Pre-op Evaluation Basics

Learner promise

By the end of this module you should understand, at a beginner level, what an anesthesiologist is assessing before surgery and why - including ASA physical status, common red flags, and the questions anesthesia cares about.

Who this is for: students who want to follow pre-op reasoning. Not for: independently clearing or risk-stratifying patients. This is conceptual orientation under supervision.

Why this matters

Surgeons focus on the operation. We're asking something different: can this particular patient safely tolerate anesthesia and the stress of surgery? Once you start hearing pre-op through that question, you'll be a lot more useful there.

ASA physical status - the concept

The American Society of Anesthesiologists (ASA) physical status classification is a quick shorthand for how sick a patient is, conceptually:

• ASA I - a healthy patient.
• ASA II - mild systemic disease (e.g., well-controlled hypertension).
• ASA III - severe systemic disease that limits activity but is not incapacitating.
• ASA IV - severe disease that is a constant threat to life.
• ASA V - a moribund patient not expected to survive without the operation.
• ASA VI - a declared brain-dead patient for organ donation.

You are learning the concept, not assigning classes independently.

Looking at an airway

Four things get checked on almost every pre-op airway exam:

• Mouth opening - we need room to work.
• Neck extension - it lines up the view.
• Teeth - loose or prominent teeth are both a hazard and a warning.
• The space under the chin - a small jaw leaves less room for the tongue.

The Mallampati score grades how much of the back of the throat is visible when a seated patient opens wide and sticks the tongue out:

• Class I - soft palate, tonsillar pillars, and the whole uvula visible.
• Class II - soft palate and uvula visible; pillars hidden.
• Class III - only the soft palate and the base of the uvula.
• Class IV - only the hard palate.

A higher class means less room and a potentially harder view. No single finding decides anything on its own - they get weighed together, and a patient with several concerning features is one where the team sets up differently: more equipment ready, more help in the room, sometimes a different airway plan.

You are learning to recognize these findings, not to grade airways or make airway plans independently.

Beginner-level red flags anesthesia watches for

• Difficult airway signs - small mouth opening, limited neck movement, large tongue, prior difficult intubation.
• Significant cardiac or pulmonary disease - poor exercise tolerance, recent chest pain, severe COPD.
• Anticoagulation / bleeding risk - blood thinners change the plan.
• NPO status - when the patient last ate or drank. A full stomach raises aspiration risk.
• Allergies - especially to anesthetic agents, latex, or antibiotics.

One-page "questions anesthesia cares about" checklist

• [ ] When did you last eat or drink? (NPO status)
• [ ] Have you or your family had problems with anesthesia before?
• [ ] What medications do you take - including blood thinners?
• [ ] Do you have heart or lung problems? How far can you walk?
• [ ] Any loose teeth, dentures, or jaw/neck issues?
• [ ] Any allergies?

Day-one pro tip

When you watch a pre-op visit, try to guess the anesthetic plan before you hear it - then ask "why this plan and not another?" That one habit teaches more than any chapter.

Reflection prompt

Why does "when did you last eat?" matter so much to an anesthesiologist?

Faculty discussion prompt

Ask your resident: "What single pre-op finding most often changes your anesthetic plan?"

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This module is for general education only. It is not medical advice, clinical credentialing, or permission to perform clinical tasks independently. Follow local institutional policy and the direction of your supervising clinicians.