The Daily Differential — Wednesday, April 22, 2026

2 of 5

Biliary Disease

Biliary colic, cholecystitis, and cholangitis are common ED abdominal pain diagnoses, but cholangitis and complicated cholecystitis can deteriorate quickly....

At the Bedside

Biliary colic: episodic RUQ/epigastric pain after fatty meals, often afebrile with normal labs; ultrasound shows gallstones without inflammatory signs.
Acute cholecystitis: persistent RUQ pain, fever, nausea/vomiting, Murphy sign, leukocytosis; ultrasound findings include gallstones, wall thickening, pericholecystic fluid, sonographic Murphy sign.
Cholangitis: fever, jaundice, RUQ pain; may progress to hypotension/AMS (Reynolds pentad). This is an emergency requiring antibiotics, resuscitation, and biliary decompression.
Labs: CBC, CMP, bilirubin, AST/ALT, alkaline phosphatase, lipase. Marked cholestatic pattern suggests ductal obstruction; elevated lipase raises gallstone pancreatitis concern.
Imaging: RUQ ultrasound first-line. If equivocal and suspicion remains, consider HIDA for cholecystitis or MRCP/ERCP pathway depending on suspected ductal disease and local resources.
Initial ED treatment: IV fluids if dehydrated/septic, analgesia, antiemetics, NPO if intervention likely.
Antibiotics: indicated for cholecystitis with systemic features, all cholangitis, and complicated biliary infection.
Disposition: uncomplicated biliary colic can sometimes discharge with surgery follow-up if pain controlled and no red flags; cholecystitis usually admit/surgery; cholangitis admit, broad antibiotics, and urgent GI/surgery for drainage.

Classic Presentation

A 44-year-old woman has constant RUQ pain, fever, and vomiting after a fatty meal. She is tender in the RUQ with a positive Murphy sign and mild jaundice. Ultrasound shows gallstones, gallbladder wall thickening, and a dilated common bile duct. The ED gives fluids, pain control, and broad antibiotics, then consults GI for urgent ERCP and surgery for admission.

Study Directive

Memorize the ultrasound findings that distinguish biliary colic vs cholecystitis.
Practice writing an ED order set for cholangitis.
Draw the decision pathway: RUQ pain + fever + jaundice → antibiotics + consult for drainage.
Review common biliary lab patterns: cholestatic vs hepatocellular.
Do 5 questions on when to call GI vs surgery.

Key Medications

Ketorolac: 15 mg IV; may use 30 mg IV/IM in selected adults, but 15 mg IV is common and safer in many EDs.
Morphine: 2–4 mg IV titrated, or hydromorphone 0.2–1 mg IV titrated.
Ondansetron: 4–8 mg IV/PO.
Ceftriaxone: 1–2 g IV daily for biliary infection depending on severity/local protocol.
Metronidazole: 500 mg IV every 8 hours when anaerobic coverage is needed.
Piperacillin-tazobactam: 4.5 g IV every 6 hours for severe infection/sepsis if chosen by local antibiogram.
Pediatric note: gallstones are less common; dosing must be weight-based and pediatric surgery input is important.

High-Yield Pearls

Charcot triad = fever, jaundice, RUQ pain; think cholangitis.
Ultrasound is excellent for gallstones and cholecystitis, but a normal ultrasound does not fully exclude biliary disease.
Gallstone pancreatitis can present with elevated lipase and biliary labs; treat as biliary obstruction until proven otherwise.

Board Question

A patient with RUQ pain, fever, jaundice, and hypotension is most likely to need which next step?

ADischarge with low-fat diet advice
BOral antibiotics and outpatient ultrasound
CBroad-spectrum IV antibiotics and urgent biliary decompression
DObservation only

Reveal answer

Correct: C

Broad-spectrum IV antibiotics and urgent biliary decompression. This is ascending cholangitis until proven otherwise. Antibiotics are necessary, but source control via ERCP or other decompression is definitive and should not be delayed.

3 of 5

Cannabis Hyperemesis Syndrome

CHS causes repeated ED visits, dehydration, and unnecessary workups if not recognized. The key treatment is symptom control plus cannabis cessation...

At the Bedside

Classic story: chronic heavy cannabis use, recurrent severe vomiting, abdominal pain, and relief with hot showers/baths.
Workup: rule out dangerous mimics based on symptoms and exam. Consider pregnancy test, electrolytes, renal function, lipase, urinalysis, and imaging only if concerning features suggest alternate pathology.
Exam: often benign abdominal exam or mild diffuse tenderness; dehydration is common.
Initial management: IV fluids, correct hypokalemia, treat nausea, consider capsaicin or dopamine antagonists.
Avoid anchoring: CHS is a diagnosis of pattern recognition after excluding other causes of vomiting, especially in first presentations.
Disposition: discharge when symptoms controlled, able to tolerate PO, and counseling provided; admit if refractory vomiting, AKI, significant electrolyte derangements, or alternative diagnosis suspected.

Classic Presentation

A 26-year-old man presents for the fourth time this month with nonstop vomiting and crampy abdominal pain. He reports daily marijuana use and says hot showers are the only thing that helps. Vitals show mild tachycardia; exam is nonfocal. Labs show hypokalemia and mild AKI. After IV fluids, haloperidol, and topical capsaicin, his vomiting improves and he is discharged with strict cannabis cessation counseling.

Study Directive

Make a one-page differential for recurrent vomiting with columns for CHS, cyclical vomiting, gastroparesis, pregnancy, and obstruction.
Memorize one CHS treatment sequence from your ED: fluids → electrolyte correction → dopamine antagonist → capsaicin.
Practice documenting a clear cannabis cessation counseling note.
Review QTc precautions for haloperidol/droperidol.
Teach a co-resident the hot shower clue from memory.

Key Medications

Haloperidol: 0.05 mg/kg IV/IM commonly used for CHS; adult dosing often 2.5–5 mg IV/IM. Monitor QTc and extrapyramidal effects.
Droperidol: 0.625–2.5 mg IV/IM often effective; QT considerations apply per local policy.
Ondansetron: 4–8 mg IV/PO, though response may be limited.
Metoclopramide: 10 mg IV may be tried.
Topical capsaicin: 0.025%–0.1% cream applied to abdomen/arms per local protocol; wash hands and warn about burning sensation.
Lorazepam: 0.5–2 mg IV/PO may help selected patients with anxiety/nausea; use cautiously.
Pediatric note: CHS is increasingly recognized in adolescents; dosing and differential should be age-appropriate.

High-Yield Pearls

Hot showers are a clue, not a requirement.
Haloperidol and droperidol often work better than ondansetron.
Definitive treatment is cannabis cessation; without it, relapse is common.

Board Question

Which historical feature is most suggestive of cannabis hyperemesis syndrome?

APain worsened by eating greasy foods
BRelief with hot showers
CProgressive dysphagia
DBilious vomiting in infancy

Reveal answer

Correct: B

Relief with hot showers. Compulsive hot bathing is a classic clue for CHS. The syndrome is strongly associated with chronic cannabis use and recurrent vomiting that is often refractory to standard antiemetics.

4 of 5

Cyclical Vomiting

Cyclical vomiting syndrome causes recurrent, stereotyped vomiting episodes that can mimic toxic, metabolic, or surgical disease. ED care focuses on...

At the Bedside

Pattern: recurrent discrete episodes of intense vomiting separated by symptom-free intervals; often associated with migraine history, stress, sleep deprivation, or triggers.
Diagnosis is one of exclusion: rule out pregnancy, obstruction, DKA, intracranial pathology when indicated, pancreatitis, infection, and substance-related vomiting.
Workup: electrolytes, glucose, renal function, pregnancy test when applicable, urinalysis, lipase if pain suggests it; image based on exam/red flags.
Treatment: IV fluids, antiemetics, consider migraine-directed therapy if phenotype fits, and address dehydration/electrolyte losses.
Disposition: discharge if improved and tolerating PO; admit if refractory symptoms, AKI, severe metabolic derangement, or inability to exclude another diagnosis.

Classic Presentation

A 32-year-old woman with a migraine history presents with her third identical vomiting episode this year. She has no abdominal tenderness, no fever, and normal imaging from prior visits. Current labs show mild hypokalemia and dehydration. She improves with IV fluids, ondansetron, and a migraine-oriented antiemetic regimen, then is discharged with outpatient GI/primary care follow-up.

Study Directive

Compare CVS vs CHS in a two-column memory sheet.
Practice your “recurrent vomiting” workup algorithm.
Identify red flags that force imaging or admission.
Review migraine-associated antiemetic strategies.
Write a sample discharge plan including trigger avoidance and follow-up.

Key Medications

Ondansetron: 4–8 mg IV/PO.
Metoclopramide: 10 mg IV.
Prochlorperazine: 10 mg IV/IM.
Diphenhydramine: 25–50 mg IV/PO, often used to reduce dystonia with dopamine antagonists.
Ketorolac: 15 mg IV if migraine-like features and renal function permit.
Lorazepam: 0.5–2 mg IV/PO in selected patients, especially with anxiety or anticipatory nausea.
Pediatric note: cyclical vomiting is more common in children; pediatric migraine association is strong and dosing is weight-based.

High-Yield Pearls

CVS is episodic with symptom-free intervals; CHS usually needs cannabis exposure history.
Don’t diagnose CVS until you’ve considered pregnancy, obstruction, DKA, and toxicologic causes.
Recurrent dehydration can cause hypokalemia and metabolic alkalosis.

Board Question

Which associated condition is most classically linked to cyclical vomiting syndrome?

AMigraine
BUlcerative colitis
CHemochromatosis
DMyasthenia gravis

Reveal answer

Correct: A

Migraine. Cyclical vomiting syndrome is often associated with migraine biology and stereotyped recurrent episodes. The ED priority is supportive care and exclusion of emergent mimics.

5 of 5

Esophageal Foreign Bodies

Esophageal obstruction can cause airway compromise, aspiration, perforation, and mucosal injury. Timing matters: complete obstruction or sharp/battery...

At the Bedside

Assess airway first: drooling, inability to swallow secretions, stridor, respiratory distress, or altered mental status may require emergent airway management and endoscopy.
History: time of ingestion, object type, dentures, food bolus, prior esophageal disease/stricture, psychiatric or intentional ingestion risk.
Physical exam: inspect for distress, drooling, neck crepitus, chest pain, focal tenderness, and signs of perforation.
Imaging: neck/chest radiographs for radiopaque objects, button batteries, coins, or suspected perforation. CT if object is radiolucent, complications suspected, or location unclear.
Urgency:
Emergent endoscopy: complete obstruction, sharp objects, button batteries in esophagus, magnets, perforation concern.
Urgent endoscopy: esophageal food bolus or foreign body not passing.
Avoid blind sweeping of the oropharynx if object not visualized.
Disposition: most esophageal foreign bodies need GI/ENT removal; discharge only after confirmed passage or safe removal with symptom resolution.

Classic Presentation

A 71-year-old man with dentures presents after eating steak and now cannot swallow saliva. He is drooling and reports retrosternal discomfort but no dyspnea. Neck x-ray is unrevealing, and he remains unable to handle secretions. GI is called for urgent endoscopic removal of an esophageal food bolus.

Study Directive

Memorize the emergent vs urgent foreign body categories.
Practice reading x-rays for coin vs button battery.
Review your local pathway for GI vs ENT involvement.
Write the first-line ED steps for a patient drooling after food impaction.
Know which symptoms suggest perforation and mandate CT/surgical consult.

Mechanism Pearl of the Day: Several of today’s topics center on obstruction plus secondary injury: variceal or biliary obstruction causes upstream pressure and bleeding/infection, CHS/CVS cause repeated emesis with volume and electrolyte loss, and esophageal foreign bodies cause direct mucosal injury and aspiration risk. In the ED, the mechanism-based question is often: Is this a simple symptom syndrome, or is there a blocked duct/tube that needs source control or removal?

Key Medications

Glucagon: 1 mg IV once for presumed food bolus may be attempted, though efficacy is limited and variable. Check local practice.
Ondansetron: 4–8 mg IV/PO.
Topical or nebulized lidocaine: practice varies; if used, dosing and airway risk should be checked carefully.
Sedation for endoscopy: per procedural sedation protocol.
Pediatric note: button batteries in the esophagus are a true emergency; remove immediately.

High-Yield Pearls

Inability to handle secretions = high-risk obstruction.
Coins and batteries can look similar on x-ray; batteries may show a “double rim” or halo sign.
Sharp objects and button batteries are more urgent than blunt objects.

Board Question

Which esophageal foreign body requires the most urgent removal?

ASmall coin in the stomach
BButton battery lodged in the esophagus
CPlastic spoon in the colon
DSmooth pebble in the stomach

Reveal answer

Correct: B

Button battery lodged in the esophagus. Button batteries can cause rapid liquefactive necrosis and perforation within hours. Esophageal location makes this an emergency requiring immediate removal.

TheDaily Differential

Approach to Gastrointestinal Bleeding

At the Bedside

Study Directive

More in Today's Issue

Biliary Disease

At the Bedside

Study Directive

Key Medications

High-Yield Pearls

Cannabis Hyperemesis Syndrome

At the Bedside

Study Directive

Key Medications

High-Yield Pearls

Cyclical Vomiting

At the Bedside

Study Directive

Key Medications

High-Yield Pearls

Esophageal Foreign Bodies

At the Bedside

Study Directive

Key Medications

High-Yield Pearls

Journal Watch

Clinical Conundrum: What Is the Role of TXA in Dysfunctional Uterine Bleeding?

Podcast Pick

EMCrit 423 – Hyperbaric Therapy for Carbon Monoxide Poisoning?

Case of the Day