10/12- Abdominal Pain and Constipation Flashcards Preview

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

How is pain sensed in the diaphragm?

  • Receptors
  • Stimuli
  • Sensation
A

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
Q

Describe abdominal pain due to visceral receptors?

A
  • 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
Q

Describe somatic/parietal pain

  • Nerve fibers involved
  • Location
  • Sensation
  • Aggravated by
  • Location
A
  • 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
Q

What are reflexive responses to somatic/parietal abdominal pain?

A
  • Involuntary guarding
  • Abdominal rigidity
5
Q

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

A

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
Q

What causes referred pain?

  • What neurons involved
  • What may cause it
A
  • 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
Q

How does localization vary by cause with abdominal pain?

A
  • Visceral pain: localization unreliable
  • Parietal pain: reliable location
  • Most organs are bilaterally, symmetrically innervated

(EXCEPT: gallbladder, ascending/descending colon)

8
Q

Difference between acute/chronic or recurrent abdominal pain?

A
  • Acute = under 24 hrs, usually sudden onset
9
Q

Rigidity upon palpation of the abdomen suggests what?

A

Peritonitis

10
Q

Rebound tenderness suggests what?

A

Peritonitis

11
Q

Absence of bowel sounds may indicate what conditions?

A
  • Peritonitis
  • Perforation
  • Obstruction
12
Q

High pitched bowel sounds may indicate what?

A
  • SBO
  • Ileus
13
Q

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

A
  • CBC: anemia, leukocytosis, leukopenia
  • CMP: assess metabolic state, assess hepatobiliary disease
  • Lipase (amylase): elevated in acute pancreatitis
  • Pregnancy test for childbearing age women
14
Q

When is x-ray useful in evaluating abdominal pain?

A

“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
Q

When is US useful in evaluating abdominal pain?

A
  • Cholelithiasis
  • Biliary evaluation
  • Abscesses
  • Aortic aneurysm
  • Ectopic pregnancy

Pros: readily available, inexpensive

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

16
Q

When is CT useful in evaluating abdominal pain?

A

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
Q

What is the key demographic for biliary disease?

A

4Fs:

  • Fat
  • Forty
  • Female
  • Fertile
18
Q

Where is pain from biliary disease experienced?

A

Postprandial RUQ pain

  • Biliary colic intermittent
19
Q

What are types of biliary disease/co-conditions?

A

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
Q

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

A

Cholangitis

21
Q

Causes of upper abdominal pain?

A

Biliary disease

  • Acute cholecystitis
  • Choledocholithiasis
  • Cholangitis

Peptic ulcer disease

Acute pancreatitis

22
Q

Describe peptic ulcer disease?

  • Location
  • Improved when
  • Complications
  • Signs
A
  • Epigastric, improved after eating
  • “Acute abdomen” if perforated Peritonitis/Peritoneal signs
  • Rigid abdomen
  • Lack of bowel sounds
23
Q

Describe peptic ulcer disease

  • Most common causes
  • Presentation
  • Diagnostic criteria

Treatment

A

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
Q

What may cause lower abdominal pain?

A
  • Appendicitis
  • Diverticulitis

Diffuse abdominal pain sydnromes:

  • Mesenteric ischemia
  • Mesenteric embolism
  • Mesenteric thrombosis
  • Low flow mesenteric ischemia
  • Small bowel obstruction
25
Q

Describe appendicitis

  • What is it
  • Presentation
  • Diagnosis
  • Treatment
A
  • # 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
Q

Describe diverticulitis

  • Disease progression
  • What is it
  • Complications
  • Presentation
  • Treatment
A
  • 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
Q

What are some causes of diffuse abdominal pain syndromes?

A
  • Mesenteric ischemia (embolism)
28
Q

Describe mesenteric ischemia/embolism

  • Most common causes
  • Presentation
  • Exam findings
  • Complications
A
  • 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
Q

Describe mesenteric thrombosis

  • Causes
  • Presentation
A

Due to:

  • Atherosclerosis, usually at SMA

May describe:

  • Intestinal angina
  • Weight loss
30
Q

Describe low flow mesenteric ischemia:

  • Causes
  • Presentation
A
  • Reduced cardiac output
  • Shock
  • Dehydration
31
Q

Describe small bowel obstruction:

  • Causes
  • Presentation
  • Diagnosis
  • Treatment
A
  • 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
Q

What is normal as far as bowel habits?

A
  • 2-3/day to 3/week
  • Should be easy to pass
  • Should feel relieved afterward
33
Q

Pathophysiology of constipation: secondary?

  • Colon disorders
  • Metabolic disturbances
  • Neurologic disorders
  • Medications
A

Colon disorders:

  • Strictures
  • Anal fissure
  • Proctitis

Metabolic disturbances:

  • Hypercalcemia
  • Hypothyroidism
  • Diabetes

Neurologic disorders:

  • Parkinsonism
  • Spinal cord lesions

Medications:

  • Antacids
  • Opiates
  • Iron
  • CCBs
34
Q

Pathophysiology of constipation: idiopathic?

A
  • Slow transit
  • Functional outlet obstruction
35
Q

Describe slow transit as a cause of idiopathic constipation

A
  • 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
Q

Describe functional outlet obstruction as a cause of idiopathic constipation

A
  • Ineffective opening of the anal canal or failure of the rectum to expel feces
  • Pelvic floor dysfuction: lack of coordination or altered anatomy
37
Q

What are alarm symptoms when working up constipation?

A
  • Blood in the stool
  • Weight loss
  • Sudden onset of symptoms
38
Q

What should be done on PE for constipation work up?

A

Abdominal exam:

  • Distension
  • Tenderness
  • Fecal column

Anorectal exam:

  • Examine perineum
  • Cutaneoanal reflex (“anal wink”)
  • Rectal mass
39
Q

What labs should be run when working up constipation?

A
  • CBC: check for anemia
  • BMP: hypkalemia, hypercalcemia, diabetes
  • TSH
  • Not necessary in all pts
40
Q

When should endoscopy and imaging be done for constipated pts?

A

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
Q

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

A

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
Q

How can constipation be treated?

A

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
Q

What are different laxatives/strategies?

A

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
Q

How can you use biofeedback to treat constipation?

A

Pelvic floor dysfunction patients

Attempt regular defecation schedule

  • Use suppositories or enemas
  • Reward success

Biofeedback

  • Relearn to interpret sensation
45
Q

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

A

Lubiprostone- opens chloride channels and increases luminal fluid secretion

46
Q

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

A
  • Methylnaltrexone in opiate induced constipation
  • Blocks opiate receptors on the GI tract
47
Q

What surgeries may be done to treat constipation?

A
  • Colonic inertia
  • Colectomy