IINB vs. QLB for Elective Open Inguinal Herniorrhaphy
Condition: Nerve Block; Herniorrhaphy; Regional Anesthesia
Study type: Interventional
Phase: Phase 2

Summary: 
      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.
    

Detailed description: 
      This study will be a double-blinded prospective randomized controlled equivalency trial
      comparing QLB to IINB. Patients presenting for unilateral open inguinal herniorrhaphy who
      agree to participate in the study and do not meet exclusion criteria will be randomized to
      either receiving an IINB or a QLB for post-operative analgesia. After performing a timeout,
      applying monitors (ECG, capnography, Sp02, non-invasive blood pressure), and confirming all
      paperwork per the usual pre-procedural check list the study participants will be administered
      procedural sedation (fentanyl and midazolam) to comfort as well as supplemental oxygen. The
      anatomy of both block sites will be identified by palpation of landmarks, labeling of
      structures with a skin marking pen, and visualization under ultrasound guidance. Both sites
      will be administered a small skin wheal of lidocaine 1% at the site the block needle would be
      introduced into the skin. Our intent with regards to administering a local anesthetic skin
      wheal is to increase our success in blinding the patient to which block was actually
      performed. A regional anesthetic block will only be performed at the randomized block site
      (IINB vs. QLB). After 15-30 minutes post block or post operatively the block will be assessed
      for success. Loss of cold sensation in the area of the surgical site would be indicative of
      block success. The patient will then proceed to the operating room and receive a general
      anesthetic with the final details of that anesthetic to be determined by the anesthesiologist
      responsible for the patient in the operating room. We will ask the operating room
      anesthesiologist and surgeon to avoid administration of medications that would confound our
      results. Specifically, no additional local anesthetic is to be injected at the incision site,
      no long acting opioids (hydromorphone, morphine, methadone etc…), dexamethasone or ketamine.
      After completion of the procedure the patient will recover in the post anesthesia care unit
      (PACU) where the participant will recover as per the usual process. The patient's discharge
      disposition will be at the discretion of the surgeon and anesthesiologist responsible for the
      participant's PACU care. The patient will be provided a diary that the participant will
      complete at 8hrs and 24hrs post block that will help the participant compile the data
      pertinent to the investigators primary and secondary outcomes. This diary should take no more
      than a minute or two for each sampling time. Participants will receive two phone calls at
      home to obtain this data at 8hrs and 24hrs.
    

Intervention name(s): Ilioinguinal / Iliohypogastric Block; Quadratus Lumborum Block; Bupivacaine 0.25%; Epinephrine 1:200k; Clonidine 1.66mcg/cc
Intervention type(s): Procedure; Procedure; Drug; Drug; Drug
Intervention description(s): Patients randomized to this arm will receive 25cc's of Bupivacaine 0.25% + Epinephrine 1:200k + Clonidine 1.66mcg/cc administered via an ultrasound guided ilioinguinal / iliohypogastric block technique.; Patients randomized to this arm will receive 25cc's of Bupivacaine 0.25% + Epinephrine 1:200k + Clonidine 1.66mcg/cc administered via an ultrasound guided quadratus lumborum block technique.; Administered as part of the local anesthetic mixture; Administered as part of the local anesthetic mixture; Administered as part of the local anesthetic mixture
Intervention MeSH terms: Clonidine; Epinephrine; Bupivacaine
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Triple (Participant, Investigator, Outcomes Assessor)
Primary purpose: Treatment