BULL-NECK
bull-neck
Swelling of the neck caused by severely
swollen
lymph glands
,
often related to
infections in the tonsils and throat. (See
also
diphtheria.
)
bullous pemphigoid
An alternative term for
pemphigoid
,
a
skin disease in w hich large, tense blis-
ters develop.
bumetanide
A powerful, short-acting loop
diuretic
drug
used to treat
oedema
(accumula-
tion of fluid in tissues) resulting from
heart failure
,
nephrotic syndrome
(damage
to the kidney’s filtering units), or
cirrho-
sis
.
It may be given by injection for the
emergency treatment of
pulmonary oed-
ema
(fluid in the lungs). Side effects
may include rash and muscle pain.
bundle
Also known as a fascicle, a cluster of
nerve or muscle fibres.
bundle branch block
See
heart block
.
bunion
A thickened pad of tissue or a fluid-
filled bursa (sac) overlying a deformed
big-toe joint. The underlying cause is
HOW BUNIONS FORM
A bunion results from the rubbing of
a shoe against an abnormal outward
projection of the joint at the base of
the big toe (a hallux valgus), leading
to irritation and inflammation. The
joint abnormality is often due to
wearing narrow, pointed shoes with
high heels, although it can also
result from an inherited weakness
in the joint.
Bunion
Valgus deformity of the joint between the first
metatarsal bone and the adjoining phalanx.
an abnormal outward projection of the
big toe called a
halluxvalgus
.
Small buni-
ons can usually be remedied by wearing
well-fitting shoes and a special toe pad
to straighten the big toe. Large bunions
may require surgery to realign the joint
and relieve the pressure.
buphthalmos
A large, prominent eyeball in an infant
due to congenital
glaucoma
(increased
pressure inside the eyeball). The condi-
tion is
usually treated w ith surgery
to reduce the pressure; otherwise, the
child’s sight is progressively damaged.
bupivacaine
A
long-acting
local
anaesthetic
(see
anaesthesia, local
) often used as a
nerve
block
during
childbirth
and in
epidural
anaesthesia
and
spinal anaesthesia
.
Side
effects are uncommon, but high doses
may cause blood pressure to fall.
bupropion
Another name for
amfebutamone
, a drug
used as an aid to stopping smoking.
Burkitt’s lymphoma
A cancer of lymph tissues (see
lymphatic
system
)
characterized by tumours within
the jaw and/or the abdomen. The con-
dition almost exclusively affects children
living in the low-lying, moist, tropical
regions of Africa and New Guinea.
Anti-
cancer drugs
or
radiotherapy
give a partial
or complete cure in about
80
per cent
of cases. (See also
lymphoma
. )
burns
Tissue damage caused by contact with
heat, electricity, chemicals, or radiation.
Burns are classified, according to the
severity of skin damage, as first-, sec-
ond-, or third-degree
(or superficial,
partial thickness, or full thickness).
FIRST-DEGREE BURNS
A first-degree burn causes reddening of
the skin and affects only the epidermis,
(topmost layer of skin). These type of
burns usually heal quickly, but the dam-
aged skin may peel away after a day or
two.
Sunburn
is a common example of a
first-degree burn.
SECOND-DEGREE BURNS
A second-degree burn extends into,
and damages, the dermis (deep layer of
skin), sometimes causing the formation
of blisters. Because some of the dermis
is left to recover, these type of burns
usually
heal
without
leaving
scars,
unless they are very deep.
THIRD-DEGREE BURNS
A third-degree burn destroys the full
skin thickness and may extend to the
muscle
layer
beneath
the
skin. The
affected area w ill look white or charred;
if the burn is very deep, muscles and
bones may be exposed. Even if very
localized, third-degree burns w ill need
specialist treatment and possibly skin
grafts to prevent scarring.
ELECTRICAL BURNS
Electrical burns can cause extensive tis-
sue damage with minimal external skin
damage. The electric current may cause
heart damage.
EFFECTS AND COMPLICATIONS
Extensive first-degree burns
(such as
sunburn) cause pain, restlessness, fever,
and headache, but are not life-threaten-
ing. A second- or third-degree burn that
affects more than ten per cent of the
body surface causes
shock
,
with lowered
blood pressure and a rapid pulse, due to
massive fluid loss from the burned area.
Shock may be fatal if this fluid is not
replaced intravenously.
W hen the skin is burned it can no
longer
protect
the
body
from
con-
tamination by airborne bacteria. The
infection of extensive burns may cause
fatal complications if effective treatment
with
antibiotic drugs
is not available.
Victims who have inhaled smoke may
develop inflammation of the lungs and
may need specialist care for burns of the
eyes and respiratory passages.
TREATMENT
A burn is covered with a non-stick
dressing to keep the area moist.
Anal-
gesic drugs
are given if necessary and
antibiotics are prescribed if there is any
infection. For extensive second-degree
burns, w hich may be slow to heal or
carry a high risk of infection, a topical
antibacterial agent, such as silver sul-
phadiazine, is used. Third-degree burns
always require
skin grafts
,
w hich are
used early to m inimize scarring. Exten-
sive burns may require
plastic surgery
.
burping
Another term for
belching
.
burr hole
A hole made in the skull by a special
drill with a rounded tip (burr). The hole
relieves pressure on the brain that often
results from bleeding inside the skull,
usually due to a
head injury
.
Burr holes
may be part of a
craniotomy
(in w hich a
section of skull is removed for access to
the brain) and may be life-saving.
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