Chapter 28 ■ Management of Extravasation Injuries 153

iii. Hyaluronidase: Dispersing agent effective in

extravasations involving calcium, parenteral

alimentation fluids, antibiotics, sodium bicarbonate, etc. Although standard reference manuals state

that hyaluronidase is not recommended for treatment of vasopressor extravasation injury, there

have been reports of successful treatment of such

extravasations with a combination of hyaluronidase

and saline irrigations, as described above (2,12).

Mechanism of action: Breakdown of hyaluronic

acid, the ground substance or intercellular

cement of tissues; minimizes tissue injury by

enhancing dispersion and reabsorption of extravasated fluids

Formulations available:

i. Animal derived: Ovine-derived Vitrase

(Alliance Medical Products, Irvine, California)

or bovine-derived Amphadase (Amphastar

Pharmaceuticals, Rancho Cucamonga,

California). Amphadase contains small quantities of thimerosal, so it is not recommended

in neonates.

ii. Recombinant human hyaluronidase

(rHuPH20) (Hylenex, Baxter Healthcare,

Deerfield, Illinois): This product is reported

to have up to 100 times greater enzymatic

activity than the animal-derived form, but

there is little literature available on its effectiveness in extravasations (15)

Most effective within 1 hour; may be used up to

12 hours

Administration: Use 25- or 26-gauge needles to

inject 1 mL (150 USP units/mL of Vitrase) as

five separate 0.2-mL injections around the

periphery of the extravasation site. If using

recombinant human hyaluronidase, a single

subcutaneous injection of 150 units using a

25-guage needle may be equally effective (15).

Most effective within 1 hour; may be used up to

12 hours after the extraversation.

Adverse effects: None reported in neonates, rare

sensitivity reactions to the animal formulations

of hyaluronidase reported in adults

d. Specific antidotes

Topical nitroglycerine (16,17)

i. Effective in treating injury due to extravasation

of dopamine

ii Mechanism of action: Vascular smooth muscle

relaxant

Application: 2% nitroglycerine ointment, 4 mm/

kg body weight, applied over the affected area,

A B