Effects Of Ultrasound-guided Quadratus Lumborum Block On Postoperative Analgesia After Caesarean Section

Objective To investigate the effect of ultrasound-guided quadratus lumborum block on postoperative analgesia after caesarean section.Methods Sixty parturients,20-40 years,150-170 cm,50-80 kg,ASAâ… orâ…¡grade,scheduled for cesarean section,were randomly divided into 2 groups（n=30 each）using a random number table:QLB group（group Q）and control group（group C）.Parturients in group Q received bilateral quadratus lumborum block with the use of 20 mL 0.33%ropivacaine per side after surgery,while quadratus lumborum block was not done in group C.Both groups received patient-controlled intravenous analgesia（PCIA）after surgery which contains 800 mg tramadol,40 mg nefopam and 60 ml saline.The accumulative consumption of tramadol,the score of numerical rating scale（NRS）for pain at rest and on movement and the bruggrmann comfort scale（BCS）score were recorded at 4,8,12,24,48 h after operation.The cutaneous sensory block area was determined in group Q at4,8,12,24,48 h after operation.The patient’s satisfaction with postoperative analgesia and adverse reactions were also recorded.Results The consumption of tramadol in group Q was significantly decreased compared with that in group C（P<0.05）at 4,8,12,24,48 h after surgery.NRS for pain at rest at all times,NRS for pain when cough at12,24 h after surgery and NRS for pain when turning over at 4,48 h after surgery were significantly lower,while the BCS score was higher in group Q than that in group C（P<0.05）.Quadratus lumborum block affected T₇-L₁dermatomes at 4,8,12 h after surgery and T₈-L₁ dermatomes at 24 h after surgery.The analgesic plane of quadratus lumborum block disappeared at48 hours after operation.The patient’s satisfaction with postoperative analgesia was higher in group Q compared with that in group C（P<0.05）.The incidence of postoperative nausea,vomiting and dizziness was similar between the two groups.Conclusion Ultrasound-guided quadratus lumborum block can remarkably reduce the consumption of tramadol after caesarean section,lower the postoperative pain score,improve the patient’s comfort and satisfaction.This technique is worth to be applied in clinical practice.