ERcast October 2022

IV Contrast and Lorazepam Shortages

Iodinated contrast shortage changes emergency imaging, but it does not erase diagnostic rigor: some abdominal CT indications remain accurate without contrast, while PE, mesenteric ischemia, and any angiographic question do not. Lorazepam shortage matters less clinically than many assume because seizures, alcohol withdrawal, and agitation all have workable alternatives. IV Contrast Shortage Imaging Noncontrast abdominal CT utility: Noncontrast CT remains highly useful for appendicitis, bowel obstruction, diverticulitis, and necrotizing fasciitis, with one appendicitis study suggesting adequate performance in patients with BMI above 23. Contrast essential indications: Contrast-enhanced CT remains the standard for mesenteric ischemia and any angiographic question; a noncontrast scan should not be used as a substitute when vascular pathology is the target. Pulmonary embolism workup: PE evaluation should start with Wells, PERC, and d-dimer in lower-risk patients because noncontrast chest CT has poor sensitivity, and high-risk patients still need CT pulmonary angiography. AAA and spinal infection: Suspected AAA is better served by bedside ultrasound plus early vascular surgery involvement, while spinal epidural abscess should push you toward MRI rather than a compromised CT pathway. Medicolegal documentation language: Shortage-era charting should explicitly note the global iodinated contrast shortage, ACR-guided alternative imaging, and that the changed diagnostic pathway was discussed with the patient. The bedside macro is worth hearing in the episode. Lorazepam Shortage Workarounds Seizure treatment substitutes: For active seizures, midazolam and diazepam are reasonable substitutes because benzodiazepine efficacy is not unique to lorazepam in this setting. Alcohol withdrawal choice: Lorazepam is not the preferred benzodiazepine for alcohol withdrawal, and phenobarbital is another strong option when usual pathways are disrupted. IV onset differences: By IV route, diazepam has the fastest onset at roughly 0 to 1 minute, ahead of lorazepam at 2 to 3 minutes and midazolam at 2 to 5 minutes. IM onset tradeoffs: By IM route, midazolam is the practical fastest option at about 15 minutes, while diazepam is unreliable because intramuscular absorption is variable. Single-dose duration nuance: Diazepam's single-dose clinical effect can fade in about 20 minutes despite its long half-life, a pharmacokinetic mismatch with practical implications we get into in the episode. Agitation alternatives: For acute agitation, ketamine, olanzapine, and haloperidol are viable non-lorazepam options when benzodiazepine supply is constrained.

Abortion Complications

Post-abortion complications present the same way in the ED whether the abortion was procedural, medication-related, or self-induced. Bleeding is most common, but retained products, polymicrobial infection, uterine trauma, and toxic exposures are the diagnoses that can rapidly become life-threatening. Emergency Evaluation of Abortion Complications Nonjudgmental history first: Complication risk turns on gestational age, method used, timing, bleeding, discharge, and systemic symptoms, and patients may not initially disclose a self-induced abortion. Pregnancy status and dating: Pregnancy status and last menstrual period anchor the workup because ongoing pregnancy, incomplete abortion, and alternative causes of bleeding all stay on the table early. Pelvic exam matters: A pelvic exam is essential because brisk bleeding, tissue at the os, discharge, or visible injury can quickly separate retained products from infection or trauma. Ultrasound for dangerous causes: Ultrasound is the key bedside imaging test for retained products and intrauterine findings, with a few practical limits and pitfalls we get into in the episode. Baseline resuscitation labs: CBC, coagulation studies, and type and screen help frame hemorrhage severity and transfusion readiness while the team rules out the highest-risk complications. Major Post-Abortion Complications Hemorrhage is most common: Bleeding is the leading complication, and instability or retained products should trigger urgent OB/GYN involvement rather than prolonged ED observation. Polymicrobial septic abortion: Infection after abortion is typically polymicrobial, including vaginal flora, anaerobes, and STI pathogens, and can progress to shock, DIC, organ failure, and future sterility. Source control mindset: Septic abortion is managed like any other sepsis syndrome, but retained products often make source control the decisive step. We walk through where D&C fits in the episode. Retained products of conception: Retained products are more common after unsafe abortion and usually declare themselves with bleeding or infection rather than a subtle exam finding. Genital tract and visceral trauma: Foreign body insertion can perforate the vagina, cervix, uterus, bowel, or bladder, and uterine artery injury is a recognized cause of massive hemorrhage. Imaging for perforation: FAST, pelvic ultrasound, and CT each have a role when intra-abdominal bleeding or perforation is suspected, with the sequencing nuances covered in the chapter. Chemical and Medication Toxicity Caustic vaginal injury: Inserted caustic substances can cause chemical burns with local tissue damage to the vagina or uterus, so the exam has to look beyond bleeding alone. Methotrexate toxicity clues: Methotrexate exposure can produce dermatologic findings plus liver and renal toxicity, and knowing the reported dose helps guide poison-center-informed management. Herbal abortifacient toxicity: Pennyroyal and black cohosh are classic herbal abortifacients; they are unreliable and can cause serious hepatic or renal injury. Call Poison Control early. Misoprostol and mifepristone context: Medication abortion commonly uses mifepristone 200 mg followed by misoprostol, but in the ED the priority is recognizing complications rather than reconstructing the outpatient regimen.

Lit Matters #1: Nitrofurantoin is Safe and Effective for Uncomplicated UTIs.

Nitrofurantoin remains a strong first-line choice for uncomplicated cystitis in healthy women, with a cleaner adverse-event profile than several commonly prescribed alternatives. For outpatient UTI treatment, antibiotic choice and duration both matter for rash, diarrhea, C. difficile risk, and microbiome disruption. Antibiotic Choice in Uncomplicated UTI Nitrofurantoin safety signal: Nitrofurantoin served as the reference drug in a 1.16 million-patient comparison and was associated with fewer adverse events than fluoroquinolones, TMP-SMX, and many beta-lactams. Fluoroquinolone downside: Fluoroquinolones stood out for microbiome-related harm, including a marked increase in C. difficile diarrhea with a hazard ratio of 4.22 versus nitrofurantoin. TMP-SMX rash risk: TMP-SMX carried substantially more cutaneous reactions, with rash risk more than doubled compared with nitrofurantoin, while remaining a guideline-listed first-line option. Resistance landscape: Local susceptibility still matters: TMP-SMX resistance can approach 25%, while nitrofurantoin resistance is often under 2% for common uropathogens. We get into how that changes empiric choices in the episode. Duration and disruption: Longer antibiotic courses tracked with more microbiome-related adverse effects, reinforcing that uncomplicated cystitis treatment should stay as short as evidence allows.

Essentials Masterclass: Migraine Cocktail

Acute headache treatment in the ED starts with ruling out dangerous secondary causes while relieving symptoms aggressively. Migraine cocktails work best when anti-dopaminergic agents lead, opioids stay off the table, and symptom response never substitutes for the diagnostic workup. ED Migraine Cocktail Strategy Dangerous headache differential: Subarachnoid hemorrhage, CNS infection, cervical artery dissection, and cerebral venous sinus thrombosis stay on the board even when the exam is reassuring, a diagnostic mindset we sharpen in the episode. Treatment response trap: Headache resolution does not rule out a dangerous cause, so the diagnostic workup should run independently of symptom control rather than being guided by whether the cocktail works. First-line antidopaminergic therapy: IV anti-dopaminergic agents are the preferred first move for acute migraine, with metoclopramide, prochlorperazine, droperidol, and haloperidol forming the core options. Why not opioids: Opioids are not recommended for ED headache management, including a Level 1 ACEP recommendation against them because they worsen variability in care without addressing migraine biology. Second-line ketorolac ceiling: When the first dose is incomplete, another anti-dopaminergic plus IV ketorolac is a strong next step, and ketorolac has an analgesic ceiling at 15 mg rather than higher doses. Refractory rescue options: By the third and fourth line, ergot alkaloids, peripheral nerve blocks, and selected emerging therapies enter the picture, with practical sequencing nuances we get into in the chapter. Adjuncts and Emerging Therapies Fluids and diphenhydramine limits: IV fluids are not first-line unless dehydration is present, and diphenhydramine offers only modest headache benefit while reliably adding grogginess. Ergot contraindication check: Ergot alkaloids can help refractory migraine but are contraindicated in cardiovascular disease and after recent triptan use, a safety pause worth making before escalation. Peripheral nerve block role: Peripheral nerve blocks are relatively easy bedside interventions for refractory primary headache, typically using lidocaine or bupivacaine when repeated medications are failing. Propofol as emerging option: Propofol is among the best-studied emerging rescue therapies for refractory migraine, used in subanesthetic dosing rather than procedural-sedation style administration. Ketamine mixed evidence: Ketamine has a more inconsistent track record than propofol in acute migraine, so it is not a first-line agent despite growing familiarity with subdissociative dosing. Other nonopioid alternatives: Magnesium, valproic acid, and octreotide round out the nonopioid rescue list for selected refractory headaches. We cover where these fit on the show.

Lit Matters #2: Poor Outcomes Associated with Vitamin C in Sepsis

High-dose IV vitamin C in septic shock is not benign. In adults with sepsis on vasopressors in the ICU, a large blinded randomized trial found worse 28-day outcomes with vitamin C, directly challenging the long-running “what could it hurt?” mindset. Vitamin C in Septic Shock Practice-changing trial signal: In vasopressor-dependent sepsis, IV vitamin C was associated with a higher rate of death or persistent organ dysfunction at 28 days, a rare finding for a therapy often framed as harmless. Large blinded ICU trial: This was an international double-blind RCT across 35 ICUs with 863 patients, giving the negative signal more weight than the earlier small single-center enthusiasm. Composite outcome details: The primary endpoint combined death with ongoing vasopressors, mechanical ventilation, or renal replacement therapy on day 28, anchoring the result in patient-centered organ support. Mortality trend without benefit: Mortality alone was numerically higher with vitamin C, and none of the secondary outcomes showed a compensating advantage in organ recovery, quality of life, or biomarkers. Why earlier excitement faded: Prior positive studies often bundled vitamin C with hydrocortisone and thiamine, while seven randomized trials overall have been mixed and methodologically uneven. We get into why that early signal was so persuasive in the episode. Therapeutic humility lesson: Sepsis care is full of biologically plausible treatments that fail when tested, and vitamin C is a sharp reminder that antioxidant theory does not equal bedside benefit.

Heart Failure Disposition

Acute heart failure disposition is high stakes: U.S. ED admission rates exceed 80%, yet short-term mortality and revisit risk remain substantial whether patients are admitted or discharged. Safe discharge starts with identifying immediate admission red flags, then pairing a reassuring ED evaluation with selective risk stratification. Acute Heart Failure Disposition Immediate admission red flags: New heart failure, ischemic ECG changes, suspected MI, need for respiratory support or vasopressors, and end-organ injury are high-risk features that should push disposition toward admission. Reassuring ED evaluation: Possible discharge begins only after symptom improvement with diuresis, baseline oxygenation, stable systolic blood pressure, and normal renal, liver, electrolyte, and troponin testing. Ottawa score role: The Ottawa Heart Failure Risk Score is best used to supplement clinical judgment and shared decision-making; even a score of 0 still carries an adverse event rate of 2.8%. Alternative risk tools: EHMRG targets 7-day mortality and MEESSI predicts 30-day mortality, but both are less practical at the bedside because of multiple categories and calculator complexity. We get into where they still fit in the episode. Imaging over natriuretic peptides: Lung ultrasound is over 90% sensitive and specific for pulmonary edema, while BNP is sensitive but nonspecific and easily confounded by renal failure, atrial fibrillation, sepsis, and obesity. Discharge safety net: Discharged patients need reliable medication and diet adherence, strict return precautions, and follow-up within 1 week with heart failure clinic or primary care.

Lit Matters #3: Routine Fluid Bolus During Intubation Doesn’t Prevent Hypotension.

Peri-intubation hypotension is common in critically ill adults, and a routine pre-intubation fluid bolus did not reduce cardiovascular collapse in a multicenter ICU randomized trial. For ED and ICU airway management, this sharpens the question of who actually benefits from fluids before induction. Peri-intubation Fluid Bolus Evidence Cardiovascular collapse outcome: The composite endpoint was clinically hard-edged: new or increased vasopressor use, severe hypotension, cardiac arrest, or death around intubation, making the negative result hard to dismiss. Routine 500 mL bolus: A 500 mL IV fluid bolus before or during intubation did not significantly lower cardiovascular collapse compared with no bolus, despite longstanding guideline support for the practice. Positive pressure rationale: The physiologic argument was reduced venous return after induction and positive-pressure ventilation, but even in patients expected to benefit most, no subgroup signal emerged. Pragmatic airway trial design: Clinicians were otherwise free to run the intubation, including induction drugs and rescue hemodynamics, so the trial reads like real-world ICU airway practice. We get into what that means at the bedside in the episode. What the negative trial means: This study argues against reflexive fluids as a universal peri-intubation hypotension prevention strategy, while leaving room for selective bolus use when the clinical picture clearly suggests preload responsiveness.

Acid Base (All About That Base)

Acid-base disorders become readable when you anchor on pH, PaCO2, serum bicarbonate, and the anion gap in a fixed sequence. A normal pH does not exclude serious mixed metabolic and respiratory processes, and an anion gap of 20 or more should trigger a focused search for occult acidosis. Systematic Blood Gas Interpretation Primary process framing: Acidemia and alkalemia describe the net pH effect, while acidosis and alkalosis name the underlying process seen in PaCO2 and bicarbonate; keeping those terms separate prevents early misclassification. Four-step interpretation sequence: Start with pH, then pair PaCO2 with serum bicarbonate, then calculate the anion gap, then use the delta gap to uncover hidden mixed disorders. We walk through the sequence in the episode. Serum bicarbonate preference: The bicarbonate on the metabolic panel is the value to trust; blood-gas bicarbonate is calculated and can mislead the entire interpretation if you build from it. Mixed disorder mindset: Do not assume one primary disturbance: critically ill patients can carry as many as three simultaneous acid-base processes, especially when the pH looks deceptively normal. Compensation has limits: The body never fully compensates for a primary acid-base disorder, so a normal pH in the setting of an anion-gap acidosis implies at least one additional process. Anion Gap and Hidden Acidosis High-gap trigger point: An anion gap of 20 or greater is a meaningful red flag for true anion-gap metabolic acidosis, not just biologic noise, and should prompt an immediate etiologic workup. High-yield gap labs: When the gap is elevated in a sick undifferentiated patient, the first send-outs are lactate, salicylate, acetaminophen, serum osmolality, and ketones. KULT differential anchor: KULT—ketones, uremia, lactate, toxins—covers the common ED causes of anion-gap acidosis and keeps the differential practical under pressure. Delta gap purpose: The delta gap asks whether the fall in bicarbonate matches the rise in the gap, exposing a concomitant metabolic alkalosis or non-gap acidosis without relying on gestalt alone. Normal pH warning: A patient can have normal pH, normal PaCO2, and normal bicarbonate yet still harbor a clinically important anion-gap acidosis; that paradox is worth hearing in the chapter. ABG Versus VBG Pearls VBG usual role: A VBG is appropriate for most emergency acid-base questions because the pH and PaCO2 trend closely enough to identify the primary disorder in routine practice. Respiratory acidosis screen: A VBG PCO2 below 45 effectively rules out clinically important respiratory acidosis, giving you a fast bedside screen before committing to arterial sampling. When ABG matters: If you need an accurate PaO2 or tightly precise PaCO2, get an ABG; neurotrauma is a common setting where that extra precision changes management.