Incompatibility of Betadine Mixed with Marcaine as an Irrigant for Breast Implant Pockets

Abstract

Sir:FigureFor years, we have rinsed the breast implant pocket out with a mixture of bupivacaine and povidone-iodine (Betadine) before inserting the implant.1–8 We also first inject some bupivacaine into the incisions and the edges of the released pectoralis muscle. For years, we have been provided with Sensorcaine, which is the brand name of the product manufactured by AstraZeneca. When our hospital started bringing in bupivacaine under the brand name Marcaine, provided by Hospira, the mixture with Betadine (10 cc of Marcaine and 5 cc of Betadine) would turn clear before it was used for irrigation. This did not happen with Sensorcaine. We called the three companies that provided Betadine, Sensorcaine, and Marcaine, and although they all responded quickly, they had no idea what was happening. It appears that Sensorcaine uses sodium hydroxide and hydrochloric acid to balance the pH. Marcaine did not list hydrochloric acid on its label but it did list ascorbic acid. On the Web site, the company states that ascorbic acid is used as an antioxidant. It is interesting to watch Betadine turn clear when ascorbic acid (vitamin C) is added (Fig. 1).Fig. 1: (Above) Betadine in container. (Center) Approximately 5 seconds after addition of vitamin C crystals with some clearing of color around the crystals. (Below) It took 15 seconds for the color of the Betadine to completely disappear.The second photograph shows some clearing of the Betadine where the ascorbic acid crystals were added. The final photograph shows complete clearing with resolution in addition to most of the “iodine” smell. It turns out that many back-country campers decontaminate their drinking water by using either tincture of iodine (the elemental iodine is not soluble in water and is therefore dissolved in ethanol) or Lugol solution, where potassium is used to make the iodine soluble in water through the formation of triiodide (I3–) ion. After the iodine solution has been in the water for 20 minutes, they then neutralize the iodine with ascorbic acid. The chemical reaction converts ascorbic acid to dehydroascorbic acid and reduces the iodine: C6H8O6 + I3− + H2O → C6H6O6 + 3I− + 2H+ Betadine complexes elemental iodine with povidone or polyvinylpyrrolidone to maintain its antiseptic properties without the toxicity and irritation that was common with tincture of iodine. The antiseptic action of Betadine is therefore neutralized when it is mixed with Marcaine but is still effective when used with Sensorcaine. We assume that there may be other surgeons who use bupivacaine as an injection for pain control. Whether or not they add bupivacaine to the irrigant, we suspect that some of the Betadine will be neutralized by the ascorbic acid in the injection when Marcaine is used as a brand. We are also aware that some surgeons will soak the implant in Betadine and then, after the incision is closed, they will insert bupivacaine into the pocket through the drain, clamp it for a while, and then release it. If they have used bupivacaine with ascorbic acid, they will be unaware that the antiseptic effect of the Betadine will have been neutralized. It appears that only the Marcaine brand uses ascorbic acid. Naropin (ropivacaine), made by AstraZeneca, uses sodium hydroxide and hydrochloric acid. They do not list ascorbic acid in their ingredients. The same information was found for Chirocaine (levobupivacaine), made by Abbott Laboratories. Elizabeth J. Hall-Findlay, F.R.C.S.C. Ben Strong, M.R.C.S.(Ed.) Patricia Edgar, B.Sc., M.D. Banff Plastic Surgery, Banff, Alberta, Canada DISCLOSURE The authors have no financial interest in any of the products, devices, or drugs mentioned in this article.