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(hăl″ō-fĭl′ĭk) [″ + philein, to love] Concerning or having an affinity for salt or any halogen.


(hăl′ō-thān) A fluorinated hydrocarbon used as a general anesthetic.

halo vest

(hā′lō″) A device used to immobilize the head and cervical spine following vertebral injury or surgery. It is designed to provide in-line traction of the cervical spine while allowing for a moderate amount of functional independence. The halo vest consists of three parts: (1) the halo, secured into the skull through the use of four pins or screws; (2) the vest, worn over the shoulders and trunk to support the weight of the halo, skull, and cervical spine; and (3) four metal bars connecting the halo to the vest.

PATIENT CARE: The screws attaching the halo to the skull must be kept clean to reduce the risk of infection. Hygiene consists of cleaning each pin two to three times a day as prescribed by a physician. The patient should be instructed on how to use a mirror to inspect the sites for signs of infection, e.g., redness of the skin, or purulent drainage from around the pins. If the vest becomes wet, it should be dried with a hairdryer set on its lowest temperature setting. The shoulders and thorax should be inspected for signs of irritation from the vest. Additional padding may be required around pressure-sensitive areas.

image Complications reported with the halo vest include: (1) incomplete cervical fracture healing (in about 10% to 15% of patients); (2) impairments in balance, vision, and some activities of daily living; (3) infection; (4) loosening of pins; and (5) scarring of skin at pin insertion sites.

SYN: halo vest orthosis.

Halsted, William Stewart

(hal′sted″) U.S. surgeon, 1852–1922.

H. forceps A small curved or straight hemostatic forceps.

H. operation 1. An operation for inguinal hernia. 2. A radical mastectomy for breast.

H. suture An interrupted suture for intestinal or cutaneous wounds.


(hăm-ăr-tō′mă) [Gr. hamartia, defect, + oma, tumor] A tumor resulting from new growth of normal tissues. The cells grow spontaneously, reach maturity, and then do not reproduce. Thus, the growth is self-limiting and benign.

multiple h. A congenital malformation that presents a slowly growing mass of abnormal tissue in multiple sites. The tissues are appropriate to the organ in which the hamartomas are located but are not normally organized. They may appear in blood vessels as hemangiomata, and in the lung and kidney. They are not malignant but cause symptoms because of the space they occupy.


(ham′ăt, hā′māt″) [L. hamatus, hooked] 1. Hooked; unciform. SYN: hamular...

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