Bulb Syringe and Pulsed Irrigation Which Is More Effective to Remove Bacteria in Spine Surgeries?

Study Design: Retrospective study. Objectives: The aim of this study was to investigate the difference of efficacy between bulb syringe irrigation and pulsed irrigation in spinal surgeries. Summary of Background: Pulsed irrigation has been used for more than half a century, especially in trauma surgeries. However, to the best of our knowledge, there has been no study as to the efficacy of pulsed irrigation in spinal surgeries so far. Materials and Methods: The consecutive patients who underwent posterior lumbar interbody fusion for 6 months were investigated. Those who underwent surgeries during the first 3 months were irrigated by bulb syringe (group I) and those who underwent surgeries during the next 3 months were irrigated by pulsatile irrigator with 17 psi (group II). Sex, age, surgery time, amount of blood loss, whether associated with diabetes mellitus, smoking, and amount of irrigation solution were compared between the 2 groups to identify homogeneity. Normal saline was used. Intraoperative irrigations were performed 3 times as time elapsed. After the last irrigation, culture specimens were obtained from the muscle layer and intervertebral space. The culture results were compared between the 2 groups. Results: There were 79 cases in group I and 59 cases in group II. In the homogeneity test, surgery time was longer (P = 0.011) and amount of irrigation saline was larger (P = 0.042) in group II. From the posterior muscle layer, bacteria were cultured in 8/79 cases (10.1%) in group I and 1/59 cases (1.6%) in group II. There was a significant difference between the 2 groups (P = 0.046). And from the intervertebral space, it was cultured in 6/79 cases (7.6%) in group I and 5/59 cases (8.5%) in group II. There was no difference between the 2 groups (P = 0.546). Staphylococcus epidermidis, Staphylococcus aureus, Staphylococcus hominis, and Staphylococcus saprophyticus were cultured in order of the frequency. Conclusions: Pulsed irrigation was more effective compared with bulb syringe irrigation in the posterior muscle layer. In the intervertebral space, however, both methods were insufficient to eradicate contaminated bacteria.