10/12- Abdominal Pain and Constipation Flashcards Preview

MS2 GI > 10/12- Abdominal Pain and Constipation > Flashcards

Flashcards in 10/12- Abdominal Pain and Constipation Deck (47)
1

How is pain sensed in the diaphragm?

- Receptors

- Stimuli

- Sensation

Mechanoreceptors (stretch)

- Torsion, rapid distention of a hollow viscus, forceful muscular contractions, and rapid stretching of solid organ serosa or capsule

Chemoreceptors

- Substances released in response to local mech injury, inflammation, ischemia, necrosis

- Chemical substances released include: H+ and K+ ions, histamine, serotonin, bradykinin and other vasoactive amines, substance P, calcitonin gene-related peptide, prostaglandins, and leukotrienes

Sensed as:

- Dull, cramping, burning, poorly localized, and more gradual in onset and longer in duration than somatic pain

- Secondary autonomic effects such as sweating, restlessness, nausea, vomiting, perspiration, and pallor often accompany

2

Describe abdominal pain due to visceral receptors?

- Abdominal organs transmit sensory afferents to both sides of the spinal cord

- Visceral pain is usually perceived to be in the midline, in the epigastrium, periumbilical region, or hypogastrium

3

Describe somatic/parietal pain

- Nerve fibers involved

- Location

- Sensation

- Aggravated by

- Location

- A-delta fibers

- Abdominal wall and peritoneum

- More intense, sharp, sudden, well-localized pain

- Aggravated by movement or vibration

- Lateralization possible because each side separately innervated

4

What are reflexive responses to somatic/parietal abdominal pain?

- Involuntary guarding

- Abdominal rigidity

5

How can quality of pain give you a clue to the cause of the abdominal pain?

Obstruction of Viscera

- Crampy, but can be constant

- Diffuse, or periumbilical if of small bowel

Peritonitis

- Steady, achy

- Directly over inflamed area

- Better with laying still

6

What causes referred pain?

- What neurons involved

- What may cause it

- Visceral afferent neurons and somatic afferent neurons from different area converge on second order neurons

- May have embryological origin

CAUSES:

- Cholecystitis -> shoulders or scapula

- Pancreatitis and perforated GU -> back

- Abdominal pain from non-abdominal organs

  • Zoster -> Abdominal wall pain
  • MI -> Epigastric pain
  • MI or pneumonia -> Upper abdominal pain

7

How does localization vary by cause with abdominal pain?

- Visceral pain: localization unreliable

- Parietal pain: reliable location

- Most organs are bilaterally, symmetrically innervated

(EXCEPT: gallbladder, ascending/descending colon)

8

Difference between acute/chronic or recurrent abdominal pain?

- Acute = under 24 hrs, usually sudden onset

9

Rigidity upon palpation of the abdomen suggests what?

Peritonitis

10

Rebound tenderness suggests what?

Peritonitis

11

Absence of bowel sounds may indicate what conditions?

- Peritonitis

- Perforation

- Obstruction

12

High pitched bowel sounds may indicate what?

- SBO

- Ileus

13

What to look for on lab testing when working up abdominal pain?

- CBC: anemia, leukocytosis, leukopenia

- CMP: assess metabolic state, assess hepatobiliary disease

- Lipase (amylase): elevated in acute pancreatitis

- Pregnancy test for childbearing age women

14

When is x-ray useful in evaluating abdominal pain?

“Acute Abdominal Series”: Upright chest, Upright abd film, Supine abd film

Useful in:

- Suspected perforation

- Bowel obstruction

- Severe constipation

- Kidney stones

- Colonic pseudo-obstruction

- Sigmoid volvulus

Pros: fast, inexpensive, widely available

Cons: limited view

15

When is US useful in evaluating abdominal pain?

- Cholelithiasis

- Biliary evaluation

- Abscesses

- Aortic aneurysm

- Ectopic pregnancy

Pros: readily available, inexpensive

Cons: limited evaluation, operator dependent, can be time consuming

16

When is CT useful in evaluating abdominal pain?

Chest, Abdomen, Pelvis

Useful in:

- Pancreatic disease

- Retroperitoneal collections

- Intra-abdominal abcess

- Some vascular processes

- Trauma-induced hematomas

- Ischemia

- Inflammation (IBD, Diverticulitis)

Pros: excellent images, widely accessible, relatively fast

Cons: Expensive, radiation exposure

17

What is the key demographic for biliary disease?

4Fs:

- Fat

- Forty

- Female

- Fertile

18

Where is pain from biliary disease experienced?

Postprandial RUQ pain

- Biliary colic intermittent

19

What are types of biliary disease/co-conditions?

Acute cholecystitis

- 95% due to cholelithiasis

- Obstruction of the gallbladder leads to inflammation

Choledocholithiasis

- Stone in CBD

- Can cause pancreatitis

Cholangitis

- Charcot's triad: pain, jaundice, fever

- Reynold's pentad: triad + hypoTN and change in mental status

20

In what condition is Charcot's triad/Reynold's pentad observed?

Cholangitis

21

Causes of upper abdominal pain?

Biliary disease

- Acute cholecystitis

- Choledocholithiasis

- Cholangitis

Peptic ulcer disease

Acute pancreatitis

22

Describe peptic ulcer disease?

- Location

- Improved when

- Complications

- Signs

- Epigastric, improved after eating

- “Acute abdomen” if perforated Peritonitis/Peritoneal signs

- Rigid abdomen

- Lack of bowel sounds

23

Describe peptic ulcer disease

- Most common causes

- Presentation

- Diagnostic criteria

Treatment

Most common causes:

- ETOH

- Gallstones

Presents with

- Epigastric pain radiating to the back

- Associated nausea and vomiting

Diagnostic criteria

- Elevated lipase (amylase)

- Clinical presentation

- CT characteristic findings

Treatment:

- IVF

- Opiates

24

What may cause lower abdominal pain?

- Appendicitis

- Diverticulitis

Diffuse abdominal pain sydnromes:

- Mesenteric ischemia

  • Mesenteric embolism
  • Mesenteric thrombosis
  • Low flow mesenteric ischemia

- Small bowel obstruction

25

Describe appendicitis

- What is it

- Presentation

- Diagnosis

- Treatment

- #1 cause of acute abdominal pain in US

- Obstruction and inflammation of appendix

Presents with

- Periumbilical pain, anorexia, +/- vomiting

- Pain migrates to right lower quadrant

Diagnose by clinical presentation and imaging

Treatment is surgical

26

Describe diverticulitis

- Disease progression

- What is it

- Complications

- Presentation

- Treatment

- Diverticulosis common, diverticulitis rare (5%)

- Occurs when diverticulum is obstructed with stool causing inflammation

- Usually sigmoid

- May progress to peritonitis or abscess: “complicated”

Presents with

- Left lower quadrant pain, fever, obstipation

- Leukocytosis

Treatment:

- NPO

- Antibiotics

27

What are some causes of diffuse abdominal pain syndromes?

- Mesenteric ischemia (embolism)

28

Describe mesenteric ischemia/embolism

- Most common causes

- Presentation

- Exam findings

- Complications

- Usually cardiac in origin: a.fib, mural thrombus

Presents with

- Sudden, severe abdominal pain

- Vomiting

Early examination unremarkable (pain out of proportion to examination)

May develop:

- Acidosis

- Infarction

- Leukocytosis

29

Describe mesenteric thrombosis

- Causes

- Presentation

Due to:

- Atherosclerosis, usually at SMA

May describe:

- Intestinal angina

- Weight loss

30

Describe low flow mesenteric ischemia:

- Causes

- Presentation

- Reduced cardiac output

- Shock

- Dehydration

31

Describe small bowel obstruction:

- Causes

- Presentation

- Diagnosis

- Treatment

- Usually from postoperative adhesions

- Malignancy, volvulus, intussusception

Presents with

- Crampy, intermittent, midabdominal pain

- Vomiting

- Abdominal distension

- Obstipation

Acute abdominal series: dilated loops of small bowel with air-fluid levels

Treatment:

- NPO

- IV hydration

- NGT

….surgery

32

What is normal as far as bowel habits?

- 2-3/day to 3/week

- Should be easy to pass

- Should feel relieved afterward

33

Pathophysiology of constipation: secondary?

- Colon disorders

- Metabolic disturbances

- Neurologic disorders

- Medications

Colon disorders:

- Strictures

- Anal fissure

- Proctitis

Metabolic disturbances:

- Hypercalcemia

- Hypothyroidism

- Diabetes

Neurologic disorders:

- Parkinsonism

- Spinal cord lesions

Medications:

- Antacids

- Opiates

- Iron

- CCBs

34

Pathophysiology of constipation: idiopathic?

- Slow transit

- Functional outlet obstruction

35

Describe slow transit as a cause of idiopathic constipation

- Likely dysfunction of enteric smooth muscles or nerves

- Usually longstanding

- Longer exposure to mucosa will allow for more water absorption and fermentation by bacteria

  • Scybala
  • Bloating

36

Describe functional outlet obstruction as a cause of idiopathic constipation

- Ineffective opening of the anal canal or failure of the rectum to expel feces

- Pelvic floor dysfuction: lack of coordination or altered anatomy

37

What are alarm symptoms when working up constipation?

- Blood in the stool

- Weight loss

- Sudden onset of symptoms

38

What should be done on PE for constipation work up?

Abdominal exam:

- Distension

- Tenderness

- Fecal column

Anorectal exam:

- Examine perineum

- Cutaneoanal reflex ("anal wink")

- Rectal mass

39

What labs should be run when working up constipation?

- CBC: check for anemia

- BMP: hypkalemia, hypercalcemia, diabetes

- TSH

- Not necessary in all pts

40

When should endoscopy and imaging be done for constipated pts?

No need unless alarm symptoms

- If rectal bleeding in pt under 45 yo (do sigmoidoscopy to rule out malignancy)

- If alarm symptoms (bleeding, weight loss) or age > 50, do colonoscopy

- KUB can be done to evaluate for fecal loading

41

What should be done for constipated pt if therapeutic trial does not yield improvement?

Sitz Marker study

- Capsule with markers ingested and then serial xrays

- If markers throughout the colon -> slow transit

- If markers in rectum -> pelvic floor dysfunction

Defecography

Anorectal manometry

42

How can constipation be treated?

Fiber

- Dietary is difficult (20-30 g/day)

- Supplementation

- May cause gas and distension

Increase fluid and exercise

- Good idea, but no evidence

Laxatives

Biofeedback

- Pelvic floor dysfunction pts

- Attempt regular defecation schedule

- Biofeedback

Other:

- Chloride secretagogues

- Systemic agents

- Surgery

43

What are different laxatives/strategies?

BULK

- Psyllium

- Methycellulose

- Wheat dextrin

Emollient

- Docusates

- Mineral Oil

Osmotic

- Mg hydroxide

- Phosphate salts

- Lactulose

- Sorbitol

- Polyethylene glycol

Stimulants

- Castor Oil

- Cascara fluid extract

- Senna

- Bisacodyl

44

How can you use biofeedback to treat constipation?

Pelvic floor dysfunction patients

Attempt regular defecation schedule

- Use suppositories or enemas

- Reward success

Biofeedback

- Relearn to interpret sensation

45

What are chloride secretagogues and how do they help in treating constipation?

Lubiprostone- opens chloride channels and increases luminal fluid secretion

46

What are systemic agents and how do they help in treating constipation?

- Methylnaltrexone in opiate induced constipation

- Blocks opiate receptors on the GI tract

47

What surgeries may be done to treat constipation?

- Colonic inertia

- Colectomy