[Cerebral gas embolism as a complication of diffuse interstitial lung disease] / Embolismo gaseoso cerebral como complicación de una enfermedad pulmonar intersticial difusa.

Introduction: Cerebral gas embolism is an unusual but extremely serious condition that occurs when air is introduced into the arterial or venous circulation of the brain. Although rare, it can lead to significant neurological deficits and even the death of the patient. Clinical Case: 76-year-old patient with pre-existing diffuse interstitial lung disease, who experienced a massive stroke due to spontaneous pneumomediastinum. Her presentation included confusion, seizures, and motor weakness. Imaging tests revealed air bubbles in the cerebral sulci and hypodense areas in the cerebellum and parietooccipitals. In addition, pneumothorax and air in the upper mediastinum were noted on chest radiographs and chest CT scan. Despite therapeutic measures such as hyperbaric oxygen, the patient unfortunately died due to multiple organ failure. Discussion: The diagnosis of cerebral gas embolism generally involves performing a cerebral computed tomography, which is highly sensitive for detecting the presence of air in the cerebral vessels. Management includes monitoring of vital and neurological signs, as well as specific measures such as airway closure, venous catheter aspiration, Trendelenburg positioning, and hyperbaric oxygen. Conclusion: Cerebral gas embolism is a potentially fatal condition that requires a brain computed tomography for diagnosis and it is vitally important to know the prevention measures to avoid the appearance of this complication and also to know the general measures to adopt when it occurs.

Introducción: La embolia gaseosa cerebral es una afección inusual pero extremadamente grave que se produce cuando se introduce aire en la circulación arterial o venosa del cerebro. Aunque poco común, puede derivar en déficits neurológicos significativos e incluso la muerte del paciente. Caso Clínico: Paciente de 76 años con una enfermedad pulmonar intersticial difusa preexistente, que experimentó un ictus masivo debido a un neumomediastino espontáneo. Su presentación incluyó confusión, convulsiones y debilidad motora. Las pruebas de imagen revelaron burbujas de aire en los surcos cerebrales y áreas hipodensas en el cerebelo y parietooccipitales. Además, se observó neumotórax y aire en el mediastino superior en las radiografías de tórax y la tomografía torácica. A pesar de las medidas terapéuticas como el oxígeno hiperbárico, la paciente lamentablemente falleció debido al fallo multiorgánico. Discusión: El diagnóstico de embolia gaseosa cerebral generalmente implica la realización de una tomografía computarizada cerebral, que es altamente sensible para detectar la presencia de aire en los vasos cerebrales. El manejo incluye el control de las constantes vitales y neurológicas, así como medidas específicas como cierre de la entrada de aire, aspiración de catéteres venosos, posicionamiento de Trendelenburg y oxígeno hiperbárico. Conclusión: La embolia gaseosa cerebral es una afección potencialmente mortal que requiere una tomografía computarizada cerebral para el diagnóstico y de vital importancia conocer las medidas de prevención para evitar la aparición de esta complicación y así mismo conocer las medidas generales a adoptar cuando ésta se presenta.

Can Intracardiac Echocardiography Reduce Steam Pops During Half-Normal Saline Irrigated Radiofrequency Ablation?

BACKGROUND: Irrigated radiofrequency ablation with half-normal saline can potentially increase lesion size but may increase the risk of steam pops with the risk of emboli or perforation. We hypothesized that pops would be preceded by intracardiac echocardiography (ICE) findings as well as a large impedance fall. METHODS: In 100 consecutive patients undergoing endocardial ventricular arrhythmia radiofrequency ablation with half-normal saline, we attempted to observe the ablation site with ICE. Radiofrequency ablation power was titrated to a 15 to 20 Ohm impedance fall and could be adjusted for tissue whitening and increasing bubble formation on ICE. Steam pops were defined as audible or a sudden explosion of microbubbles on ICE. RESULTS: Of 2190 ablation applications in 100 patients (82% cardiomyopathy, 50% sustained ventricular tachycardia), pops occurred during 43 (2.0%) applications. Sites with pops had greater impedance decreases of 18 [14, 21]% versus 13 [10, 17]% (P<0.001). ICE visualized 1308 (59.7%) radiofrequency sites, and fewer pops occurred when ICE visualized the radiofrequency ablation site (1.4%) compared with without ICE visualization (2.8%; P=0.016). Of the 18 ICE-visible pops, 7 (39%) were silent but recognized as an explosion of bubbles on ICE. With ICE, 89% of pops were preceded by either tissue whitening or a sudden increase in bubbles. In a multivariable model, tissue whitening and a sudden increase in bubbles were associated with steam pops (odds ratio, 7.186; P=0.004, and odds ratio, 29.93; P<0.001, respectively), independent of impedance fall and power. There were no pericardial effusions or embolic events with steam pops. CONCLUSIONS: Steam pops occurred in 2% of half-normal saline radiofrequency applications titrated to an impedance fall and are likely under-recognized without ICE. On ICE, steam pops are usually preceded by tissue whitening or a sudden increase in bubble formation, which can potentially be used to adjust radiofrequency application to help reduce pops.

In-field use of I-VED electrical impedance sensor for assessing post-dive decompression stress in humans.

Purpose: Ultrasound imaging is commonly used in decompression research to assess venous gas emboli (VGE) post-dive, with higher loads associated with increased decompression sickness risk. This work examines, for the first time in humans, the performance of a novel electrical impedance spectroscopy technology (I-VED), on possible detection of post-dive bubbles presence and arterial endothelial dysfunction that may be used as markers of decompression stress. Methods: I-VED signals were recorded in scuba divers who performed standardized pool dives before and at set time points after their dives at 35-minute intervals for about two hours. Two distinct frequency components of the obtained signals, Low-Pass Frequency-LPF: 0-0.5 Hz and Band-Pass Frequency-BPF: 0.5-10 Hz, are extracted and respectively compared to VGE presence and known flow-mediated dilation trends for the same dive profile for endothelial dysfunction. Results: Subjects with VGE counts above the median for all subjects were found to have an elevated average LPF compared to subjects with lower VGE counts, although this was not statistically significant (p=0.06), as well as significantly decreased BPF standard deviation post-dive compared to pre-dive (p=0.008). Conclusions: I-VED was used for the first time in humans and operated to provide qualitative in-vivo electrical impedance measurements that may contribute to the assessment of decompression stress. Compared to ultrasound imaging, the proposed method is less expensive, not operator-dependent and compatible with continuous monitoring and application of multiple probes. This study provided preliminary insights; further calibration and validation are necessary to determine I-VED sensitivity and specificity.

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.

Secondary deterioration in a patient with cerebral and coronary arterial gas embolism after brief symptom resolution: a case report.

Introduction: Hyperbaric oxygen treatment (HBOT) is recommended for arterial gas embolism (AGE) with severe symptoms. However, once symptoms subside, there may be a dilemma to treat or not. Case presentation: A 71-year-old man was noted to have a mass shadow in his left lung, and a transbronchial biopsy was performed with sedation. Flumazenil was intravenously administered at the end of the procedure. However, the patient remained comatose and developed bradycardia, hypotension, and ST-segment elevation in lead II. Although the ST changes spontaneously resolved, the patient had prolonged disorientation. Whole- body computed tomography revealed several black rounded lucencies in the left ventricle and brain, confirming AGE. The patient received oxygen and remained supine. His neurological symptoms gradually improved but worsened again, necessitating HBOT. HBOT was performed seven times, after which neurological symptoms resolved almost completely. Conclusions: AGE can secondarily deteriorate after symptoms have subsided. We recommend that HBOT be performed promptly once severe symptoms appear, even if they resolve spontaneously.

Chemotherapy-induced pneumatosis intestinalis followed by hepatic portal venous gas. A case report.

Pneumatosis intestinalis (PI) is a rare disease, and there are many theories about its pathogenesis. Hepatic portal venous gas (HPVG), is thought to occur secondary to intramural intestinal gas emboli migrating through the portal venous system via the mesenteric veins. PI accompanied by HPVG is usually a sign of bowel ischaemia and is associated with a high mortality rate. We report here, a patient with liver metastases from colorectal cancer who developed PI followed by HPVG after treatment with 5-Fluorouracil, leucovorin, and oxaliplatin (mFOLFOX6). Timely attention and management of gastrointestinal symptoms following chemotherapy are essential in the treatment of this type of patient.

[A case of hepatic portal venous gas and upper gastrointestinal mucosal injury due to accidental ingestion of hydrogen peroxide].

A 40-year-old woman was admitted to our hospital by ambulance due to accidental ingestion of 100ml of 35% hydrogen peroxide. Although the patient suffered from frequent vomiting, abdominal distension, and abdominal pain, signs of peritonitis were not observed. An abdominal computed tomography examination demonstrated obvious gas images in the gastric wall and intrahepatic portal veins. Upper gastrointestinal endoscopy revealed mucosal redness, swelling, and erosion from the lower part of the esophagus to the duodenum. Portal venous gas and upper gastrointestinal mucosal injury due to accidental hydrogen peroxide ingestion were suspected. As the vital signs were stable and there were no signs peritoneal irritation or neurological symptoms, she was treated medically with vonoprazan, rebamipide, and sodium alginate. The next day, abdominal symptoms immediately improved and 3 days later, hepatic portal venous gas had disappeared on ultrasonography. She was discharged on the 5th day after admission. Two months later, upper gastrointestinal endoscopy showed improvement in inflammatory findings. We report a remarkable case of hepatic portal venous gas and upper gastrointestinal mucosal injury and elucidate the endoscopic findings associated with hydrogen peroxide ingestion.

Intraoperative vascular air embolism and intracardiac thrombosis complicating liver transplantation: a case report.

BACKGROUND: Intracardiac thrombus and vascular air embolism represent rare complications in the context of orthotopic liver transplantation. While isolated reports exist for intracardiac thrombus and vascular air embolism during orthotopic liver transplantation, this report presents the first documentation of their simultaneous occurrence in this surgical setting. CASE PRESENTATION: This case report outlines the clinical course of a 60-year-old white female patient with end-stage liver disease complicated by portal hypertension, ascites, and hepatocellular carcinoma. The patient underwent orthotopic liver transplantation and encountered concurrent intraoperative complications involving intracardiac thrombus and vascular air embolism. Transesophageal echocardiography revealed the presence of air in the left ventricle and a thrombus in the right atrium and ventricle. Successful management ensued, incorporating hemodynamic support, anticoagulation, and thrombolytic therapy, culminating in the patient's discharge after a week. CONCLUSIONS: This report highlights the potential for simultaneous intraoperative complications during orthotopic liver transplantation, manifesting at any phase of the surgery. It underscores the critical importance of vigilant monitoring throughout orthotopic liver transplantation to promptly identify and effectively address these rare yet potentially catastrophic complications.

Fatal cardiac air embolism after CT-guided percutaneous needle lung biopsy: medical complication or medical malpractice?

Computed tomography (CT)-guided percutaneous needle biopsy of the lung is a well-recognized and relatively safe diagnostic procedure for suspicious lung masses. Systemic air embolism (SAE) is a rare complication of transthoracic percutaneous lung biopsies. Herein, we present a case of an 81-year-old man who underwent CT-guided percutaneous needle biopsy of a suspicious nodule in the lower lobe of the right lung. Shortly after the procedure, the patient coughed up blood which prompted repeat CT imaging. He was found to have a massive cardiac air embolism. The patient became unresponsive and, despite resuscitation efforts, was pronounced dead. The pathophysiology, risk factors, clinical features, radiological evidence, and autopsy findings associated with SAE are discussed, which may, in light of the current literature, assist with the dilemma between assessing procedural complications and medical liability. Given the instances of SAE in the setting of long operative procedures despite careful technical execution, providing accurate and in-depth information, including procedure-related risks, even the rarest but potentially fatal ones, is recommended for informed consent to reduce medicolegal litigation issues.

Commentary on "Fatal cardiac air embolism after CT-guided percutaneous needle lung biopsy: medical complication or medical malpractice?"

To differentiate between medical malpractice and expected, but rare, medical complication in a medicolegal autopsy context is often difficult. Such an assessment requires knowledge about the clinical practice associated with the procedure at hand, and that findings of the autopsy, including medical relevant information such as patient chart, radiological imaging, and statements from witnesses about the medical procedure itself, provides evidence that substantiate either conclusion. In a case report published in the journal such an assessment is discussed by presenting findings and circumstances surrounding the death of a patient during a percutaneous needle lung biopsy procedure. The authors conclude that the death was not due to medical malpractice. However, in this commentary it is highlighted that the reasoning behind the conclusion needs to be further substantiated.

Computer tomography perfusion patterns in iatrogenic cerebral arterial gas embolism: A retrospective cohort study.

PURPOSE: Cerebral arterial gas embolism (CAGE) occurs when air or medical gas enters the systemic circulation during invasive procedures and lodges in the cerebral vasculature. Non-contrast computer tomography (CT) may not always show intracerebral gas. CT perfusion (CTP) might be a useful adjunct for diagnosing CAGE in these patients. METHODS: This is a retrospective single-center cohort study. We included patients who were diagnosed with iatrogenic CAGE and underwent CTP within 24 h after onset of symptoms between January 2016 and October 2022. All imaging studies were evaluated by two independent radiologists. CTP studies were scored semi-quantitatively for perfusion abnormalities (normal, minimal, moderate, severe) in the following parameters: cerebral blood flow, cerebral blood volume, time-to-drain and time-to-maximum. RESULTS: Among 27 patient admitted with iatrogenic CAGE, 15 patients underwent CTP within the designated timeframe and were included for imaging analysis. CTP showed perfusion deficits in all patients except one. The affected areas on CTP scans were in general located bilaterally and frontoparietally. The typical pattern of CTP abnormalities in these areas was hypoperfusion with an increased time-to-drain and time-to-maximum, and a corresponding minimal decrease in cerebral blood flow. Cerebral blood volume was mostly unaffected. CONCLUSION: CTP may show specific perfusion defects in patients with a clinical diagnosis of CAGE. This suggests that CTP may be supportive in diagnosing CAGE in cases where no intracerebral gas is seen on non-contrast CT.