S09C74 - Acute Abdominal Pain

Question 1

Visceral abdo pain

Answer 1

• caused by stretching of nerves in the walls and capsules of organs
• vague, generalized pain
• foregut (stomach, liver, GB, pancreas, 1/2 duo) = epigastric
• midgut (3/4 duo, jej, ileum, cecum, appy, asc colon, 2/3 transverse colon) = periumbilical
• hindgut (1/3 transverse, desc colon, sigmoid, rectum, intraperitoneal GU organs = suprapubic)
• b/l innervation so pain is felt in midline (eg. appy is midline of T10)
• colickly like pain

Question 2

Parietal pain (somatic)

Answer 2

Irritation of myelinated fibers that innervate the parietal peritoneum

• localized to dermatome superficial to the site of painful stimulus
• tenderness and guarding, rigidity, rebound

Question 3

Referred pain

Answer 3

• based on embryology

- eg. ureter and testes have same segmental innervation

Question 4

Red flags for critically ill pts presenting with abdo pain:

Answer 4

• extremes of age
• severe pain with rapid onset
• abnormal vital signs
• dehydration
• pallor, diaphoresis, vomiting
• rapid onset of shock is usually d/t intra-abdominal hemorrhage
• BP may not drop until blood loss reaches 30-40% of normal blood volume

-incr of HR by 30 or near-syncope after standing for 1 min represents 1L of blood loss

Question 5

Lab work for critically ill abdo pt:

Answer 5

• CBC
• lytes, BUN, Cr, glucose
• coags
• type and screen
• hcg for women
• liver enzymes
• lipase
• u/a

Question 6

Distension =

Answer 6

-ascites, ileus, obstruction, volvulus

Question 7

Mass =

Answer 7

-hernia, tumor, aneurysm, distended bladder

Question 8

Hyperactive bowel sounds =

Answer 8

-SBO

Question 9

> 50yo with abdo pain

Answer 9

-must always r/o AAA

Question 10

Female and lower abdo pain

Answer 10

-everyone should get a pelvic

Question 11

Male and lower abdo pain

Answer 11

-testicular and prostate exam should be done

Question 12

Pain management

Answer 12

-opioid analgesia does not obscure findings, delay dx or cause incr morbidity/mortality

Question 13

Abdo pain ddx by area (less commonly thought of):

Answer 13

generalized:
- diabetic gastric paresis
- familial mediterranean fever
- heavy metal poisoning
- hereditary angioedema
- malaria
- metabolic - addisonian crisis, AKA, DKA, porphyria, uremia
- narcotic w/d
- sickle cell crisis

RUQ:

• hepatic abscess-
• herpes zoster

RLQ:

• endometriosis
• epiploic appendagitis
• hernia
• ischemic colitis
• meckel diverticulum
• psoas abscess

LUQ:
-splenic rupture/distension

LLQ:

• endometriosis
• epiploic appendagitis

Question 14

Pain with n/v and rigidity:

Answer 14

• acute pancreatitis
• diabetic gastric paresis
• DKA
• incarcerated hernia

Question 15

Pain/shock

Answer 15

• abdo sepsis
• Ao dissection
• hemorrhagic pancreatitis
• leaking AAA
• mesenteric ischemia
• MI
• ruptured ectopic

Question 16

Pain, n/v, distension ddx:

Answer 16

• obstruction

- cecal volvulus

Question 17

Pain, shock, rigidity

Answer 17

• perforated appy
• perforated diverticulum
• perforated ulcer
• ruptured esophagus
• splenic rupture

Question 18

Pain and n/v ddx:

Answer 18

• acute diverticulitis
• adnexal torsion
• mesenteric ischemia
• myocardial ischemia
• testicular torsion

Question 19

Plain abdo series, indication and sensitivity:

Answer 19

• mostly used for detecting perforation
• 20% of pts with perforation will not demonstrate free air
• restrict AXR to pts with suspicion of obstruction, perforation or severe constipation
• u/s may be better for detection of free air!

Question 20

U/s indications

Answer 20

-use for pts with suspected biliary tract dz

Question 21

ECG

Answer 21

-consider if upper abdo pain and pts >40y

Question 22

Appendicitis

Answer 22

• peak age adolescence and young adults

- CT preferred for dx in adults and non-pregnant pts

Question 23

Biliary colic

Answer 23

• F»M before 60yo

- colic pain usually resolves in

Question 24

Bladder outlet obstruction

Answer 24

• BPH

- dx with u/s

Question 25

Bowel obstruction

Answer 25

- plain films 77% sens - CT 93% sens - complications: incarceration, strangulation

Question 26

Cholecystitis

Answer 26

- 90% afebrile - incr WBC in 63% - incr WBC in 80% if cholangitis - incr bili/AST/ALT/ALP - u/s 91% sensitive - complications: common bile duct obstruction, asc cholangitis, gangrene

Question 27

Diverticulitis

Answer 27

- M>F before 40yo - sigmoid in 85% of cases, otheres are cecal, meckal, RLQ - 25% will have + FOB - CT 93-100% sn, highly sp - complications: perforation, abscess, fistula, obstruction

Question 28

Epiploic appendagitis

Answer 28

- middle age - M>F - LLQ - fever unusual, n/v infrequent, diarrhea 25% - dx: CT

Question 29

Mesenteric arterial occlusion

Answer 29

- n/v, diarrhea - lactate 75-90% sn - elevated WBC 90% - CT angio 96% sn

Question 30

Mesenteric venous thrombosis

Answer 30

- occurs in hypercoagulable states and liver dz | - CT with contrast to dx

Question 31

Pancreatitis

Answer 31

- M>F - EtOH, biliary dz, drugs, ERCP - lipase is 90% sn in first 24h - CT 78%sn, 86% sp - complications: hemorrhage, pseudocyst, ARDS, sepsis

Question 32

PUD

Answer 32

-RF: peak age 50s, M>F, ASA/NSAID use, smoking, EtOH, h.py

Question 33

Renal/ureteral colic

Answer 33

- RF: 30-40yo, FmHx - 85-90% have hematuria - Dx: u/a, sprial CT - complications: obstruction, infxn

Question 34

Abx for intra-abdominal infections:

Answer 34

-should target anaerobes and facultative aerobic gm- -if SBP - need gm+ coverage for pneumococcus -traditional tx: gentamicin/tobramycin plus flagyl/clinda -suspected biliary sepsis: pip-tazo or imipenem -SBP: CTX -PID: CTX 250mg IM once plus doxy 100mg BID x14d +/- flagyl 500mg PO BID for mild infxn in-pt cefoxitin plus doxy or clinda plus genta

Question 35

Ectopic pregnancy

Answer 35

- pain in almost all cases - PV bleed in 90% of cases - all child-bearing age women with abdo pain should have a bHcG done, if positive then do an u/s - if b-hCG is >1500mIU/mL a gestational sac should be visible - in pts not undergoing infertility tx, visualization of an intrauterine pregnancy in 2 perpendicualr views excludes an ectopic pregnancy - 2 b-hCG 48h apart that rises

Question 36

PID

Answer 36

- occurs in 40% of women infected with STI - 20% of women with PID will get infertility from tubal scarring, 9% will have an ectopic pregnancy, 18% will get chronic pelvic pain - 50% gonorrhea/70% chlam. infxn in wmn are asymptomatic

Question 37

Post bypass complications:

Answer 37

- dumping syndrome - post-prandial gastric emptying, increased gastric homrones and splanchnic vasodilation - Sx: n/v, bloating, abdo cramps, diarrhea, sweating 30-60mins post meal - late dumping is 1-4h after eating - hyperinsulinemic and hypoglycemic - avoid highly concentrated foods and separate eating and drinking - tx: ocreotide -enteric leak can occur and presents like sepsis

Question 38

Epiploic Appendagitis

Answer 38

- appendages are mostly found on sigmoid and cecum, unknown fxn - self-limited, usually caused by torsion - usually middle-aged man with LLQ pain, usually no feveri, diarrhea in 25% of cases, n/v rare - tx: analgesia, ost resolve spontaneously in 1-2w

Question 39

Clostridium Difficile

Answer 39

- anaerobic, gm+, spore-forming bacillus - causes: severe diarrhea, pseudomembranous colitis, toxic megacolon, sepsis, death - pathophys: fecal-oral transmission, release of clostridial toxins, intestinal imflm - RF: >65y, illness, NG intubation, antiulcer Rx, Abx, long hospital stay - usually begins 4-5d after Abx Tx - common Abx assoc: amox, ampic, cephalosporins, clindamycin, quinolones - Sx: mild/mod nonbloody diarrhea to perfuse diarrhea hemoccult +, abdo pain, distension, fever, nausea - high WBC in fulminant dz - Dx: enzyme immunosorbent assay has 80% Sn for A and 95% for B, or can do an anaerobic stool Cx - Tx: stop inciting Abx, oral flagyl 250mg QID or 500mg TID x10d - severe dz: oral vanco 500mg QID x10d - colectomy for toxic megacolon