What is the procedure for conducting a preoperative (pre-op) examination?

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From the Guidelines

A preoperative examination should involve a comprehensive assessment of a patient before surgery, including a review of medical history, focused physical examination, and appropriate laboratory tests, with the goal of identifying risk factors and optimizing health status, as recommended by the most recent guidelines 1. To conduct a preoperative exam, begin by reviewing the patient's medical history, including previous surgeries, allergies, current medications, and chronic conditions.

  • Perform a focused physical examination, paying special attention to the cardiovascular and respiratory systems.
  • Vital signs including blood pressure, heart rate, respiratory rate, and temperature should be documented.
  • Order appropriate laboratory tests based on the patient's age, comorbidities, and type of surgery, typically including complete blood count, basic metabolic panel, coagulation studies, and electrocardiogram for patients over 40 or with cardiac risk factors, as suggested by previous guidelines 1.
  • For major surgeries or patients with significant comorbidities, additional tests like chest X-rays, echocardiograms, or pulmonary function tests may be necessary.
  • Assess the patient's functional capacity using metrics like metabolic equivalents (METs) to gauge surgical risk, as recommended by the American College of Cardiology and American Heart Association 1.
  • Document the patient's NPO (nothing by mouth) status and provide clear instructions about which medications to continue or discontinue before surgery.
  • Measure the patient's haemoglobin concentration before listing for major elective surgery, and discuss blood transfusion and alternatives with the patient, obtaining their consent according to local protocols, as recommended by the most recent guidelines 1. This thorough preoperative evaluation helps identify potential complications, allows for appropriate risk stratification, and enables the development of a tailored anesthetic plan, ultimately improving surgical outcomes and patient safety.

From the Research

Preoperative Exam Components

  • A thorough preoperative evaluation is mandatory for all patients undergoing any surgical procedure 2
  • The evaluation should include a detailed patient history and physical examination to assess the patient's health and identify any potential risks 3, 4
  • The physical examination should include an assessment of the patient's cardiac, respiratory, and metabolic conditions 4

Laboratory Tests

  • Routine laboratory tests, such as complete blood counts (CBC), may be ordered as part of the preoperative evaluation 5, 6
  • However, the benefits of routine testing for all surgical patients before operation are extremely limited and are not advocated 3
  • Laboratory tests should be ordered on a case-by-case basis, depending on the patient's individual risk factors and medical history 4

Risk Stratification

  • Clinical scores can be used to specify the patient's individual perioperative risk according to their existing comorbidities 4
  • Risk stratification can help identify patients who require more extensive evaluation and optimization of their medical conditions before surgery 4
  • Strategies to improve the patient's preoperative medical status can help reduce complications in the postoperative period 4

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Preoperative evaluation of the surgical patient.

Dental clinics of North America, 2012

Research

Role of history and physical examination in preoperative evaluation.

European journal of anaesthesiology, 2003

Research

[Preoperative Assessment and Improvement of Patient's Medical Conditions].

Anasthesiologie, Intensivmedizin, Notfallmedizin, Schmerztherapie : AINS, 2022

Research

The complete blood count: physiologic basis and clinical usage.

The Journal of perinatal & neonatal nursing, 1997

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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