Massive cerebral arterial air embolism following arterial catheterization

Cerebral air embolism caused by aspiration pneumonia: A case report

Herein, we report a rare case of arterial cerebral air embolism (aCAE), that was probably caused by aspiration pneumonia. An 84-year-old-male presented with sudden loss of consciousness. Computed tomography (CT) of the head revealed air shadows along the sulcus of the right frontal and left posterior lobes. The abdominothoracic CT revealed aspiration pneumonia in the right upper lung with cavity formation. His clinical symptoms lessened after the administration of an antiepileptic. Because there was no prior history of any medical treatment, the patient was diagnosed with a noniatrogenic aCAE. Furthermore, in the absence of a right-to-left shunt, we determined that the air embolization was caused by the aspiration pneumonia. aCAE is a rare disease that can lead to miserable conditions. Most of causes aCAE are iatrogenic. However, a few cases of noniatrogenic aCAE have been reported. Some reports have suggested an associated between iatrogenic aCAE and raised intrathoracic pressure, which could lead to air entry into the pulmonary vein via the damaged alveolar wall. Even in noniatrogenic aCAEs, a sudden increase in intrathoracic pressure may cause airflow via the alveolar wall into the pulmonary veins, resulting in aCAE.

Investigation of air bubble behaviour after gas embolism events induced in a microfluidic network mimicking microvasculature

Gas embolism is a medical condition that occurs when gas bubbles are present in veins or arteries, decreasing blood flow and potentially reducing oxygen delivery to vital organs, such as the brain. Although usually reported as rare, gas embolism can lead to severe neurological damage or death. However, presently, only limited understanding exists regarding the microscale processes leading to the formation, persistence, movement, and resolution of gas emboli, as modulated by microvasculature geometrical features and blood properties. Because gas embolism is initially a physico-chemical-only process, with biological responses starting later, the opportunity exists to fully study the genesis and evolution of gas emboli using in vitro microfluidic networks mimicking small regions of microvasculature. The microfluidics networks used in this study, which aim to mimic microvasculature geometry, comprise linear channels with T-, or Y-junction air inlets, with 20, 40, and 60 μm widths (arterial or venous), and a 30 μm width honeycombed network (arterial) with three bifurcation angles (30°, 60°, and 90°). Synthetic blood, equivalent to 46% haematocrit concentrations, and water were used to study the modulation of gas embolism-like events by liquid viscosity. Our study shows that (i) longer bubbles with lower velocity occur in narrower channels, e.g., with 20 μm width; (ii) the resistance of air bubbles to the flow increases with the higher haematocrit concentration; and lastly (iii) the propensity of gas embolism-like events in honeycomb architectures increases for more acute, e.g., 30°, bifurcation angles. A dimensionless analysis using Euler, Weber, and capillary numbers demarcated the conditions conducive to gas embolism. This work suggests that in vitro experimentation using microfluidic devices with microvascular tissue-like structures could assist medical guidelines and management in preventing and mitigating the effects of gas embolism.

Venous and arterial air embolism: a rare phenomenon with fatal consequences

Air embolism is often an iatrogenic complication which may occur in venous or arterial circulation depending on the port of entry. We present two cases in which air embolism occurred in venous and arterial circulation after contrast medium injection (CMI) and coronary artery bypass graft (CABG) surgery, respectively. In one case, accumulation of air bubbles was observed in the pulmonary artery after CMI. This was attributed to inadvertent injection of air owing to improper connection of the injector and the catheter. The patient was managed with 100% oxygen in the Trendelenburg and left lateral decubitus position. Repeat imaging demonstrated resorption of the emboli. In another case, air was introduced during CABG in the left atrium and ventricle. Immediate suction of air was attempted however, the patient developed cardiogenic shock requiring vasopressors, and subsequently seizures and coma due to diffuse ischaemic stroke. The patient eventually expired.

Gender Disparity in Failure Rate for Arterial Catheter Attempts

We examined risk factors associated with failure of arterial catheterization in the medical intensive care unit of a large urban teaching hospital. We analyzed 92 consecutive arterial catheterizations by internal medicine house staff and critical care fellows. Of the 92 attempts, 26.1% were done on femoral arteries, and 73.9% were done on radial arteries. Failure, which occurred in 28% of attempts, was more common in female patients ( P < .001). The failure rate was 50.0% for attempts on femoral arteries and 20.6% on radial arteries. Systolic blood pressure was significantly lower in patients where the attempt failed ( P = .024). In univariate analyses, hemoglobin values were lower ( P = .028) and number of percutaneous punctures were higher ( P = .019) in patients where catheterization failed. After multivariate analysis, only gender and systolic blood pressure remained statistically significant. The strongest predictor of failure was female gender. A possible explanation not explored here could be smaller arterial size in female patients.

[A case of cerebral air embolism developed during pleural lavage]

We report a patient with cerebral air embolism in whom we could perform serial brain magnetic resonance images (MRIs). A 78-year-old man was admitted to our hospital because of recurrent empyema after surgery for esophageal cancer. He suddenly demonstrated left hemiparesis in the middle of pleural lavage. After about 30 minutes from onset, the computed tomography (CT) revealed multiple air-isodense spots in the right hemisphere of the brain. After about 2 hours from onset, many hypointense spots in the right hemisphere were revealed on T2*-weighted image (T2*WI). These findings suggested cerebral air embolism. He didn't receive hyperbaric oxygen therapy because he had status epilepticus. The hypointense spots on the T2*WI became smaller and spread after 7 hours from onset and almost disappeared after 53 days. It is important to recognize that cerebral arterial air embolism is similar to multiple microbleeds and cerebral arteriovenous fistula in hypointense spots on the T2*WI.

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.

Predominant vasogenic edema in a patient with fatal cerebral air embolism

Cerebral air embolism (CAE) is a rare neurologic complication that can occur in patients undergoing various medical procedures or trauma. CAE can sometimes result in death caused by severe brain edema. In spite of these implications, the pathophysiologic mechanisms and radiologic features of fatal CAE remain to be elucidated. In this case report, a patient with carcinomatous pleuritis lost consciousness and developed quadriplegia and had generalized seizures during intrathoracic lavage. Serial computed tomography (CT) revealed the presence of air in intracranial blood vessels following severe brain edema; these are typically observed on the CT scans of patients with fatal CAE. Diffusion-weighted imaging (DWI) of the brain obtained at 24 hours after the onset of CAE revealed scattered cortical gyriform high signal intensity often observed in CAE cases, whereas the apparent diffusion coefficient and T2-weighted imaging revealed diffuse hyperintensity in the subcortical deep white matter, indicating vasogenic edema. Our case showed predominant vasogenic edema rather than cortical ischemic changes in the subcortical deep white matter area. These findings indicate that diffuse subcortical vasogenic edema could be the main cause of mortality in fatal CAE.

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.

Cerebral arterial air embolism in a child after intraosseous infusion

Cerebral arterial air embolism (CAAE) has been reported as a rare complication of medical intervention. There has been one reported case of CAAE after the use of an intraosseous infusion (IO) system. We report on a case of CAAE after tibial IO infusion in a 7-month-old girl during resuscitation.

Accidental cerebral venous gas embolism in a young patient with congenital heart disease

This article describes an 11-year-old girl with a diagnosis of Ebstein's anomaly. Glenn and Fontan surgeries were performed successfully. She had a generalized tonic-clonic seizure after peripheral intravenous infusion under pressure. A computed tomography brain scan performed 30 minutes later showed multiple serpiginous hypodensities in the cortical sulci and in the superior longitudinal sinus compatible with cerebral venous gas embolism. At follow-up 1 month later, the girl had severe motor impairment. Cerebral gas embolism should be considered in a patient with risk factors and acute neurological symptoms in order to select the treatment of choice, hyperbaric oxygen, and reduce damage to brain tissues.

Cerebral Gas Embolism Caused by Pleural Fibrinolytic Treatment

Background and Purpose— Intrapleural fibrinolytic therapy is a technique used to treat empyemas and parapneumonic effusions. Cerebral air embolism is an unusual potentially severe complication of this technique.

Summary of Case— A patient with parapneumonic pleural effusion underwent pleural lavage with streptokinase when he suddenly demonstrated focal neurological signs and seizures. The CT revealed multiple air-isodense spots in right hemisphere of the brain, suggesting cerebral air embolism. As a result of early diagnosis and emergency hyperbaric oxygenation, the patient recovered without delayed sequelae.

Conclusions— Air embolism is a potentially severe complication which can occur during fibrinolytic pleural lavage, and clinicians should be aware of this risk. In this context, the onset of acute focal neurological signs or seizures should suggest the possibility of air embolism and lead to the transfer of the patient close to a hyperbaric facility within a few hours.