Efficacy of continuous lumbar plexus block combined with a bolus dose added at night for postoperative analgesia in patients undergoing hip arthroplasty / 中华麻醉学杂志

ABSTRACT

Objective To evaluate the efficacy of continuous lumbar plexus block (CLPB) combined with a bolus dose added at night for postoperative analgesia in patients undergoing hip arthroplasty.Methods Sixty ASA Ⅰ or Ⅱ patients of both sexes,aged 51-75 yr,weighing 47-77 kg,with body height 150-180 cm,scheduled for hip arthroplasty,were randomized to receive either CLPB (group CLPB) or patient-controlled intravenous analgesia (PCIA) (PCIA group) for postoperative analgesia (n =30 each).Spinal anesthesia was performed at L3,4 interspace.Postoperative analgesia was performed at 30 min before the end of surgery.PCIA solution contained morphine 100 mg in 100 ml of normal saline.The PCA pump was set up with a 2 mg bolus dose and a 5 min lockout interval.CLPB solution contained 0.125 ％ ropivacaine hydrochloride 200 ml.CLPB pump was set up to deliver a 4 ml bolus dose with a 30-min lockout interval and background infusion at 8 ml/h after a loading dose of 0.125％ ropivacaine 30 ml.In addition the patients received 0.25％ ropivacaine 30 ml at 8 o' clock every night after surgery in group CLPB.VAS scores at rest and during activity were recorded at 6,12,18,24,30,36,42 and 48h after operation.The side effect such as nausea and vomiting,pruritus and urinary retention were recorded within 48 h after operation.The patient' s satisfaction was assessed.The maximal hip flexion and abduction ranges of motion were recorded at 12,24,36 and 48 h after operation.The times of sleep interruption resulted from pain during nighttime were also recorded.Results Compared with group PCIA,the VAS scores during activity,severity of nausea and vomiting,pruritus and urinary retention,and times of sleep interruption resulted from pain during nighttime were significantly decreased,and the overall satisfaction score and maximal hip flexion and abduction ranges of motion were increased in group CLPB (P ＜ 0.05).Conclusion CLPB combined with a bolus dose added at night can provide better efficacy for postoperative analgesia in patients undergoing hip arthroplasty than PCIA,with fewer complications.