider preoperative specialist consultation to assist with assessment and management of perioperative risks, e.g.:
    • Rheumatology
    • Cardiology
    • Pulmonology
    • Anesthesia

Screening for cervical spine instability

Perioperative management of immunosuppressive therapy [73][75]

Both CTDs and the medications used for their treatment can increase the risk of postoperative complications. [76]

Patients with cervical spine instability due to CTDs have an increased risk of injury during endotracheal intubation, e.g., for general anesthesia. [73]

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Preoperative medication managementtoggle arrow icon

Tailor the decision to continue or discontinue medications to the patient's individual risks and benefits, especially for cardiac and CNS drugs. See also “Perioperative management of oral anticoagulants” for further details on VKAs and DOACs.

Perioperative medication management [2]
Medication General recommendation
Cardiac [10]

Beta blockers

Calcium channel blockers

Nitrates

Statins

  • Continue.
ACEIs or ARBs
  • Hold 24 hours before surgery. [77]
Diuretics
Hematologic Antiplatelet agents [10][78]
Anticoagulants [79][80]
Endocrine [81]

Insulin

  • Short-acting (e.g., regular, aspart, lispro): Hold the morning of surgery.
  • Intermediate-acting (e.g., NPH): Give 50% of the usual dose the morning of surgery.
  • Long-acting (e.g., glargine, detemir): Give 60–80% of the usual dose before surgery.
  • Premixed (e.g., NPH/regular human 70/30)
    • Blood glucose > 200 mg/dL: Give 50% of the usual morning dose.
    • Blood glucose ≤ 200 mg/dL: Give 50% of the intermediate or long-acting component.
  • Insulin pump: Continue basal infusion at 60–80% of the usual rate.
Oral antidiabetics
Estrogens, progestins, and androgens
  • Continue.
Corticosteroids
  • Continue.
Thyroid hormones
  • Continue.
CNS

Parkinson medications

Antiepileptics

Psychotropic drugs other than MAOIs

  • Typically continue. [82]
MAOIs [83]
  • Typically discontinue 2–3 weeks prior to surgery after discussion with the prescriber.
NSAIDs [84][85]
Opioids [86][87][88]
Others [89] Conventional DMARDs
  • Continue.
Biologics
  • Hold after discussion with the prescribing service.
Inhalers
  • Continue.
Herbal medications [90]
  • Typically discontinue ∼ 1 week prior to surgery.

Antianginal medications, antiepileptics, statins, antihypertensive drugs (except ACE inhibitors, ARBs, and diuretics), and neuroleptics should be continued on the day of surgery.

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Preoperative preparation measurestoggle arrow icon

Instruct all patients on recommended perioperative medication changes, oral intake on the day of surgery, and lifestyle modifications that may reduce perioperative risk.

Preoperative lifestyle modifications

  • Smoking cessation: Patients should be encouraged to stop smoking, ideally 4–8 weeks or longer before surgery. [91][92]
  • Alcohol use: Chronic alcohol use is associated with numerous perioperative complications. [93]
  • Exercise: Preoperative exercise programs (often called prehabilitation) may improve some surgical outcomes. [97][98]

Fasting

Perioperative antibiotic prophylaxis [100][101]

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Special patient groupstoggle arrow icon

Preoperative management in pregnant individuals [1][102]

Preoperative management in patients with opioid use disorder (OUD) [86][87][88]

Preoperative management in older adults [60][104]

Preoperative assessment (laboratory studies, cardiac testing) is not routinely required before low-risk surgery (e.g., cataract surgery) regardless of the patient's age. [105]

Preoperative management in pediatric patients [106][107]

Preoperative management is generally similar to adults, with some modifications.

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