Continuous serratus intercostal interfacial plane block for perioperative analgesia in upper abdominal surgeries, a prospective randomized controlled study

Upper abdominal incisions are associated with substantial degree of postoperative pain. Pain after upper abdominal surgeries is associated with increased postoperative morbidity especially pulmonary complications1. Different analgesic modalities were used to control pain after abdominal surgeries including epidural block, abdominal wall block and systemic analgesics2.Epidural technique is the gold standard for analgesia after upper abdominal surgeries. However, technical difficulties in some patients, hemodynamic effects, relative contraindications in patients with coagulopathy and cardiovascular disease can be considered a technique limitation3. As alternative, interfacial plane blocks were recommended as an alternative technique, but with abdominal incision and surgical trauma, the ambiguity of the Sonographic view and the fear of iatrogenic injury to viscera and neurovascular bundles complicated the procedure4.Recently, serratus intercostal interfacial block was reported to be effective analgesic technique for upper abdominal surgeries5–7. Advantages of serratus anterior block included easiness of the technique, and possibility of block in supine position. The diffusion of LA in this fascial plane, between the external intercostal and the serratus anterior muscle, blocks the cutaneous branches of the intercostal nerves, providing adequate analgesia for upper abdominal surgery. Few studies investigated the analgesic effect of the new block technique and fewer used continuous techniques for control of pain after abdominal surgeries8–10.In this prospective randomized study, we will investigate the perioperative analgesic effect of serratus intercostal interfacial plan block after elective open abdominal surgeries. We hypothize that the serratus intercostal interfacial plan block will offer a satisfactory analgesic option after open abdominal surgeries avoiding technical difficulties of other interfacial plane blocks with better patient experience. The primary