The Feasibility of Performing Erector Spinae (ESP) Nerve Block in Bariatric Patients; a Case Series Study
Status:
Withdrawn
Trial end date:
2022-06-01
Target enrollment:
Participant gender:
Summary
This study is a pilot study to assess the effectiveness of erector spinae (ESP) nerve blocks
for postoperative pain control following bariatric surgery. Currently, there are mainly case
series/pilot studies describing the use of ESP nerve blocks for postoperative pain control in
abdominal procedures; of these only one uses this treatment modality for bariatric
procedures. The population undergoing bariatric surgery poses specific challenges to
postoperative pain management. They often have comorbid obstructive sleep apnea, which puts
them at greater risk for ventilatory depression when treated with parenteral opioids. This
risk can be reduced with regional techniques. The ESP nerve blocks provide visceral and
somatic pain coverage as opposed to the more commonplace transversus abdominis plane nerve
block which only provides somatic coverage. This means that the ESP nerve blocks will cover
incisional pain as well as the discomfort associated with the pain from the procedure itself.
This study intends to build on current knowledge by proving that the use of ESP in the
post-operative are providing a significant reduction in pain scores as well as reducing the
need for parenteral opioids. Thus, decreasing the risk of postoperative ventilatory
complications.
In preparation for this study, three pilot studies were reviewed. The studies assessed the
usefulness of ESP nerve blocks on patients undergoing abdominal surgery. Single-shot
bilateral ESP blocks were performed in the first two studies. One of the studies, patients
undergoing ventral hernia repair and the other for patients undergoing bariatric surgery. The
third pilot study used bilateral ESP blocks followed by a continuous infusion on one patient
undergoing an open prostatectomy with bladder reconstruction. All the ESP blocks were placed
preoperatively at the T7 transverse process. In the studies using a single shot technique
20-30 ml of ropivacaine 0.5% was used. For the continuous ESP catheter an initial bolus of
bupivacaine 0.25% 10 mls followed by continuous infusion rate of 6 ml/hr bilaterally. All
showed a significant reduction numerical rating scale (NRS) as a primary outcome. The
secondary outcome of reduced 24-hour parenteral opioid consumption was also achieved by all
three studies.