IN VITRO FERTILIZATION (IVF)
p i p e ) . E n d o t r a c h e a l i n t u b a t i o n i s c a r r i e d
o u t i f m e c h a n i c a l
v e n t i l a t i o n
i s n e e d e d
t o d e l i v e r o x y g e n i n t o t h e l u n g s .
T h e a n a e s t h e t i s t l o o k s d o w n t h e p a t i -
e n t ’s t h r o a t w i t h a l a r y n g o s c o p e ( v i e w i n g
i n s t r u m e n t )
t o i d e n t i f y t h e v o c a l c o r d s .
T h e
t u b e
i s
t h e n
p a s s e d
t h r o u g h
t h e
m o u t h
o r
n o s e
a n d
d o w n
t h e
t h r o a t
b e t w e e n t h e v o c a l c o r d s a n d t r a c h e a .
T h e t e r m “ i n t u b a t i o n ” i s a l s o u s e d t o
r e f e r t o t h e p l a c e m e n t o f a
g a s t r i c
o r
i n t e s t i n a l t u b e i n t h e s t o m a c h f o r p u r -
p o s e s
o f
s u c t i o n
o r
t h e
g i v i n g
o f
n u t r i e n t s ( s e e
f e e d i n g , a r t i f i c i a l
).
in tu s s u s c e p tio n
A c o n d i t i o n i n w h i c h p a r t o f t h e i n t e s -
t i n e t e l e s c o p e s i n o n i t s e l f , f o r m
i n g
a
t u b e
w i t h i n
a
t u b e ,
u s u a l l y
r e s u l t i n g
i n i n t e s t i n a l o b s t r u c t i o n
( s e e
i n t e s t i n e ,
o b s t r u c t i o n
o f
).
T h e
c o n d i t i o n
u s u a l l y
a f f e c t s t h e l a 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 , w h e r e i t j o i n s t h e l a r g e i n t e s t i n e .
CAUSES
I n
s o m e
c a s e s
t h e r e
i s
a n
a s s o c i a t i o n
w i t h a r e c e n t i n f e c t i o n . I n o t h e r c a s e s , i t
m a y s t a r t a t t h e s i t e o f a
p o l y p
o r
M e c k -
e l ’s d i v e r t i c u l u m
( a p o u c h - l i k e p r o j e c t i o n
f r o m t h e i l e u m
) .
SYMPTOMS AND COMPLICATIONS
I n t u s s u s c e p t i o n o c c u r s m
o s t c o m
m
o n -
l y i n c h i l d r e n u n d e r t h e a g e o f t w o . A n
a f f e c t e d
c h i l d u s u a l l y
d e v e l o p s
s e v e r e
a b d o m i n a l c o l i c ; v o m i t i n g i s c o m
m o n ,
a n d b l o o d a n d m u c u s a r e o f t e n f o u n d
i n t h e f a e c e s .
I n s e v e r e
c a s e s o f i n t u s s e p t i o n ,
t h e
b l o o d s u p p l y t o t h e i n t e s t i n e b e c o m e s
b l o c k e d .
G a n g r e n e
( t i s s u e
d e a t h ) ,
f o l -
l o w e d b y
p e r i t o n i t i s
( i n f l a m
m
a t i o n
o f
t h e
a b d o m i n a l
l i n i n g )
o r
p e r f o r a t i o n
( r u p t u r e ) , m a y r e s u l t .
Intussusception
This disorder is characterized by part of the intestine
telescoping in on itself. The problem usually occurs
at the junction between the ileum and the caecum.
TREATMENT
I n s o m e c a s e s , a n
e n e m a
c a n b e u s e d t o
f o r c e
t h e
a b n o r m a l
a r e a
o f
i n t e s t i n e
b a c k
i n t o
a
n o r m a l p o s i t i o n .
I n
o t h e r
c a s e s , s u r g e r y m a y b e n e c e s s a r y t o r e p o -
s i t i o n t h e i n t e s t i n e .
in v a s iv e
A t e r m u s e d t o d e s c r i b e a n y t h i n g t h a t
f o r c i b l y e n t e r s o r s p r e a d s t h r o u g h t h e
b o d y . T h e
w o r d
“ i n v a s i v e ”
i s
u s u a l l y
a p p l i e d t o c a n c e r o u s t u m o u r s o r h a r m
-
f u l m i c r o o r g a n i s m
s t h a t t e n d t o s p r e a d
t h r o u g h o u t b o d y t i s s u e s . I t c a n a l s o b e
u s e d t o r e f e r t o s u r g e r y . I n a n “ i n v a -
s i v e ”
m
e d i c a l
p r o c e d u r e ,
t h e
b o d y
t i s s u e s a r e p e n e t r a t e d b y a n i n s t r u m e n t
d u r i n g s u r g e r y . ( S e e a l s o
m i n i m a l l y i n v a -
s i v e s u r g e r y
;
n o n i n v a s i v e
. )
in v e rte d n ip p le
A n i n d r a w i n g o f t h e
n i p p l e
.
T h e c o n d i -
t i o n c a n b e l o n g s t a n d i n g o r m a y d e v e l o p
i n l a t e r l i f e a s a r e s u l t o f c h a n g e s i n t h e
b r e a s t t i s s u e . P o s s i b l e c a u s e s i n c l u d e n o r -
m a l c h a n g e s a s s o c i a t e d w i t h a g i n g o r , i n
s o m e c a s e s , a n u n d e r l y i n g c a n c e r .
in v itro
T h e p e r f o r m a n c e o f b i o l o g i c a l p r o c e s s e s
i n
a l a b o r a t o r y r a t h e r t h a n w i t h i n t h e
b o d y T h e t e r m l i t e r a l l y m e a n s “ i n g l a s s ” .
in v itro fe rtiliz a tio n (IVF)
A t e c h n i q u e u s e d t o t r e a t
i n f e r t i l i t y
w h e n
i t s c a u s e c a n n o t b e d e t e r m i n e d o r t r e a t -
e d o r i f t h e r e i s a b l o c k a g e i n a f a l l o p i a n
t u b e . I V F i s a l s o u s e d t o t r e a t c o u p l e s
a f f e c t e d b y a
g e n e t i c d i s o r d e r
b e c a u s e t h e
PROCEDURE FOR IN VITRO FERTILIZATION
Fertilization of eggs outside a woman’s body can be performed to treat some types
ofinfertility. One such technique used is in vitro fertilization; the main stages
involved in this procedure are illustrated below.
Days 16 to 17
About two days later, the eggs are examined
to see iftheyhave been fertilized and have
started to develop into embryos. Ifthey have,
two or three ofthe best embryos are
introduced into the woman’s uterus through
the vagina. Further embryos may be frozen
and stored.
Days 14 to 15
Immediately before ovulation (which may be
induced with drugs), ripe eggs are removed by
laparoscopy (above) or by ultrasound-guided
needle aspiration through the vagina or the
abdomen. The eggs are mixed with the man’s
sperm in a dish (above, centre), which is then
put in an incubator.
I
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