Ultrasound-guided Retrolaminar Block Versus Thoracic Epidural Analgesia for Pain Control Following Laparoscopic Cholecystectomy.

Background: Anesthesiologists are always looking for a regional analgesic technique which is easy, safe, has a low complication rate, and provides satisfactory analgesia. A retrolaminar block is a recent modified paravertebral technique for analgesia in  thoracoabdominal procedures with a local anesthetic injected at the retrolaminar site. It has the advantage of being safe and easy compared with traditional thoracic epidural analgesia but is still under investigation.

Objective: This study aimed to compare ultrasound-guided bilateral retrolaminar block with ultrasound-guided thoracic epidural analgesia for pain relief after laparoscopic cholecystectomy.

Study Design: A prospective randomized double-blinded clinical study.

Setting: Academic University Hospitals.

Methods: Fifty-two adult patients were randomly allocated into 2 equal groups at the end of the surgery: Group R (n = 26) received a bilateral ultrasound-guided retrolaminar block with 20 mL of 0.25% bupivacaine and 5 µg/mL adrenaline (1:200000) in each side. Group T (n = 26) received ultrasound-guided thoracic epidural analgesia with 20 mL of 0.25% bupivacaine and 5 µg/mL adrenaline (1:200000).

Results: The Numeric Rating Scale  scores both at rest and during cough were statistically significantly lower in Group R compared with Group T at 30 minutes and one hour postoperatively. The pain scores were statistically significantly lower for about 4 hours in Group R group compared with 6 hours in Group T. The time for the first call of nalbuphine was highly statistically significantly shorter in Group R group (233.04 ± 5.27 minutes) compared with Group T (353.77 ± 5.16 minutes) (mean difference -120.37, (95% CI,  -123.6 to -117.8) P < 0.001. The total amount of nalbuphine consumption in the first 12 hours was statistically significantly decreased in Group T (17.31 ± 5.52 mg) compared with Group R (27.69 ± 5.52 mg) (Mean difference 10.4, 95% CI  7.3-13.5), P < 0.001. The total number of patients who developed nausea and vomiting were statistically significantly greater in Group T (9 patients) compared with Group R group (3 patients), P = 0.04. Moreover, hypotension was statistically significantly more common among patients in Group T group (10 patients) compared with Group R (3 patients), P = 0.025. Both groups were comparable regarding patient satisfaction.

Limitations: There is limited literature in the field of the present study and sensory dermatome assessment, but this does not affect the results as we used an ultrasound-guided technique.

Conclusions: A single injection retrolaminar block provides adequate postoperative pain relief for about 4 hours compared with a single shot thoracic epidural that lasts about 6 hours. Patient satisfaction with both techniques was the same; about two-thirds of the patients were satisfied or very satisfied with either block.