By W. Nefarius. West Virginia University Parkersburg. 2018.
In addition to chyle buy coumadin 1mg amex, all the lymph from As shown in Figure 16-4 cheap coumadin 2mg with mastercard, the thoracic duct receives below the diaphragm empties into the cisterna chyli, lymph from all parts of the body except those superior passing through the various clusters of lymph nodes. The first part of the duct The thoracic duct extends upward through the di- is enlarged to form a cistern, or temporary storage aphragm and along the posterior wall of the thorax into THE LYMPHATIC SYSTEM AND LYMPHOID TISSUE ✦ 335 the base of the neck on the left side. Here, it receives the Lymph Nodes left jugular lymphatic vessels from the head and neck, the left subclavian vessels from the left upper extremity, and The lymph nodes, as noted, are designed to filter the other lymphatic vessels from the thorax and its parts. The segments of lymphatic vessels located between the An indented area called the hilum (HI-lum) is the exit valves contract rhythmically, propelling the lymph along. Changes in the medulla, has populations of immune cells, including pressures within the abdominal and thoracic cavities lymphocytes and macrophages (phagocytes) along open caused by breathing aid the movement of lymph during channels that lead into the efferent vessels. The main groups ◗ Lymphoid Tissue include the following: 16 Lymphoid (LIM-foyd) tissue is distributed throughout ◗ Cervical nodes, located in the neck in deep and super- the body and makes up the specialized organs of the lym- ficial groups, drain various parts of the head and neck. These ther- sulting fluid accumulation in the subcutaneous tissues) can apies may include elevation of the affected limb, manual lym- cause another form of edema called lymphedema. The clinical phatic drainage through massage, light exercise, and firm hallmark of lymphedema is chronic swelling of an arm or leg, wrapping of the limb to apply compression. Primary For example, further blockage of lymph drainage can be pre- lymphedema is a rare congenital condition caused by abnor- vented by wearing loose clothing and jewelry, carrying a purse mal development of lymphatic vessels. One of the most com- swelling, other complications include poor wound healing, mon causes of lymphedema is the removal of axillary lymph skin ulcers, and increased risk of infection. Capsule ◗ Inguinal nodes, located in the groin region, receive lymph drainage from Afferent the lower extremities and from the Trabecula lymphatic external genital organs. It is located in the superior left hypochondriac region of the ab- Cortical nodules domen, high up under the dome of with germinal centers the diaphragm, and normally is pro- tected by the lower part of the rib cage (Fig. Surgeons use radioac- In breast cancer, the degree of invasion of nearby lymph tive tracers to identify the first nodes that receive lymph from nodes helps determine what treatments are required after sur- the area of a tumor.
However cheap 5 mg coumadin amex, Although tapering of dose may not facilitate recovery steroid therapy with modest to high doses for 2 weeks of the hypothalamic–pituitary–adrenal axis cheap 5 mg coumadin fast delivery, it may re- or longer will depress hypothalamic and pituitary activ- duce the possibility of adrenal insufﬁciency. This is im- ity and result in a decrease in endogenous adrenal portant, since severe hypotension caused by adrenal in- steroid secretion and eventual adrenal atrophy. Adrenal patients have a limited ability to respond to stress and insufﬁciency should always be considered in patients an enhanced probability that shock will develop. Long- who are being withdrawn from prolonged glucocorti- acting steroids, such as dexamethasone and betametha- coid therapy unless metyrapone or insulin hypo- sone, suppress the hypothalamic–pituitary axis more glycemia tests are performed to exclude this possibility. Thus, osteoporosis can be a sequela of rheuma- virtually every phase and component of the inﬂamma- toid arthritis, and the physician is left to determine tory and immune responses, they have assumed a major whether the untoward effect is iatrogenic or is merely a role in the treatment of a wide spectrum of diseases sign of the disease being treated. Thus, the problems as- tions have proven to be efﬁcacious, particularly in chil- sociated with withdrawal from long-term steroid ther- dren. However, the detrimental effects of glucocorti- apy in rheumatoid arthritis are additional reasons coids on growth are signiﬁcant for children with active steroid treatment should be initiated only after rest, arthritis. Although steroids offer symptomatic relief physiotherapy, and nonsteroidal antiinﬂammatory from this disorder by abolishing the swelling, redness, drugs or after methotrexate, gold, and D-penicillamine pain, and effusions, they do not cure. THERAPEUTIC USES OF STEROID Based on the concept that asthma is an inﬂamma- HORMONES tory disease that leads to airway obstruction, inhaled glucocorticoids are the ﬁrst-line treatment for moderate to severe asthma. Inhaled preparations are particularly Replacement Therapy effective when used to prevent recurrent attacks. Adrenal insufﬁciency may result from hypofunction of This therapy is often combined with an inhaled bron- the adrenal cortex (primary adrenal insufﬁciency, chodilator such as a -adrenergic agonist. A doubling of the may also be used at lower doses in combination with cortisol dose may be required during minor stresses or other drugs for the treatment of vasculitis, lupus infections. Steroids are valuable in the mentation, prednisone can be substituted for cortisol to prevention and treatment of organ transplant rejec- avoid ﬂuid retention. In Guillain- considered, since patients with deﬁcient corticotrophin Barré syndrome glucocorticoids reduce the inﬂamma- secretion generally do not have abnormal function of tory attack and improve ﬁnal outcome, while in chronic the zona glomerulosa. Since cortisol replacement ther- inﬂammatory demyelinating polyneuropathy glucocor- apy is required for life, adequate assessment of patients ticoids suppress the immune reaction but may not re- is critical to avoid the serious long-term consequences tard the progression of the disease.