Abdominal Pain (Undifferentiated)MANAGEMENT

GASTROINTESTINAL PRESENTATIONS · 12 SECTIONS

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605 items

☷ Legend

01Approach to the Critical Patient/attcp57

Immediate priorities

›Airway breathing circulation threats

›Hemodynamic instability

›SBP < 90 mmHg

›HR > 120 beats/min

›MAP < 65 mmHg

›Shock from occult hemorrhage

›Ruptured abdominal aortic aneurysm

›Ruptured ectopic pregnancy

›Massive GI bleed

›If unstable, resuscitate before diagnostic workup

›Two large bore IV lines

›Type and crossmatch

›Activate massive transfusion if hemorrhagic shock

›Cannot-miss time-critical diagnoses

›Mesenteric ischemia

›Pain out of proportion to exam

›Mortality 60% to 80% if delayed

›Perforated viscus

›Sudden severe pain with rigid abdomen

›Free air on imaging

›Ruptured AAA

›Sudden abdominal or back pain with hypotension

›Pulsatile mass

›Early branching on stability

›Stable patient

›Structured history and exam first

›Targeted labs and imaging

02History/hx87

Pain characterization

›Onset and progression

›Sudden maximal onset

›Perforation

›Ruptured AAA

›Volvulus or ischemia

›Gradual onset

›Appendicitis

›Cholecystitis

›Diverticulitis

›Colicky waxing and waning

›Urolithiasis

›Biliary colic

›Bowel obstruction

›Location and radiation

›Right upper quadrant

›Biliary disease

›Hepatitis

›Right lower lobe pneumonia

›Epigastric

›Peptic ulcer disease

›Pancreatitis

›Inferior myocardial infarction

›Right lower quadrant

›Appendicitis

›Meckel diverticulum

›Ovarian torsion

›Left lower quadrant

03Physical Exam/exam55

Vital signs and general appearance

›Hemodynamic snapshot

›Blood pressure

›SBP < 90 mmHg as shock marker

›Narrow pulse pressure

›Heart rate

›Tachycardia as early shock sign

›Irregular rhythm suggesting atrial fibrillation

›Temperature

›Fever in infection or inflammation

›Hypothermia in severe sepsis

›General state

›Distress and positioning

›Lying still in peritonitis

›Writhing in colic

›Pallor and diaphoresis

›Hemorrhage or ischemia concern

Abdominal examination

›Inspection and auscultation

›Distension

›Bowel obstruction

›Ascites

›Visible pulsatile mass

›AAA concern

›Bowel sounds

›High-pitched in obstruction

›Absent in ischemia or strangulated obstruction

›Palpation findings

04Differential Diagnosis/ddx58

Cannot-miss diagnoses

›Vascular catastrophes

›Ruptured AAA

›ICD-10 I71.3

›Sudden pain with hypotension and pulsatile mass

›Mesenteric ischemia

›ICD-10 K55.0

›Pain out of proportion with elevated lactate

›Surgical emergencies

›Perforated viscus

›ICD-10 K63.1

›Rigid abdomen with free air

›Bowel obstruction with strangulation

›ICD-10 K56.69

›Obstipation and distension with absent bowel sounds

›Reproductive emergencies

›Ruptured ectopic pregnancy

›ICD-10 O00.9

›Positive beta-hCG with free pelvic fluid

›Ovarian or testicular torsion

›ICD-10 N83.5

›Acute onset with 6-hour viability window

Common diagnoses by region

›Right upper quadrant

›Biliary colic and cholecystitis

›ICD-10 K80.20

›Postprandial RUQ pain with positive Murphy sign

›Ascending cholangitis

05Laboratory Tests/lt37

Core diagnostic labs

›Hematology and infection markers

›Complete blood count

›Leukocytosis supporting inflammation or infection

›Hemoglobin drop suggesting hemorrhage

›C-reactive protein

›Adjunct for inflammatory pathology

›Limited specificity alone

›Metabolic and organ panels

›Electrolytes and renal function

›Baseline before contrast imaging

›Acid-base disturbance clues

›Liver function tests

›Elevated in biliary obstruction and hepatitis

›Bilirubin in cholangitis

›Lipase

›Greater than 3x upper limit supports pancreatitis

›More specific than amylase

Perfusion and bedside tests

›Lactate

›>= 2 mmol/l as hypoperfusion marker

›Marked elevation in mesenteric ischemia

›Serial trend to assess resuscitation

›Point-of-care pregnancy test

›Urine or serum beta-hCG in all reproductive-age patients

›Mandatory before imaging and disposition

›Urinalysis

›Hematuria in urolithiasis

06Diagnostic Tests/dt71

Scoring Systems

›Appendicitis stratification

›Alvarado score

›Migratory pain and anorexia and nausea

›Tenderness and rebound in RLQ

›Fever and leukocytosis and left shift

›Score <= 4 low probability

›Score >= 7 high probability favoring imaging or surgery

›Adult Appendicitis Score

›Incorporates CRP and neutrophil values

›Reduces unnecessary CT in low-risk patients

›Severity and bleeding tools

›Glasgow-Blatchford score

›Upper GI bleed risk stratification

›Score 0 supports outpatient management

›qSOFA for sepsis screening

›RR >= 22 per minute

›SBP <= 100 mmHg

›Altered mental status

›Limitations

›Scores adjunctive to clinical judgment

›Trajectory supersedes single score

›ACEP Level C recommendation for adjunct use

MRI

›MRI abdomen and pelvis indications

›Pregnancy with suspected appendicitis

›After equivocal ultrasound

›No ionizing radiation

07Disposition/dispo31

Admission and escalation

›Admission indications

›Surgical pathology

›Appendicitis and obstruction

›Perforation and ischemia

›Intractable symptoms

›Uncontrolled pain

›Persistent vomiting and dehydration

›Diagnostic uncertainty in high-risk patient

›Elderly with concerning trajectory

›Immunocompromised host

›ICU and operative escalation

›Hemodynamic instability

›Vasopressor requirement

›Rising lactate despite resuscitation

›Emergent operative need

›Ruptured AAA to operating room

›Peritonitis with sepsis

Discharge and follow-up

›Safe discharge criteria

›Hemodynamic stability

›Normal serial vitals

›Tolerating oral intake

›Benign serial abdominal exam

›Pain controlled with oral analgesia

›No peritoneal signs

›Reassuring workup

›Negative or reassuring imaging

08Treatment/t66

Resuscitation and supportive care

›Initial stabilization

›IV access and fluids

›Balanced crystalloid for hypoperfusion

›Blood products for hemorrhagic shock

›NPO status

›If surgical pathology suspected

›If contrast imaging planned

›Nasogastric decompression

›Bowel obstruction with vomiting

›Reduces aspiration risk

Analgesia

›Early analgesia principles

›Analgesia safe and does not reduce diagnostic accuracy

›Do not withhold pending surgical evaluation

›ACEP Level B recommendation

›Non-opioid first-line

›IV acetaminophen

›1 g IV every 6 hours

›Maximum 4 g per day

›Ketorolac

›15 to 30 mg IV

›Avoid in suspected GI bleed and renal insufficiency

›Opioids

›Morphine

›0.05 to 0.1 mg/kg IV titrated

›Repeat every 10 to 15 minutes to effect

›Hydromorphone

09Special Populations/sp62

Pregnancy

›Diagnostic approach

›Ultrasound and MRI preferred

›Avoid ionizing radiation when feasible

›MRI for equivocal appendicitis

›Anatomic shift

›Appendix displaced upward in late pregnancy

›Atypical pain location

›Cannot-miss obstetric causes

›Ectopic pregnancy

›Beta-hCG and transvaginal ultrasound

›Free fluid with shock

›Placental abruption and preeclampsia

›Third-trimester pain with bleeding

›HELLP with RUQ pain

›Medication safety

›Acetaminophen first-line analgesic

›Avoid NSAIDs in third trimester

›Antibiotic selection

›Beta-lactams preferred

›Avoid fluoroquinolones and tetracyclines

Geriatric

›Atypical presentation

›Blunted findings

›Afebrile despite serious pathology

›Minimal tenderness in perforation

›Higher morbidity and mortality

›Delayed diagnosis common

10Background/b48

Epidemiology

›Burden of disease

›Frequency

›5% to 10% of all ED visits

›Over 150 possible etiologies

›Most common diagnoses

›Gastroenteritis 10.8%

›Nonspecific abdominal pain 10.4%

›Outcomes

›Surgical need

›15% to 20% require interventional or surgical treatment

›Mortality

›Ranges 2% to 12%

›Rises with each hour of delay to definitive treatment

Pathophysiology

›Pain mechanisms

›Visceral pain

›Poorly localized and midline

›Stretch and ischemia of hollow organs

›Somatic pain

›Localized and sharp

›Parietal peritoneum irritation

›Referred pain

›Shared spinal segments

›Diaphragmatic irritation to shoulder

›Disease mechanisms

›Obstruction and distension

›Luminal blockage and proximal dilation

11Patient Discharge Instructions/pdi21

copy discharge instructions

›Home care guidance

›Clear liquids advancing to bland diet as tolerated

›Rest and stay hydrated

›Take prescribed medications as directed

›Avoid alcohol and NSAIDs unless approved

›Warning signs to return to ER

›Worsening or constant severe pain

›Pain moving to the right lower belly

›Persistent vomiting or inability to keep fluids down

›Fever or chills

›Blood in vomit or stool or black stools

›Fainting or dizziness

›Yellowing of skin or eyes

›Swollen rigid or very tender belly

›Follow-up plan

›Primary care or surgical follow-up within 1 to 3 days

›Return sooner if symptoms worsen

›Bring this paperwork to follow-up visits

›Reproductive-age guidance

›Seek care for missed period with pelvic pain

›Pregnancy test if pregnancy possible

12References/r12

Guidelines and key sources

›Primary references

›AAFP acute abdominal pain in adults evaluation and diagnosis 2023

›NEJM acute abdomen in the modern era 2024

›Deutsches Arzteblatt structured diagnosis of the acute abdomen 2025

›Specialty guidelines

›WSES acute mesenteric ischemia guidelines 2022

›ACEP optimizing treatment of acute pain in the ED 2018

›ACS gastrointestinal surgical emergencies textbook 2021

›Evidence and coding standards

›DREAMER trial droperidol for abdominal pain 2025

›Cochrane review prophylactic antiemetics with IV opioids 2022

›ICD-10 R10 abdominal and pelvic pain

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Reviewed by SymptomDx Medical Team · Last reviewed August 18, 2026

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