Term
| official definition of chronic constipation |
|
Definition
presence of 2 of the following for at least 3 months, with symptom onset at least 6 months prior to diagnosis
1. straining during >= 25% of defecations
2. lumpy or hard stools in >= 25% of defecations
3. sensation of incomplete evacuation for >=25% of defecations
4. sensation of anorectal obstruction/blockage for >=25% of defecations
5. manual maneuvers to facilitate >= 25% of defecations (ex., digital evacuation, suport of pelvic floor)
6. <3 defecations/week
7. loose stools are rarely present without the use of laxatives |
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Term
| With constipation, a long history of symptoms suggests a ____________ disorder, while the new onset of constipation may suggest a _____________ disease |
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Definition
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|
Term
| What 3 main stests are usueful in evaluation constipation |
|
Definition
colonoscopy
radiography
colonic transit tests |
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|
Term
| Abdominal pain or rectal bleeding suggests primary or secondary constipation? |
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Definition
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Term
| A person complains of constipation, a deepening voice, and feeling cold all the time. What might she have? |
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Definition
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Term
| In a person with constipation, a gaping or asymmetrical anal opening may suggest: |
|
Definition
| neurologic disorder impairing sphincter function |
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|
Term
| Classes of medications most commonly associated with constipation. |
|
Definition
opioids (esp. when used for chronic pain)
diuretics
antidepressants
antihistamines
antispasmodics
anticonvulsants
aluminum-containing acids |
|
|
Term
|
Definition
| an aganglionic section of bowel that starts at the anus and progresses upwards about 30 cm.; leads to functional constipation because there is the absence of the recto-anal inhibitory reflex. |
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Term
| What nervous systems are involved in colonic & anorectal motor functions? |
|
Definition
enteric (visceral motor)
sympathetic
parasympathetic |
|
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Term
| What are some features of primary constipation due to slow colonic transit? |
|
Definition
uncommon
<1 bowel movement/week
lack of urge to defecate
malaise, fatigue
poor response to fiber or laxatives
most commonly occurs in young women |
|
|
Term
| What are some types of primary constipation with normal transit & normal pelvic floor |
|
Definition
Irritable Bowel Syndrome (IBS)
Functional (Idiopathic) constipation |
|
|
Term
| Are men or women more likely to get Functional Constipation? |
|
Definition
|
|
Term
| What are some causes of obstructive secondary constipation? |
|
Definition
colon cancer
extrinsic malignancy
strictures (diverticular or post-ischemic)
anal fissure
anal stenosis
post-surgical abnormalities
megacolon
rectocele |
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|
Term
|
Definition
|
|
Term
|
Definition
| a tear in the rectovaginal septum (a tough, fibrous, sheet-like divider between the rectum and vagina). Rectal tissue bulges through this tear and into the vagina as a hernia. There are two main causes of this tear: childbirth, and hysterectomy. |
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Term
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Definition
| an abnormal dilation of the colon, often accompanied by a paralysis of the peristaltic movements of the bowel. May be caused by Hirschsprung’s disease, medication, chronic inflammation of the colon (toxic megacolon), or Chagas disease. |
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|
Term
| What might you see in a patient that would lead you to suspect a neurogenic origin for their constipation? |
|
Definition
| other neurogenic symptoms |
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|
Term
| What are some types of central neurogenic disorders that can lead to constipation? |
|
Definition
Multiple Sclerosis
Parkinson's
spinal injury or tumor |
|
|
Term
| What are some types of peripheral neurogenic disorders that can lead to constipation? |
|
Definition
Hirschsprung's disease
autonomic neuropathy
Chaga's disease
amyloidosis
slceroderma |
|
|
Term
| What are some metabolic/endocrine causes of chronic constipation? |
|
Definition
pregnancy
diabetes mellitus
hypothyroidism
panhypopituitarism
hypokalemia/hypomagnesemia
hypercalcemia
uremia |
|
|
Term
| Which gender is more likely to get constipation? |
|
Definition
|
|
Term
| What is the difference between primary and secondary constipation? |
|
Definition
Primary constipation- a disordered function of the colon or rectum.
Secondary constipation- includes
mechanical small or large bowel obstructions,
neurogenic and myopathic disorders,
and systemic illnesses. |
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|
Term
| Where and from what does the Superior Mesenteric Artery (SMA) arise? |
|
Definition
| Arises from the anterior surface of the abdominal aorta, just below the celiac trunk |
|
|
Term
| What does the Superior Mesenteric Artery (SMA) supply? |
|
Definition
The intestine, from the lower part of the duodenum through 2/3 of the transverse colon, as well as the pancreas
(so, the parts of the GI are tract it does NOT supply are the upper duodenum and above, and the distal transverse colon, descending colon, sigmoid colon, and rectum) |
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|
Term
| From where does the Superior Mesenteric Vein (SMV) drain blood? |
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Definition
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Term
| Behind the neck of the pancreas, the superior mesenteric vein (SMV) combines with the ___________ vein to form the ______________ vein. |
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Definition
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|
Term
| What does the Inferior Mesenteric Artery supply? |
|
Definition
| Left colic (or splenic) flexure, descending colon, sigmoid colon, and the upper part of the rectum |
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|
Term
| The territory of distribution of the Inferior Mesenteric Artery is more or less equivalent to the embryonic ___________ |
|
Definition
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|
Term
| The inferior mesenteric artery branches off: |
|
Definition
| the anterior surface of the abdominal aorta (a few inches below the celiac trunk) |
|
|
Term
| What are the 5 branches of the superior mesenteric artery? |
|
Definition
inferior pancreaticoduodenal artery
middle colic artery
right colic artery
intestinal arteries
ileocolic artery |
|
|
Term
| The middle colic artery is a branch of the _______________ that mostly supplies the ______________. |
|
Definition
superior mesenteric artery
transverse colon |
|
|
Term
There are 1000X more ________ gut flora than __________ gut flora.
(hint: metabolism) |
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Definition
|
|
Term
| What are 3 vitamins that are mainly produced by gut flora? |
|
Definition
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|
Term
| What is the function of the ileocecal valve? |
|
Definition
| it prevents backflow into the small intestine |
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|
Term
| How does the ileocecal valve work? |
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Definition
| the ileocecal valve protrudes into the lumene of the cecum; jwhen there's pressure in the cecum, it squashes the ileocecal valve closed (this prevents food in the cecum from moving back into the ileum) |
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Term
|
Definition
| muscular, thickened area in last few cm of the ileum, opens & closes to regulate speed of movement of chyme from small intestine to large intestine |
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|
Term
| Is the ileocecal sphincter normally fully open, full closed, or somewhere in between? |
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Definition
| it is normally slightly constricted to slow emptying of the ileum into the cecum |
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|
Term
| What effect does pressure (distention) and chemical irritation in the terminal ileum have on the ileocecal sphincter & peristalsis |
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Definition
| it relaxes (opens) the ileocecal sphincter & excites peristalsis |
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|
Term
| What effect does pressure (distention) and chemical irritation in the cecum have on the ileocecal sphincter & peristalsis? |
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Definition
| it excites (closes) the ileocecal sphincter & inhibits peristalsis |
|
|
Term
What is the difference between the following?
ileocecal valve
ileocecal sphincter |
|
Definition
ileocecal valve--the last bit of the ileum, which protrudes into the lumen of the cecum; it's floppy, so when there's pressue in the cecum is squashes the tube closed
purpose: to keep food from flowing backwards from the cecum to the ileum
ileocecal sphincter--a bit of muscular, thickened wall in the ileum just before it becomes the ileocecal valve
purpose: to control the rate of flow of food into the cecum |
|
|
Term
| What happens to the ileocecal sphincter during appendicitis? |
|
Definition
it spasms shut
no more food can travel from the ileum to the cecum |
|
|
Term
| What 2 nerve types regulate the ileocecal sphincter reflex? |
|
Definition
myenteric plexus in gut wall
autonomic nerves |
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Term
| The proximal colon receives parasympathetic input from the ________ nerve, while the distal colon, rectum, and anus receive parasympathetic input from the ___________ nerves |
|
Definition
|
|
Term
| The proximal colon receives sympathetic input from the ________ ganglion & __________________ ganglion |
|
Definition
ciliary
superior mesenteric |
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Term
| The distal colon receives sympathetic input from the ________ ganglion. |
|
Definition
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|
Term
| The rectum and anal canal receive sympathetic input from the ____________ plexus |
|
Definition
|
|
Term
| The colon receives sympathetic input from what nerve roots? |
|
Definition
|
|
Term
| The external anal sphincter receives voluntary motor innervation from the ____________ nerves. |
|
Definition
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|
Term
| What are the major things the colon absorbs |
|
Definition
water
electrolytes
short chain fatty acids |
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Term
|
Definition
| three separate longitudinal ribbons of smooth muscle on the outside of the ascending, transverse, descending and sigmoid colons |
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Term
|
Definition
| slow (~90 s) contraction of circular and longitudinal muscles (tenia coli) in the large intestine, for the purpose of mixing and rolling feces and allowing water absorption |
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Term
|
Definition
| sac-like bulges in the large intestine; there’s always some haustra because the taeneaa coli (3 longitudinal ribbons of muscle on the colon) is shorter than the large intestine, but which part is haustra & which part is contracted changes, and the unstimulated parts of the intestine bulge even more during haustration |
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|
Term
| ______________ in the colon is similar to segmentation movements in the small intestine |
|
Definition
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|
Term
| Is movement of food in an oral to aboral direction the purpose of haustration? |
|
Definition
| No. Sometimes haustration moves a little bit in an aboral direction, contributing to propulsion of food, but the main purpose of haustration is to mix and roll feces to allow maximum water absorption |
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|
Term
|
Definition
Propulsive movements in the colon that move feces to rectum and stimulate defecation reflex (a modified type of peristalsis)
Usually only occur 1-3 times per day (esp. soon after eating breakfast) |
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|
Term
| Explain the steps of mass movement in the colon. |
|
Definition
First, a constrictive ring forms at a distended or irritated point in the colon (usually the transverse colon)
Then, rapidly, ~20 cm of colon distal to the constrictive ring relaxes, losing their haustra
Then the whole 20 cm contracts together, pushing fecal matter down the colon. The contraction builds for ~30 s, then relaxes for 2-3 minutes
Then, another mass movement occurs, further down the colon
A series of mass movements occurs over 10-30 minutes, then ceases |
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Term
|
Definition
| an increase in colon motility when food stretches the stomach, leading to an urge to poop after a meal |
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Term
| An overactive gastrocolic reflex has been implicated in pathogenesis of ________________________ |
|
Definition
| Irritable Bowel Syndrome (IBS) |
|
|
Term
| About how long does it take food to move from the ileocecal valve to the anus? |
|
Definition
|
|
Term
|
Definition
| a thickening of circular smooth muscle at the end of the rectum; not voluntarily controled |
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|
Term
|
Definition
striated (skeletal) muscle, surrounds internal anal sphincter
voluntary control |
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|
Term
| The crypts of Lieberkühn mainly secrete: |
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Definition
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|
Term
| The crypts of Lieberkühn secrete more alkaline mucin when the receive stimulation from ____________ nerves |
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Definition
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|
Term
| In order to poo, higher brain centers must _____________(inhibit/enhance) pudendal nerve activity |
|
Definition
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|
Term
| Why are anthraquinones such gentle laxatives? |
|
Definition
becuase when given, they are inactivated by being conjugated with glycosides
bacteria in the colon slowly activate by freeing from the glycoside |
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|
Term
| Anthraquinones rely on ___________ to activate them; a process that takes 6-12 hours. |
|
Definition
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|
Term
| How does castor oil work as a laxative? |
|
Definition
| Damage mucosal surface of microvilli so that they leak fluid |
|
|
Term
| Side effects of castor oil |
|
Definition
cause cramping
Chronic use destroys gut mucosa
and decreases absortion area
leading to chronic diarrhea |
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|
Term
| How does liquid petrolatum or mineral oil work as a laxative? |
|
Definition
| coats the inside of the intestine & prevents it from absorbing water |
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|
Term
| What are some possible side effects of using liquid petrolatum or mineral oil as a laxative? |
|
Definition
interferes with absorption of fat-soluble vitamins (KADE), other nutrients, & some drugs
harmful to lungs if aspirated |
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|
Term
| Why does long-term use of opioids cause increasing constipation? |
|
Definition
o Develop tolerance to analgesic effects, but no tolerance to constipating effects
With long-term use, you must increase the dosage of opioids over time. Expect constipation as you increase opioids over terminal illnesses |
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|
Term
| Is castor oil a "fast and furios" or "slow and gentle" laxative? |
|
Definition
|
|
Term
| Are ionic salts (Mg, Na, phosphates) a "fast and furios" or "slow and gentle" laxative? |
|
Definition
|
|
Term
|
Definition
| a tough fibrous layer surrounding the kidney and covered in a thick layer of adipose tissue |
|
|
Term
|
Definition
| muscular tubes that take urine from kidneys to bladder |
|
|
Term
| suprarenal glands (adrenal glands) |
|
Definition
| endocrine glands that sit on top of the kidneys |
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|
Term
| suprarenal glands are aka |
|
Definition
|
|
Term
| What does the quadratus lumborum do? |
|
Definition
| depresses rib 12; flexes trunk laterally |
|
|
Term
| What does the psoas major do? |
|
Definition
|
|
Term
| What does the psoas minor do? |
|
Definition
| helps psoas major in flexing thigh & trunk |
|
|
Term
| What does the iliacus muslce do? |
|
Definition
| flexes thigh (along with psoas major) |
|
|
Term
|
Definition
| the hole in the diaphragm through which the esophagus passes. The esophageal hiatus can act as a second sphincter, above the LES, providing further protection from stomach contents |
|
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Term
|
Definition
| part of the stomach herniates through the esophageal hiatus of the diaphragm into the thoracic cavity |
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|
Term
| central tendon of the diaphragm |
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Definition
| The 2 domes of the diaphragm are connected in the middle by a central tendon, which has no attachments and is incompletely divided into 3 leaves, resembling a wide clover leaf |
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Term
|
Definition
| a ligament under the diaphragm that connect the right & left crura as it arches over the anterior part of the aorta (forms the aortic hiatus) |
|
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Term
|
Definition
| a thickening of the fascia covering the psoas major as it passes through the diaphragm |
|
|
Term
|
Definition
| a ligament under the diaphragm that arches across the upper part of the quadratus lumborum |
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|
Term
| The median artucate ligament is a ligament under the diaphragm that connects the right & left crura as it arches over the anterior part of the aorta. It forms the ____________ hiatus |
|
Definition
|
|
Term
| located near the spleen, in front of the left kidney; the only part of the pancreas that contains Pancreatic Polypeptic (PP) cells) |
|
Definition
|
|
Term
| The ________ of the pancrease is lodged within the curve of the duodenum |
|
Definition
|
|
Term
| Where is the pancrease relative to the aorta? |
|
Definition
| the body of the pancreas is in front of the aorta |
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|
Term
| Where is the pancrease relative to the left kidney? |
|
Definition
| the tail of the pancreas is in front of the left kidney |
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|
Term
| The _____________ duct joins up with the common bile duct to form the ampulla of Vater, which enters the duodenum |
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Definition
|
|
Term
| The pelvic floor consists of the _________ and __________ muscles & their fascial coverings |
|
Definition
|
|
Term
| The pelvic floor is aka the pelvic ___________ |
|
Definition
|
|
Term
| What happens when the pelvic floor contracts? |
|
Definition
raises the entire pelvic floor
flexes the anorectal canal during defectiaon
contributes to the voluntary control of urination
helps direct the fetal head toward the birth canal at parturition |
|
|
Term
| Hirschprung’s disease is aka |
|
Definition
| congenital aganglionic megacolon |
|
|
Term
|
Definition
a section of the colon adjacent to the anus (usually <30 cm) contains no enteric ganglia
o leads to dilation of colon proximal to inactive segment |
|
|
Term
| What important symptom will a neonate with congenital Hirschprung's disease present? |
|
Definition
| will never have a first bowel movement (no meconium) |
|
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Term
| Congenital Hirschprung's disease results from failure of the __________________ cells to form the _________________________ in the last 30 cm (or less) of the rectum |
|
Definition
neural crest
myenteric plexus |
|
|
Term
| What is the most effective treatment for Hirschprung's disease? |
|
Definition
|
|
Term
|
Definition
| dilated internal & external venous plexuses around the rectum or anal canal |
|
|
Term
| Internal hemorrhoids occur above the ________ line, are covered with ___________, and their pain fiberes are carried by ___________ fibers of the ___________ nerves |
|
Definition
pectinate
mucous membrane
General Visceral Afferant (GVA) fibers of the sympathetic nerves |
|
|
Term
| the pectinate line is aka |
|
Definition
|
|
Term
| pectinate line (aka dentate line) |
|
Definition
| a line which divides the upper 2/3rds (visceral portion, which belongs to the intestine) and lower 1/3rd (somatic portion, which belongs to the perineum) of the anal canal. |
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Term
| External hemorrhoids occure below the __________ line and are covered by ________. Their pain fibers are carried by __________________ fibers of the ______________ nerves. |
|
Definition
pectinate line (dentate line)
General Somatic Afferent (GSA) fiberes of the inferior rectal nerves |
|
|
Term
| Which are usually more painful: internal or external homorrhoids? |
|
Definition
|
|
Term
| Portal hypertension can cause __________ in the rectum and/or anus. |
|
Definition
|
|
Term
|
Definition
| a condition in which the walls of the rectum protrude through the anus and become visible outside the body |
|
|
Term
| What commonly happens to the rectum in starvation, and why? |
|
Definition
| it prolapses because a layer of fatty tissue helps to support the rectum |
|
|
Term
|
Definition
| a slit-like crack or tear in the skin of the anal canal. |
|
|
Term
| What nerves provide sensory fibers to the anus below the dentate line? |
|
Definition
|
|
Term
| Where are anal fissures most likely to occur in the anus? |
|
Definition
| in the posterior midline, inferior to the anal valves |
|
|
Term
| Hard feces can cause _______________ in the anus of chronically constipated people |
|
Definition
|
|
Term
| perianal abscesses (aka anorectal abscess) |
|
Definition
| an pocket of infection in the soft tissues surrounding the anal canal; can start as inflammation of the anal sinuses |
|
|
Term
| signs & symptoms of perianal abscess |
|
Definition
| fullness and tenderness between the anus and the ischial tuberosity |
|
|
Term
| Where is the abdominal aorta relative to the inferior vena cava? |
|
Definition
| the aorta is left of the inferior vena cava |
|
|
Term
| What branch of the abdominal aorta supplies blood to the foregut? |
|
Definition
|
|
Term
| a large paired set of arteries that arise from each side of the aorta at ~L1 (in the transpyloric plane) |
|
Definition
|
|
Term
|
Definition
| a transverse plane that typically cuts through the pyloric sphincter of the stomach, the tips of the ninth costal cartilages and the lower border of L1 |
|
|
Term
| The gonadal artery is known as the ___________artery in females and the _________ artery. |
|
Definition
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