Core EM - Emergency Medicine Podcast

Show Notes

Core EM Modular CME Course

Maximize your commute with the new Core EM Modular CME Course, featuring the most essential content distilled from our top-rated podcast episodes. This course offers 12 audio-based modules packed with pearls! Information and link below. 

Course Highlights:

• Credit: 12.5 AMA PRA Category 1 Credits™


• Curriculum: Comprehensive coverage of Core Emergency Medicine,  with 12 modules spanning from Critical Care to Pediatrics.


• Cost:
  
  
  
  • Free for NYU Learners
  
  
  • $250 for Non-NYU Learners
  
  
  
  

Click Here to Register and Begin Module 1

1. Core Definition & Hemodynamic Profile

• 
  

  Clinical Paradox: Congestive symptoms (pulmonary edema, JVD, peripheral edema) in the setting of a hyperdynamic, supranormal cardiac function.

  
  


• 
  

  Hemodynamic Criteria:

  
  
  
  
  • 
    

    Cardiac Index (CI): >4.0 L/min/m2.

    
    
  
  
  • 
    

    Cardiac Output (CO): $>8\text{ L/min}$.

    
    
  
  
  • 
    

    Systemic Vascular Resistance (SVR): Pathologically low (vasodilated or shunted state).

    
    
  
  
  
  


• 
  

  The “Warm” Phenotype: Unlike standard HFrEF/HFpEF (often “Cold and Wet”), HOHF presents as “Warm and Wet” due to low SVR and bounding pulses.

  
  

2. Pathophysiology: The Hemodynamic Paradox

• 
  

  Primary Insult: Decreased SVR (either via peripheral vasodilation or arteriovenous shunting).

  
  


• 
  

  Effective Arterial Blood Volume: Paradoxically low despite high total CO.

  
  


• 
  

  Neurohormonal Cascade:

  
  
  
  
  • 
    

    Activation of Renin-Angiotensin-Aldosterone System (RAAS).

    
    
  
  
  • 
    

    Increased Sympathetic Nervous System tone.

    
    
  
  
  • 
    

    Increased Antidiuretic Hormone (ADH) secretion.

    
    
  
  
  
  


• 
  

  Resultant State: Avid renal salt and water retention leading to massive plasma volume expansion.

  
  


• 
  

  Cardiac Response: Chronic volume overload $\to$ eccentric remodeling $\to$ chamber dilation $\to$ eventual secondary myocardial failure/dilated cardiomyopathy.

  
  

3. Differential Diagnosis: Etiological “Buckets”

Category A: Increased Metabolic Demand (Systemic)

• 
  

  Hyperthyroidism/Thyrotoxicosis:

  
  
  
  
  • 
    

    Direct T3 effects: increased chronotropy/inotropy.

    
    
  
  
  • 
    

    Indirect effects: metabolic byproduct accumulation causing peripheral vasodilation.

    
    
  
  
  
  


• 
  

  Myeloproliferative Disorders:

  
  
  
  
  • 
    

    High cell turnover and increased oxygen consumption drive compensatory CO increase.

    
    
  
  
  
  


• 
  

  Sepsis (Hyperdynamic Phase):

  
  
  
  
  • 
    

    Cytokine-mediated global vasodilation.

    
    
  
  
  • 
    

    Note: Often transient; may transition to sepsis-induced myocardial depression.

    
    
  
  
  
  

Category B: Peripheral Vascular Effects (Shunting/Vasodilation)

• 
  

  Arteriovenous Fistulas (AVF) / Malformations (AVM):

  
  
  
  
  • 
    

    Most Common Cause: Iatrogenic AVF for Hemodialysis (ESRD population).

    
    
  
  
  • 
    

    Bypasses high-resistance capillary beds, dumping arterial blood directly into venous circulation.

    
    
  
  
  
  


• 
  

  Chronic Liver Disease (Cirrhosis):

  
  
  
  
  • 
    

    Formation of “spider angiomata” and internal AV shunts.

    
    
  
  
  • 
    

    Impaired clearance of endogenous vasodilators (e.g., Nitric Oxide).

    
    
  
  
  
  


• 
  

  Thiamine Deficiency (Wet Beriberi):

  
  
  
  
  • 
    

    Accumulation of pyruvate/lactate $\to$ systemic vasodilation.

    
    
  
  
  • 
    

    Histopathology: Vacuolation, myofiber hypertrophy, and interstitial edema.

    
    
  
  
  
  


• 
  

  Chronic Lung Disease:

  
  
  
  
  • 
    

    Hypoxia/Hypercapnia-driven systemic vasodilation.

    
    
  
  
  • 
    

    Concomitant pulmonary HTN (RV remodeling) but preserved/high LV output.

    
    
  
  
  
  


• 
  

  Others: Paget’s disease of bone (extensive micro-shunting), Carcinoid syndrome, Mitochondrial diseases, Acromegaly, Erythroderma.

  
  

4. Special Focus: Hemodialysis Access-Induced HOHF

Physiologic Phases of AVF Creation:

1. 
   

   Acute Phase:

   
   
   
   
   1. 
      

      Immediate $\downarrow$ SVR.

      
      
   
   
   2. 
      

      $\uparrow$ Stroke volume and Heart Rate (SNS-mediated).

      
      
   
   
   3. 
      

      Endothelial shear stress $\to$ Nitric Oxide release $\to$ further arterial dilation.

      
      
   
   
   
   


2. 
   

   Subacute Phase (Days to 2 Weeks):

   
   
   
   
   1. 
      

      RAAS-driven volume expansion.

      
      
   
   
   2. 
      

      $\uparrow$ Right Atrial, Pulmonary Artery, and LV End-Diastolic Pressures (LVEDP).

      
      
   
   
   3. 
      

      Natriuretic peptide surge (BNP/ANP) peaks around Day 10.

      
      
   
   
   
   


3. 
   

   Chronic Phase (Weeks to Months):

   
   
   
   
   1. 
      

      Adaptive hypertrophy.

      
      
   
   
   2. 
      

      Decompensation occurs when dilation exceeds contractility limits.

      
      
   
   
   
   

5. Point-of-Care Physical Exam & Maneuvers

• 
  

  Nicoladoni-Branham Sign (Pathognomonic for Shunt-driven HOHF):

  
  
  
  
  • 
    

    Maneuver: Manually compress the AVF (or inflate cuff to $>50\text{ mmHg}$ above SBP) for 30 seconds.

    
    
  
  
  • 
    

    Positive Result: Reflexive bradycardia or a transient rise in systemic BP.

    
    
  
  
  • 
    

    Significance: Confirms the shunt is a major contributor to the cardiac workload.

    
    
  
  
  
  


• 
  

  Peripheral Pulse Assessment:

  
  
  
  
  • 
    

    Water Hammer Pulses: Rapid upstroke and collapse.

    
    
  
  
  • 
    

    Quincke’s Pulse: Visible capillary pulsations in the nail beds.

    
    
  
  
  • 
    

    Traube’s Sign: “Pistol-shot” sounds auscultated over the femoral arteries.

    
    
  
  
  
  


• 
  

  Volume Status: Rales, S3 gallop, peripheral edema (standard HF signs).

  
  

6. Diagnostic Workup (Technical Targets)

POCUS / Echocardiography:

• 
  

  Left Ventricle: Hyperdynamic function; EF typically $>60\%$.

  
  


• 
  

  Left Atrium: Significant dilation (Left Atrial Volume Index >34 mL/m2; Case study noted 72 mL/m2).

  
  


• 
  

  IVC: Plethoric with minimal respiratory variation.

  
  


• 
  

  Doppler: High flow velocities across the AV access if applicable.

  
  

Laboratory Evaluation:

• 
  

  BNP/NT-proBNP: Often markedly elevated (e.g., $>70,000$ in severe cases), though mean values in literature hover around $700\text{–}800\text{ pg/mL}$.

  
  


• 
  

  Hematology: CBC to evaluate for severe anemia (trigger for HOHF if $\text{Hgb}<7\text{–}8\text{ g/dL}$) or myeloproliferative markers.

  
  


• 
  

  Endocrine/Metabolic: TSH (Thyrotoxicosis), Serum Thiamine (Beriberi), LFTs (Cirrhosis).

  
  

7. Management Strategy: A Stepwise Approach

Phase 1: Immediate Stabilization (Volume Offloading)

• 
  

  Diuresis: Aggressive IV loop diuretics (Bumetanide/Furosemide).

  
  


• 
  

  Ultrafiltration: Preferred in ESRD patients failing to respond to dialysis or with refractory congestion.

  
  


• 
  

  Vasodilator Caution: Avoid aggressive Nitroglycerin or ACE-inhibitors initially.

  
  
  
  
  • 
    

    Rationale: Baseline SVR is already pathologically low; further reduction may precipitate profound hypotension/circulatory collapse.

    
    
  
  
  
  

Phase 2: Targeted Therapy (Etiology Specific)

• 
  

  Anemia: Transfuse to goal $\text{Hgb}>7\text{–}8\text{ g/dL}$ to reduce demand.

  
  


• 
  

  Beriberi: High-dose IV Thiamine ($100\text{–}500\text{ mg}$).

  
  


• 
  

  Thyrotoxicosis: Beta-blockers (Propranolol) + Antithyroid meds (PTU/Methimazole).

  
  

Phase 3: Surgical/Interventional Salvage (Refractory AVF Cases)

1. 
   

   Closure of Accessory Sites: If multiple fistulas exist, close the non-dominant/unused sites.

   
   


2. 
   

   Flow Reduction (Banding): Surgical narrowing of the fistula to target flow $<600\text{ mL/min}$.

   
   


3. 
   

   RUDI Procedure: Revision Using Distal Inflow (moving inflow to a smaller, more distal artery).

   
   


4. 
   

   Ligation: Complete closure of the AVF.

   
   
   
   
   • 
     

     Note: Requires bridge to Tunneled Dialysis Catheter or AV graft (higher resistance than fistulas).

     
     
   
   
   
   

8. Key Clinical Takeaways

• 
  

  The “Normal EF” Trap: Do not be reassured by an EF of $55\text{–}65\%$; in the context of pulmonary edema and high CO, this is potentially HOHF.

  
  


• 
  

  Pulse Pressure: Look for a wide pulse pressure (e.g., $180/60$) as a marker of low SVR.

  
  


• 
  

  ESRD Logic: If an ESRD patient is “wet” immediately after HD, the problem is likely flow (AVF), not just fluid.

  
  

Show Notes

Core EM Modular CME Course

Maximize your commute with the new Core EM Modular CME Course, featuring the most essential content distilled from our top-rated podcast episodes. This course offers 12 audio-based modules packed with pearls! Information and link below. 

Course Highlights:

• Credit: 12.5 AMA PRA Category 1 Credits™


• Curriculum: Comprehensive coverage of Core Emergency Medicine,  with 12 modules spanning from Critical Care to Pediatrics.


• Cost:
  
  
  
  • Free for NYU Learners
  
  
  • $250 for Non-NYU Learners
  
  
  
  

Click Here to Register and Begin Module 1

I. Phase 1: Stabilization (Minutes 0–10)

The “Rearrest” Window & Pathophysiology

• High-Risk Period: Rearrest rates reach 30% within the first minutes post-ROSC.
  
  


• Shock Incidence: Two-thirds of patients develop profound hypotension/shock as initial resuscitative efforts subside.
  
  


• Catecholamine Washout: Super-physiologic “code-dose” epinephrine (1mg IV) typically wears off within ~3 minutes post-ROSC, leading to predictable hemodynamic collapse.
  
  


• Secondary Injuries: Evaluate for “CPR-induced trauma” (blunt thoracic trauma, rib fractures, pneumothorax, liver/splenic lacerations).
  
  

Immediate Resuscitative Actions

• Vascular Access:
  
  
  
  • Transition rapidly from IO to reliable IV access within 1–2 minutes.
    
    
  
  
  • Prioritize Intraosseous (IO) placement within 5 minutes if IV attempts fail; intra-arrest data suggests no significant difference in early outcomes.
    
    
  
  
  
  


• Vasoactive “Bridge”:
  
  
  
  • Maintain a “bolus-dose” pressor at the bedside for immediate push-dose titration.
    
    
  
  
  • Options: Phenylephrine, dilute Epinephrine, or dilute Norepinephrine (titrated to effect rather than rigid dosing).
    
    
  
  
  
  


• Physician-Specific Task: Arterial Line:
  
  
  
  • Goal: Placement within 5 minutes of ROSC.
    
    
  
  
  • Preferred Site: Femoral (by landmarks/blind if necessary) for speed; should be a <2-minute procedure.
    
    
  
  
  • Utility: Immediate detection of rearrest and beat-to-beat titration of vasopressors.
    
    
  
  
  
  

II. Phase 2: Diagnostic Workup (Minutes 10–40)

Etiology Epidemiology

• ACS Shift: Acute Coronary Syndrome (ACS) is the cause in only 6–10% of resuscitated survivors (lower than historical estimates).
  
  


• Common Etiologies:


• Respiratory: COPD, pneumonia, mucus plugging.
  
  
  
  
  
  
  • Cardiac: Arrhythmia (cardiomyopathy/scar), RV failure (PE), or LV failure.
    
    
  
  
  • Neurological: Intracranial hemorrhage (SAH/ICH), status epilepticus (4–5%).
    
    
  
  
  • Metabolic: Dialysis-related disarray/hyperkalemia.
    
    
  
  
  • Toxicology: Overdose accounts for ~10% of cases in urban centers.
    
    
  
  
  
  

The “Broad Net” Strategy

• “Rainbow Labs”: Comprehensive panel including toxicology and serial biomarkers.
  
  


• Pan-Scan Protocol:
  
  
  
  • Components: CT/CTA Head/Neck, Contrast CT Chest/Abdomen/Pelvis.
    
    
  
  
  • Diagnostic Yield: 50% for clinically significant findings (causes or consequences of arrest).
    
    
  
  
  • Contrast Risk: Negligible (1–2% increase in AKI risk) compared to the high diagnostic utility.
    
    
  
  
  
  


• Avoid Anchoring: Do not assume ischemic EKG changes are the cause; they are frequently a consequence of the global arrest-induced ischemia.
  
  

III. Hemodynamic & Respiratory Targets

Mean Arterial Pressure (MAP)

• Autoregulation Shift: In acute brain injury/post-arrest, the lower limit of cerebral autoregulation shifts right, often requiring MAPs of 110–120 mmHg for adequate perfusion.


• Clinical Target: Aim for MAP >80 mmHg.
  
  


• The BOX Trial Nuance: While the BOX trial showed no difference between MAP 63 vs. 77, its cohort (Denmark) had exceptionally high survival rates (70% back to work) and short response times, which may not generalize to North American populations with lower shockable rhythm incidence.
  
  


• Permissive Hypertension: If the patient is “self-driving” to higher pressures, do not aggressively lower them, as this may be a physiologic demand for cerebral blood flow.
  
  

Ventilation and Oxygenation

• PaCO2 Management:
  
  
  
  • Target: High-normal to slightly hypercarbic (45–55 mmHg).
    
    
  
  
  • Rationale: Avoid accidental hyperventilation (PaCO2 <30), which can cut cerebral blood flow by 50%.
    
    
  
  
  
  


• PaO2 Management: Maintain normoxia; avoid extreme hyperoxia, though trial data (BOX trial) suggests small variances (70 vs 90 mmHg) are likely neutral.
  
  

IV. Neurological Prognostication & Communication

The “Stunned” Brain

• Anoxic Depolarization: Occurs within ~2 minutes of pulselessness as ATP-dependent ion pumps fail.
  
  


• Clinical Pitfall: Early neurological exams (absent pupils, no motor response) are unreliable in the first hours as they reflect global neuronal “stunning” rather than definitive permanent injury.
  
  


• Time Horizon: Meaningful recovery is measured in days/weeks, not minutes/hours.
  
  

Family Engagement

• Presence: Bring family to the bedside immediately, including during procedures or continued resuscitation.
  
  


• Psychological Impact: Significantly reduces PTSD, anxiety, and depression in survivors’ families.
  
  


• Prognostic Honesty: Explicitly state “I don’t know” regarding etiology and outcome.
  
  


• Framing: Define “No News” as the best possible early outcome (preventing rearrest and stabilization).

Show Notes

Core EM Modular CME Course

Maximize your commute with the new Core EM Modular CME Course, featuring the most essential content distilled from our top-rated podcast episodes. This course offers 12 audio-based modules packed with pearls! Information and link below. 

Course Highlights:

• Credit: 12.5 AMA PRA Category 1 Credits™


• Curriculum: Comprehensive coverage of Core Emergency Medicine,  with 12 modules spanning from Critical Care to Pediatrics.


• Cost:
  
  
  
  • Free for NYU Learners
  
  
  • $250 for Non-NYU Learners
  
  
  
  

Click Here to Register and Begin Module 1

Patient Presentation & Workup

• Patient: 36-year-old male, currently shelter-domiciled, presenting with 3 weeks of generalized weakness, fevers, weight loss, and headaches.


• Vitals (Initial): BP 147/98, HR 150s, Temp 100.2°F, RR 18, O2 99% RA.


• Clinical Evolution: Initial assessment noted cachexia and a large ventral hernia. Following initial workup, the patient became acutely altered (A&O x0) and febrile to 102.9°F.


• Physical Exam Findings:
  
  
  
  • Brudzinski Sign: Positive (knees flexed upward upon passive neck flexion).
  
  
  • Kernig Sign: Discussed as highly specific (resistance/pain during knee extension with hip flexed at 90°).
  
  
  • Meningeal Triad: Fever, nuchal rigidity, and AMS (present in 40% of cases; 95% of patients have at least two of the four cardinal symptoms including headache).
  
  
  
  


• Imaging:
  
  
  
  • Chest X-ray: Scattered opacities (pneumonia) and a small pneumothorax.
  
  
  • CT Abdomen/Pelvis: Confirmed asplenia (secondary to 2011 GSW/exploratory laparotomy).
  
  
  • Head CT: Ventricle enlargement concerning for obstructive hydrocephalus and diffuse sulcal effacement.
  
  
  
  

CSF Analysis & Microbiology

• Bacterial Meningitis
  
  
  
  • Opening Pressure: Elevated (Normal is $<170$ mm H2​O).
  
  
  • Color: Cloudy or turbid.
  
  
  • Gram Stain: Positive in 60%–80% of cases before antibiotics; drops to 7%–41% after antibiotics.
  
  
  • Cell Count: Very high ($>1000$–2000/mm3 WBC); dominated by neutrophils ($>80\%$ PMN).
  
  
  • Glucose: Low ($<40$ mg/dL); CSF/blood glucose ratio is $<0.3$–$0.4$.
  
  
  • Protein: High ($>200$ mg/dL).
  
  
  • Cytology: Negative.
  
  
  
  


• Viral Meningitis
  
  
  
  • Opening Pressure: Normal.
  
  
  • Color: Clear or bloody.
  
  
  • Gram Stain: Negative.
  
  
  • Cell Count: Slightly elevated (<300/mm3 WBC); dominated by lymphocytes ($<20\%$ PMN).
  
  
  • Glucose: Normal.
  
  
  • Protein: Moderately elevated ($<200$ mg/dL).
  
  
  • Cytology: Negative.
  
  
  
  


• Fungal Meningitis
  
  
  
  • Opening Pressure: Normal to elevated.
  
  
  • Color: Clear or cloudy.
  
  
  • Gram Stain: Negative.
  
  
  • Cell Count: Elevated (<500/mm3 WBC).
  
  
  • Glucose: Normal to slightly low.
  
  
  • Protein: High ($>200$ mg/dL).
  
  
  • Cytology: Negative.
  
  
  
  


• Neoplastic (Cancer-related) Meningitis
  
  
  
  • Opening Pressure: Normal.
  
  
  • Color: Clear or cloudy.
  
  
  • Gram Stain: Negative.
  
  
  • Cell Count: Elevated (<300/mm3 WBC).
  
  
  • Glucose: Normal to slightly low.
  
  
  • Protein: High ($>200$ mg/dL).
  
  
  • Cytology: Positive (this is the key differentiator).
  
  
  
  

Management Protocol

• Immediate Treatment: Early administration of antibiotics/antivirals is critical to reduce mortality.
  
  
  
  • Antibiotics: Ceftriaxone 2g IV q12h + Vancomycin (or Rifampin in cephalosporin-resistant areas).
  
  
  • Listeria Coverage: Add Ampicillin for patients > 50 years old.
  
  
  • Antivirals: Acyclovir 10 mg/kg q8h.
  
  
  • Steroids: Dexamethasone 10 mg IV q6h for 4 days (proven to reduce mortality and improve outcomes).
  
  
  
  


• Surgical Intervention: Neurosurgery performed an emergent EVD in the ED to relieve pressure from obstructive hydrocephalus.


• Post-Exposure Prophylaxis: Indicated only for N. meningitidis (not S. pneumoniae) for contacts < 24 hours from diagnosis.
  
  
  
  • Regimens: Rifampin for 2 days, single-dose Ciprofloxacin, or IM Ceftriaxone (if pregnant).
  
  
  
  

Stats & Clinical Pearls: Austrian Syndrome

• The Triad: Concurrent pneumonia, endocarditis, and meningitis caused by Streptococcus pneumoniae.


• Risk Factors: Asplenia (due to the spleen’s role in filtering encapsulated bacteria), alcohol use disorder, and immunosuppression.


• Mortality Rate: Extremely high at 28%; mortality is highest when there is CNS involvement.


• Incidence: Worldwide, S. pneumoniae is the leading cause of bacterial meningitis, accounting for 3,000–6,000 cases annually.

Show Notes

Core EM Modular CME Course

Maximize your commute with the new Core EM Modular CME Course, featuring the most essential content distilled from our top-rated podcast episodes. This course offers 12 audio-based modules packed with pearls! Information and link below. 

Course Highlights:

• Credit: 12.5 AMA PRA Category 1 Credits™


• Curriculum: Comprehensive coverage of Core Emergency Medicine,  with 12 modules spanning from Critical Care to Pediatrics.


• Cost:
  
  
  
  • Free for NYU Learners
  
  
  • $250 for Non-NYU Learners
  
  
  
  

Click Here to Register and Begin Module 1

The Clinical Case

• Presentation: 60-year-old male with a history of HTN and asthma.


• EMS Findings: Severe respiratory distress, SpO₂ in the 60s on NRB, HR 120, BP 230/180.


• Exam: Diaphoretic, diffuse crackles, warm extremities, pitting edema, and significant fatigue/work of breathing.


• Pre-hospital meds: NRB, Duonebs, Dexamethasone, and IM Epinephrine (under the assumption of severe asthma/anaphylaxis).

Differential Diagnosis for the Hypoxic/Tachypneic Patient

• Pulmonary: Asthma/COPD, Pneumonia, ARDS, PE, Pneumothorax, Pulmonary Edema, ILD, Anaphylaxis.


• Cardiac: CHF, ACS, Tamponade.


• Systemic: Anemia, Acidosis.


• Neuro: Neuromuscular weakness.

What is SCAPE?

Sympathetic Crashing Acute Pulmonary Edema (SCAPE) is characterized by a sudden, massive sympathetic surge leading to intense vasoconstriction and a precipitous rise in afterload.

• Pathophysiology: Unlike HFrEF, these patients are often euvolemic or even hypovolemic. The primary issue is fluid maldistribution (fluid shifting from the vasculature into the lungs) due to extreme afterload.

Bedside Diagnosis: POCUS vs. CXR

POCUS is the gold standard for rapid bedside diagnosis.

• Lung Ultrasound: Look for diffuse B-lines (≥3 in ≥2 bilateral zones).


• Cardiac: Assess LV function and check for pericardial effusion.


• Why not CXR? A meta-analysis shows LUS has a sensitivity of ~88% and specificity of ~90%, whereas CXR sensitivity is only ~73%. Importantly, up to 20% of patients with decompensated HF will have a normal CXR.

Management Strategy

1. NIPPV (CPAP or BiPAP)

Start NIPPV immediately to reduce preload/afterload and recruit alveoli.

• Settings: CPAP 5–8 cm H₂O or BiPAP 10/5 cm H₂O. Escalate EPAP quickly but keep pressures to avoid gastric insufflation.


• Evidence: NIPPV reduces mortality (NNT 17) and intubation rates (NNT 13).

2. High-Dose Nitroglycerin

The goal is to drop SBP to < 140–160 mmHg within minutes.

• No IV Access: 3–5 SL tabs (0.4 mg each) simultaneously.


• IV Bolus: 500–1000 mcg over 2 minutes.


• IV Infusion: Start at 100–200 mcg/min; titrate up rapidly (doses > 800 mcg/min may be required).


• Safety: ACEP policy supports high-dose NTG as both safe and effective for hypertensive HF. Use a dedicated line/short tubing to prevent adsorption issues.

3. Refractory Hypertension

If SBP remains > 160 mmHg despite NIPPV and aggressive NTG, add a second vasodilator:

• Clevidipine: Ultra-short-acting calcium channel blocker (titratable and rapid).


• Nicardipine: Effective alternative for rapid BP control.


• Enalaprilat: Consider if the above are unavailable.

Troubleshooting & Pitfalls

The “Mask Intolerant” Patient

Hypoxia is the primary driver of agitation. NIPPV is the best sedative. * Pharmacology: If needed, use small doses of benzodiazepines (Midazolam 0.5–1 mg IV).

• AVOID Morphine: Data suggests higher rates of adverse events, invasive ventilation, and mortality. A 2022 RCT was halted early due to harm in the morphine arm (43% adverse events vs. 18% with midazolam).

The Role of Diuretics

In SCAPE, diuretics are not first-line.

• The problem is redistribution, not volume excess. Diuretics will not help in the first 15–30 minutes and may worsen kidney function in a (relatively) hypovolemic patient.


• Delay Diuretics until the patient is stabilized and clear systemic volume overload (edema, weight gain) is confirmed.

Disposition

• Admission: Typically requires CCU/ICU for ongoing NIPPV and titration of vasoactive infusions.


• Weaning: As BP normalizes and work of breathing improves, infusions and NIPPV can be gradually tapered.

Take-Home Points

1. Recognize SCAPE: Hyperacute dyspnea + severe HTN. Trust your POCUS (B-lines) over a “clear” CXR.


2. NIPPV Immediately: Don’t wait. It saves lives and prevents tubes.


3. High-Dose NTG: Use boluses to “catch up” to the sympathetic surge. Don’t fear the dose.


4. Avoid Morphine: Use small doses of benzos if the patient is struggling with the mask.


5. Lasix Later: Prioritize afterload reduction over diuresis in the hyperacute phase.

Show Notes

Core EM Modular CME Course

Maximize your commute with the new Core EM Modular CME Course, featuring the most essential content distilled from our top-rated podcast episodes. This course offers 12 audio-based modules packed with pearls! Information and link below. 

Course Highlights:

• Credit: 12.5 AMA PRA Category 1 Credits™


• Curriculum: Comprehensive coverage of Core Emergency Medicine,  with 12 modules spanning from Critical Care to Pediatrics.


• Cost:
  
  
  
  • Free for NYU Learners
  
  
  • $250 for Non-NYU Learners
  
  
  
  

Click Here to Register and Begin Module 1

What is prehospital blood transfusion

• 
  

  Administration of blood products in the field prior to hospital arrival

  
  


• 
  

  Aimed at patients in hemorrhagic shock

  
  

Why this matters

• 
  

  Traditional US prehospital resuscitation relied on crystalloid

  
  


• 
  

  ED and trauma care now prioritize early blood

  
  


• 
  

  Hemorrhage occurs before hospital arrival

  
  


• 
  

  Delays to definitive hemorrhage control are common

  
  


• 
  

  Earlier blood may improve survival

  
  

Supporting rationale

• 
  

  ATLS and trauma paradigms emphasize blood over fluid

  
  


• 
  

  National organizations support prehospital blood when feasible

  
  


• 
  

  EMS already manages high risk, time sensitive interventions

  
  

Evidence overview

• 
  

  Data are mixed and evolving

  
  
  
  
  • 
    

    COMBAT: no benefit

    
    
  
  
  • 
    

    PAMPer: mortality benefit

    
    
  
  
  • 
    

    RePHILL: no clear benefit

    
    
  
  
  
  


• 
  

  Signal toward benefit when transport time exceeds ~20 minutes

  
  


• 
  

  Urban systems still experience long delays due to traffic and geography

  
  


• 
  

  LA County median time to in hospital transfusion ~35 minutes

  
  

LA County program

• 
  

  ~2 years of planning before launch

  
  


• 
  

  Pilot began April 1

  
  


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  Partnerships:

  
  
  
  
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    LA County Fire

    
    
  
  
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    Compton Fire

    
    
  
  
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    Local trauma centers

    
    
  
  
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    San Diego Blood Bank

    
    
  
  
  
  


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  14 units of blood circulating in the field

  
  


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  Blood rotated back 14 days before expiration

  
  


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  Ultimately used at Harbor UCLA

  
  


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  Continuous temperature and safety monitoring

  
  

Indications used in LA County

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  Focused rollout

  
  


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  Trauma related hemorrhagic shock

  
  


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  Postpartum hemorrhage

  
  

Physiologic criteria:

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  SBP < 70

  
  


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  Or HR > 110 with SBP < 90

  
  


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  Shock index ≥ 1.2

  
  


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  Witnessed traumatic cardiac arrest

  
  

Products:

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  One unit whole blood preferred

  
  


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  Two units PRBCs if whole blood unavailable

  
  

Early experience

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  ~28 patients transfused at time of discussion

  
  


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  Evaluating:

  
  
  
  
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    Indications

    
    
  
  
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    Protocol adherence

    
    
  
  
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    Time to transfusion

    
    
  
  
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    Early outcomes

    
    
  
  
  
  


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  Too early for outcome conclusions

  
  

California collaboration

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  Multiple active programs:

  
  
  
  
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    Riverside (Corona Fire)

    
    
  
  
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    LA County

    
    
  
  
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    Ventura County

    
    
  
  
  
  


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  Additional programs planned:

  
  
  
  
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    Sacramento

    
    
  
  
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    San Bernardino

    
    
  
  
  
  


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  Programs meet monthly as CalDROP

  
  


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  Focus on shared learning and operational optimization

  
  

Barriers and concerns

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  Trauma surgeon concerns about blood supply

  
  


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  Need for system wide buy in

  
  


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  Community engagement

  
  


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  Patients who may decline transfusion

  
  


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  Women of childbearing age and alloimmunization risk

  
  


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  Risk of HDFN is extremely low

  
  


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  Clear communication with receiving hospitals is essential

  
  

Future direction

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  Rapid national expansion expected

  
  


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  Greatest benefit likely where transport delays exist

  
  


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  Prehospital Blood Transfusion Coalition active nationally

  
  


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  Major unresolved issue: reimbursement

  
  


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  Currently funded largely by fire departments

  
  


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  Sustainability depends on policy and payment reform

  
  

Take-Home Points

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  Hemorrhagic shock is best treated with blood, not crystalloid

  
  


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  Prehospital transfusion may benefit patients with prolonged transport times

  
  


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  Implementation requires strong partnerships with blood banks and trauma centers

  
  


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  Early data are promising, but patient selection remains critical

  
  


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  National collaboration is key to sustainability and future growth