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We go over the essential and complex topic of vasopressors in the ED.
Hosts:
Brian Gilberti, MD
Catherine Jamin, MD
Show Notes
Introduction
- Host: Brian Gilberti, MD
- Guest: Catherine Jamin, MD
- Associate professor of Emergency Medicine at NYU Langone Health
- Vice Chair of Operations
- Triple-boarded in Emergency Medicine, Internal Medicine, and Critical Care Medicine
- Topic: Vasopressors: Essential agents for supporting critically ill patients in the ED
What Are Vasopressors and When to Use Them
- Two primary mechanisms to increase blood pressure:
- Increasing systemic vascular resistance via vasoconstriction
- Increasing cardiac output via augmenting inotropy and chronotropy
- Indicators for vasopressor use:
-
- MAP <65, systolic BP <90, or significant drop from baseline BP
- Signs of organ dysfunction like altered mental status, decreased urine output, elevated lactate
- Fluid resuscitation either ineffective or contraindicated (e.g., in CHF patients)
Commonly Used Vasopressors in the ED
- Norepinephrine
- Epinephrine
- Vasopressin
- Phenylephrine
Norepinephrine
- Mechanism: Stimulates alpha-1 (vasoconstriction) and beta-1 receptors (increases inotropy & chronotropy)
- Starting Dose: 10 mcg/min, titrate to MAP >65
- Max Dose: No strict limit but usually add a 2nd pressor at 15-20 mcg/min
- Situational Preference: First-line for most cases of shock (septic, undifferentiated, hypovolemic, cardiogenic)
- Pros: Can be infused peripherally via large bore IV
Vasopressin
- Mechanism: Activates V1a receptors causing vasoconstriction
- Dose: Fixed, non-titratable dose of 0.04 units/min
- Situational Preference: Second-line in septic shock
- Concerns: Potential for peripheral ischemia
Phenylephrine
- Mechanism: Stimulates alpha-1 receptors causing vasoconstriction
- Starting Dose: 100 mcg/min, titrate to MAP >65
- Situational Preference: High cardiac output states, tachyarrhythmias, peri-intubation
- Concerns: Increases afterload, can worsen low cardiac output states
Epinephrine
- Mechanism: Stimulates alpha-1, beta-1 and beta-2 receptors
- Starting Dose: 5-10 mcg/min, titrate to MAP >65
- Situational Preference: Anaphylactic shock, septic cardiomyopathy
- Limitations: Can induce tachycardia, may elevate lactate levels
Escalation Strategy in Refractory Shock
- Norepinephrine -> Vasopressin (with stress dose steroids) -> Epinephrine
- Consider POCUS, lactate, central venous saturation, and acid-base status
Peripheral Pressors
- Can safely be administered peripherally via large bore IVs in proximal upper extremity
- Sites: Cephalic or basilic veins
- Adverse Events: Low at 1.8% based on meta-analysis
- Actions in case of extravasation: Phentolamine injection, nitroglycerin paste
Push-Dose Pressors
- Primarily Phenylephrine (peri-intubation, during procedures)
- Also Epinephrine for peri-code situations
- Doses: Epi – 5-20 mcg every 2-5 min
Take-Home Points
- Most used medications are going to be norepinephrine, vasopressin, phenylephrine, and epinephrine.
- Consider these medications if there are signs of end-organ dysfunction, there is a considerable delta in baseline BP, systolic is less than 90 and/or MAP is less than 65
- Norepinephrine is a good pressor for a lot of the situations that we encounter in the emergency department, such as septic shock, undifferentiated shock and hypovolemic shock.
- Vasopressin is commonly the second we reach for in most of these scenarios
- Epinephrine will be first for anaphylactic shock and may be the third agent in septic shock
- Think about phenylephrine in high-output states (patients with tachydysrhythmias), or with AS, though be cautious in patient with low cardiac output
- The benefits outweigh risks for peripheral pressors in situations where you promptly have to increase blood pressure while you work on central access
- Push-dose pressures can help you in a peritinbatuion or pericode situation because it is going to be one of the fastest ways we can boost BP while we work on other measures to stabilize the patient