Vasopressin Discontinuation Strategy
Discontinue vasopressin AFTER weaning norepinephrine to low doses (typically <5-10 mcg/min), not before, as stopping vasopressin first significantly increases the risk of rebound hypotension.
Evidence-Based Weaning Sequence
The Surviving Sepsis Campaign guidelines 1 establish vasopressin (0.03 units/min) as an adjunct to norepinephrine for raising MAP or decreasing norepinephrine requirements, but do not specify discontinuation order. However, the guideline explicitly states that vasopressin withdrawal should occur after norepinephrine weaning, as performed in landmark trials (VASST and VANISH), since withdrawing vasopressin first was associated with more hemodynamic instability 2.
Clinical Algorithm for Vasopressor Weaning:
Begin weaning norepinephrine first once hemodynamic stability is achieved (MAP ≥65 mmHg, adequate tissue perfusion markers)
Continue vasopressin at 0.03 units/min (fixed dose) while titrating norepinephrine down
Discontinue vasopressin only after norepinephrine is reduced to low maintenance doses
Monitor closely for 24 hours after stopping either agent, as hypotension risk peaks during this period
Supporting Research Evidence
Multiple studies demonstrate the hazards of stopping vasopressin first:
Older retrospective data showed discontinuing vasopressin before norepinephrine resulted in hypotension rates of 56% vs 16% (RR 3.6-5.9) 3, 4
Meta-analysis (2020) found discontinuing vasopressin first increased hypotension incidence (OR 0.3,95% CI 0.10-0.86) 5
Most recent 2025 study using propensity score weighting found no significant difference in hypotension rates (19% vs 21%, p=0.59) when accounting for baseline imbalances and end doses 6
Important Nuance:
The most recent high-quality study 6 challenges older findings by demonstrating that when vasopressor end doses are properly matched and baseline characteristics balanced, the order of discontinuation may matter less than previously thought. However, this study still showed a trend toward more hypotension with vasopressin-first discontinuation, and the guideline-recommended approach remains to wean norepinephrine first 2.
Practical Considerations
Common pitfalls to avoid:
- Don't abruptly stop vasopressin - this creates sudden loss of non-adrenergic vasoconstriction
- Don't maintain supra-therapeutic vasopressor doses out of fear - wean as soon as hemodynamically stable 2
- Don't ignore occult volume depletion - correct hypovolemia before attributing hypotension to vasopressor weaning 7
Target norepinephrine dose for vasopressin discontinuation:
While no absolute threshold exists, aim for norepinephrine <5-10 mcg/min before stopping vasopressin. The FDA label 7 notes maintenance doses of 2-4 mcg/min are typical, suggesting vasopressin can be discontinued once approaching this range.
Monitoring requirements:
- Arterial line monitoring essential 1
- Serial lactate, urine output, mental status
- Watch for hypotension (MAP <60 mmHg) requiring ≥25% increase in remaining vasopressor or fluid bolus 6
No Impact on Mortality
Importantly, the order of vasopressor discontinuation does not affect mortality or ICU length of stay 6, 5, 3, 8. The primary concern is avoiding hemodynamic instability during the recovery phase, not survival outcomes. This means the conservative approach of weaning norepinephrine first carries minimal downside risk while potentially preventing rebound hypotension episodes.