Pressor Protocol for Acute Hypotension in the Cath Lab

Initial Management

The American College of Cardiology recommends norepinephrine as the first-line vasopressor for acute hypotension in the cath lab, started at 0.1-0.5 mcg/kg/min via peripheral IV if central access is unavailable, targeting a mean arterial pressure of 65 mmHg 1
Before initiating any vasopressor, address hypovolemia with fluid boluses to optimize cardiac output, as vasoconstriction in hypovolemic patients causes severe organ hypoperfusion despite "normal" blood pressure 1

Central venous access is strongly preferred to minimize extravasation risk and tissue necrosis 1, 2
If central access is unavailable or delayed during the acute cath lab scenario, peripheral IV administration can be used temporarily with strict monitoring 3, 1

Add vasopressin at 0.03 units/minute when norepinephrine reaches 0.25 mcg/kg/min and hypotension persists, rather than continuing to escalate norepinephrine alone 4, 1, 2
Never use vasopressin as monotherapy—it must be added to norepinephrine 2

Add epinephrine at 0.1-0.5 mcg/kg/min when norepinephrine plus vasopressin fail to achieve target MAP 1, 2
Epinephrine increases risk of serious cardiac arrhythmias, particularly ventricular arrhythmias (RR 0.35; 95% CI 0.19-0.66 compared to norepinephrine alone) 2

Add dobutamine at 2.5-20 mcg/kg/min if persistent hypoperfusion exists despite adequate MAP and vasopressor therapy, particularly when myocardial dysfunction is evident 5, 1, 2

Blood pressure should be monitored every 5-15 minutes during titration 3, 1
Continuous arterial monitoring via arterial catheter should be done as soon as practical 4, 1
Tissue perfusion markers such as urine output, lactate, mental status, and capillary refill should be monitored 1, 2
ECG monitoring for arrhythmias, especially with epinephrine, is recommended 2