Australasian Dentist Issue 92

CATEGORY 78 AUSTRALASIAN DENTIST Dr Giulia D’Anna Using a cannula for dermal filler By Dr Giulia D’Anna, BDSc, MRACDS, Grad. Dip. Derm. Th Cert IV TAE, Grad. Cert laser LINICAL N o matter how experienced you are in the use of cosmetic injections, every practitioner should be aiming to prevent, avoid and manage complications when treating patients. This is particularly the case when using dermal filler.It is difficult to know exactly how many adverse events occur in Australia every year as a result of dermal filler, but we do know that many can take place. The most common complications following dermal filler are swelling and bruising. Whilst these are ‘annoying’, they are certainly not debilitating long term. A much more serious complication is vascular compromise, which can quickly become a medical emergency. So let’s look at what a vascular compromise actually is, how to avoid it and how to treat it. Vascular compromise or occlusion Vascular compromise is also known as an arterial or vascular occlusion. This is where there is a changed blood supply to an area of the face as a result of a blockage or reduced blood flow to the skin and tissues. Vascular compromise is usually seen very early on post- treatment, occurring within 24 hours of hyaluronic acid injection. Vascular compromise is caused by injection of the filler onto an artery of the face, preventing arterial or oxygenated blood from flowing onto the tissue it supplies. The patient will usually experience pain which is severe in nature, and the tissues that are becoming hypoxic turn white or blue in colour. Vascular compromise can occur via two main mechanisms. 1. Dermal filler can be injected directly into the blood vessels, blocking the flow of oxygenated blood. As an artery passes through to the terminal vessels, the vessel goes from being large diameter to a much smaller size at its end. This forms a filler ‘plug’ that overwhelms the blood pressure, stopping it from flowing. 2. Compression of the vessel, where a large volume of filler is placed over the vessel, reducing the flow of blood significantly to the tissues. Stages of Vascular Occlusion (VO) Briefly, there are 5 stages of vascular occlusion. Every cosmetic injector should be aware of these, as this is a time critical event. The stages of vascular occlusion are: Stage 1: Pain Severe pain is usually experienced by the patient at the time of injection. However, if local anaesthetic has been used (either topically, a nerve block, or administered with the product) this symptom can be less reliable. Extraordinary pain is not a feature of soft tissue filler treatments, and if a patient complains of sudden or escalating pain during treatment or in the hours following treatment, this should alert the practitioner to the possibility that a vascular occlusion has occurred and warrants an urgent review. Injectors should be aware that pain distant from the injection area can also be a warning sign of vascular occlusion. Blanching When the vasculature is affected, the area will often initially look pale, white, or dusky, due to the reduction in blood supply to the affected tissue. This colour will remain after removal of the needle or cannula. The blanching might initially be transient and local, but if unresolved, the pattern of the blanching will become reticulated or irregular, following the same path as the blood supply that has been restricted. This blanching might be masked initially, if adrenaline or certain topical anaesthetics have been used. Stage 2: Dusky, purple discoloration This is more typical several hours following treatment and is due to the accumulation of deoxygenated blood in the affected tissues. The appearance canmimic that of bruising, but bruises do not blanch, as they are caused by blood leaking into the skin. Stage 3: Skin Breakdown Opportunistic infection with anaerobic infection predominates due to lack of oxygen in the tissues. Antibiotics that target anaerobes needs to be considered as a treatment after Hyalase has been performed. This is the final stage that a cosmetic injector can rectify the blood supply and the patient shouldmake a full recovery without surgical intervention.