Pain management after open inguinal hernia repair: an updated systematic review and procedure-specific postoperative pain management (PROSPECT/ESRA) recommendations

Background : Open inguinal hernia repair can be associated with moderate-to-severe postoperative pain, which can delay return to activities of daily living. The aim of this systematic review was to update the available literature and develop recommendations for optimal pain management after open inguinal hernia repair. A systematic review utilizing PROcedure SPECific Postoperative Pain ManagemenT (PROSPECT) methodology was undertaken.

Methods : Randoinised controlled trials published in the English language between January 1st 2009 and August 31st 2019. evaluating the effects of analgesic, anesthetic, and surgical interventions were retrieved from MEDLINE, EMBASE and Cochrane Databases. Of 203 eligible studies identified, 37 studies met the inclusion criteria.

Results : Interventions that improved postoperative pain relief included paracetamol and nonsteroidal anti-inflammatory drugs or cyclooxygenase-2 selective inhibitors, as well as local anesthetic infiltration and regional analgesia techniques such as ilio-hypogastric/ilio-inguinal nerve blocks and transversus abdominis plane blocks. Although effective, epidural analgesia or paravertebral blocks are considered invasive and harmful, and thus not recommended. Insufficient evidence was found for psoas block, extended release local anesthetics, wound infiltration using non-steroidal anti-inflammatory drugs. clonidine or opioids, topical conventional nonsteroidal anti-inflammatory drugs, systemic clonidine, corticosteroids and ketamine, intravenous lidocaine infusion, cryoanalgesia techniques, and nerve section. Inconsistent evidence was found for the use of gabapentinoids.

Conclusion : The analgesic regimen for open inguinal hernia repair should include paracetamol and nonsteroidal anti-inflammatory drug or cyclooxygenase-2 selective inhibitor administered pre-operatively or Ultraoperatively and continued post-operatively. In addition, local anesthetic infiltration and/or a regional analgesia technique (ilio-inguinal nerve blocks or transversus abdominis plane blocks), with opioids used as rescue analgesics. Further studies are required to assess the role of novel regional analgesic techniques such as erector spinae blocks and to confirm the influence of the recommended analgesic regimen on postoperative pain relief in an enhanced recovery setting.