The Daily Differential — Sunday, April 26, 2026

2 of 5

Singultus (Hiccups)

Hiccups are usually benign, but persistent (>48 hours) or intractable (>1 month) singultus can signal serious pathology: CNS lesions, diaphragmatic...

At the Bedside

Pathophysiology:
Reflex arc involving afferents (vagus, phrenic, sympathetic chain), central mediator (brainstem), and efferent diaphragm/intercostals with glottic closure.
History:
Duration, frequency, sleep interruption, inability to eat/drink.
Chest pain, dyspnea, cough, fever.
Headache, focal deficits, vertigo, dysarthria.
Reflux, abdominal pain, distention, vomiting.
Alcohol use, recent surgery/endoscopy.
Cancer history, renal failure, diabetes.
Meds: steroids, benzodiazepines, dopamine agonists, chemotherapy, opioids.
Exam:
Full vitals.
HEENT for pharyngeal irritation/foreign body.
Chest exam for pneumonia, effusion, pericardial process.
Abdominal exam for hepatomegaly, obstruction, peritonitis.
Neuro exam, especially posterior circulation findings.
Initial workup when persistent, ill-appearing, or secondary cause suspected:
ECG if chest symptoms.
CXR for thoracic causes.
BMP/CMP: sodium, calcium, renal function, glucose, LFTs.
CBC if infection/malignancy concern.
Troponin if ACS concern.
CT head/brain imaging if focal neuro findings, persistent unexplained hiccups with neuro symptoms, concern for stroke/mass.
CT chest/abdomen selectively for malignancy, obstruction, PE, abscess, diaphragmatic irritation.
Bedside maneuvers for acute benign hiccups:
Breath holding, Valsalva, sipping cold water, swallowing granulated sugar, vagal maneuvers.
These are reasonable only in well-appearing patients without concerning features.
Symptomatic treatment:
Treat the cause: GERD therapy, pneumonia treatment, electrolyte correction, relieve gastric distention, etc.
Persistent bothersome hiccups:
Metoclopramide, chlorpromazine, baclofen, gabapentin are common options.
Disposition:
Discharge if benign/short-lived and secondary dangerous causes are not suspected.
Admit or urgent specialty evaluation if inability to tolerate PO, severe sleep deprivation/exhaustion, significant metabolic derangement, pneumonia/ACS/CNS lesion/obstruction, or unexplained persistent hiccups in a high-risk patient.

A Classic Presentation

A 67-year-old man presents with 3 days of persistent hiccups, poor sleep, and new imbalance. He denies abdominal pain but has mild nausea and difficulty walking. Vitals are normal. Exam shows subtle limb ataxia and direction-changing nystagmus. CXR is unrevealing, labs are normal, and MRI demonstrates a lateral medullary infarct. He receives symptomatic hiccup therapy, is admitted for stroke management, and the singultus is recognized as a posterior circulation warning sign rather than a benign nuisance complaint.

Study Directive

Memorize the hiccup reflex arc: vagus/phrenic afferents → brainstem → diaphragm/glottis.
Make a differential by anatomic bucket: CNS, thoracic, GI/diaphragm, metabolic, medication-induced.
Review 5 “can’t-miss” causes: stroke, MI/ACS, pneumonia, PE, bowel obstruction.
Create a symptom-triggered workup card: when hiccups need CXR, electrolytes, ECG/troponin, and neuroimaging.
On your next shift, ask yourself with every “benign” complaint: what historical clue would make this dangerous?

Key Medications

Metoclopramide
10 mg IV or PO
Useful if associated with reflux/gastric distention.
Chlorpromazine
25 mg PO/IV/IM
If IV, give diluted/slowly and monitor for hypotension; practice varies, so check local protocol/reference.
Baclofen
5–10 mg PO
More common for persistent outpatient management than immediate ED effect.
Gabapentin
100–300 mg PO
Dosing varies meaningfully by indication and renal function; check a reference if starting.
Pantoprazole
40 mg PO/IV if reflux suspected.
Famotidine
20 mg IV/PO as adjunct in reflux-related symptoms.

High-Yield Pearls

Intractable hiccups can be a brainstem lesion until proven otherwise when paired with vertigo, ataxia, dysphagia, or cranial nerve findings.
Thoracic and subdiaphragmatic irritation are common secondary drivers: pneumonia, PE, mediastinal disease, liver pathology, gastric distention.
Chlorpromazine is classic board-answer therapy, but many EDs use metoclopramide first because it is more familiar and often better tolerated.

Board Question

A 58-year-old man presents with persistent hiccups for 72 hours and new vomiting, gait instability, and hoarse voice. Which diagnosis should be most strongly considered?

AGERD
BLateral medullary stroke
CPanic attack
DViral pharyngitis Correct answer:
BExplanation: Persistent hiccups plus posterior circulation symptoms should prompt concern for brainstem pathology, especially lateral medullary infarction. The hiccup reflex arc has a central brainstem component.

3 of 5

Thoracostomy

Tube thoracostomy is lifesaving for pneumothorax, hemothorax, and some pleural infections. Mistakes in indication, placement site, sterile technique, or...

At the Bedside

Indications:
Traumatic pneumothorax needing drainage
Hemothorax/hemopneumothorax
Tension pneumothorax after immediate needle/finger decompression
Large or symptomatic spontaneous pneumothorax
Ventilated patient with pneumothorax
Selected empyema/complicated pleural effusion (often pigtail depending on context)
Contraindications:
No absolute contraindication in life-threatening thoracic pathology.
Relative: coagulopathy, pleural adhesions, prior surgery, uncertainty of anatomy.
Tube choice:
Traditional trauma teaching favored large-bore for blood; many centers now use smaller tubes or pigtails for uncomplicated PTX and selected traumatic hemothorax.
Follow institutional/trauma protocol.
Landmarks:
“Safe triangle”: lateral border of pectoralis major, anterior border of latissimus dorsi, line superior to nipple/5th intercostal space, apex below axilla.
Insert just over the rib to avoid neurovascular bundle.
Procedure:
Consent if possible; monitor patient; analgesia/sedation as appropriate.
Prep and drape widely.
Local anesthesia: skin, periosteum of rib, pleura.
Incision over 4th–5th intercostal space anterior/mid-axillary line.
Blunt dissection with clamp through subcutaneous tissue and intercostal muscles into pleura.
Finger thoracostomy/finger sweep confirms pleural entry and clears adhesions.
Direct tube posterior/apical for pneumothorax; posterior/basal for blood/fluid.
Connect to drainage system, secure tube, occlusive dressing.
Post-placement:
Immediate assessment: improvement in vitals/respiratory distress, bubbling, tidaling, blood output.
CXR to confirm position unless proceeding directly to OR/CT and patient is stable.
Continuous suction vs water seal depends on indication and protocol.
Massive hemothorax / operative triggers:
Initial output >1500 mL or ongoing output >200 mL/hr for 2–4 hr are classic thresholds suggesting operative intervention; use clinical context.
Complications:
Malposition, subcutaneous placement, organ injury (lung, diaphragm, liver, spleen), intercostal vessel injury, infection, re-expansion pulmonary edema, persistent air leak.
Disposition:
Most patients with chest tubes are admitted.
Trauma patients often need trauma surgery admission.
Some small spontaneous PTX with pigtail/one-way valve may be discharged under protocol.

A Classic Presentation

A 32-year-old man presents after a stab wound to the left chest with dyspnea and decreased breath sounds. He is tachycardic but normotensive. Ultrasound shows absent lung sliding and CXR confirms a large left pneumothorax. After analgesia, sterile prep, and local anesthesia, a tube thoracostomy is placed in the 5th intercostal space anterior to the mid-axillary line using blunt dissection and finger confirmation. Air rushes out, respiratory distress improves, post-procedure film confirms position, and he is admitted to trauma surgery.

Study Directive

Draw the safe triangle from memory and identify nearby structures you must avoid.
Rehearse the procedure verbally in order: anesthesia, incision, blunt dissection, pleural entry, finger sweep, tube direction, securement, post-check.
Memorize operative hemothorax thresholds and know your trauma service’s pigtail vs large-bore preferences.
Review 10 post-tube CXRs and decide if the tube is intrathoracic, directed appropriately, kinked, or too deep.
Practice lidocaine maximum dose calculations on 3 sample patient weights.

Key Medications

Lidocaine 1% or 2%*
Local infiltration; common maximum without epi about 4.5 mg/kg, with epi about 7 mg/kg.
Check total dose carefully, especially in smaller patients.
Fentanyl
25–100 mcg IV titrated for analgesia.
Ketamine
Analgesic dose: 0.1–0.3 mg/kg IV
Procedural dissociation: 1–2 mg/kg IV if needed.
Midazolam
1–2 mg IV in small titrated doses if anxiolysis needed; caution with respiratory compromise.
Propofol
0.5–1 mg/kg IV then titrate if full procedural sedation required in a stable patient.
Cefazolin
2 g IV (3 g if weight-based institutional threshold, commonly >120 kg)
Prophylactic antibiotics in traumatic chest tubes vary by service/protocol; check local guidance.
Ondansetron
4 mg IV if nausea expected with opioids/sedation.

High-Yield Pearls

Finger thoracostomy after blunt dissection confirms pleural entry and reduces the chance of placing a tube into soft tissue.
Large initial hemothorax output or persistent high output suggests major vascular injury and need for operative evaluation, not just a bigger tube.
Small-bore pigtails are increasingly used for selected pneumothoraces and even some hemothoraces, but unstable trauma still demands straightforward, protocol-driven management.

Board Question

For standard tube thoracostomy, the preferred insertion site is:

A2nd intercostal space, midclavicular line
B5th intercostal space, anterior or mid-axillary line within the safe triangle
C8th intercostal space, posterior axillary line
DDirectly over the inferior edge of the rib Correct answer:
BExplanation: Standard chest tubes are typically placed in the 4th–5th intercostal space in the safe triangle. The tube should pass just over the superior rib margin to avoid the intercostal neurovascular bundle on the inferior rib border.

4 of 5

Thoracotomy

Resuscitative thoracotomy is one of the highest-stakes procedures in emergency medicine. It is rarely indicated, but when appropriately performed in the...

At the Bedside

Typical ED indication:
Traumatic arrest or peri-arrest, especially penetrating thoracic trauma, with signs of life and very short/no-flow time.
Strongest scenarios:
Penetrating chest trauma with loss of pulses in ED or immediately prior, especially with suspected tamponade.
Selected penetrating extrathoracic trauma with brief downtime.
Selected blunt trauma only in extremely narrow circumstances and usually with witnessed arrest and very short downtime; outcomes are poor.
“Signs of life” may include:
Pupillary response, spontaneous movement, organized ECG activity, measurable blood pressure, respiratory effort.
Goals of procedure:
Release pericardial tamponade
Control cardiac wound temporarily
Internal cardiac massage
Descending thoracic aortic cross-clamp to redistribute flow to heart/brain and limit below-diaphragm hemorrhage
Control hilar/major intrathoracic bleeding in select cases
Simultaneous resuscitation:
Massive transfusion
Airway/oxygenation
Bilateral chest decompression as indicated
Correct reversible causes
Procedure overview:
Usually left anterolateral thoracotomy in 4th–5th intercostal space from sternum toward posterior axillary line.
Open chest, rib spreader.
Identify pericardium and open anterior to phrenic nerve.
Evacuate blood/clot; relieve tamponade.
Control myocardial wound with finger, skin stapler, Foley balloon, or suturing by trained operators.
Internal cardiac massage if indicated.
Cross-clamp descending thoracic aorta if profound shock/arrest from subdiaphragmatic bleeding.
Extend to clamshell if bilateral access required.
Contraindications / futility concerns:
Prolonged pulselessness without signs of life
Blunt trauma with prolonged CPR and no signs of life
Nontraumatic arrest in most cases
Obviously unsurvivable injuries
Exact time cutoffs vary by system/protocol; use institutional and trauma guidance.
Disposition:
If ROSC/meaningful perfusion achieved, immediate OR/trauma surgery.
If no salvageable physiology, termination per protocol.

A Classic Presentation

A 24-year-old man with a stab wound to the precordium arrives pulseless after losing pulses 2 minutes before ED arrival. Monitor shows organized electrical activity. FAST shows pericardial effusion. Massive transfusion is initiated and a left anterolateral thoracotomy is performed. The pericardium is opened anterior to the phrenic nerve, clot is evacuated, a right ventricular laceration is digitally occluded, and perfusing rhythm returns. He is taken emergently to the OR.

Study Directive

Memorize candidacy buckets: penetrating chest, penetrating non-chest, blunt trauma, and what “signs of life” means.
Review your institution’s trauma thoracotomy policy and prehospital downtime thresholds.
Practice the verbal sequence of left anterolateral thoracotomy and pericardiotomy on a diagram.
Learn 3 temporary cardiac wound control methods: finger pressure, skin stapler, Foley balloon.
During trauma activations, deliberately identify who is and is not a thoracotomy candidate.

Key Medications

There are no signature “thoracotomy drugs”; this is a procedural and hemorrhagic resuscitation event.
Blood products
Activate massive transfusion protocol; balanced product resuscitation per institutional protocol.
TXA
1 g IV over 10 min, then 1 g over 8 hr in selected trauma patients within 3 hr of injury.
Follow institutional trauma criteria.
Calcium chloride
1 g IV during massive transfusion as indicated.
Epinephrine
Standard ACLS dosing may be used in traumatic arrest, but definitive hemorrhage/tamponade control matters more than repeated vasopressors.
Analgesia/sedation
Usually irrelevant in true arrest/peri-arrest; if peri-arrest but conscious, management is highly situation-dependent and should follow trauma/surgical leadership.

High-Yield Pearls

The board-favorite best indication is penetrating chest trauma + recent arrest + suspected tamponade.
Open the pericardium anterior to the phrenic nerve to avoid injuring it.
Aortic cross-clamping is for temporary redistribution of blood flow and control of distal exsanguination; it is not definitive hemorrhage control.

Board Question

Which trauma patient has the highest likelihood of benefit from ED resuscitative thoracotomy?

ABlunt trauma arrest with 20 minutes of prehospital CPR and no signs of life
BPenetrating precordial stab wound with loss of pulses on ED arrival and pericardial tamponade
CAsystolic medical cardiac arrest with no trauma
DPenetrating abdominal trauma with 30 minutes of pulselessness and fixed pupils Correct answer:
BExplanation: Resuscitative thoracotomy has its best outcomes in penetrating thoracic trauma with very recent loss of signs of life, especially when tamponade is present. Prolonged pulselessness and blunt trauma are much lower-yield scenarios.

5 of 5

Central Nervous System Infections

CNS infections are time-critical, high-morbidity emergencies. Missing bacterial meningitis, HSV encephalitis, ventriculitis, epidural abscess, or brain...

At the Bedside

Core syndromes:
Meningitis: meningeal inflammation; fever, headache, neck stiffness, photophobia, altered mental status.
Encephalitis: brain parenchymal inflammation; altered mentation, seizures, focal deficits, behavioral changes.
Brain abscess: focal deficits, headache, seizure, signs of mass effect.
Spinal epidural abscess: back pain, fever, neuro deficits; not intracranial but often board-linked.
Immediate priorities:
Sepsis resuscitation if unstable.
Treat seizures, correct hypoxia/hypoglycemia.
Start empiric antimicrobials early when bacterial meningitis or HSV encephalitis is suspected.
Do not delay antibiotics unnecessarily for LP or imaging.
History:
Immunocompromise, HIV, transplant, cancer, steroids.
VP shunt/neurosurgery.
Recent sinusitis/otitis/mastoiditis.
Rash, sick contacts, travel, tick exposure.
IVDU, endocarditis.
Age extremes.
Exam:
Full neuro exam.
Mental status.
Meningismus may be absent, especially elderly/immunocompromised.
Rash/petechiae (meningococcemia).
Papilledema, focal deficits, cranial nerve deficits.
Diagnostic workup:
Blood cultures x2 before antibiotics if this does not cause major delay.
CBC, CMP, lactate as needed.
Coags if LP planned or coagulopathy suspected.
Pregnancy test when relevant.
CT head before LP if any of the following:
Immunocompromised
New seizure
Papilledema
Focal neurologic deficit
Altered level of consciousness
History of CNS lesion
LP when safe:
Opening pressure
Cell count/differential
Protein
Glucose (compare with serum)
Gram stain/culture
HSV PCR when encephalitis suspected
Additional tests by scenario: cryptococcal antigen, VDRL, fungal/AFB studies, enterovirus PCR, etc.
Typical CSF patterns:
Bacterial: high WBC with neutrophilic predominance, high protein, low glucose.
Viral: lymphocytic predominance, normal/mildly high protein, normal glucose.
Fungal/TB: lymphocytes, high protein, low glucose.
Early disease can blur patterns.
Empiric treatment principles:
Suspected community-acquired bacterial meningitis:
Dexamethasone first or with first antibiotic dose.
Ceftriaxone + vancomycin.
Add ampicillin if age >50, immunocompromised, alcoholism, or pregnancy for Listeria coverage.
Suspected encephalitis:
Add acyclovir.
Neurosurgical/shunt-associated meningitis:
Vancomycin + antipseudomonal beta-lactam (e.g., cefepime or meropenem).
Brain abscess:
Broad therapy based on source, often ceftriaxone + metronidazole ± vancomycin; consult neurosurgery.
Special entities:
HSV encephalitis: temporal lobe involvement, personality change, seizures; give acyclovir early.
Meningococcemia: purpuric rash, shock, DIC; droplet precautions and aggressive sepsis care.
Cryptococcal meningitis: immunocompromised, elevated opening pressure; management requires antifungals and often serial pressure control.
Brain abscess: avoid LP if mass lesion suspected due to herniation risk.
Disposition:
Bacterial meningitis/encephalitis: ICU or monitored admission.
Brain abscess, ventriculitis, shunt infection: specialty-guided admission, often ICU.
Never discharge a patient with unresolved concern for acute CNS infection.

A Classic Presentation

A 41-year-old woman presents with fever, severe headache, vomiting, and progressive confusion over 8 hours. She is febrile, tachycardic, photophobic, and intermittently follows commands. No focal deficit is seen, but she is clearly altered. Blood cultures are drawn, dexamethasone is given, and empiric ceftriaxone, vancomycin, ampicillin, and acyclovir are started immediately. CT head is obtained before LP because of altered mental status, then LP shows elevated opening pressure, neutrophilic pleocytosis, high protein, and low glucose, confirming bacterial meningitis. She is admitted to the ICU.

Study Directive

Memorize the adult empiric meningitis regimen by age/risk: standard vs older/immunocompromised vs neurosurgical/shunt-associated.
Practice the CT-before-LP criteria from memory until automatic.
Build a one-line CSF interpretation rule for bacterial, viral, and fungal/TB meningitis.
Review HSV encephalitis clues: temporal lobe symptoms, seizures, behavioral change, RBCs in CSF can occur.
Complete 10 board-style questions distinguishing meningitis, encephalitis, brain abscess, and spinal epidural abscess.

---

Mechanism Pearl of the Day: Several of today’s topics hinge on pressure physiology: sedatives can depress ventilation and raise CO2; thoracostomy/thoracotomy relieve life-threatening intrathoracic pressure or tamponade; CNS infections can raise intracranial pressure, making the timing of CT, LP, and airway decisions critical.

Key Medications

Ceftriaxone
2 g IV q12h for meningitis
Vancomycin
15–20 mg/kg IV loading/initial dose; exact dosing and interval vary by weight/renal function and local targets—check institutional protocol/reference.
Ampicillin
2 g IV q4h for Listeria coverage
Dexamethasone
10 mg IV q6h
Give before or with first antibiotic dose in suspected bacterial meningitis.
Acyclovir
10 mg/kg IV q8h using ideal/adjusted body weight per institutional guidance; check renal dosing carefully.
Cefepime
2 g IV q8h for healthcare-associated/neurosurgical risk scenarios
Meropenem
2 g IV q8h in selected nosocomial/neurosurgical cases; use local guidance.
Metronidazole
500 mg IV q6–8h for brain abscess/anaerobic source coverage
Levetiracetam
60 mg/kg IV load (max 4.5 g) or common adult loads 1.5–4.5 g IV for seizure management
Lorazepam
2–4 mg IV for active seizure
Pediatric note:
Neonates/children have different pathogen coverage and weight-based regimens; use a pediatric reference.

High-Yield Pearls

Altered mental status or focal deficits should shift your thinking from isolated meningitis toward encephalitis, mass lesion, or complicated infection.
CT-before-LP is for selected higher-risk patients; it is not required for every patient with suspected meningitis.
In adults >50 or immunocompromised, remember Listeria coverage with ampicillin.

Board Question

A 63-year-old man presents with fever, headache, neck stiffness, and confusion. Which is the best next step?

AObtain LP before any antibiotics to maximize CSF culture yield
BObtain CT head, then wait for LP results before treatment
CDraw blood cultures and start dexamethasone plus empiric antibiotics immediately
DGive analgesics and reassess after antipyretics Correct answer:
CExplanation: In suspected bacterial meningitis, antimicrobial therapy should not be delayed for LP or CT when these will take time. Dexamethasone should be given before or with the first antibiotic dose.

TheDaily Differential

Procedural Sedation

At the Bedside

Study Directive

More in Today's Issue

Singultus (Hiccups)

Thoracostomy

Thoracotomy

Central Nervous System Infections

Journal Watch

The Physician Who Never Stops

CT Case 105

Podcast Picks

Severe Traumatic Brain Injury with Dr. Dana Klavansky

Ep 216 Cardiac Arrest Update: Beyond the 2025 ACLS Guidelines Part 2 – Medications, Airway, Termination and Post-ROSC Care

Case of the Day