The lecture covers the evaluation and management of abdominal pain in emergency department patients, highlighting common causes, the importance of thorough history and physical examination, and the necessity for timely intervention. It details demographics, presenting symptoms, and an extensive differential diagnosis, emphasizing life-threatening conditions that could arise in various age groups. Key considerations such as pain assessment, diagnostic tests, and management approaches are also discussed to guide medical decision-making.

1. The ED Patient with
Abdominal Pain
Marion R. Sills, MD, MPH
Medical Student Lecture

2. Overview of ED Abdominal
Pain
• Epidemiology
• Extensive differential
• Timely identification of the acute abdomen is key
• Approach
• Manage pain first
• H&P is key (again!)

3. Epidemiology
• Common: 5% of all emergency department (ED) visits
• Varied presentations
• acute exacerbations of chronic problems (e.g., peptic disease,
pancreatitis in alcoholics, inflammatory bowel disease)
• acute surgical abdomens (e.g., appendicitis, ruptured bowel,
acute volvulus)
• also includes trauma (e.g., splenic rupture, hepatic laceration, small
bowel rupture)
• nonsurgical abdominal emergencies (e.g., gastritis, biliary colic,
gastroenteritis)
• Differential is extensive

4. Epidemiology: Age, Sex
• Most Common Diagnoses pts > 50
• Cholecystitis (21%)
• Nonspecific abdominal pain (16%)
• Appendicitis (15%)
• SBO (12%)
• Everything else (diverticulitis, hernia, cancer, vascular)
• Most Common Diagnoses pts < 50:
• Nonspecific Abdominal Pain ( ~40% )
• Appendicits (32%)
• Cholecystitis (6%)
• SBO and Pancreatitis (each ~ 2%)

5. Other Common Diagnoses
• Gastroenteritis*
• GERD
• Cholecystitis
• Appendicitis
• Obstruction
• Constipation*
• UTI*
• PID*
• Renal stones
• Intussusception
*often misdiagnosed in patients with another, more
significant abdominal pathology

6. H&P
• H&P are key
• guide workup
• narrow the extensive differential
• Labs and imaging are used to either support/refute your
suspected diagnosis
• More helpful in generating a diagnosis when the H&P is
suboptimal (altered, confused patient)

7. H&P: Key Considerations
• Essential to rule out the life-threatening causes
• AAA
• Perforation
• Obstruction
• Ischemia
• Ectopic pregnancy
• identify patterns that place a person at risk for life-threatening
causes and rule out/in those causes

8. H&P: Initial approach
• If on initial assessment the patient is in obvious pain, give
analgesia immediately
• Severe pain: parenteral administration
• Usually morphine sulfate
• If probable renal colic, consider ketorolac
• if low/borderline BP, consider shorter acting opioid: fentanyl
• Milder pain: oral medication may be OK
• Medications will not interfere with the exam
• If the vital signs are abnormal have low threshold for
obtaining vascular access

9. Abdominal Pain History
• HPI
• Onset
• Palliates/Provokes
• Quality
• Radiation
• Severity
• Time course
• Undo (what have they
done to “undo” their
pain)
• PMH
• PMHx
• Surgical Hx
• Allergies
• Meds
• Social Hx
• EtOH

10. History: Characterizing Pain
• Onset and pattern
• Location and radiation
• Alleviating and aggravating factors
• Severity
• Quality

11. History: Characterizing Pain
• Onset
• Abrupt or gradual onset (abrupt is worse)
• Duration (< 48 hours is worse)
• Trend and pattern: constant or intermittent (constant pain is
worse)
• Timing in relation to other symptoms (e.g., pain that precedes
vomiting is worse)
• Tip:
• Constant pain that began abruptly suggests renal colic,
perforated viscus, ischemia (myocardial infarction, testicular or
ovarian torsion) or hemorrhage

12. History: Characterizing Pain
• Location
• Ask where the pain is and how this has changed
• 6 anatomic locations: RUQ, epigastrium, LUQ, RLQ, suprapubic,
and LLQ
• Tips:
• The more midline the pain, the more likely it is bowel based
• Pain that starts centrally and migrates to the RLQ has a high
specificity for appendicitis
• Pain that localizes (in children, to somewhere other than umbilicus)
is of higher concern
• Radiation
• Can be helpful when present
• Tips:
• Radiating into back or groin suggests renal colic
• Radiating into right shoulder suggests biliary disease

13. Causes by Quadrant
RUQ LUQ
•Gastric/Peptic Ulcer
•Biliary Disease
•Hepatitis
•Pancreatitis
•Retrocecal Appendicitis
•Renal Stone
•Pyelonephritis
•MI
•Pulmonary Embolus
•Pneumonia
•Gastric Ulcer
•Gastritis
•Pancreatitis
•Splenic injury
•Renal Stone
•Pyelonephritis
•MI
•Pulmonary Embolus
•Pneumonia
RLQ LLQ
•Appendicitis
•Ovarian Cyst
•Mittelschmerz
•Pregnancy
•Tubo-ovarian abscess
•PID
•Ovarian Torsion
•Cystitis
•Prostatitis
•Ureteral Stone
•Testicular Torsion
•Epididymitis
•Diverticulitis
•AAA
•Diverticulitis
•Ovarian Cyst
•Mittelschmerz
•Pregnancy
•Tubo-ovarian abscess
•PID
•Ovarian Torsion
•Cystitis
•Prostatitis
•Ureteral Stone
•Testicular Torsion
•Epididymitis
•AAA

14. History: Characterizing Pain
• Alleviating and aggravating factors
• Include eating, movement, medication
• Tips:
• Worsened by eating: often related to pancreas or gall bladder
• Relieved by eating: often peptic disease.

15. History: Characterizing Pain
• Severity
• Evaluate with 1-10 scale
• Allows assessment of trends and response to therapy
• Quality
• Sometimes helpful, but some patients are highly suggestible, or
unable to describe pain very precisely.
• Tip: Ask if the patient had pain like this before. If yes, consider
peptic disease, biliary disease, IBD, hepatitis, and pancreatitis. (A
report of no prior episodes is worse)

16. History: Pain
Characterization and
Differential Diagnosis• Sudden onset of severe pain which does not diminish
• renal colic
• perforated viscous (e.g., ulcer)
• myocardial infarction, intestinal infarction
• torsion (ovary, testicle)
• hemorrhage (e.g., dissecting AAA)
• Crampy pain
• biliary colic
• renal colic
• intestinal obstruction
• gastroenteritis
• ectopic pregnancy
• Referred pain
• myocardial infarction may present as epigastric pain
• pneumonia
• strep tonsillitis

17. History: ROS
• General: Fever and chills point to an acute inflammatory
condition
• Respiratory: cough or dyspnea may point to pneumonia with
upper quadrant radiation
• GI:
• Anorexia: absence rules against an acute inflammatory condition
• Diarrhea suggests gastroenteritis but may be present with 20% of
acute appendicitis (be careful diagnosing gastroenteritis without
diarrhea)
• Ask about BMs, melena, hematochezia, straining
• GYN: ask about pregnancy, vaginal bleeding and discharge,
STDs and LMP
• GU: symptoms of UTIs—dysuria, frequency, and back pain

18. History: PMH
• PSH:
• Ask about prior abdominal surgeries
• Tip: Abdominal pain with vomiting, no flatus or BM, and a midline
abdominal scar suggests an SBO
• PMH:
• Ask about prior bowel problems
• History of vascular or heart disease, HTN or atrial fib increases
risk of mesenteric ischemia and abdominal aneurysm
• If history of cancer, diverticulosis, pancreatitis, kidney stones,
gallstones, or inflammatory bowel disease, consider recurrence
• In elderly/frail, DM and ESRD increase risk for ischemic bowel
• HIV increases risk for serious etiology (consider occult infection
or drug- related pancreatitis)

19. History: PMH
• Meds:
• consider iatrogenic causes of abdominal pain (e.g., erythromycin
at 500 mg BID causes abdominal pain in 50%)
• consider medications that may mask infection, such as antibiotics
or steroids
• Habits:
• Ask about alcohol and quantity of consumption, IV drug use,
cocaine/amphetamine
• Tip: Most alcoholics have some component of pancreatitis,
hepatitis and gastritis

20. History: Age
• Abdominal pain in the elderly:“an M&M waiting to happen”
• Mortality & misdiagnosis rise exponentially w/each decade >50
yrs.
• For those > 65 years, ~ 60-70% get admitted, 40-50% go to the
OR and 10% die (this is higher than mortality of acute MI at 6-8%)
• Elderly patients frequently get more testing

21. Physical Exam
• General characteristics
• overall appearance (key)
• level of distress (and response to analgesia)
• diaphoresis (concerning)
• VS (persistent fever, tachycardia, tachypnea, or hypotension are
concerning)
• body posture:
• writhing (suggests renal, biliary or intestinal colic)
• prefers to sit, leaning forward a little (suggests pericarditis or
pancreatitis)
• lying very quietly, often with hips and knees flexed, and does not like
to move (suggests peritonitis)

22. Physical Exam
• Non-abdomen features
• Lungs: rales
• Back: CVA tenderness
• OP: pharyngitis/tonsillitis

23. Physical Exam: Abdomen
• Peritoneal irritation (heel tap, jump, rock the bed, ask patient
to cough)
• Inspect abdomen for distention, ascites, contusions, incisions
• Auscultate for the presence and quality of bowel sounds
• Percuss to determine
• presence of percussion tenderness
• liver span
• Palpate to determine
• location of maximal tenderness
• presence or absence of guarding and/or rebound tenderness
• presence of masses, organomegaly and/or hernias
• start gently, away from the area of pain, distract the patient, and
then palpate more deeply

24. Physical Exam: Signs
• Murphy’s Sign
• arrest of inspiration with examiner’s palpating fingers in the RUQ
• suggests irritation in the RUQ
• always present in cholecystitis: may also occur with pancreatitis,
hepatitis and peptic disease
• Psoas Sign (extend patient’s leg at hip with patient in lateral
decubitus position (to move psoas muscle)
• Obturator sign (flex and externally and internally rotate hip)
• Rovsings Sign
• palpation in LLQ causes pain in RLQ
• suggests appendicitis

25. Rectal Exam
• Generally indicated only in those with symptoms referable to
the rectal/anal area or suspected GI bleeding, otherwise rarely
useful in generalized abdominal pain workup
• Prostatitis
• GI bleeding: upper or lower
• Hemorrhoids
• Constipation: possible impaction?
• Bloody diarrhea (enteritis)

26. Physical Exam: Down There
• Women (especially if they’ve had a pelvic exam before):
• at least a bimanual pelvic examination of women
• evaluate for cervical motion tenderness (PID) and adnexal masses
• Males: examine the testicles, scrotum, groin and prostate as
indicated

27. Diagnostic Testing
• Obtain tests
• if the diagnosis is not clinically apparent
• if the patient is sick
• if there is a suspected complication of a known diagnosis
(e.g.,rectal bleeding in IBD, fever in diverticulitis)
• Knowing that studies will only aid what you already suspect,
identify needed treatments and start them empirically as
indicated

28. Laboratory Studies
• CBC
• 10-60% of patients with appendicitis have a normal WBC count
• Elevated WBC count detects 53% of severe abdominal pathology
• WBC > 15K with abdominal pain raises risk. If a benign diagnosis
(gastroenteritis, renal colic) is not clear, consider imaging.
• Electrolytes, anion gap, BUN/Cr
• Lipase
• UA
• LFTs (transaminases, bilirubin, albumin, alk phos)
• Pregnancy Test!
• ECG (especially if > 40 years, in patients with DM and/or those with
epigastric pain)
• ABGs are indicated in patients who are elderly and in severe pain.
Acidosis suggests bowel ischemia.

29. Radiographic Studies
• Plain film: abdominal x-ray, chest x-ray
• Abdominal CT
• Abdominal ultrasound
• ERCP

30. Radiographic Studies: Plain
Film
• Mostly helpful in ED for:
– Free air (suspected perforation)
– Pneumatosis (typhlitis)
– Dilated loops of bowel with air fluid levels (obstruction)
– Foreign body
• Free air seen in only 30-50% of bowel perforation

31. Sigmoid Volvulus

32. Sigmoid Volvulus

33. What’s wrong with this picture?

34. Radiography: Ultrasound
• Excellent for biliary tract disease (90+% sensitive for
gallstones)
• AAA- can rapidly assess size at bedside
• Ectopic pregnancy- look for intrauterine yolk sac, assess
adnexa, assess for free fluid
• Appendicitis- 75%-90% sensitive (in experienced hands, best
in thin patients)
• Pelvic structures, testicles
• Can also assess intussusception, obstructive kidney stone

35. Gallstones

36. AAA

37. Radiology- CT Scan
• Detect leaking AAA (in stable patient)
• Evaluate for renal calculi, appendicitis, perforation (free air),
diverticulitis, abscess, mesenteric ischemia, masses, obstruction
• Sensitivity and specificity vary
• Not a place for unstable patients
• Contrast
• PO and IV contrast in most patients
• sometimes rectal contrast is helpful to look for large bowel problems
(appendicitis)
• In patients with renal insufficiency
• give IV contrast judiciously in patients
• consider ultrasound as an alternative if possible
• a creatinine > 1.5 usually requires bicarbonate and fluid hydration to
minimize contrast nephropathy

38. Kidney Stones- CT
Style

39. Sigmoid Tumor/Intussusception

40. Psoas Abscess

41. Retroperitoneal Abscess

42. TOA

43. Radiographic Studies: Other
• CXR—useful in upper quadrant pain
• ERCP—essential for common duct obstruction (gallstones,
sludge, compression, stricture)

44. General Management
• Fluids
• Most patients with serious abdominal pain are dehydrated
• Unless there is concern for fluid overload, give a bolus and then a
rapid infusion rate
• Analgesia—give ongoing pain relief with morphine in most
cases.
• Antibiotics for acute inflammatory processes (cholecystitis,
diverticulitis, appendicitis)
• NG tube—decompress the stomach for SBOs, ischemic bowel
or any serious condition with ileus
• Blood transfusion—Use in any symptomatic hemorrhagic
event, such as a ruptured AAA or GI bleed from an active ulcer
• Surgical consultation—obtain in patients with peritonitis,
hemorrhage, ischemia; consider with uncertain etiology

45. Case #1- Presentation
• 23 yo female
• acute onset LLQ pain 2 hours ago
• Constant, no radiation, no N/V/D
• No exacerbating, alleviating factors
• No vaginal discharge

46. Case #1 -PMH
• No medical problems
• No medications, No allergies
• Surg Hx: S/P Elective Abortion 1 year ago
• No history of STDs, Sexually Active
• LMP 4 weeks ago

47. Case #1- Exam
• Vitals: P105 R20 T37.7 BP 103/58
• Abd: soft, tender LLQ with guarding, no rebound pain
detected
• Pelvic: No cervical motion tenderness, L adnexal
tenderness/fullness
• Rectal: No masses, guaiac negative

48. Case #1- Differential Diagnosis
• ?

49. Case #1- Differential Diagnosis
• Ectopic Pregnancy
• Ovarian Cyst
• Tubo-ovarian abscess
• Ovarian Torsion

50. Case#1- Intervention/Diagnosis
• Pregnancy Test - Negative
• IV Fluids - 500 cc bolus ( repeat P 90, BP110/65 )
• U/S- L ovary with absent blood flow, multiple cysts
• Diagnosis: Ovarian Torsion
• Disposition: To OR by GYN

51. Case #2- Presentation
• 47 yo male with sudden onset abd pain
• Epigastric pain, vomited x2
• Pain 10/10
• Better if holds still, worse on car ride into hospital
• Never had pain like this before

52. Case #2- Past Medical History
• Medical Hx: Arthritis, Chronic Low Back Pain
• Surgical Hx: L knee meniscus repair
• Meds: No prescribed meds, OTC ibuprofen
• Allergies: NKDA
• SH: 2 beers/night

53. Case #2- Exam
• Vitals: P95 R22 T37.4 BP 124/75 O2 100%
• Gen: Anxious, Mild distress/diaphoretic, Remaining still
• Abd: Decreased BS, Severe epigastric tenderness with
guarding and rebound
• Rectal: Guaiac positive

54. Case #2- Actions
• Large bore IV x2, Type and Screen, CBC, CMP, Lipase, Fluid
bolus,ECG
• Acute Abdominal Series
• Orthostatic Vitals

56. Case #2 -
Interventions/Diagnosis
• CXR reveals intra-abdominal free air
• Diagnosis: Perforation, likely duodenal or gastric ulcer
• Disposition: To OR for identification and repair

57. Multiple Life Threatening Causes
of Abdominal Pain
• Identify the potential life threatening cause of the following
cases.
• Differential diagnosis is large but consider an acute event and
test your intuition

58. Rapid Cases #1
• 25 yo female
• Recurrent vomiting, diffuse mild pain
• Febrile, dehydrated, tachycardic
• H/O Diabetes Mellitus
• Diagnosis: DKA

59. Rapid Cases #2
• Healthy 17 yo male, football player
• L shoulder pain, not reproducible on exam
• lightheaded, weak
• U/S with free intraperitoneal fluid
• Diagnosis: Splenic Lac

60. Rapid Cases #3
• 16 yo female
• Nausea, diffuse discomfort starting yesterday
• Now worse RLQ
• Abd exam: pain RLQ, +guarding
• Diagnosis: Appendicitis

62. Rapid Case #4
• 65 yo male
• Hx of HTN, Renal Colic x3 episodes
• Low back pain- ?new pain
• Abd: obese, soft, no masses palpated
• U/S shows 7cm AAA

64. Rapid Case #5
• 56 yo female
• H/O Alcoholic Cirrhosis
• Diffuse abd pain, gradual onset
• Distended abdomen, febrile
• U/S: ascites
• Peritoneal tap >500 WBC/cc
• Spontaneous Bacterial Peritonitis

65. Rapid Case #6
• 32 yo female, S/P Tubal ligation 2 weeks ago
• Gradual onset diffuse pain
• N/V/D, fever
• Diffusely tender, guarding, + rebound
• CXR with free air
• Bowel perforation

66. Free Air

67. Rapid Case #7
• 82 yo male S/P distant chole, appy
• Gradual onset vomiting, nausea, distension
• Distended abdomen, increased bowel sounds
• KUB: multiple air fluid levels, dilated loops of small bowel
• Small Bowel Obstruction

68. Small Bowel Obstruction

69. Rapid Case #8
• 16 yo male
• sudden onset lower abd, scrotal pain
• No hx of trauma
• Tender L testicle to exam
• U/S: No vascular flow to L testicle
• Acute Testicular Torsion

70. Rapid Case #9
• 30 yo female, G3P3 IUD in place
• LLQ pain, gradually worsening today
• No fever, Tender L Adnexa
• + UPT
• U/S with L Adnexal Gestational Sac
• Ectopic Pregnancy

71. Rapid Case #10
• 4 yo male
• Crampy abdominal pain- crying
• Tender diffusely to exam, afebrile
• Guaiac positive stool
• Complete relief with enema
• Intussusception

72. Intussusception

73. Rapid Case #11
• 23 yo healthy female
• Severe lower abdominal pain
• Gradual onset, no N/V/D
• Abd Tender Bilateral Lower Quadrants
• Cervix tender with movement, UPT -
• Dx: PID

74. Rapid Case #12
• 82 yo Female
• H/O HTN, A. Fib, CAD, COPD
• Acute severe diffuse abd pain
• Exam: Soft, minimal tenderness to palpation
• Angiography reveals occluded SMA
• DX: Mesenteric Ischemia

75. Rapid Case #13
• 46 yo female, G3P3
• Post Prandial Epigastric pain
• Exam: Obese, RUQ tender to palpation
• U/S: Multiple Gallstones with GB wall thickening
• DX: Acute Cholecystitis

76. Acute Cholecystitis

77. Rapid Case #14
• 78 yo male
• H/O HTN, DM
• Acute onset nausea, diaphoresis, epigastric discomfort,
• Exam: Mild epigastric discomfort to palpation
• ECG ST elevation 3mm leads II, III aVF
• Dx: Inferior MI

78. Inferior STEMI

79. Rapid Case # 15
• 65 yo female
• LLQ pain, gradually worsening
• Exam: Febrile, Tender LLQ to palpation
• Guaiac + stool
• CT: Diverticulitis with multiple microperforations
• Dx: Acute Diverticulitis

80. Do you see the free air?

82. Rapid Case #16
• 52 yo alcoholic male
• Diffuse abd pain, gradually worsening, vomiting recurrently
• Exam: soft abdomen, minimal tenderness
• Labs: Increased lipase
• Dx: Pancreatitis

83. Rapid Case #17
• 14 yo healthy male
• Acute crampy abd pain past day
• Vomiting, Diaphoretic
• Exam: Diffuse mildly tender abdomen with palpable firm mass
in R groin
• Dx: Incarcerated inguinal hernia

84. Incarcerated Hernia

85. Rapid Case #18
• 28 yo post-partum healthy female
• Acute R flank pain radiating to groin
• Exam: Abd soft, non-tender without CVA tenderness
• UA with 2+ RBC, no WBCs
• CT with R Ureteral Calculi
• Dx: Renal Colic

86. Hydronephrosis

87. Renal Calculus

88. Hydro-ureter

89. UVJ Stone

90. Rapid Case #19
• 72 yo female c/o RUQ pain & cough
• PMHx: HTN, COPD on home O2
• Vitals: T38.5 HR 105 RR 26 BP 140/90 SpO2 88% on 2L
• Physical: dry mucous membranes, decreased breath sounds,
non-tender abdomen
• CXR: RLL infiltrate
• Diagnosis: RLL pneumonia

93. Summary
• The Differential Diagnosis of Abdominal Pain is extensive.
Large. Massive even.
• You need to identify patterns that place a person at risk for
serious causes of their pain and rule out/in those causes
• History and Physical are the key to narrowing the ddx
• Labs and Radiology support/refute your diagnosis

94. Summary Continued
• Always get Pregnancy Test (doesn’t matter if they are on
OCP’s, had a tubal ligation, or swear they can’t be pregnant
due to saintly behavior-OK, no, if hysterectomy or elderly)
• If discharging a patient, always alert patient of symptoms they
should watch for and when to return
• If dx is “abdominal pain NOS” (unknown etiology), consider
f/u, even in ED, for re-evaluation