Improved perioperative analgesia with ultrasound-guided ilioinguinal/iliohypogastric nerve or transversus abdominis plane block for open inguinal surgery: a systematic review and meta-analysis of randomized controlled trials

Abstract

[Purpose] Ultrasound-guided ilioinguinal/iliohypogastric (II/IH) nerve and transversus abdominis plane (TAP) blocks have been increasingly utilized in patients for perioperative analgesia. We conducted this meta-analysis to evaluate the clinical efficacy of ultrasound-guided II/IH nerve or TAP blocks for perioperative analgesia in patients undergoing open inguinal surgery. [Subjects and Methods] A systematic search was conducted of 7 databases from the inception to March 5, 2015. Randomized controlled trials (RCTs) comparing the clinical efficacy of ultrasound-guided vs. landmark-based techniques to perform II/IH nerve and TAP blocks in patients with open inguinal surgery were included. We constructed random effects models to pool the standardized mean difference (SMD) for continuous outcomes and the odds ratio (OR) for dichotomized outcomes. [Results] Ultrasound-guided II/IH nerve or TAP blocks were associated with a reduced use of intraoperative additional analgesia and a significant reduction of pain scores during day-stay. The use of rescue drugs was also significantly lower in the ultrasound-guided group. [Conclusion] The use of ultrasound-guidance to perform an II/IH nerve or a TAP block was associated with improved perioperative analgesia in patients following open inguinal surgery compared to landmark-based methods.

Femoral Nerve Palsy Following Landmark Based Ilioinguinal-Iliohypogastric Nerve Block: Case Report and Safety Review

“…Recently, there has been an increased emphasis on adequate pain management with minimal opioid administration [5][6][7][8][9][10]. This is particularly important with an aging population who are prone to the adverse effects of opioids including somnolence, cognitive impairment, nausea, vomiting, and respiratory depression [11].…”

“…Complications following II/IH-NB are 4.5-9% [3, 9, 12] with serious complications rarely reported. In addition to transient FNP, complications include trauma to blood vessels, pelvic hematoma, intravascular injection, urinary retention, and bladder/enteric penetration [3,5,9,12]. Practitioner experience and modality of administration have been associated with complications and failure of NB to provide adequate analgesia [5,13].…”

“…Inadequate analgesic rates of 28-45% are reported [5,7,13]. Suggested mechanisms include unpredictable nerve course, inaccuracy of tactile clicks, user experience and anatomic muscular variation [5].…”

“…Inadequate analgesic rates of 28-45% are reported [5,7,13]. Suggested mechanisms include unpredictable nerve course, inaccuracy of tactile clicks, user experience and anatomic muscular variation [5]. The combined thickness of the internal oblique and transversus abdominis muscles, which constitutes the desired landing zone, is less than 5 mm in cadaveric studies [2].…”

“…These include a fan distribution of infiltration, multiple site injection, and direct visualization [5,7,10,13].…”