Fever and Hypotension in a Patient on Furosemide
A 74-year-old man is brought to the emergency department by his daughter. He has a 3-day history of productive cough with yellow sputum, fever to 38.9 °C, and increasing confusion since this morning. Past history: hypertension, heart failure with reduced ejection fraction (last echo LVEF 32%), type 2 diabetes. Current medications: furosemide 80 mg daily, bisoprolol 5 mg daily, perindopril 5 mg daily, metformin 1000 mg twice daily. On arrival: drowsy but rousable, BP 82/48 mmHg, HR 112/min, SpO2 88% on room air, respiratory rate 28/min, temperature 38.7 °C. Capillary refill 4 s. Chest exam shows right basal crackles. Blood glucose 9.8 mmol/L. Serum creatinine 168 µmol/L (baseline 104 µmol/L), lactate 4.1 mmol/L. Chest X-ray shows right lower lobe consolidation.
1. Classify this patient's hemodynamic state and explain which findings support sepsis with hypoperfusion rather than simple dehydration or cardiogenic deterioration.
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This is septic shock with tissue hypoperfusion. Supporting reasoning:
- Infection source is clear (right lower lobe pneumonia, fever, purulent sputum), so sepsis is the working diagnosis.
- Hypotension (BP 82/48) plus lactate 4.1 mmol/L and prolonged capillary refill (4 s) indicate hypoperfusion; under the surviving-sepsis framework, vasopressor-requiring hypotension with lactate >2 defines septic shock.
- Not primarily dehydration: although furosemide and fever predispose to volume loss, the lactate elevation and altered mentation point to impaired perfusion beyond simple hypovolemia; both can coexist.
- Not primarily cardiogenic: no new chest pain, no jugular venous distension or pulmonary edema described beyond the consolidated lobe; the focal consolidation and fever direct attention to sepsis. Beta-blocker use may blunt tachycardia (HR 112 is already high despite bisoprolol).
- Confusion in an elderly patient is an organ dysfunction marker (qSOFA/mental status), reinforcing severity.
2. Outline your immediate management priorities in the first hour, naming specific actions and the reasoning behind each.
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First hour (sepsis bundle):
- Oxygen to target SpO2 94–98% (88% on room air is inadequate); consider high-flow or non-invasive support if work of breathing increases.
- Blood cultures before antibiotics if this does not delay therapy >45 min, plus sputum, urine, and lactate.
- Empiric broad-spectrum antibiotics covering community-acquired pneumonia (e.g., a beta-lactam plus macrolide, or a respiratory fluoroquinolone), adjusted for local resistance and renal function.
- Crystalloid fluid resuscitation - typically 30 mL/kg balanced crystalloid started promptly, reassessing after each bolus for signs of fluid intolerance (given LVEF 32%, watch for pulmonary edema, rising JVP, worsening oxygenation).
- Vasopressors (norepinephrine) if MAP remains <65 mmHg after initial fluids; do not delay while awaiting central access (peripheral initiation is acceptable short-term).
- Hold furosemide and perindopril during the acute hypoperfusion phase; perindopril worsens hypotension and renal perfusion, furosemide worsens hypovolemia. Continue beta-blocker cautiously or hold if bradycardic/hypotensive.
- Metformin: hold during acute illness with renal impairment (creatinine 168 µmol/L) to reduce lactic acidosis risk; monitor glucose.
- Reassess perfusion (lactate clearance, urine output, mentation, capillary refill) and escalate if no improvement.
3. The patient's creatinine rose from 104 to 168 µmol/L. How do you interpret this and what adjustments are needed?
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Interpretation: This is acute kidney injury, most consistent with sepsis-associated AKI plus prerenal contribution (fever, poor intake, furosemide, ACE inhibitor). It is not necessarily intrinsic renal disease at this stage, but must be monitored.
- Staging: a rise of ~1.6× baseline is KDIGO stage 1 (1.5–1.9× baseline).
- Contributors to address: stop nephrotoxic and hypotensive agents (perindopril, furosemide, metformin), restore perfusion with fluids and vasopressors, avoid additional nephrotoxins (NSAIDs, contrast if avoidable).
- Drug dosing: renally adjust antibiotics and any other medications; avoid drugs requiring reliable renal clearance where alternatives exist.
- Monitoring: strict fluid balance, hourly urine output, daily creatinine and electrolytes (watch for hyperkalemia), and reassess after resuscitation. If oliguria persists despite adequate perfusion, reconsider fluid status and look for other causes.