Air embolism caused by peripheral superficial vein catheterization: A case report

BACKGROUND

Air embolization is usually an iatrogenic complication that can occur in both veins and arteries. Intravenous air embolization is mainly associated with large central vein catheters and mechanical ventilation. A 59-year-old woman was sent to our hospital with spontaneous cerebral hemorrhage and treated conservatively with a left forearm peripheral venous catheter infusion drug. After 48 hours, the patient's oxygen saturation decreased to 92 % with snoring breathing. Computer tomography of the head and chest revealed scattered gas in the right subclavian, the right edge of the sternum, the superior vena cava, and the leading edge of the heart shadow.

METHODS

She was sent to the intensive care unit for high-flow oxygen inhalation and left-side reclining instantly. As the patient was at an acute stage of cerebral hemorrhage and did not take the Trendelenburg position.

RESULTS

The computed tomography (CT) scan after 24 hours shows that the air embolism subsides.

CONCLUSION SUBSECTIONS

Air embolism can occur in any clinical scenario, suggesting that medical staff should enhance the ability to identify and deal with air embolism. For similar cases in clinical practice, air embolism can be considered.

The impact of increasing saline flush volume to reduce the amount of residual air in the delivery system of aortic prostheses-a randomized controlled trial

Background

Air embolism is a known risk during thoracic endovascular aortic repair (TEVAR) and is associated with an incomplete deairing of the delivery system despite the saline lavage recommended by the instructions for use (IFU). As the delivery systems are identical and residual air remains frequently in the abdominal aortic aneurysm sac, endovascular aortic repair (EVAR) can be used to examine the effectiveness of deairing maneuvers. We aimed to evaluate whether increasing the flush volume can result in a more complete deairing.

Methods

Patients undergoing EVAR were randomly assigned according to flushing volume (Group A, 1× IFU; Group B, 4× IFU). The Terumo Aortic Anaconda and Treo and Cook Zenith Alpha Abdominal stent grafts were randomly implanted in equal distribution (10-10-10). The quantity of air trapped in the aneurysm sac was measured using a pre-discharge computed tomography angiography (CTA). Thirty patients were enrolled and equally distributed between the two groups, with no differences observed in any demographic or anatomical factors.

Results

The presence of air was less frequent in Group A compared to that in Group B [7 (47%) vs. 13 (87%), p = .02], and the air volume was less in Group A compared to that in Group B (103.5 ± 210.4 vs. 175.5 ± 175.0 mm3, p = .04). Additionally, the volume of trapped air was higher with the Anaconda graft type (p = .025).

Discussion

These findings suggest that increased flushing volume is associated with a higher amount of trapped air; thus, following the IFU might be associated with a reduced risk of air embolization. Furthermore, significant differences were identified between devices in terms of the amount of trapped air.

Clinical trial registration

[NCT04909190], [ClinicalTrials.gov].

Corrigendum: Iatrogenic air embolism: pathoanatomy, thromboinflammation, endotheliopathy, and therapies

[This corrects the article DOI: 10.3389/fimmu.2023.1230049.].

Umbilical vein catheterisation for the family physician working in primary health care

This is part of a series of articles on vascular access in emergencies. The other two articles were on intra osseous lines and central venous lines. These are critical lifesaving emergency skills for the primary care professional. In this article, we will provide an overview of umbilical vein catheterisation highlighting its importance, the indications, contraindications, techniques, complications and nursing considerations. By familiarising healthcare providers with this procedure, we hope to enhance their knowledge and skills, ultimately leading to improved outcomes in the neonatal population.

Iatrogenic air embolism: pathoanatomy, thromboinflammation, endotheliopathy, and therapies

Iatrogenic vascular air embolism is a relatively infrequent event but is associated with significant morbidity and mortality. These emboli can arise in many clinical settings such as neurosurgery, cardiac surgery, and liver transplantation, but more recently, endoscopy, hemodialysis, thoracentesis, tissue biopsy, angiography, and central and peripheral venous access and removal have overtaken surgery and trauma as significant causes of vascular air embolism. The true incidence may be greater since many of these air emboli are asymptomatic and frequently go undiagnosed or unreported. Due to the rarity of vascular air embolism and because of the many manifestations, diagnoses can be difficult and require immediate therapeutic intervention. An iatrogenic air embolism can result in both venous and arterial emboli whose anatomic locations dictate the clinical course. Most clinically significant iatrogenic air emboli are caused by arterial obstruction of small vessels because the pulmonary gas exchange filters the more frequent, smaller volume bubbles that gain access to the venous circulation. However, there is a subset of patients with venous air emboli caused by larger volumes of air who present with more protean manifestations. There have been significant gains in the understanding of the interactions of fluid dynamics, hemostasis, and inflammation caused by air emboli due to in vitro and in vivo studies on flow dynamics of bubbles in small vessels. Intensive research regarding the thromboinflammatory changes at the level of the endothelium has been described recently. The obstruction of vessels by air emboli causes immediate pathoanatomic and immunologic and thromboinflammatory responses at the level of the endothelium. In this review, we describe those immunologic and thromboinflammatory responses at the level of the endothelium as well as evaluate traditional and novel forms of therapy for this rare and often unrecognized clinical condition.

A human cadaveric model for venous air embolism tool development

Purpose

A human cadaveric model combining standard lung protective mechanical ventilation and modified cardiac bypass techniques was developed to allow investigation into automated modes of detection of venous air emboli (VAE) prior to in vivo human or animal investigations.

Methods

In this study, in order to create an artificial cardiopulmonary circuit in a cadaver that could mimic VAE physiology, the direction of flow was reversed from conventional cardiac bypass. Saline was circulated in isolation through the heart and lungs as opposed to the peripheral organs by placing the venous cannula into the aorta and the arterial cannula into the inferior vena cava with selective ligation of other vessels.

Results

Mechanical ventilation and this reversed cardiac bypass scheme allowed preliminary detection of VAE independently but not in concert in our current simulation scheme due to pulmonary edema in the cadaver. A limited dissection approach was used initially followed by a radical exposure of the great vessels, and both proved feasible in terms of air signal detection. We used electrical impendence as a preliminary tool to validate detection in this cadaveric model however we theorize that it would work for echocardiographic, intravenous ultrasound or other novel modalities as well.

Conclusion

A cadaveric model allows monitoring technology development with reduced use of animal and conventional human testing.

Air Embolism: A Rare Lethal Complication of Hysteroscopy in a Young Woman Undergoing Infertility Workup

Compared to operative hysteroscopy, diagnostic hysteroscopy rarely leads to issues. However, one very uncommon yet potentially fatal complication is air embolism, with an incidence rate of three in 17,000 cases. This report describes an unexpected complication discovered during diagnostic hysteroscopy surgery. In the course of routine infertility testing, a 29-year-old woman underwent a diagnostic hysteroscopy under general anesthesia. Intraoperatively, her end-tidal carbon dioxide (EtCO2) levels decreased, oxygen saturation dropped, and heart rate increased, leading the anesthesiologists and critical care team to terminate the procedure and manage her further. Subsequent transesophageal echocardiography confirmed the diagnosis of air embolism. She was managed with 100% oxygen and inotropes and cardiopulmonary resuscitation but despite aggressive medical interventions, her condition did not improve, and she unfortunately passed away. To diagnose, prevent, and manage the potentially devastating consequences associated with diagnostic hysteroscopy, gynecologists and surgical teams must maintain vigilance. The focus should be on proper patient selection, optimal surgical techniques, and the use of high-quality equipment to mitigate the risk of air embolism.

Suspected systemic gas embolism associated with lung tissue perforation caused by a previously inserted chest drain in a dog

OBJECTIVE

To report a case of systemic gas embolism associated with removal of a chest drain perforating a lung lobe in a dog undergoing sternotomy under general anesthesia and intermittent positive pressure ventilation.

CASE SUMMARY

An 8-year-old Cocker Spaniel underwent an exploratory thoracotomy via median sternotomy for surgical management of pyothorax that was treated conservatively for 7 days prior to referral following bilateral chest drain placement. The surgical procedure consisted of a subphrenic mediastinectomy and pericardiectomy. During surgery, it became apparent that the right drain was perforating the right middle lung lobe. Sudden desaturation and rapid hemodynamic deterioration occurred after the drain was removed. A systemic gas embolism was suspected on the basis of clinical signs and results of an arterial blood gas analysis, and immediate supportive treatment was started with an adequate response. Once the surgical procedure was completed, a clear "mill wheel" sound was audible on cardiac auscultation and point-of-care cardiac ultrasound confirmed the presence of gas bubbles in the cardiac chambers. The dog recovered from anesthesia and was managed in the intensive care unit where arterial blood gas analyses were nearly normal and the dog made a full recovery.

NEW OR UNIQUE INFORMATION PROVIDED

In people, there are reports of fatal air embolism related to the use of chest drains. To our knowledge, this is the first case report in dogs of a systemic gas embolism during open-chest surgery caused by a chest drain perforating a lung lobe. Immediate recognition and aggressive treatment of this life-threatening condition should be provided in order to achieve a favorable outcome.

Comparison of bubble removal performances of five membrane oxygenators with and without a pre-filter

When employing minimal invasive extracorporeal circulation (MiECC), the removal of bubbles in the circuit is important to prevent air embolism. We investigated the bubble removal performance of the FHP oxygenator with a pre-filter and compared it with that of four oxygenators, including the Fusion oxygenator, Quadrox oxygenator, Inspire oxygenator, and FX oxygenator. A closed test circuit filled with an aqueous glycerin solution was used. Air injection (10 mL) was performed prior to the oxygenator, and the number and volume of the bubbles were measured at the inlet and outlet of each oxygenator. At the inlet of the five oxygenators, there were no significant differences in the total number of bubbles detected. At the outlet, bubbles were classified into two groups according to the bubble size: ≥100 μm and <100 μm. Tests were performed at pump flow rates of 4 and 5 L/min. For bubbles ≥100 μm, which are considered clinically detrimental, the FHP was the lowest number and volume of bubbles at both pump flow rates compared to the other oxygenators. Regarding the bubbles <100 μm, the number of bubbles was higher in the FHP than those in others; however, the volume of bubbles was significantly lower at 4 L/min and tended to be lower at 5 L/min. The use of the FHP with the pre-filter removed more bubbles ≥100 μm in the circuit than that by the other oxygenators.

Carbon Dioxide Pyelography: A Convenient and Safe Alternative to Both Room Air and Iodinated Contrast Pyelography During Endourologic Procedures

Introduction/Background: There are increasing reports of serious complications related to the air pyelography technique, which raise concerns about the safety of room air (RA) injection into the renal collecting system. Carbon dioxide (CO2) is much more soluble in blood than nitrogen and oxygen and thus considerably less likely to cause gas emboli. Iodinated contrast medium (ICM) is expensive, and supplies may not be as reliable as previously assumed. CO2 pyelography (CO2-P) techniques using standard fluoroscopy and digital subtraction fluoroscopy (CO2 digital subtraction pyelography [CO2-DSP]) are described. Materials and Methods: During the endourologic stone cases, 15 to 20 mL of CO2 gas was typically injected into the renal pelvis through a catheter or sheath. Imaging was usually obtained with endovascular CO2 digital subtraction angiography settings using either a traditional fluoroscopy system (TFS) or robotic arm multiplanar fluoroscopy system (RMPFS) (Artis Zeego Care+Clear®; Siemens). Results: CO2-P was performed in 22 endoscopic stone treatment cases between March 2021 and August 2022, primarily using digital subtraction settings in 20 cases. CO2-DSP overall provided higher quality images of the renal pelvis and collecting system than CO2-P, but with a relatively higher radiation dose. Following a quality intervention, fluoroscopy doses for CO2-DSP cases were decreased by 81% overall. The use of CO2-P avoided fluoroscopic or intraoperative CT (ICT) artifacts seen with intraluminal ICM. Conclusions: CO2-P allows the urologist to obtain imaging of the renal collecting system without ICM and with much lower risk of air embolism compared with RA pyelography. CO2 is a nearly cost-free alternative to ICM. Because CO2 is widely available and the technique is easy to perform, we propose that CO2-P should be favored over traditional air pyelography to improve patient safety.

Anaesthetic Management of a Foramen Magnum Meningioma Resection Surgery: A Case Report

The foramen magnum meningioma (FMM) is one of the most threatening tumours among the meningiomas because of its specific location, clinical course, subtle onset, and relatively big dimensions at presentation. Tumour size may mandate careful airway management to avoid further brainstem compression. The surgical management of these complex tumours in the posterior fossa can be performed with the patient in several positions. A lot of surgeons believe the sitting position provides important advantages, yet this remains controversial. We report a successful approach to a large FMM resection surgery performed in the sitting position.

Intraoperative air embolism diagnosis and treatment using hyperbaric oxygen therapy after craniotomy: illustrative case

BACKGROUND

This report describes the use of hyperbaric oxygen therapy for the acute management of an intraoperative air embolism encountered during a neurosurgical procedure. Furthermore, the authors highlight the concomitant diagnosis of tension pneumocephalus requiring evacuation prior to hyperbaric therapy.

OBSERVATIONS

A 68-year-old male developed acute ST-segment elevation and hypotension during elective disconnection of a posterior fossa dural arteriovenous fistula. The semi-sitting position had been used to minimize cerebellar retraction, raising the concern for acute air embolism. Intraoperative transesophageal echocardiography was utilized to establish the diagnosis of air embolism. The patient was stabilized on vasopressor therapy, and immediate postoperative computed tomography revealed air bubbles in the left atrium along with tension pneumocephalus. He underwent urgent evacuation for the tension pneumocephalus followed by hyperbaric oxygen therapy to manage the hemodynamically significant air embolism. The patient was eventually extubated and went on to fully recover; a delayed angiogram revealed complete cure of the dural arteriovenous fistula.

LESSONS

Hyperbaric oxygen therapy should be considered for an intracardiac air embolism resulting in hemodynamic instability. In the postoperative neurosurgical setting, care should be taken to exclude pneumocephalus requiring operative intervention prior to hyperbaric therapy. A multidisciplinary management approach facilitated expeditious diagnosis and management for the patient.

An unusual case of neurocardiogenic syncope: A case report and systematic review

We present a case of syncopal episode in emergency department (ED) and subsequent admission to the geriatric assessment unit. The patient presented with self-limiting central abdominal pain. Given a history of previous aortic aneurysm repair, a contrast CT angiogram was performed. With no evidence of leaking aneurysm, the patient was discharged from the ED. The syncopal episode happened while waiting for a taxi. A review of the earlier CT scan showed the presence of air in the venous circulatory system. In hindsight, it was thought the syncopal episode occurred due to air embolism introduced during or shortly after venous cannulation. We discuss the aetiology of venous air embolism and highlight the lack of evidence regarding tolerable amounts of air in the circulatory system. Physiological changes associated with age may suggest that elderly patients are uniquely maladapted to overcome sudden insults to their cardiovascular status.

Alda-1 ameliorates air embolism-induced acute lung injury

OBJECTIVE

Evidence suggests that aldehyde dehydrogenase 2 (ALDH2) offers protection against damage caused by oxidative stress in diverse rodent models. Nonetheless, the effect of Alda-1, a compound that activates ALDH2, on acute lung injury (ALI) induced by air embolism (AE) remains unclear. The objective of this study was to explore the protective effects of Alda-1 in ALI induced by AE.

METHODS

A rat model of in situ isolated perfused lung was established to investigate AE-induced ALI. Air was infused into the pulmonary artery at 0.25 mL/min for 1 minute. Before inducing AE, different doses (10, 20, or 30 mg/kg) of Alda-1 were given through intraperitoneal injection. Pathological changes in lung tissue were assessed using hematoxylin-eosin staining. We performed Western blot analysis to assess the protein levels of ALDH2,4-hydroxy-trans-2-nonenal (4-HNE), Bcl-2, caspase-3, phosphatidylinositol 3-kinase (PI3K), Akt, IκB-α, and nuclear NF-κB.

RESULTS

Notably, AE results were demonstrated as harmful to the lungs, which is evidenced by intensified lung edema and disruption of lung tissue structure. Furthermore, AE caused a decrease in ALDH2 expression, increased accumulation of 4-HNE and MDA, infiltration of neutrophils, increased production of inflammatory cytokines, apoptosis, and upregulation of the PI3K/Akt and NF-κB signaling pathways within the lungs. Administration of a 20 mg/kg dose of Alda-1 alleviated the detrimental effects induced by AE.

CONCLUSION

Alda-1 shows promise in mitigating AE-induced ALI, possibly through the upregulation of ALDH2 expression and suppression of the PI3K/Akt and NF-κB signaling pathways. Further research is warranted to validate these findings and to explore their translational potential in human subjects.

Acquired atrioesophageal fistula: Need it be lethal? Sizing up the problem, diagnostic modalities, and best management

BACKGROUND AND AIM OF THE STUDY

An atrioesophageal fistula is a devastating complication of ablation for atrial fibrillation. For the surgeon facing this dreaded complication, it may be a 'once in a lifetime' case. This review aims to describe the clinical problem and evaluate the outcome of different surgical techniques to start guiding cardiothoracic surgeons toward those which offer the best chance of survival.

METHODS

An electronic search retrieved 125 articles containing 195 cases of atrioesophageal fistula secondary to atrial fibrillation ablation. Reports of pericardio-esophageal or mediastino-esophageal fistula were excluded.

RESULTS

The median age was 61 and 143 (73%) cases occurred in males. Fever (n = 147; 75%) and neurological dysfunction (n = 151; 77%) were the most common symptoms. The median time from ablation to symptom onset was 21 days (interquartile range: 12-28). The most sensitive thoracic imaging modality was computed tomography (n = 135/153; 90%). Immediate deterioration occurred during 11/58 (19%) oesophago-gastro-duodenoscopies. Mortality was lower in patients who had surgery (39%) compared with endoscopic intervention (94%) or conservative management (97%). Patients who had atrial repair combined with esophageal repair or oesophagectomy were more likely to survive than those who had atrial repair alone (OR 6.97; p < .001). Isolation of the esophageal aspect of the fistula conferred an additional survival benefit (OR 5.85; p = .02).

CONCLUSIONS

Fever, neurological symptoms, and chest pain in the context of recent ablation should prompt immediate evaluation. Urgent CT thorax should be arranged and repeated if initially unremarkable. Esophageal instrumentation should be avoided due to the risk of catastrophic air embolism or massive hemorrhage. The best way forward is emergency surgical repair; the combination which offers the best survival benefit is atrial repair combined with esophageal surgery and isolation of the esophageal aspect of the fistula.

Left Heart and Systemic Arterial Circulation Air Embolus During CT-Guided Lung Biopsy

A transthoracic needle biopsy (TTNB) of the lung, commonly referred to as a "lung biopsy," is a commonly performed procedure in Interventional Radiology. It is usually associated with well-known risks including pneumothorax and hemothorax. One of the rare and lesser-known risks of TTNB, however, is a phenomenon called an air embolism. The term "air embolism" alone may be somewhat ambiguous, as it could indicate i) air entering the systemic veins, or ii) air entering the pulmonary veins. Here, we present a case of an air embolus entering the pulmonary veins. The pulmonary veins naturally drain into the left side of the heart (left atrium and ventricle) which provides oxygenated blood to the major arteries of the body including the coronary, carotid, and major abdominal visceral branches. Therefore, an air embolism in this vasculature can lead to potentially devastating hemodynamic consequences downstream.

Venous Air Embolism Activates Complement C3 Without Corresponding C5 Activation and Trigger Thromboinflammation in Pigs

Introduction

Air embolism may complicate invasive medical procedures. Bubbles trigger complement C3-mediated cytokine release, coagulation, and platelet activation in vitro in human whole blood. Since these findings have not been verified in vivo, we aimed to examine the effects of air embolism in pigs on thromboinflammation.

Methods

Forty-five landrace pigs, average 17 kg (range 8.5-30), underwent intravenous air infusion for 300 or 360 minutes (n=29) or served as sham (n=14). Fourteen pigs were excluded due to e.g. infections or persistent foramen ovale. Blood was analyzed for white blood cells (WBC), complement activation (C3a and terminal C5b-9 complement complex [TCC]), cytokines, and hemostatic parameters including thrombin-antithrombin (TAT) using immunoassays and rotational thromboelastometry (ROTEM). Lung tissue was analyzed for complement and cytokines using qPCR and immunoassays. Results are presented as medians with interquartile range.

Results

In 24 pigs receiving air infusion, WBC increased from 17×10⁹/L (10-24) to 28 (16-42) (p<0.001). C3a increased from 21 ng/mL (15-46) to 67 (39-84) (p<0.001), whereas TCC increased only modestly (p=0.02). TAT increased from 35 µg/mL (28-42) to 51 (38-89) (p=0.002). ROTEM changed during first 120 minutes: Clotting time decreased from 613 seconds (531-677) to 538 (399-620) (p=0.006), clot formation time decreased from 161 seconds (122-195) to 124 (83-162) (p=0.02) and α-angle increased from 62 degrees (57-68) to 68 (62-74) (p=0.02). In lungs from pigs receiving air compared to sham animals, C3a was 34 ng/mL (14-50) versus 4.1 (2.4-5.7) (p<0.001), whereas TCC was 0.3 CAU/mL (0.2-0.3) versus 0.2 (0.1-0.2) (p=0.02). Lung cytokines in pigs receiving air compared to sham animals were: IL-1β 302 pg/mL (190-437) versus 107 (66-120), IL-6 644 pg/mL (358-1094) versus 25 (23-30), IL-8 203 pg/mL (81-377) versus 21 (20-35), and TNF 113 pg/mL (96-147) versus 16 (13-22) (all p<0.001). Cytokine mRNA in lung tissue from pigs receiving air compared to sham animals increased 12-fold for IL-1β, 121-fold for IL-6, and 17-fold for IL-8 (all p<0.001).

Conclusion

Venous air embolism in pigs activated C3 without a corresponding C5 activation and triggered thromboinflammation, consistent with a C3-dependent mechanism. C3-inhibition might represent a therapeutic approach to attenuate this response.

Investigation of Experimental Endovascular Air Embolisms Using a New Model for the Generation and Detection of Highly Calibrated Micro Air Bubbles

BACKGROUND

Air embolism (AE), especially when affecting the brain, is an underrated and potentially life-threatening complication in various endovascular interventions. This study aims to investigate experimental AEs using a new model to generate micro air bubbles (MAB), to assess the impact of a catheter on these MAB, and to demonstrate the applicability of this model in vivo.

MATERIALS AND METHODS

Micro air bubbles were created using a system based on microfluidic channels. The MAB were detected and analyzed automatically. Micro air bubbles, with a target size of 85 µm, were generated and injected through a microcatheter. The MAB diameters proximal and distal to the catheter were assessed and compared. In a subsequent in vivo application, 2000 MAB were injected into the aorta (at the aortic valve) and into the common carotid artery (CCA) of a rat, respectively, using a microcatheter, resembling AE occurring during cardiovascular interventions.

RESULTS

Micro air bubbles with a highly calibrated size could be successfully generated (median: 85.5 µm, SD 1.9 µm). After passage of the microcatheter, the MAB were similar in diameter (median: 86.6 µm) but at a lower number (60.1% of the injected MAB) and a substantially higher scattering of diameters (SD 29.6 µm). In vivo injection of MAB into the aorta resulted in cerebral microinfarctions in both hemispheres, whereas injection into the CCA caused exclusively ipsilateral microinfarctions.

CONCLUSION

Using this new AE model, MAB can be generated precisely and reproducibly, resulting in cerebral microinfarctions. This model is feasible for further studies on the pathophysiology and prevention of AE in cardiovascular procedures.

Abstract No.: ABS0480: A retrospective study observing outcome following posterior fossa craniotomy in patients with sitting position

Background & Aims:

Methods:

Results:

Conclusion:

Acute air embolism caused by autotransfusion during percutaneous atrial septal defect closure: A case report

Atrial septal defect is a common congenital heart disease in adults and it is often asymptomatic. Percutaneous device closure is gaining popularity, but percutaneous repair of atrial septal defect leading to left atrial rupture and subsequent autotransfusion under high pressure leading to air embolism has not been reported yet.

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.

Fatal air embolism: A grave complication during diagnostic flexible bronchoscopy

Flexible fiber-optic bronchoscopy is used to determine diagnoses in pulmonary diseases. It is considered as a safe procedure, although some complications might occur, one of which is cerebral air embolism. In this case, we present the air embolism after the bronchoscopy procedure, ending in fatality. We strongly recommend that bronchoscopists should keep this complication in mind and be aware of early symptoms pertaining to the patient's state of consciousness during bronchoscopy examination. Early treatment is essential in this situation.

Massive cerebral air embolism following percutaneous transhepatic biliary drainage: A case report

RATIONALE

Cerebral air embolism from portal venous gas rarely occurs due to invasive procedures (e.g., endoscopic procedures, liver biopsy, or percutaneous transhepatic biliary drainage) that disrupt the gastrointestinal or hepatobiliary structures. Here, we report a rare case of fatal cerebral air embolism following a series of percutaneous transhepatic biliary drainage tube insertions.

PATIENT CONCERNS

A 50-year-old woman with a history of cholecystectomy, liver wedge resection, and hepaticojejunostomy for gallbladder cancer presented with altered mental status 1 week after percutaneous transhepatic biliary drainage tube placement.

DIAGNOSES

Extensive cerebral air embolism and acute cerebral infarction.

INTERVENTIONS

Brain computed tomography and magnetic resonance imaging, hyperbaric oxygen therapy, medical therapy.

OUTCOMES

Despite the use of hyperbaric oxygen therapy and medical treatment including vasopressors, the patient eventually died due to massive systemic air embolism.

LESSONS

To date, there have been no reports of cerebral air embolism due to percutaneous transhepatic biliary drainage with pronounced radiologic images. We reviewed previously reported fatal cases associated with endoscopic hepatobiliary procedures and assessed the possible mechanisms and potential causes of air embolism.

Caution: Air Embolism Related to Heli-Fx EndoAnchor System in Zone 2 Thoracic Aneurysm Repair

PURPOSE

We report a case of significant air embolization to the ascending aorta immediately following deployment of EndoAnchors in the aortic arch during a procedure to correct a type 1A endoleak.

CASE REPORT

The novel Heli-Fx EndoAnchor system (Medtronic Vascular, Santa Rosa, CA, USA) was used to deploy helical anchors in the distal aortic arch during a procedure to correct a type 1A endoleak following Zone 2 thoracic endovascular aortic repair of a saccular proximal descending thoracic aorta aneurysm (DTAA). The patient developed ST-segment elevations principally in the inferior leads and severe hypotension moments after EndoAnchor deployment at the proximal edge of the endograft. Transesophageal echocardiogram revealed severe right ventricular hypokinesis and a large amount of air in the ascending aorta. Subsequent management and clinical and radiological 30-day follow-up is presented in addition to a review of the literature and ex vivo testing with the Heli-Fx system to examine potential causes and solutions.

CONCLUSION

Precautions, such as pressurized saline infusion to the side port of guiding sheath, should be used whenever manipulating catheters and sheaths such as the EndoAnchor system in the aortic arch to prevent this potentially lethal complication.

[Paradoxical air embolism of intracerebral arteries as a complication of tooth extraction]

The article describes the rare clinical case, demonstrating sudden onset of neurological manifestations (seizures and consequent formation of ischemic stroke foci) in a 29 year-old female patient during tooth extraction (right lower third molar) using the high-speed dental drill. Air injection through damaged tissues caused subcutaneous emphysema in the buccal area that caused air embolism. Presence of asymptomatic congenital heart defect in the patient (atrial septal defect) allowed the bubbles of air to move paradoxically from right to left with consequent embolization of small cerebral arteries. Treatment in specialized department was successful and had beneficial effect on patient's condition.

Seizures in Iatrogenic Cerebral Arterial Gas Embolism

Supplemental Digital Content is available in the text.

Objectives:

Iatrogenic cerebral arterial gas embolism occurs when gas enters the cerebral arterial circulation during a medical procedure and is considered a severe complication. Seizures have been described in these patients, but information on clinical characteristics, treatment, and outcome is lacking in current literature. The aim of the study was to explore seizures in patients with iatrogenic cerebral arterial gas embolism and to evaluate management strategies.

Design:

Retrospective single-center observational study.

Setting:

The only university hospital in the Netherlands with a hyperbaric oxygen therapy facility.

Patients:

All patients presenting at or referred to our center with iatrogenic cerebral arterial gas embolism between May 2016 and December 2020.

Interventions:

Not applicable.

Measurements and Main Results:

Fifteen patients with iatrogenic cerebral arterial gas embolism were identified, of whom 11 (73%) developed seizures. Five patients developed their first seizure prior to hyperbaric oxygen therapy, three during hyperbaric oxygen therapy, and three after hyperbaric oxygen therapy. Of the 11 patients with seizures, all but one were treated with anti-epileptic drugs. With a median follow-up time of 5 months (range, 1–54 mo), five patients showed complete neurologic recovery, five had minor neurologic deficit, two had moderate to severe neurologic deficit, and three had died. Four patients still used anti-epileptic drugs at follow-up. No patients had recurrent seizures after hospital discharge.

Conclusions:

`Seizures are a common symptom in iatrogenic cerebral arterial gas embolism. They are often treated with anti-epileptic drugs and do not seem to lead to chronic epilepsy.

Clinically Manifesting Air Embolisms in Cryoballoon Ablation: Can Novel Water Buckets Reduce the Risk?

Air embolisms can lead to lethal results; however, few reports have systemically investigated this issue. Of 348 consecutive patients with atrial fibrillation who underwent cryoballoon ablation, procedures were performed conventionally in 251 patients. In the remaining 97 patients, a water bucket was used while inserting the cryoballoon into the sheath. A total of 10 coronary air embolisms with ST-segment elevation in the inferior leads were observed among 9 (2.6%) patients. Multiple air bubbles were identified in 2 patients on emergent coronary angiography. All recovered under conservative treatment without any sequela. The incidence decreased when using the water bucket (1 of 97 [1.03%] vs. 8 of 251 [3.2%], p = 0.454).

Clinical presentation, diagnosis, and treatment of atrioesophageal fistula resulting from atrial fibrillation ablation

BACKGROUND

Atrioesophageal fistula (AEF) is a worrisome complication of atrial fibrillation (AF) ablation. Its clinical manifestations and time course are unpredictable and may contribute to diagnostic and treatment delays. We conducted a systematic review of all available cases of AEF, aiming at characterizing clinical presentation, time course, diagnostic pitfalls, and outcomes.

METHODS

The digital search retrieved 150 studies containing 257 cases, 238 (92.6%) of which with a confirmed diagnosis of AEF and 19 (7.4%) of pericardioesophageal fistula.

RESULTS

The median time from ablation to symptom onset was 21 days (interquartile range [IQR]: 11-28). Neurological abnormalities were documented in 75% of patients. Compared to patients seen by a specialist, those evaluated at a walk-in clinic or community hospital had a significantly greater delay between symptom onset and hospital admission (median: 2.5 day [IQR: 1-8] vs. 1 day [IQR: 1-5); p = .03). Overall, 198 patients underwent a chest scan (computed tomography [CT]: 192 patients and magnetic resonance imaging [MRI]: 6 patients), 48 (24.2%; 46 CT and 2 MRI) of whom had normal/unremarkable findings. Time from hospital admission to diagnostic confirmation was significantly longer in patients with a first normal/unremarkable chest scan (p < .001). Overall mortality rate was 59.3% and 26.0% survivors had residual neurological deficits at the time of discharge.

CONCLUSIONS

Since healthcare professionals of any specialty might be involved in treating AEF patients, awareness of the clinical manifestations, diagnostic pitfalls, and time course, as well as an early contact with the treating electrophysiologist for a coordinated interdisciplinary medical effort, are pivotal to prevent diagnostic delays and reduce mortality.

Flow field around bubbles on formation of air embolism in small vessels

An air embolism is induced by intravascular bubbles that block the blood flow in vessels, which causes a high risk of pulmonary hypertension and myocardial and cerebral infarction. However, it is still unclear how a moving bubble is stopped in the blood flow to form an air embolism in small vessels. In this work, microfluidic experiments, in vivo and in vitro, are performed in small vessels, where bubbles are seen to deform and stop gradually in the flow. A clot is always found to originate at the tail of a moving bubble, which is attributed to the special flow field around the bubble. As the clot grows, it breaks the lubrication film between the bubble and the channel wall; thus, the friction force is increased to stop the bubble. This study illustrates the stopping process of elongated bubbles in small vessels and brings insight into the formation of air embolism.

Fatal systemic (paradoxical) air embolism diagnosed by postmortem funduscopy

Air embolism is often unrecognized and underreported. Published case reports or case series describe only rare fundal examinations of retinal air emboli (RAE)-a distinctive sign of systemic air embolism. We report an infant, found unresponsive at home, who died in the emergency department after unsuccessful resuscitative efforts. Before the autopsy, diagnostic RAE were recognized and imaged during postmortem funduscopy. Postmortem radiography and an autopsy confirmed systemic (paradoxical) air embolism due to inflicted abdominal and thoracic blunt force injuries. While a few descriptions and illustrations of RAE occur in case reports, we found no published photographic images of RAE in infants, children, or adults. This case report describes and photographically documents classic RAE associated with fatal systemic (paradoxical) air embolism. Complementing postmortem radiography and judicious autopsy techniques, the detection of RAE can aid pathologists in diagnosing systemic air embolism.

Transesophageal echocardiography detection of air embolism during endoscopic surgery and validity of hyperbaric oxygen therapy: Case report

INTRODUCTION

Air embolism has the potential to be serious and fatal. In this paper, we report 3 cases of air embolism associated with endoscopic medical procedures in which the patients were treated with hyperbaric oxygen immediately after diagnosis by transesophageal echocardiography. In addition, we systematically review the risk factors for air embolism, clinical presentation, treatment, and the importance of early hyperbaric oxygen therapy efficacy after recognition of air embolism.

PATIENT CONCERNS

We present 3 patients with varying degrees of air embolism during endoscopic procedures, one of which was fatal, with large amounts of gas visible in the right and left heart chambers and pulmonary artery, 1 showing right heart enlargement with increased pulmonary artery pressure and tricuspid regurgitation, and 1 showing only a small amount of gas images in the heart chambers.

DIAGNOSES

Based on ETCO2 and transesophageal echocardiography (TEE), diagnoses of air embolism were made.

INTERVENTIONS

The patients received symptomatic supportive therapy including CPR, 100% O2 ventilation, cerebral protection, hyperbaric oxygen therapy and rehabilitation.

OUTCOMES

Air embolism can causes respiratory, circulatory and neurological dysfunction. After aggressive treatment, one of the 3 patients died, 1 had permanent visual impairment, and 1 recovered completely without comorbidities.

CONCLUSIONS

While it is common for small amounts of air/air bubbles to enter the circulatory system during endoscopic procedures, life-threatening air embolism is rare. Air embolism can lead to serious consequences, including respiratory, circulatory, and neurological impairment. Therefore, early recognition of severe air embolism and prompt hyperbaric oxygen therapy are essential to avoid its serious complications.

Investigation of air bubble properties: Relevance to prevention of coronary air embolism during cardiac surgery

Although de-airing procedures are commonly performed during cardiac surgery, use of these procedures is not necessarily based on evidence. Uncertainly remains around the size of bubbles that can be detected by echocardiography, whether embolized air or carbon dioxide can be absorbed, and the reasons for embolic events occurring despite extensive de-airing. Since air bubbles are invisible in the blood, we used simple experimental models employing water and 10% dextran solution to determine the correlation between actual bubble size and the depicted size on echocardiography, bubble size, and floatation velocity and the absorption of carbon dioxide under embolization and irrigation conditions. Bubbles depicted as larger than 1 mm were overestimated by echocardiography: the actual size was larger than 0.4 mm in diameter. While bubbles of 0.5 mm had a floatation velocity of 2 to 3 cm/s, the buoyancy of bubbles smaller than 0.3 mm was negligible. Thus, bubbles that are depicted as larger than 1 mm on echocardiography or that present with apparent buoyancy should be visible and need to be meticulously removed. However, echocardiography cannot distinguish bubbles of around 0.1 mm in diameter from those of capillary size (<10 μm). Thus, we advise continuous venting of dense bubbles until they become sparse. While carbon dioxide was rapidly absorbed when circulating, the absorption of embolized carbon dioxide was negligible. These results suggest that detected intracardiac air represents residual "air," with carbon dioxide already absorbed. Therefore, the use of conventional de-airing procedures needs reconsideration: air and buoyant bubbles should be removed from the heart before they are expelled into the aorta; this requires timely and precise assessment with transesophageal echocardiography and effective collaboration between surgeons, anesthesiologists, and perfusionists.

Iatrogenic Pulmonary Air Embolism with Rapid Resolution: A Case Report

BACKGROUND

Iatrogenic pulmonary air embolism is a fairly common and sometimes deadly complication of i.v. contrast injection.

CASE REPORT

We present the case of a 33-year-old man with a symptomatic iatrogenic injection air embolism and resolution within 5 h. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Given the importance of computed tomography imaging in emergency medicine, clinicians should be aware of the risk for injection air embolism from i.v. contrast injection.

Open chest and pericardium facilitate transpulmonary passage of venous air emboli

BACKGROUND

Transpulmonary passage of air emboli can lead to fatal brain- and myocardial infarctions. We studied whether pigs with open chest and pericardium had a greater transpulmonary passage of venous air emboli than pigs with closed thorax.

METHODS

We allocated pigs with verified closed foramen ovale to venous air infusion with either open chest with sternotomy and opening of the pleura and pericardium (n = 8) or closed thorax (n = 16). All pigs received a five-hour intravenous infusion of ambient air, starting at 4-6 mL/kg/h and increased by 2 mL/kg/h each hour. We assessed transpulmonary air passage by transesophageal M-mode echocardiography and present the results as median with inter-quartile range (IQR).

RESULTS

Transpulmonary air passage occurred in all pigs with open chest and pericardium and in nine pigs with closed thorax (56%). Compared to pigs with closed thorax, pigs with open chest and pericardium had a shorter to air passage (10 minutes (5-16) vs. 120 minutes (44-212), P < .0001), a smaller volume of infused air at the time of transpulmonary passage (12 mL (10-23) vs.170 mL (107-494), P < .0001), shorter time to death (122 minutes (48-185) vs 263 minutes (248-300, P = .0005) and a smaller volume of infused air at the time of death (264 mL (53-466) vs 727 mL (564-968), P = .001). In pigs with open chest and, infused air and time to death correlated strongly (r = 0.95, P = .001).

CONCLUSION

Open chest and pericardium facilitated the transpulmonary passage of intravenously infused air in pigs.

Surfactant Attenuates Air Embolism-Induced Lung Injury by Suppressing NKCC1 Expression and NF-κB Activation

Excessive amounts of air can enter the lungs and cause air embolism (AE)-induced acute lung injury (ALI). Pulmonary AE can occur during diving, aviation, and iatrogenic invasive procedures. AE-induced lung injury presents with severe hypoxia, pulmonary hypertension, microvascular hyper-permeability, and severe inflammatory responses. Pulmonary AE-induced ALI is a serious complication resulting in significant morbidity and mortality. Surfactant is abundant in the lungs and its function is to lower surface tension. Earlier studies have explored the beneficial effects of surfactant in ALI; however, none have investigated the role of surfactant in pulmonary AE-induced ALI. Therefore, we conducted this study to determine the effects of surfactant in pulmonary AE-induced ALI. Isolated-perfused rat lungs were used as a model of pulmonary AE. The animals were divided into four groups (n = 6 per group): sham, air embolism (AE), AE + surfactant (0.5 mg/kg), and AE+ surfactant (1 mg/kg). Surfactant pretreatment was administered before the induction of pulmonary AE. Pulmonary AE was induced by the infusion of 0.7 cc air through a pulmonary artery catheter. After induction of air, pulmonary AE was presented with pulmonary edema, pulmonary microvascular hyper-permeability, and lung inflammation with neutrophilic sequestration. Activation of NF-κB was observed, along with increased expression of pro-inflammatory cytokines, and Na-K-Cl cotransporter isoform 1 (NKCC1). Surfactant suppressed the activation of NF-κB and decreased the expression of pro-inflammatory cytokines and NKCC1, thereby attenuating AE-induced lung injury. Therefore, AE-induced ALI presented with pulmonary edema, microvascular hyper-permeability, and lung inflammation. Surfactant suppressed the expressions of NF-κB, pro-inflammatory cytokines, and NKCC1, thereby attenuating AE-induced lung injury.

Massive Air Embolism During Atrial Fibrillation Ablation: Averting Disaster in a Time of Crisis

A 62-year-old male with symptomatic persistent atrial fibrillation underwent radiofrequency catheter ablation. During exchange of the saline irrigation bag, the patient developed sudden hypotension and bradycardia and was found to have a massive air embolism. Air was successfully aspirated with catheters, and the patient did not suffer any permanent sequelae. (Level of Difficulty: Intermediate.)

Iatrogenic air embolism

Air embolism should be treated promptly with high fraction of supplemental oxygen and repositioning to help facilitate reabsorption of the air bubble. Hyperbaric oxygen therapy should be given to those with severe disease.

The Blockade of Store-Operated Calcium Channels Improves Decompression Sickness in Rats

Background

Previous investigations reveal that BTP2, a store-operated calcium channel blocker, has protective and anti-inflammatory properties in multiple inflammatory diseases. This study investigates whether BTP2 can protect against decompression sickness (DCS) in a rat model.

Methods

BTP2 (2 mg/kg) was administered to male Sprague–Dawley rats 30 min before subjecting them to hyperbaric pressure. Control rats were not treated. After decompression, signs of DCS were examined, and samples of bronchoalveolar lavage fluid and lung tissue were obtained for evaluation.

Results

The incidence and mortality of DCS were decreased significantly in rats treated with BTP2 compared to those treated with dimethyl sulfoxide. BTP2 significantly attenuated DCS-induced lung edema, histological evidence of lung inflammation, necroptosis, and apoptosis, while it decreased levels of tumor necrosis factor alpha, interleukin-6, and cytokine-induced neutrophil chemoattractant-1 in bronchoalveolar lavage fluid. In addition, BTP2 reduced the expression of nuclear factor of activated T cells and early growth response protein 3 in lung tissue. BTP2 also significantly increased the levels of inhibitor kappa B alpha and suppressed the levels of nuclear factor kappa B in lung tissue.

Conclusion

The results suggest that BTP2 may has potential as a prophylactic therapy to attenuate DCS-induced injury.

Pulmonary Air embolism Associated with Pneumocephalus: A Case Report

Iatrogenic air embolism is associated with significant morbidity and mortality. Retrograde cerebral venous air embolism is most frequently associated with manipulation of venous access most commonly from central venous catheters. The ascension of air to the cerebral circulation is possibly due to the low specific gravity of air compared to blood and the performance of procedures in the sitting position. Increased right ventricular pressures in the setting of pulmonary thromboembolism may also contribute to the retrograde flow of air. We present the case of a 61-year-old woman who developed a massive pulmonary embolism and pneumocephalus, which was evident during contrast enhanced CT pulmonary angiography. Neurological deficits were not apparent and air resorption occurred after 48 hours of high flow oxygen therapy.

Effective handling of substantial arterial air embolization during extracorporeal perfusion

This report highlights the need for a coordinated approach to substantial arterial air embolization, considering the high risk of neurologic injury. Appropriate management may involve systemic hypothermia, hyperoxia, and retrograde cerebral perfusion.

A retrospective analysis of the risk factors associated with systemic air embolism following percutaneous lung biopsy

In the present study, the risk factors for systemic air embolism as a complication of percutaneous CT-guided lung biopsy were explored. Data from 2,026 percutaneous CT-guided lung biopsy procedures were retrospectively analyzed. All cases were divided into a concurrent air embolism group and a control group, depending on whether air embolism occurred during the puncture process. A systemic air embolism was confirmed when CT values <-200 Hounsfield units were observed in two sequential images. A total of 19 cases (0.9%) of air embolism were detected among the 2,026 patients subjected to percutaneous CT-guided lung biopsy procedures. The most frequently detected embolism site was the left ventricle (89.5%). Only 3 cases (15.8%) were accompanied by obvious clinical symptoms. The results indicated that a puncture location above the level of the left atrium and coughing during the procedure significantly altered the likelihood of embolism developing (P=0.002 and P=0.014 vs. control, respectively). In conclusion, a puncture lesion above the level of the left atrium and coughing during the procedure may be risk factors for air embolism development.

Prevention of serious air embolism during cryoballoon ablation; risk assessment of air intrusion into the sheath by catheter selection and change in intrathoracic pressure: An ex vivo study

INTRODUCTION

One cause of cerebral infarction during cryoballoon ablation is the entry of air into a sheath due to the use of inappropriate catheters. It is known that the left atrial pressure of patients with obstructive sleep apnea syndrome can be negative. However, the effects of catheter selection and negative pressure changes in the sheath on air intrusion are not yet well understood. The aim of this study was to evaluate how catheter selection and negative pressure changes affect air intrusion and to perform countermeasures for air intrusion.

METHODS AND RESULTS

This experiment used siphon principle to create negative pressure in the sheath. Noncryoablation catheters (not designed exclusively for cryoballoon ablation) and cryoballoon catheters were investigated. Catheters were inserted into the sheath and then removed. Thereafter, the amount of air in the sheath was measured. For catheters producing significantly larger amounts of air intrusion, the catheters were inserted via a long sheath in the sheath (sheath-in-sheath technique) and the same procedures were repeated. We found that the amount of air intrusion through most of the noncryoablation catheters was significantly larger than that through cryoablation catheters. An increase in the magnitude of negative pressure in the sheath resulted in a proportional increase in air intrusion, but the sheath-in-sheath technique significantly reduced air intrusion.

CONCLUSION

The amount of air intrusion increased when using catheters with complicated tip shapes and thin outer diameters and when the magnitude of negative pressure in the sheath increased. The sheath-in-sheath technique may be an effective countermeasure.

Prime the Line! A Case Report of Air Embolism from a Peripheral IV Line in the Field

Venous air embolisms are rare but a cause of potentially life-threatening events with associated cardiovascular, pulmonary and neurologic effects. We report the first prehospital case of a venous air embolism in a 31-year-old male who became hemodynamically unstable after a peripheral intravenous catheter with unprimed tubing was placed by paramedics in the prehospital setting and diagnosed in the emergency department. We highlight the clinical presentation, diagnosis and emergency management of venous air embolisms.

A High-pressure Solution for a High-pressure Situation: Management of Cerebral Air Embolism with Hyperbaric Oxygen Therapy

Cerebral air embolism can complicate many medical procedures, including cardiac surgery, venous and arterial access, and laparoscopic surgery. It can be a devastating diagnosis and can cause a life-threatening compromise to the cardiac, respiratory, or cerebrovascular system. It is a rare complication of central venous vascular access manipulation. A cerebral air embolism can lead to acute ischemic and cerebral oedema, which mimics other stroke syndromes, but the acute treatment differs, with prompt administration of hyperbaric oxygen therapy being the mainstay of treatment. A 59-year-old male became acutely unresponsive followed by the emergence of evolving neurology with fixed gaze palsy and a dense 0/5 left-sided hemiparesis. This occurred shortly after a right internal jugular central venous catheter (CVC) was removed (against protocol) during inspiration and sitting upright. Computed tomography (CT) imaging showed air in the right internal jugular vein, as well as intraparenchymal air. Treatment with hyperbaric oxygen was instituted within six hours. There was an excellent recovery of neurologic function, with power improving to 4+/5 over the course of the following week. Clinical staff need to be aware of the policy for central line removal, as well as having a high index of suspicion for air embolism in patients with evolving neurology immediately post-line removal. Early consideration of hyperbaric oxygen can result in improved functional outcomes.

Massive air embolism resulting in ischemic stroke after left ventricular assist device implantation

We present the first case of ischemic stroke secondary to massive air embolus during implantation of a left ventricular assist device (LVAD). The patient experienced a suction event at the time of aortic cannula removal. Despite the use of all standard deairing techniques and flooding the operative field with continuous-flow carbon dioxide, a significant amount of air was delivered into the ascending aorta through the LVAD pump.

Systemic Air Embolism Following Computed Tomography-Guided Lung Biopsy

A 61-year-old male with a history of poorly differentiated squamous cell carcinoma of tongue who completed chemo-radiation was found to have bilateral lung nodules on follow-up positron emission tomography (PET) scan. He underwent computed tomography (CT)-guided lung biopsy. Sequential chest scans done during the procedure showed air-fluid level in the left ventricle, suggestive of air embolism. He was hemodynamically stable during the procedure, however at the end of the procedure he developed right-sided face and arm weakness with aphasia. Emergent CT scans including angiography of head and neck were done which did not show any bleed and was also negative for any air in intracranial vasculature. Patient was treated with 100% oxygen. His neurological symptoms resolved in 30 minutes and he was subsequently admitted to intensive care unit (ICU) for further management. Six hours later, repeat CT of chest was done which showed resolution of air embolism.