The efficacy of pre‐ versus postsurgical axillary block on postoperative pain in paediatric patients

Abstract
We compared the effects of pre‐ and postsurgical axillary block on pain after hand and forearm surgery in 55 children in a double‐blind randomized study. The successful blocks are reported here (n=49). Children aged 1–11 years and ASA I or II were allocated randomly to receive axillary block with 2 mg.kg−1 of 0.25% bupivacaine, either after induction but before the surgery (presurgical group, n=25) or immediately after surgery, before the end of anaesthesia (postsurgical, n=24). In all patients, a standard general anaesthesia technique was used. The Faces Pain Scale (FPS) and analgesic requirements were recorded for 24 h at various times after operation. Eight patients (32%) in the presurgical group and 20 patients (83.33%) in the postsurgical group did not require additional analgesic within the first 24 h after operation (P< 0.05). In patients who had pain during the observation period, the pain started 13.66±2.61 h in the presurgical group and 13.14±2.34 h in the postsurgical group after performing block (P> 0.05). The FPS scores were similar in both groups during the first 8 h in the postoperative period (P> 0.05). There was a significant difference at 10 h after surgery (P< 0.05). Cumulative FPS score was higher in the presurgical group (10.50±1.06) than in the postsurgical group (9.45±1.28) (P< 0.05), but both groups had effective analgesia overall, the mean FPS score being less than 2. Additional analgesic consumption was similar in these patients in both groups. A lower isoflurane concentration was used in the presurgical group (0.68%vs 1.72%, P< 0.001). We did not demonstrate the superiority of preemptive analgesia, but our results indicate that presurgical axillary block with 0.25% bupivacaine allows the use of inhalational anaesthetics at lower concentrations while providing a reasonably painless postoperative period.