Veno-arterial extracorporeal membrane oxygenation for the treatment of obstructive shock caused by venous air embolism:A case report

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.CASE SUMMARY 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.CONCLUSION ECMO may be an important treatment for patients with VAE in critical condition.

Systemic air embolism after transthoracic lung biopsy: A case report and review of literature

Computed tomography (CT)-guided lung biopsy is a common diagnostic procedure that is associated with various complications, including pneumothorax, hemoptysis and parenchymal hemorrhage. Systemic air embolism is a very rare (0.07%) but potentially lifethreatening complication. We report a fatal case of air embolism to the cerebral and coronary arteries confirmed by head and chest CT, followed by a review of the literature.

Air embolism complicating gastrointestinal endoscopy: A systematic review

Gastrointestinal endoscopy has become an important modality for the diagnosis and treatment of various gastrointestinal disorders. One of its major advantages is that it is minimally invasive and has an excellent safety record. Nevertheless, some complications do occur, and endoscopists are well aware and prepared to deal with the commonly recognized ones including bleeding, perforation, infection, and adverse effects from the sedative medications. Air embolism is a very rare endoscopic complication but possesses the poten-tial to be severe and fatal. It can present with cardio-pulmonary instability and neurologic symptoms. The diagnosis may be difficult because of its clinical presen-tation, which can overlap with sedation-related cardio-pulmonary problems or neurologic symptoms possibly attributed to an ischemic or hemorrhagic central nervous system event. Increased awareness is essential for prompt recognition of the air embolism, which can allow potentially life-saving therapy to be provided.Therefore, we wanted to review the risk factors, the clinical presentation, and the therapy of an air embolism from the perspective of the practicing endoscopist.

Fatal left atrial air embolism as a complication of percutaneous transthoracic lung biopsy:A case report

BACKGROUND Computed tomography(CT)-guided percutaneous lung biopsy is a common protocol in the context of diagnostic thoracic oncology,but entails a risk of complications including systematic air embolism(SAE).While SAE is often well tolerated,it can be difficult to treat and may result in rapid mortality in some cases.CASE SUMMARY We report a rare case of left atrial SAE in a 71-year-old woman who underwent a CT-guided lung biopsy of a pulmonary nodule in the posterior basal segment of the right lower lobe.Shortly following needle extraction,she experienced a mild cough,hemoptysis,rapid-onset unconsciousness,and cardiopulmonary arrest.Cardiopulmonary resuscitation was immediately performed,but the patient died 40 min after the procedure.A closer review of collected CT scans revealed the presence of a large volume of air within the left atrium.CONCLUSION Although SAE is generally well tolerated and asymptomatic,interventional radiologists must be aware of the risk of fatal outcomes and establish appropriate emergency management protocols.In this report,the characteristics,mechanisms,and treatment recommendations associated with SAE are discussed in an effort to improve the survival of affected patients.

Suspected cerebrovascular air embolism during endoscopic esophageal varices ligation under sedation with fatal outcome: A case report

BACKGROUND Air embolism is a very rare,yet serious and potentially fatal complication of digestive endoscopic treatment.Air embolism is the result of air directly entering the arteries or veins.However,to recognize neurological dysfunction under sedation can be difficult.Therefore,it is extremely important to identify high-risk groups and take preventive measures.CASE SUMMARY Herein,we report a 74-year-old female patient with esophageal varices who suffered from consciousness disturbance after the third endoscopic ligation of esophageal varices under sedation.Combined with the patient’s imaging examination results and medical history,we highly suspected that the patient had developed paradoxical cerebral air embolism during endoscopic ligation.We learned that the patient died at a later follow-up.In order to be able to identify and prevent the occurrence of air embolism early,we summarize and analyze the risk factors,pathogenesis,clinical manifestations,prevention and treatment options of gastrointestinal endoscopy complicated by cerebral air embolism.CONCLUSION Electroencephalographic monitoring helps to recognize the occurrence of air embolism in time and increase the patient's chance of survival.

Unexpected complication during extracorporeal membrane oxygenation support: Ventilator associated systemic air embolism

Systemic air embolism through a bronchovenous fistu-la(BVF) has been described in patients undergoing positive-pressure ventilation. However, no report has mentioned the potential risks of systemic air embolism through a BVF in patients undergoing extracorporeal membrane oxygenation(ECMO). Positive-pressure ventilation and ECMO support in patients with lung injury can increase the risk of systemic air embolism through a BVF. Increased alveolar pressure, decreased pulmonary venous pressure, and anticoagulation are thought to be the factors that contribute to this complication. Here, we present a case of systemic air embolism in a patient with ECMO and mechanical ventilator support.

Successful treatment of intracardiac air embolism using intracardiac catheter aspiration

Intracardic air embolism is uncommon, however it is a serious condition which frequently leads to catastrophic complications during or after invasive procedures resulting in significant morbidity and mortality. For a successful re- suscitation of patients with intracardiac air embolism, hy- perbaric oxygen therapy is critical.~~2~ Still, due to a hyper- baric chamber＇s unavailability at many hospitals and con- cerns about patient movement resulting in further embolism during transport, such treatment method is gradually dimin- ishing.

Right Hemisphere Cerebral Infarction Due to Air Embolism from Percutaneous Lung Biopsy: A Case Report

Percutaneous transthoracic needle biopsy is a common procedure in interventional radiology. Systemic arterial air embolism causing cerebral infarction is a rare but much feared complication of percutaneous lung biopsy. We present a comprehensive review of iatrogenic air embolism post-lung biopsy, a complication that is often sub optimally managed. Patho-physiology, clinical features, and risk factors and management are reviewed.

Fatal air embolism during endoscopic retrograde cholangio-pancreatography (ERCP): a case report

A 61-year-old woman was diagnosed with common bile duct stones and acute biliary pancreatitis. She had previously undergone cholecystectomy 5 years ago. A planed endoscopic retrograde cholangio-pancreatography (ERCP) was arranged under general anesthesia. The patient was posed at prone position without bronchial intubation. Endoscopic access was achieved smoothly and cholangiography revealed mild dilation of the extrahepatic bile duct with mild graduate taper at ampullary region. Some filling defects were found inside lower CBD. A moderate sphincterotomy was made unremarkably, and some tiny stones were retrieved using a Dormia basket. A retrieval balloon was advanced into bile duct to make occlusion cholangiogram. At this moment, the endoscope lost its location into part one of duodenum. When the scope reaches back to descending duodenum, active bleeding was found coming out from orifice of papilla, accompanied with decreased oxygen saturation and arrhythmia. X-ray examination demonstrated gas within hepatic vein and inferior cava vein, although no free gas was observed in the renal region or subphrenic area. The endoscope was removed immediatelyand patient was changed to supine position. Vigorous cardiopulmonary resuscitation was begun immediately, unfortunately the patient did not response to all the efforts. The causes of death were thought to be systemic air embolism with cardiopulmonary failure.

Cerebral air embolism complicating transbronchial lung biopsy: A case report

BACKGROUND In this case report we describe an extremely rare case of cerebral air embolism following transbronchial lung biopsy(TBLB).Only a few cases of this rare complication were described previously.Every bronchologist should recognize this severe adverse event.Prompt recognition of this complication is mandatory in order to initiate supportive measures and consider hyperbaric oxygen therapy.CASE SUMMARY In this case report we describe an extremely rare case of cerebral air embolism following TBLB.Only a few cases of this rare complication were described previously.Our patient had an incidental finding of lung tumour and pulmonary emphysema.Cerebral air embolism developed during bronchoscopy procedure,immediately after the third trans-bronchial lung biopsy sample and caused cerebral ischaemia of the right hemisphere and severe left-sided hemiplegia.Despite timely initiation of hyperbaric oxygen therapy hemiplegia didn´t resolve and the patient died several weeks later.Cerebral air embolism is an extremely rare complication of TBLB.This condition should be considered in case the patient remains unresponsive or presents with acute neurological symptoms in the postintervention period since early recognition,diagnosis and hyperbaric oxygen therapy initiation are key factors determining the patient´s outcome.CONCLUSION Within this report,we conclude that air/gas embolism is an extremely rare complication after TBLB,which should be considered in case the patient remains unresponsive or presents with acute neurological symptoms in the postintervention period after bronchoscopy.The current gold standard for diagnosis is computed tomography scan of the head.After recognition of this complication we suggest immediate hyperbaric oxygen therapy,if available.

Mapping Air Quality Using Remote Sensing Technology: A Case Study of Nairobi County

Nairobi County experiences rapid industrialization and urbanization that contributes to the deteriorating state of air quality, posing a potential health risk to its growing population. Currently, in Nairobi County, most air quality monitoring stations use low-cost, inaccurate monitors prone to defects. The study’s objective was to map Nairobi County’s air quality using freely available remotely sensed imagery. The Air Pollution Index (API) formula was used to characterize the air quality from cloud-free Landsat satellite images i.e., Landsat 5 TM, Landsat 7 ETM+, and Landsat 8 OLI from Google Earth Engine. The API values were computed based on vegetation indices namely NDVI, TVI, DVI, and the SWIR1 and NIR bands on the QGIS platform. Qualitative accuracy assessment was done using sample points drawn from residential, industrial, green spaces, and traffic hotspot categories, based on a passive-random sampling technique. In this study, Landsat 5 API imagery for 2010 provided a reliable representation of local conditions but indicated significant pollution in green spaces, with recorded values ranging from -143 to 334. The study found that Landsat 7 API imagery in 2002 showed expected results with the range of values being -55 to 287, while Landsat 8 indicated high pollution levels in Nairobi. The results emphasized the importance of air quality factors in API calibration and the unmatched spatial coverage of satellite observations over ground-based monitoring techniques. The study recommends the recalibration of the API formula for characteristic regions, exploring newer satellite sensors like those onboard Landsat 9 and Sentinel 2, and involving key stakeholders in a discourse to develop a suitable Kenyan air quality index.

Study of three-dimensional spatial diffuse discharge in contact electrode structure applied to air purification

In this work,based on the role of pre-ionization of the non-uniform electric field and its effect of reducing the collisional ionization coefficient,a diffuse dielectric barrier discharge plasma is formed in the open space outside the electrode structure at a lower voltage by constructing a three-dimensional non-uniform spatial electric field using a contact electrode structure.The air purification study is also carried out.Firstly,a contact electrode structure is constructed using a three-dimensional wire electrode.The distribution characteristics of the spatial electric field formed by this electrode structure are analyzed,and the effects of the non-uniform electric field and the different angles of the vertical wire on the generation of three-dimensional spatial diffuse discharge are investigated.Secondly,the copper foam contact electrode structure is constructed using copper foam material,and the effects of different mesh sizes on the electric field distribution are analyzed.The results show that as the mesh size of the copper foam becomes larger,a strong electric field region exists not only on the surface of the insulating layer,but also on the surface of the vertical wires inside the copper foam,i.e.,the strong electric field region shows a three-dimensional distribution.Besides,as the mesh size increases,the area of the vertical strong electric field also increases.However,the electric field strength on the surface of the insulating layer gradually decreases.Therefore,the appropriate mesh size can effectively increase the discharge area,which is conducive to improving the air purification efficiency.Finally,a highly permeable stacked electrode structure of multilayer wire-copper foam is designed.In combination with an ozone treatment catalyst,an air purification device is fabricated,and the air purification experiment is carried out.

Fluid-chemical modeling of the near-cathode sheath formation process in a high current broken in DC air circuit breaker

When the contacts of a medium-voltage DC air circuit breaker(DCCB) are separated, the energy distribution of the arc is determined by the formation process of the near-electrode sheath. Therefore, the voltage drop through the near-electrode sheath is an important means to build up the arc voltage, which directly determines the current-limiting performance of the DCCB. A numerical model to describe the near-electrode sheath formation process can provide insight into the physical mechanism of the arc formation, and thus provide a method for arc energy regulation. In this work, we establish a two-dimensional axisymmetric time-varying model of a medium-voltage DCCB arc when interrupted by high current based on a fluid-chemical model involving 16 kinds of species and 46 collision reactions. The transient distributions of electron number density, positive and negative ion number density, net space charge density, axial electric field, axial potential between electrodes, and near-cathode sheath are obtained from the numerical model. The computational results show that the electron density in the arc column increases, then decreases, and then stabilizes during the near-cathode sheath formation process, and the arc column's diameter gradually becomes wider. The 11.14 V–12.33 V drops along the17 μm space charge layer away from the cathode(65.5 k V/m–72.5 k V/m) when the current varies from 20 k A–80 k A.The homogeneous external magnetic field has little effect on the distribution of particles in the near-cathode sheath core,but the electron number density at the near-cathode sheath periphery can increase as the magnetic field increases and the homogeneous external magnetic field will lead to arc diffusion. The validity of the numerical model can be proven by comparison with the experiment.

Cronkhite-Canada syndrome complicated with pulmonary embolism:A case report

BACKGROUND Cronkhite-Canada syndrome(CCS)is a rare disease,that causes gastrointestinal polyps,ectodermal abnormalities,and gastrointestinal symptoms.CCS is prone to thromboembolism,but clinical workers have not yet established a clinical consciousness of preventing thromboembolism.The present case illustrates pulmonary embolism(PE)complicated by CCS.CASE SUMMARY A 46-year-old male patient presented with mucus,purulent,and bloody stool.Ectodermal changes included skin pigmentation,alopecia,and nail dystrophy.Colonoscopy revealed the presence of multiple polyps.After a comprehensive evaluation,the patient was diagnosed with CCS.During the disease,he was also diagnosed with pulmonary embolism,Riehl's melanosis,and intestinal flora imbalance.After symptomatic treatment with omeprazole,mesalazine,rivaroxaban,nutritional support,and regulation of intestinal flora,the patient’s symptoms were significantly relieved.CONCLUSION CCS complicated with PE was reported for the first time in China in this study.Despite the fact that CCS is extremely rare,patients with CCS should be classified as a high-risk venous thromboembolism(VTE)population,and emphasis should be placed on venous thromboembolism risk assessment and stratification,deep venous thromboembolism screening,prevention of VTE,and careful long-term follow-up.

Recent progress of self-supported air electrodes for flexible Zn-air batteries

Smart wearable devices are regarded to be the next prevailing technology product after smartphones and smart homes,and thus there has recently been rapid development in flexible electronic energy storage devices.Among them,flexible solid-state zinc-air batteries have received widespread attention because of their high energy density,good safety,and stability.Efficient bifunctional oxygen electrocatalysts are the primary consideration in the development of flexible solid-state zinc-air batteries,and self-supported air cathodes are strong candidates because of their advantages including simplified fabrication process,reduced interfacial resistance,accelerated electron transfer,and good flexibility.This review outlines the research progress in the design and construction of nanoarray bifunctional oxygen electrocatalysts.Starting from the configuration and basic principles of zinc-air batteries and the strategies for the design of bifunctional oxygen electrocatalysts,a detailed discussion of self-supported air cathodes on carbon and metal substrates and their uses in flexible zinc-air batteries will follow.Finally,the challenges and opportunities in the development of flexible zinc-air batteries will be discussed.

支架辅助栓塞治疗颅内破裂宽颈动脉瘤的安全性和有效性:Solitaire支架和Neuroform支架的比较

目的比较Solitaire支架和Neuroform支架辅助弹簧圈栓塞治疗颅内破裂宽颈动脉瘤的安全性和有效性。方法回顾性分析2017年9月至2022年10月支架辅助栓塞治疗的118例颅内破裂宽颈动脉瘤的临床资料,其中采用Solitaire支架45例,Neuroform支架73例。结果术中所有支架均成功展开,无支架打开不良或移位,无弹簧圈突入载瘤动脉瘤。术后即刻造影显示,Solitaire支架组动脉瘤完全闭塞率(84.4%,38/48)与Neuroform支架组(86.3%,65/73)无统计学差异(P=0.683)。Solitaire支架组1例术中出现动脉瘤破裂出血,Neuroform支架组1例术后出现局部脑缺血;两例病人出院时均无明显神经功能受损。出院时,Solitaire支架组预后良好率(86.7%,39/45)与Neuroform支架组(87.7%,64/73)无统计学差异(P=0.874)。107例(90.7%,107/118)获得临床随访(102~458 d;平均145 d),Solitaire支架组末次随访预后良好率(86.0%,37/43)与Neuroform支架组(85.9%,55/64)无统计学差异(P=0.323)。88例(74.8%,88/118)接受影像学随访(213~817 d;平均264 d),Solitaire支架组末次随访动脉瘤完全闭塞率(92.1%,35/38)与Neuroform支架组(90.0%,45/50)无统计学差异(P=0.670)。随访期间未发生出血或缺血事件。结论对于颅内破裂宽颈动脉瘤,采用Solitaire支架和Neuroform支架辅助栓塞治疗是安全的、有效的,二者的安全性和有效性相当。

The Design of an Air Rower That Can Purify Indoor Air

To solve the problem that utilizing an air rower lowers indoor air quality due to the dust stirred up in the course of rowing, an air rower is designed to have the extra function of air purifying. The designed rower is composed of six parts, which are the frame, air generator, transmission part, air purifying filter cartridge, performance monitor, and electric motor. To fulfill the task, the filter cartridge is vertically arranged to lead the air to enter from the lower part and vent out of the upper part to filter and purify the air before it enters the generator so as that the indoor air is well circulated to improve the air purification effect when the rower is utilizing. The modular detachable design allows the air filter and electric motor to be installed and disassembled to adapt to different air purification needs. The designed rower has the benefit of lower purchasing cost and energy saving that may motivate exercising, bringing more fun and the sense of accomplishment.

Impact of the Inlet Flow Angle and Outlet Placement on the Indoor Air Quality

This study aims to optimize the influence of the inlet inclination angle on the Indoor Air Quality(IAQ),heat,and temperature distribution in mixed convection within a two-dimensional square cavityfilled with an air-CO_(2)mixture.The air-CO_(2)mixture enters the cavity through two inlet openings positioned at the top wall,which is set at the ambient temperature(TC).Three values of the Reynolds numbers,ranging from 1000 to 2000,are considered,while the Prandtl number is kept constant(Pr=0.71).The temperature distribution and streamlines are shown for Rayleigh number(Ra)equal to 104,three inlet inclination anglesϕ(0,π/6 andπ/4)and three CO_(2)concentrations values(1500,2500,3500 ppm)applied at both hot vertical walls(maintained at a constant temperature TH).Afinite volume method is used under the assumption of two-dimensional laminarflow to solve the NavierStokes and energy equations.The results indicate that inlet inclination angle has an impact on the indoor air quality(IAQ),which,in turn,affects the heat transfer distribution and thermal comfort within the cavity.

Space/Air Covert Communications:Potentials,Scenarios,and Key Technologies

Space/air communications have been envisioned as an essential part of the next-generation mobile communication networks for providing highquality global connectivity. However, the inherent broadcasting nature of wireless propagation environment and the broad coverage pose severe threats to the protection of private data. Emerging covert communications provides a promising solution to achieve robust communication security. Aiming at facilitating the practical implementation of covert communications in space/air networks, we present a tutorial overview of its potentials, scenarios, and key technologies. Specifically, first, the commonly used covertness constraint model, covert performance metrics, and potential application scenarios are briefly introduced. Then, several efficient methods that introduce uncertainty into the covert system are thoroughly summarized, followed by several critical enabling technologies, including joint resource allocation and deployment/trajectory design, multi-antenna and beamforming techniques, reconfigurable intelligent surface(RIS), and artificial intelligence algorithms. Finally, we highlight some open issues for future investigation.