Vascular air embolism

Millimeter-scale soft capsules for sampling liquids in fluid-filled confined spaces

Sampling liquids in small and confined spaces to retrieve chemicals and microbiomes could enable minimally invasive monitoring human physiological conditions for understanding disease development and allowing early screening. However, existing tools are either invasive or too large for sampling liquids in tortuous and narrow spaces. Here we report a fundamental liquid sampling mechanism that enables millimeter-scale soft capsules for sampling liquids in confined spaces. The miniature capsule is enabled by flexible magnetic valves and superabsorbent polymer, fully wirelessly controlled for on-demand fluid sampling. A group of miniature capsules could navigate in fluid-filled and confined spaces safely using a rolling locomotion. The integration of on-demand triggering, sampling, and sealing mechanism and the agile group locomotion allows us to demonstrate precise control of the soft capsules, navigating and sampling body fluids in a phantom and animal organ ex vivo, guided by ultrasound and x-ray medical imaging. The proposed mechanism and wirelessly controlled devices spur the next-generation technologies for minimally invasive disease diagnosis.

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.

Stroke Secondary to Air Embolism Following Laparoscopic Nissen Fundoplication

An air embolism is characterized by the entry of gas bubbles into the circulatory system, which can lead to the possible occlusion of blood vessels, posing a potentially life-threatening risk. While commonly associated with lung trauma or decompression sickness, it can also result from medical procedures such as central venous catheter insertion or, in our case, gas insufflation for laparoscopic surgery. We present the case of a 65-year-old female who suffered from a stroke secondary to an air embolism after undergoing a laparoscopic Nissen fundoplication in which carbon dioxide insufflation of the abdominal cavity was utilized. We also will discuss the elusive etiology of this complication as well as diagnosis, treatment, and proposed preventative measures.  A 65-year-old female with gastroesophageal reflux disease and a hiatal hernia elected to undergo a laparoscopic Nissen fundoplication for hernia repair. After a successful surgery, the patient was found with significant neurological deficits, including left-sided hemiplegia, numbness in the left hand, hemianopsia, dysarthria, and a National Institutes of Health Stroke Scale score of 20. CT head imaging revealed several low-density foci in the right frontal lobe, while CT neck and chest imaging revealed subcutaneous emphysema and pneumomediastinum. Subsequent labs were significant for an elevated lactate at 7.6 mmol/L. MRI of the brain depicted evidence of an acute infarct in the right frontal lobe with diffusion-weighted imaging (DWI) sequences. The imaging results were correlated with the patient's clinical presentation to establish the diagnosis of a nondominant hemisphere stroke, localized to an anterior branch of the right middle cerebral artery (MCA). After intubation and supportive treatment for three days, the patient was extubated and able to follow commands but had left facial weakness and diminished strength in the left upper and lower extremities. At the two-month follow-up visit, the patient no longer had any focal neurological deficits. Air emboli, though very rare, can occur as a complication in laparoscopic surgeries that utilize CO2 for body cavity insufflation. Patients may be asymptomatic with small, self-limiting emboli, while others may exhibit pulmonary symptoms, cardiac arrest, or focal neurologic changes, depending on the emoji's size and location. Given the wide range of patient presentations, the elevated mortality of laparoscopic procedures complicated by air emboli, and the rare occurrence of focal neurological symptoms as depicted in this case, rapid diagnosis and close postoperative observation and treatment are vital for both short-term and long-term patient outcomes.

Coronary Air Embolism Secondary to Percutaneous Lung Biopsy: A Systematic Review

To determine mortality and morbidity associated with coronary air embolism (CAE) secondary to complications of percutaneous lung biopsy (PLB) and illicit-specific risk factor associated with this complication and overall mortality, we searched PubMed to identify reported cases of CAE secondary to PLB. After assessing inclusion eligibility, a total of 31 cases from 26 publications were included in our study. Data were analyzed using Fisher's exact test. In 31 reported cases, cardiac arrest was more common after left lower lobe (LLL) biopsies (n=4, 80%, p=0.001). Of these patients who suffered from cardiac arrest, CAE was found more frequently in the right coronary artery (RCA) than other locations but did not reach statistical significance (n=5, 62%, p=0.39). At the same time, intervention in the LLL was significantly associated with patient mortality (n=3, 60%, p=0.010). Of the patients who died, CAE was more likely to have occurred in the RCA, but this association was not statistically significant (n=4, 57%, p=0.33). LLL biopsies have a statistically significant correlation with cardiac arrest and patient death. More research is needed to examine the effect of the air location in the RCA on patient morbidity and mortality.

Changes in lung mechanics and ventilation-perfusion match: comparison of pulmonary air- and thromboembolism in rats

BACKGROUND

Pulmonary air embolism (AE) and thromboembolism lead to severe ventilation-perfusion defects. The spatial distribution of pulmonary perfusion dysfunctions differs substantially in the two pulmonary embolism pathologies, and the effects on respiratory mechanics, gas exchange, and ventilation-perfusion match have not been compared within a study. Therefore, we compared changes in indices reflecting airway and respiratory tissue mechanics, gas exchange, and capnography when pulmonary embolism was induced by venous injection of air as a model of gas embolism or by clamping the main pulmonary artery to mimic severe thromboembolism.

METHODS

Anesthetized and mechanically ventilated rats (n = 9) were measured under baseline conditions after inducing pulmonary AE by injecting 0.1 mL air into the femoral vein and after occluding the left pulmonary artery (LPAO). Changes in mechanical parameters were assessed by forced oscillations to measure airway resistance, lung tissue damping, and elastance. The arterial partial pressures of oxygen (PaO2) and carbon dioxide (PaCO2) were determined by blood gas analyses. Gas exchange indices were also assessed by measuring end-tidal CO2 concentration (ETCO2), shape factors, and dead space parameters by volumetric capnography.

RESULTS

In the presence of a uniform decrease in ETCO2 in the two embolism models, marked elevations in the bronchial tone and compromised lung tissue mechanics were noted after LPAO, whereas AE did not affect lung mechanics. Conversely, only AE deteriorated PaO2, and PaCO2, while LPAO did not affect these outcomes. Neither AE nor LPAO caused changes in the anatomical or physiological dead space, while both embolism models resulted in elevated alveolar dead space indices incorporating intrapulmonary shunting.

CONCLUSIONS

Our findings indicate that severe focal hypocapnia following LPAO triggers bronchoconstriction redirecting airflow to well-perfused lung areas, thereby maintaining normal oxygenation, and the CO2 elimination ability of the lungs. However, hypocapnia in diffuse pulmonary perfusion after AE may not reach the threshold level to induce lung mechanical changes; thus, the compensatory mechanisms to match ventilation to perfusion are activated less effectively.

Evaluation of the Catheter Clamp over Hydrophilic Guide Wire Central Venous Catheter Exchange Technique for Air Embolism Prophylaxis in an In Vitro Model

PURPOSE

To develop a reproducible in vitro model simulating central venous catheter (CVC) exchange with high potential for air embolization and test the hypothesis that a closed catheter clamp over hydrophilic guide wire exchange technique will significantly reduce the volume of air introduced during CVC exchange.

MATERIALS AND METHODS

The model consisted of a 16-F valved sheath, 240-mL container, and pressure transducer submerged in water in a 1,200-mL suction canister system. Continuous wall suction was applied to the canister to maintain negative pressure at -7 mm Hg or -11 mm Hg. Each trial consisted of 0.035-inch hydrophilic guide wire introduction, over-the-wire catheter exchange, and wire removal following clinical protocol. A total of 256 trials were performed, 128 trials at each pressure with the catheter clamp open (n = 64) or closed (n = 64) around the hydrophilic guide wire.

RESULTS

There was a statistically significant lower volume of air introduced with closed clamp over-the-wire exchanges than with open clamp exchanges at both pressures (2-tailed t-test, P < .001). At -7 mm Hg, a mean of 48.0 mL (SD ± 9.3) of air was introduced with open clamp and 20.6 mL (SD ± 4.7) of air was introduced with closed clamp. At -11 mm Hg, 97.8 mL (SD ± 11.9) of air was introduced with open clamp and 37.8 mL (SD ± 6.3) of air was introduced with closed clamp.

CONCLUSIONS

This study demonstrated the use of a reproducible in vitro model mimicking conditions causing air embolism during CVC exchange. Results showed that CVC exchange using closed catheter clamp over hydrophilic guide wire exchange technique significantly reduced the volume of air introduced per exchange.

Central venous catheters: Which, when and how

Short-term or long-term CVCs are now considered the standard of practice for the administration of chemotherapy, fluid therapy, antibiotic therapy, and parenteral nutrition. Central venous access catheters are broadly divided into tunneled or non-tunneled catheters. Tunneled catheters can be further subdivided into totally implanted and totally not implanted devices. Device selection generally depends on various factors such as availability of peripheral veins, expected duration of therapy, and desired flow rate. Ultrasound-guided access is the safest technique for central venous access compared to the landmark technique and departments should strive to for a 100% ultrasound guided access. This review gives a basic overview of the differences of CVC catheters including PICCs, Hickman-catheters and port-catheters along with the criteria for CVC selection. It will also describe technical tips on placement of CVCs. Finally, it aims to highlight complications which are associated with CVC placement and options to treat or prevent them.

Investigating the Mechanism of Intravascular Bubble Formation in Designed Arrays of Vascularized Systems on a Chip

Vascular gas embolism is a rare medical condition, resulting from the existence of air or gas in the venous or arterial system. Gas embolism is associated with a wide range of circulatory, cardiovascular, and neurological complications that can lead to sudden and unexplained death. Despite the recent increase in related studies, gas embolism remains under-reported with a poor understanding of its genesis and pathophysiology. In this work, intravascular bubble formation is investigated in an array of biomimetic microscale systems, where the endogenous generation of gas bubbles is induced by variations in the surrounding pressure. Microfluidic devices, based on polydimethylsiloxane, are designed and fabricated as vascularized systems on a chip with one main channel at two different diameters (30 µm, and 40 µm), surrounded by a pressure chamber (200 µm) on each side, at a separation of 50 µm. Two blood-equivalent solutions, at 20% and 46% hematocrit concentrations were prepared from a glycerin and xanthan gum mixture to mimic the physicochemical characteristics of the blood. As the volume of injected air increased, the events related to gas embolism were occurring at shorter timespans with more significant characteristics, i.e., length and number of bubbles. Additionally, correlations were established between the input parameters, i.e., the vascular diameter and equivalent hematocrit concentration, and the output parameters, i.e., the bubble size, velocity, frequency, and nucleation sites.Clinical Relevance- The reported results constitute a reproducible observation and quantification of intravascular bubble formation induced by global pressure variations, where the emergence of bubbles exhibits different patterns depending on biological characteristics related to gender and medical history.

Incidental Finding of Venous Air Embolism: A Case Report

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.

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.

Detection of paradoxical carbon dioxide gas embolism with opening of patent foramen ovale by perioperative transesophageal echocardiography during laparoscopic hepatectomy - A case report -

Background: Due to its various advantages, laparoscopic surgery is preferred over laparotomy in patients who require hepatic resection. Carbon dioxide embolism —which occurs approximately ten times more often in laparoscopic hepatectomy than in general laparoscopic surgery—presents with insignificant symptoms and may be overlooked.Case: A 70-year-old male with hepatic cell carcinoma underwent laparoscopic hepatectomy. Though his vital signs were stable during the initiation of surgery, they became unstable during the procedure. The surgeon detected portal vein rupture, and transesophageal echocardiography was subsequently performed. A large amount of gas in the heart chamber and paradoxical embolism through a patent foramen ovale due to a right-to-left shunt were observed. We treated the symptoms, and the surgery was completed without any further issues.Conclusions: Active use of transesophageal echocardiography to identify and monitor heart functions during a suspected carbon dioxide embolism can significantly reduce morbidity and mortality associated with that embolism.

Isolated Right Ventricular Air Embolism

Vascular air embolism (VAE) is an uncommon but potentially life-threatening event often associated with various procedures and diagnostic tests. Understanding this challenging incident will enable physicians to evaluate, diagnose and manage this incident successfully. We present a case of a 73-year-old male who developed air in the right ventricle after intravenous contrast-enhanced computed tomography (CT) imaging. We aim at highlighting this challenging clinical scenario and emphasizing ways to assess the risks and implement means to prevent and treat accordingly.

Stroke-Like Symptoms During Sexual Intercourse in a 25-Year-Old Female with a Patent Foramen Ovale

A 25-year-old female who presented with stroke-like symptoms during sexual intercourse was found to have a patent foramen ovale (PFO). She was diagnosed with a cryptogenic transient ischemic attack (TIA) and underwent a successful catheter-based PFO closure. She had complete resolution of symptoms during both intercourse and physical activity.

Carbon dioxide embolism during transanal total mesorectal excision: A hint of prevention from a case report

Transanal total mesorectal excision is a relatively new approach for treating lower rectal cancer. Carbon dioxide embolism is a critical complication of this procedure. We report the case of a 69-year-old man with lower rectal cancer who underwent transanal total mesorectal excision followed by laparoscopic low anterior resection. He had a sudden intraoperative carbon dioxide embolism during the transanal mesorectal excision. During the ventral dissection of the rectum, end-tidal carbon dioxide and blood oxygen saturation suddenly decreased. We stopped the insufflation of carbon dioxide and suspended the procedure. There was no circulatory collapse, and the vital signs gradually recovered; therefore, we resumed the surgery approximately 30 minutes later and completed it without additional complications. Upon reviewing the video, we found a small injured vein that would aspirate carbon dioxide. These findings suggested that careful hemostasis is essential to prevent carbon dioxide embolus during transanal total mesorectal excision.

Bedside Ultrasound Detection of Systemic Air Embolism Secondary to Fulminant Necrotizing Enterocolitis in a Neonate With Congenital Heart Disease: A Case Report

Systemic air embolism is a rarely reported complication of necrotizing enterocolitis in the neonatal population. It carries significant morbidity and mortality. We report a 6-day-old, term female neonate with a duct-dependent (systemic) congenital heart disease (interrupted aorta with patent ductus arteriosus and ventricular septal defect) who presented in extremis. The neonate was successfully resuscitated, mechanically ventilated, and put on intravenous prostaglandins in paediatric intensive care unit. She clinically improved but later she developed necrotizing enterocolitis which was complicated by systemic air embolism; both of which were identified by bedside ultrasound. Her condition deteriorated and she succumbed due to these complications.

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.

Cerebral Air Embolism After Gastrointestinal Procedure: A Case Report and Literature Review

Esophagogastroduodenoscopy (EGD) is one of the forefronts of minimally invasive modalities with excellent safety records and tremendous capability but despite its accolades and functions, there are still very rare complications including air embolism. It is a life-threatening condition that could lead to a significant increase in morbidity and mortality. However, there are limited data for incidence of air embolism in association with gastrointestinal endoscopy. Diagnosis of air embolism after or during gastrointestinal endoscopy might be a difficult task due to overlapping presentations with anesthesia effects on the cardiopulmonary and the neurological systems, as a result, there should be increased awareness allowing clinicians to quickly rule out air embolism in patient with altered mental status or cardiopulmonary changes after or during gastrointestinal endoscopy. Herein, we report a unique case of cerebral air embolism after EGD in a 79-year-old female patient. In addition, we also performed a systematic review of cases based on PRISMA guideline, with the aim to investigate the demographics and clinical outcomes associated with this complication. This systematic review of cases hopes to increase the awareness about this rare entity.

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.

Standardization and Chemical Characterization of Intravenous Therapy in Adult Patients: A Step Further in Medication Safety

BACKGROUND

Intravenous drug administration is associated with potential complications, such as phlebitis. The physiochemical characteristics of the infusate play a very important role in some of these problems.

AIM

The aim of this study was to standardize the dilutions of intravenous drugs most commonly used in hospitalized adult patients and to characterize their pH, osmolarity and cytotoxic nature to better guide the selection of the most appropriate vascular access.

METHODS

The project was conducted in three phases: (i) standardization of intravenous therapy, which was conducted using a modified double-round Delphi method; (ii) characterization of the dilutions agreed on in the previous phase by means of determining the osmolarity and pH of each of the agreed concentrations, and recording the vesicant nature based on the information in literature; and (iii) algorithm proposal for selecting the most appropriate vascular access, taking into account the information gathered in the previous phases.

RESULTS

In total, 112 drugs were standardized and 307 different admixtures were assessed for pH, osmolarity and vesicant nature. Of these, 123 admixtures (40%), had osmolarity values >600 mOsm/L, pH < 4 or > 9, or were classified as vesicants. In these cases, selection of the most suitable route of infusion and vascular access device is crucial to minimize the risk of phlebitis-type complications.

CONCLUSIONS

Increasing safety of intravenous therapy should be a priority in the healthcare settings. Knowing the characteristics of drugs to assess the risk involved in their administration related to their physicochemical nature may be useful to guide decision making regarding the most appropriate vascular access and devices.

Venous Air Embolism Identified by 18F-Fluorocholine Dual-Phase PET/CT

ABSTRACT

A 60-year-old woman with primary hyperparathyroidism with previous nonconclusive imaging studies was referred for 18F-fluorocholine (18F-FCH) PET/CT as part of the preoperative diagnostic imaging workup to localize the adenoma before minimally invasive surgery. 18F-FCH PET/CT with dual time point was performed, acquiring immediately and 60 minutes after 18F-FCH administration. The early images demonstrated possible hyperfunctioning parathyroid tissue in the mediastinum, located in the right upper paratracheal space (region 2R), with an incidental iatrogenic subclavian venous air bubble embolism presenting as high uptake in the early images that disappeared in the late images. No symptomatology was reported during the examination.

Rare pathology in a trauma patient: air embolism following peripheral intravenous access

A 62-year-old man presented as a trauma alert after a farm tractor accident. He was managed according to ATLS protocol. During initial trauma resuscitation, he developed an iatrogenic air embolus. The patient was treated conservatively by positioning him head down and tilted to the left (Durant's manoeuvre). Repeat CT scan performed 4 hours later showed resolution of the air embolus. He had no sequelae.

Anesthetic Management of Patients Undergoing Open Suboccipital Surgery

The posterior cranial fossa with its complex anatomy houses key pathways regulating consciousness, autonomic functions, motor and sensory pathways, and cerebellar centers regulating balance and gait. The most common posterior fossa pathologies for which neurosurgical intervention may be necessary include cerebellopontine angle tumors, aneurysms, and metastatic lesions. The posterior cranial fossa can be accessed from variations of the supine, lateral, park-bench, prone, and sitting positions. Notable complications from positioning include venous air embolism, paradoxic air embolism, tension pneumocephalus, nerve injuries, quadriplegia, and macroglossia. An interdisciplinary approach with careful planning, discussion, and clinical management contributes to improved outcomes and reduced complications.

Intracranial Air Embolism after Inferior Alveolar Nerve Block: A Case Report

INTRODUCTION

The number of nontraumatic dental pain emergency department (ED) visits continues to substantially rise in frequency every year. While there are several methods for treating dental pain, an inferior alveolar nerve block (IANB) is a non-narcotic alternative that provides instantaneous relief of severe pain.

CASE REPORT

A 59-year-old male presented to the ED from a dentist's office for evaluation of a right-sided headache with an associated episode of palpitations and near syncope that developed while receiving an inferior alveolar nerve block. Computed tomography of the patient's head revealed multiple small foci of air in the right temporalis muscle and in the intracranial venous drainage system. Given the patient's history of dental procedure, the intravascular introduction of air and local anesthetic was suspected.

CONCLUSION

Inferior alveolar nerve block procedures can have complications, including hematoma formation, trismus, facial palsy, needle breakage, and in this case, intravascular injection and cerebral air embolism. To perform a successful IANB, it is critical for providers to be familiar with anatomical landmarks and to consistently perform aspiration to confirm that needle placement is not intravascular.

Hospital-Acquired Conditions after Liver Transplantation

Hospital-acquired conditions (HACs) are used to define hospital performance measures. Patient comorbidity may influence HAC development. The National Inpatient Sample database was used to investigate HACs for the patients who underwent liver transplantation. Multivariate analysis was used to identify HAC risk factors. We found a total of 13,816 patients who underwent liver transplantation during 2002–2014. Of these, 330 (2.4%) had a report of HACs. Most frequent HACs were vascular catheter–associated infection [220 (1.6%)], falls and trauma [66 (0.5%), catheter-associated UTI [24 (0.2%)], and pressure ulcer stage III/IV [22 (0.2%)]. Factors correlating with HACs included extreme loss function (AOR: 52.13, P < 0.01) and major loss function (AOR: 8.11, P = 0.04), hepatopulmonary syndrome (AOR: 3.39, P = 0.02), portal hypertension (AOR: 1.49, P = 0.02), and hospitalization length of stay before transplant (AOR: 1.01, P < 0.01). The rate of HACs for liver transplantation is three times higher than the reported overall rate of HACs for GI procedures. Multiple patient factors are associated with HACs, and HACs may not be a reliable measure to evaluate hospital performance. Vascular catheter–associated infection is the most common HAC after liver transplantation.

Intraoperative venous air embolism in the non-cardiac surgery-the role of perioperative echocardiography in a case series report

Venous air embolism (VAE) is commonly one of the iatrogenic complications associated with divergent high-risk surgeries. In this case-series report, we presented a series of VAE cases in our institute during the last 6 consecutive years. There were total of nine cases suspected to be VAE according the clinical symptom and signs, of which seven cases were definitively diagnosed VAE using transthoracic echocardiography (TTE). We also reported two presumptive cases of paradoxical VAE during hepatectomy in this case series, furthermore, the cause, complications and hazards secondary to paradoxical VAE were discussed as well. All cases had an uneventful recovery from VAE with the assistance of TTE as well as other therapeutic management of VAE, except one neurosurgical patient died from postoperative hemorrhagic stroke per se. Therefore, VAE or paradoxical air embolism can occur during various non-cardiac operations and the significance of perioperative ultrasound should be emphasized in the treatment of VAE.

Acceptability of external jugular venepuncture for patients with liver disease and difficult venous access

BACKGROUND

Difficult venous access (DVA) is common in liver patients requiring blood collection using traditional peripheral approaches. This study aimed to understand the experience of DVA for liver patients and the acceptability of peripheral venepuncture versus external jugular venepuncture (EJV). A secondary aim was to explore the impact of EJV on local resource utilization.

METHODS

Semistructured interviews with liver outpatients with DVA (n = 10) requiring venepuncture were firstly themed inductively. We then deductively applied the acceptability framework of Sekhon et al. as a further analytic lens. Audit data from DVA encounters (n = 24) allowed analysis of issues from multiple perspectives. The Consolidated Criteria for Reporting Qualitative Research reporting checklist guides this report.

RESULTS

Peripheral venepuncture had poor prospective, concurrent, and retrospective acceptability, requiring significant mental and physical preparation. Fear, stigma, pain and distress, poor continuity of care, and poor effectiveness led to service disengagement. While EJV caused initial trepidation, it had high concurrent and retrospective acceptability. The significant improvement in patient experience was corroborated by audit data for both procedure duration (5 versus 15 minutes) and first attempt success (100 versus 28.5%) for EJV versus peripheral venepuncture, respectively. While EJV required a recumbent position, it required less staff.

CONCLUSIONS

EJV is highly acceptable to patients, using less time and staff resources. EJV protocols and staff training should be considered where DVA presentations are common. Individualized care plans and careful care coordination could divert DVA patients needing venepuncture to services that use EJV preferentially. HIGHLIGHTS Peripheral venepuncture results in fear, stigma, pain, & distress for those with DVA. This poor acceptability of traditional venepuncture leads to service disengagement. External jugular venepuncture is highly acceptable & improves resource utilization.

A life-threatening condition: The pulmonary artery air embolism

Introduction

Air embolism is a very rare condition which occurs when air or gas enter into the vascular system in either the venous or arterial route. It can occur following a variety of circumstances ranging from invasive procedures to either blunt or penetrating trauma conditions.

Case presentation

We present a case of a 39-year-old male who had an air embolism in the pulmonary artery as a consequence of the injection of a contrast agent. He had dyspnea and chest pain following a contrast-enhanced chest computed tomography imaging. He was successfully treated and discharged from our hospital.

Conclusion

Air embolism is rare, but can be fatal. The critical care providers should be familiar with the signs indicating air embolism and be ready to perform the main therapeutic maneuvers. Early detection of this clinical condition is essential to prevent morbidity and mortality.

Complications of central venous port systems: a pictorial review

Central venous port devices are indicated for patients, who need long-term intravenous therapy. Oncologic patients may require intermittent administration of chemotherapy, parenteral nutrition, infusions, or blood transfusions. A venous port system is composed of a port chamber attached to a central catheter, which is implanted into the central venous system. The subcutaneous location of the catheter chamber improves the patients’ quality of life and the infection rate is lower than in non-totally implantable central venous devices. However, proper implantation, use, and care of a port system are important to prevent short- and long-term complications. Most common early complications (< 30 days) include venous malpositioning of catheter and perforation with arterial injury, pneumothorax, hemothorax, thoracic duct injury, or even cardiac tamponade. Delayed complications include infection, catheter thrombosis, vessel thrombosis and stenosis, catheter fracture with extravasation, or fracture with migration or embolization of catheter material. Radiologic imaging has become highly relevant in intra-procedural assessment and postoperative follow-up, for detection of possible complications and to plan intervention, e.g., in case of catheter migration. This pictorial review presents the normal imaging appearance of central venous port systems and demonstrates imaging features of short- and long-term complications.

Air embolism following peripheral intravenous access

Air embolism is a rare, often misdiagnosed, potentially fatal condition. It is most frequently associated with invasive vascular procedures and mechanical ventilation. Air emboli developing from peripheral intravenous lines are uncommon. We present a case of symptomatic venous air embolism likely arising from peripheral intravenous access gained during an interventional pain procedure. This case highlights the need to consider air embolism in the differential diagnoses of patients presenting with neurological symptoms following vascular interventions.

Massive Carbon Dioxide Embolism During Laparoscopic Liver Resection: A Case Report

Carbon dioxide embolism during laparoscopic surgery is a serious and life-threatening complication. The overall incidence of embolism during laparoscopic surgery is low (0.15%). Although the potential fatal consequences of this complication are reported in literature, a well-documented report of the effect of massive CO2 embolism during laparoscopic liver resection on cardiovascular, respiratory and encephalographic parameters does not exist. The authors describe a well-documented case of massive carbon dioxide embolism during laparoscopic liver resection suspected by both hemodynamic instability and elevation of EtCO2 and confirmed by arterial blood gas. The surgeon's rapid closure of the vascular breach resulted in an overall improvement of the patient's vital signs without further consequences. Our case report shows the cardiovascular, respiratory and encephalographic effects of a massive carbon dioxide embolism and highlights the importance of a strict cooperation between the surgeon and the anesthesiologist and the importance for a prompt treatment when massive carbon dioxide embolism occurs.

Air embolism through open hub of external jugular vein intravenous cannula

Introduction

Venous air embolism is a catastrophic complication that can result in sudden cardiac arrest and death. Massive air embolism has been reported with central venous catheter through the internal jugular and subclavian veins. Though external jugular vein is a potential site of an air embolism to cardiac chambers and subsequently to vital organs such as brain, heart and lungs but has not been reported yet in literature.

Case presentation

We are reporting a case of sudden pulmonary air embolism in a patient through the open hub of an intravenous cannula, vigilant monitoring and timely action saved the patient from a catastrophic outcome.

Conclusion

We recommend vigilant monitoring and adequate precaution in patients with external jugular venous cannulation in the operation theater, intensive care unit or wards to prevent iatrogenic complications.

Complications of endoscopic retrograde cholangiopancreatography: an imaging review

Endoscopic retrograde cholangiopancreatography (ERCP) has currently become an inseparable tool in the gastroenterologist's armamentarium for treatment of pancreaticobiliary disorders. Given the increase in number of therapeutic ERCP procedures today, the need for prompt and correct diagnosis of its complications is pivotal. This review discusses the mechanisms, risk factors, imaging findings and general management aspects of common and rare complications of ERCP. Furthermore, the review elaborates on imaging indications, recommended protocol and normal imaging findings post ERCP.

Pneumodissection during Percutaneous Renal Ablation Resulting in Air Embolism: Percutaneous Management and a Review of the Literature

Percutaneous renal ablation is a nephron-sparing approach for selected patients with renal cell carcinoma. Common complications include hemorrhage, injury to the urinary collecting system, and abscess formation. The purpose of this article is to present a case of vascular air embolism as a complication of pneumodissection performed during percutaneous ablation of renal cell carcinoma, discuss its successful percutaneous management, review common complications of renal ablation, and outline steps physicians can take to lessen these complications.

Venous carbon dioxide embolism during laparoscopic cholecystectomy a literature review

Laparoscopy has become the procedure of choice for routine gallbladder removal. A serious complication of this technique is the occurrence of gas emboli due to insufflation. It is associated with a high mortality rate of around 28%. The present systematic review intends to provide more insight into causes, symptoms and risk factors for this specific complication and to explore which measures should be taken to treat and prevent it. The Cochrane library and Pubmed were used as sources. Articles and their references were selected when they were related to the subject in sufficient detail. The course of this complication can vary from asymptomatic up to impairment of normal flow through the right ventricle (RV) or pulmonary artery, potentially leading to acute heart failure. The severity depends on the amount of gas, the rate of accumulation and the ability to remove the gas bubbles. It is difficult to estimate the true incidence of venous gas embolism during laparoscopic cholecystectomy as there are various diagnostic tools, each with different sensitivity. Precautions that need to be taken are: correct positioning of the needle, low insufflation pressure, low insufflation speed, screening for hypovolemia, Trendelenburg positioning, availability of intervention equipment at operation table, no placement of venous catheters during inspiration and catheter removing during expiration. Physicians need to be more aware of this harmful complication and the preventative measurements that need to be taken. As there are virtually no prospective data, future studies are needed to gain more knowledge on gas emboli during laparoscopic cholecystectomy.

Massive gas embolism in a child

A 16-month-old girl who was hospitalized with pneumonia and treated with antibiotics died after the nurse erroneously connected her intravenous left forearm catheter to the oxygen supply. Autopsy revealed an impressive gas embolism in the left subclavian and brachiocephalic veins, reduced crepitus and enlarged lung volume, and congestion of the meningeal vessels with some areas showing small air bubbles. Dilation of the right atrium and the right ventricle with efflux under pressure of large amounts of air bubbles were observed. The coronary arteries and veins were filled with air bubbles intercalated with segments containing blood. After exclusion of putrefactive artifacts as the source of such a large amount of gas in the body death was considered to be due to a massive air embolism. While embolisms are well recognized in adults, these cases are only infrequently encountered in forensic practice in younger decedents.

Air Embolism into Superior Mesenteric Artery Following Replacement of Ascending Aorta for Aortic Dissection - A Rare and Fatal Case

We report an unusual case of fatal air embolism into the superior mesenteric artery in a patient, who underwent replacement of the ascending aorta for aortic dissection type A. CT performed twice on the first postoperative day showed abundant air in the superior mesenteric artery and its branches (but not in the portal-venous system) indicating air embolism with no signs of bowel necrosis. On the second postoperative day, the patient underwent extensive bowel resection due to bowel ischemia and died on the third postoperative day on MODS/SIRS.

Uncommon Occurrences of Air Embolism: Description of Cases and Review of the Literature

Many different risk factors have been associated with the occurrence of gas embolism making this potentially lethal complication easily avoidable. However, this condition can occur in circumstances not commonly reported. Three different and extremely uncommon cases of gas embolism are presented and discussed: the first was caused by the voluntary ingestion of hydrogen peroxide, the second occurred during a retrograde cholangiopancreatography, and the last followed the intrapleural injection of Urokinase. Whereas in the first patient the gas embolism was associated with only relatively mild digestive symptoms, in the remaining two it caused a massive cerebral ischemia and an extended myocardial infarction, respectively. Despite a hyperbaric oxygen therapy performed timely in each case, only the first patient survived. The classical risk factors associated with gas embolism like indwelling central venous catheters, diving accidents, etc. are rather well known and thus somewhat preventable; however, a number of less common and difficult-to-recognize causes can determine this condition, making the correct diagnosis elusive and delaying the hyperbaric oxygen therapy, whose window of opportunity is rather narrow. Thus, a gas embolism should be suspected in the presence of not otherwise explainable sudden neurologic and/or cardiovascular symptoms also in circumstances not typically considered at risk.

Catheter-associated venous air embolism in hospitalized horses: 32 cases

Background

Venous air embolism is a potentially life‐threatening complication of IV catheter use in horses. Despite widespread anecdotal reports of their occurrence, few cases have been reported in the literature and the prognosis is currently unknown.

Hypothesis/Objectives

Our objective was to describe the surrounding circumstances, clinical signs, treatment, progression, and outcome of venous air embolism in hospitalized horses.

Animals

Thirty‐two horses with acute onset of compatible clinical signs associated with IV catheter disconnection or damage.

Methods

Multicenter retrospective study. Data extracted from clinical records included signalment, presenting complaint, catheter details, clinical signs, treatments, and outcome.

Results

Most cases resulted from extension set disconnection occurring within approximately 24 hours after catheter placement. In fewer horses, extension set damage was cited as a cause. Common clinical signs included tachycardia, tachypnea, recumbency, muscle fasciculations and agitation, with abnormal behavior including kicking and flank biting. Less commonly, pathological arrhythmias or more severe neurologic signs, including blindness and seizures, were noted. Progression was unpredictable, with some affected horses developing delayed‐onset neurologic signs. Mortality was 6/32 (19%), including 2 cases of sudden death and other horses euthanized because of persistent neurologic deficits. Negative outcomes were more common in horses with recorded blindness, sweating or recumbency, but blindness resolved in 5/8 affected horses.

Conclusions and Clinical Importance

The prognosis for resolution of clinical signs after air embolism is fair, but permanent neurologic deficits or pathologic cardiac arrhythmias can arise. Unpredictable progression warrants close monitoring. Systematic clinic‐based surveillance could provide additional useful information to aid prevention.