Cerebral air embolism during contrast-enhanced CT

Presence of Gyriform Air Predicts Unfavorable Outcome in Venous Catheter-Related Cerebral Air Embolism

BACKGROUND

This study aimed to investigate the clinical predictors of unfavorable prognosis in patients with venous catheter-related cerebral air embolism.

METHODS

An extensive review of English literature was performed to obtain reports on cerebral air embolism published between January 1982 and July 2014 through PubMed, Journal at Ovid, and Web of Science using the Mesh terms and keywords "cerebral air embolism" and "cerebral gas embolism." Reports not fulfilling the diagnosis of cerebral air embolism and iterant articles were excluded. Demographics, clinical manifestations, and imaging findings were recorded. The air distribution on initial brain computed tomography (CT) was recorded as gyriform air (GF), cavernous sinus bubble, venous sinus bubble, and parenchymal and subarachnoid bubble. The enrolled subjects were further divided into favorable and unfavorable outcome groups for analyses.

RESULTS

Of the 33 cases enrolled, 31 had documented follow-up outcomes, including 14 with favorable and 17 with unfavorable prognoses. Patients with unfavorable outcome had older onset age (67.5 ± 15.8 versus 46.7 ± 17.0 years, P < .001), higher frequency of GF on brain CT (58.8% versus 0%, P < .01), initial consciousness disturbance (100% versus 42.9%, P < .001), and hemiparesis (100% versus 42.9%, P < .001), but lower frequency of cardiopulmonary symptoms (5.9% versus 64.3%, P < .01). In patients with central venous catheter-related cerebral air embolism, the retrograde mechanism had a tendency for worse outcomes (43.8% versus 0%, P = .023).

CONCLUSIONS

In patients with venous catheter-related cerebral air embolism, the presence of GF on brain CT imaging, old age, initial conscious disturbance, and hemiparesis may predict unfavorable outcomes.

Fatal massive cerebral air embolism in a lung transplant patient

INTRODUCTION

Massive air embolism has been described in multiple clinical scenarios, especially in critical ill patients who undergo invasive procedures. Nevertheless, air embolism is often unrecognized and a high index of suspicion is required to diagnose this entity. Two previous cases of air embolism in lung transplant patients have been described in the literature; we describe a third case of fatal massive air embolism and cardiovascular collapse in a lung transplant patient.

METHODS

Case report.

RESULTS

A 52-year-old woman who had a left lung transplant 18 months before admission presented with generalized convulsions and altered mental status. Forty-eight hours after admission and treatment of status epilepticus, she became severely hypotensive and her neurological status deteriorated to brain death. An electrocardiogram showed diffuse ST elevations and a non-contrast head computed tomography demonstrated intravascular air and cerebral edema. Inspection of her intravenous lines did not reveal any leakage or possible port of air entry. An autopsy did not reveal a source of air embolism. Although autopsy did not identify a source for air we suspect that the air originated from the transplanted lung.

CONCLUSION

This case underscores the potential severe consequences of air embolism and its systemic manifestations. A high index of suspicion for cerebral air embolism is warranted in lung transplant patients who present with neurological symptoms.

A case report of cerebral air embolism after esophagogastroduodenoscopy: diagnosis and management in the emergency department

BACKGROUND

Esophagogastroduodenoscopy (EGD) is a rare cause of cerebral air embolism (CAE). To our knowledge, there are only eight previously reported such cases in the history of the procedure.

OBJECTIVE

To identify clinical causes of CAE that can present to the emergency department (ED) and to understand the appropriate management of CAE.

CASE REPORT

A 71-year-old man presented with new-onset left-sided hemiparesis and dysarthria 2h after undergoing an outpatient EGD. The patient was diagnosed with CAE in the ED after undergoing a computed tomography scan of the brain without contrast.

CONCLUSION

The diagnosis of CAE is based on a thorough history and obtaining urgent radiographic imaging of the brain. The definitive treatment of CAE involves hyperbaric oxygen.

Paradoxical air embolism successfully treated with hyperbaric oxygen

The use of the central venous catheter may be complicated by air embolism when central venous pressure is subatmospheric and the catheter is open to the surrounding air. Paradoxical air embolus occurs when the gas bubbles are able to traverse a right to left shunt, gaining access to the systemic arterial circulation causing ischemic symptoms in end organs. In this article, a case of a patient with an unknown patent foramen ovale through which air entered the arterial circulation resulting in obtundation and stroke after inadvertent manipulation of a Hickman catheter is presented. The physiology, clinical manifestations, and management strategies are also discussed.