Fatal systemic venous air embolism during endoscopic retrograde cholangiopancreatography

Complications of Endoscopic Retrograde Cholangiopancreatography

Up to 1 in 6 patients will experience an unplanned hospitalization after endoscopic retrograde cholangiopancreatography (ERCP), largely for the evaluation and management of adverse events. Therefore, a commitment to the prevention, early recognition, and effective rescue of complications related to ERCP is critical toward improving outcomes. ERCP is most often complicated by acute pancreatitis, bleeding, infection, or perforation, although myriad other adverse events may occur. The prevention of post-ERCP pancreatitis has been the area of greatest interest and progress in the last decade, but the application of evidence-based prophylactic measures remains inconsistent. Innovations in stent, hemostasis, and perforation closure technology now allow effective and efficient endoscopic management of several important nonpancreatitis complications. Overall, our ability to prevent and treat ERCP-related adverse events has improved substantially, amplifying the importance of a high level of suspicion for and a thorough understanding of these events.

Gas Pressure From the Endoscope: An Unexplored Contributor to Morbidity and Mortality?

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.

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.

When in Trouble Think of the Bubble: Paradoxical Cerebral Arterial Gas Embolism after Endoscopic Retrograde Cholangiopancreatography

Air embolism (a result of direct communication with the vasculature and an external pressure gradient from the gastrointestinal or the biliary tract), although rare, is a potentially devastating adverse event seen in endoscopic retrograde cholangiopancreatography (ERCP) procedures. Whether venous, arterial, or paradoxical, the clinical presentation ranges from asymptomatic patients to cardiorespiratory arrest. This is of particular importance because it makes the diagnosis of air embolism even more difficult in an already sedated patient. Since early recognition increases the chances of patients' survival, endoscopists should be highly motivated and trained to recognize this complication as early as possible. With only 60 cases of air embolism reported (and even fewer related to paradoxical air embolism), we aimed to report a case of paradoxical cerebral air embolism in a patient undergoing ERCP due to a common bile duct stricture and to provide a mini-review of this clinical entity that can serve as a bedside quick reference guide for endoscopists worldwide.

CO2 or air cholangiography reduces the risk of post-ERCP cholangitis in patients with Bismuth type IV hilar biliary obstruction

Background

Endoscopic biliary stenting by endoscopic retrograde cholangiopancreatography (ERCP) is the most common form of palliation for malignant hilar obstruction. However, ERCP in such cases is associated with a risk of cholangitis. The incidence of post-ERCP cholangitis is particularly high in Bismuth type IV hilar obstruction, and this risk is further increased when the contrast injected for cholangiography is not drained. The present study aims to compare the incidence of cholangitis associated with the use of a contrast agent, air and CO₂ for cholangiography in type IV hilar biliary lesions.

Methods

The clinical data of consecutive 70 patients with type IV hilar obstruction, who underwent ERCP from October 2013 to November 2017, were retrospectively analyzed. These patients were divided into three groups based on the agent used for cholangiography: group A, contrast (n = 22); group B, air (n = 18); group C, CO₂ (n = 30). These three methods of cholangiography were chronologically separated. Prior to the ERCP, MRCP was obtained from all patients to guide the endoscopic intervention.

Results

At baseline, there was no significant difference in terms of the patient’s age, gender, symptoms and liver function tests among the three groups (P > 0.05). The complication rates were significantly higher in group A than in groups B and C (63.6% vs. 26.7 and 27.8%, P < 0.05). The incidence of post-ERCP cholangitis was significantly higher in group A (P < 0.05), while the incidence of post-ERCP pancreatitis and bleeding were similar in the three groups. After the ERCP, the mean hospital stay was shorter in groups B and C, when compared to group A (P < 0.05). However, there was no significant difference in the 30-day mortality rate among the three groups (P > 0.05). Furthermore, there was no significant difference between groups B and C in terms of primary end points.

Conclusion

CO₂ or air cholangiography during ERCP for type IV hilar obstruction is associated with reduced risk of post-ERCP cholangitis, when compared to conventional contrast agents.

Clinical Presentation, Diagnosis, and Management of Air Embolism During Endoscopic Retrograde Cholangiopancreatography

Endoscopic retrograde cholangiopancreatography (ERCP) is a minimally invasive procedure that is widely used by endoscopists and has a robust therapeutic profile. It uses endoscopy and imaging for a variety of diagnostic as well as therapeutic purposes. It is used for the management of a lot of pancreaticobiliary diseases such as obstructive jaundice, obstruction related to bile ducts, pancreatic biliary tumors, and traumatic or iatrogenic damage to the bile ducts. Other therapeutic interventions that can be done via ERCP include sphincterotomy, dilation of strictures, removal of biliary stones and placement of stents. Air embolism presents with cardiovascular, pulmonary, and neurologic signs and symptoms. Treatment of air embolism should be started early in suspected cases, and it should be in the differential diagnoses of various complications secondary to high risk of ERCP, especially if a cardiopulmonary compromise is present. Air embolism is rare but a serious complication associated with ERCP. The physicians must keep this in mind while performing ERCP in patients with predisposing risk factors. This review highlights the mechanism, causes, risk factors, pathophysiology, clinical signs, diagnostic modalities, treatment, and preventive measures to deal with this catastrophic complication.

Air embolism secondary to endoscopy in hospitalized patients: results from the National Inpatient Sample (1998-2013)

Background:

Air embolism is a rare, but potentially catastrophic complication of endoscopic procedures. We herein evaluated the overall incidence of air embolism after endoscopy. We also measured mortality outcomes after air embolism.

Methods:

Patients who underwent endoscopy as an index procedure during hospitalization were selected from the National Inpatient Sample from 1998-2013. The primary outcome of interest was the incidence of air embolism after endoscopy. All-cause mortality after endoscopy was measured as a secondary outcome and the Charlson Comorbidity Index was calculated. Binary logistic regression was used to explore the effect of air embolism on inpatient mortality, using P<0.05 as level of significance.

Results:

A total of 2,245,291 patients met the inclusion criteria. Mean age at the time of procedure was 62.5 years. Esophagogastroduodenoscopy (EGD) was the most common endoscopic procedure, accounting for 80% of endoscopic procedures. Air embolism occurred in 13 cases, giving a rate of 0.57 per 100,000 endoscopic procedures. Air embolism was most common after endoscopic retrograde cholangiopancreatography (ERCP), occurring in 3.32 per 100,000 procedures, compared with 0.44 and 0.38 per 100,000 procedures for EGD and colonoscopy, respectively. The case fatality rate for post endoscopic air embolism was 15.4%. After adjusting for covariates, air embolism after endoscopy was independently associated with higher odds of inpatient mortality: odds ratio 10.35, 95% confidence interval 1.21-88.03 (P<0.03).

Conclusions:

Air embolism is most common after ERCP. It is frequently associated with disorders involving a breach to the gastrointestinal mucosa or vasculature. Though rare, it is an independent predictor of inpatient mortality.

Air Embolism during Upper Endoscopy: A Case Report

Air embolism is a rare complication of upper endoscopy and potentially causes life-threatening events. A 67-year-old man with a history of surgery of cardiac carcinoma and pancreatic neuroendocrine tumor underwent painless upper endoscopy because of tarry stools. During the procedure, air embolism developed, which caused decreased pulse oxygen saturation and delayed sedation recovery. He recovered with some weakness of the left upper limb in the intensive care unit without hyperbaric oxygen therapy. The etiology, clinical manifestations, and treatments of air embolism are discussed based on the literature reports. Although air embolism is uncommon in endoscopic examinations, the patients’ outcomes could be improved if clinicians are alert to this potential complication, and promptly start proper diagnostic and therapeutic measures.

Gas embolism during endoscopic retrograde cholangiopancreatography: diagnosis and management

Air embolism is rarely diagnosed and is often fatal. The diagnosis is often not made in a timely manner given the rapid and severe clinical deterioration that often develops, frequently leading to cardiac arrest. Many patients are only diagnosed post-mortem. With the increasing use of endoscopic retrograde cholangiopancreatography, air embolism should be considered in the differential diagnosis in patients who experience sudden clinical deterioration during or immediately after the procedure. Clinical suspicion is key in the diagnosis and management of air embolism. Use of precordial Doppler ultrasound and transesophageal echocardiogram can aid in the diagnosis of air embolism. Once the diagnosis is made, supportive management of airway, breathing and circulation is pivotal. Advanced cardiac life support should be initiated when necessary. Fluid resuscitation and vasopressors can improve cardiac output. Hyperbaric oxygen therapy should be considered when possible in cases of suspected cerebral air embolism cases to improve neurological outcome. A multidisciplinary team approach and effective communication with experts, potentially including an anesthesiologist, cardiologist, intensivist, radiologist and surgeon, can improve the outcome in air embolism.

A case of retrograde venous air embolism causing cerebral infarction following upper gastrointestinal endoscopy: A novel pathophysiological mechanism

The incidence of cerebral infarction following upper gastrointestinal endoscopic procedures is well described in the existing literature, with most mechanisms involving arterial travel of the embolus. We describe a case of cerebral infarction not explained by previously described mechanisms and detail the proposed occurrence of retrograde venous air embolism causing cerebral infarction following an upper gastrointestinal endoscopic procedure.

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.

Cerebral air embolism following an endoscopic variceal ligation: A case report

BACKGROUND

Cerebral air embolism (CAE) is a rare but potentially devastating complication of endoscopic procedures. Only 3 cases, to our knowledge, have been reported.

CASE PRESENTATION

A 50-year-old female patient presented with hepatitis C virus-related hepatic cirrhosis, emergency endoscopy and endoscopic variceal ligation was performed in an awakened state. CAE occurred during procedure, the patient passed away the next day in the intensive care unit.

CONCLUSIONS

CAE is a rare but potentially devastating complication in endoscopic procedures. We need more preventive tools and treatments.

Systemic air embolism complicating upper gastrointestinal endoscopy: a case report with post-mortem CT scan findings and review of literature

Endoscopy of the gastrointestinal and biliary tract is a common procedure and is routinely performed for therapeutic and diagnostic purposes. Perforation, bleeding and infection are some of the more common reported side effects. Air embolism on the other hand, is a rare complication of gastrointestinal endoscopy. We report a 77-year-old African-American female with a history of pancreatic cancer, which was resected with a Whipple procedure. As part of diagnostic and therapeutic procedure, an endoscopic retrograde cholangiopancreatography was planned several months after the surgery. The patient's heart rate suddenly slowed to 40 bpm during the procedure and she became cyanotic and difficult to oxygenate after the endoscope was introduced and CO₂ gas was insufflated. A forensic autopsy was performed with post-mortem computed tomography (PMCT) and revealed extensive systemic air embolism. The detailed PMCT and autopsy findings are presented and current literature is reviewed.

Effects of carbon dioxide insufflation during direct cholangioscopy on biliary pressures and vital parameters: a pilot study in porcine models

BACKGROUND AND AIMS

Direct per-oral cholangioscopy allows endoscopic visualization of the biliary tract. Insufflation with carbon dioxide (CO₂) is an alternative to saline solution irrigation during direct cholangioscopy. There are no data on maximal CO₂ insufflation in direct cholangioscopy without causing biliary barotrauma or fatal gas embolism. We aimed to evaluate the safety of increasing CO₂ insufflation in direct cholangioscopy without causing biliary barotrauma or fatal gas embolism.

METHODS

This was an in vivo animal study. Four domestic pigs, under general endotracheal anesthesia, were used. The first animal was used to validate the feasibility of direct cholangioscopy and biliary pressure measurements, after which all animals underwent laparotomy, insertion of a pressure transducer in the cystic duct, and direct transpapillary placement of the cholangioscope. The common bile duct (CBD) and cystic duct were ligated to contain the instilled gas and exclusively expose the biliary tree. Insufflation of CO₂ started at 200 mL/min and was continuously increased until there was evidence of bile duct rupture (as measured by a drop in intraductal pressures) or instability of vital signs (hypotension, bradycardia, bradypnea, O₂ desaturation). Necropsy was performed on all animals to assess the liver and biliary system for evidence of barotrauma.

RESULTS

CO₂ was insufflated up to 8 L/min without causing bile duct rupture or instability in vital signs despite increasing CBD pressure with insufflation. There was significant correlation between CO₂ flow with partial pressure of CO₂ in arterial blood (PaCO₂) (coefficient, 0.96-1.00; P < .01) and end tidal expired CO₂ (EtCO₂) (coefficient, 0.94-1.00; P < .01). However, the pulse rate, respiratory rate, arterial blood pressure, and O₂ did not correlate with the amount of CO₂ flow. There was no evidence of hepatic or biliary barotrauma on necropsy.

CONCLUSIONS

This pilot experience in porcine models suggests that CO₂ insufflation is safe for direct cholangioscopy and does not result in biliary barotrauma or vital signs instability.

Role of Computed tomography in predicting prognosis of Hepatic portal venous gas

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When hepatic portal venous gas is diagnosed on computed tomography, the first etiology that radiologist should look for is the intestinal necrosis.

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The association of hepatic portal venous gas and pneumatosis intestinalis is highly suggestive of acute mesenteric ischemia.

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Abundance of hepatic portal venous gas on CT is not correlated with prognosis.

Background

The aim of this study was to report through 13 cases the particularities of abdominal computed tomography (CT) aspects of hepatic portal venous gas (HPVG) and its correlation with patient prognosis.

Methods

We analyzed abundance of HPVG and its association with pneumatosis intestinalis (PI) in correlation with fatal outcome using chi-square tests.

Results

Etiologies were mesenteric infarction (n = 5), sigmoid diverticulitis (n =  1), septic shock (n = 1), postoperative peritonitis (n = 1), acute pancreatitis (n = 1), iatrogenic cause (n = 3) and idiopathic after a laparotomy (n = 1). The outcome was fatal in for 6 patients. Abundance of HPV was expressed in total number of hepatic segments involved. The involvement of 3 or more segments was a sensitive sign for lethal outcome with high sensitivity (100%) but it was not specific (50%). Negative predictive value of this sign was 100% (p ≤ 0.005). Positive predictive value of PI for death was 100% (p ≤ 0.001).

Discussion

Abundance of HPVG is correlated with prognosis. The presence of PI announces poor outcome Negative predictive value of presence of HPVG in 3 or more segments is interesting. Predicting prognosis with CT can help surgeons to assess the most adequate treatment. Iatrogenic causes are increasingly described after interventional radiology procedures with favorable course.

Conclusion

The first etiology radiologists should look for in front of HPVG involving more than 3 hepatic segments and associated with PI is intestinal necrosis which announces a poor prognosis. This study shows that outside of shock situations, HPVG involving 2 or less hepatic segments without PI predicts a good outcome.

Carbon dioxide insufflation in esophageal endoscopic submucosal dissection reduces mediastinal emphysema: A randomized, double-blind, controlled trial

AIM

To assess the efficacy of CO₂ insufflation for reduction of mediastinal emphysema (ME) immediately after endoscopic submucosal dissection (ESD).

METHODS

A total of 46 patients who were to undergo esophageal ESD were randomly assigned to receive either CO₂ insufflation (CO₂ group, n = 24) or air insufflation (Air group, n = 22). Computed tomography (CT) was carried out immediately after ESD and the next morning. Pain and abdominal distention were chronologically recorded using a 100-mm visual analogue scale (VAS). The volume of residual gas in the digestive tract was measured using CT imaging.

RESULTS

The incidence of ME immediately after ESD in the CO₂ group was significantly lower than that in the Air group (17% vs 55%, P = 0.012). The incidence of ME the next morning was 8.3% vs 32% respectively (P = 0.066). There were no differences in pain scores or distention scores at any post-procedure time points. The volume of residual gas in the digestive tract immediately after ESD was significantly smaller in the CO₂ group than that in the Air group (808 mL vs 1173 mL, P = 0.013).

CONCLUSION

CO₂ insufflation during esophageal ESD significantly reduced postprocedural ME. CO₂ insufflation also reduced the volume of residual gas in the digestive tract immediately after ESD, but not the VAS scores of pain and distention.

Clinical Evaluation of Hepatic Portal Venous Gas after Abdominal Surgery

Hepatic portal venous gas (HPVG) is induced by various abdominal diseases. Since HPVG is accompanied by bowel ischemia, intestinal infection and hypovolemia, various modes of critical management are needed to treat the underlying conditions. HPVG associated with abdominal complications after surgery has rarely been reported. We present 4 patients with HPVG after abdominal surgery: 2 of the 4 patients died of multiple organ failure, and the other 2 recovered with solely conservative therapy. Although postoperative HPVG is a severe and life-threatening condition, early detection and systemic treatment lead to a better patient outcome.

Paradoxical air embolus during endoscopic retrograde cholangiopancreatography: an uncommon fatal complication

Air embolism during endoscopic retrograde cholangiopancreatography is a rare but potentially fatal complication. A 66-year-old man underwent endoscopic retrograde cholangiopancreatography and remained stable until the end of the procedure, when he was found to have mottling on his right side and became hypoxic and unresponsive. Transesophageal echocardiography showed air within the left ventricle, consistent with systemic air embolism. Mortality resulted from significant cardiac and cerebral ischemia. The literature suggests that capnography is helpful in early diagnosis of air embolus, but it could not be used in this case because the patient's trachea was not intubated.

Safety and efficacy of carbon dioxide insufflation during gastric endoscopic submucosal dissection

AIM: To compare the safety and efficacy of carbon dioxide (CO₂) and air insufflation during gastric endoscopic submucosal dissection (ESD).

METHODS: This study involved 116 patients who underwent gastric ESD between January and December 2009. After eliminating 29 patients who fit the exclusion criteria, 87 patients, without known pulmonary dysfunction, were randomized into the CO₂ insufflation (n = 36) or air insufflation (n = 51) groups. Standard ESD was performed with a CO₂ regulation unit (constant rate of 1.4 L/min) used for patients undergoing CO₂ insufflation. Patients received diazepam for conscious sedation and pentazocine for analgesia. Transcutaneous CO₂ tension (PtcCO₂) was recorded 15 min before, during, and after ESD with insufflation. PtcCO₂, the correlation between PtcCO₂ and procedure time, and ESD-related complications were compared between the two groups. Arterial blood gases were analyzed after ESD in the first 30 patients (12 with CO₂ and 18 with air insufflation) to assess the correlation between arterial blood CO₂ partial pressure (PaCO₂) and PtcCO₂.

RESULTS: There were no differences in respiratory functions, median sedative doses, or median procedure times between the groups. Similarly, there was no significant difference in post-ESD blood gas parameters, including PaCO₂, between the CO₂ and air groups (44.6 mmHg vs 45 mmHg). Both groups demonstrated median pH values of 7.36, and none of the patients exhibited acidemia. No significant differences were observed between the CO₂ and air groups with respect to baseline PtcCO₂ (39 mmHg vs 40 mmHg), peak PtcCO₂ during ESD (52 mmHg vs 51 mmHg), or median PtcCO₂ after ESD (50 mmHg vs 50 mmHg). There was a strong correlation between PaCO₂ and PtcCO₂ (r = 0.66; P < 0.001). The incidence of Mallory-Weiss tears was significantly lower with CO₂ insufflation than with air insufflation (0% vs 15.6%, P = 0.013). CO₂ insufflation did not cause any adverse events, such as CO₂ narcosis or gas embolisms.

CONCLUSION: CO₂ insufflation during gastric ESD results in similar blood gas levels as air insufflation, and also reduces the incidence of Mallory-Weiss tears.

Pulseless electrical activity arrest due to air embolism during endoscopic retrograde cholangiopancreatography: a case report and review of the literature

While most gastroenterologists are aware of the more common complications of endoscopy such as bleeding, infection and perforation, air embolism remains an under-recognised and difficult to diagnose problem due to its varying modes of presentation. This is the case of a 55-year-old man with right upper quadrant pain and imaging notable for cholecystitis and choledocholithiasis, who underwent endoscopic retrograde cholangiopancreatography (ERCP). During the ERCP, and shortly after a sphincterotomy was performed, he became hypotensive and hypoxic, quickly decompensating into pulseless electrical activity. While advanced cardiac life support was initiated, the patient passed away. Autopsy revealed air in the pulmonary artery suggestive of a pulmonary embolism. While air embolism remains a rare complication of upper endoscopy, increased awareness and prompt recognition of signs that may point to this diagnosis may potentially save lives by allowing for earlier possible interventions.

Sudden death after endoscopic retrograde cholangiopancreatography (ERCP)--case report and literature review

There are only a few cases found in literature regarding air embolism in endoscopic procedures, especially in connection to endoscopic retrograde cholangiopancreatography (ERCP). We are presenting a case of a 56-year-old female patient who suffered from non-Hodgkin lymphoma located in her right groin. She was also diagnosed with choledocholithiasis and underwent ERCP to remove the gallstones. Immediately after the procedure she went into sudden cardiac arrest and subsequently died, despite all of our efforts. We reviewed literature in order to identify possible causes of death because fatal outcome following an uneventful and successful procedure was not expected. It is important to bear in mind all possible complications of ERCP. Our focus during the literature search was on air embolism.

Safety of carbon dioxide insufflation during gastric endoscopic submucosal dissection in patients with pulmonary dysfunction under conscious sedation

BACKGROUND

Carbon dioxide (CO2) insufflation is effective for gastric endoscopic submucosal dissection (ESD). However, its safety is unknown in patients with pulmonary dysfunction. This study aimed to investigate the safety of CO2 insufflation during gastric ESD in patients with pulmonary dysfunction under conscious sedation.

METHODS

We analyzed 322 consecutive patients undergoing ESD using CO2 insufflation (1.4 L/min) for gastric lesions. Pulmonary dysfunction was defined as a forced expiratory volume in 1.0 s/forced vital capacity (FEV1.0%) <70% or vital capacity <80%. Transcutaneous partial pressure of CO2 (PtcCO2) was recorded before, during, and after ESD.

RESULTS

In total, 127 patients (39%) had pulmonary dysfunction. There were no significant differences in baseline PtcCO2 before ESD, peak PtcCO2 during ESD, and median PtcCO2 after ESD between the pulmonary dysfunction group and normal group. There was a significant correlation between PtcCO2 elevation from baseline and ESD procedure time (r = 0.22, P < 0.05) only in the pulmonary dysfunction group. In patients with FEV1.0% <60%, the correlation was much stronger (r = 0.39, P < 0.05). Neither the complication incidences nor the hospital stay differed between the two groups. CO2 narcosis or gas embolism was not reported in either group.

CONCLUSIONS

CO2 insufflation during gastric ESD in patients with pulmonary dysfunction under conscious sedation is safe with regard to complication risk and hospital stay. However, in patients with severe obstructive lung disease, especially in those with FEV1.0% <60%, longer procedure time may induce CO2 retention, thus requiring CO2 monitoring.

Cerebral air embolism from angioinvasive cavitary aspergillosis

Background. Nontraumatic cerebral air embolism cases are rare. We report a case of an air embolism resulting in cerebral infarction related to angioinvasive cavitary aspergillosis. To our knowledge, there have been no previous reports associating these two conditions together. Case Presentation. A 32-year-old female was admitted for treatment of acute lymphoblastic leukemia (ALL). Her hospital course was complicated by pulmonary aspergillosis. On hospital day 55, she acutely developed severe global aphasia with right hemiplegia. A CT and CT-angiogram of her head and neck were obtained demonstrating intravascular air emboli within the left middle cerebral artery (MCA) branches. She was emergently taken for hyperbaric oxygen therapy (HBOT). Evaluation for origin of the air embolus revealed an air focus along the left lower pulmonary vein. Over the course of 48 hours, her symptoms significantly improved. Conclusion. This unique case details an immunocompromised patient with pulmonary aspergillosis cavitary lesions that invaded into a pulmonary vein and caused a cerebral air embolism. With cerebral air embolisms, the acute treatment option differs from the typical ischemic stroke pathway and the provider should consider emergent HBOT. This case highlights the importance of considering atypical causes of acute ischemic stroke.

Fatal Cerebral Air Embolism Due to a Patent Foramen Ovale during Endoscopic Retrograde Cholangiopancreatography

Fatal air embolism to the cerebrum during an endoscopic retrograde cholangiopancreatography (ERCP) has not been reported in a patient with a biliodigestive anastomosis and multiresistant extended-spectrum β-lactamase Escherichia coli (ESBL) bacteremia. A 59-year-old woman with a history of laparoscopic cholecystectomy and iatrogenic injury of the right choledochal duct, choledochojejunostomy (biliodigestive anastomosis), recurrent cholangitis, revision of the biliodigestive anastomosis, recurrent liver abscesses, and recurrent stenting of stenotic bile ducts, was admitted because of fever and tenderness of the right upper quadrant. On ERCP, a previously deployed covered Wallstent was replaced. Blood cultures grew ESBL. After stent removal 8 days later, the patient did not wake up and developed arterial hypotension and respiratory insufficiency, requiring mechanical ventilation. Computed tomography scans showed extensive air embolism to the liver, heart, and cerebrum. She died 1 day later. Although the exact pathogenesis of the fatal cerebral air embolism remains speculative, the nonphysiological anatomy and chronic infection with ESBL may have been contributory factors.

Uncommon and rarely reported adverse events of endoscopic retrograde cholangiopancreatography

Endoscopic retrograde cholangiopancreatography (ERCP) has become a primary tool for the treatment of biliary and pancreatic ductal diseases. It is essential for the endoscopist carrying out the ERCP to have a thorough understanding of the potential adverse events. Typically, endoscopists are well familiar with common adverse events such as post-ERCP pancreatitis, cholangitis, post-sphincterotomy bleeding, post-sphincterotomy perforation, and sedation-related cardiopulmonary compromises. However, there are other less common adverse events that arecritical to promptly recognize in order to provide appropriate therapy and prevent disastrous outcomes. This review focuses on the presentation and management of the less common and rare adverse events of an ERCP from the perspective of the practicing endoscopist.

Cardiac Arrest from Asystole During Endoscopic Retrograde Cholangiopancreatography: A Rare But Fatal Complication

We present a rare complication of cardiac arrest from asystole in the setting of prolonged endoscopic retrograde cholangiopancreatography(ERCP) procedure. Cardiopulmonary complications of ERCP are rare but can be fatal. Therefore it is essential to closely monitor the patient during ERCP. Immediate access to resuscitation equipment facilitating prompt intervention in the unlikely event of fatal cardiovascular collapse should be a part of standard ERCP protocol to ensure life threatening complications are appropriately managed.

Venous air embolism: an under-recognized and potentially catastrophic complication in orthopaedic surgery

INTRODUCTION

Venous air embolism (VAE) is the entry of air or other medical gases into the central venous system, producing an air embolism to the right heart or pulmonary artery. VAE is a largely iatrogenic complication with potentially devastating sequelae that can occur in a variety of surgical procedures.

METHOD

Within orthopaedics, VAE has been associated with both open and arthroscopic surgeries with the patient in a variety of positions (ie, prone, supine, sitting). These articles, as well as reports of VAE in other surgical settings outside of orthopaedics, are examined.

CONCLUSION

Diagnosis of VAE requires a high index of suspicion, as clinical presentation ranges from completely asymptomatic to fatal cardiopulmonary collapse. The vigilant surgeon should carefully watch for air entry at the operative site and the astute anesthesiologist must closely monitor end-tidal CO2 (ETCO2). Prevention of VAE is of paramount importance, as management is largely supportive and aimed at inhibiting further air ingress.

Emergencies after endoscopic procedures

Endoscopy adverse events (AEs), or complications, are a rising concern on the quality of endoscopic care, given the technical advances and the crescent complexity of therapeutic procedures, over the entire gastrointestinal and bilio-pancreatic tract. In a small percentage, not established, there can be real emergency conditions, as perforation, severe bleeding, embolization or infection. Distinct variables interfere in its occurrence, although, the awareness of the operator for their potential, early recognition, and local organized facilities for immediate handling, makes all the difference in the subsequent outcome. This review outlines general AEs' frequencies, important predisposing factors and putative prophylactic measures for specific procedures (from conventional endoscopy to endoscopic cholangio-pancreatography and ultrasonography), with comprehensive approaches to the management of emergent bleeding and perforation.

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 potential to be severe and fatal. It can present with cardiopulmonary instability and neurologic symptoms. The diagnosis may be difficult because of its clinical presentation, which can overlap with sedation-related cardiopulmonary 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 cerebral air embolism following endoscopic evaluation of rectal stump

A 63-year-old man underwent endoscopic evaluation of the rectal stump for rectal bleeding and suffered a massive cerebral air embolism with severe neurological impairment and subsequent death. The patient underwent a Hartmann's procedure 9 month previously for ischaemic bowel and was noted to have portal hypertension at laparotomy. We hypothesise that air entered the venous plexus around rectum and entered the azygos vein via a porto-systemic shunt and travelled retrogradely via the superior vena cava to the venous sinuses of the brain.

Endoscopic retrograde cholangiopancreatography complications in the era of cholangioscopy: is there an increased risk?

BACKGROUND

Single-operator cholangioscopy allows direct visualization of the biliary tree and is being used in the diagnosis and treatment of various biliary conditions. To date, there are few data examining complications of single-operator cholangioscopy.

METHODS

We evaluated all endoscopic retrograde cholangiopancreatography procedures over a two-year period and compared its complication rate to single-operator cholangioscopy in a tertiary care centre with extensive experience in single-operator cholangioscopy. A total of 2087 patients (55% men, mean age 57.4±16.4) had a therapeutic endoscopic retrograde cholangiopancreatography, out of which 169 also had single-operator cholangioscopy performed on them.

RESULTS

169 single-operator cholangioscopy procedures were performed (53% men) with a mean patient age of 60.7±15.2 years. Out of the 2087 patients, 160 complications occurred (7.7%), and included pancreatitis (n=47, 2.2%), infection (n=24, 1.1%), bleeding (n=44, 2.1%), perforation (n=16, 0.8%) and other (n=29, 1.4%). Univariate analysis on overall complications identified seven variables with a p value<0.2, which were included in the multivariate analysis. Biliary sphincterotomy, pancreatic duct stent placement, and ampullectomy were associated with increased complications. Single-operator cholangioscopy was not associated with increased complications on multivariate analysis.

CONCLUSION

Single-operator cholangioscopy is not associated with an increased rate of complications when compared to endoscopic retrograde cholangiopancreatography. The types and frequencies of overall endoscopic retrograde cholangiopancreatography complications are similar to previously reported series.

Management of complete esophageal stricture after treatment of head and neck cancer using combined anterograde retrograde esophageal dilation

BACKGROUND

Complete esophageal stricture is a difficult problem to manage. There is limited literature to support clinical decision-making. To evaluate outcomes and efficacy, we performed a retrospective medical chart review of patients who received combined anterograde retrograde esophageal dilation (CARD) between 2002 and 2009 at our institution.

METHODS

Fifteen patients were identified who developed a stricture requiring CARD after treatment for head and neck cancers. Outcomes were pretreatment and posttreatment diet, gastrostomy tube status, and operative complications.

RESULTS

Six of 15 patients were gastrostomy tube-free at last follow-up and 11 of 15 patients were taking oral nutrition. There were 4 complications. One patient died. Two gastrostomy tube site complications occurred. One patient sustained a dental injury.

CONCLUSION

CARD offers benefit to most patients. Despite risks associated with the procedure, CARD should be considered by the clinician and patient in management of complete esophageal stricture.

Cardiac and cerebral air embolism from endoscopic retrograde cholangio-pancreatography

Regional or systemic air embolism to the heart or cerebrum during endoscopic retrograde cholangio-pancreatography (ERCP) is an increasingly recognized phenomenon. This review aims to give an overview about the current knowledge concerning pathomechanism, diagnosis, treatment, and outcome of air embolism during ERCP. A Medline search was carried out for the key words 'ERCP' in combination with 'liver dysfunction', 'air embolism', 'complication', and 'side-effect'. Altogether 18 reports about 19 patients were found matching with the key words and the topic of interest. Systemic air embolism after ERCP occurred in 14 cases and was associated with cerebral air embolism in eight of them. In six cases with cerebral air embolism the outcome was fatal. Only two patients with cerebral air embolism survived, one of them without a deficit and one with hemiparesis. In only two cases, transgression of air from the venous to the arterial branch occurred through a patent foramen ovale. In none of the patients was transgression attributable to arterio-venous shunts within the lung or other tissues, the Thebesian veins, or insertion of the caval veins directly into the left atrium. In five patients, systemic air embolism occurred in the absence of a foramen ovale. In all these cases it was assumed that air entered the vasculature through the portal or hepatic veins. In conclusion, if patients do not awake after ERCP air embolism should be considered, an acute cerebral and thoracic computed tomography scan should be ordered, and appropriate measures, including aspiration of air from the right ventricle through an acutely floated pulmonary artery catheter or hyperbaric oxygenation initiated.