Topical use of streptomycin in wounds

Abstract

1. 1. For topical application to wounds, a solution of streptomycin of the proper concentration should be used, not the powder. Freshly wounded tissues are not damaged further and wounds heal without interference when the concentration of streptomycin is at 200 units or micrograms per cc. Granulations are not damaged by 1,000 units per cc. At these concentrations, streptomycin is the best non-toxic antibiotic that has been found to date for gram-negative bacilli. 2. 2. Penicillin, up to 1,000 units, or sulfamylon 5 per cent should always be combined with streptomycin when it is used topically because streptomycin does not have a complete bacterial spectrum at its proper concentration and some susceptible bacteria rapidly acquire resistance to streptomycin alone. 3. 3. Conversely, streptomycin should always be used topically with penicillin because streptomycin kills gram-negative bacilli that penicillin is unable to destroy and these elaborate penicillinase that in turn destroys penicillin. 4. 4. Gram-negative bacilli are almost always present at some time in the evolution of the bacterial flora of wounds even though only a single strain of bacteria may be isolated at one time. Gram-negative bacilli usually dominate the flora of chronically infected wounds, accounting in part for the failure of topical application of penicillin alone in this type of wound. 5. 5. Gram-negative bacilli definitely interfere with the healing of wounds despite arguments that have been advanced that they are mere contaminants of pus. 6. 6. Because of its stability, sulfamylon 5 per cent makes a better combination with streptomycin than with penicillin. Sulfamylon has a wider bacterial spectrum than penicillin though it is not always as powerful and it acts rapidly in the presence of pus. It can be used with any form of parenteral therapy. This mixture encounters few resistant strains of bacteria. 7. 7. Topically, the solution of streptomycin and penicillin or sulfamylon will prevent infection in wounds better than it will hasten the resolution of established infection, except in certain instances in which no slough is present. 8. 8. In the presence of crushed tissue, prevention of infection can be obtained experimentally until three hours after wounding by washing the wound and injecting about 20 cc. of the solution in the surrounding tissues. With débridement of crushed tissue, prevention of infection has been effected as late as forty-eight hours after wounding when the solution is employed in the same manner. 9. 9. All devitalized tissue cannot be débrided from traumatic wounds nor can the process always be done in time; therefore, topical application of the solution of streptomycin and penicillin or sulfamylon is recommended in the treatment of traumatic wounds as a safety factor to prevent infection. 10. 10. The solution of streptomycin and penicillin or sulfamylon will decontaminate the clean-contaminated operative wound. The solution is applied topically before the wound is closed as one would an antiseptic to the skin. 11. 11. To hasten resolution of the established localized infection in the wound, adjunct chemotherapy in addition to antibacterial chemotherapy is required. This adjunct chemotherapy must liquefy slough and cause the antibacterial substances to penetrate and kill bacteria in slough and leukocytes. 12. 12. A mixture of acid, glycerine and thymol has been used for this adjunct chemotherapy. It is successful when sloughing fascia is present but it is not successful in the presence of osteomyelitis. 13. 13. Streptomycin alone can rid wounds of persistent gram-negative bacilli infection when no slough is present in the wound. For example, granulations that will not take skin grafts because they harbor a flora of the gram-negative bacilli can be freed of these bacteria by the local application of streptomycin and then skin grafts will take. 14. 14. No otic complications have been observed with the low concentration of streptomycin used topically. However, topical therapy has not been used as frequently nor over such long periods of time as parenteral therapy.