Vasopressor Therapy in Severe Hypotension

Initial Management

The American College of Critical Care Medicine recommends initiating norepinephrine as the first-line vasopressor to achieve a mean arterial pressure (MAP) ≥65 mmHg in patients with severe hypotension who fail to respond to initial fluid bolus 1, 2, 3
Approximately 50% of hypotensive patients are not fluid-responsive, and continued fluids risk pulmonary edema and worsening outcomes, prompting termination of further fluid resuscitation immediately 1
A blood pressure of 60/40 represents life-threatening hypotension requiring urgent vasopressor support 4

The Surviving Sepsis Campaign guidelines mandate vasopressor initiation when MAP remains <65 mmHg despite adequate fluid resuscitation 5, 2
Norepinephrine is recommended as the first-choice vasopressor by all major critical care societies for distributive, septic, and most forms of shock 1, 2, 3
Start norepinephrine at 0.02 mcg/kg/min and titrate rapidly to achieve MAP ≥65 mmHg 1, 2

Place an arterial line as soon as practical for continuous blood pressure monitoring in all patients requiring vasopressors 2
Position the patient supine to improve MAP compared to semi-sitting positions 3
Monitor for signs of adequate perfusion, including improved mental status, capillary refill <3 seconds, urine output >0.5 mL/kg/hr, and lactate clearance 1, 2, 3

For anaphylactic shock, administer intramuscular epinephrine 0.3-0.5 mg immediately in addition to IV vasopressors and fluids 3
For traumatic hemorrhagic shock, norepinephrine is recommended only if systolic BP <80 mmHg persists despite restricted volume replacement 4
For severe traumatic brain injury, target MAP ≥80 mmHg to ensure adequate cerebral perfusion pressure 1