EFFECTS OF ANTIBIOTIC OINTMENTS AND ANTISEPTICS ON SKIN FLORA BENEATH SUBCLAVIAN CATHETER DRESSINGS DURING INTRAVENOUS HYPERALIMENTATION

There is no established principle for choosing topical antimicrobial agents during TPN [total parenteral nutrition]. The present study examined the relation between the topical antibiotic ointment applied and the skin flora isolated from the skin beneath the subclavian dressing. Neosporin, a broad-spectrum antibiotic ointment without fungicidal properties, did not predispose to overgrowth of Candida. Hence, use of this ointment is not related to TPN fungemia. Betadine, a fungicidal ointment with limited abilities to kill gram-positive organisms, did not permit overgrowth of commensurate skin bacteria. A specially compounded mixture of neosporin-mycostatin, designed to compensate for the deficiencies of neosporin and betadine, respectively, failed to completely suppress the growth of skin flora. The majority of positive cultures were isolated from patients whose skin was cleansed with saline rather than 10% PVP [polyvinyl pyrrolidone], suggesting that antiseptic skin preparation is more important than the antibiotic ointment applied thereafter. No treatment completely eradicated skin organisms. This raises the possibility that daily subclavian dressing changes might reduce the incidence of TPN-related septicemia. Such a proposal must be weighed against the time and expense factors involved.