Epidural Block vs. Rectus Sheath Block on Postoperative Pulmonary Function
Condition: Abdominal Surgeries
Study type: Interventional

Summary: 
      Pulmonary complications are among the most important postoperative complications after
      midline incisions, for which different analgesic modalities have been tried.

      Epidural analgesia is the recommended technique to relieve pain after major abdominal surgery
      owing to the proved superior analgesia, reduction of opioid related side effects as nausea,
      vomiting, pruritis and sedation, earlier recovery of bowel function and earlier ability for
      postoperative mobility However, it is not without complications.

      Rectus sheath block provides several advantages over epidural anesthesia. It lessens the
      potential risks associated with neuraxial techniques, so it may represent a novel alternative
      approach for somatic analgesia after major abdominal surgeries. Although patients with rectus
      sheath block may experience some visceral pain, it is usually minimal by 24 hours after
      surgery.
    

Detailed description: 
      The aim of this study is to compare the effects of thoracic epidural analgesia and rectus
      sheath blockade on postoperative pulmonary functions, pain scores, duration of analgesia,
      sedation scores, patients' satisfaction and adverse effects.

      FEV1, FEV1/FVC ratio will be measured by a bed side spirometer.

        -  Induction of anesthesia: propofol 1.5-2.5 mg kg-1.

        -  Muscle Relaxants: rocuronium 0.6 mg kg-1 for induction.

        -  Maintenance: Sevoflurane 0.7-1.5 MAC vaporized in air-oxygen (40% inspired fraction).

      Radial artery catheterization: under complete aseptic conditions 20G cannula will be inserted
      into the radial artery of non-dominant hand after performing modified Allen's test and local
      infiltration of 0.5ml xylocaine 2% .

      Thoracic epidural catheter will be inserted before induction of general anaesthesia under
      aseptic insertion conditions and using loss of resistance to air technique with the patient
      in the sitting position at T9- T11 interspaces.

      The Rectus sheath catheters will be inserted bilaterally using ultrasound (SonoSite M-Turbo®,
      Sonosite , USA) guidance as described by Webster after induction of general anaesthesia.
    

Intervention name(s): Thoracic epidural analgesia (TEA); Rectus sheath catheter block
Intervention type(s): Other; Other
Intervention description(s): Epidural catheter will be inserted at T9-T11. Then, epidural analgesia will be activated with administering bolus of 10 mls 0.25% bupivacaine in conjunction with100 mcg fentanyl to establish a block. This will be followed by an infusion of 0.125% bupivacaine in conjunction with 2 mcg/ ml fentanyl at a rate of 10 mls /hour and then titrated to effect for up to 48 hour postoperative; Following insertion of bilateral rectus sheath catheters, 20 ml of 0.25% bupivacaine will be injected through each one. Then continuous infusion pumps will be connected to the catheters and set to deliver boluses of 20 mL of 0.25% bupivacaine, with a 4-hour lockout for up to 48 h postoperatively.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Triple (Participant, Investigator, Outcomes Assessor)
Primary purpose: Prevention