Comparison of Ultrasound-Guided Bilateral Erector Spinae Plane Block Versus Bilateral Rectus Sheath Block in Adults Undergoing Major Abdominal Surgery
Condition: Pain; Postoperative
Study type: Interventional

Summary: 
      This randomized, controlled study is designed to assess the quality of analgesia provided by
      ultrasound guided ESPB versus RSB in adults undergoing major abdominal surgery.
    

Detailed description: 
      Introduction:

      Regional anesthesia is a key component of opioid-sparing multimodal analgesia after major
      abdominal surgery as it improves recovery such as return of bowel function and early
      ambulation. Continuous epidural local anesthetic infusion is a common analgesic technique but
      comes with the side effect of hypotension and potential leg weakness and rarely, epidural
      abscess or hematoma. The rectus sheath block (RSB) has been used for postoperative analgesia
      in surgical procedures involving a vertical midline laparotomy incision as well as for
      laparoscopic procedures. In this block the ventral rami of the seventh intercostal nerve up
      to the subcostal nerve, which supply the rectus abdominis muscle and overlying skin, are
      blocked.

      Recently, the erector spinae plane block (ESPB) has gained wide attention due to its
      simplicity and potential uses in truncal procedures. This paraspinal plane block is performed
      by injecting local anesthetic between the erector spinae muscles and transverse processes and
      is thought to work by blocking the dorsal and ventral rami of the thoracic spinal nerves.
      Injections at various thoracic levels have been described in case reports with satisfactory
      postoperative analgesia for breast, thoracic and abdominal procedures. Comparison of
      post-operative pain management of both erector spinae plane block and rectus sheath block in
      adults undergoing major abdominal surgery for has not been investigated before.

      Hypothesis:

      It is hypothesized that ESPB is more effective in postoperative analgesia following major
      abdominal surgeries with minimal motor affection and postoperative morphine consumption
      compared to RSB block.

      2. Study Protocol:

      On arrival of the patients to anesthesia room, patients will be secured with 20-gauge
      intravenous cannula and will receive midazolam 0.02mg/kg intravenous (IV), ondansetron (4 mg
      slowly IV).

      Monitoring will include ECG, non-invasive arterial blood pressure, and pulse oximetry (SpO2).

      All patients will receive a standardized anesthetic technique for induction with 2mcg/kg
      fentanyl, 2-3 mg/kg propofol, and 0.5 mg/kg atracurium. Mechanical ventilation will be
      adjusted to maintain an end tidal CO2 between (30 - 40 mmHg). Maintenance will be achieved
      with oxygen/air with isoflurane 1.2% and atracurium infusion at a dose of 0.5 mg/kg/h.

      Following induction of anesthesia patients will be divided into two equal groups; Group 1
      will receive pre-incisional ultrasound (US)-guided Bilateral RSB blocks using 20-ml volume of
      bupivacaine 0.25% for each side, and group 2 will receive pre-incisional ultrasound
      (US)-guided Bilateral ESPB using 20-ml volume of bupivacaine 0.25% for each side.

      Group 1(RSB):

      After preparing the skin with povidone iodine, a high frequency (5-10 MHz) ultrasound probe
      (S-NerveTM; SonoSite Inc., Bothell, WA, USA) will be placed in a longitudinal orientation
      above the level of the umbilicus with the Patient in the supine position. After identifying
      the rectus abdominis muscle, A 22 G echogenic needle using the in plane technique will be
      inserted just below the costal margin at an angle of approximately 45 degrees to the skin,
      then, a total of 20 ml of 0.25% bupivacaine will be injected into the plane between the
      rectus muscle and posterior rectus sheath. Negative aspiration will be confirmed every 5 ml.
      The block will then be repeated on the other side.

      Group 2 (ESPB):

      After induction of anesthesia; the patient will be positioned on the lateral position. The
      skin will be prepared with povidone iodine, and a high frequency (5-10 MHz) ultrasound probe
      (S-NerveTM; SonoSite Inc., Bothell, WA, USA) will be placed in a transverse orientation on
      the T9 spinous process which will be located by palpating and counting down from the C7
      spinous process. The tip of the T9 transverse process will be identified and centred on the
      ultrasound screen, the probe will then be rotated into a longitudinal orientation to produce
      a parasagittal view, visible superﬁcial to the acoustic shadows of the transverse processes:
      skin and subcutaneous tissue; trapezius; and erector spinae muscle .Correct location of the
      needle tip in the fascial plane deep to erector spinae muscle is conﬁrmed by injecting 0.5-1
      ml saline and seeing the ﬂuid lifting the erector spinae muscle off the transverse process
      while not distending the muscle. A total of 20 ml of 0.25% bupivacaine will then be injected
      into the ESP of both sides. Negative aspiration will be confirmed every 5 ml].

      Postoperative pain management:

      Postoperatively, patients will receive 1 g paracetamol every 6 h and 30 mg ketorolac every 12
      h.

      If the visual analogue scale (VAS) is ≥ 4, a morphine increment (2-3 mg) IV that could be
      repeated every 5 minutes with a maximum dose of 15 mg per 4 hours or 45 mg per 24 hours will
      be added to maintain a resting VAS at <4 and the total 24 hours morphine consumption will be
      recorded.
    

Intervention name(s): Ultrasound guided Rectus sheath block vs Erector spinae plane block
Intervention type(s): Device
Intervention description(s): Ultrasound guided Rectus sheath block vs Erector spinae plane block
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: Study will be conducted on 60 adults aged from 18 to 60 years presented for major abdominal surgeries (open colorectal resections or major ventral hernia repair) at general surgery operating theatres, Cairo university hospitals.
Patients will be divided into two equal groups; rectus sheath block group RSB (n=30) and erector spinae plane block group ESPB (n=30).
Masking: Triple (Participant, Care Provider, Outcomes Assessor)
Primary purpose: Prevention
Keywords: erector spinae; ultrasound; rectus sheath; pain