(kast )

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.
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: illus.

   Patient Care: Neurovascular 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. A simple means of doing this is to place a plastic bag over the cast before showering and attach it to the skin with duct tape, then enclose that in a second larger bag and tape that to the skin over the first. 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, care of the cast, 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.

   SEE: Nursing Diagnoses Appendix.

blood cell c.Red blood cell cast.

body c.A cast used to immobilize the spine. It may extend from the thorax to the pelvis.

bronchial c.Mucus formed into the shape of the bronchi in which it was previously lodged.

epithelial c.Tubular epithelial cells in the urine, a finding in some cases of glomerulonephritis.

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fatty c.A urinary cast, consisting of a mass of fatty globules, seen in the examination of patients with nephrosis.

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fibrinous c.A yellow-brown cast sometimes seen in glomerulonephritis.

granular c.A 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.

hyaline c.The 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.

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light c.A 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 c.A 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.

plaster c.Rigid dressing made of gauze impregnated with plaster of Paris, used to immobilize an injured part, esp. in bone fractures.

red blood cell c.A urinary cast composed principally of red blood cells strongly suggestive of glomerulonephritis. SYN: blood cell cast.

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total contact c.A walking cast applied to the plantar surface of the foot to distribute pressure and permit healing of foot ulcers (as in diabetes mellitus or other forms of neuropathy).

The cast is molded to the contour of the foot and extends its full length, from the heel through the arch, over the metatarsals and the toes. It must be applied carefully to avoid slippage or friction.

urinary c.A cylindrical clump of cells and proteins found in the urine in a wide variety of diseases and conditions.

uterine c.Tissue or mucus from the endometrium passed in exfoliative endometritis or membranous dysmenorrhea.

walking c.A cast or boot that allows the patient to be ambulatory. SYN: walking boot.

SEE: Walking boot

See video

waxy c.A 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 c.A leukocyte cast found in urine in acute pyelonephritis, interstitial nephritis, and , at times, glomerulonephritis.

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