PLEASE NOTE THAT THERE ARE 2 PROTOCOLS
- the management of IV extravasations (leakage of an IV fluid out of a vein and into surrounding tissue)
- for the management of extravasation due to vasoactive medications (eg. dobutamine, dopamine, epinephrine, norepinephrine, phenylephrine)
- competitively blocks alpha - adrenergic receptors, thereby producing brief antagonism of circulating epinephrine and norepinephrine
- this causes relaxation of vascular smooth muscle and the development of a hyperemic response (increase of blood flow)
- phentolamine also stimulates beta adrenergic receptors and produces a positive inotropic (force of contraction) and chronotropic (rate) effect on the heart
- CDV: hypotension, tachycardia, cardiac arrhythmias
- GI: vomiting, diarrhea,
- other: nasal congestion
- use with caution in patients with renal impairment or gastritis
- Add 1.8 mL sterile water to 0.2 mL of 5 mg/mL phentolamine
FINAL CONCENTRATION =1 mg/2mL =0.5 mg/mL
- infiltrate the area of extravasation with multiple small injections of the 0.5 mg/mL solution
- use a 27g or smaller needle and change needles between each skin entry
- do not inject a volume such that swelling of the area occurs
- it has been suggested that a dose of 0.1 mg/kg (ie. 0.2 mL/kg of the 0.5 mg/mL solution) not be exceeded
- blanching should reverse immediately
- monitor site of extravasation closely; additional injections of phentolamine may be necessary
Treatment of Overdose
- main clinical manifestations are hypotension, tachycardia, cardiac stimulation, and arrhythmias
- norepinephrine (initial dose: 0.05 to 0.1 mcg/kg/min, then cautiously titrated in a continuous IV infusion to a maximum of 1 to 2 mcg/kg/min), is the pharmacological antagonist
- do NOT use ephinephrine; this may cause a further fall in blood pressure
- 5 mg / mL, 1 mL ampoule
- kept in refrigerator
- trade name is "Rogitine(R)"
- "Rogitine" package insert, CIBA, Missauga, Ontario (P4824943)
- Flemmer L and Chan JSL : A pediatric protocol for management of extravasation injuries, Pediatric Nursing 1993; 19 : 355-8, 424.
- "Phentolamine" in Taketomo CK, Hodding JH and Kraus DM : Pediatric Dosing Handbook, 1998-99, 5th Edition, American Pharmaceutical Association.
- "Phentolamine" in American Hospital Formulary Service, American Society of Health System Pharmacist, Bethesda,MD,1996.