What is the most likely complication of bronchoscopy, particularly in patients with a history of bleeding disorders or those taking anticoagulant medications?

Most Likely Complication of Bronchoscopy

The most likely complication of bronchoscopy is hypoxemia and oxygen desaturation, which occurs commonly during the procedure and drives the risk of cardiac arrhythmias—the most frequently observed significant complication, occurring in up to 40% of patients. 1

Understanding the Complication Hierarchy

While many clinicians focus on dramatic complications like bleeding, the evidence reveals a different reality:

Most Common: Hypoxemia and Cardiac Arrhythmias

• Oxygen desaturation occurs frequently during bronchoscopy and directly correlates with the development of arrhythmias. 1
• Studies demonstrate that 40% of patients develop "significant" arrhythmias during bronchoscopy, with 11% experiencing major but self-limiting arrhythmias. 1
• The risk is particularly elevated during passage of the bronchoscope through the vocal cords. 1
• Hypoxia at the end of the procedure specifically correlates with occurrence of major arrhythmias. 1

Less Common but Serious: Bleeding

• Significant hemorrhage during or after flexible bronchoscopy is actually uncommon, occurring in only 0.7% of routine cases. 1
• When transbronchial biopsies are performed, significant hemorrhage (>50 ml) occurs in 1.6-4.4% of patients. 1, 2
• Bleeding is more likely after transbronchial than endobronchial biopsies, though no deaths were directly attributable to bleeding in large studies. 1

Rare Complications

• Pneumothorax is rare without biopsy, occurring in approximately 4 cases per large series. 3
• Fever occurs in 1.2% after bronchoscopy without lavage, but increases to 10-30% after bronchoalveolar lavage. 1
• Overall severe complication rate across all bronchoscopic procedures is 0.637-0.85%, with mortality at 0.01-0.013%. 3, 4

Special Considerations for High-Risk Patients

Patients with Bleeding Disorders or on Anticoagulants

For patients with bleeding disorders or taking anticoagulants, bleeding risk remains relatively low for diagnostic bronchoscopy without biopsy, but increases substantially when biopsies are performed. 1, 5

High-risk bleeding patients include those with:

• Uraemia, immunosuppression, pulmonary hypertension 1, 2
• Liver disease, coagulation disorders, thrombocytopenia 1, 2
• Patients on oral anticoagulants 1, 2

Management approach:

• Routine preoperative coagulation screening is NOT justified in patients with no risk factors. 1
• In high-risk patients, check platelet count, prothrombin time, and partial thromboplastin time before bronchoscopy. 1, 2
• If biopsy is anticipated, oral anticoagulants should be stopped at least 3 days before bronchoscopy. 2
• If anticoagulation must continue, INR should be reduced to <2.5. 2

Patients with Cardiac Disease

Severe cardiac disease is not an absolute contraindication, but these patients face the highest risk of the most common complication—arrhythmias. 2

Protective measures include:

• Oxygen supplementation to achieve saturation ≥90% reduces arrhythmia risk. 1, 2
• ECG monitoring should be considered in patients with severe cardiac disease or hypoxia despite oxygen supplementation. 1, 2
• Avoid bronchoscopy within 6 weeks of myocardial infarction due to increased arrhythmia risk. 2

Critical Pitfalls to Avoid

• Do not assume bleeding is the most common complication—hypoxemia and arrhythmias occur far more frequently. 1
• Do not skip oxygen supplementation—this is the primary intervention to prevent the most common complication. 1, 2
• Do not routinely check coagulation studies in all patients—only those with specific risk factors require this. 1
• Do not sedate patients with elevated baseline CO₂—this can precipitate respiratory failure. 2