Postoperative Pain Relief After Cesarean Section: Is There a Role for the Quadratus Lumborum Block?
Condition: Postoperative Pain
MeSH terms: Pain, Postoperative
Study type: Interventional

Summary: 
      The Quadratus Lumborum block (QLB) was first described by Blanco in 2007. The main advantage
      of QLB compared to the Transversus Abdominis Plane block (TAP) is the extension of local
      anesthetic agent beyond the TAP plane to the thoracic paravertebral space. The wider spread
      of the local anesthetic agents produces extensive analgesia and prolonged action of the
      injected local anesthetic solution.

      Previous studies showed that TAP block may not be effective in improving postoperative
      analgesia in patients who had cesarean section under spinal anaesthesia.

      The aim of this randomised controlled, double blinded study is to examine the effect of QLB
      on the postoperative pain management in patients who had cesarean section under spinal
      anesthesia.
    

Detailed description: 
      After ethical committee approval, informed written consent will be obtained from all
      patients. A Sample size of 25 patients per group was calculated based on 15% reduction in
      morphine consumption with 0.05% significance and a power of 0.8.

      Consenting patients scheduled to have elective cesarean section under spinal anesthesia will
      be randomised to undergo QLB with Bupivacaine versus placebo(saline) after their surgery.
      Allocation will be done using closed envelope technique.

      The study medications/placebo will be prepared and labelled by an anesthetist who is not
      involved in the study.

      All patients will receive a standard spinal anesthetic. At the end of surgery , Quadratus
      lumborum block group (QL) patients will receive bilateral QLB with 0.125% bupivacaine.

      Control group patients will receive a bilateral placebo block using saline. The block will be
      performed in operation theatre after the end of cesarean section with intravenous access,
      ECG, BP, oxygen saturation by pulse oximetry monitoring and full resuscitation equipment and
      medication ready.

      The patient will be placed in a lateral position with the side to be blocked facing upwards.
      The ultrasound probe will be properly sterilized and with sterile covers.

      A 22 Gauge, two inch Pajunk Sonoplex needle is advanced under ultrasound guidance on the
      posterior aspect of the Quadratus Lumborum. Following negative aspiration, 0.2 ml/kg of
      0.125% bupivacaine, or placebo(saline) is injected in each side with intermittent aspiration
      and the spread of injectate followed on ultrasound.

      All patients will receive the routine postoperative analgesia, comprising patient-controlled
      IV morphine analgesia and regular diclofenac and paracetamol.

      All patients will be assessed postoperatively by a blinded investigator: in the
      postanesthesia care unit and at 2, 4, 6, 12, 24, 36, and 48 h postoperatively
    

Intervention name(s): Quadratus Lumborum block
Intervention type(s): Procedure
Intervention description(s): Patients will receive a bilateral Quadratus Lumborum block using 0.125% Bupivacaine in a dose of 0.2ml/kg body weight, after the end of surgery.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Treatment