Clonidine/Naltrexone

Open inguinal herniorrhaphy is a common outpatient surgical procedure. Post-operative pain can be a significant hindrance to discharge from the post anesthesia care unit. Pain can be treated with opioid therapy, but the literature supports that these agents are known to create or exacerbate adverse effects and complications, including post-operative nausea and vomiting, hypoxia, and urinary retention. In contrast, analgesia provided by regional anesthesia results in a decreased risk of the aforementioned complications.1 Because of this, various regional anesthetic techniques have been developed to provide analgesia following open herniorrhaphy. One technique is a combined ilioinguinal and iliohypogastric nerve block (IINB), which has been shown to decrease the initial pain after inguinal herniorrhaphy.2 The quadratus lumborum block (QLB) is a newer regional anesthetic technique that we think could be as effective as IINB at providing pain control following open herniorrhaphy. Additionally, because local anesthetic injected during a QLB has the potential to spread cranially into the thoracic paravertebral space following its lumbar deposition it could lead to alleviation of both somatic and visceral pain.3 This might therefore improve the quality and or duration of analgesia as compared to the IINB. To the best of the author's knowledge there has been no investigation comparing the efficacy, with regards to post-operative pain management, between IINB and QLB.