Obstructive Shock Research Articles

Life-Threatening Complications of Hormonal Contraceptives: A Case History

We present a case with the rare combination of thrombotic and hemorrhagic complications of oral contraceptives. A healthy 40-year-old woman suffered from cardiac arrest due to massive pulmonary embolism, caused by oral contraceptives and immobilization during a flight. After successful resuscitation, obstructive shock necessitated thrombolysis and thereafter heparin. Anticoagulation was complicated by internal bleeding from contraceptive related hepatic adenoma. She underwent arterial embolisation, and anticoagulation was continued. On day 18, she was discharged in a good condition. Hepatic adenomas are a potential source of internal bleeding in women using oral contraceptives requiring anticoagulation. Signs of internal bleeding in such patients should prompt immediate abdominal ultrasound examination.

Caval Sonography in Shock

onography has traditionally been used to assess anatomic abnormalities. However, its value in evaluating physiologic characteristics has recently been recognized, particularly in the care of patients in shock. As the use of point-of-care sonography grows in critical care and emergency medicine, noninvasive assessment of intravascular volume status is increasingly being used to guide therapy of the critically ill. Although intravenous fluid is often the initial treatment in hypotensive patients, aggressive volume resuscitation may be detrimental in some patients and in certain types of shock. Accurate diagnosis of shock state can be challenging because physical findings of hypovolemic, distributive, cardiogenic, and obstructive shock often overlap. Pulmonary artery and central venous pressure catheters, which provide physiologic data such as cardiac output and right atrial pressure, are time-consuming, invasive, and carry considerable risks. Central venous pressure has long been used to guide fluid management; however, data suggest that in critically ill patients, central venous pressure may not correlate with the effective intravascular volume. 1 Furthermore, invasive hemodynamic monitoring has not been shown to benefit patients. 2 Given the importance of determining intravascular volume in shock, a rapid bedside sonographic examination can be instrumental in guiding medical management of critically ill patients. Multiple sonographic protocols now exist for the evaluation of shock, dyspnea, and cardiac arrest. 3,4 This article will describe the use of sonography of the inferior vena cava (IVC) in the evaluation of patients in shock.

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Introduction: Acute Massive Pulmonary Embolism (AMPE) is defined as venous thromboembolism (VTE) with associated obstructive shock due to acute right ventricular failure. Previous studies have shown that 70% of patients expire within 1 hour of symptom onset. Given the clinical course, rapid diagnosis and risk stratification are critical. Little is known about the utility of right ventricular echocardiography (RVE) for risk stratification in AMPE. Hypothesis: We hypothesized that advanced RVE parameters would provide prognostic information in patients with AMPE. Methods: We retrospectively reviewed all Maine Medical Center discharge records of patients with PE occurring between January 2010 and June 2012 to obtain demographic and clinical data. RVE measurements were obtained by analysis of echocardiograms performed prior to VTE therapy at the time of AMPE initial presentation. Group differences were considered statistically significant at p < 0.05. This study was approved by the Maine Medical Center Institutional Review Board. Results: There were 287 patients with PE of which AMPE was diagnosed in 46 cases (16%). Cardiac arrest was the initial presentation in 19.5% of cases. Overall AMPE mortality was 39.1% with a median time from shock to death of 19.9 hrs. Risk of death was associated with older age (65 vs 57 yrs; p = 0.013) and absence of limb symptoms (RR = 3.5; p = 0.049). Echocardiograms were of adequate quality to obtain RV size and functional parameters in 34 cases. Risk of death was associated with higher tricuspid regurgitation velocity (4.1 vs 2.9 m/s; p = 0.001), higher RV systolic pressure (79.5 vs 45.4 mmHg; p = 0.001) and higher RV/LV diastolic area ratio (2.38 vs 1.04; p = 0.013). Reduced risk of death was associated inferior vena cava (IVC) filter placement (RR = 0.51; p = 0.013). Conclusions: We found AMPE has a rapid clinical course and high mortality. Bedside RVE measurements of TRV, RVSP, and RV/LV diastolic area ratio obtained before VTE therapy have prognostic value in AMPE patients. IVC filter placement may help to reduce overall AMPE mortality. Early bedside RV echocardiography may be of utility in therapeutic decision making.

Abstract 9893: Preoperative Lower Cholesterol Level is the Independent Risk Factor of Severe Postoperative Mortality in Patients With Ruptured Abdominal Aortic Aneurysm

Background: Hypocholesterolemia is reported to be the critical risks of hemorrhagic stroke, but the influence of hypocholesterolemia on large vessels such as abdominal aortic aneurysm (AAA) is unknown. Methods: We conducted a retrospective cohort study on 1053 consecutive patients receiving the surgical repair for infrarenal AAA in multicenter in Tokyo from 2003 through 2011. Laboratory data including total cholesterol levels were measured immediately before surgery. Cox hazards model were used to evaluate the risk factors for the postoperative mortality as well as major adverse cardiac events (MACE; composite of cardiovascular death without postoperative in-hospital death, acute coronary syndrome, cerebrovascular disorder). Results: The average follow-up period was 2.5 ± 2.1 years. In the multiple Cox analysis adjusted for age, gender, aneurysm size, smoking, hypertension, diabetes, past history of coronary disease, past history of chronic obstructive pulmonary disease, anemia, shock, statin use, β-blocker use and angiotensin II receptor blocker use, anemia (hemoglobin level &lt; 10 g/dl), shock and hypocholesterolemia (total cholesterol level &lt; 120 mg/dl) before surgery were found to be the risk factors of all postoperative death in patients with ruptured AAA (HR3.3; 95%CI 2.0-5.3, HR2.5; 95%CI 2.0-4.7, HR;5.4 CI 3.0-9.7, respectively, n=183). Meanwhile, there found to be no risk factor of all death in non-ruptured AAA (n=870). Furthermore, the mortality of patients with each total cholesterol level 120 - 140, 140 - 160, and 160 - 180 mg/dl was higher than that of total cholesterol level &gt; 180 mg/dl (HR3.2; 95%CI 1.9-5.2, HR2.7; 95%CI 1.6-4.4, HR1.8; 95%CI 1.0-3.2, respectively). Receiver operator characteristic (ROC) curve analysis showed hypocholesterolemia is the most significant predictor of postoperative in-hospital death in patients with ruptured AAA (the area under the ROC curve = 0.77). The risk factor of MACE was identified to be the existence of preoperative coronary artery disease. Conclusions: The risk factors of poor mortality in patients with ruptured AAA were anemia, shock and hypocholesterolemia. The lower total cholesterol level indicated the more severe mortality of ruptured AAA.

Right Atrial Metastasis of Uterine Leiomyosarcoma Causing Obstructive Shock

Uterine leiomyosarcomas are rare tumours, and secondary cardiac metastases are even rarer. We present the case of a 56-year-old ethnic Chinese woman who was being treated with adjuvant pelvic radiation for uterine leiomyosarcoma when she presented with signs of right heart failure and shock. She was rapidly diagnosed with a solid mass attached to the tricuspid valve. Subsequent surgical resection revealed leiomyosarcoma metastasis. Metastases of uterine leiomyosarcoma to the heart are extremely rare, but clinicians should be aware of this phenomenon. Surgical resection, when feasible, can be associated with longer survival.

SUDDEN CARDIAC ARREST DURING PREGNANY: A RARE COMPLICATION OF ACQUIRED MATERNAL DIAPHRAGMATIC HERNIA

Acute cardiac arrest during pregnancy is a rare but devastating event. Major causes are haemorrhagic, septic or anaphylactic shock, trauma, pulmonary or amniotic fluid embolism, and congenital or acquired cardiac disease. We present a case of massive intrathoracic migration of viscera through a left diaphragmatic hernia in a pregnant multipara, causing acute obstructive shock and cardiac arrest.Complications of intrathoracic herniation occur when the intruding viscera cause left lung and cardiac compression or mediastinal “tamponade” with decreased venous return. Intrathoracic strangulation of viscera is also common and may cause ischaemia, gangrene and eventual perforation. Sudden cardiac arrest as first sign of left diaphragmatic rupture during pregnancy, however, has rarely been described. In contrast with our patient, this catastrophic event is mostly seen in nulli-and primipara with a known congenital left diaphragmatic defect. Management of a diaphragmatic hernia depends on the clinical presentation and the period of gestation during which it is detected. Despite prolonged resuscitation with more than 1 hour of chest compressions, our patient recovered completely.

Fluid administration limited by lung sonography: the place of lung ultrasound in assessment of acute circulatory failure (the FALLS-protocol)

The FALLS-protocol is included in a limited investigation to diagnose the cause of shock. After simple echocardiography has ruled out obstructive shock (tamponade, pulmonary embolism), the lung is investigated. Absence of disseminated lung rockets rules out cardiogenic shock. At this point, hypovolemic and septic shock are differential diagnoses (rarities apart), and the FALLS-protocol provides fluid therapy with constant monitoring of lung artifacts. Hypovolemic shock will eventually improve – septic shock will not, and the slight excess fluid creates an early, silent stage of interstitial edema, demonstrated by B-lines, demanding interruption of fluid therapy. This sequential approach, combined with the usual, clinical, biochemical and echocardiographic parameters, must be evaluated in multicenter studies.

Retrospective Analysis of Contrast-Enhanced Computed Tomographic Findings Related to Obstructive Shock Due to Ascending Aortic Dissection

The objective of this study was to evaluate contrastenhanced computed tomography findings related to obstructive shock due to ascending aortic dissection (AAD). The computed tomography findings in 9 AAD patients with shock, 11 AAD patients without shock, and 18 control subjects were evaluated for (1) pericardial effusion, (2) diameter of the inferior vena cava, (3) periportal hypodensity, (4) retrograde reflux of contrast material, (5) aortic and visceral enhancement, and (6) other factors (peripancreatic edema, bowel thickening/dilatation). Patients with shock showed the highest ratio of pericardial effusion, periportal hypodensity, and retrograde reflux of contrast material; largest inferior vena cava diameter; stronger aortic enhancement in both the arterial and portal phases; lowered splenic and pancreatic enhancement in the arterial phase; and stronger visceral (especially adrenal) enhancement, except for the renal medulla in the portal phase. Computed tomography findings related to obstructive shock due to AAD reflected impaired diastolic filling, decreased cardiac output, and flow redistribution in visceral organs.

Modified Emergency Department Thoracotomy for Postablation Cardiac Tamponade

Cardiac dysrhythmias are a common problem in the United States. Radiofrequency ablation is being used more frequently as a treatment for these diagnoses. Although rare, serious complications such as cardiac tamponade have been reported as a result of ablation procedures. Traditionally, emergency department (ED) thoracotomy has been reserved for cases of traumatic arrest only. We report a case of a successful modified ED thoracotomy in a patient with postablation cardiac tamponade and subsequent obstructive shock who failed intravenous fluid resuscitation, pressor administration, and multiple attempts at pericardiocentesis. In this case, a modified approach was used to incise the pericardium. Although this was associated with large blood loss, we believed that using the traditional method of completely removing the pericardium would have resulted in uncontrolled hemorrhage. Instead, our method led to successful resuscitation of the patient until definitive care was available. A smaller pericardial incision than is traditionally used during ED thoracotomy deserves further consideration and research to determine whether and when it may be most useful as a temporizing treatment of cardiac tamponade when other methods have failed.

Unexpected bilateral massive pulmonary embolism

A 59-year-old woman with a past history of rheumatoid arthritis arrived in our Emergency Department via ambulance. Her husband stated she had suddenly appeared very strange whilst preparing to go out for the afternoon, but could not identify specific symptoms. Physical examination showed her to have sinus tachycardia and tachypnea, but little else of note. Her oxygen saturations however rapidly dropped when she was taken off high-flow oxygen. Her d-dimer assay was markedly elevated, and urgent computed tomographic pulmonary angiography (CTPA) was performed (Figures 1 and 2). This showed large emboli (black arrows) in both the left (Figure 1) and right (Figure 2) pulmonary arteries (white arrows), with a saddle embolus noted on the right. Following the CTPA, she developed signs and symptoms of obstructive shock, requiring urgent thrombolysis using tenectaplase and admission to the intensive care unit. Her hospital stay was complicated by a lower respiratory tract infection but she was discharged seventeen days after her admission.

Cardiac tamponade

To re-emphasize the epidemiology, pathophysiology, diagnosis, and treatment of cardiac tamponade. Cardiac tamponade is a cause of obstructive shock. Incidence of cardiac tamponade is poorly documented. In cardiac tamponade, the pericardial pressure may reach 15-20 mmHg, leading to an equalization of pressures into the cardiac chambers and to a huge decrease in the systemic venous return. The right atrial transmural pressure becomes negligible. A competition between the right atrium and the right ventricle and between both ventricles is occurring. Deep inspiration allows the patients to maintain the systemic venous return at a certain level. Echocardiography is the key tool to diagnose a pericardial effusion, to detect its bad-tolerance, and to guide the treatment. In some situations following cardiac surgery, transesophageal echocardiography is mandatory. Treatment aims to restore a 'normal' blood pressure by fluid loading (with caution) and catecholamines and to drain the pericardium in emergency. Cardiac tamponade is responsible for an obstructive shock. Causes of pericardial effusion are numerous. Echocardiography is the fundamental tool for the diagnosis and therapeutic management. Volume resuscitation and catecholamines are temporary treatments, pericardial drainage remaining the only effective treatment.

High Flow Oxygen and Low Dose Inhaled Nitric Oxide in a Case of Severe Pulmonary Hypertension and Obstructive Shock

INTRODUCTION: Inhaled nitric oxide (iNO2) is an effective pulmonary vasodilator in treatment of pulmonary hypertension. Prior studies demonstrated a decrease in pulmonary arterial pressure and pulmonary vascular resistance and increase in cardiac output at a dosage between 20-80ppm. However, the effect of lower dosage in conjunction with high flow oxygen has not been well-studied.

A Real Case of Obstructive Shock

EA: Paciente de sexo femenino, de 84 anos, hipertensa, dislipemica, sin antecedentes cardiovasculares, que se acerca a la guardia con un cuadro de disnea progresiva, ortopnea y nicturia de 30 dias de evolucion. Al ingreso, se constatan rales crepitantes bilaterales hasta campos medios. – Radiografia de torax: muestra un ICT aumentado, un arco aortico prominente y un mediastino ensanchado (Figura 1). – Ecocardiograma: ritmo sinusal, sin signos de isquemia aguda y sobrecarga ventricular izquierda. – Ecografia: diametros y FSVI conservados. HVI moderada a grave. Se realiza balance negativo con mala respuesta, tendencia a la hipotension y oliguria, con requerimiento de inotropicos. – Ecografia de control: FSVI conservado; se visualiza una compresion extrinseca de la auricula izquierda. – Tomografia computarizada de torax: (Figuras 2 y 3) que evidencia hernia hiatal paraesofagica gigante, con compromiso de cavidades cardiacas.

Embolia pulmonar quase fatal, um modelo experimental

Experimental studies on pulmonary embolism (PE) are usually performed under mechanical ventilation. Most patients with suspicion of PE enter the Emergency Services in spontaneous breathing and environmental air. Thus, under these conditions, measurements of hemodynamic, gasometric and capnographic variables contribute largely to a more specific comprehension of cardiopulmonary and gasometric alterations in the acute phase of the disease. Studies which evaluated animals under conditions are lacking. This study aimed to submit animals under spontaneous ventilation and without supplemental oxygen to PE. PE was induced in six pigs using autologous blood clots, and cardiorespiratory and gasometric records were performed before and after PE. The values of "near fatal" mean pulmonary arterial pressure (MPAP) were previously determined. The presence of obstructive shock could be evidenced by increased MPAP (from 17.8 ± 3.5 to 41.7 ± 3.3 mmHg) (P<0.0001) and decreased cardiac output (from 4.9 ± 1.0 to 2.7 ± 1.0 L/min) (P<0.003). Consequently, metabolic acidosis occurred (Lac art) (from 2.4 ± 0.6 to 5.7 ± 1.8 mmol/L)(P<0.0001). It was observed hypoxemia (from 73.5 ± 12.7 to 40.3 ± 4.6 mmHg) (P<0.0001); however, PaCO2 did not vary (from 44.9 ± 4.4 to 48.2 ± 6.0 mmHg) (NS). There were significant increases in both P(a-et)CO2 (from 4.8 ± 2.8 to 37.2 ± 5.8 mmHg) and P(A-a)O2 (from 8.2 ± 8.9 to 37.2 ± 10.3 mmHg) (both P<0.0001). There was also a significant increase in the total alveolar minute volume (from 4.0 ± 0.9 to 10.6 ± 2.9 L/min) (P<0.0001). In this model, the near fatal MPAP was from 2 to 2.5 times the basal MPAP; and the capnographic variables, associated with arterial and venous gasometry, showed effective in discriminating an acute obstructive profile.

Part 14: Pediatric Advanced Life Support

In contrast to adults, cardiac arrest in infants and children does not usually result from a primary cardiac cause. More often it is the terminal result of progressive respiratory failure or shock, also called an asphyxial arrest. Asphyxia begins with a variable period of systemic hypoxemia, hypercapnea, and acidosis, progresses to bradycardia and hypotension, and culminates with cardiac arrest.1 Another mechanism of cardiac arrest, ventricular fibrillation (VF) or pulseless ventricular tachycardia (VT), is the initial cardiac rhythm in approximately 5% to 15% of pediatric in-hospital and out-of-hospital cardiac arrests;2,–,9 it is reported in up to 27% of pediatric in-hospital arrests at some point during the resuscitation.6 The incidence of VF/pulseless VT cardiac arrest rises with age.2,4 Increasing evidence suggests that sudden unexpected death in young people can be associated with genetic abnormalities in myocyte ion channels resulting in abnormalities in ion flow (see “Sudden Unexplained Deaths,” below). Since 2010 marks the 50th anniversary of the introduction of cardiopulmonary resuscitation (CPR),10 it seems appropriate to review the progressive improvement in outcome of pediatric resuscitation from cardiac arrest. Survival from in-hospital cardiac arrest in infants and children in the 1980s was around 9%.11,12 Approximately 20 years later, that figure had increased to 17%,13,14 and by 2006, to 27%.15,–,17 In contrast to those favorable results from in-hospital cardiac arrest, overall survival to discharge from out-of-hospital cardiac arrest in infants and children has not changed substantially in 20 years and remains at about 6% (3% for infants and 9% for children and adolescents).7,9 It is unclear why the improvement in outcome from in-hospital cardiac arrest has occurred, although earlier recognition and management of at-risk patients on general inpatient units …

Cardiac Tamponade as Manifestation of Rickettsial Infection

INTRODUCTION: Rapidly fatal septic shock is well known with rickettsiae that do not grow on routine cultures and require different antibiotics. We describe here a case of septic and obstructive shock due to rickettsial infection that manifested with an atypical presentation (without rash).

Prosthetic Mitral Valve Thrombosis Presented as a Pulmonary Embolism with Obstructive Shock in Emergency Department~!2009-11-05~!2010-02-10~!2010-04-22~!

Prosthetic Mitral Valve Thrombosis Presented as a Pulmonary Embolism with Obstructive Shock in Emergency Department~!2009-11-05~!2010-02-10~!2010-04-22~!

Misdiagnosed acute aortic dissection type A

In the absence of diagnostic imaging, chest pain can represent a diagnostic dilemma, especially, if the patient’s condition requires immediate action. We present a case of a patient with signs of obstructive shock that turned out to result from an acute aortic dissection (AAD) and consequent cardiac tamponade. Before the correct diagnosis was made, myocardial infarction and/or pulmonary embolism were suspected and the patient was treated with antithrombotic and anticoagulant drugs, which are contraindicated in AAD. We discuss the correct procedures and treatment in suspected AAD.

Obstructive shock in a 47 year old female with a deep venous thrombosis due to intravascular leiomyomatosis: a case report

IntroductionIntra cardiac tumours and tumour thrombi can present in a manner resembling a massive pulmonary embolism. Intravascular leiomyomatosis with intracardiac extension is one such rare tumour. Survival from obstructive shock in this condition has not been previously reported.Case presentationA case is presented of a female who presented with recurrent syncope, cyanosis and then circulatory shock. An intravascular and intracardiac mass was suspected. Due to refractory shock, she ultimately underwent single stage median sternotomy and exploratory laparotomy, with excision of an intravascular leiomyoma.ConclusionIntravascular leiomyoma with intracardiac extension should be suspected in the differential diagnosis of a female with a history of uterine fibroids or hysterectomy and presenting with right heart obstructive symptoms.

Index of Suspicion in the Nursery

Index of Suspicion in the Nursery