PERSISTENT VEGETATIVE STATE
turned upside down. In the stomach,
similar muscle movements help to m ix
food with gastric juices and move the
partly digested food into the duodenum
(the first part of the small intestine).
The muscles of the small intestine move
in
a
slow,
back-and-forth
churning
motion that allows more time for the
intestine to absorb nutrients. In the
large intestine, peristaltic contractions
occur only about once every
3
0
m in-
utes. Two or three times a day, however,
usually following a meal, a strong, sus-
tained wave of peristalsis in the colon
forces the contents into the rectum, and
may prompt the urge to defaecate. (See
also the illustrated box.)
p e rito n e a l d ia ly s is
See
d ia ly s is
.
p e rito n e u m
The two-layered membrane that forms a
lining in the abdominal cavity and cov-
ers and supports the abdominal organs.
The peritoneum contains blood vessels,
lymph vessels, and nerves. The surface
area of the peritoneum is equal to that
of the entire skin.
The peritoneum produces a lubrica-
ting fluid that allows the abdominal
organs to glide smoothly over each other.
It also protects the organs against infec-
tion. In addition, the membrane absorbs
fluid and acts as a natural filtering sys-
tem; this function is utilized in one form
of
d ia ly s is
.
The peritoneum may become
inflamed as a complication of an ab-
dominal disorder (see
p e rito n itis
) .
p e rito n itis
Inflammation of the
p e rit o n e u m
(the
membrane lining the abdominal wall
and covering the abdominal organs).
Peritonitis is a serious condition.
CAUSES
The inflammation is almost always due to
irritation and bacterial infection caused by
another abdominal disorder. The most
common cause is
p e rfo ra tio n
of the stom-
ach or intestine wall, which allows bac-
teria and digestive juices to move into the
abdominal cavity. Perforation is usually
the result of a
p e p t ic u lc e r
,
a p p e n d ic itis
(acute inflammation of the appendix), or
d iv e rtic u litis
(inflammation of abnormal
pouches in the wall of the intestine).
Peritonitis may
also
be
associated
with acute
s a lp in g it is
(inflammation of
a fallopian tube),
c h o le c y s titis
(inflam-
mation of the gallbladder), or
s e p t i-
c a e m ia
(blood poisoning).
SYMPTOMS
There is usually severe abdominal pain
over part or all of the abdomen. After
a few hours, the abdomen feels hard,
and
p e r is t a ls is
(wavelike contractions of
the intestinal muscles) stops (see
ile u s ,
p a ra ly t ic
) .
Other symptoms are fever,
bloating, nausea, and vomiting.
D e h y d ra -
tio n
and
s h o c k
may occur.
DIAGNOSIS AND TREATMENT
Diagnosis is made from a
p h y s ic a l e x a m i-
n a t io n
.
The affected person w ill need to
be admitted to hospital without delay.
Surgery may be necessary to deal with
the cause. If the cause is unknown, a
la p a ro s c o p y
or an exploratory
la p a ro to m y
may be performed.
A n t ib io t ic d ru g s
are
often given to destroy bacteria, and
in tra -
v e n o u s in f u s io n s
of fluid may be given to
treat dehydration.
OUTLOOK
In most cases, a full recovery is made.
Rarely, however, intestinal obstruction,
caused by
a d h e s io n s
(bands of scar tis-
sue between loops of intestine), may
occur at a later stage.
p e rit o n s illa r a b s c e s s
An abscess (collection of pus) in the
soft tissue around the tonsils that occurs
as a complication of
t o n s illit is
.
A peri-
tonsillar abscess, also known as quinsy,
causes pain, swallowing difficulties, and
jaw stiffness. The tonsils appear asym-
metrical.
A n t ib io t ic d ru g s
and
a n a lg e s ic
d r u g s
(painkillers) are usually given to
help relieve the symptoms, and, in some
cases, a small surgical incision may be
made to drain the abscess.
p e rm a n e n t te e th
The second set of
t e e th
,
w hich usually
start to replace the primary teeth at
about the age of six. There are
3
2
per-
manent teeth:
16
in each jaw. Each set
of
16
consists of four incisors, two
canines, four premolars and six molars.
(See also
e ru p tio n o f t e e th
. )
p e rm e th rin
A drug included in preparations used
to treat
lic e
and scabies.
p e rn ic io u s a n a e m ia
A type of
a n a e m ia
(reduced blood levels
of the oxygen-carrying pigment
h a e m o -
g lo b in
)
caused by the stomach lining
failing to produce intrinsic factor -
necessary for vitamin B12 absorption.
Deficiency of vitamin B12 prevents bone
marrow from producing normal red
blood cells (see
a n a e m ia , m e g a lo b la s t ic
) .
p e rn io
An alternative term for
c h ilb la in
.
p e ro n e a l m u s c u la r a tro p h y
A rare, inherited disorder characterized
by muscle wasting in the feet and calves
and then in the hands and forearms.
The condition, which is also known as
Charcot-Marie-Tooth disease, is caused
by
degeneration
of some
peripheral
nerves. It usually appears in late child-
hood or adolescence.
Muscle wasting stops halfway up the
arms and legs, making them look like
inverted bottles; sensation may be lost.
There is no treatment for the disorder,
but it is rare for the sufferer to become
totally incapacitated because the disease
usually progresses at a very slow rate.
Life expectancy is normal.
p e rp h e n a z in e
A
p h e n o t h ia z in e
-type
a n tip s y c h o t ic d ru g
that is used to relieve symptoms in psy-
chiatric disorders, such as
s c h iz o p h r e n ia
;
to sedate agitated or anxious patients;
and sometimes for the relief of severe
nausea and vomiting.
Possible adverse effects include ab-
normal movements
of the face
and
limbs, drowsiness, blurred vision, stuffy
nose, and headache. Long-term use of
the drug may cause the movement dis-
order
p a r k in s o n is m
.
P e rs a n tin
A brand name for
d ip y rid a m o le
,
an
a n ti-
p la te le t d r u g
.
Persantin prevents abnormal
b lo o d c lo t tin g
by inhibiting the activity
of platelets (tiny blood cells that aid
clotting). The drug is used to prevent
recurrence of a
s tro k e
or
tra n s ie n t is c h -
a e m ic a tta ck
or
to
prevent the
dev-
elopment of blood clots in people with
prosthetic
h e a rt v a lv e s
.
p e rs is te n t v e g e ta tiv e s ta te
A term used to describe a type of indef-
inite, deep
c o m a
(unconsciousness and
unresponsiveness to stimuli). The con-
dition is caused by damage to areas of
the brain that control higher mental
functions. Although the eyes may open
and close and there may be random
movements of the head and limbs, there
is no response to stimuli such as pain.
Only basic functions, such as breathing
and heartbeat, are maintained due to
functioning of the
b ra in s t e m
. T h e r e
is no
treatment to reverse the situation; with
good nursing care, survival for several
years is possible.
P
601
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