Reduction of Opioid Consumption after Major Spinal Surgery without Neurological Impairment by Block of Rami Dorsales

Abstract

Background: Epidural anesthesia reduces the demand on opioids after lumbar major spinal surgery. But it does not allow early postoperative assessment of motor function. Aims of the study were to elucidate a comparable effect of blocking rami dorsales on analgesic quality as well as an influence of this technique on motor function. Methods: Twenty two patients scheduled for lumbar interbody fusion were enrolled and divided randomly in 2 groups. Group A received a block of rami dorsales bilateral of fused vertebrae with bupivacaine 0.5% 2 ml 20 minutes before expected end of operation and a Patient Controlled Analgesia (PCA) pump. Group B received PCA pump only. The demand of piritramide to achieve a visual analogue pain score of less than 3 was given either by nurse or PCA pump when patients were cooperative. Setting of the PCA pump, co-analgesic and rescue medication was the same for all patients. Total sum of piritramide and rescue medication given within 24 hours postoperatively was recorded. Modified Bromage scale was assessed in all patients 1 hour after operation. Results: The groups were compared by pairs. The postoperative amount of piritramide given by nurse and by PCA pump differed significantly (P<0.05). The amount of piritramide given during stay in recovery room did not differ between the two groups. Modified Bromage scale was 0 in all patients. Conclusion: Block of rami dorsales reduces in a simple way the postoperative demand on piritramide in lumbar major spinal surgery without any impairment of lower extremity's motor function.