SUPERIORITY OF AZTREONAM CLINDAMYCIN COMPARED WITH GENTAMICIN CLINDAMYCIN IN PATIENTS WITH PENETRATING ABDOMINAL-TRAUMA

There were 73 evaluable patients entered into a prospective, double-bl inded trial comparing aztreonam/clindamycin (A/C) to gentamicin/clinda mycin (G/C) for the prevention of infection after penetrating abdomina l trauma. Aztreonam was administered at a dosage of 2 g every 8 hours and gentamicin at 5 mg/kg for the first 24 hours and then adjusted by serum monitoring to a peak of 6 to 8 mug/mL and a trough of less than 2 mug/mL; all patients received 900 mg of clindamycin every 8 hours. P atients with colon wounds received 4 days of antibiotics, and the rema ining patients received a 24-hour course. Gunshot wounds occurred in 6 9% of patients: 74% of all patients had some hollow viscus injury, and 26% had only solid viscus injury. The groups were well matched accord ing to abdominal trauma index, percentage with colon injury, and trans fusion requirements. Failures occurred in eight patients (11%): two wo und infections, five intra-abdominal infections, and one case of necro tizing fasciitis. Seven infections occurred in 36 (19%) G/C patients c ompared with 1 in 37 (3%) A/C patients (p < 0.03). The hospital stay w as 12 +/- 11 days for G/C patients and 8 +/- 7 for A/C patients (p < 0 .12). The superiority of the A/C regimen may be partially attributable to relative underdosing of gentamicin (approximately half of the pati ents had inadequate levels after 24 hours) combined with a favorable p harmacokinetic profile (significantly prolonged half-life) of aztreona m in this clinical setting.