1. Discuss the anatomy of the middle mediastinum?
middle mediastinum, which consists of the pericardium and heart.
2. Describe the pericardium and mention its nerve supply?
Taha lecture slides 3 and 5
3. What are the structures that can be affected by cardiomegaly? the lungs and heart are occupy the mediastinum delicately. And the lung is a passive pressure sensitive organ. So the increase in heart size (usually in LV) will variably effect the lung function which will be compressed decreasing the exercise capacity or even cause dyspnea 4. Discuss the causes and pathogenesis of pericardial effusion? Clinical manifestations of pericardial effusion are highly dependent on the rate of accumulation of fluid in the pericardial sac. Rapid accumulation of pericardial fluid may cause elevated intrapericardial pressures with as little as 80 mL of fluid, while slowly progressing effusions can grow to 2 L without symptoms. Understanding the properties of the pericardium can help to predict changes within the heart under physiologic stress. By distributing forces across the heart, the pericardium plays a significant role in the physiologic concept of ventricular interdependence, whereby changes in pressure, volume, and function in one ventricle influence the function of the other. The pericardium plays a pivotal role in cardiac changes during inspiration. Normally, as the right atrium and ventricle fill during inspiration, the pericardium limits the ability of the left-sided chambers to dilate. This contributes to the bowing of the atrial and ventricular septums to the left, which reduces left ventricular (LV) filling volumes and leads to a drop in cardiac output. As intrapericardial pressures rise, as occurs in the development of a pericardial effusion, this effect becomes pronounced, which can lead to a clinically significant fall in stroke volume and eventually progress to the development of pericardial tamponade. The pericardium plays a beneficial role during hypervolemic states by limiting acute cardiac cavitary dilatation. 5. What are the types of fluid that can be detected by cytological
examination in pericardial effusion?
n imbalance between the pressure within blood vessels (which drives fluid out of the blood vessel) and the amount of protein in blood (which keeps fluid in the blood vessel) can result in accumulation of fluid (called a transudate). Transudates are most often caused by congestive heart failure or cirrhosis. If the fluid is determined to be a transudate, then usually no more tests on the fluid are necessary. Injury or inflammation of the pericardium may cause abnormal collection of fluid (called an exudate). Exudates are associated with a variety of conditions and diseases and several tests, in addition to the initial ones performed, may be used to help diagnose the specific condition, including: 1 Infectious diseases – caused by viruses, bacteria, or fungi. Infections may originate in the pericardium or spread there from other places in the body. For example, pericarditis may follow a respiratory infection. 2 Bleeding – bleeding disorders and/or trauma can lead to blood in the pericardial fluid. Inflammatory conditions – pericarditis may follow a heart attack, radiation treatment, or be part of autoimmune disorders such as rheumatoid arthritis and systemic lupus erythematosus.
6. What are the other investigations used in diagnosis of pericardial
effusion ? Chest Radiography: findings in chest radiography include an enlarged cardiac silhouette (so-called water-bottle heart) and a pericardial fat stripe. One third of patients have a coexisting pleural effusion. Radiography is unreliable in establishing or refuting a diagnosis of pericardial effusion. (See the image below.)
Echocardiography : Echocardiography is the imaging modality of choice for the diagnosis of pericardial effusion, as the test can be performed rapidly and in unstable patients. Most importantly, the contribution of...
Please join StudyMode to read the full document