The filler crash cart that Ontario, Canada, plastic surgeon Claudio De Lorenzi, M.D., recommended years ago has narrowed significantly. Now, he says, physicians need only bovine testicular hyaluronidase (HYAL) and knowledge.
And the knowledge needed is less than in the past because providers don’t have to remember all the other stuff.
“[Knowledge about] hyperbaric oxygen, prostaglandins, eye of newt, toe of frog, wool of bat and tongue of dog. All unnecessary!” Dr. De Lorenzi jokes.
But seriously, physician injectors need to know how to stay out of trouble, as well as what to do when trouble happens, according to Dr. De Lorenzi, who presented “Injectables, anatomy and safety,” Tuesday at the Aesthetic Meeting of the American Society for Aesthetic Plastic Surgery (ASAPS) in Las Vegas.
“Avoidance is primary strategy, but if you get into trouble: HYAL and lots of it (about 450 IU per cubic inch of ischemic tissue). Rinse and repeat hourly until resolution,” Dr. De Lorenzi says. “Everything else is superfluous. We want HYAL flooding of the ischemic tissue."
According to Dr. De Lorenzi, dosing is 3 cc of 150iu/cc HYAL per cubic inch of ischemic tissue. The goal is to ensure that all the obstructed vessels are surrounded with a sufficient concentration of HYAL for a sufficient length of time to hydrolyze HA fillers inside the arteries. Flood the ischemic tissue and gently massage the area, he says.
“We want flooding because the HYAL has to pass through the vessel wall with enough local concentration to hydrolyze the HA filler inside the vessel — especially if the entire vessel is full, or if the initial HA bolus has broken up into smaller blobs that have subsequently passed into smaller vessels downstream,” he says.
And the bigger the area, the more HYAL. That’s because HYAL dosing is based on how much tissue one treats, according to Dr. De Lorenzi.
“Repeat treatment hourly until you have restored cutaneous perfusion,” he says. “It is the HYAL that dissolves the emboli…it is always intravascular embolus/emboli. It's never external compression….”
A couple of tips for staying out of trouble:
When doing filler treatments, cosmetic and plastic surgeons should use a small bolus technique (i.e. less than 0.1 mL per pass), according to Dr. De Lorenzi.
“High-volume intravascular events are far more difficult to treat and, more often, involve other systems (which can result in blindness, hearing loss, stroke, etc),” he says.
Finally, physician injectors should ensure they start with an adequate supply of HYAL. Having about 4500 IU immediately available is a reasonable start, according to Dr. De Lorenzi.
“How are you going to get more HYAL in an emergency?” he says. “Not a bad idea to think about that before it happens, especially in smaller, geographically isolated communities.”
Disclosure: Dr. Lorenzi is medical director for Allergan, Canada, and Merz, Canada. He is on the advisory board for Kythera Biopharmaceuticals, Suneva Medical and Valeant Pharmaceuticals.