Ultrasound guided rectus sheath block and oblique subcostal transversus abdominis plane block for perioperative analgesia in midline incision abdominal surgery: A double blind, prospective, randomized comparative study.

·      Patients undergoing abdominal surgical procedures with midline incision experience significant pain.

·      Postoperative pain therapy is a key element of efficient postoperative care. Inadequate pain control may delay the recovery of patients, prolong hospital stay, increased expenses and may precipitate chronic pain.

·      Historically, pain control is accomplished through opioid administration, which is associated with side effects such as sedation, respiratory depression, pruritus, hallucinations, postoperative nausea and vomiting (PONV). Administration of multimodal analgesics could limit the excessive use of systemic opioid analgesia.

·      Epidural analgesia remains the gold standard for pain control for abdominal surgical procedures. .However,  epidural  analgesia  complications include  hypotension,  bradycardia,  dural  puncture, spinal  infection, immobilization due to motor block, urine retention and rarely neurological damage.

·      Due to these risks, alternative approaches to traditional anesthetic techniques should also be assessed.The idea of oblique subcostal transversus abdominis plane block (OSTAPB) and rectus sheath block is to anesthetize part of or the entire abdominal wall instead of using intrathecal or epidural techniques.

·      These blocks may also be effective in reducing postoperative pain in midline incisional abdominal surgery as an alternative method of epidural analgesia in anticoagulated patients.

·      The rectus sheath block was first described by Schleich in 1899 as a means of facilitating surgery involving the anterior abdominal wall in adults.It was initially used for abdominal wall muscle relaxation and analgesia during midline laparotomy by blocking the terminal branches of the9th, 10th and 11th intercostal nerves located in the space between the rectus abdominis muscle and its posterior rectus sheath. It has been used for postoperative analgesia extending along the midline for upper abdominal surgeries, abdominal gynecological procedures, and abdominoplasty.

·      The oblique subcostal transversus abdominis plane block (OSTAPB) is a regional anesthetic technique that targets the injection of the local anesthetic (LA) in the neurovascular plane between the rectus abdoiminis muscle and transversus abdominis muscle.Hebbardet al. (2010) described the US-guided continuous oblique subcostal TAP block. With a single oblique subcostal TAP block (OSTAPB) injection, the sensory block extends to the thoracolumbar nerves (T6-L1) making the block beneficial for midline abdominal incisions also.