Antibiotics and their complications in surgery

Abstract

s EPSIS still remains one of the major causes of postoperative morbidity and mortality. The lack of accurate records of the annual incidence of postoperative infections over a prolonged period of time precludes any assessment of recent changes in their frequency. There does not appear to have been any readily apparent change in the frequency of such infections, however, which is somewhat surprising since increasingly audacious surgical procedures are being carried out in older patients considered poor surgical risks. Almost everyone would agree that prevention is preferable to treatment of infections. This is certainly true of surgical infections in which irreparable structural damage may occur despite cure of the infection. The problem is that there are still serious gaps in our knowledge concerning the epidemiology and pathogenesis of wound infections. Two newly recognized sources of postoperative infections, intermittent positive pressure machines and venous catheters, deserve some emphasis, however, since these infections are often preventable. The increasing frequency of necrotizing gram-negative pneumonia, coupled with the knowledge that gram-negative bacilli thrive in water, prompted Reinarz et al. [1] to study bacterial contamination of inhalation therapy equipment. They found that 45 per cent of positive pressure respirators equipped with reservoir nebulizers delivered more than 2,500 gram-negative bacilli per minute in aerosols of the proper size to insure deposition in the alveoli of the lung. Contamination of ventilatory equipment leading to gram-negative pneumonia has become a significant problem in hospitals throughout the country. Intravenous catheters may also cause local infection and provide a source of gram-negative bacteremia and shock. In a prospective study in the Boston City Hospital, bacteremia originating from intravenous catheters occurred in 17 per cent of “cut-downs” [Z]. The mortality from gram-negative bacteremia in this hospital exceeds 50 per cent. These figures may not be representative of every hospital, but if they are, they suggest that the “cut-down” carries a fatality rate of 8 per cent which is comparable to that of major surgical procedures. More recent studies in the same hospital have shown a 1 per cent fatality rate directly attributable to the use of “intracaths” [3]. Both of these instruments have an important role in patient care, and therefore they cannot be discarded. However, they should be used with caution and should not become a routine in postoperative care. Preoperative exercises, judicious tracheal suctioning, and postoperative physical therapy will often completely obviate the need for postoperative ventilatory assistance. Similarly, the indication for venous catheterization is too often the fear of having to replace a needle in the middle of the night. The use of pediatric needles carefully taped in place can often substitute for venous catheters. When the use of ventilatory assistance is necessary, daily disinfection of the reservoir will decrease this hazard. Limiting venous catheterization to forty-eight hours per catheter, coupled with the use of local antibiotic ointment, will also reduce the risk. Indications for the use of antibiotics have not really changed since their introduction. What does present a problem is that physicians con-