How safe is EBUS? Complication rates <1% at experienced centers
EBUS Complication Rates <1% at Experienced Centers
Endobronchial ultrasound (EBUS) -- an ultrasound probe on the tip of a bronchoscope -- allows real-time viewing of tissues beyond the bronchial wall. It enables more accurate and safer needle biopsies of lymph nodes and masses that abut the bronchial wall. EBUS is an exciting new technology because it can spare people from more invasive surgical biopsies, mediastinoscopy for lung cancer staging or other indications, and transthoracic needle biopsies that have a significant risk for pneumothorax.
EBUS has been believed to be quite safe, based on anecdotal reports and case series from early adopters. But as with any invasive procedure or surgery, the true complication rate of EBUS has been difficult to ascertain. Sample sizes of case series are too small to achieve statistical power, and publication bias is inherent to the reporting of surgical and procedural complications: the most experienced and proficient centers are most likely to publish their glowing data, while average practitioners (who might have a higher complication rate) are unlikely even to gather data on complications, or perform enough cases to allow meaningful conclusions.
The ACCP's ACQuIRE registry has begun to remedy that, collecting and analyzing data on 1,317 patients undergoing EBUS at 6 hospitals (all or nearly all were academic centers training fellows). EBUS proved to be quite safe, indeed, with the following reported complications occurring within 24 hours:
Risk of pneumothorax with EBUS alone: 0.2%, or 1 in 500
Risk of pneumothorax when transbronchial biopsy was also done: 2.7%, or 1 in 37.
There were 7 pneumothoraces total; 4 required tube thoracostomy; the others resolved without intervention.
Bleeding requiring intervention: 0.2%, or 1 in 439
Death: one person, from bleeding (1 in 1,317 or 0.08%)
The overall 24-hour complication rate was 1.4%, but it was <1% when transbronchial biopsy was not done.
Later-occurring infections were not recorded as complications of EBUS.
On-site cytology examination (which can provide a diagnosis during the EBUS procedure, allowing its termination) seemed to reduce the clinician's pursuit of riskier transbronchial biopsies: Sites that had on-site cytology did transbronchial biopsies 13% of the time, vs. 19% of the time for sites without on-demand cytology.
Contrary to previous anecdotal reports, needle aspiration of high paratracheal lymph nodes (2R and 2L) was not associated with an increased risk of pneumothorax.
These were experienced centers, but by the same token, inexperienced fellows were involved for >80% of the procedures analyzed. The average pulmonologist doing an occasional EBUS might have better, or worse outcomes -- those data simply aren't captured here. Still, the ACQuIRE registry data should reassuring to proceduralist physicians and helpful in counseling patients about the relative safety of EBUS.
George Eapen et al. Complications, Consequences, and Practice Patterns of Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration:Results of the AQuIRE Registry. Chest. 2013; 143(4):1044-1053.