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APC4 Flashcards

1
Q

Difference between jejunum and ileum?

A

Wall of jejunum is thicker and more vascular (not obvious in fixed tissue) than that of the ileum

Jejunum has more folds on the luminal surface (PLICAE CIRCULARES) - virtually absent in distal ileum - causes jejunum to feel bulkier

PEYER’S PATCHES of non-encapsulated gut associated lymphoid tissue - present in large numbers in the ileum, few in the jejunum (quite apparent in living tissue but not in fixed tissue)

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2
Q

How do jejunum and ileum appear in radiography? (barium meal)

A

-

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3
Q

What is the small intestine?

A

Extends from the pyloric orifice of the stomach to the iliocaecal junction - consists of duodenum, jejunum and ileum

Jejunum commences at duodenojejunal junction (flexure): point where retroperitoneal duodenum obtains a mesentery and becomes intraperitoneal - situated just below/left of attachment of transverse mesocolon to the PAW

Jejunum and ileum suspended from PAW by a mesentery - lie in the more central and lower parts of the abdominopelvic cavity, surrounded by ascending, descending, transverse and descending parts of colon

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4
Q

What is the duodenojejunal flexure?

A

Jejunum commences at duodenojejunal junction (flexure): point where retroperitoneal duodenum obtains a mesentery and becomes intraperitoneal

Situated just below/left of attachment of transverse mesocolon to the PAW

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5
Q

What is the junction between the jejunum and ileum?

A

Not distinct - gradual change in structure from beginning of jejunum to end of ileum

Gross differences most clearly apparent at each end therefore possible to distinguish proximal jejunum from distal ileum

Sure way is to look at jejunum or ileum when studying small intestine in situ - follow it proximally or distally to one of its fixed points

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6
Q

Peritoneum of the jejunum and ileum?

A

Both invested by visceral peritoneum - reflected onto PAW via MESENTERY of SMALL INTESTINE

ROOT of mesentery is only about 15cm in length but fans out to accommodate whole length of small intestine

Root lies OBLIQUELY across PAW along a line from left of L2 VERTEBRAE to RIGHT SACROILIAC JOINT

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7
Q

What is the blood supply to the jejunum and ileum?

A

Branches of SUPERIOR MESENTERIC which pass via MESENTERY of small intestine and gain access to intestinal wall at the mesenteric border (point where peritoneum diverges to pass around intestine)

Vessels are arranged in ‘ARCADE’ which provide an ANASTOMOTIC supply to the small intestine

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8
Q

What is the superior mesenteric artery (its branches)?

A

Arises abdominal aorta just below celiac at lower border of L1

Main branches of superior mesenteric are:
INFERIOR PANCREATICODUODENAL, 
JEJUNAL
ILEAL
ILEOCOLIC
RIGHT COLIC
MIDDLE COLIC

Jejunal and ileal branches leave left side of superior mesenteric, whereas branches to more distal structures leave its right side

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9
Q

What is the inferior pancreaticoduodenal artery?

A

First branch of superior mesenteric

Anastomses with superior pancreaticoduodenal artery

Both supply the duodenum and pancreas

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10
Q

What are the jejunal/ileal arteries?

A

12-15 jejunal and ileal branches - form characteristic ARCADES (anastomoses) which are relatively fewer in the jejunum than in the ileum (jejuneal and ileal vasa recta are straight arteries coming off the arcades)

Terminal branches (vasa recta) are longer (and fewer) in jejunum than in ileum (more branches in ileum, which are shorter)

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11
Q

What is the ileocolic artery?

A

Passes to RIGHT ILIAC FOSSA to supply TERIMAL ILEUM and ASCENDING COLON

Also arising from ileocolic artery - branches supplying CAECUM and APPENDIX

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12
Q

What are the right and middle colic arteries?

A

Right colic –> ascending colon

Middle colic –> transverse colon

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13
Q

Consequences of obstruction:

1) proximal part of superior mesenteric artery?
2) one of the ileal arcades?
3) one of the terminal branches to intestinal wall?

A

1) ?
2) ?
3) ?

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14
Q

What is the venous drainage of the jejunum and ileum?

A

Tributaries of SUPERIOR MESENTERIC VEIN (accompany the branches of SUPERIOR MESENTERIC artery)

UNITES with SPLENIC vein behind the NECK of the pancreas to form HEPATIC PORTAL vein

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15
Q

What is the lymphatic drainage of the jejunum and ileum?

A

First line of defence = Peyer’s patches (gut associated lymphoid tissue) - structure similar to lymph nodes but without connective tissue capsule

  • PPs situated in lamina propria and submucosa, and drain the local areas, sending efferents to proximal lymph nodes
  • In region of the TERMINAL ILEUM, gut associated lymphoid tissue is most numerous and visible

Gut wall –> three groups of nodes:

  • First: MESENTERY near WALL of intestine
  • Second: among arterial ARCADES within MESENTERY
  • Third: around ORIGIN of SUPERIOR MESENTERIC - drains via INTESTINAL LYMPH TRUNK to CISTERNA CHYLI
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16
Q

What is the enteric nervous system?

A

Autonomous system controlling peristaltic and secretory activities of gut - similar level of complexity as spinal cord (especially number of neurons)

INTRAMURAL nerve plexus includes SUBMUCOUS and MYENTERIC plexuses

Extrinsic autonomic fibres from sympathetic and parasympathetic system modulate activities of the ENS and hence gut itself

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17
Q

What is the sympathetic innervation of the small intestine?

A

Derived T9 and T10 segments - via THORACIC SPLANCHNIC nerves

Preganglionic fibres synapse in the CELIAC or SUPERIOR MESENTERIC GANGLIA

Postganglionic fibres pass to viscera via PLEXUSES around BRANCHES of the SUPERIOR MESENTERIC artery

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18
Q

What is the parasympathetic innervation of the small intestine?

A

Preganglionic from VAGUS, distributed with BRANCHES of SUPERIOR MESENTERIC artery to the viscera - pass into SUBMUCOUS and MYENTERIC plexuses and relay in GANGLIA in the gut wall

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19
Q

What is the afferent nerve supply of the small intestine?

A

Visceral afferents leave gut wall - relay info to CNS

Some travel in VAGUS nerve and may be concerned with REFLEX activity

PAIN impulses are conveyed along SYMPATHETIC

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20
Q

Which parts of the large intestine have a mesentery?

A

?

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21
Q

All of exercise 3

A
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22
Q

What is the large intestine?

A

Begins ileocaecal junction in right iliac fossa and includes caecum (associated appendix), ascending colon, transverse colon, descending colon, sigmoid colon (which is continuous with rectum)

  • Wall has INNER CIRCULAR and OUTER LONGITDUINAL layer of smooth muscle: longitudinal layer condensed into 3 bands called TENIAE COLI (teniae coli of caecum merge at appendix)
  • Covered in fatty tags - APPENDICES EPIPLOICAE - deposits of fat between the colonic wall and the visceral peritoneum
  • Wall has puckered appearance - SACCULATIONS or HAUSTRATIONS
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23
Q

How does ileocaecal junction appear histologically?

A

Abrupt change of appearance

Mucosa changes as ileum need vili/microvili for nutrient absorption (this is mostly proximal ileum but also distal)

Caecum has more MUCIN cells (mucus secretion)

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24
Q

What is the ileocaecal valve?

A

Regulates passage of material from ileum to caecum and prevents reflux of caecal contents into ileum

Projects a papilla in life (in cadaver valve consists of two semilunar shaped flaps which project into lumen of caecum)

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25
Q

What is the vermiform appendix?

A

Narrow worm-like tube which arises from the posteromedial wall of the caecum

Commonly lies behind or alongside caecum but may extend into pelvis

Sometimes lies posterior or anterior to terminal ileum where it in contact with PAW/AAW

Connected to owed part of MESENTERY of ILEUM by a short MESOAPPENDIX which contains the vessels and nerves supplying appendix

Teniae coli of caecum merge at appendix

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26
Q

Blood supply of appendix?

A

Appendicular artery - terminal branch of ileocolic artery

Appendicular vessels lie close to the viscus in the mesoappendix

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27
Q

What is the caecum?

A

Right iliac fossa - blind ended sac, continuous superiorly with ascending colon

Ileum opens into medial wall of caecum at ILEOCAECAL JUNCTION

Covered on LATERAL and ANTERIOR surfaces by PERITONEUM, and sometimes suspended by a mesentery

Teniae coli easily recognisable on caecum, converging at base of vermiform appendix (locating teniae coli can help locate base of appendix and vice versa)

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28
Q

Why is appendicitis pain initially felt in the umbilical region, later localising to right iliac region?

A

Starts off as referred visceral sensation

More advanced - point tenderness following sufficient luminal distention - somatic pain

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29
Q

How does appendix appear on histology?

A

Differences from large intestine:

Outer layer of fibres in the muscularis externa forms a continuous layer

Lymphoid tissue in mucosa and submucosa - there are often follicles containing paler germinal centres similar to the follicles of Peyers patches in the small intestine

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30
Q

What is the ascending colon?

A

Continuous with caecum and occupies right iliac, right lumbar and right hypochondriac regions

At visceral surface of liver - colon bends anteriorly and to left where it is continuous with the transverse colon (right colic / hepatic flexure)

Does not normally have a mesentery - posterior surface is in direct contact with the FASCIA of the MUSCLES of the PAW - therefore relatively fixed in position

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31
Q

What is the transverse colon?

A

Loops across umbilical region to the left hypochondriac region where it is continuous with the descending colon at the left colic (splenic) flexure

Upright posture - sometimes descends into pelvis

Left colic flexure is slightly higher than the right

Suspended from the PAW by the TRANSVERSE MESOCOLON which allows considerable mobility and results in variability in position depending on the contents and physique/posture of individual

32
Q

What is the descending colon?

A

Begins in left hypochondriac region at left colic flexure - which is suspended from the undersurface of the diaphragm by the phrenocolic ligament (double layer of peritoneum)

Occupies left hypochondriac, left lumbar and left iliac regions

33
Q

What is the paracolic gutter?

A

Space between the colon and abdominal wall (left and right paracolic gutters)

RIGHT paracolic gutter continuous superiorly with the HEPATORENAL POUCH and the ADITUS to the lesser sac, inferiorly with the RECTOVESICAL / RECTOUTERINE pouch

34
Q

What are the infracolic spaces?

A

Space between colon and mesentery of small intestine = infracolic space (left and right infracolic spaces)

35
Q

Clinical significance of parabolic gutters, infracolic spaces of peritoneal cavity?

A

?

36
Q

What is the sigmoid colon?

A

Continues as the sigmoid colon in the LEFT ILIAC region and is identified by presence of a MESENTERY

Sigmoid colon takes the form of a loop of variable length, in some individuals projects superiorly in abdominal cavity

Initially descends in contact with LEFT PELVIC WALL and then crosses pelvic cavity between rectum and bladder(male)/uterus(female)

Finally arches back to reach midline at level of S3 where it is continuous with the rectum

37
Q

What is the sigmoid mesocolon?

A

V shaped
Suspends viscus from the pelvic wall

Apex of attachment at bifurcation of the LEFT COMMON ILIAC artery, overlies the LEFT URETER

38
Q

Where in colon would you find anatomoses between branches of the superior and inferior mesenteric arteries?

A

?

39
Q

Blood supply of large intestine?

A

Superior and inferior mesenteric (mid and hindgut origin)
Branches of superior and inferior form anastomsis which lies along MESENTERIC border of colon in form of a MARGINAL ARTERY

40
Q

What is the inferior mesenteric artery?

A

Ventral branch of abdominal aorta arising at about L3

Branches:

LEFT COLIC
SIGMOID
SUPERIOR RECTAL

41
Q

What is the left colic artery?

A

Gives rise to ascending and descending branch

Ascending branch anastomoses with MIDDLE COLIC artery (from superior mesenteric)

Descending branch anastomoses with the two or three SIGMOID arteries

42
Q

What is the superior rectal artery?

A

Terminal branch of inferior mesenteric

Supplies rectum

43
Q

What is the venous drainage of the large intestine?

A

Drainage closely corresponds to arterial supply - except for termination of main veins

SUPERIOR MESENTERIC vein joins the SPLENIC vein to form the HEPATIC PORTAL vein

INFERIOR M vein receives tributaries corresponding to branches of inferior m. artery, joins the SPLENIC vein (sometimes variation can occur - IM vein drains directly into SM vein)

ASCENDING and DESCENDING colon are RETROPERITONEAL and lie in contact with structures on the PAW - therefore some PORTAL VENOUS blood drains to the IVC by SMALL ANASTOMOTIC veins on PAW

44
Q

What is the superior mesenteric vein?

A

Crosses the 3rd (horizontal) part of the duodenum and passes behind the NECK of the pancreas where it joins the SPLENIC vein to form the HEPATIC PORTAL vein

45
Q

What is the inferior mesenteric vein?

A

INFERIOR M vein receives tributaries corresponding to branches of inferior m. artery and passes behind the BODY of the pancreas to join the SPLENIC vein (sometimes variation can occur - IM vein drains directly into SM vein)

46
Q

What is the lymphatic drainage of the large intestine?

A

Similar to that of small intestine

Areas of gut associated lymphoid tissue in the wall - not Peyer’s patches (only present in small intestine)

Lymph subsequently drains via lymph nodes to INTESTINAL LYMPH TRUNK and then to CISTERNA CHYLI (just below diaphragm)

Nodes in three groups:

1) Close to intestinal wall
2) Along branches of main arteries supplying large intestine
3) Continuous with PRE-AORTIC nodes whose efferents drain into INTESTINAL TRUNK

47
Q

What is the parasympathetic supply of the large intestine?

A

VAGUS as far as PROXIMAL 2/3 of transverse colon
Vagal fibres pass through CELIAC and SUPERIOR MESENTERIC plexuses WITHOUT synapsing
- SYNPASE in WALL of intestine in SUBMUCOSAL and MYENTERIC plexuses

Distal 3rd onwards - from PELVIC SPLANCHNIC nerves (synapse in wall of gut in same way)

48
Q

What is the sympathetic supply of the large intestine?

A

Arises mainly from T11 to L2 and PREGANGLIONIC fibres SYNAPSE in SUPERIOR and INFERIOR MESENTERIC GANGLIA

Up to proximal 2/3rds transverse colon, POSTGANGLIONIC fibres from SUPERIOR MESENTERIC ganglion

From distal 3rd of transverse colon onwards, received via POSTGANGLIONIC fibres from the INFERIOR MESENTERIC GANGLION

49
Q

What is the afferent supply of the large intestine?

A

Runs with the vagus - probably concerned with reflex activities

Pain transmitted in afferent fibres travelling with sympathetic nerves

50
Q

What is the rectosigmoid junction?

A

S3

Tenia coli of colon spread out to become the OUTER LONGITUDINAL SMOOTH MUSCLE layer of the RECTUM

Termination of the OMENTAL APPENDICES associated with the colon

51
Q

Course of the rectum?

A

Follows curve of sacrum, forming SACRAL FLEXURE of rectum

As the rectum passes anteroinferiorly, pass the tip of the coccyx, it turns 80 DEGREES posteroinferiorly to PIERCE PELVIC FLOOR MUSCULATURE (anorectal/perineal flexure)

52
Q

What is the anorectal junction?

A

Anorectal or perineal flexure

Where rectum pierces pelvic floor musculature

53
Q

What is puborectalis?

A

One of the muscles of the pelvic floor

Band of muscle embedded in pelvic floor which originates from BODY of PUBIS and forms U-shaped sling around ANORECTAL FLEXURE

Makes angle more acute between rectum and anus
Role in continence and defecation (relaxation increases the angle between rectum and anus allowing defecation along with relaxation of internal and external anal sphincters)

54
Q

What are the rectal folds? Function?*

A

Three traverse folds projecting from rectal wall into lumen (variable, but commonly 3)

Each fold often corresponds to an indentation on the rectal exterior, which are related to coronal flexures of the rectum

Function of the folds?

55
Q

What is the lower part of the rectum?

A

Usually dilated and known as ampulla

56
Q

What is the peritoneum of the rectum?

A

Sigmoid colon intraperitoneal - fully enclosed by peritoneum

Rectum - begins to be reflected off the gut tube and onto pelvic walls and other viscera located in pelvic cavity

Superior third: covers ANT and LAT surfaces only
Middle third: covers ANT surface
Inferior third: no coverings, now SUBPERITONEAL

No peritoneum on posterior aspect as this is contact with the sacrum

57
Q

What are the relationships of the rectum?

A

Pelvic floor supports rectum

Inferior part of PREVERTEBRAL autonomic plexus lies on each side

Lateral = coils of small intestine

Posterior = lower three segments of sacrum & coccyx - rectum loosely attached by fascia to the front of the sacrum

Between bone and rectum = muscles of pelvic walls, and lower three sacral and coccygeal nerves, pelvic splanchnic nerves and the sympathetic chains

Superior rectal artery accompanied by corresponding vein lies posterior to upper end of rectum before dividing into its branches

58
Q

Male relations of rectum?

A

Anteriorly and below peritoneum related to base of bladder, seminal vesicles, prostate, terminal parts of ductus deferens and the ureters

Superior 2/3rds related to base of bladder

Coils of small intestine lie in rectovesical pouch

59
Q

Female relations of rectum?

A

Anteriorly and below peritoneum, related to vagina

Superior 2/3rds of rectum related to vagina and uterus

Coils of small intestine lie in rectouterine pouch

60
Q

What is the anal canal?

A

Begins at level of pelvic diaphragm, ends at anus

Lumen is closed except during the passage of faeces or flatus

Lower part has 6-10 longitudinal mucosal folds - ANAL COLUMNS - contain blood vessels from SUPERIOR RECTAL arteries and veins

At lower ends columns joined by small crescentic folds of mucous membrane - ANAL VALVES - above each = small recess (anal SINUS)

61
Q

What are the anal sinuses?

A

Small recesses above the anal valves

May retain fecal matter and become infected, valves may be torn by hard faeces

62
Q

What are the anal valves?

A

Anal columns joined by small crescentic folds of mucous membrane
May be torn by hard faeces

Situated along pectinate line

Junction between endoderm and ectoderm (anal membrane in embryo) may be at this point, or anywhere in the region which extends 15mm below the anal valves (TRANSITIONAL zone or PECTEN)

63
Q

What is the transitional zone of the anal canal?

A

Lined by non-keratinised stratified epithelium

Becomes continuous with the skin lining the lowest part of the anal canal

64
Q

What are the sphincters of the anal canal?

A

Internal: consist of CIRCULAR smooth muscle and continuous with inner circular muscle layer of rectum - autonomic innervation, sympathetics cause contraction/closure, parasympathetic = relaxation/opening

External: surrounds lower 2/3rds anal canal - consists of striated muscle muscle (pelvic floor contributes on either side) supplies by INFERIOR RECTAL BRANCH (motor and sensory) of PUDENDAL nerve and PERINEAL branch of FOURTH SACRAL NERVE

External divided into: DEEP, SUPERFICIAL, SUBCUTANEOUS - fibres blend together. SC lies immediately deep to skin surrounding anus, DEEP blends with pelvic FLOOR muscle - attached to ANORECTAL junction. INTERSPHINCTERIC GROOVE between LOWER part of INTERNAL anal sphincter and SC part of EXTERNAL anal sphincter

65
Q

How to identify vessels and nerves of rectum / anal canal?

A

Pelvic floor useful landmark

Above: going onto walls of rectum = SUPERIOR RECTAL ARTERY (branch of IM), SUPERIOR RECTAL VEIN –> IMV –> portal vein

Along pelvic floor (small) = MIDDLE RECTAL ARTERY (branch of INT ILIAC)

Below pelvic floor INFERIOR RECTAL ARTERY (from INT ILIAC, crosses ISCHIOANAL FOSSA to get to anal canal)

66
Q

What is risky about surgery of ischioanal fossa?

A

Damage to nerves and vessels of rectum/anus - INFERIOR RECTAL NERVE from pudendal - motor and sensory - external anal sphincter

Ischioanal fossa underneath pelvic floor (from behind), with ischium laterally - sits between ischium and anal canal - obturator internus forms lateral wall, lined by obturator fascia usually full of fat (and fibrous tissues)

but if take fat away can see vessels/nerves –> INFERIOR RECTAL ARTERY & INFERIOR RECTAL NERVE

Obturator fascia contains the PUDENDAL canal - houses INTERNAL PUDENDAL VESSELS (from INT ILIAC) and PUDENDAL nerve (from sacral plexus)

67
Q

What is the blood supply of the rectum / anal canal?

A

INFERIOR MESENTERIC artery (artery of embryonic c hindgut) supplies RECTUM and UPPER part of ANAL CANAL

LOWER part of ANAL canal supplied by branch of INT ILIAC

Rectal arteries form poor anastomoses with eachother

68
Q

What is the superior rectal artery?

A

Terminal branch of INFERIOR MESENTERIC artery that descends into pelvis in ROOT of SIGMOID MESOCOLON, superior to levator ani

On reaching rectum divides into two branches descending either side of rectum - terminal branches of these vessels pierce the muscle layer to enter the submucosa and descend into the ANAL COLUMNS as far as the anal VALVES - form LOOPED ANASTOMOSES

69
Q

What are the middle rectal arteries?

A

Branches of INTERNAL ILIAC, pass along pelvic floor, superior to levator ani, and provide additional supply to MUSCLE of the LOWER part of the RECTUM and UPPER part of the ANAL canal

70
Q

What are the inferior rectal arteries?

A

Branches of INTERNAL PUDENDAL arteries, cross ischioanal fossa to supply ANAL canal BELOW level of ANAL VALVES, anal SPHINCTERS and SKIN around anus

Form poor anastomoses with eachother

71
Q

Venous drainage of rectum and anal canal?

A

Extensive plexuses with no valves - consist of INTERNAL part DEEP to the rectal and anal EPITHELIUM, EXTERNAL part SUPERFICIAL to the MUSCLE layer

INTERNAL RECTAL plexus drains RECTUM and UPPER half of ANAL CANAL –> SUPERIOR RECTAL vein –> INF MES

EXTERNAL plexus drained by ALL 3 vessels (SUPERIOR, MIDDLE, INFERIOR rectal veins), therefore some blood drains to INFERIOR MESENTERIC vein to PORTAL system and some drains to INTERNAL ILIAC vein –> IVC

Connections between two plexuses - anatomoses between superior and inferior rectal veins example of PORTO-SYSTEMIC anastomoses

External plexus present around rectum and anal canal communicates with plexuses around PELVIC VISCERA, and also INTERNAL VERTEBRAL venous plexus

72
Q

Lymphatic drainage of rectum and anal canal?

A

3 routes according to arterial supply

UPPER part of RECTUM -> nodes related to wall of rectum (PARARECTAL) then nodes associated with SUPERIOR RECTAL artery to PRE-AORTIC lymph nodes around origin of INFERIOR MESENTERIC and then to CISTERNA CHYLI

From ANORECTAL region, lymph passes in vessels accompanying the MIDDLE RECTAL VESSELS to the INTERNAL ILIAC lymph nodes

Anal canal BELOW ANAL VALVES - flows to medial group of SUPERFICIAL INGUINAL lymph nodes - which also receive lymph from the rest of the perineum –> COMMON ILIAC –> PARA-AORTIC –> CISTERNA CHYLI

73
Q

Nerve supply of rectum and anal canal?

A

Lining derived from endoderm (autonomic + visceral afferents)

Preganglionic SYMP fibres (T11-L2) synapse in INFERIOR MESENTERIC GANGLION, postganglionic fibres pass onwards via SUPERIOR and PAIRED INFERIOR HYPOGASTRIC PLEXUSES

PARASYMP preganglionic efferent from S2-4, pass in PELVIC SPLANCHNIC nerves to INFERIOR HYPOGASTRIC PLEXUSES, SYNAPSE in WALL of rectum and anal canal, above level of anal valves

Sympathetic fibres inhibit musculature & glands of rectum/upper anal canal, stimulate contraction of INTERNAL anal sphincter - opposite by parasympathetic

Visceral afferent (PAIN) travel with both SYM and PARASYM fibres whilst REFLEX activity mediated by PARASYM

Anal canal derived from PROCTODEUM supplied by somatic nerves - INFERIOR RECTAL branch of PUDENDAL nerve (S2,S3) and PERINEAL BRANCH of 4th SACRAL nerve supply LOWER ANAL canal and musculature of EXTERNAL ANAL SPHINCTER

74
Q

Difference between internal and external haemorrhoids? *

A

Internal = rectum - can’t see or feel them, don’t usually hurt as few pain sensing nerves there - sometimes prolapse or enlarge and protrude outside of anal sphincter - prolapse may be seen or hurt as pain sensing nerves in anus - usually go back into rectum

External = anus - of move or prolapse can see/feel it- clots sometimes form

75
Q

How does an ischioanal abscess occur?

During drainage, what nerves/vessels vulnerable to damage?

A

Infection at one of the ANAL SINUSES - four types: perianal, ischiorectal, intersphincteric, and supralevator - causes pain in perineum (may get constipation, drainage from rectum, fever/chills)

Drainage: pudendal nerve, pudendal artery –> internal pudendal artery

If pudendal nerve completely severed - incontinence, loss of sensation *

GI (12 decks)

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