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

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

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

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

Pulmonary barotrauma in SCUBA diving-related fatalities: a histological and histomorphometric analysis.

Arterial gas embolism following pulmonary barotrauma occurs in 13-24% of cases of diving deaths. The study aimed to evaluate the usefulness of a histomorphometric digital analysis in the detection of air space over-distension due to pulmonary barotrauma. The study was performed on lung parenchyma specimens of 12 divers: six had died due to arterial gas embolism following pulmonary barotrauma (mean age at death of 54 years, range of 41-61 years), and six had drowned in saltwater without a diagnosis of pulmonary barotrauma (mean age at death of 54 years, range of 41-66 years) (positive controls). For negative controls, six cases of non-SCUBA divers (mean age of death of 42 years, range of 23-55 years) who died of intracerebral haemorrhage were evaluated. No significant differences were observed in the characteristics of the air spaces between control groups (positive and negative). However, differences were observed in the area occupied by air spaces and the percentage of air space area when we compared the case group to the controls (p < 0.01); and there was a slight difference in the maximum and minimum diameters of air space (p < 0.05). The mean area occupied by air spaces and the mean percentage of air space were the most useful for discriminating pulmonary barotrauma from other causes of death (100% sensitivity and 91.7% specificity). Based on our study, inclusion of an increased pattern of air spaces as a possible diagnostic criterion for pulmonary barotrauma would be useful in discerning the cause of diving death.

Air embolism in CT-guided transthoracic needle biopsy: emphasis on pulmonary vein injury.

OBJECTIVE: To assess whether pulmonary vein injury is detectable on CT and associated with air embolism after percutaneous transthoracic needle biopsy (PTNB) in a tertiary referral hospital. METHODS: Between January 2012 and November 2021, 11,691 consecutive CT-guided PTNBs in 10,685 patients were retrospectively evaluated. Air embolism was identified by reviewing radiologic reports. Pulmonary vein injury was defined as the presence of the pulmonary vein in the needle pathway or shooting range of the cutting needle with the presence of parenchymal hemorrhage. The association between pulmonary vein injury and air embolism was assessed using logistic regression analysis in matched patients with and without air embolism with a ratio of 1:4. RESULTS: A total of 27 cases of air embolism (median age, 67 years; range, 48-80 years; 24 men) were found with an incidence of 0.23% (27/11,691). Pulmonary vein injury during the procedures was identifiable on CT in 24 of 27 patients (88.9%), whereas it was 1.9% (2/108) for matched patients without air embolism The veins beyond the target lesion (70.8% [17/24]) were injured more frequently than the veins in the needle pathway before the target lesion (29.2% [7/24]). In univariable and multivariable analyses, pulmonary vein injury was associated with air embolism (odds ratio, 485.19; 95% confidence interval, 68.67-3428.19, p <.001). CONCLUSION: Pulmonary vein injury was detected on CT and was associated with air embolism. Avoiding pulmonary vein injury with careful planning of the needle pathway on CT may reduce air embolism risk. KEY POINTS: • Pulmonary vein injury during CT-guided biopsy was identifiable on CT in most of the patients (88.9% [24/27]). • The veins beyond the target lesion (70.8% [17/24]) were injured more frequently than the veins in the needle pathway before the target lesion (29.2% [7/24]). • Avoiding the distinguishable pulmonary vein along the pathway or shooting range of the needle on CT may reduce the air embolism risk.

Complications After Transthoracic Needle Biopsy of Pulmonary Nodules: A Population-Level Retrospective Cohort Analysis.

OBJECTIVE: To provide recent population-based estimates of transthoracic needle biopsy (TTNB) complications and risk factors associated with these complications. METHODS: This retrospective cohort analysis included adults from a nationally representative longitudinal insurance claims data set who underwent TTNB in 2017 or 2018. Complications that were evaluated included pneumothorax, hemorrhage, and air embolism. Separate logistic regression models estimated the association of pneumothorax or hemorrhage with the setting of care (ie, inpatient or outpatient) and selected baseline patient demographic and clinical characteristics including age, gender, history of chronic obstructive pulmonary disease, diagnosis of pleural effusion, tobacco use, use of oral anticoagulants and antiplatelet agents, prior lung cancer screening, previous bronchoscopy within 1 year, and Elixhauser comorbidity index. RESULTS: Among 16,971 patients who underwent TTNB, 25.8% experienced a complication within 3 days of the procedure (pneumothorax 23.3%, hemorrhage 3.6%, and air embolism 0.02%). Among patients who experienced pneumothorax, 31.9% required chest tube drainage. Among patients undergoing an outpatient TTNB (n = 12,443), 6.9% were hospitalized within 7 days. Biopsy in an inpatient setting, chronic obstructive pulmonary disease diagnosis, and prior bronchoscopy were associated with higher rates of both pneumothorax and hemorrhage. Prior lung cancer screening was associated with an increased risk of pneumothorax, and prior use of oral anticoagulants or antiplatelets was associated with higher rates of hemorrhage. CONCLUSION: This contemporary population-based cohort study demonstrated that approximately one-quarter of patients undergoing TTNB experienced a complication. Pneumothorax was the most frequent complication, and hemorrhage and air embolism were rare. Among outpatients, complications from TTNB are an important cause of hospitalization.

Fatal systemic (paradoxical) air embolism diagnosed by postmortem funduscopy.

Air embolism is often unrecognized and underreported. Published case reports or case series describe only rare fundal examinations of retinal air emboli (RAE)-a distinctive sign of systemic air embolism. We report an infant, found unresponsive at home, who died in the emergency department after unsuccessful resuscitative efforts. Before the autopsy, diagnostic RAE were recognized and imaged during postmortem funduscopy. Postmortem radiography and an autopsy confirmed systemic (paradoxical) air embolism due to inflicted abdominal and thoracic blunt force injuries. While a few descriptions and illustrations of RAE occur in case reports, we found no published photographic images of RAE in infants, children, or adults. This case report describes and photographically documents classic RAE associated with fatal systemic (paradoxical) air embolism. Complementing postmortem radiography and judicious autopsy techniques, the detection of RAE can aid pathologists in diagnosing systemic air embolism.

Rectal explosion: a strange case of autoerotic death.

Autoerotic deaths refer to fatalities occurring during individual, solitary sexual activity, in which some device, situation, or act is used to gain or boost the sexual arousal of the subject. Anorectal autoeroticism is an autoerotic paraphilic activity that pertains to the self-insertion of various objects into the anal canal and rectal cavity to gain or heighten the subject's sexual drive. Although most foreign bodies inserted into the rectum do not cause significant injury, the introduction of some objects into the rectum might have unpredictable and even fatal effects. In this paper, we describe an intriguing autoerotic case of a 35-year-old male who sustained an explosive rectal trauma as a result of the unanticipated bursting of an expandable rubber pipe stopper that he inserted into his rectum and hyperinflated via an air blow gun connected through a pressure pipe to a centralized air-distribution system. The man sustained a circular abruption of the rectum with partial avulsion of the abdominal wall, associated with bleeding into the abdominal cavity and chest wall, and died before admission to the hospital. A police investigation revealed that the victim was a regular contributor to several web forums dedicated to unusual sexual activities. This case raises awareness of the broadening spectrum of methods and experiments associated with autoerotic behavior. We also reviewed the literature pertaining to this topic and outlined some of the characteristics of atypical autoerotic deaths. Although certain autoerotic methods are relatively common, other unusual autoerotic techniques may present novel challenges within the medicolegal field.

Potentially fatal complications of systemic air embolism after computed tomography-guided transthoracic needle biopsy in lung cancer harboring epithelial growth factor receptor mutation: A case report.

Air embolism is a rare, fatal complication of computed tomography (CT)-guided transthoracic needle biopsy (TTNB) of the lung. Here, we report a patient who developed an air embolism after CT-guided TTNB, which led to ST-elevation myocardial infarction and acute cerebral ischemia. The patient recovered completely without critical sequelae and was diagnosed with adenocarcinoma harboring activating epidermal growth factor receptor (EGFR) mutation. The patient responded to subsequent treatment with gefitinib. KEY POINTS: SIGNFICANT FINDINGS OF THE STUDY: Air embolism is a rare, fatal complication of CT-guided transthoracic lung biopsy. Only a few cases have been previously reported where myocardial and cerebral infarction occurred after TTNB, demonstrated not only on CT scan, but also electrocardiogram and electroencephalogram. WHAT THIS STUDY ADDS: Detection of driver gene mutation is crucial for planning lung cancer treatment. Despite the need for tissue biopsy, air embolism propagation to vital organs could result in severe end-organ damage and multidisciplinary approaches are needed to improve initial outcomes.

Massive gas embolisms in diving fatalities visualized by radiology and neuropathology.

Massive vascular gas embolism is a feared and often lethal symptom of decompression illness, resulting from diving accidents. The aim of this case report was to correlate post-mortem computed tomography scan (PMCT) findings with autopsy in cases of massive vascular gas embolism. Two cases of fatal diving accidents were retrospectively selected from a forensic radiological pathological database. The PMCT results were initially shared with the forensic pathologist prior to autopsy, enabling a more accurate overall assessment. Both cases were in retrospect thoroughly studied to compare the PMCT findings with the autopsy results. In general, intra- and extra-vascular gas collections are easily detected on PMCT in all body regions. We focused on abundant intravascular gas collections, mainly in the large brain vessels. General autopsy findings are described in both cases, and in one case we elaborate on specific intracerebral changes found at autopsy. Both cases were diagnosed as pulmonary barotrauma with subsequent vascular gas embolisms. We conclude that PMCT excels in the detection of macroscopic gas collections in the body, whereas microscopic gas collections identified at autopsy aid in the differentiation between decompression sickness and pulmonary barotrauma followed by vascular gas embolism. The presented cases highlight the advantages of using both PMCT and autopsy in the post-mortem evaluation of fatal diving accidents.

Lessons of the month 1: Fatal oesophago-pericardial fistula with cerebral air embolism after elective atrial fibrillation ablation.

Oesophago-pericardial fistula following any electrophysiological procedure is a rare, and potentially, life-threatening condition. Initial presentation can easily be misdiagnosed, as symptoms vary and are not specific. Echocardiography is an invaluable tool to diagnose and rule out complications. We present the case of a 68-year-old patient who developed an oesophago-pericardial fistula complicated with purulent pericarditis, sepsis and cerebral air embolism. In conclusion, this case report encourages physicians to use strategies that may help with early diagnosis and lead to potential lifesaving interventions.

Air contamination during medical treatment results in deposits of microemboli in the lungs: An autopsy study.

INTRODUCTION: Microbubbles of air may enter into patients during conventional hemodialysis, infusions of fluids, or by injections. The aim of this study was to investigate whether the air that enters the patient during hemodialysis can be detected in the lungs after death, and if so, whether this may be related to tissue damage. METHODS: The material consisted of lung tissue from five chronic hemodialysis patients who died either during (two) or after hemodialysis (range 10 min from start until 3333 min after the last hemodialysis session); as reference group tissue was taken from seven patients who died due to amyotrophic lateral sclerosis. The lung tissue was investigated by microscopy after autopsy using a fluorescein-marked polyclonal antibody against fibrinogen as a marker for clots preformed before death. RESULTS: All five hemodialysis patients had microbubbles of air in the lung tissue, whereas two of seven amyotrophic lateral sclerosis patients had such findings (Fisher's test p = 0.0278, relative risk = 3.5, confidence interval: 1.08-11.3). There were more microbubbles of air/10 randomly investigated microscopic fields of tissue in the hemodialysis patients than the amyotrophic lateral sclerosis patients (Student's test, p < 0.05). All hemodialysis patients had a medium graded extent of pulmonary fibrosis that was not found in any of the ALS patients. The microbubbles of air were surrounded by fibrin as a sign of development of clots around the air bubbles while the patients were still alive. CONCLUSION: Exposure to microbubbles of air during various treatments such as hemodialysis may result in microemboli. Future studies should clarify whether microbubbles of air contribute to tissue scarring. We suggest preventive measures against the exposure to microbubbles of air during especially repeated exposures such as hemodialysis.

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.

Fatal air embolism in hospital confirmed by autopsy and postmortem computed tomography.

Vascular air embolism is caused by penetration of air into veins or arteries through a surgical wound or other connection between the external and internal aspects of the body. Vascular air embolism has various causes, and iatrogenic air embolisms are the most frequently described. We report a case of fatal air embolism in an 83-year-old woman who was admitted to hospital. At the time of the incident, she was alone in her ward receiving an intravenous infusion of antibiotics via a peripheral line in her right forearm. She was also inhaling air through a mask, which was connected via a tubing system to a compressed air connection in the wall behind her bed. Autopsy and postmortem computed tomography (PMCT) findings are presented. The case illustrates the high diagnostic value of PMCT, which is an effective procedure for detecting the presence of air or gas.

Fatal air embolism following local anaesthetisation: does needle size matter?

A 76--year--old male cigarette smoker presented with a 2-week history of cough and haemoptysis. Chest CT on admission revealed multiple new lung nodules concerning for malignancy. CT--guided biopsy of the nodule in left lower lobe was attempted in prone oblique position for tissue diagnosis. Local anaesthetic (lidocaine) was administered using a 25--gauge (1.5-inch) needle to anaesthetise the skin and subcutaneous tissue. This was followed by insertion of a 25-gauge (3.5-inch) Whitacre needle to anaesthetise deeper tissues and parietal pleura. Due to patient's coughing and proximity of the nodule to the diaphragm, the circumstances were judged to be too risky for a needle biopsy. Therefore, it was decided to biopsy another nodule in the left lung that was visible on the same CT section. During this portion of the procedure, the patient became hypoxic and developed pulseless electrical activity arrest. Cardiopulmonary resuscitation was unsuccessful and the efforts ceased after 45 min. Subsequent review of CT scan revealed air in the left ventricle.

Gas embolism as a potential cause of death by helium poisoning - Postmortem computed tomography changes in two cases of suicidal helium inhalation.

Evaluation of two suicidal helium inhalation cases is presented, comprising both conventional autopsy methods and postmortem computed tomography. Conventional postmortem examinations reveal no characteristic changes. Modern diagnostic techniques enabled to disclosethe presence of a very large amount of accumulated gas in all examined areas, including veins and arteries of the head, torso, lower extremities, heart chambers, and between muscle fibers in both cases. The changes due to possible putrefaction were taken into consideration - radiological alteration index was calculated. In forensic literature, the reported mechanism of death in helium poisoning is rapid asphyxiation due to oxygen deprivation. However, papers on clinical cases and animal studies with the use of helium report development of gas in body cavities and lethal gas embolism, comprehensible when we take into account the specific physical properties of helium: high permeability and very low solubility in blood. The results reported by the authors are consistent with massive gas embolism similar to changes presentedin cases of decompression illness. They suggest this as the cause of death in helium inhalation cases. Undoubtedly, this requiresconfirmation in further observations, taking into account differentiating diagnosis of air embolism versus oxygen deprivation.

Diagnosis of arterial gas embolism in SCUBA diving: modification suggestion of autopsy techniques and experience in eight cases.

The purpose of this study was to suggest modifications of autopsy techniques in order to improve post-mortem diagnosis of arterial gas embolism (AGE) based on multidisciplinary investigation of SCUBA diving fatalities. Five adult human cadavers from the voluntary donation program of the Human Anatomy Laboratory, and eight judicial autopsied bodies of SCUBA divers from the Forensic Pathology Service were assessed. Before performing any autopsies, we accessed the diving plan and the divers' profiles for each case. We then introduced a new dissection procedure that included identification, isolation, and manipulation of carotid, vertebral and thoracic arterial systems. The dissected vascular structures that allowed optimall isolation of the systemic arterial circulation were identified and ligated. In three of the eight judicial cases, we had a strongly suggestive history of arterial gas embolism following pulmonary barotrauma (PBt/AGE). In these cases, the additional arterial dissection allowed us to clearly diagnose AGE in one of them. The autopsy of the rest of the cases showed other causes of death such as asphyxia by drowning and heart attack. In all cases we were able to reject decompression sickness, and in some of them we showed the presence of artefacts secondary to decomposition and resuscitation maneuvers. These results allow us to suggest a specific autopsy technique divided into four steps, aimed at confirming or excluding some evidence of dysbaric disorders according to a re-enactment of the incident. We have demonstrated the presence of large volumes of intravascular air, which is typical of PBt/AGE.

A Case of Fatal Cerebral Air Embolism After Blunt Lung Trauma: Postmortem Computed Tomography and Autopsy Findings.

Cerebral air embolism is caused by gas bubbles in the vascular system. These bubbles can cause cerebral ischemia by obstructing encephalic blood vessels. It is frequently associated with blunt and penetrating chest trauma as well as iatrogenic interventions. Lung trauma involving laceration of the respiratory tract, lung parenchyma, and blood vessels may result in direct communication of these structures, driving air or gas into the pulmonary venous system. We report a case of a blunt chest trauma that led to massive arterial air embolism that was possible to recognize with the help of postmortem computed tomographic scan examination.

Cerebral Air Embolism: A Clinical, Radiologic and Histopathologic Correlation.

Cerebral air embolism is a recognized life-threatening complication, sometimes iatrogenic. Its timely diagnosis is essential because it can result in neurologic deficits or death. We report a case of a 58-year-old man who died from cerebral air embolism diagnosed by nonenhanced computed tomography scan of the head after a cardiac bypass surgery with Biventricular Assist Device and multiple vascular line placements. Autopsy revealed extensive subcutaneous emphysema, intravascular and perivascular air bubbles in the central nervous system and associated cerebral and cerebellar hemorrhagic infarction. The autopsy was helpful in documenting the extent of the air embolism and its appearance in soft tissue and central nervous system.