Antibiotics in surgery

Antibiotics have two uses in surgery: (1) To treat established infections. (2) In certain circumstances only, and when used in a very particular way, to prevent postoperative infection. They have deliberately been placed last in this chapter, because they are less important than: (1) Careful aseptic theatre routines. (2) A thorough wound toilet (54.1). (3) Delayed primary closure (54.4). (4) Making sure there are no foreign bodies, dead tissue, excessive blood clots, or faeces in the wound. In preventing sepsis, antibiotics give you no licence to neglect the classical rules of good surgery, especially if the patient is diabetic, very old, or very ill, and so less able to overcome any bacteria that may get inside him. So: (1) Handle the tissues gently. (2) Don't leave large pieces of dead tissue in the wound, such as huge, massively ligated pedicles. (3) Where necessary, divert faeces by temporary colostomy.

That said, how can you use antibiotics to the best advantage, when your laboratory staff cannot culture bacteria, or at least not reliably? If they can, do encourage them to examine blood cultures, which are not difficult technically, and, when these are positive, to isolate the organism responsible for septicaemia in pure culture.

If you are fortunate, you will be able to plan a logical antibiotic policy for your district, and keep some antibiotics for hospital use only, in the hope that the arrival of antibiotic-resistant strains from elsewhere in the world will be delayed as long as possible. In such an ideal situation you might decide, for example, that the clinics should use only penicillin and tetracycline, with perhaps a little ampicillin or trimethoprim, and keep streptomycin for tuberculosis only. This will enable you to use chloramphenicol with metronidazole as your main surgical antibiotics, especially when the gut and the genital tract are involved. For other occasions you can use gentamicin (expensive), or a cephalosporin, or a combination of penicillin and streptomycin.

Unfortunately, you are more likely to work in a situation of antibiotic chaos, in which any antibiotic is obtainable over the counter without prescription, and where multiply resistant strains, particularly those resistant to chloramphenicol, are common.

The advice given in later chapters assumes that you are working in an area where chloramphenicol is not freely available in the community, and where organisms resistant to it are uncommon. If they are common, the advice we give may no longer hold, and you had probably better use gentamicin or cephradine.

Fig. 2-9 ANTIBIOTICS MUST GET TO THE PATIENTS AND THE DISEASES WHERE THEY CAN DO MOST GOOD. This is a poster from Oxfam's ''Rational Health Campaign' to show the enormous burden many communities bear in misused antibiotics that are bought in the marketplace, or are misprescribed by doctors on the wrong indications for the wrong patients. Some of the most valuable correct uses of antibiotics are the surgical ones described here. Kindly contributed by Oxfam.