---
name: conducting-pre-operative-evaluations
language: en
description: Structures pre-surgical risk assessment using ACC/AHA guidelines with cardiac and pulmonary clearance. Use when performing preop evaluations, assessing surgical risk, or providing medical clearance.
tags:
  - process
  - primary-care
  - risk
  - surgical
metadata:
  author: casemark
  practice_areas:
    - Family Medicine
    - Internal Medicine
    - Primary Care
  document_types:
    - Process Documentation
  skill_modes:
    - Process Management
---

# Conducting Pre-Operative Evaluations

Structures pre-surgical risk assessment using ACC/AHA guidelines with cardiac and pulmonary clearance.

## Why This Skill Exists

Pre-operative evaluation by a primary care clinician is the most common consultative role in ambulatory medicine. The 2014 ACC/AHA Guidelines on Perioperative Cardiovascular Evaluation and Management provide the evidence-based framework, yet "medical clearance" is frequently misunderstood—the primary care role is to assess and optimize risk, not to "clear" patients for surgery. Perioperative cardiac events occur in 1-5% of non-cardiac surgeries, and 30-day mortality for major surgery ranges from 1-4% depending on procedure and patient factors.

Common errors include ordering unnecessary cardiac testing in low-risk patients (increasing cost and delaying surgery), failing to assess functional capacity, not adjusting perioperative medications appropriately, and providing vague clearance letters that do not communicate risk. This skill enforces the ACC/AHA stepwise algorithm to produce a structured risk assessment with specific recommendations for perioperative management.

---

## Checkpoint A: Pre-Draft Intake (Mandatory)

1. What is the planned surgical procedure and its surgical risk category (low, elevated)? **Default: [REQUIRED]**
2. What is the urgency (elective, urgent, emergent)? **Default: elective**
3. What is the patient's functional capacity in METs? **Default: assess**
4. Does the patient have known or suspected cardiac disease (CAD, HF, valvular, arrhythmia)? **Default: per history**
5. Does the patient have pulmonary disease (COPD, asthma, OSA)? **Default: per history**
6. What medications is the patient currently taking (anticoagulants, antihypertensives, diabetes meds, inhalers)? **Default: per med list**
7. What is the anticipated anesthesia type (general, regional, local/MAC)? **Default: general**
8. What is the patient's BMI, recent labs (CBC, BMP, coags), and ECG status? **Default: pending**

### Documents to Request

- Surgeon's procedure description with estimated blood loss and duration
- Anesthesia questionnaire if completed
- Recent cardiac testing (ECG, echocardiogram, stress test) if available
- Pulmonary function tests if known pulmonary disease
- Sleep study results if diagnosed OSA
- Current medication list with anticoagulant/antiplatelet details
- Recent labs: CBC, BMP, coagulation studies, A1c if diabetic, LFTs if hepatic concern
- Operative reports from prior surgeries noting anesthetic complications
- Advance directive documentation

---

## Step 1: Surgical Risk Stratification

Classify the procedure per ACC/AHA categories:

| Risk Category | Examples | Estimated Cardiac Risk |
|---|---|---|
| Low risk (<1% MACE) | Cataract, endoscopy, superficial procedures, breast biopsy, ambulatory surgery | <1% |
| Elevated risk (≥1% MACE) | Intraperitoneal, intrathoracic, vascular, orthopedic (hip/knee), head and neck, transplant | 1-5%+ |

For low-risk surgery: proceed without further cardiac testing regardless of patient factors (ACC/AHA Class III recommendation—testing not indicated).

---

## Step 2: Cardiac Risk Assessment (ACC/AHA Stepwise Algorithm)

**Step 2a: Is there an acute coronary syndrome or decompensated HF?**
- If yes: defer elective surgery; cardiology consultation; manage acute condition first

**Step 2b: Estimate surgical risk (Step 1 above)**
- Low risk → proceed to surgery without cardiac testing

**Step 2c: Assess functional capacity**
- ≥4 METs (can climb a flight of stairs, walk 2 blocks on level ground, do heavy housework) → proceed without testing
- <4 METs or unable to assess → proceed to Step 2d

**Step 2d: Calculate RCRI (Revised Cardiac Risk Index / Lee Index)**

| RCRI Factor | Points |
|---|---|
| High-risk surgery (intraperitoneal, intrathoracic, suprainguinal vascular) | 1 |
| History of ischemic heart disease | 1 |
| History of heart failure | 1 |
| History of cerebrovascular disease (stroke/TIA) | 1 |
| Diabetes mellitus on insulin | 1 |
| Creatinine >2.0 mg/dL | 1 |

| RCRI Score | Risk of Major Cardiac Event | Action |
|---|---|---|
| 0 | 3.9% | Proceed; testing unlikely to change management |
| 1 | 6.0% | Proceed; consider testing only if it will change management |
| 2 | 10.1% | Pharmacologic stress test if results will alter management |
| ≥3 | 15%+ | Stress testing recommended; cardiology consultation |

Do NOT order stress testing if the result will not change surgical decision.

---

## Step 3: Pulmonary Risk Assessment

**Assess risk using ARISCAT score or clinical judgment:**

| Risk Factor | Assessment |
|---|---|
| Known COPD/asthma | Ensure optimal inhaler therapy; FEV1 <60% predicted = higher risk |
| Current smoking | Counsel cessation ≥4 weeks before surgery (ideally 8 weeks); NRT permitted perioperatively |
| Obstructive sleep apnea | Document STOP-BANG score; patient must bring CPAP to hospital; inform anesthesia |
| Obesity (BMI ≥40) | Increased atelectasis and DVT risk; may need post-op ICU bed |
| Upper abdominal or thoracic surgery | Highest pulmonary complication risk; incentive spirometry should be ordered |

**Do NOT order routine preoperative PFTs** unless:
- Unexplained dyspnea not adequately characterized
- Known lung disease requiring optimization before thoracic or upper abdominal surgery
- Lung resection planned (need to estimate post-resection pulmonary function)

---

## Step 4: Perioperative Medication Management

| Medication | Recommendation | Rationale |
|---|---|---|
| Beta-blockers (chronic) | CONTINUE through surgery | Abrupt withdrawal → rebound tachycardia, ischemia (POISE trial) |
| Statins | CONTINUE | Pleiotropic perioperative benefit |
| ACEi/ARB | HOLD morning of surgery | Intraoperative hypotension risk; restart when euvolemic |
| Diuretics | HOLD morning of surgery | Hypovolemia risk |
| Aspirin (primary prevention) | HOLD 7 days before surgery | No proven perioperative benefit for primary prevention |
| Aspirin (secondary prevention / stent) | CONTINUE unless high bleeding risk | Discuss with surgeon and cardiologist; bare-metal stent: ≥30 days DAPT; DES: ≥6 months DAPT |
| Warfarin | HOLD 5 days before surgery; bridge only if high thrombotic risk (mechanical valve, recent VTE) | INR target <1.5 for most procedures |
| DOACs | HOLD 24-48 hours before surgery (varies by agent and renal function) | Rivaroxaban/apixaban: 24h for low-risk, 48h for high-risk; dabigatran: 48-72h if CrCl <50 |
| Insulin | Reduce basal by 25-50% night before surgery; hold prandial insulin morning of surgery | Hypoglycemia prevention |
| Metformin | HOLD morning of surgery; restart when eating and renal function stable | Theoretical lactic acidosis risk with contrast/renal insult |
| Sulfonylureas | HOLD morning of surgery | Hypoglycemia risk when NPO |
| Oral contraceptives / HRT | Consider holding 4 weeks before major surgery if high VTE risk | Thrombotic risk |

---

## Step 5: Pre-Operative Assessment Letter

Structure the communication to the surgeon:

1. **Medical conditions relevant to surgical risk** — list with severity and current management
2. **Cardiac risk assessment** — RCRI score, functional capacity, need for further testing
3. **Pulmonary risk** — COPD/OSA status, CPAP requirements, PFT results if obtained
4. **Medication management** — specific hold/continue instructions with dates
5. **Laboratory requirements** — any pending labs needed before surgery date
6. **Optimization recommendations** — items to address before surgery (e.g., smoking cessation, A1c optimization, anemia correction)
7. **Risk statement** — "The patient is at [low/moderate/elevated] perioperative risk based on RCRI and procedure classification. Risk-benefit discussion has been completed."

Do NOT write "cleared for surgery"—this implies a guarantee that no complication will occur and is medically and legally indefensible.

---

## Checkpoint B: Post-Draft Alignment (Mandatory)

1. Is the surgical procedure classified by risk category (low vs. elevated)?
2. Has functional capacity been assessed in METs?
3. Is the RCRI calculated with appropriate cardiac testing recommendation?
4. Are all medication hold/continue instructions specific with timing?
5. Does the assessment letter communicate risk clearly without using the word "cleared"?

---

## Quality Audit

- [ ] Surgical procedure identified with risk category (low vs. elevated)
- [ ] Urgency documented (elective, urgent, emergent)
- [ ] Functional capacity assessed in METs with method documented
- [ ] RCRI calculated with all six factors addressed
- [ ] Cardiac testing ordered only when results would change management
- [ ] Pulmonary risk assessed with OSA, COPD, smoking status documented
- [ ] Medication management table completed with specific hold/continue dates
- [ ] Anticoagulation bridging decision documented with rationale
- [ ] Diabetic medication adjustment plan specified for NPO period
- [ ] Labs ordered as appropriate for procedure and comorbidities (not reflexive panels)
- [ ] Assessment letter structured without the phrase "cleared for surgery"
- [ ] Advance directive status documented or discussion offered
- [ ] Patient informed of perioperative risks relevant to their medical conditions
- [ ] Follow-up plan established for post-surgical medication resumption

---

## Guidelines

- Never order routine pre-operative testing (ECG, CXR, labs) for low-risk surgery in healthy patients—Choosing Wisely recommendation against routine preoperative testing
- Beta-blockers should never be initiated de novo on the day of surgery; the POISE trial showed increased stroke and mortality with perioperative beta-blocker initiation
- "Medical clearance" is not a medical term; the role of the primary care clinician is risk assessment and optimization, not guaranteeing surgical safety
- Asymptomatic carotid bruit does not require preoperative carotid imaging unless the patient has neurologic symptoms
- Pre-operative ECG is reasonable for patients with known cardiac disease, significant risk factors, or elevated-risk surgery, but is NOT indicated for low-risk surgery
- Post-menopausal bleeding, new murmur, or unexplained syncope discovered during preoperative evaluation require diagnostic workup before elective surgery proceeds
- Patients with drug-eluting stents within 6 months require cardiology consultation before stopping dual antiplatelet therapy
- Communicate the assessment to the surgeon, anesthesiologist, and patient—not just the chart