VASOVAGAL ATTACK
v a s c u lit is
I n f l a m m a t i o n o f b l o o d v e s s e l s . V a s c u l i t i s
u s u a l l y l e a d s t o d a m a g e t o t h e l i n i n g o f
v e s s e l s ,
w i t h
n a r r o w i n g
o r
b l o c k a g e ,
t h a t r e s t r i c t s o r s t o p s b l o o d f l o w . A s a
r e s u l t , t h e b o d y t i s s u e s s u p p l i e d b y t h e
a f f e c t e d v e s s e l s a r e d a m a g e d , o r t h e y a r e
d e s t r o y e d b y
is c h a e m ia .
V a s c u l i t i s i s t h o u g h t t o b e c a u s e d i n
m o s t c a s e s b y t h e p r e s e n c e o f m i n u t e
b o d i e s , c a l l e d i m m u n e c o m p l e x e s , i n t h e
c i r c u l a t i n g
b l o o d .
I m m u n e
c o m p l e x e s
( c o n s i s t i n g
o f
a n tig e n s
b o u n d t o
a n ti-
b o d ie s )
a r e n o r m a l l y d e s t r o y e d b y w h i t e
b l o o d
c e l l s ,
b u t
s o m e t i m e s
a d h e r e
t o
t h e w a l l s o f b l o o d v e s s e l s , w h e r e t h e y
c a u s e i n f l a m m a t i o n . I n s o m e c a s e s , t h e
a n t i g e n s a r e
v iru s e s .
V a s c u l i t i s i s t h e b a s i c d i s e a s e p r o c e s s
t h a t o c c u r s i n a n u m b e r o f d i s o r d e r s .
T h e s e
i n c l u d e
p o ly a rt e rit is n o d o s a , e ry -
th em a n o d o s u m , H e n o c h -S c h o n le in p u rp u ra ,
s e r u m s ic k n e s s ,
t e m p o ra l a rt e rit is ,
a n d
B u e r g e r ’s d is e a s e .
v a s d e fe re n s
E i t h e r
o f a p a i r
o f t u b e s
t h a t
c o n v e y
s p e r m
f r o m
e a c h
te s tis
t o
t h e
u re th ra
( t h e t u b e t h a t c a r r i e s s p e r m a n d u r i n e
t h r o u g h t h e p e n i s t o b e e x p e l l e d ) . T h e
p l u r a l f o r m i s v a s a d e f e r e n t i a .
v a s e c to m y
T h e o p e r a t i o n o f m a l e s t e r i l i z a t i o n . V a s -
e c t o m y i s a m
i n o r s u r g i c a l p r o c e d u r e ,
p e r f o r m e d
u n d e r
a
l o c a l
a n a e s t h e t i c
( s e e
a n a e s t h e s ia , lo c a l),
t h a t c o n s i s t s o f
LOCATION OF THE VAS DEFERENS
The vas deferens passes from the
epididymis, up and around the
bladder, before entering the
prostate, where it connects to a
tube from the seminal vesicle to
form the ejaculatory duct.
Vas
Seminal
HOW VASECTOMY IS PERFORMED
This operation blocks the passage of
sperm from the testes but does not
prevent the prostate and other glands
from secreting the fluids that form most
of the semen. Hence it has little effect
on the volume of the ejaculate and no
effect on orgasm.
Vas deferens
Spermatic cord
Site o f incision
Testis
1
Under a local anaesthetic, incisions
are made on both sides of the scrotum;
the vas deferens is then cut free of the
spermatic cord.
2
A loop of the vas deferens is freed and
brought out through the incision. There are
now several possibilities; usually, a length of
the vas deferens is cut out.
3
In order to prevent the cut ends from
rejoining, they are often bent back and
tightly closed with ligatures. They are then
pushed back into the spermatic cord.
4
The skin incision is now closed with three
or four dissolvable or tape sutures. When
the local anaesthetic wears off, there is usually
a mild, dull, aching pain for a few days.
c u t t i n g o u t a s h o r t l e n g t h o f e a c h
va s
d e fe re n s
( a d u c t t h a t c a r r i e s s p e r m f r o m
a t e s t i s t o t h e u r e t h r a ) . F o r m
o r e d e t a i l
o n h o w t h e p r o c e d u r e i s p e r f o r m e d , s e e
H o w v a s e c to m y is p e rf o r m e d
b o x ,
a b o v e .
A f t e r v a s e c t o m y , t h e m a n c o n t i n u e s t o
a c h i e v e o r g a s m a n d e j a c u l a t e a s n o r m a l ,
b u t t h e
s e m e n
n o l o n g e r c o n t a i n s
s p e r m
,
w h i c h a r e r e a b s o r b e d i n t h e t e s t e s .
M a l e s t e r i l i z a t i o n i s a s a f e a n d e f f e c -
t i v e m e t h o d o f
c o n tra c e p t io n .
R a r e l y , t h e
s e v e r e d e n d s o f a v a s d e f e r e n s r e u n i t e ,
a n d s p e r m
a p p e a r
i n
t h e
e j a c u l a t e .
I f
t h i s o c c u r s , t h e m a n c a n s a f e l y u n d e r g o
a n o t h e r v a s e c t o m y . S o m e o p e r a t i o n s t o
r e s t o r e f e r t i l i t y a f t e r v a s e c t o m y a r e s u c -
c e s s f u l ,
b u t
t h e
p r o c e s s
s h o u l d
b e
r e g a r d e d a s i r r e v e r s i b l e .
v a s o c o n s tric tio n
N a r r o w i n g
o f
b l o o d
v e s s e l s ,
c a u s i n g
r e d u c e d
b l o o d
f l o w
t o
a
p a r t
o f t h e
b o d y . V a s o c o n s t r i c t i o n
u n d e r
t h e
s k i n
o c c u r s
i n
r e s p o n s e
t o
t h e
c o l d
a n d
r e d u c e s h e a t l o s s f r o m t h e b o d y .
v a s o d ila tio n
W
i d e n i n g o f b l o o d v e s s e l s t h a t c a u s e s
i n c r e a s e d b l o o d f l o w t o a p a r t o f t h e
b o d y . V a s o d i l a t i o n u n d e r t h e s k i n o c c u r s
a s a r e s p o n s e t o h o t w e a t h e r , r e s u l t i n g
i n i n c r e a s e d h e a t l o s s f r o m t h e b o d y .
v a s o d ila t o r d ru g s
A g r o u p o f d r u g s t h a t w i d e n t h e b l o o d
v e s s e l s . V a s o d i l a t o r
d r u g s
i n c l u d e
A C E
in h ib it o r d r u g s
,
a lp h a - b lo c k e r d ru g s , c a lc i-
u m c h a n n e l b lo c k e rs ,
a n d
n itra te d ru g s .
S o m e v a s o d i l a t o r s a r e u s e d t o t r e a t d i s -
o r d e r s
i n
w h i c h
a b n o r m a l
n a r r o w i n g
o f
b l o o d
v e s s e l s
r e d u c e s
b l o o d
f l o w
t h r o u g h t h e t i s s u e s , t h e r e b y i m p a i r i n g
t h e
s u p p l y
o f o x y g e n .
S u c h
d i s o r d e r s
i n c l u d e
a n g in a p e c t o r is
a n d
p e r ip h e r a l
v a s c u la r d is e a s e .
V a s o d i l a t o r s
a r e
a l s o
u s e d t o t r e a t
h y p e rt e n s io n
( h i g h b l o o d
p r e s s u r e )
a n d
h e a rt f a ilu re
( r e d u c e d
p u m p i n g e f f i c i e n c y ) . V a s o d i l a t o r d r u g s
m a y
c a u s e
f l u s h i n g ,
h e a d a c h e s ,
d i z z i -
n e s s , f a i n t i n g , a n d s w o l l e n a n k l e s .
v a s o p re s s in
A n o t h e r n a m e f o r
A D H .
v a s o v a g a l a tta c k
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
a s
a
r e s u l t o f s u d d e n s l o w i n g o f t h e h e a r t -
b e a t ,
u s u a l l y
b r o u g h t
o n
b y
s e v e r e
V
783
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