Pulmonary Evaluation

Pulmonary Pitfalls - Preop Goals & Risks

• Primary Goals of Preoperative Pulmonary Evaluation:
  • Identify patients at increased risk for Postoperative Pulmonary Complications (PPCs).
  • Optimize baseline pulmonary function to minimize PPC occurrence and severity.
• Key Postoperative Pulmonary Complications (PPCs) include:
  • Atelectasis
  • Pneumonia (e.g., hospital-acquired)
  • Respiratory failure (hypoxemic or hypercapnic)
  • Bronchospasm
  • Exacerbation of underlying chronic lung conditions (e.g., COPD, asthma).

⭐ Atelectasis is the most common PPC, typically developing within the first 24-48 hours postoperatively.

Patient Profiling - Spotting Lung Risks

Key factors increase Postoperative Pulmonary Complication (PPC) risk. Identify using patient and procedure characteristics.

• 📌 Key Factors: Age, preoperative SpO₂, recent respiratory infection, preoperative anemia (Hb <10 g/dL), surgical incision site (e.g., upper abdominal/thoracic), surgery duration >2h, emergency procedure.
• Risk Categories: Low (<26 points), Intermediate (26-44 points), High (≥45 points).

⭐ Surgical site is a major determinant of PPC risk, with thoracic and upper abdominal surgeries carrying the highest risk.

Lung Numbers - PFTs & Imaging

⭐ Routine PFTs are NOT recommended before non-cardiothoracic surgery.

• Pulmonary Function Tests (PFTs):
  • Not routine.
  • Indications:
    • Planned lung resection (e.g., lobectomy, pneumonectomy).
    • Unexplained dyspnea/exercise intolerance.
    • Severe known pulmonary disease if results alter management.
  • Key Parameters & Critical Values:
    • FEV1 (Forced Expiratory Volume in 1s): Critical: < 1.5L or < 50% predicted. High risk if FEV1 < 30% predicted.
    • FVC (Forced Vital Capacity).
    • FEV1/FVC ratio: < 0.7 (or < 70%) suggests obstructive pattern.
    • DLCO (Diffusing capacity for CO): Critical: < 40% predicted.
• Chest X-Ray (CXR):
  • Indicated for new/worsening pulmonary symptoms. Not for routine screening.

Condition Care - Managing Lung Woes

• Asthma: Focus on control.
• COPD: Optimize before surgery.
• OSA: Screen: STOP-BANG (📌 Score ≥ 3 high risk). Continue CPAP.
• Acute Respiratory Infections (ARIs): Postpone elective surgery 4-6 weeks.

Prehab Power - Boosting Lung Defenses

• Smoking cessation: Ideally >4-8 weeks preop; any duration helps ↓ Postoperative Pulmonary Complications (PPCs).
• Optimize COPD/Asthma: Ensure use of bronchodilators, consider steroids if indicated.
• Treat active respiratory infections before surgery.
• Patient Education:
  • Deep breathing exercises.
  • Effective coughing techniques.
  • Incentive spirometry.
• Lung Expansion Maneuvers: e.g., CPAP, IPPB if high risk.
• Consider epidural analgesia for thoracic/upper abdominal surgery to improve pain control and facilitate breathing.

⭐ Smoking cessation for at least 4 weeks before surgery significantly reduces PPCs (Postoperative Pulmonary Complications).

High-Yield Points - ⚡ Biggest Takeaways

• Preoperative spirometry for unexplained dyspnea or poorly controlled lung disease before major surgery.
• FEV1 < 1L or <30% predicted signals high risk for Postoperative Pulmonary Complications (PPCs).
• Smoking cessation for ≥4-8 weeks preoperatively significantly ↓ PPCs.
• ASA status (III-V) and surgical site (thoracic, upper abdominal) are key PPC predictors.
• STOP-BANG score ≥3 indicates high risk for Obstructive Sleep Apnea (OSA).
• Optimize Pulmonary Artery Hypertension (PAH) patients preoperatively due to high risk_._