What is the protocol for IV (intravenous) frusemide administration?

IV Furosemide Administration Protocol

For acute fluid overload or pulmonary edema, start with furosemide 20-40 mg IV push over 1-2 minutes, with the dose determined by prior diuretic exposure and clinical severity. 1

Initial Dosing Strategy

Standard Initial Dose

• Diuretic-naïve patients or mild fluid overload: 20-40 mg IV push over 1-2 minutes 1
• Patients on chronic oral diuretics: Use IV dose at least equivalent to their oral dose 2
• Acute pulmonary edema: 40 mg IV push over 1-2 minutes as initial dose 1

Critical Pre-Administration Requirements

• Systolic blood pressure must be ≥90-100 mmHg before administering furosemide—giving it to hypotensive patients worsens hypoperfusion and can precipitate cardiogenic shock 2
• Exclude severe hyponatremia (sodium <120-125 mmol/L), which is an absolute contraindication 2
• Exclude anuria, which is an absolute contraindication 2
• Verify absence of marked hypovolemia before administration 2

Dose Escalation Protocol

Timing and Increments

• If inadequate response after initial dose: Give another dose 2 hours later or increase by 20 mg 1
• For acute pulmonary edema: If no satisfactory response within 1 hour, increase to 80 mg IV push over 1-2 minutes 1
• Continue escalating by 20 mg increments every 2 hours until desired diuretic effect is achieved 2

Maximum Dosing Limits

• First 6 hours: Total dose should not exceed 100 mg 2
• First 24 hours: Total dose should not exceed 240 mg 2
• Daily maximum in cirrhosis: 160 mg/day (exceeding this indicates diuretic resistance) 3

Administration Methods

Bolus vs. Continuous Infusion

• Bolus therapy is preferred initially for most acute situations 2, 4
• Continuous infusion may be considered after initial bolus in patients with severe volume overload 2
• Continuous infusion dosing: Start at 3-5 mg/hour, double hourly until adequate diuresis (>0.5 mL/kg/hour), maximum rate 4 mg/min 2, 1
• Continuous infusion is more efficient: Requires significantly less total furosemide dose (9.2 mg/h vs 24.1 mg/h for bolus) to achieve same diuresis 5

Preparation for High-Dose Infusion

• Add furosemide to NS, LR, or D5W after adjusting pH to >5.5 1
• Administer at rate not exceeding 4 mg/min to prevent ototoxicity 1
• Never mix with acidic solutions (labetalol, ciprofloxacin, amrinone, milrinone) as this causes precipitation 1

Monitoring Requirements

Immediate Monitoring (First 6 Hours)

• Place bladder catheter to monitor hourly urine output and rapidly assess treatment response 2
• Blood pressure every 15-30 minutes in the first 2 hours 2
• Target urine output: >0.5 mL/kg/hour indicates adequate response 2

Short-Term Monitoring (24 Hours)

• Check electrolytes within 6-24 hours: Particularly sodium, potassium, and chloride 2, 6
• Monitor renal function within 24 hours: Creatinine and estimated GFR 2
• Daily weights: Target 0.5-1.0 kg loss per day depending on presence of peripheral edema 2

Expected Response Timeline

• Peak effect occurs within 1-1.5 hours after IV administration 2, 7
• Duration of action: 6-8 hours 2
• Median urine output increase: 590 mL in first 6 hours, but highly variable (range 290-1111 mL) 6

Concurrent Therapy

For Acute Pulmonary Edema

• IV nitroglycerin is superior to high-dose furosemide alone and should be started immediately alongside furosemide 2
• Combination of high-dose IV nitrates with low-dose furosemide is more effective than high-dose diuretic alone 2
• Non-invasive positive pressure ventilation (CPAP/BiPAP) should be applied if respiratory rate >20 breaths/min and SBP >85 mmHg 2

For Diuretic Resistance

• Add thiazide diuretic (hydrochlorothiazide 25 mg PO) rather than escalating furosemide beyond 160 mg/day 2
• Add aldosterone antagonist (spironolactone 25-50 mg PO) if congestion persists after 24-48 hours 2
• Sequential nephron blockade is more effective than monotherapy escalation 2

Absolute Contraindications and When to Stop Immediately

Stop Furosemide If:

• Systolic blood pressure drops <90 mmHg without circulatory support 2
• Severe hyponatremia develops (sodium <120-125 mmol/L) 2
• Severe hypokalemia occurs (<3 mmol/L) 2
• Anuria develops 2
• Progressive renal failure or acute kidney injury worsens 2
• Marked hypovolemia with signs of decreased skin turgor, hypotension, tachycardia 2

Special Populations

Pediatric Dosing

• Initial dose: 1 mg/kg IV given slowly under close medical supervision 1
• Dose escalation: Increase by 1 mg/kg not sooner than 2 hours after previous dose 1
• Maximum dose: 6 mg/kg/day (not to be exceeded) 1
• Premature infants: Maximum 1 mg/kg/day 1

Geriatric Patients

• Start at low end of dosing range (20 mg IV) with cautious titration 1

Cirrhosis with Ascites

• Oral administration is preferred over IV to avoid acute GFR reduction 2
• If IV required: Start with 40 mg IV, combined with spironolactone 100 mg 3
• Maintain 100:40 spironolactone-to-furosemide ratio to optimize natriuresis while minimizing electrolyte disturbances 2

Common Pitfalls to Avoid

• Never give furosemide expecting it to improve hemodynamics in hypotensive patients—it worsens hypoperfusion 2
• Do not use furosemide to prevent or treat acute kidney injury—only for managing volume overload that complicates AKI 2
• Avoid evening doses—they cause nocturia and poor adherence without improving outcomes 2
• Do not escalate beyond 160 mg/day without adding second diuretic—this hits ceiling effect without additional benefit 2
• Infusions >4 mg/min risk ototoxicity—always administer slowly 1