Objective To investigate the effects of ultrasound-guided lumbar plexus and sacral plexus nerve block combined with general anesthesia on postoperative delirium(POD) in elderly patients treated with hip replacement surgery.

Methods Eighty elderly patients treated with unilateral hip replacement were randomly divided to the lumbar plexus and sacral plexus nerve block combined with general anesthesia group (group h) and general anesthesia group(group q)(40 cases in each group). The laryngeal mask airway(LMA), maintaining the bispectral index(BIS) for 40-60 and postoperative intravenous controlled analgesia(PCIA) were performed in two groups. The amount of anesthetic drugs and related indexes of operation were compared between two groups. The visual analogue scale(VAS) was used to evaluate the postoperative pain. The CAM scores in two groups before operation (D0), on the day 1(D1), day 3(D3) and day 7(D7) were measured. The serum levels of interleukin(IL-1β), IL-6, tumor necrosis factor α(TNF-α), C-reactive protein(CRP) and S100β protein were determined.

Results Compared with the group q, the intraoperative anesthetic dosage, postoperative extubation time, PCA frequency after 24 h of surgery, VAS score at each postoperative time point, first time out of bed and discharge time were significantly reduced in group h(P < 0.01). After operation, the levels of IL-1β, IL-6, TNF-α, CRP, S100β protein, CAM score and incidence rate of POD in group h were lower than those in group q (P < 0.01).

Conclusions The ultrasound-guided lumbar plexus and sacral plexus nerve block combined with general anesthesia can reduce the dosage of anesthetics, degree of pain, inflammatory response and incidence rate of POD, and promote the postoperative rapid recovery in elderly patients treated with hip replacement surgery.