What is the recommended dose of vasopressin (Vasopressin) for use in an intravenous (IV) pump, particularly in a critical care setting such as septic shock?

Vasopressin IV Pump Dosing for Septic Shock

Vasopressin should be administered as a continuous IV infusion at 0.01 units/minute for septic shock, titrated up by 0.005 units/minute every 10-15 minutes to a maximum of 0.03-0.04 units/minute, and never used as monotherapy—it must always be added to norepinephrine. 1, 2

Initial Dosing Protocol

• Start vasopressin at 0.01 units/minute when norepinephrine alone fails to maintain MAP ≥65 mmHg despite adequate fluid resuscitation (minimum 30 mL/kg crystalloids) 1, 2
• Titrate upward by 0.005 units/minute increments at 10-15 minute intervals until target blood pressure is achieved 1
• The standard maintenance dose is 0.03 units/minute—this is the dose recommended by the Surviving Sepsis Campaign guidelines for adding to norepinephrine 3, 2
• The FDA-approved dosing range for septic shock is 0.01 to 0.07 units/minute, though doses above 0.03-0.04 units/minute have limited safety data 1, 2

Preparation and Administration

• Dilute the 20 units/mL vial in normal saline (0.9% sodium chloride) or 5% dextrose in water (D5W) to either 0.1 units/mL or 1 unit/mL for IV administration 1
• Administer through central venous access whenever possible 2
• Discard unused diluted solution after 18 hours at room temperature or 24 hours under refrigeration 1
• Place an arterial catheter for continuous blood pressure monitoring as soon as practical 3, 2

Critical Dosing Ceiling and Safety Limits

Do not exceed 0.03-0.04 units/minute except as salvage therapy when all other vasopressors have failed. 2, 4 Higher doses are associated with:

• Marked decreases in mesenteric and renal blood flow causing potential ischemia 4
• Cardiac, digital, and splanchnic ischemia 1, 2
• The safe dose range for vasopressin in septic shock is narrow—animal studies demonstrate that moderately higher doses may induce organ ischemia while low doses do not impair blood flow to major vascular beds 4

Vasopressor Escalation Algorithm

When norepinephrine alone is insufficient:

1. Add vasopressin at 0.03 units/minute (not as monotherapy) to either raise MAP to target or decrease norepinephrine requirements 3, 2
2. If additional support is needed beyond norepinephrine plus vasopressin at 0.03 units/minute, add epinephrine as a third agent rather than increasing vasopressin dose 2
3. Consider dobutamine (up to 20 mcg/kg/min) if persistent hypoperfusion exists despite adequate vasopressor support, particularly with evidence of myocardial dysfunction 3, 2

Tapering Protocol

• After target blood pressure has been maintained for 8 hours without catecholamines, taper vasopressin by 0.005 units/minute every hour as tolerated to maintain target blood pressure 1
• Taper hydrocortisone (if used) when vasopressors are no longer required 3

Common Pitfalls to Avoid

• Never use vasopressin as the sole initial vasopressor—it must be added to norepinephrine, not used as monotherapy 2, 1
• Do not titrate vasopressin like other vasopressors—use a fixed low dose (0.03 units/minute) rather than escalating beyond 0.03-0.04 units/minute 2, 4
• Do not delay adding vasopressin if norepinephrine requirements remain elevated—the Surviving Sepsis Campaign suggests adding it when norepinephrine alone fails to achieve MAP targets 3, 2
• Monitor closely for signs of ischemia: digital ischemia, decreased urine output, rising lactate, elevated liver enzymes, or worsening organ dysfunction 1, 2
• Avoid using dopamine for renal protection—this is strongly discouraged and has no benefit 3, 2