Study design: Comparative study of differing durations of antibiotics for spinal surgery.
Objective: To compare rate of infection, duration of hospital stay, days until normal body temperature, and a panel of blood tests after surgery between long-term and short-term administration of antibiotics for spinal surgery using instrumentation.
Summary of background data: Recent studies have reported that long-term administration of intravenous antibiotics is not necessary to avoid superficial and deep infections. We therefore changed the duration of administration from 9 to 2 days in our lumbar surgery patients.
Methods: We examined 135 patients (average age, 64.9 years) who underwent lumbar spinal surgery to insert a pedicle screw system to treat spinal canal stenosis. We administered 2 g of cefotiam daily to 60 patients for 9 days after surgery and to 75 patients for 2 days after surgery. Surgical time, loss of blood, rate of infection, duration of hospital stay, days until normal body temperature, and data from blood analysis (white blood cell count, and C-reactive protein [CRP] level) were statistically compared between the 2 groups.
Results: No significant differences in intraoperative measures of surgical invasion were observed between the 2 groups (surgical time, 209 vs. 220 minutes; blood loss, 530 vs. 576 mL; blood transfusion, 344 vs. 380 mL for the long-term and short-term groups, respectively). No acute infections occurred in either group. However, the duration of hospital stay (20.7 days), time until normal body temperature (5.1 days), and CRP level (2.23 mg/dL) at day 7 after surgery were significantly less in the short-term group than those in the long-term group (27.9 days, 6.8 days, and 3.13 mg/dL, respectively; P < 0.05).
Discussion: These results indicate that short-term intravenous administration of antibiotics did not elevate the infection rate after spinal surgery using instrumentation. However, long-term administration of antibiotics prolonged the duration of hospital stay, inhibited normalization of body temperature, and elevated CRP levels. Long-term administration of antibiotics may suppress normal, beneficial bacteria, thereby having an adverse effect on patient recovery.