Popliteal block for lower limb surgery in children with cerebral palsy: effect on sevoflurane consumption and postoperative pain (a randomized, double-blinded, controlled trial).

PURPOSE: The aim of this study was to evaluate the effects of a preoperative popliteal block on sevoflurane consumption, postoperative pain, and analgesic consumption in children with cerebral palsy (CP) following lower limb surgery.

METHODS: Fifty-four patients undergoing lower limb surgery were randomized to receive either a popliteal block + general anaesthesia (group P, n = 27) or general anaesthesia without a popliteal block (group C, n = 27). After anesthesia induction with 50% N2 O, O2 , and 8% sevoflurane, a popliteal block was given to group P patients with ultrasound guidance as a single dose of 0.3 ml/kg body weight of 0.25% bupivacaine. Group C patients received the same regimen of anesthesia induction but no preoperative popliteal block. Both the conductance fluctuation (SCF) peak numbers per second and the Wong-Baker FACES® Pain Rating Scale (WBFS) values of the patients were recorded upon arrival at the PACU, at 10 and 20 min after arrival at the PACU, and at postoperative hours 1, 4, 8, 12, and 24 when they were in the ward. The total paracetamol consumption of the patients was also recorded.

RESULTS: The end-tidal sevoflurane concentration values were significantly higher in group C patients than in group P patients, except for at 5 min after induction of anaesthesia (p < 0.001). The SCF peak numbers per second and WBFS scores were significantly higher in group C patients than in group P patients, except at Tp24h (p < 0.001). The total paracetamol consumption was 489.7 ± 122.7 mg in group P patients and 816.6 ± 166.5 in group C patients (p < 0.001).

CONCLUSION: Popliteal block is effective for postoperative analgesia, decreasing the paracetamol consumption and sevoflurane requirement in children with CP undergoing lower limb surgery. Trial registration ClinicalTrial.gov identifier: NCT02507700.