What preoperative clearance labs or imaging are always required regardless of procedure or patient's health status?

Preoperative Clearance: Required Tests Regardless of Procedure or Patient Health Status

No preoperative tests are universally required for all patients regardless of procedure or health status. Instead, preoperative testing should be based on the patient's clinical history, physical examination findings, perioperative risk assessment, and clinical judgment 1, 2.

Evidence-Based Approach to Preoperative Testing

General Principles

• Preoperative tests should not be ordered routinely for all patients 2
• Tests should be ordered selectively to guide or optimize perioperative management based on specific clinical characteristics 2, 1
• Indiscriminate preoperative testing leads to unnecessary costs and potential harm without improving outcomes 2

Cardiovascular Assessment

• ECG is not required for all patients but should be performed for:
  • Patients with signs or symptoms of cardiovascular disease 1, 2
  • Patients with cardiovascular risk factors undergoing intermediate or high-risk surgery 1, 3
• Patients undergoing low-risk surgery without risk factors do not require ECG 1, 2

Pulmonary Assessment

• Chest radiography should not be performed routinely for asymptomatic, otherwise healthy patients 1, 2
• Chest radiography is indicated only for patients with new or unstable cardiopulmonary signs or symptoms 1, 2

Laboratory Testing

• Complete Blood Count (CBC):

  • Not required for all patients 1, 4
  • Indicated for patients with diseases that increase risk of anemia or when significant perioperative blood loss is anticipated 1, 2

• Coagulation Studies:

  • Not universally required 1, 5
  • Should be reserved for patients taking anticoagulants, those with history of bleeding, or medical conditions predisposing to coagulopathy 1, 2

• Electrolytes and Renal Function:

  • Not required for all patients 1, 2
  • Indicated for patients at risk of electrolyte abnormalities or renal impairment 1, 2

• Glucose Testing:

  • Not universally required 1
  • Consider for patients at high risk of undiagnosed diabetes or when results would change perioperative management 1, 2

• Urinalysis:

  • Not required for all patients 1, 2
  • Indicated for patients undergoing urologic procedures or implantation of foreign material 1, 2

Special Considerations

High-Risk Patients

• Patients with congenital heart disease require more extensive testing including:
  • Systemic arterial oximetry
  • ECG
  • Chest x-ray
  • Transthoracic echocardiography
  • Full blood count
  • Coagulation screen 2

Cataract Surgery

• Patients in their usual state of health undergoing cataract surgery do not require any preoperative testing 2, 1

Common Pitfalls to Avoid

• Ordering "routine" preoperative tests without clinical indication leads to unnecessary costs and potential false positives 2
• Relying solely on age as an indication for testing rather than considering clinical risk factors 2, 1
• Failing to recognize that abnormal test results rarely lead to changes in management when there are no clinical indications 5, 6
• Not considering the low yield of detecting clinically significant abnormalities in asymptomatic patients 5, 4

Evidence Quality Assessment

The highest quality evidence comes from the American Society of Anesthesiologists 2 and American Academy of Family Physicians 1, 2 guidelines, which consistently recommend against routine preoperative testing. These guidelines are based on systematic reviews showing that routine testing in asymptomatic patients rarely impacts outcomes.