Comparison of the analgesic efficacy of ultrasound-guided transmuscular quadratus lumborum block versus thoracic erector spinae block for postoperative analgesia in caesarean section parturients under spinal anaesthesia-A randomised study

Abstract

Background and aims: Truncal blocks play an important role in multimodal analgesia regimens to manage the postoperative pain after lower segment caesarean section (LSCS). This study was aimed to compare the analgesic efficacy of ultrasound (US)-guided transmuscular quadratus lumborum block (TQLB) and thoracic erector spinae plane block (TESPB) in parturients of LSCS done under subarachnoid block (SAB).

Methods: In a randomised and double blind study, 60 parturients scheduled for LSCS under spinal anaesthesia were randomly divided into two equal groups: group E (n = 30) and group Q (n = 30). After surgery, each parturient received either US guided bilateral TQLB (group Q) or TESPB (group E) with 20 ml 0.375% ropivacaine and 4 mg dexamethasone on each side. Assessments were done at 2, 4, 6, 8, 10, 12 and 24 h. The primary objective was to compare the duration of analgesia (first request to rescue analgesia) and the secondary objectives were to compare pain scores [numerical rating score (NRS)], total amount of tramadol consumption, incidence of nausea-vomiting, parturient satisfaction and other adverse effects in 24 hours postoperatively.

Results: The duration of analgesia (mean ± standard deviation) was comparable in group E (11.90 ± 2.49 h) and group Q (12.56 ± 3.38 h), P = 0.19. Pain scores (NRS) at rest and on movement were comparable at all time points of 2, 4, 6, 8, 10, 12, and 24 h (P > 0.05). The amount of tramadol used was comparable in group E and group Q (P = 0.48).

Conclusion: TESPB and TQLB are equally efficacious to provide postoperative analgesia after LSCS done under SAB when used as a part of multimodal analgesia.

Keywords: Analgesia; caesarean section; nerve block; post-operative pain; ultrasonography.

Figure 1

Consolidated Standards of Reporting Trials (CONSORT) flow diagram for enrolment, group allocation, follow-up and analysis. Gr-Q; TQLB (transmuscular quadratus lumborum block, Gr-E; TESPB (thoracic erector spinae plane block)

Figure 2

(a) The parturient in lateral position for TQLB; curvilinear probe (2-6 MHz) just above and posterior to the iliac crest with the needle entering from the posterior to the anterior direction. (b) Sonoanatomy, needle position and spread of local anaesthetic between quadratus lumborum and psoas major muscle. (c) Parturient is in left lateral position for TESPB; ultrasound probe position and block needle entry from lateral to medial direction, (d) Sonoanatomy of TESPB; needle at transverse process and spread of LA. TP-transverse process, SP-spinous process, ESP-erector spinae muscle, CTJ-costotransverse junction, QL – quadratus lumborum, PM – psoas major, LA – local anaesthetic

Figure 3

Kaplan–Meier graph showing the % of parturients in each group not requiring rescue analgesia (tramadol) over time (P = 0.18, log rank test). Group E (TESPB-Thoracic erector spinae plane block), Group Q (TQLB-Transmuscular quadratus lumborum block)