STOCKINETTE
S
s to c k in e tte
A s o f t , e l a s t i c a t e d f a b r i c u s e d f o r i t e m s
s u c h a s b a n d a g e s .
S t o k e s -A d a m s a tta c k s
R e c u r r e n t e p i s o d e s o f t e m p o r a r y l o s s o f
c o n s c i o u s n e s s d u e t o i n s u f f i c i e n t b l o o d
f l o w
f r o m
t h e
h e a r t
t o
t h e
b r a i n .
S t o k e s - A d a m s a t t a c k s a r e c a u s e d b y a n
i r r e g u l a r h e a r t b e a t
( s e e
a rrh y th m ia , c a r -
d ia c ) ,
w h i c h
p r e v e n t s
t h e
h e a r t
f r o m
p u m p i n g p r o p e r l y , o r b y c o m p l e t e
h e a rt
b lo c k ,
w h i c h
c a u s e s
t h e
h e a r t
t o
s t o p
b r i e f l y . M o s t a f f e c t e d p e o p l e a r e f i t t e d
w i t h a
p a c e m a k e r
t o p r e v e n t a t t a c k s .
s to m a
A t e r m w i t h t h e l i t e r a l m e a n i n g m o u t h
o r o r i f i c e . A c o m
m
o n u s e o f t h e t e r m i s
t o d e s c r i b e t h e s t o m a t h a t c a n b e c r e a t -
e d s u r g i c a l l y i n t h e a b d o m i n a l w a l l ( s e e
c o lo s to m y ; ile o s to m y )
t o a l l o w t h e i n t e s -
t i n e t o e m p t y i n t o a b a g o r p o u c h o n
t h e s u r f a c e o f t h e s k i n .
s to m a c h
A h o l l o w , b a g l i k e o r g a n o f t h e
d ig e s tiv e
s y s t e m
l o c a t e d i n
t h e
l e f t
s i d e
o f t h e
a b d o m e n
u n d e r t h e
d i a p h r a g m . A t i t s
u p p e r e n d , t h e s t o m a c h i s c o n n e c t e d t o
t h e
o e s o p h a g u s
( g u l l e t ) ,
a n d
a t
t h e
l o w e r
e n d i t j o i n s
t h e
d u o d e n u m
( t h e
f i r s t p a r t o f t h e s m a l l i n t e s t i n e ) .
STRUCTURE
T h e s t o m a c h i s f l e x i b l e a n d i n t h e a v e r -
a g e a d u l t c a n e x p a n d t o h o l d a r o u n d 1 . 5
l i t r e s o f f o o d . I t s w a l l c o n s i s t s o f l a y e r s o f
l o n g i t u d i n a l a n d
c i r c u l a r
m u s c l e ,
l i n e d
b y s p e c i a l g l a n d u l a r c e l l s t h a t s e c r e t e g a s -
t r i c j u i c e , a n d s u p p l i e d b y b l o o d v e s s e l s
a n d n e r v e s . A s t r o n g m u s c l e a t t h e l o w e r
e n d o f t h e s t o m a c h f o r m s a r i n g c a l l e d
t h e p y l o r i c s p h i n c t e r t h a t c a n c l o s e t h e
o u t l e t l e a d i n g t o t h e d u o d e n u m .
DISORDERS OFTHE STOMACH
Disorders of the stomach have a variety
of causes. Because the stomach is a
reservoir, disorders of the emptying
of stomach contents occur. Other
problems relate to the stomach’s role
in the preparation of ingested food
for digestion.
Infection
The large amount of hydrochloric acid
secreted by the stomach protects it from
some infections by destroying many of
the bacteria, viruses, and fungi that are
taken in with food and drink. When the
protective power is insufficient, a variety
of gastrointestinal infections may occur.
Tumours
Stom ach ca n cer
is one of the commonest
forms of cancer. Early symptoms are often
mistaken for
in d ig e s tio n
,
and diagnosis is
often delayed until it is too late for a cure.
Any change in the customary functioning
of the digestive system is important,
especially after the age of
5 0
.A persistent
feeling of fullness, or pain before or after
meals, should never be ignored.
Unexplained loss of appetite or frequent
nausea should always be reported to a
doctor. A tumour in the upper part of
the stomach, near the opening of the
oesophagus, can cause obstruction and
difficulty in swallowing. Sometimes a
stomach tumour remains “silent” and the
first signs are due to the appearance of
secondary growths elsewhere in the body.
Benign (noncancerous)
p o ly p s
can
also develop in the stomach.
Ulceration
The acid and other digestive juices
secreted by the stomach sometimes
attack the stomach lining. The healthy
stomach is prevented from digesting
itself mainly by the protective layer of
mucus secreted by the lining and by the
speed with which damaged surface cells
are replaced by the deeper layers. Many
influences can upset this delicate
balance. One of the most important is
excessive acid secretion. The resulting
p e p tic u lc e rs
are probably the most
common serious stomach disorder.
Peptic ulcers are most often caused by
H
e l i c o b a c t e r p y l o r i
infection, but are
sometimes caused by stress, severe
injury such as major burns, or after
surgery and serious infections; often
they occur for no apparent reason. The
stomach lining can be damaged by
large amounts of aspirin or alcohol,
sometimes causing
g a stritis
(inflammation of the stomach lining.
This may eventually lead to ulceration.
Autoimmune disorders
Pernicious anaemia (see
a n a e m ia ,
p e rn ic io u s
) is caused by the failure of
the stomach lining to produce intrinsic
factor, a substance that facilitates the
absorption of vitamin B^ (necessary
for red blood cell formation). Failure to
produce intrinsic factor occurs if there
is atrophy of the stomach lining, which
also causes failure of acid production.
Tests that determine a person’s ability
to absorb vitamin B^ are important
in the investigation of this condition.
Pernicious anaemia is usually due to
an
a u to im m u n e d is o rd e r
.
Other disorders
Enlargement of the stomach may be
caused when scarring from a chronic
peptic ulcer occurs at the stomach
outlet. It may also be a complication
of
p y lo ric s t e n o s is
,
a rare but serious
condition in which there is narrowing
of the stomach outlet. Rarely, the
stomach may become twisted and
obstructed, a condition called volvulus.
INVESTIGATION
Stomach disorders are investigated
primarily by
barium X-rayexaminations
and/or
gastroscopy.
Occasionally, a
biopsy
(removal of a tissue sample for
microscopic analysis) is performed.
ANATOMY OF THE STOMACH
Food enters the
stomach from the
oesophagus and exits
into the duodenum.
Muscle
Oesophagus
Body of
stomach
Stomach lining
Antrum
Pyloric sphincter
Duodenum
Parts of the stomach
The fundus, the body ofthe stomach, and
the antrum are the three main parts; the
lower oesophageal segment and pyloric
sphincters control entry and exit of food.
The stomach lining
secretes gastric juice
and protective mucus.
Fundus
714
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