TABLE 4.

Recommendations for preventing and managing vascular complications associated with filler injections

PREVENTIVE STRATEGIES
Practitioner
	Deep knowledge of the vascular anatomy is key for preventing vascular complications. In addition to good anatomical background knowledge, practitioners should consider the following aspects: •Possible altered anatomical connections in patients with previous surgeries •Possible anatomical variants during the development of some blood vessels; precaution should be taken in all face areas, including the upper lip and the wing of the nose •Possible extended vascular anastomoses of the nasal region from the perioral to the periorbital region, which might spread the filler from one area to the other.
Filler choice
	Use reabsorbable products appropriate for the type of correction and therefore for the implant level. Hyaluronic acid fillers are typically noninflammatory products and have a purely mechanical effect, unlike collagen and autologous fat, which seem to activate the “clotting mechanism.”
Injection technique
	•Use a delicate retrograde injection technique. •Use very slow injection rates. •Apply light pressure on the syringe plunger (consider the use of an electronic device). •Distribute the product in various points by injecting small amounts of it (i.e. <0.1 mL). •Use a microcannula for deep injections and very viscous products (strongly recommended). •Use fine needles only for superficial injections. •Always aspirate before injection.
MANAGEMENT OF COMPLICATIONS
Immediate pain and/or bleaching of the area (typically a few seconds after injection)
	Immediately stop injecting; vigorously massage the area.
Possible livedoreticularis or reactive hyperemia (it may occur up to 10 minutes after injection)
	Treat immediately to restore the vascular flow.
Possible arterial insufficiency (slow capillary reloading with acupressure)
	Apply warm gauzes, topical paste or patch of nitro-derivatives; inject hyaluronidase (independently from the type of filler injected) and apply a local massage.
Dark-blue discoloration of the area (it may occur from ten minutes to hours)
	Contact your plastic surgeon and consider using systemic antibiotics, steroids, aspirin, low molecular weight heparin, prostaglandin.
Blisters and boils after a few days
	Gently disinfect by swabbing the area; pierce the boils and gently favor the spillage of the serum; leave a gras gauze dressing with antibiotic on the skin for no more than three days, then remove it (with clamp and scissors), gently disinfect with 3% boric acid and medicate with a gras gauze dressing and antibiotic ointment until complete repitelization of the area.
Necrosis (can appear after days or weeks)
	Apply antibiotic ointments until eschar demarcation; after removal of the necrotic tissue, apply products intended to improve tissue regeneration such as hydrocolloids gel, plates or collagen tablets on the loss of residual substance.
Ocular complications
Contact an eye surgeon immediately. In the meantime, try to reduce eye pressure through ocular massage, timolol drops, acetazolamide/manitol, steroids, haemodilution, oxygen therapy, antiplatelet/anticoagulant, thrombolysis, decompression of the eye anterior chamber.