Infection in penetrating abdominal trauma: risk factors and preventive antibiotics.

Infection remains the greatest risk for victims of penetrating abdominal injury with major infections occurring in 10 to 15 per cent. Attributable mortality is approximately 30 per cent of those who develop major abdominal infections. In addition to this morbidity infection adds approximately $43,000.00 of hospital charges per infected patients. This article addresses two significant areas: risk factors and antibiotic utilization. The most important risk factor is the presence of hollow viscus injury; colonic wounding carries the highest incidence of infection relative to intra-abdominal organs injured. Pancreatic and liver injuries significantly increase infection risk when combined with hollow viscus wounds. The degree of injury as measured by the volume of hemorrhage and the presence of shock as well as the anatomic degree of injury likewise correlates with the incidence of septic morbidity. Antibiotic utilization is addressed by the three issues of antibiotic agents of choice, duration of administration, and optimal dosing. Regimens of choice should include anaerobic coverage. Twenty-four hours of antibiotic administration is satisfactory with currently available agents. Evidence-based medicine analyses from the Eastern Association for the Surgery of Trauma have addressed those two issues. There are few data on optimal dosing. Increased volumes of distribution and rates of excretion have been demonstrated in trauma patients. This would suggest that higher-than-normal doses should be used. Laboratory studies would support such an approach. However, significant clinical research is desirable to address issues of concentration-dependent bacterial killing and time-dependent killing. Those pharmacodynamic considerations are variable among antibiotic classes.