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DictionarySeecastEncyclopediaSeeCastblood cell casts
cast (kast) [ME. casten, to carry] 1. In dentistry, a positive copy of jaw tissues over which denture bases may be made. 2. To make an accurate metallic reproduction of a wax pattern of a dental appliance, tooth crown, or inlay cavity preparation.3. Pliable or fibrous material shed in various pathological conditions; the product of effusion. It is molded to the shape of the part in which it has been accumulated. Casts are classified as bronchial, intestinal, nasal, esophageal, renal, tracheal, urethral, and vaginal; constituents are classified as bloody, fatty, fibrinous, granular, hyaline, mucous, and waxy. DECORATED CAST 4. A solid mold of a part, usually applied in situ for immobilization of fractures, dislocations, and other severe injuries. It is carefully applied to the immobilized part and allowed to dry and harden (over 24 to 48 hr). Care is taken not to apply any pressure to the cast until after the cast is dried and hardened. Synthetic materials, such as fiberglass, are also used, esp. for non–weight-bearing parts of the body. See: illustrationPatient careNeurovascular status distal to the cast is monitored; and any deterioration in circulation and in sensory or motor abilities, such as paresthesias, paralysis, diminished pulses, pallor, coldness, or pain, is documented and reported. Pain or burning under the cast other than a transient sense of warmth (which is expected), is also documented and reported. The cast may be bivalved or removed to relieve pressure on the swollen tissues beneath it. To limit swelling the casted extremity should be supported above heart level for the first 24 hours. All casts must be kept dry to avoid maceration of the skin. Objects should not be placed inside a cast to relieve itching, but relief often can be obtained by applying cold (a well-sealed ice bag) to the cast over the area that itches, or by scratching the opposite extremity in the same area. Joints above and below the cast should be exercised to prevent stiffness and contractures. The patient is instructed in symptoms to be reported, cast care and ways to protect the cast from damage; prescribed exercises or activity limitations; and use of any assistive devices such as slings, crutches, or walker. blood cell castsRed blood cell cast.body castA cast used to immobilize the spine. It may extend from the thorax to the pelvis. bronchial castMucus formed into the shape of the bronchi in which it was previously lodged.broomstick castA type of cast used following skin traction for (Legg-Calvé-Perthes disease. A bar is used between upper femoral casts to maintain abduction. See: Legg-Calvé-Perthes disease EPITHELIAL CAST: (Orig. mag. ×400)epithelial castTubular epithelial cells in the urine, a finding in some cases of glomerulonephritis. illustration FATTY CAST: (Orig. mag. ×400)fatty castA urinary cast, consisting of a mass of fatty globules, seen in the examination of patients with nephrosis. illustrationfibrinous castA yellow-brown cast sometimes seen in glomerulonephritis. granular castA coarse or fine granule, short and plump, sometimes yellowish, similar to a hyaline cast, and soluble in acetic acid. It is seen in inflammatory and degenerative nephropathies. See: cast HYALINE CAST: (Orig. mag. ×400)hyaline castThe most common form of cast found in the urine, transparent, pale, and having homogeneous rounded ends. It may be a benign finding, or may be present in fevers, stress, kidney disease, or unchecked hypertension. illustrationlight castA cast used in orthopedics, made of a lightweight material that is usually applied and then hardened by treating with the heat from a light.Minerva castA body cast that extends from the top of the head to the iliac crests, leaving the facial features exposed, but supporting the chin and neck. It is used to treat odontoid fractures in children. muddy brown castThe presence of cola- or fecal-colored casts in a urine specimen. It is a characteristic finding in acute tubular necrosis of the kidneys. plaster castRigid dressing made of gauze impregnated with plaster of Paris, used to immobilize an injured part, esp. in bone fractures. RED BLOOD CELL CAST: (Orig. mag. ×400)red blood cell castA urinary cast composed principally of red blood cells strongly suggestive of glomerulonephritis. Synonym: blood cell castillustrationspica hip castA cast containing the lower torso and extending to one or both lower extremities. If only one lower extremity is included, it is called a single hip spica; if two are included, it is called a double hip spica. These are used for treating pelvic and femoral fractures. urinary castA cylindrical clump of cells and proteins found in the urine in a wide variety of diseases and conditions. uterine castTissue or mucus from the endometrium passed in exfoliative endometritis or membranous dysmenorrhea. walking castA cast or boot that allows the patient to be ambulatory. Synonym: walking boot See: Walking bootwaxy castA light yellowish, well-defined urinary cast probably made up of disintegrating kidney cells, found in some chronic kidney diseases, glomerulonephritis, and uncontrolled hypertension. WHITE BLOOD CELL CAST: (Orig. mag. ×400)white blood cell castA leukocyte cast found in urine in acute pyelonephritis, interstitial nephritis, and at times, glomerulonephritis. illustrationillustrationillustration |