Pre-Operative Single Shot Rectus Sheath Block
Pre-Operative Single Shot Rectus Sheath Block
Objectives The primary objective is to demonstrate that in patients undergoing major urologic
 surgery, Patient Controlled Analgesia (PCA) opioid consumption in the first 24 hours after
 surgery will be significantly less in patients who have had a single shot rectus sheath block
 pre-operatively in addition to a post-operative rectus sheath continuous block via surgically
 placed catheter versus those who only have post-operative rectus sheath continuous block.
 Secondary outcomes will be opioid requirement intra-operatively, Numerical Rating Scale (NRS)
 pain scores including maximum pain score in Post Anesthesia Care Unit (PACU) and score at 24
 and 48 hours, incidence and severity of nausea, number of vomiting episodes, sedation score,
 time to first bowel movement, time to first mobilization and duration of hospital stay.
Purpose: To improve analgesia and reduce opioid consumption in patients undergoing major
 urologic surgery.

 Hypothesis: Patients receiving pre-operative single shot rectus sheath blockade in addition
 to continuous rectus sheath catheters will use less PCA opioid in the first 24 hours
 post-operatively compared to patients receiving continuous rectus sheath blockade for major
 urologic surgery.

 Justification:

 The sensorimotor innervation of the anterior abdominal wall is supplied by the ventral rami
 of the thoracolumbar spinal (T7-L1) segmental nerves. The thoracolumbar nerves course along
 the anterolateral wall within the transversus abdominis plane (TAP), and continue
 anteromedially, before entering the lateral aspect of the posterior rectus sheath. The nerves
 provide both muscular and cutaneous branches to innervate the muscle fibers and overlying
 skin with innervation from both left and right nerves supplying the midline. Regional
 anesthesia techniques for the anterior abdominal wall include both TAP and rectus sheath
 blocks.

 The TAP block has been investigated extensively and shown to reduce opioid analgesia
 requirements post-operatively. The main difference between TAP block and rectus sheath block
 is that the rectus sheath block targets the nerves at a more anterior location. Bilateral
 rectus sheath nerve blocks are required to provide cover for midline incision and the
 investigators have previously described rectus sheath block with nerve catheter insertion
 under ultrasound guidance for midline laparotomy. A recent retrospective review from Dutton
 et al on the use of rectus sheath catheters for major urologic surgery reported that they
 offer an effective and safe method of peri-operative analgesia in patients undergoing major
 open urological pelvic surgery. Tudor et al demonstrated that rectus sheath catheters provide
 analgesia equivalent to that provided by epidurals following laparotomy for colorectal
 surgery.

 At the University of Alberta Hospital, patients having major urologic surgery e.g. cystectomy
 have surgically placed rectus sheath catheters sited at the end of the procedure as a
 standard of analgesia care. This is combined with patient-controlled analgesia (PCA) opioid
 as part of a multimodal approach to post-operative pain control.

 One disadvantage of surgically placed TAP and rectus sheath catheters is that they are
 inserted at the end of surgery. Therefore, the patient does not benefit from them
 intra-operatively and other methods of analgesia including opiates are required to reduce the
 sympathetic response to surgical stimulation and to prevent excessive immediate and early
 post-operative pain. The surgically placed rectus sheath catheters are sited during wound
 closure and then bolused with local anesthetic just prior to emergence so often the block is
 not fully established in the early post-operative period resulting in further opiate
 analgesia requirement.

 The primary objective is to demonstrate that in patients undergoing major urologic surgery
 PCA opioid consumption in the first 24 hours after surgery will be significantly less in
 patients who have had an ultrasound-guided single shot rectus sheath block pre-operatively in
 addition to a post-operative rectus sheath continuous block via surgically placed catheter
 versus those who only have post-operative rectus sheath continuous block.

 Secondary outcomes will be opiate requirement intra-operatively, Numerical Rating Scale (NRS)
 pain scores including pain score in PACU and score at 24 and 48 hours, incidence and severity
 of nausea, number of vomiting episodes, sedation scores, time to first bowel movement, time
 to first mobilization and duration of hospital stay.

 Research Methods: A randomized, double-blinded controlled trial.

 Subjects who meet eligibility criteria will be invited to participate in the study by the
 clinical care team or research assistant in the Preadmission Clinic. Informed consent will be
 obtained by the research assistant. Next, all eligible participants will be randomized to the
 treatment group i.e. pre-operative single shot bilateral rectus sheath blocks +
 post-operative catheters or the control group i.e. post-operative catheters.

 Randomization will be conducted through stratified-blocked randomization with varying blocks
 of 4 to 6 according to a schedule not known to the investigators using a computerized
 algorithm. The patient, intra-operative anesthetist, the surgeon and the assessor will be
 blinded to the randomization assignment.

 The treatment group will have pre-operative single shot bilateral rectus blocks with 20 ml of
 a ropivacaine / bupivacaine mixture per side. The control group will have a pre-operative
 sham subcutaneous injection of 1ml saline per side. Both groups will have bilateral rectus
 sheath catheters placed surgically at the end of the procedure. Under direct visualization,
 the surgeon will insert a standard nerve block catheter between the rectus abdominis muscle
 and the posterior rectus sheath lateral to the incision on both sides. The catheter will be
 fixed to skin via a specialized taping system. An infusion of 0.2% ropivacaine will be
 administered through the rectus sheath catheter (1ml / hour continuous infusion with 15 ml
 /hour bolus every 4 hours). All patients will receive an IV morphine or dilaudid PCA and
 adjunctive post-operative medication. Intra-operative morphine / dilaudid administered
 intra-operatively will be recorded as well as total morphine / dilaudid used in the first 24
 hours. Anesthesia technique will be standardized for short-acting opioid use i.e. fentanyl.
 Peri-operative multimodal analgesia adjuncts will include ketamine 0.2mg/kg and dexamethasone
 6mg. All patients will be pre-medicated with acetaminophen 1g and gabapentin 300mg
 pre-operatively.

 Primary and secondary outcomes will be collected by the study team from the patient chart and
 accompanying records and through patient interview. Continuous variables will be analyzed
 using t-tests and categorical variables will be analyzed using chi-squared test.
Inclusion Criteria:

 -  Adult patients over 18 years

 -  Undergoing major urological surgery

 -  Consent to a rectus sheath blockade as part of their postoperative management

 Exclusion Criteria:

 -  Patients under 18 years

 -  Local or systemic infection

 -  Patients who refuse consent

 -  Opioid tolerance

 -  History of chronic pain

 -  Psychiatric illness

 -  Allergy to local anesthetic.