Aortic emergencies

Acute aortic dissection is without any doubt the most feared and life threatening aortic emergency. It is associated with a dreadful mortality rate and an immediate and accurate diagnosis without delay followed by adequate treatment is mandatory. It is important to make a distinction between acute type A, uncomplicated and complicated type B. Acute type A dissection generally requires urgent surgery, complicated type B dissections are treated with endovascular techniques; there is ongoing debate whether uncomplicated type B dissections should also be treated by endografts in its early phase. Surgical repair of acute type A dissection consists of the replacement of the intrapericardial ascending aorta with varying segments of the arch and/or aortic root. The endovascular techniques with stentgrafts deployed into the proximal descending aorta in type B dissections have revolutionized the surgical therapy and the patient�s immediate and medium-term survival. For chronic postdissection aneurysms open surgery still remains the golden standard. Acute traumatic aortic isthmus ruptures are similar life threatening conditions and account for one of the main causes of death at the time of traumatic accidents. In these situations also stentgrafts have changed the outcome of these severe and multiple traumatic patients.

Pericardiocentesis

Pericardiocentesis, the percutaneous drainage of the pericardial effusion, is the technique of choice for the treatment of cardiac tamponade. In addition, it could be useful for diagnostic purposes in specific situations. The pericardial puncture could be associated to serious complications and as it could be performed in a wide variety of clinical settings, from an emergency to a programmed diagnostic procedure, it is mandatory for the clinician to know how to plan and how to safely perform the procedure. This chapter will deal with indications, contraindications, different approaches, complications and periprocedural management of the pericardiocentesis procedure.

Donor organ management

Organ transplantation is the standard treatment modality for end-stage organ disease in selected cases. Two types of potential organ donors can be identified: the brain-dead 'heart-beating donors', referred to as DBD (donation after brain death), and the warm ischaemic 'non-heart-beating donors', referred to as DCD (donation after circulatory death). Brain death induces several physiological changes in the DBD donor. An autonomic storm is characterized by massive catecholamine release, followed by autonomic depletion during a vasoplegic phase. This is associated with several hormonal changes (suppression of vasopressin, the hypothalamic-pituitary-adrenal axis, and the hypothalamic-pituitary-thyroid axis) and an inflammatory response. These physiological changes form the basis of organ donor management, including cardiovascular stabilization and hormonal therapy (including vasopressin and analogues, thyroid hormone, and cortisol). Donor management is the continuation of critical care, with a shift towards individual organ stabilization. An aggressive approach to maximize organ yield is recommended; however, many treatment strategies need further investigation in large randomized trials. DCD donors have now evolved as a valid alternative to increase the potential donor pool and challenge the clinician with new questions. Optimal donor comfort therapy and end-of-life care are important to minimize the agonal phase. A strict approach towards the determination of death, based on cardiorespiratory criteria, is prerequisite. Novel strategies have been developed, using ex situ organ perfusion as a tool, to evaluate and recondition donor organs. They might become more important in the future to further optimize organ quality.

Special considerations in the immunosuppressed patient

Because of improved treatment of haematological malignancies, autoimmune diseases, and HIV infection, an increasing number of patients are being immunocompromised. Immunosuppression varies according to the underlying disease, and different patterns of complications may be encountered. Among the complications of immunosuppressive treatments, infectious diseases are the most frequently encountered, but drug-related toxicities and secondary neoplasms have to be recognized. Making a rapid diagnosis is the most important step in taking these patients in charge. In such setting, cardiac involvement is severe and often leads to admission to intensive care units. This chapter will focus on the cardiac complications of immunosuppression, from heart transplantation to HIV treatment-related toxicity and cardiac infections.

Computerized tomography: coronary angiography and cardiac imaging

Patients presenting with chronic and acute chest pain constitute a common and important diagnostic challenge. This has increased interest in using computerized tomography for non-invasive visualization of coronary artery disease in patients presenting with acute chest pain to the emergency department, particularly the subset of patients who are suspected of having an acute coronary syndrome, but without typical electrocardiographic changes and with normal troponin levels at presentation. As a result of rapid developments in coronary computerized tomography angiography technology, high diagnostic accuracies for excluding coronary artery disease can be obtained. It has been shown that these patients can be discharged safely. The accuracy for detecting a significant coronary artery stenosis is also high, but the presence of coronary artery atherosclerosis or stenosis does not imply necessarily that the cause of the chest pain is related to coronary artery disease. Moreover, non-invasive detection of coronary artery disease by computerized tomography has been shown to be related with an increased use of subsequent invasive coronary angiography and revascularization, and further studies are needed to define which patients benefit from invasive evaluation following coronary computerized tomography angiography. Conversely, implementation of coronary computerized tomography angiography can significantly reduce the length of hospital stay, with a significant cost reduction. Additionally, computerized tomography is an excellent modality in patients whose symptoms suggest other causes of acute chest pain such as aortic aneurysm, aortic dissection, or pulmonary embolism. Furthermore, acquisition of the coronary arteries, thoracic aorta, and pulmonary arteries in a single computerized tomography examination is feasible, allowing ‘triple rule-out’ (exclusion of aortic dissection, pulmonary embolism, and coronary artery disease). Finally, other applications, such as evaluation of coronary artery plaque composition, myocardial function and perfusion, and non-invasive assessment of fractional flow reserve from coronary computerized tomography angiography, are currently being developed and may also become valuable in the setting of chronic and acute chest pain in the future.

Pulmonary embolism

Pulmonary embolism is usually a consequence of deep vein thrombosis, and together the two conditions are known as venous thromboembolism. Non-thromboembolic causes of pulmonary embolism are rare. Pulmonary thromboembolism is a potentially life-threatening disease, if left untreated. This is due to a natural tendency towards early recurrence of pulmonary emboli which may lead to fatal right ventricular failure. In more severe cases, secondary right ventricular failure may result from myocardial ischaemia and injury caused by systemic hypotension and adrenergic overstimulation. Clinical presentation of pulmonary embolism is non-specific and may include dyspnoea, chest pain, haemoptysis, syncope, hypotension, and shock. Patients with suggestive history, symptoms, and signs require an immediate triage which determines further management strategy. Computerized tomographic angiography has become the mainstay of diagnosis. However, depending on the clinical presentation, treatment decisions may also be made based on results of other tests. In particular, in high-risk patients with persistent hypotension or shock, bedside echocardiography may be the only available test to identify patients in need of primary thrombolysis, surgical embolectomy, or percutaneous intervention which will stabilize the systemic cardiac output. For most normotensive patients, anticoagulation is sufficient as initial treatment. However, in the presence of signs of right ventricular dysfunction and myocardial injury monitoring is recommended to allow prompt rescue reperfusion therapy in case of haemodynamic decompensation.

Ethical issues in cardiac arrest and acute cardiac care: a European perspective

Acute cardiac syndromes are common and responsible for considerable mortality and morbidity. Decision making in such patients can be difficult clinically but can also be complex and challenging from an ethical perspective. This chapter reviews some of the ethical problems, including organ donation and withholding/withdrawing, that can occur in the acutely ill adult cardiac patient, starting with a brief look at the ethical principles that should guide our decision making: beneficence, non-maleficence, autonomy, and distributive justice. The role of advance directives and considerations related to family presence during cardiopulmonary resuscitation will also be discussed. With the increasing incidence and prevalence of coronary artery disease worldwide, the number of patients with cardiac arrest and requiring acute cardiac care is going to increase, and doctors will increasingly be faced with difficult ethical decisions associated with these patients. Open discussion and debate about these issues and good communication among patients, family members, and members of the health care team are essential to ensure that all patients receive the best possible end-of-life care.

Ultrasound-guided vascular access in intensive/acute cardiac care

Acid-base homeostasis is vital for the maintenance of normal tissue and organ function, as both acidosis and alkalosis can have harmful and potentially life-threatening effects on the human body. Arterial blood gas analysis, combined with routine clinical history and examination, can provide useful information for the management of the critically ill cardiac patient. Most acid-base derangements are reversed by treatment of the underlying disease process, rather than simple correction of the abnormal pH, and prognosis is determined by the nature of the underlying disease, rather than the extent of pH value deviation. Within this chapter, an approach is presented for prompt and accurate acid-base interpretation. Water and electrolyte disorders are common in the intensive cardiac care unit, particularly in patients with cardiac failure. Prompt recognition and treatment is required to prevent cardiovascular and neurological compromise. Therapeutic strategies range from simple electrolyte substitution and fluid management to extracorporeal filtration of excess fluid and electrolytes. These are discussed within this chapter.

Atrial fibrillation and supraventricular arrhythmias

The term supraventricular tachycardia (SVT) refers to atrial arrhythmias, including atrial fibrillation, atrioventricular nodal reentry, and atrioventricular reentry due to accessory pathway(s). In clinical practice, SVT may present as narrow- or wide-QRS tachycardias, and with the potential exception of atrial fibrillation, most of them are usually, although not invariably, manifest as regular rhythms. They are usually intrusive, symptomatic, and anxiety provoking but not dangerous. However, depending on their cycle length and the patient's background, they could also be, rarely, life-threatening conditions. In the acute setting, consideration of epidemiology data, clinical presentation, and the 12 lead ECG can provide diagnostic clues for differential diagnosis between SVT and ventricular arrhythmias, and guide appropriate therapy.

Quality of care assessment in acute cardiac care

This chapter will describe the use of performance measures and quality measures in the assessment of the quality of care delivered to patients with acute cardiovascular disease. It gives a brief recap of the major landmarks in the development of the use of performance measures, and goes on to explain the different approaches to measuring processes of care and to measuring outcomes. The utility and construction of composite measures is also described.