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Randomized Clinical Trial Comparing Laparoscopic Versus Ultrasound-Guided Transversus Abdominis Plane Block in
Karen N Zaghiyan1, Brian J Mendelson2, Matthew R Eng2
1Division of Colon and Rectal Surgery, Cedars-Sinai Medical Center, Los Angeles, California.
Background:
Transversus abdominis plane block may improve analgesia after colorectal surgery; however, techniques remain unstandardized and results are conflicting.
Objective:
The purpose of this study was to compare laparoscopic and ultrasound-guided transversus abdominis plane block with no block in minimally invasive colorectal surgery.
Design:
This was a randomized controlled trial.
Settings:
The study was conducted at an urban teaching hospital.
Patients:
Patients undergoing laparoscopic colorectal surgery were included.
Interventions:
The intervention included 2:2:1 randomization to laparoscopic, ultrasound-guided, or no transversus abdominis plane block.
Main Outcome Measures:
Morphine use in the first 24 hours after surgery was measured.
Results:
The study cohort included 107 patients randomly assigned to laparoscopic (n = 41), ultrasound-guided (n = 45), or no transversus abdominis plane block (n = 21). Mean age was 50.4 years (SD ± 18 y), and 50 patients (47%) were men. Laparoscopic transversus abdominis plane block was superior to ultrasound-guided (p = 0.007) and no transversus abdominis plane block (p = 0.007), with median (interquartile range) total morphine used in the first 24 hours postoperatively of 17.6 mg (6.6-33.9 mg), 34.0 mg (16.4-44.4 mg), and 31.6 mg (18.4-44.4 mg). At 48 hours, laparoscopic transversus abdominis plane block remained superior to ultrasound-guided (p = 0.03) and no transversus abdominis plane block (p = 0.007) with median (interquartile range) total morphine used at 48 hours postoperatively of 26.8 mg (15.5-45.8 mg), 44.0 mg (27.6-70.0 mg), and 60.8 mg (34.8-78.8 mg). Mean hospital stay was 5.1 ± 3.1 days without any intergroup differences. Overall complications were similar between groups.
Limitations:
Treatment teams were not blinded and there was operator dependence of techniques and variable timing of the blocks.
Conclusions:
Laparoscopic transversus abdominis plane block is superior to ultrasound-guided and no transversus abdominis plane block in achieving pain control and minimizing opioid use in the first 24 hours after colorectal surgery. A large, multicenter, randomized trial is needed to confirm our findings. See Video Abstract at http://links.lww.com/DCR/A822.
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