hi let's talk about pelvic autonomics  
hi let's talk about pelvic autonomics  

in this video we'll discuss the basics of the  autonomic supply to the pelvis so as you may  
in this video we'll discuss the basics of the  autonomic supply to the pelvis so as you may  

recall the the pelvic viscera are autonomically  supplied by the inferior hypogastric plexus  
recall the the pelvic viscera are autonomically  supplied by the inferior hypogastric plexus  

which is a mixed autonomic plexus we can see the  inferior hypogastric plexus here has a mesh work  
which is a mixed autonomic plexus we can see the  inferior hypogastric plexus here has a mesh work  

of fibers that are highlighted green to represent  both sympathetic and parasympathetic fibers  
of fibers that are highlighted green to represent  both sympathetic and parasympathetic fibers  

it's important to realize that that mesh work of  fibers is going to extend over the viscera of the  
it's important to realize that that mesh work of  fibers is going to extend over the viscera of the  

pelvis as well so there's going to be a vesicle  plexus associated with the bladder a uterovaginal
pelvis as well so there's going to be a vesicle  plexus associated with the bladder a uterovaginal

plexus associated with the uterus and vagina a  rectal or middle rectal plexus associated with  
plexus associated with the uterus and vagina a  rectal or middle rectal plexus associated with  

the rectum and also a prostatic plexus associated  with the prostate now let's take a look at some  
the rectum and also a prostatic plexus associated  with the prostate now let's take a look at some  

of the inputs for the inferior hypogastric  plexus or communications for the plexus  
of the inputs for the inferior hypogastric  plexus or communications for the plexus  

there are a couple of different sources let's  let's keep the hypogastric nerves in our mind they  
there are a couple of different sources let's  let's keep the hypogastric nerves in our mind they  

are cut here but what these are are condensations  of both sympathetic and parasympathetic fibers  
are cut here but what these are are condensations  of both sympathetic and parasympathetic fibers  

that are entering and leaving the pelvis and  they communicate the superior hypogastric plexus  
that are entering and leaving the pelvis and  they communicate the superior hypogastric plexus  

and the inferior hypogastric plexus so  those hypogastric nerves really talk  
and the inferior hypogastric plexus so  those hypogastric nerves really talk  

between those two plexuses  both in and out of the pelvis  
between those two plexuses  both in and out of the pelvis  

now specifically within the pelvis there are going  to be branches from ventral primary rami of s2  
now specifically within the pelvis there are going  to be branches from ventral primary rami of s2  

3 and 4. we can see the the vprs  here are in yellow so there is s1  
3 and 4. we can see the the vprs  here are in yellow so there is s1  

s2 s3 and s4 and coming off of s2 here we see this  very nice blue branch that is a pelvic splanchnic  
s2 s3 and s4 and coming off of s2 here we see this  very nice blue branch that is a pelvic splanchnic  

nerve coming off of s4 here we can see this blue  branch which kind of runs by s3 and heads down to  
nerve coming off of s4 here we can see this blue  branch which kind of runs by s3 and heads down to  

the inferior hypogastric plexus these are the  pelvic splanchnic nerves and i remember that  
the inferior hypogastric plexus these are the  pelvic splanchnic nerves and i remember that  

pelvic splanchnics are parasympathetics some  of these fibers of the pelvic splanchnic nerves  
pelvic splanchnics are parasympathetics some  of these fibers of the pelvic splanchnic nerves  

can travel to the hindgut either  through the superior hypogastric  
can travel to the hindgut either  through the superior hypogastric  

plexus so by means of those hypogastric  nerves or they can independently travel  
plexus so by means of those hypogastric  nerves or they can independently travel  

up to the hindgut independently of those  hypogastric nerves in terms of the sympathetic  
up to the hindgut independently of those  hypogastric nerves in terms of the sympathetic  

inputs we need to look at the sacral sympathetic  trunk which is highlighted in orange here  
inputs we need to look at the sacral sympathetic  trunk which is highlighted in orange here  

there are various ganglia of the trunk  so there we can see the ganglion of one  
there are various ganglia of the trunk  so there we can see the ganglion of one  

and two and a slight one of three there  and typically it's branches from the first  
and two and a slight one of three there  and typically it's branches from the first  

two ganglia here that are the sacral splanchnics but we actually have branches from s2 and s3 and  
two ganglia here that are the sacral splanchnics but we actually have branches from s2 and s3 and  

these are examples of sacral splanchnic nerves and  i remember that as sacral splanchnic is sympathetic  
these are examples of sacral splanchnic nerves and  i remember that as sacral splanchnic is sympathetic  

so inputs hypogastric nerves mixed pelvic  splanchnics parasympathetics sacral splenics  
so inputs hypogastric nerves mixed pelvic  splanchnics parasympathetics sacral splenics  

sympathetics in terms of the targets of  these this plexus we'll have a vesicle plexus  
sympathetics in terms of the targets of  these this plexus we'll have a vesicle plexus  

serving the urinary bladder a  prostatic plexus which would serve  
serving the urinary bladder a  prostatic plexus which would serve  

if it were present here a prostate gland  and it is not present here a uterovaginal  
if it were present here a prostate gland  and it is not present here a uterovaginal  

plexus serving the uterus and vagina and a rectal  plexus serving the rectum and anal canal in terms  
plexus serving the uterus and vagina and a rectal  plexus serving the rectum and anal canal in terms  

of the functions of this autonomic regulation  they're rather straightforward so in terms of  
of the functions of this autonomic regulation  they're rather straightforward so in terms of  

parasympathetic stimuli we'll have contraction of  the smooth muscle of the bladder and the rectum  
parasympathetic stimuli we'll have contraction of  the smooth muscle of the bladder and the rectum  

um parasympathetics generally are vasodilators so  the vasodilation as a result of parasympathetic  
um parasympathetics generally are vasodilators so  the vasodilation as a result of parasympathetic  

stimulation leads to tumescence so that's the  engorgement of the erectile tissues and that  
stimulation leads to tumescence so that's the  engorgement of the erectile tissues and that  

can further lead to erection there's also the  initiation of glandular secretions so these are  
can further lead to erection there's also the  initiation of glandular secretions so these are  

stimulatory of glands as well the sympathetic  responses so the uh the fight-or-flight response  
stimulatory of glands as well the sympathetic  responses so the uh the fight-or-flight response  

visa constriction that's that's a very common  sympathetic response the inhibition of rectal  
visa constriction that's that's a very common  sympathetic response the inhibition of rectal  

or anal smooth muscle contraction um as well  as the inhibition of bladder muscle contraction  
or anal smooth muscle contraction um as well  as the inhibition of bladder muscle contraction  

um the initiation of emission so this  is going to stimulate the secretion  
um the initiation of emission so this  is going to stimulate the secretion  

of fluid from seminal vesicles  into the urethra it's also going to  
of fluid from seminal vesicles  into the urethra it's also going to  

be stimulatory of the smooth muscle of  the uterus and genital organs helping  
be stimulatory of the smooth muscle of  the uterus and genital organs helping  

to uh to produce ejaculation this is done  in conjunction with somatomotor innervation  
to uh to produce ejaculation this is done  in conjunction with somatomotor innervation  

e.g from the pudendal nerve so sympathetics  and somatic motor help to stimulate ejaculation
e.g from the pudendal nerve so sympathetics  and somatic motor help to stimulate ejaculation

in terms of the general visceral afferent  fibers recall there are two general types and  
in terms of the general visceral afferent  fibers recall there are two general types and  

up until this point our discussions have been  uh fairly straightforward so those gva fibers  
up until this point our discussions have been  uh fairly straightforward so those gva fibers  

that travel along with the parasympathetic fibers  are are typically serving autonomic reflexes and  
that travel along with the parasympathetic fibers  are are typically serving autonomic reflexes and  

the general visceral efferent fibers that  
the general visceral efferent fibers that  

travel with the sympathetics are serving visceral  pain so this isn't the same thing as somatic pain  
travel with the sympathetics are serving visceral  pain so this isn't the same thing as somatic pain  

this is sensing uh distension uh stretching  uh tearing um it's very poorly localized  
this is sensing uh distension uh stretching  uh tearing um it's very poorly localized  

um and generally referred to um to certain regions  now there's something called the uh the pelvic  
um and generally referred to um to certain regions  now there's something called the uh the pelvic  

pain line and the uh the pelvic pain  line corresponds with the inferior  
pain line and the uh the pelvic pain  line corresponds with the inferior  

margin of the peritoneum and so anything above the  pelvic pain line general visceral afferent fibers
margin of the peritoneum and so anything above the  pelvic pain line general visceral afferent fibers

travel with sympathetics anything below the pelvic  pain line those general visceral afferent fibers  
travel with sympathetics anything below the pelvic  pain line those general visceral afferent fibers  

travel with the parasympathetic fibers so that's  that's something new for us um and referred pain  
travel with the parasympathetic fibers so that's  that's something new for us um and referred pain  

from visceral organs can refer to a variety of  places but um generally um that referred pain is  
from visceral organs can refer to a variety of  places but um generally um that referred pain is  

more suprapubic in nature again but still very  poorly localized so we've discussed the uh the  
more suprapubic in nature again but still very  poorly localized so we've discussed the uh the  

autonomics of the the pelvis and the various  inputs to the inferior hypogastric plexus as  
autonomics of the the pelvis and the various  inputs to the inferior hypogastric plexus as  

well as the various autonomic plexus targets of  that inferior hypogastric plexus as well as the  
well as the various autonomic plexus targets of  that inferior hypogastric plexus as well as the  

the general visceral afferent fibers pathways  this is your summary slide thank you for your
the general visceral afferent fibers pathways  this is your summary slide thank you for your