Vasopressors
Background
The goal of vasopressor use is to reach critical organ perfusion pressure. Estimated required mean arterial pressures (MAP) are listed below. It is generally safe to aim for a goal map of 65 mmHg. Vasopressors also promote increased venous return.
IV Vasopressor have not been shown to be unsafe when used peripherally[4] If running peripherally perform frequent site check via institutional protocol. [5]
Norepinephrine
Dopamine
Dobutamine
Phenylephrine
Vasopressin
Epinephrine
Indication
- Anaphylaxis
Primary Receptor
- β1
- α1
- β2
Relative Effects
- ↑↑↑HR
- ↑↑↑SV
- ↑↑↑SVR
- Bronchodilation (β2)
Dosing
- Dose-dependent effects:
- 1-10 mcg/min - increase HR and SV
- 10-20 mcg/min - increase SVR
Rate of Titration
- Q2-5 min
Adverse Effects
- Tachyarrhythmias
- Myocardial ischemia
- ↑Serum lactate
- Splanchnic ischemia
Notes
- ↑lactate occurs primarily from ↑glycolysis/glycogenolysis within skeletal muscles not tissue hypoperfusion
- Use with caution in pts with CAD
- However clinical trials have not demonstrated worsened outcomes
Milrinone
Indication
low cardiac output states due to impaired myocardial contractility
Primary Receptor
- PDE-3 inhibitor
Relative Effects
- ↑HR
- ↑↑↑SV
- ↓SVR
Dosing
- Normal renal function:
0.25 - 0.75 mcg/kg/min
- Creatinine clearance < 50mL/min, reduce infusion rate
Rate of Titration
- Q2H; slower titration rate if renal insufficiency
Adverse Effects
- Tachyarrhythmias
- Hypotension
- Myocardial ischemia
Notes
- Can use as alternative to dobutamine in pts with cardiogenic shock and on b-blockers
- Causes pulmonary vasodilation, may be good choice in pts with RV failure
- ↑cAMP in cardiac myocytes and vascular smooth muscle, thereby ↑HR and ↑SV while decreasing ↓SVR
- Use with caution in pt with renal failure and hypovolemia
Push Dose Pressors
- Use when need temporary BP or CO boost
- Post-intubation hypotension
- Propofol-induced hypotension
- A-fib w/ hypotension
- Easier to convert well-perfused heart
Epinephrine
- Mix 9mL of NS with 1mL of 1:10,000 epi
- Now have 10mL of 10mcg/mL
- Use 0.5-2mL q2-5min (similar to epi drip)
- Same as 2% lido with epi
- Ok to give peripherally
- Now have 10mL of 10mcg/mL
- Onset - 1min
- Duration - 5-10min
Phenylephrine
- Pure alpha (no effect on heart)
- Place 1mL of 10mg/mL vial in 100mL NS
- Now have 100mcg/mL
- Draw up 10mL
- Use 0.5-2mL q2-5min (50-200mcg)
- Onset - 1min
- Duration - 20min
Source
- ↑ Plöchl, W, D J Cook, T A Orszulak, and R C Daly. 1998. Critical cerebral perfusion pressure during tepid heart operations in dogs. The Annals of thoracic surgery, no. 1. http://www.ncbi.nlm.nih.gov/pubmed/9692450
- ↑ Emcrit Vasopressor basics http://emcrit.org/podcasts/vasopressor-basics/
- ↑ Bellomo, Rinaldo, Li Wan, and Clive May. 2008. Vasoactive drugs and acute kidney injury. Critical care medicine, no. 4 Suppl. doi:10.1097/CCM.0b013e318169167f. http://www.ncbi.nlm.nih.gov/pubmed/18382191.
- ↑ Ricard JD. et al. Central or peripheral catheters for initial venous access of ICU patients: a randomized controlled trial. Crit Care Med. 2013 Sep;41(9):2108-15
- ↑ Chen J. et al. Extravasation injury associated with low-dose dopamine.. Ann Pharmacother. 1998 May;32(5):545-8
- EmCrit Podcast 6