[A comparison of two approaches to ultrasound-guided fascia iliaca compartment block for analgesia after total hip arthroplasty].

OBJECTIVE

To compare the efficacy of two approaches to ultrasound-guided fascia iliaca compartment block (FICB) for postoperative analgesia after total hip arthroplasty (THA).

METHODS

Approved by the Peking University Third Hospital ethics committee, Sixty patients undergoing selective total hip replacement in Peking Third Hospital during Oct. 2013 to May. 2014 were included. Before induction of general anethesia, ultrasound-guided FICB were administered. According to probe parallel to the inguinal ligament or perpendicular to the inguinal ligament, patients were randomly divided into the Parallel group and the Perpendicular group. Both groups was administered an equal volume mixture of 1% ropivacaine and 1% lidocaine, 30 ml in total. All patients received sufentanil postoperative intravenous analgesia after surgery. Time to ultrasonic imaging, time to perform the block and total blocking time were recorded. Loss of sensation in the distribution areas of the femoral nerve and lateral femoral cutaneous nerve within 30 mins were recorded. Patients were interviewed at 4, 8, 12, 24, 36, 48 h after block for pain intensity, time of first using PCA, sufentanil consumption and loss of skin sensation due to the block. The occurrence of adverse events (nausea, vomiting, respiratory inhibition, pruritus or urinary retention) was also recorded.

RESULTS

The imaging time of the Parallel group was shorter than the Perpendicular group [(3.1 ± 1.2) min vs (5.0 ± 1.7) min, t = -5.128, P < 0.05)], and performance time of the Parallel group was shorter than the Perpendicular group [(5.2 ± 1.3) min vs (7.1 ± 2.0) min, t = -4.376, P < 0.05)]. The successful rate for femoral nerve block was 100% both in 2 groups, while the successful rate for lateral femoral cutaneous nerve block in the Perpendicular group was 100%, and 83.3% in the Parallel group (χ² = 5.455, P < 0.05). The block rates for lateral femoral cutaneous nerve at 4, 8, 12 h after block in the Perpendicular group was higher than the Parallel group (P < 0.05). The consumption of sufentanil in the Parallel group was significantly higher than the Perpendicular group at 8, 12, 24, 36, 48 h after block (P < 0.05). There were no statistically differences in postoperative pain score, time of first using PCA, incidence of complications and patient's satisfaction score between the two groups.

CONCLUSION

Comparing the two approaches to ultrasound-guided FICB, ultrasonic probe perpendicular to the inguinal ligament may offer better blocking effect of lateral cutaneous nerve and reduce postoperative sufentanil consumption, and might be more suitable for analgesic after THA.