Acute caval thrombosis leading to obstructive shock in the early post insertion period of an inferior vena cava filter: a case report and literature review.

BACKGROUND: Obstructive shock is extremely rare in clinical practice and is caused by acute blood flow obstruction in the central vessels of either the systemic or pulmonary circulation. Utilizing inferior vena cava filters (IVCFs) to prevent pulmonary embolism (PE) is associated with some potential complications, such as inferior vena cava thrombosis (IVCT). Shock as a direct result of IVCT is rare. We present a case of obstructive shock secondary to extensive IVCT caused by inadequate anticoagulant therapy after the placement of an IVCF. CASE PRESENTATION: A 63-year-old male patient with a traffic accident injury presented orthopaedic trauma and lower limb deep vein thrombosis (DVT). He experienced sudden and severe abdominal pain with hypotension, tachycardia, tachypnea, oliguria and peripheral oedema 5 days after IVCF placement and 3 days after cessation of anticoagulant therapy. Considering that empirical anti-shock treatment lasted for a while and the curative effect was poor, we finally recognized the affected vessels and focused on the reason for obstructive shock through imaging findings-inferior vena cava thrombosis and occlusion. The shock state immediately resolved after thrombus aspiration. The same type of shock occurred again 6 days later during transfer from the ICU to general wards and the same treatment was administered. The patient recovered smoothly in the later stage, and the postoperative follow-up at 1, 3, and 12 months showed good results. CONCLUSION: This case alerts clinicians that it is crucial to ensure adequate anticoagulation therapy after IVCF placement, and when a patient presents with symptoms such as hypotension, tachycardia, and lower limb and scrotal oedema postoperatively, immediate consideration should be given to the possibility of obstructive shock, and prompt intervention should be based on the underlying cause.

A Guide to the Use of Vasopressors and Inotropes for Patients in Shock.

Shock is a life-threatening circulatory failure that results in inadequate tissue perfusion and oxygenation. Vasopressors and inotropes are vasoactive medications that are vital in increasing systemic vascular resistance and cardiac contractility, respectively, in patients presenting with shock. To be well versed in using these agents is an important skill to have in the critical care setting where patients can frequently exhibit symptoms of shock. In this review, we will discuss the pathophysiological mechanisms of shock and evaluate the current evidence behind the management of shock with an emphasis on vasopressors and inotropes.

Veno-arterial extracorporeal membrane oxygenation uses in trauma: a retrospective analysis of the Japanese nationwide trauma registry.

BACKGROUND: Extracorporeal membrane oxygenation (ECMO) can provide temporary circulatory support and vital organ oxygenation and is potentially useful as a bridge therapy in some trauma cases. We aimed to demonstrate the characteristics and outcomes of patients with trauma treated with veno-arterial ECMO (V-A ECMO) using data from a Japanese nationwide trauma registry. METHODS: This retrospective descriptive study analyzed data from the Japan Trauma Data Bank between January 2019 and December 2021. Patients with severe trauma (injury severity score [ISS] ≥ 9) and treated using V-A ECMO were assessed. RESULTS: Among the 72,439 patients with severe trauma, 51 received V-A ECMO. Sixteen patients (31.3%) survived until hospital discharge. On hospital arrival, six (37.5%) survivors and 15 (42.9%) non-survivors experienced cardiac arrest. The median ISS for the survivor and non-survivor group was 25 (range, 25-39) and 25 (range, 17-33), respectively. Thoracic trauma was the most common type of trauma in both groups. In the non-survivor group, open-chest cardiopulmonary resuscitation, aortic cross-clamping, and resuscitative endovascular balloon occlusion of the aorta were performed in 10 (28.6%), 5 (14.3%), and 4 (11.4%) patients, respectively. However, these procedures were not performed in the survivor group. Peripheral oxygen saturation tended to be lower in the survivor group both before and upon arrival at the hospital. CONCLUSIONS: The results of this study suggest the potential benefit of V-A ECMO in some challenging trauma cases. Further studies are warranted to assess the indications for V-A ECMO in patients with trauma.

Diagnostic accuracy of point-of-care ultrasound for shock: a systematic review and meta-analysis.

BACKGROUND: Circulatory failure is classified into four types of shock (obstructive, cardiogenic, distributive, and hypovolemic) that must be distinguished as each requires a different treatment. Point-of-care ultrasound (POCUS) is widely used in clinical practice for acute conditions, and several diagnostic protocols using POCUS for shock have been developed. This study aimed to evaluate the diagnostic accuracy of POCUS in identifying the etiology of shock. METHODS: We conducted a systematic literature search of MEDLINE, Cochrane Central Register of Controlled Trials, Embase, Web of Science, Clinicaltrial.gov, European Union Clinical Trials Register, WHO International Clinical Trials Registry Platform, and University Hospital Medical Information Network Clinical Trials Registry (UMIN-CTR) until June 15, 2022. We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and assessed study quality using the Quality Assessment of Diagnostic Accuracy Studies 2 tool. Meta-analysis was conducted to pool the diagnostic accuracy of POCUS for each type of shock. The study protocol was prospectively registered in UMIN-CTR (UMIN 000048025). RESULTS: Of the 1553 studies identified, 36 studies were full-text reviewed, and 12 studies with 1132 patients were included in the meta-analysis. Pooled sensitivity and specificity were 0.82 [95% confidence interval (CI) 0.68-0.91] and 0.98 [95% CI 0.92-0.99] for obstructive shock, 0.78 [95% CI 0.56-0.91] and 0.96 [95% CI 0.92-0.98] for cardiogenic shock, 0.90 [95% CI 0.84-0.94] and 0.92 [95% CI 0.88-0.95] for hypovolemic shock, and 0.79 [95% CI 0.71-0.85] and 0.96 [95% CI 0.91-0.98] for distributive shock, respectively. The area under the receiver operating characteristic curve for each type of shock was approximately 0.95. The positive likelihood ratios for each type of shock were all greater than 10, especially 40 [95% CI 11-105] for obstructive shock. The negative likelihood ratio for each type of shock was approximately 0.2. CONCLUSIONS: The identification of the etiology for each type of shock using POCUS was characterized by high sensitivity and positive likelihood ratios, especially for obstructive shock.

Obstructive Shock, from Diagnosis to Treatment.

Shock is a life threatening pathological condition characterized by inadequate tissue oxygen supply. Four different subgroups of shock have been proposed according to the mechanism causing the shock. Of these, obstructive shock is characterized by reduction in cardiac output due to noncardiac diseases. The most recognized causes include pulmonary embolism, tension pneumothorax, pericardial tamponade and aortic dissection. Since obstructive shock typically cannot be stabilized unless cause for shock is resolved, diagnosis of the underlying disease is eminent. In this review, we therefore focus on diagnosis of obstructive shock and suggest a structured approach in three steps including clinical examination, ultrasound examination using the rapid ultrasound in shock (RUSH) protocol and radiological imaging if needed.

An unusual etiology of obstructive shock in the emergency department.

Obstructive shock describes any disease process that causes physical obstruction to blood flow into or out of the heart which results in impaired systemic oxygen or nutrient delivery. Common etiologies include cardiac tamponade, tension pneumothorax, and pulmonary embolus. However, several other causes exist and should prompt consideration in the correct clinical circumstances. In this report, we describe a 72-year-old female patient with history of hepatic cysts presenting with respiratory distress, mottled extremities, and abnormal vital signs. Contrast enhanced computed tomography scans showed a massive hepatic cyst which was compressing her vena cava and heart, causing hemodynamic instability. The patient was admitted to the ICU and the hepatic cyst was drained percutaneously, but ultimately, she succumbed to her illness post-operatively. This report highlights the importance of keeping a broad differential when considering etiologies of undifferentiated shock as well as the need for additional research regarding management of rare causes of obstructive shock.

Resuscitation from Cardiac Arrest with Tension Gastrothorax Due to Acquired Diaphragmatic Hernia.

Tension gastrothorax is a rare cause of obstructive shock induced by a distended stomach herniating into the thorax through a diaphragmatic defect. We report the process of diagnosis and emergency treatment for tension gastrothorax during cardiopulmonary resuscitation (CPR). A 71-year-old woman with multiple surgical histories had nausea and vomiting for two days. She was transferred to our hospital with circulatory failure and loss of consciousness. She presented pulseless electric activity and received CPR immediately after arrival. The right atrium and right ventricle were collapsed in the echocardiography. A chest X-ray demonstrated a dilated intestine extending from the peritoneal cavity to the mediastinum. The nasogastric tube (NGT) drained 1000 mL of stomach content and alleviated the abdominal distension, and spontaneous circulation returned immediately after the drainage. Thoracoabdominal CT showed the stomach and the transverse colon had escaped from the peritoneal cavity to the mediastinum. We diagnosed the situation as tension gastrothorax due to an acquired diaphragmatic hernia. History of multiple surgery and multiple operative scars was the first step of the diagnostic process, and the chest X-ray during CPR was the key to the diagnosis. Tension gastrothorax can be misdiagnosed as other conditions. A chest X-ray should be preceded in non-trauma settings, unlike the setting of a tension pneumothorax in trauma patients. Gastrointestinal decompression with NGT placement could be attempted quickly to improve the hemodynamic condition.

Obstructive shock due to right ventricular compression by a massively expanded reconstructed gastric tube.

Obstructive shock is often associated with poor right ventricular (RV) output and requires rapid obstruction release. A 54-year-old man was brought to our emergency department, presenting with shock. He had previously undergone esophagectomy with gastric interposition through the retrosternal route, after which he could not eat solid foods. After eating a ball of rice, he became critically ill, with a significantly increased lactate level, an indicator of shock. Though initial examinations showed no abnormalities, he was hospitalized for observation. The following day, he experienced similar discomfort while in the supine position, an hour after breakfast. Cardiac sonography revealed that the RV was remarkably compressed by a massively expanded gastric tube, causing diastolic dysfunction. After propping him into a sitting position, he recovered from shock. Upon a second examination of CT images, we recognized the massively dilated gastric tube compressing the RV. Anatomically, the retrosternal route is located directly in front of the RV. Thus, it is thought that the massively dilated gastric tube externally compressed the RV, preventing adequate RV filling and causing the obstructive shock. In such cases, the patient's position should be changed immediately to release the RV compression.

[Prehospital treatment of tension pneumothorax in children-which decisions do we make? : Results of a survey among German emergency physicians]. / Die prähospitale Therapie eines Spannungspneumothorax bei Kindern ­ welche Entscheidungen treffen wir? : Ergebnisse einer Umfrage unter deutschen Notärzten.

BACKGROUND: The preclinical treatment of a traumatic or spontaneous tension pneumothorax remains a particular challenge in pediatric patients. Currently recommended interventions for decompression are either finger thoracostomy or needle decompression. Due to the tiny intercostal spaces, finger thoracostomy may not be feasible in small children and surgical preparation may be necessary. In needle decompression, the risk of injuring underlying vital structures is increased because of the smaller anatomic structures. As most emergency physicians do not regularly work in pediatric trauma care, decompression of tension pneumothorax is associated with significant uncertainty; however, in this rare emergency situation, consistent and goal-oriented action is mandatory and lifesaving. An assessment of pre-existing experience and commonly used techniques therefore seems necessary to deduce the need for future education and training. OBJECTIVE: In this study an online survey was created to evaluate the experience and the favored prehospital treatment of tension pneumothorax in children among German emergency physicians. MATERIAL AND METHODS: An online survey was conducted with 43 questions on previous experience with tension pneumothorax in children, favored decompression technique and anatomical structures in different age groups. Surveyed were the emergency physicians of the ground-based emergency medical service of the University Medical Center Mannheim, the German Air Rescue Service (DRF) and the pediatric emergency medical service of the City of Munich. RESULTS: More than half of all respondents stated that there was uncertainty about the procedure of choice. Needle decompression was favored in smaller children and mini-thoracostomy in older children. In comparison with the literature, the thickness of the chest wall was mostly estimated correctly by the emergency medical physicians. The depth of the vital structures was underestimated at most of the possible insertion sites in all age groups. At the lateral insertion sites on the left hemithorax, however, the distance to the left ventricle was overestimated. The caliber of the needle selected for decompression tended to be too large, especially in younger children. CONCLUSION: Even though having interviewed an experienced group of prehospital emergency physicians, the experience in decompression of tension pneumothorax in children is relatively scant. Knowledge of chest wall thickness and depth to vital structures is sufficient, the choice of needle calibers tends to be too large but still reasonable. For many providers a large amount of uncertainty about the right choice of technique and equipment arises from the challenge of decompressing a tension pneumothorax in children and therefore further theoretical education and regular training are required for safe performance of the procedure.

Diagnosing obstructive shock: Echocardiography is the third eye of a vigilant intensivist.

Training in echocardiography is essential for an intensivist. We present a rapidly fatal case of obstructive shock where a vigilant intensivist could diagnose left atrial mass obstructing the mitral inflow as the etiology of shock.

Prompt Diagnosis of an Unusual Cause of Obstructive Shock Using Point-of-Care Ultrasound.

BACKGROUND: The patient presenting in an undifferentiated shock state can produce a diagnostic challenge for even the most seasoned clinician. CASE REPORT: We present an unusual case of an elderly woman in obstructive shock from a large atrial mass that was promptly diagnosed with point-of-care ultrasound. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Ultrasound is a non-invasive tool that can help facilitate the early diagnosis of a patient in undifferentiated shock.

Extracorporeal Life Support Use in Mixed Distributive-Obstructive Shock Following an Electrical Injury: A Case Report.

Electrical burn injuries can be catastrophic, threatening severe disability or mortality. We present a patient who suffered from electrical shock, requiring bilateral above-knee amputations, right trans-radial amputation, renal replacement therapy, and veno-arterial extracorporeal life support (VA ECLS) therapy. While there exist reports of cases that have demonstrated the potential use of ECLS in burn patients with cardiogenic shock or acute respiratory distress syndrome, this is a unique case of VA ECLS use for an electrical injury patient who developed mixed distributive-obstructive shock secondary to pulmonary embolism and sepsis. Given the wide variety of morbidities that can result from electrical burns, VA ECLS is a promising tool for those who require cardiopulmonary support refractory to traditional measures.

The physiology of cardiac tamponade and implications for patient management.

Exceeding the limit of pericardial stretch, intrapericardial collections exert compression on the right heart and decrease preload. Compensatory mechanisms ensue to maintain hemodynamics in the face of a depressed stroke volume but are outstripped as disease progresses. When constrained within a pressurized pericardial space, the right and left ventricles exhibit differential filling mediated by changes in intrathoracic pressure. Invasive hemodynamics and echocardiographic findings inform on the physiologic effects. In this review, we describe tamponade physiology and implications for supportive care and effusion drainage.

Relief of Obstructive Shock with a Large Hiatal Hernia Occupying the Posterior Mediastinum by Urgent Endoscopy.

A 78-year-old man was admitted to our hospital with obstructive shock caused by a large hiatal hernia that occupied the posterior mediastinum. Tension gastro-duodenothorax was detected in his stomach and duodenum, and we performed urgent endoscopy to relieve shock. Large hiatal hernia occasionally leads to cardiac failure. This is the first reported use of urgent endoscopy to treat a large hiatal hernia.

Re-enforcing High-Risk Acute Pericarditis Requiring Hospital Admission: An Unusual Case of Critical Idiopathic Acute Pericarditis Presenting As Tamponade and Pleuro-Pericardial Complications in a Patient Presenting With Flu-Like Symptoms.

Pericarditis is an inflammatory process that affects the pericardium, the fibrous sac surrounding the heart. Acute pericarditis accounts for approximately 0.1% of inpatient admissions and 5% of non-ischemic chest pain visits to the emergency departments (EDs). Most patients who present with acute pericarditis have a benign course and good prognosis. However, a rare percent of the patients develop complicated pericarditis. Examples of complications include pericardiac effusion, cardiac tamponade, constrictive pericarditis, effusive and constrictive pericarditis and, even more rarely, large pleural effusion The occurrence of complicated pericarditis can lead to high morbidity and mortality if not urgently managed in most patients. Our case presents a 60-year-old male that presented to the emergency room with flu-like symptoms. However, the viral panel test was negative. He initially got discharged with supportive care but was brought back to the ED by his wife in a critical, life-threatening state due to pericarditis symptoms complicated by tamponade and shock. His condition required urgent intervention and critical level of care. The patient's course was also complicated by myopericarditis and recurrent bilateral pleural effusions, which required therapeutic interventions. This unique case presents the patient group that develop multiple life-threatening complications of acute pericarditis, including cardiac tamponade and shock, affecting several end organs. This case also highlights clues to the predisposing factors to complications of acute pericarditis. Patients who present with high-risk signs and symptoms indicating poorer prognosis warrant further observation and admission. This will also add to the literature reviews regarding the risk factors associated with development of complicated acute pericarditis. This will also serve as a review of pathophysiology, etiology, current diagnosis and available novel treatment for such patients.

Cardiac Tamponade Caused by Campylobacter ureolyticus Purulent Effusion.

A male in his 60s presented to the emergency department with a seven-day history of progressively worsening malaise, dyspnea, nausea, and vomiting. The patient quickly developed septic and obstructive shock, with the ensuing investigation significant for a purulent pericardial effusion causing cardiac tamponade. Subsequent cultures grew Campylobacter ureolyticus, which is commonly associated with the gastrointestinal tract and is one of many microorganisms that cause diarrhea. Yet, studies have identified this pathogenic organism in oral infections, infectious meningitis, and soft tissue infections, but not pericardial effusions. This organism is an emerging pathogen and warrants renewed research efforts.

Obstructive Shock Due to a Crushed Left Atrium and Pulmonary Vein by Pulmonary Artery Intimal Sarcoma Successfully Treated with Pulmonary Vein Stenting.

A 46-year-old patient who had undergone right pneumonectomy for pulmonary artery intimal sarcoma presented with hypoxemia. The recurrent sarcoma in the mediastinum revealed external compression to the left pulmonary veins (PVs), leading to obstructive shock and cardiac arrest. Venous artery extracorporeal membrane oxygenation (VA-ECMO) was initiated; however, withdrawal was difficult, and the patient's survival seemed hopeless. However, the patient's condition improved with stenting for the compressed PV; therefore, VA-ECMO was discontinued, and he was discharged on foot. This is the first case report of obstructive shock due to critical PV stenosis caused by compression of a malignant tumor that responded to PV stenting.

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

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

Management Strategies for Acute Pulmonary Embolism in the ICU.

TOPIC IMPORTANCE: Acute pulmonary embolism (PE) is a common disease encountered by pulmonologists, cardiologists, and critical care physicians throughout the world. For patients with high-risk acute PE (defined by systemic hypotension) and intermediate high-risk acute PE (defined by the absence of systemic hypotension, but the presence of numerous other concerning clinical and imaging features), intensive care often is necessary. Initial management strategies should focus on optimization of right ventricle (RV) function while decisions about advanced interventions are being considered. REVIEW FINDINGS: We reviewed the existing literature of various vasoactive agents, IV fluids and diuretics, and pulmonary vasodilators in both animal models and human trials of acute PE. We also reviewed the potential complications of endotracheal intubation and positive pressure ventilation in acute PE. Finally, we reviewed the data of venoarterial extracorporeal membrane oxygenation use in acute PE. The above interventions are discussed in the context of the underlying pathophysiologic features of acute RV failure in acute PE with corresponding illustrations. SUMMARY: Norepinephrine is a reasonable first choice for hemodynamic support with vasopressin as an adjunct. IV loop diuretics may be useful if evidence of RV dysfunction or volume overload is present. Fluids should be given only if concern exists for hypovolemia and absence of RV dilatation. Supplemental oxygen administration should be considered even without hypoxemia. Positive pressure ventilation should be avoided if possible. Venoarterial extracorporeal membrane oxygenation cannulation should be implemented early if ongoing deterioration occurs despite these interventions.

Left Atrial Compression by an Intramural Hematoma: A Rare Case of Obstructive Shock.

A 3.5 cm diameter descending aorta focal aneurysm was incidentally found when a computed tomography (CT) was conducted due to persistent pyrexia in an 85-year-old woman hospitalized for a non-obstructive urinary tract infection. Ten days later, whilst fever subsided and inflammation markers decreased, she became hypoxic. CT revealed an aortic intramural hematoma (Stanford type B) increasing the diameter of the thoracic aorta aneurysm to 6.5 cm. A thoracic endovascular aortic repair (TEVAR) surgery was performed. Seven days after the operation she developed respiratory and hemodynamic compromise. CT depicted further enlargement of the aortic intramural hematoma, increasing the aortic diameter to 8 cm. Transthoracic echocardiography provided valuable information showing extrinsic compression of the left atrium and left ventricle inflow obstruction provoking obstructive shock.