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halo effect, expert halo effect

The tendency of novices to trust that individuals with specialized training or expertise will always make the best choices.


(hal′ŏ-jĕn) [Gr. hals, salt + -gen] Any of the elements (chlorine, bromine, iodine, fluorine, and astatine) forming Group 7 (VII) of the periodic table. These elements have very similar chemical properties, combining with hydrogen to form acids and with metals to form salts.


(hă″lō-pĕr′ĭ-dŏl) A neuroleptic drug used to treat patients with psychotic illnesses, extreme agitation, or Tourette’s syndrome.


(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...

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