Cerebral Artery Gas Embolism Following Navigational Bronchoscopy

Systemic arterial gas embolism (SAGE) as a complication of bronchoscopic lung biopsy: a case report and systematic literature review

Background

Systemic arterial gas embolism (SAGE) is a rare yet serious and underrecognized complication of bronchoscopic procedures. A recent case of presumed SAGE after transbronchial needle aspiration prompted a systematic literature review of SAGE after biopsy procedures during flexible bronchoscopy.

Methods

We performed a systematic database search for case reports and case series pertaining to SAGE after bronchoscopic lung biopsy; reports or series involving only bronchoscopic laser therapy or argon plasma coagulation (APC) were excluded. Patient data were extracted directly from published reports.

Results

A total of 29 unique patient reports were assessed for patient demographics, specifics of the procedure, clinical manifestations, diagnostic findings, and clinical outcomes. Cases of SAGE occurred after multiple types of bronchoscopic biopsy and under both positive and negative pressure ventilation. The most common clinical findings were neurologic, followed by cardiac manifestations; temporal patterns included acute onset of cardiac or neurologic emergencies immediately after biopsy, or delayed awakening post-procedure. There was a high mortality rate among cases (28%), with residual neurologic deficits also common (24%).

Discussion

SAGE is an underrecognized but severe adverse effect of bronchoscopic lung biopsy, which often presents with acute coronary or cerebral ischemia or delayed awakening from sedation. It is important for all physicians who perform bronchoscopic biopsies to be aware of the clinical manifestations and therapeutic management of SAGE in order to mitigate morbidity and mortality among patients undergoing these procedures.

Cerebral arterial air embolism after endobronchial electrocautery: a case report and review of the literature

Background

Endobronchial electrocautery is a common and safe therapeutic endoscopic treatment for malignant airway obstruction. Cerebral arterial air embolism (CAAE) is a rare but potentially fatal complication of endobronchial electrocautery.

Case presentation

We present the first case of cerebral arterial air embolism after endobronchial electrocautery. A 56-year-old male with a pulmonary tumour in the right upper lobe received repeated endobronchial electrocautery. During the procedure, he experienced unresponsiveness, hypoxemia and bradycardia, and he developed tetraplegia. Brain computed tomography showed several cerebral arterial air emboli with low-density spots in the right frontal lobe. He received hyperbaric oxygen therapy with almost full recovery, except for residual left-sided weakness.

Conclusions

General physicians should realize that CAAE may be a possible complication of endobronchial electrocautery. Several measures, including avoiding positive pressure, lowering ventilatory pressures if possible, avoiding advancing the bronchoscope to occlude the bronchus and using the non-contact technique, should be used to prevent this devastating complication.

Review of Thoracic Causes of Systemic Arterial Air Embolism on Computed Tomography

Systemic arterial air embolism (SAAE) is a rare but potentially life-threatening condition that may occur when air enters into pulmonary veins or directly into the systemic circulation after pulmonary procedures (biopsy or resection) or penetrating trauma to the lung. While venous air embolism is commonly reported, arterial air embolism is rare. Even a minor injury to the chest along with positive-pressure ventilation can cause SAAE. Small amounts of air may cause neurological or cardiac symptoms depending on the affected arteries, while massive embolism can result in fatal cardiovascular collapse. We discuss the various causes of SAAE, including trauma, computed tomography-guided lung biopsy, and various intervention procedures such as mechanical circulatory support device implantation, coronary catheterization, and atrial fibrillation repair. SAAE diagnosis can be overlooked because its symptoms are not specific, and confirmation of the presence of air in the arterial system is difficult. Although computed tomography is the optimal imaging tool for diagnosis, patient instability and resuscitation often precludes its use. When imaging is performed, awareness of the causes of SAAE allows the radiologist to promptly diagnose the condition and relay findings to the clinicians so that treatment, namely hyperbaric oxygen therapy, may be started promptly.