Vasopressin Dosing in Septic and Distributive Shock
For septic shock, the recommended starting dose of vasopressin is 0.01 units/minute, which can be titrated up by 0.005 units/minute every 10-15 minutes until target blood pressure is reached, with a maximum dose of 0.03 units/minute. 1
Dosing Guidelines
The FDA-approved vasopressin dosing protocol for septic shock includes:
- Starting dose: 0.01 units/minute 1
- Titration: Increase by 0.005 units/minute at 10-15 minute intervals 1
- Maximum dose: 0.03 units/minute as indicated in critical care guidelines 2
- Post-cardiotomy shock: Higher starting dose of 0.03 units/minute 1
Administration Considerations
- Vasopressin should be diluted in normal saline (0.9% sodium chloride) or 5% dextrose in water (D5W) prior to intravenous administration 1
- Discard unused diluted solution after 18 hours at room temperature or 24 hours under refrigeration 1
- Limited data exists for doses above 0.07 units/minute in septic shock, with adverse reactions expected to increase at higher doses 1
Weaning Protocol
After target blood pressure has been maintained for 8 hours without catecholamines:
- Taper vasopressin by 0.005 units/minute every hour as tolerated 1
- Continue to monitor blood pressure during the weaning process
Positioning in Shock Management
- Norepinephrine remains the first-choice vasopressor for shock management 2
- Vasopressin is typically used as an adjunct to catecholamines to support blood pressure in refractory septic shock 3
- Vasopressin infusion at 0.01 to 0.03 units/minute increases plasma vasopressin levels to those observed in patients with other causes of hypotension 4
Clinical Response and Outcomes
- Vasopressin response (defined as a reduction in catecholamine requirements) is associated with improved clinical trajectory in septic shock patients 5
- Vasopressin may be a good first option in patients with refractory septic shock when norepinephrine alone is insufficient 6
- Vasopressin use may be associated with less need for renal replacement therapy compared to norepinephrine alone (25.4% vs 35.3%) 7
Important Caveats
- Infusions exceeding 0.04 units/minute may lead to adverse vasoconstriction-mediated events 4
- Norepinephrine doses above 1 μg/kg/min are associated with mortality rates over 80%, suggesting the need to implement adjunctive strategies like vasopressin before reaching this threshold 6
- Monitor patients closely for signs of myocardial dysfunction, ischemia, and other complications, especially in those with cardiac conditions 2