PREEMPTIVE EFFECT OF PRE-INCISIONAL VERSUS POST-INCISIONAL INFILTRATION OF LOCAL-ANESTHESIA ON CHILDREN UNDERGOING HERNIOPLASTY

Background: Although promising in experimental studies of post-traumat ic pain, the concept of pre-emptive analgesia is still controversial i n a clinical setting. Thus, we wanted to compare the clinical efficacy of wound infiltration with local anaesthesia before surgery with woun d infiltration after hernioplasty in children. Methods: Fifty children aged 2-10 years scheduled for hernioplasty were randomly assigned int o two groups. Group 1 (n=28) was infiltrated before surgery with bupiv acaine 2.5 mg/ml, 1 mg/kg after induction of general anaesthesia. Afte r surgery they were infiltrated with the same volume of 0.9% saline. G roup 2 (n=22) was infiltrated with 0.9% saline before surgery and bupi vacaine 2.5 mg/ml, 1 mg/kg after surgery. The study was performed doub le-blindly. In both groups anaesthesia was induced with thiopenthone a nd maintained with nitrous oxide and halothane, adjusted to keep haemo dynamic measurements stable. All children were given paracetamol 15-20 mg/kg rectally when admitted to the recovery ward. Painscore (OPS) an d analgesic requirements were registered postoperatively. After 48 h t he parents completed a standardised questionnaire and they were interv iewed by telephone after one week. Results: The pre-incisional group n eeded significantly less halothane during the procedure compared with the post-incisional group (P<0.05). The pre-incisional group also had a tendency towards faster awakening after the end of anaesthesia and a significantly lower OPS-pain score 30 min after the operation (P<0.03 ). There were no differences between the two groups regarding need for additional analgesia: meperidine i.v. during the first 5 h postoperat ively, and paracetamol thereafter. There were no differences between t he groups regarding activity level, appetite and quality of sleep in t he first ear week. In both groups the need for opioid analgesics was l ow: 54% in the pre-incisional group and 45% in the post-incisional gro up did not receive any opioid analgesic treatment. The children were v irtually fully recovered after the first 24 h. Conclusion: Perioperati ve infiltration with a local anaesthetic in children undergoing hernio plasty results in a smooth recovery with Little need for opioids posto peratively. Apart from a lower anaesthetic requirement and a reduced p ostoperative pain level after 30 min in the pre-incisional bupivacaine group, there was no difference between infiltration before (pre-empti ve) or after surgery.