What is involved in a pre-anesthetic checkup?

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Pre-Anesthetic Checkup Components

A comprehensive pre-anesthetic evaluation must include medical record review, patient interview, focused physical examination (airway, lungs, heart, vital signs), and selective laboratory testing based on clinical indications—not routine screening—with timing determined by surgical invasiveness and patient disease severity. 1

Core Components of the Pre-Anesthetic Assessment

Medical Record Review

The pre-anesthetic evaluation begins with assessment of readily accessible medical records, which should document: 1

  • Current diagnoses and medical conditions affecting anesthetic risk 1
  • All medications including dosing, potential drug interactions, and perioperative adjustments needed 2
  • Alternative therapies and supplements the patient is taking 1
  • Previous anesthetic history, particularly any airway difficulties or adverse reactions 2
  • Cardiac rhythm management devices (pacemakers/ICDs) with device type and pacemaker dependency 2

Patient Interview and History

The interview must specifically screen for: 2

  • Obstructive sleep apnea by asking about snoring, apneic episodes, frequent arousals, morning headaches, and daytime somnolence 2
  • Allergy history including anaphylactic reactions, latex allergy (especially in patients with spina bifida, multiple surgeries, healthcare workers, or fruit allergies to banana/chestnut/avocado), and drug allergies 2
  • Cardiovascular and respiratory disease, which represent the most common sources of increased anesthetic risk 3

Focused Physical Examination

At minimum, the physical examination must include assessment of the airway, lungs, and heart with documentation of vital signs. 1 Specifically evaluate: 1, 2

  • Airway examination (100% consensus among ASA consultants and members for high surgical invasiveness) 1
  • Pulmonary examination including lung auscultation (88% consultants, 85% ASA members agree) 1
  • Cardiovascular examination (81% consultants, 82% ASA members agree) 1
  • Nasopharyngeal characteristics, neck circumference, tonsil size, and tongue volume 2
  • Musculoskeletal abnormalities such as osteoarthritis, kyphoscoliosis, or fixed flexion deformities 2
  • Baseline oxygen saturation if sleep-disordered breathing is suspected 2

Timing of Pre-Anesthetic Evaluation

High Surgical Invasiveness or High Disease Severity

For procedures with high surgical invasiveness OR patients with high severity of disease, perform the complete record review, patient interview, and physical examination prior to the day of surgery. 1 This represents 89% consultant and 75% ASA member consensus. 1

Low Surgical Invasiveness with Low Disease Severity

For patients with low disease severity undergoing procedures with medium or low surgical invasiveness, the initial interview and physical exam may be performed on or before the day of surgery. 1

Laboratory Testing Strategy

Order laboratory tests only when justified by specific clinical indications—routine preoperative screening tests are not recommended. 4 The evidence shows that in healthy ASA I-II patients, no deaths or major perioperative morbidities occurred in over 1,000 patients who underwent anesthesia without any preoperative laboratory testing. 5

Indicated Laboratory Tests

Order tests selectively based on these clinical indications: 2

  • Complete blood count (CBC): For patients with diseases increasing anemia risk, history of anemia, or when significant perioperative blood loss is anticipated 2

    • Pre-operative anemia occurs in approximately 40% of hip fracture patients 2
    • Consider pre-operative transfusion if Hb <9 g/dL, or Hb <10 g/dL with history of ischemic heart disease 2
  • Electrolytes and creatinine: For patients with chronic disease and those taking medications predisposing to electrolyte abnormalities 2

  • Random glucose: For patients at high risk of undiagnosed diabetes 2

  • Coagulation testing (PT, aPTT, platelet count): Reserve for patients with history of bleeding, medical conditions predisposing to coagulopathy, or those taking anticoagulants 2

Timing of Laboratory Tests

In ASA I-II patients with normal results, laboratory blood tests performed up to 2 months before surgery are acceptable and do not require repeat testing. 6 Testing 2-3 months before surgery was associated with slightly increased odds of 30-day morbidity (P=0.002), suggesting this is the outer limit. 6

Electrocardiogram Considerations

Do not order routine ECGs without clinical indication. 1 The evidence shows: 1

  • Routine ECGs were abnormal in 7.0-42.7% of cases but led to clinical management changes in only 9.1% of abnormal findings 1
  • Indicated ECGs (ordered for specific clinical reasons) were abnormal in 4.8-78.8% of cases and led to management changes in 2.0-20.0% of abnormal findings 1

Common Pitfalls to Avoid

Do not order "preop status" or "surgical screening" panels—these are not considered specific clinical indications. 1 A thorough clinical assessment is more important than routine tests and eliminates unnecessary cost without compromising safety. 4

Ensure adequate time for evaluation. The healthcare system must provide pertinent information to the anesthesiologist for appropriate assessment well in advance of the anticipated procedure day for all elective patients. 1

Verify patient identity, correct surgical procedure, and correct surgical site while obtaining informed consent. 2 This is a fundamental safety requirement that must not be overlooked.

Documentation Requirements

Maintain clear documentation of: 7, 2

  • Completion of the pre-anesthetic evaluation 7
  • Allergy status, particularly latex and drug allergies 2
  • Cardiac rhythm management device information and perioperative management plan 2
  • Sickle cell disease diagnosis (if applicable) so relevant teams are aware at all stages 2

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Guideline

Pre-Operative Evaluation and Preparation

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Research

[The preoperative check-up, anesthesiologic aspects].

Therapeutische Umschau. Revue therapeutique, 1989

Research

Preoperative assessment.

Lancet (London, England), 2003

Guideline

Anaesthesia Machine Checking Protocol

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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