Design: Single-centre randomised controlled trial, three arms
Population: 150 women having elective caesarean under combined spinal-epidural
Primary outcome: 24-hour intravenous sufentanil consumption
Effect: I-TAP vs TAP: −11.4 µg (95% CI −17.6 to −5.3); I-TAP vs sham: −23.2 µg (95% CI −29.4 to −17.1)

A single-centre Chinese trial randomised 150 women having elective caesarean under combined spinal-epidural to one of three arms: an ilioinguinal-transversus abdominis plane (I-TAP) block, a conventional TAP block, or a sham block. Both active blocks used liposomal bupivacaine mixed with plain bupivacaine, and all women had epidural hydromorphone.

Over 24 hours, intravenous sufentanil use was about 11 micrograms lower with I-TAP than with a standard TAP block (95% CI 5 to 18 micrograms lower) and about 23 micrograms lower than sham. Pain scores, recovery-quality scores and maternal satisfaction favoured I-TAP, and adverse events were similar.

The rationale is that a standard TAP block can miss the L1 dermatome that the Pfannenstiel incision crosses. The trial is small and single-centre, and the drug used is costly and not widely stocked.

For units already using neuraxial morphine, the added gain from any plane block is modest. Where neuraxial opioid is not used, or a woman has a contraindication, a block that covers L1 is worth discussing with the anaesthetic team.

Neuraxial morphine or hydromorphone remains the base of post-caesarean analgesia
Consider a plane block when a neuraxial opioid cannot be given
Check whether your anaesthetic team covers the L1 dermatome when choosing a block
Liposomal bupivacaine is expensive and not routinely available in many Indian units; plain bupivacaine blocks are the practical option

Why it matters

It suggests a standard TAP block may leave the lower incision under-covered.

The statistics, in plain English

The confidence interval for the I-TAP versus TAP difference runs from 5 to 18 micrograms lower and does not cross zero, so the reduction is unlikely to be chance. Whether 11 micrograms of sufentanil is clinically meaningful is a separate question.