[Cerebral arterial air embolism: the effect of hyperbaric oxygen therapy]. / Cerebrale arteriële luchtembolie.

BACKGROUND: Iatrogenic gas embolism is the presence of gas in vascular structures. Feared are those in coronary or cerebral arteries. These can result in cerebral or myocardial infarction. CASE DESCRIPTION: A 79-year-old female underwent CT-guided biopsy of the lung. Minutes later she developed neurological symptoms. After administration of oxygen her symptoms initially improved, but later worsened. Based on her symptoms air embolism was suspected. She recovered fully after treatment with hyperbaric oxygen. CONCLUSION: Air embolism is a potentially life-threatening complication of surgical, radiological or vascular interventions. Early recognition can lead to prompt treatment and better prognosis. If air embolism is suspected the patient should be treated according to ABCDE principles and oxygen should be administered. In case of neurological or circulatory symptoms a hospital that could provide hyperbaric oxygen therapy should be contacted as soon as possible.

Air embolism during lumbar surgery in the prone position.

Only a few clinical cases of cerebral arterial gas embolism during spinal surgery are published. It seems important not to overlook this diagnosis in order to initiate rapid appropriate treatment. This was a suspected case of paradoxical gas embolism revealed postoperatively by neurological deficits and whose recovery was noted during hyperbaric oxygen treatment. Unfortunately, no complementary examination showed gas embolism and only the context, the clinical picture and the case evolution evoke this diagnosis. The diagnostic difficulty in the immediate postoperative period is highlighted.

Hyperbaric treatment of air or gas embolism: current recommendations.

Gas can enter arteries (arterial gas embolism, AGE) due to alveolar-capillary disruption (caused by pulmonary over-pressurization, e.g. breath-hold ascent by divers) or veins (venous gas embolism, VGE) as a result of tissue bubble formation due to decompression (diving, altitude exposure) or during certain surgical procedures where capillary hydrostatic pressure at the incision site is subatmospheric. Both AGE and VGE can be caused by iatrogenic gas injection. AGE usually produces stroke-like manifestations, such as impaired consciousness, confusion, seizures and focal neurological deficits. Small amounts of VGE are often tolerated due to filtration by pulmonary capillaries; however VGE can cause pulmonary edema, cardiac "vapor lock" and AGE due to transpulmonary passage or right-to-left shunt through a patient foramen ovale. Intravascular gas can cause arterial obstruction or endothelial damage and secondary vasospasm and capillary leak. Vascular gas is frequently not visible with radiographic imaging, which should not be used to exclude the diagnosis of AGE. Isolated VGE usually requires no treatment; AGE treatment is similar to decompression sickness (DCS), with first aid oxygen then hyperbaric oxygen. Although cerebral AGE (CAGE) often causes intracranial hypertension, animal studies have failed to demonstrate a benefit of induced hypocapnia. An evidence based review of adjunctive therapies is presented.

Intracardiac Thrombus Following Rivaroxaban Treatment in a Patient with Atrial Fibrillation Associated with Rheumatic Heart Disease.

We report a case of atrial fibrillation with rheumatic heart disease (RHD) who had intracardiac thrombus and cardiogenic cerebral embolism with rivaroxaban therapy. Intracardiac thrombus disappeared after switching from rivaroxaban to warfarin. Patients of RHD have the possibility of gradual progression of valvular disease even if they are old, so we need to distinguish nonvalvular atrial fibrillation from RHD before starting direct oral anticoagulants.

Predictors of Recurrent Ischemic Stroke in Patients with Embolic Strokes of Undetermined Source and Effects of Rivaroxaban Versus Aspirin According to Risk Status: The NAVIGATE ESUS Trial.

BACKGROUND: Embolic stroke of undetermined source (ESUS) identifies patients with cryptogenic ischemic stroke presumed due to embolism from several unidentified sources. Among patients with recent ESUS, we sought to determine independent predictors of recurrent ischemic stroke during treatment with aspirin or rivaroxaban and to assess the relative effects of these treatments according to risk. METHODS: Exploratory analyses of 7213 participants in the NAVIGATE ESUS international trial who were randomized to aspirin 100 mg/day or rivaroxaban 15 mg/day and followed for a median of 11 months, during which time there were 309 first recurrent ischemic strokes (4.6% per year). Baseline features were correlated with recurrent stroke by multivariate analysis. RESULTS: The 7 independent predictors of recurrent stroke were stroke or transient ischemic attack (TIA) prior to the qualifying stroke (hazard ratio [HR] 2.03 95% confidence internal [CI] 1.58-2.60), current tobacco user (HR 1.62, 95% CI 1.24-2.12), age (HR 1.02 per year increase, 95%CI 1.01-1.03), diabetes (HR 1.28, 95% CI 1.01-1.64), multiple acute infarcts on neuroimaging (HR 1.49, 95% CI 1.09-2.02), aspirin use prior to qualifying stroke (HR 1.34, 95% CI 1.02-1.70), and time from qualifying stroke to randomization (HR .98, 95% CI .97-.99). The rate of recurrent stroke rate was 2.6% per year for participants without any of these risk factors, and increased by an average of 45% for each independent predictor (P < .001). There were no significant interactions between treatment effects and independent stroke predictors or stroke risk status. CONCLUSIONS: In this large cohort of ESUS patients, several features including prior stroke or TIA, advanced age, current tobacco user, multiple acute infarcts on neuroimaging, and diabetes independently identified those with an increased risk of ischemic stroke recurrence. The relative effects of rivaroxaban and aspirin were similar across the spectrum of independent stroke predictors and recurrent stroke risk status.

Early hyperbaric oxygen therapy for cerebral air embolism during atrial fibrillation ablation.

Cerebral air embolism is a potentially life-threatening complication of left-sided ablation procedures. We present a 51-year-old woman with cerebral air embolism during atrial fibrillation cryoballoon ablation. Taking a deep breath while removing the dilatator was the most likely mechanism in our case. The patient was successfully treated with hyperbaric oxygen therapy at early stage and was discharged without any neurological sequelae.

Cerebral lipiodol embolism related to a vascular lake during chemoembolization in hepatocellular carcinoma: A case report and review of the literature.

A male patient underwent conventional transcatheter chemoembolization for advanced recurrent hepatocellular carcinoma (HCC). Even after the injection of 7 mL of lipiodol followed by gelatin sponge particles, the flow of feeding arteries did not slow down. A repeat angiography revealed a newly developed vascular lake draining into systemic veins; however, embolization was continued without taking noticing of the vascular lake. The patient's level of consciousness deteriorated immediately after the procedure, and non-contrast computed tomography revealed pulmonary and cerebral lipiodol embolisms. The patient's level of consciousness gradually improved after 8 wk in intensive care. In this case, a vascular lake emerged during chemoembolization and drained into systemic veins, offering a pathway carrying lipiodol to pulmonary vessels, the most likely cause of this serious complication. We should be aware that vascular lakes in HCC may drain into systemic veins and can cause intratumoral arteriovenous shunts.

A Rare Case of Cerebral Air Embolism Caused by Pulmonary Arteriovenous Malformation After Removal of a Central Venous Catheter.

Cerebral air embolism following central venous catheter (CVC) removal is extremely rare. We report a case of cerebral air embolism with loss of consciousness after removal of CVC caused by pulmonary arteriovenous malformation (PAVM). Computed tomography revealed air bubbles in the internal carotid arteries along the sulci in the cerebral hemispheres, as well as a PAVM. The cerebral air embolism was treated with hyperbaric oxygen and intravenous thrombolytic therapy, and transcatheter embolization of the PAVM was performed. When inserting/removing CVC in a patient with a small PAVM, treatment of the PAVM, irrespective of its size, could prevent the type of complication that occurred in our present case.

Ultradense Middle Cerebral Artery: Specific Sign of Cerebral Lipiodol Embolization.

Cerebral lipiodol embolization is a rare but known complication of lymphatic embolization for plastic bronchitis. The classic imaging finding on a noncontrast head computed tomography is multiple small areas of hyperdensity within the cerebral hemispheres, which represent lipiodol deposition in the brain. We report a case of lipiodol deposition in the middle cerebral artery following lymphatic embolization, producing an "ultradense" vessel sign on noncontrast computed tomography.

Cerebral arterial gas embolism from attempted mechanical thrombectomy: recovery following hyperbaric oxygen therapy.

Cerebral arterial gas embolism is a recognised complication of endovascular intervention with an estimated incidence of 0.08%. Its diagnosis is predominantly clinical, supported by neuroimaging. The treatment relies on alleviating mechanical obstruction and reversing the proinflammatory processes that contribute to tissue ischaemia. Hyperbaric oxygen therapy is an effective treatment and has multiple mechanisms to reverse the pathological processes involved in cerebral arterial gas embolism. Symptomatic cerebral arterial gas embolism is a rare complication of endovascular intervention for acute ischaemic stroke. Although there are no previous descriptions of its successful treatment with hyperbaric oxygen therapy following mechanical thrombectomy, this is likely to become more common as mechanical thrombectomy is increasingly used worldwide to treat acute ischaemic stroke.

Hyperbaric oxygen therapy for cerebral air gas embolism following orthotopic heart transplant: case report.

Air gas embolism (AGE) is a rare complication of cardiac surgery, with high morbidity and mortality. We present a case of suspected AGE following orthotopic heart transplant. The patient received hyperbaric oxygen therapy with near-complete resolution of symptoms at follow-up. This case exemplifies the difficulty in diagnosis of AGE, the considerations involved in the treatment of a critical care patient in a hyperbaric chamber, and utility in treating a patient for AGE even after a delay in diagnosis.

Complex neurological symptoms in bilateral thalamic stroke due to Percheron artery occlusion.

The artery of Percheron is a rare anatomical variant where a single thalamic perforating artery arises from the proximal posterior cerebral artery (P1 segment) between the basilar artery and the posterior communicating artery and supplies the rostral mesencephalon and both paramedian territories of the thalami. Almost one-third of human brains present this variant. Occlusion of the artery of Percheron mostly results in a bilateral medial thalamic infarction, which usually manifests with altered consciousness (including coma), vertical gaze paresis, and cognitive disturbance. The presentation is similar to the "top of the basilar syndrome", and early recognition should be prompted. We describe the case of a young female with this vessel variant who experienced a bilateral thalamic stroke. Magnetic resonance angiography demonstrated bilateral thalamic infarcts and a truncated artery of Percheron. Occlusion of the vessel was presumably due to embolism from a patent foramen ovale. Thrombolysis was performed, with incomplete symptom remission, cognitive impairment, and persistence of speech disorders. Early recognition and treatment of posterior circulation strokes is mandatory, and further investigation for underlying stroke etiologies is needed.

Endoscopic Bubble Trouble: Hyperbaric Oxygen Therapy for Cerebral Gas Embolism During Upper Endoscopy.

Gas embolism is a rare but potentially devastating complication of endoscopic procedures. We describe 3 cases of gas embolism which were associated with endoscopic procedures (esophagogastroduodenoscopy and endoscopic retrograde cholangiopancreatography). We treated these at our hyperbaric medicine center with 3 different outcomes: complete resolution, death, and disability. We review the literature regarding this unusual complication of endoscopy and discuss the need for prompt identification and referral for hyperbaric oxygen therapy. Additional adjunctive therapies are also discussed.

Use of Dual Antiplatelet Therapy and Patient Outcomes in Those Undergoing Percutaneous Coronary Intervention: The ROCKET AF Trial.

OBJECTIVES: The authors assessed the use of dual antiplatelet therapy (DAPT) and outcomes in patients undergoing percutaneous coronary intervention (PCI) during the ROCKET AF (Rivaroxaban Once Daily Oral Direct Factor Xa Inhibition Compared with Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation). BACKGROUND: The frequency, patterns, and outcomes when adding DAPT to non-vitamin K antagonist oral anticoagulants in the setting of PCI in patients with AF are largely unknown. METHODS: The study population included all patients in the treatment group of the ROCKET AF trial divided by the receipt of PCI during follow-up. Clinical characteristics, PCI frequency, and rates of DAPT were reported. Clinical outcomes were adjudicated independently as part of the trial. RESULTS: Among 14,171 patients, 153 (1.1%) underwent PCI during a median 806 days of follow-up. Patients treated with rivaroxaban were significantly less likely to undergo PCI compared with warfarin-treated patients (61 vs. 92; p = 0.01). Study drug was continued during PCI in 81% of patients. Long-term DAPT (≥30 days) was used in 37% and single antiplatelet therapy in 34%. A small number switched from DAPT to monotherapy within 30 days of PCI (n = 19 [12.3%]) and 15% of patients received no antiplatelet therapy after PCI. Rates of stroke/systemic embolism and major bleeding events were high in post-PCI patients (4.5/100 patient-years and 10.2/100 patient-years) in both treatment groups. CONCLUSIONS: In patients with AF at moderate to high risk for stroke, PCI occurred in <1% per year. DAPT was used in a variable manner, with the majority of patients remaining on study drug after PCI. Rates of both thrombotic and bleeding events were high after PCI, highlighting the need for studies to determine the optimal antithrombotic therapy.

Prognosis of cerebral lipiodol embolism caused by transarterial chemoembolization.

OBJECTIVES: Transarterial chemoembolization (TACE) plays an essential role in the management of unresectable hepatocellular cell carcinoma and other hepatic neoplasms. Cerebral lipiodol embolism (CLE) is a rare complication of TACE and its prognostic factors have not been well studied. The aim of this paper was to elucidate the prognostic factors of CLE based on clinical data obtained from our patients and cases published since 2004. METHODS: We present two patients with CLE, analyze the clinical data, and review all CLE cases published since 2004. A poor outcome was defined as stupor, coma, quadriplegia, or death within 45 days. Patients who had other neurological conditions within 45 days were considered as having a good outcome. RESULTS: The rate of poor outcome was 25.7% (9/35). Compared with the patients with good outcome, those with poor outcome were older (mean age 68.3 ± 7.3 vs. 58.3 ± 10.6 years, p = 0.03), more often female (76.9% vs. male 33.3%, p = 0.02), and more likely chemoembolized via both the right hepatic and right inferior phrenic arteries (44.4 vs. 8.7%, p = 0.02). DISCUSSION: The prognosis of CLE was related to age, gender, and the arteries selected for injection.

Early Rivaroxaban Use After Cardioembolic Stroke May Not Result in Hemorrhagic Transformation: A Prospective Magnetic Resonance Imaging Study.

BACKGROUND AND PURPOSE: Early anticoagulation after cardioembolic stroke remains controversial because of the potential for hemorrhagic transformation (HT). We tested the safety and feasibility of initiating rivaroxaban ≤14 days after cardioembolic stroke/transient ischemic attack. METHODS: A prospective, open-label study of patients with atrial fibrillation treated with rivaroxaban ≤14 days of transient ischemic attack or ischemic stroke (National Institute of Health Stroke Scale <9). All patients underwent magnetic resonance imaging <24 hours of rivaroxaban initiation and day 7. The primary end point was symptomatic HT at day 7. RESULTS: Sixty patients (mean±SD age 71±19 years, 82% stroke/18% transient ischemic attack) were enrolled. Median (interquartile range) time from onset to rivaroxaban was 3 (5) days. At treatment initiation, median National Institute of Health Stroke Scale was 2 (4), and median diffusion-weighted imaging volume was 7.9 (13.7) mL. At baseline, HT was present in 25 (42%) patients (hemorrhagic infarct [HI]1=19, HI2=6). On follow-up magnetic resonance imaging, no patients developed symptomatic HT. New asymptomatic HI1 developed in 3 patients, and asymptomatic progression from HI1 to HI2 occurred in 5 patients; otherwise, HT remained unchanged at day 7. CONCLUSIONS: These data support the safety of rivaroxaban initiation ≤14 days of mild-moderate cardioembolic stroke/transient ischemic attack. Magnetic resonance imaging evidence of petechial HT, which is common, does not appear to increase the risk of symptomatic HT.