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Pericardiocentesis is the aspiration of fluid from the pericardial space that surrounds the heart. This procedure can be life saving in patients with cardiac tamponade, even when it complicates acute type A aortic dissection and when cardiothoracic surgery is not available. [1] Cardiac tamponade is a time sensitive, life-threatening condition that requires prompt diagnosis and management. Historically, the diagnosis of cardiac tamponade has been based on clinical findings. Claude Beck, a cardiovascular surgeon, described 2 triads of clinical findings that he found associated with acute and chronic cardiac tamponade. The first of these triads consisted of hypotension, an increased venous pressure, and a quiet heart. It has come to be recognized as Beck's triad, a collection of findings most commonly produced by acute intrapericardial hemorrhage. Subsequent studies have shown that these classic findings are observed in only a minority of patients with cardiac tamponade. [2] The detection of pericardial fluid has been facilitated by the development and continued improvement of echocardiography. [3] Cardiac ultrasound is now accepted as the criterion standard imaging modality for the assessment of pericardial effusions and the dynamic findings consistent with cardiac tamponade. With echocardiography, the location of the effusion can be identified, the size can be estimated (small, medium, or large), and the hemodynamic effects can be examined by assessing for abnormal septal motion, right atrial or right ventricular inversion, and decreased respiratory variation of the diameter of the inferior vena cava.
The menstrual cycle is the regular natural change that occurs in the female reproductive system like the uterus and ovaries that make pregnancy possible. The cycle is required for the production of ovocytes, and for the preparation of the uterus for pregnancy.
Pregnancy occurs when an egg is fertilized by a sperm, grows inside a woman's uterus (womb), and develops into a baby. In humans, this process takes about 264 days from the date of fertilization of the egg, but the obstetrician will date the pregnancy from the first day of the last menstrual period (280 days 40 weeks).
The pituitary gland is often portrayed as the "master gland" of the body. Such praise is justified in the sense that the anterior and posterior pituitary secrete a battery of hormones that collectively influence all cells and affect virtually all physiologic processes. The pituitary gland may be king, but the power behind the throne is clearly the hypothalamus. As alluded to in the last section, some of the neurons within the hypothalamus - neurosecretory neurons - secrete hormones that strictly control secretion of hormones from the anterior pituitary. The hypothalamic hormones are referred to as releasing hormones and inhibiting hormones, reflecting their influence on anterior pituitary hormones.
There are 3 major parts of the respiratory system: the airway, the lungs, and the muscles of respiration. The airway, which includes the nose, mouth, pharynx, larynx, trachea, bronchi, and bronchioles, carries air between the lungs and the body's exterior.