How do you avoid puncturing the lung during a biopsy of a pulmonary nodule?

Techniques to Avoid Pneumothorax During Pulmonary Nodule Biopsy

To avoid puncturing the lung during a pulmonary nodule biopsy, use CT guidance to plan a direct path to the lesion, perform the procedure during suspended respiration, and employ a coaxial technique to minimize pleural punctures. 1

Pre-Procedure Planning

• Imaging selection: CT is the preferred imaging modality for most lesions not suitable for ultrasound guidance 1
• Ultrasound guidance: Use whenever possible as it is the safest, quickest, and least expensive method 1
• Path planning: Review pre-biopsy CT scan to:
  • Choose entry site that avoids crossing fissures, bullae, and large vessels
  • Estimate correct depth of needle insertion
  • Avoid areas of cavitation or necrosis within the lesion 1

Technical Approach

Needle Insertion Technique

• Position patient prone or supine based on chosen entry site (never seated due to air embolism risk) 1
• Insert needle immediately cephalad to a rib to avoid intercostal vessel puncture 1
• Critical step: Only advance or withdraw the needle during suspended respiration 1
• Most patients find holding breath after submaximal inspiration most comfortable 1
• For lung base lesions, gentle expiration may be more effective 1

Coaxial Technique

• Highly recommended: Use a coaxial technique to allow multiple passes while minimizing pleural punctures 1, 2
• Modified coaxial approach:
  • Begin with smaller gauge needle (e.g., 23G) for initial positioning
  • Once lesion is engaged, place larger needle coaxially
  • Obtain multiple specimens through the outer needle without additional pleural punctures 2

Minimizing Pneumothorax Risk

• Avoid directly anesthetizing the pleura as this increases pneumothorax risk 1
• Limit pleural passes to maximum of two if possible, as three or more significantly increases pneumothorax risk 3
• Consider using 17G needles which may have lower pneumothorax rates than 18G needles 3
• Keep procedure time as short as possible, as longer operation times correlate with increased pneumothorax risk 3

Alternative Approaches

• For central lesions: Consider navigational bronchoscopy which has significantly lower pneumothorax rates (3.3% vs 28.3%) compared to transthoracic needle biopsy 4
• For peripheral lesions 10-30mm: Navigational bronchoscopy offers similar diagnostic accuracy to transthoracic needle biopsy with much lower pneumothorax risk 4

Management of Pneumothorax if it Occurs

• Perform immediate manual aspiration for non-small pneumothorax detected on post-biopsy CT
• This can prevent worsening pneumothorax and avoid chest tube placement in most cases 5
• If amount of aspirated air exceeds 543ml, chest tube insertion is more likely to be required 5

Common Pitfalls to Avoid

• Anesthetizing the pleura directly
• Multiple pleural punctures
• Patient movement during needle advancement
• Crossing fissures or bullae
• Excessive procedure time
• Failure to have patient suspend respiration during needle advancement/withdrawal

By following these techniques, pneumothorax rates can be minimized while maintaining high diagnostic accuracy for pulmonary nodule biopsies.