Post-operative Pulmonary Function After Kidney Surgery Under Two Different Techniques
Condition: Pulmonary Function
Study type: Interventional

Summary: 
      To assess the respiratory and analgesic effects of continuous thoracic paravertebral block
      versus thoracic epidural in patients undergoing kidney surgery
    

Detailed description: 
      Study tools

        -  An Ultrasound machine (Madison X6) with superficial linear and curved probe.

        -  A 19 gauge echogenic needle and Plexolong Cather (PAJUNK, Plexolong Meier nanoline,
           Geisingen, Germany; 60 mm).

        -  A 17-gauge Tuohy needle and 19 G flex-tip catheter: for thoracic epidural.

        -  Spirometer: (Enraf-Nonius, Model SPIRO 601).

        -  Drugs: isobaric bupivacaine 0.25% (aside from the drugs used in the standard operation
           theatre).

        -  Computer software: computer generated random tables (for randomization) and SPSS 22 (for
           data analysis)

      Thoracic epidural (TEP):

      A pre-procedural ultrasound examination will be done to first identify the correct targeted
      thoracic level. To accomplish this, the transducer will be placed in the parasagittal plane
      approximately 5 cm from midline. The thoracic level will be determined by identifying the
      12th rib and counting in a cephalad direction until the targeted level is marked.

      All epidurals will be performed under all aseptic precautions with a 17-gauge Tuohy needle
      and 19 G flex-tip catheters. Using the loss of resistance to saline technique, catheters will
      be inserted 4 cm into the epidural space and a suitable test dose will be administered to
      exclude intravascular or sub-arachnoid injection

      Bupivacaine 0.25% of 7.5-12 ml volume will be given through the epidural catheter then
      continuous infusion of bupivacaine 0.1% will be infused at a rate of 5 ml/h up to 15 ml/h
      with bolus infusion of 5 to 10 ml of the infusion mixture for breakthrough pain. The block
      height will be tested using pin prick method. After spirometry testing and diaphragmatic
      ultrasound, the infusion of TEP will be gradually weaned of and the catheter will be removed
      under complete aseptic precautions.

      Thoracic paravertebral block: (TPVB) The Ultrasound-probe will be centered on T7. The
      sagittal technique at the transverse process, in-plane, will be used. The 19 gauge echogenic
      needle will be inserted in-plane at the lower border of the transducer and advanced in a
      cephalad position with real-time ultrasound sonography.

      Injection of small amounts of fluid (hydro-dissection) will aid in needle tip location. When
      the needle tip reaches the paravertebral space, 7.5-12 ml Bupivacaine 0.25% will be slowly
      injected after negative aspiration. The endpoint for a successful block is anterior
      displacement of the pleura. The catheter will be then inserted through the needle and
      positioned up to 3 cm from skin entry directing upwards in the paravertebral space then
      continuous infusion of bupivacaine 0.1% will be infused at a rate of 5 ml/h up to 15 ml/h
      with bolus infusion of 5 to 10 ml of the infusion mixture for breakthrough pain.
    

Intervention name(s): thoracic epidural block; paravertebral block
Intervention type(s): Procedure; Procedure
Intervention description(s): thoracic epidural block with bupivacaine 0.25% will be given in the 8th thoracic space using ultrasound; paravertebral block with 0.25 bupivacaine will be given at the level of the incision using ultrasound
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Triple (Participant, Care Provider, Outcomes Assessor)
Primary purpose: Prevention
Keywords: kidney surgery; thoracic epidural block; paravertebral block