B52-43 Acute Pulmonary Air Embolism After Decompressive Colonoscopy

Abstract An air embolism occurs when air enters the venous or arterial circulation, obstructing blood flow, leading to hemodynamic instability or cardiopulmonary arrest. Though rare, air embolism is a potentially fatal complication of endoscopic procedures. This report describes a unique case of pulmonary air embolism following decompressive colonoscopy. A 67-year-old quadriplegic female with a recent C5-C6 anterior cervical discectomy and fusion presented with abdominal distension and shortness of breath. On arrival, she was tachypneic but hemodynamically stable on 6 liters of nasal cannula oxygen. Examination revealed lethargy, diffuse rales, and a distended, tender abdomen. Laboratory tests were unremarkable. Computed tomography (CT) imaging demonstrated pulmonary edema, multifocal atelectasis, and diffuse colonic dilation (cecal diameter 11 cm) consistent with colonic pseudo-obstruction. After failing conservative management, she underwent decompressive colonoscopy. Post-procedure, the patient developed worsening hypoxia, tachypnea, and tachycardia requiring high-flow nasal cannula at 100% FiO2. Repeat CT imaging revealed moderate volume of air within the main pulmonary artery and small air foci in the right ventricle, consistent with pulmonary air embolism (Figure 1). Small areas of pneumomediastinum were also noted. Immediate management included positioning the patient in the left lateral decubitus and Trendelenburg positions with 100% oxygen therapy. She improved rapidly without the need for hyperbaric treatment. Follow-up imaging showed complete resolution of the pulmonary air emboli. Her hospital course was later complicated by mucus plugging requiring tracheostomy placement, after which she was discharged to a long-term acute care facility in stable condition. Pulmonary air embolism is a rare but serious complication of invasive procedures, most often associated with neurosurgical and otolaryngologic interventions. It results from direct communication between an air source and the vasculature under a pressure gradient, allowing air to enter the systemic or pulmonary circulation. Though endoscopic procedures can theoretically introduce air, clinically significant emboli are exceedingly uncommon, with an estimated incidence of 0.57 per 100,000 and only seven documented cases following colonoscopy. With the reported mortality following endoscopy-related air embolism approaching 15%, this case is notable for the absence of cardiopulmonary arrest and full recovery from an acute embolus. Ultimately, prompt recognition and immediate interventions are critical to reducing overall morbidity and mortality. This abstract is funded by: None