Vasopressin

General

• Type: Vasopressors
• Dosage Forms:
• Common Trade Names:

Adult Dosing

Dosing

• 0.01-0.04 units/min (typically 0.03 or 0.04 U/min)

Rate of Titration

• Fixed dose (do not titrate)

Pediatric Dosing

0.0002–0.008 U/kg/min have been studied although no current consensus on dosage

Special Populations

• Pregnancy Rating: C
• Lactation:
• Renal Dosing
  • Adult
  • Pediatric
• Hepatic Dosing
  • Adult
  • Pediatric

Contraindications

• Allergy to class/drug

Adverse Reactions

• Bradycardia
• Limb ischemia
• Myocardial ischemia
• Splanchnic ischemia

Pharmacology

• Half-life: <20 minutes
• Metabolism: liver, kidney extensively; CYP450: unknown
• Excretion: urine (5-6% unchanged)
• Mechanism of Action: "directly stimulates V1 and V2 receptors, resulting in vasoconstriction and antidiuresis"

Primary Receptor

• V1

Relative Effects

• ↑SVR
• ↓HR

Notes

• Adverse effects are dose-dependent
• Acts on V1 receptors leading to ↑vasoconstriction and
• ↑sensitivity to catecholamines in patients with shock
• in contrast to catecholamine vasopressors (e.g. epinephrine, norepinephrine), vasopressin does not lose efficacy at low pH

Indication

• Adjunct for septic shock VASST trial
  • no difference in mortality when vasopressin was added as second line pressor compared to norepinephrine
  • subgroup analysis found that patients with less severe septic shock did better with vasopressin

See Also

http://www.atsjournals.org/doi/abs/10.1164/rccm.201006-0972CI?url_ver=Z39.88-2003&rfr_id=ori:rid:crossref.org&rfr_dat=cr_pub%3dpubmed#readcube-epdf