11.4 Febrile Neutropenia, Sepsis & Vesicant Extravasation

Hematologic & Cardiovascular Emergencies

Hematologic and cardiovascular emergencies in oncology present acute threats to survival, driven by treatment-induced bone marrow suppression, fulminant systemic infection, or destructive vascular drug extravasation. Neutropenic Fever (NF), Oncologic Sepsis, and Chemotherapy Vesicant Extravasation represent high-stakes clinical scenarios requiring standardized, evidence-based Advanced Practice Registered Nurse (APRN) emergency management.

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1. Neutropenic Fever: Diagnostic Criteria & ANC Calculation

Neutropenic fever is a medical emergency. Due to profound neutropenia, the normal inflammatory response is severely blunted; fever is frequently the only early manifestation of overwhelming bacterial infection.

IDSA / ASCO Diagnostic Criteria

• Fever Criteria: A single oral temperature $\ge 38.3^\circ\text{C}$ ($101.0^\circ\text{F}$) OR a sustained temperature $\ge 38.0^\circ\text{C}$ ($100.4^\circ\text{F}$) over a 1-hour period.
• Neutropenia Criteria: An Absolute Neutrophil Count (ANC) $< 500/\mu\text{L}$, or an ANC $< 1000/\mu\text{L}$ with a predicted decline to $< 500/\mu\text{L}$ over the subsequent 48 hours.

ANC Calculation Formula

$\text{ANC (/}\mu\text{L)} = \text{WBC (/}\mu\text{L)} \times \left( \frac{\%\text{Segmented Neutrophils} + \%\text{Bands}}{100} \right)$

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2. Risk Stratification: MASCC Risk Index Score

The Multinational Association for Supportive Care in Cancer (MASCC) Risk Index stratifies patients with neutropenic fever into low-risk and high-risk categories to determine treatment setting.

MASCC Scoring Criteria

Risk Classification & Clinical Triage

• MASCC Score $\ge 21$ (Low Risk): Low risk of severe septic complications ($<5%$ mortality). Note that 26 is the maximum attainable score, not the cut point — a frequent exam trap. Eligible for outpatient oral empiric antibiotic therapy (e.g., Ciprofloxacin 500 mg PO Q12H + Amoxicillin-Clavulanate 875 mg PO Q12H) provided close 24-hour telephone follow-up is ensured.
• MASCC Score $< 21$ (High Risk): High risk of severe complications and mortality. Mandates inpatient hospital admission for intravenous broad-spectrum anti-pseudomonal monotherapy.

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3. Empiric Antimicrobial Protocol for Neutropenic Fever

Neutropenic Fever Identified (Temp >= 38.3°C + ANC < 500)
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  ├─► Emergency Diagnostic Workup (< 15 mins): 2 Sets Blood Cultures (1 Peripheral + 1 Central Line Lumen)
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  ├─► DOOR-TO-ANTIBIOTIC TIME < 60 MINUTES
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  ├─► First-Line Empiric IV Monotherapy (Anti-pseudomonal Beta-lactam):
  │     ├─► Cefepime 2 g IV Q8H  OR  Piperacillin-Tazobactam 4.5 g IV Q6H  OR  Meropenem 1 g IV Q8H
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  └─► Assess Specific Indications for Empiric Vancomycin:
        └─► Septic Shock, CLABSI, MRSA Colonization, Skin/Soft Tissue Infection, Severe Mucositis

Door-to-Antibiotic Emergency Standard

• Empiric broad-spectrum IV antibiotics must be administered within 60 minutes of arrival/fever identification ("door-to-antibiotic time $< 60\text{ min}$").
• Obtain 2 sets of blood cultures prior to antibiotic infusion (1 peripheral set + 1 set from each lumen of central venous access devices).

First-Line Empiric Regimens

• IV Anti-Pseudomonal Monotherapy: Cefepime 2 g IV Q8H, Piperacillin-Tazobactam (Zosyn) 4.5 g IV Q6H, or Meropenem 1 g IV Q8H.
• Indications for Adding Empiric Vancomycin: Hemodynamic instability or septic shock; suspected central line-associated bloodstream infection (CLABSI); known MRSA colonization; skin/soft tissue infection; severe grade 3–4 mucositis; radiologic pneumonia.

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4. Sepsis & Septic Shock in Oncology

Oncology patients in septic shock exhibit severe dysregulated host response, refractory hypotension, and microvascular hypoperfusion.

Surviving Sepsis Campaign 1-Hour Bundle

1. Measure serum lactate level; remeasure if initial lactate $>2\text{ mmol/L}$.
2. Obtain blood cultures prior to antibiotic administration.
3. Administer broad-spectrum anti-pseudomonal IV antibiotics.
4. Rapidly administer $30\text{ mL/kg}$ crystalloid bolus for hypotension or lactate $\ge 4\text{ mmol/L}$.
5. Apply vasopressors (Norepinephrine as first-line choice) during or after fluid resuscitation to maintain Mean Arterial Pressure (MAP) $\ge 65\text{ mmHg}$.

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5. Chemotherapy Vesicant Extravasation Management

Extravasation is the accidental infiltration of a chemotherapy drug into surrounding perivascular tissues. Agents are classified based on tissue toxicity potential:

• Vesicant: Causes severe, progressive tissue destruction, blistering, sloughing, tissue necrosis, and loss of function.
• Irritant: Causes localized pain, burning, inflammation, or phlebitis along the vein, but without tissue necrosis.

Major Vesicant Drug Classes

• Anthracyclines: Doxorubicin, Daunorubicin, Epirubicin, Idarubicin (DNA binding, free radical generation, progressive tissue necrosis).
• Vinca Alkaloids: Vincristine, Vinblastine, Vinorelbine (microtubule inhibitors).
• Other Vesicants: Mechlorethamine, Dactinomycin, Mitomycin-C, Trabectedin, and Cisplatin at concentrations $>0.5\text{ mg/mL}$. The taxanes (paclitaxel, docetaxel) and etoposide are classified by ONS as irritants with vesicant potential — they can blister or cause superficial exfoliation with large-volume extravasation but do not reliably produce full-thickness necrosis.

Universal Extravasation Emergency Protocol

1. IMMEDIATELY STOP the chemotherapy infusion upon suspicion (pain, burning, swelling, resistance).
2. Leave the cannula/needle in place. Attach a syringe and aspirate residual drug from the catheter. Do NOT flush the line!
3. Remove the cannula/needle. Elevate the affected extremity above heart level.
4. Initiate class-specific thermal application and specific antidote administration.

Class-Specific Thermal & Antidote Matrix