What is involved in a pre-anesthetic checkup?

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: Ask about snoring, apneic episodes, frequent arousals, morning headaches, and daytime somnolence 2
• Allergy history: Document previous anaphylactic reactions, latex allergy (especially in high-risk groups: atopy, spina bifida, multiple surgeries, healthcare workers, fruit allergies), and drug allergies 2
• Cardiovascular and respiratory disease as these are most commonly associated with 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 assessment: Nasopharyngeal characteristics, neck circumference, tonsil size, tongue volume 2
• Pulmonary examination: Auscultation of the lungs 1
• Cardiovascular examination 1
• Musculoskeletal abnormalities: Osteoarthritis, kyphoscoliosis, fixed flexion deformities 2
• Baseline oxygen saturation in patients with suspected sleep-disordered breathing 2

Laboratory Testing Strategy

Routine preoperative tests ordered without specific clinical indication provide minimal value and should be avoided. 1, 4 Order tests only when clinically indicated: 2, 4

Complete Blood Count (CBC)

• Patients with diseases increasing anemia risk 2
• History of anemia 2
• Anticipated significant perioperative blood loss 2
• Consider pre-operative transfusion if Hb <9 g/dL, or Hb <10 g/dL with ischemic heart disease history 2

Electrolytes and Creatinine

• Chronic disease patients 2
• Medications predisposing to electrolyte abnormalities 2

Glucose Testing

• High risk for undiagnosed diabetes 2

Coagulation Studies (PT, aPTT, Platelet Count)

• History of bleeding disorders 2
• Medical conditions predisposing to coagulopathy 2
• Current anticoagulant therapy 2

Electrocardiogram

The ASA guidelines note that routine ECGs show abnormalities in 7.0-42.7% of cases but lead to clinical management changes in only 9.1% of abnormal findings. 1 Order ECGs based on specific clinical indications rather than routinely.

In healthy ASA I-II patients with normal baseline tests, laboratory testing can be performed up to 2 months before surgery without increased 30-day morbidity or mortality. 5 Testing 2-3 months before surgery shows increased risk and should prompt repeat testing. 5

Timing of Pre-Anesthetic Evaluation

The timing depends critically on surgical invasiveness and patient disease severity: 1

High Surgical Invasiveness

• Medical record review, patient interview, and physical examination must be completed prior to the day of surgery regardless of patient health status 1
• 89% of consultants and 75% of ASA members agree on pre-surgical day timing 1

High Disease Severity

• Initial record review, patient interview, and physical examination must be performed prior to the day of surgery regardless of surgical invasiveness 1

Low Disease Severity with Medium/Low Surgical Invasiveness

• Interview and physical exam may be performed on or before the day of surgery 1

Critical Pitfalls to Avoid

Do not rely on routine screening protocols. 4 A thorough clinical assessment identifying specific indications for testing is more valuable than blanket test ordering and eliminates unnecessary cost without compromising safety. 4

Healthy patients (ASA I-II) can safely undergo anesthesia without preoperative laboratory testing when assessed by history and physical examination. 6 In a study of 1,044 such patients with no preoperative labs, there were zero deaths or major perioperative morbidities (95% CI: 0.00-0.35%). 6

Avoid the misconception that tests must be "fresh." 5 In healthy patients, repeating normal laboratory tests within 2 months of surgery provides no safety benefit and wastes resources. 5

Documentation Requirements

Maintain records that: 7

• Confirm pre-anesthetic checks have been completed 7
• Document allergy status in multiple locations 2
• Record cardiac device information and perioperative management plans 2
• Note sickle cell disease diagnosis clearly for all relevant teams 2