Cerebral air embolism after removal of central venous catheter (CVC) is a rare complication but can lead to fatal outcomes. We report a rare case of both cerebral venous and arterial embolism occurring in a patient with underlying scleroderma-related interstitial lung disease (SSc-ILD) and pulmonary hypertension following removal of percutaneous introducer sheath for pulmonary artery catheterization. We discuss the mechanisms, pathophysiology, management and prevention of cerebral air embolism.

BACKGROUND: The semi-sitting position offers advantages for surgeries in the posterior cranial fossa. However, data on its safety and effectiveness for clipping aneurysms in the posterior cerebral circulation are limited. This retrospective cohort study evaluates the safety and effectiveness of using the semi-sitting position for these surgeries.
METHODS: We conducted a retrospective study of 17 patients with posterior cerebral circulation aneurysms who underwent surgical clipping in the semi-sitting position in the Department of Neurosurgery at Hannover Medical School over a 10-year period.
RESULTS: The mean age at surgery was 62 years (range, 31 to 75). Fourteen patients were admitted with subarachnoid hemorrhage and 3 patients had incidental aneurysmas. Fifteen patients had PICA aneurysms, and two had aneurysms of the vertebral artery and the superior cerebellar artery, respectively. The median diameter of the aneurysms was 5 mm (range 3-17 mm). Intraoperative venous air embolism (VAE) occurred in 4 patients, without affecting the surgical or clinical course. VAE was associated with a mild decrease of EtCO2 levels in 3 patients and in 2 patients a decrease of blood pressure occurred which was managed effectively. Surgical procedures proceeded as planned in all instances. There were no complications secondary to VAE. Two patients died secondary to respiratory problems (not related to VAE), and one patient was lost to follow-up. Eleven of fourteen patients were partially or completely independent (Barthel index between 60 and 100) at a median follow-up duration of 13.5 months (range, 3-103 months).
CONCLUSIONS: The semi-sitting position is a safe and effective technique for the surgical clipping of aneurysms in the posterior cerebral circulation. The incidence of VAE is comparable to that seen in tumor surgery. However, it is crucial for the surgical and anesthesiological team to be familiar with potential complications and to react immediately in case of an occurrence of VAE.

BACKGROUND: Venous air embolism (VAE) is a potentially lethal condition, with a reported incidence rate of about 0.13%, and the true incidence may be higher since many VAE are asymptomatic. The current treatments for VAE include Durant\'s maneuver, aspiration and removal of air through venous catheters, and hyperbaric oxygen therapy. For critically ill patients, use of cardiotonic drugs and chest compressions remain useful strategies. The wider availability of extracorporeal membrane oxygenation (ECMO) has brought a new option for VAE patients.
METHODS: A 53-year-old female patient with VAE presented to the emergency clinic due to abdominal pain with fever for 1 d and unconsciousness for 2 h. One day ago, the patient suffered from abdominal pain, fever, and diarrhea. She suddenly became unconscious after going to the toilet during the intravenous infusion of ciprofloxacin 2 h ago, accompanied by nausea and vomiting, during which a small amount of gastric contents were discharged. She was immediately sent to a local hospital, where cranial and chest computed tomography showed bilateral pneumonia as well as accumulated air visible in the right ventricle and pulmonary artery. The condition deteriorated despite endotracheal intubation, rehydration, and other treatments, and the patient was then transferred to our hospital. Veno-arterial ECMO was applied in our hospital, and the patient\'s condition gradually improved. The patient was successfully weaned from ECMO and extubated after two days.
CONCLUSIONS: ECMO may be an important treatment for patients with VAE in critical condition.

Venous air embolism (VAE) represents a rare yet potentially life-threatening complication encountered during neurosurgical procedures, particularly craniotomy. Here, we present a case of a 30-year-old male undergoing excision of a cerebellar abscess who developed VAE midway through the procedure. Immediate recognition and intervention were paramount in managing the embolism effectively, ensuring a favorable surgical outcome. Vigilant monitoring, prompt cessation of the procedure, and implementation of preventive measures such as oxygen therapy and venous air aspiration were pivotal in mitigating the embolism\'s effects. This study underscores the critical importance of intraoperative vigilance, preparedness, and multidisciplinary teamwork in addressing rare but potentially catastrophic complications during neurosurgical interventions.

BACKGROUND: Venous air embolism (VAE) consists of air entering vascular structures due to a pressure gradient generated during medical-surgical procedures. Most cases of VAE are iatrogenic.
METHODS: Three hospitalised patients aged 23 to 86 years underwent venous air embolism (VAE) in the right heart system after performing CTPA. One of the patients died from a complication of venous thromboembolic disease (PE, coronary sinus thrombosis, mesenteric venous thrombosis).
CONCLUSIONS: CTPA is a procedure that a priori seems innocuous, but it can be a potential cause of death or serious consequences for patients undergoing radiological procedures where the administration of contrast and the use of an injector could be counterproductive. Radiologists and physicians responsible for the patient should be aware of vascular gas embolism after contrast injection in patients undergoing CTPA.

To analyze the primary complications related to semisitting position in patients undergoing cerebelo-pontine angle surgery.
Retrospective data analysis from patients undergoing elective tumoral cerebelo-pontine angle surgery in a semisitting position. The incidence, severity, occurrence moment, treatment, duration, and outcomes of venous air embolism (VAE), pneumocephalus, postural hypotension, and other complications were recorded. Neurointensive care unit (NICU), length of stay (LOS), hospital LOS, and modified Rankin scale scores were calculated six months after surgery.
Fifty patients were operated on. Eleven (22%) presented VAE (mean duration 8±4.5min): five (10%) during tumor resection, and four (8%) during dural opening. Ten (20%) were resolved by covering the surgical bed, air bubbles aspiration, jugular compression, and one (2%) tilted to a steep Trendelenburg position. One (2%) had intraoperative hemodynamic instability. The only variable associated with VAE was meningioma at histopathology OR=4.58, p=0.001. NICU was higher in patients with VAE (5.5±1.06 vs. 1.9±0.20 days, p=0.01). There were no differences in the Rankin scale. All patients presented postoperative pneumocephalus with a good level of consciousness, except one (2%) who required evacuation. Seven patients (14%) showed postural hypotension, three (6%) after positioning, and one (2%) after developing a VAE; all were reversed with usual vasoactive drugs. No other position-related complications or mortality were registered in this series.
The semisitting position is a safe option with the knowledge, prevention, detection, and early solution of all the possible complications. The development of VAE rarely implies hemodynamic instability or greater disability after surgery. Postoperative pneumocephalus is very common and rarely requires evacuation. Excellent cooperation between anesthesia, nursing, neurophysiology, and neurosurgery teams is essential to manage complications.

Venous air embolism (VAE) is a rare but potentially lethal condition. It has numerous clinical and physiological causes. We present a case report of a 72-year-old Saudi male, known case of diabetes mellitus (DM), hypertension, and ischemic heart disease. The patient came to the emergency room (ER) complaining of the heaviness of the tongue that resolved spontaneously within a few hours. He underwent percutaneous coronary angiography three months ago. The patient with the previously mentioned neurological symptoms, who had been misdiagnosed as having transient cerebral ischemia, was, after a computerized tomography (CT) scan result, diagnosed with venous air embolism. Venous air embolism can occur in situations other than those in which patients are traditionally thought to be at risk, making diagnosis difficult. Any sudden change in mental status and hemodynamic alterations during minimally invasive procedures should raise the physician\'s suspicion of VAE. Because VAE is an uncommon complication, few cases have been recorded in Saudi Arabia.

UNASSIGNED: Patient positioning is a matter of ongoing debate in the surgical treatment of vestibular schwannoma (VS). Main endpoints of this discussion are preservation of facial nerve functioning, extent of resection, and complications. In this meta-analysis, we aim to investigate the impact of patient positioning on VS surgery via the retrosigmoid approach.
UNASSIGNED: We searched for eligible comparative trials on PubMed, Cochrane library, and Web of Science. Positioning groups were compared regarding facial nerve outcome, extent of resection, postoperative hydrocephalus, postoperative CSF leaks, perioperative venous air embolism, and perioperative mortality. Two groups of positions were defined, and the following positions were allocated to those groups: (1) Semi-sitting and Sitting-position; (2) Lateral position, supine position with extensive head rotation, lateral oblique (=Fukushima/Three-quarter prone), and park-bench position.
UNASSIGNED: From 374 full-text screenings, 7 studies met the criteria and were included in our meta-analysis comprising 1640 patients. Our results demonstrate a significantly better long-term (≥6 months) outcome of the facial nerve after VS surgery in the semi-sitting positioning (OR: 1.49, 95%CI: 1.03-2.15, p = 0.03). Positioning did not influence the extent of resection, rate of postoperative CSF leaks, and the presence of a postoperative hydrocephalus. Overall incidence of venous air embolisms was significantly associated with VS surgery in sitting positioning (OR: 6.77, 95% CI: 3.66-12.54, p < 0.00001). Perioperative mortality was equal among both positioning groups.
UNASSIGNED: Semi-sitting positioning seems to be associated with an improved facial nerve outcome after VS surgery via the retrosigmoid approach. Venous air embolisms are significantly more often observed among VS patients who underwent surgery in the sitting position, but the perioperative mortality is equal in both positioning groups. Both positioning groups are a safe procedure. Multicentric prospective randomized trials are needed to evaluate the risk-benefit ratio of each positioning in VS surgery via the retrosigmoid approach.

UNASSIGNED: Venous air embolism (VAE) is a life-threatening event characterized as a series of clinical features of the disease caused by gas entering the venous circulation in the body.
UNASSIGNED: A 72-year-old male patient with an ankle fracture after trauma was admitted, and complained of chest pain and dyspnea after the ankle fracture resection and internal fixation. His heart rate and blood pressure dropped, and the patient was diagnosed with VAE according to a chest x-ray and clinical features. Cardiopulmonary resuscitation was carried out and the patient\'s heartbeat recovered; his blood pressure rose to a normal level. The patient was still unconscious and sent to the intensive care unit for continued monitoring and treatment. Unfortunately, the patient discharged himself from the hospital and died 24 h later.
UNASSIGNED: This case suggests that x-ray may be a potential method for the rapid diagnosis of VAE in a resource-limited setting.

Background It has been shown that the incidence of venous air embolism and venous carbon dioxide (CO2) embolism is high during endoscopic retrograde cholangiopancreatography (ERCP). We examined insufflating gas flow and maximum pressure produced by three types of commonly used endoscopes because we could not readily locate technical data for endoscope gas flow and maximum emitted pressure in the manufacturer\'s manuals. Methods We tested the Olympus GIF-Q180 used for esophagogastroduodenoscopy, the CF-Q180 used for colonoscopy, and the TJF-Q180 used for ERCP (Olympus America Inc., Center Valley, Pennsylvania). Under three different clinical gas insufflation scenarios, we measured in vitro maximum gas pressure transduced from a closed space created at the endoscope tip in a worst-case scenario analysis. Results We showed that it is readily possible to generate a pressure (>5-30 times normal central venous pressure) in the air space at the tip of all three endoscopes when insufflation is activated and the gas egress is limited. Conclusions These findings shed additional light on in vivo occurrences of gas embolism during gastrointestinal endoscopy. We postulate that in addition to using exclusively CO2 as the insufflating gas, the risk of gas embolism can be further diminished by regulating insufflating gas pressure at the tip of endoscopes.