Spinal morphine is the mainstay of postcesarean analgesia.

Quadratus lumborum block has recently been proposed as an adjunct or alternative to spinal morphine.

The authors evaluated the analgesic effectiveness of quadratus lumborum block in cesarean delivery with and without spinal morphine.

Randomized trials evaluating quadratus lumborum block benefits in elective cesarean delivery under spinal anesthesia were sought.

Three comparisons were considered: spinal morphine versus spinal morphine and quadratus lumborum block; spinal morphine versus quadratus lumborum block; and no block or spinal morphine versus quadratus lumborum block. The two coprimary outcomes were postoperative (1) 24-h cumulative oral morphine equivalent consumption and (2) pain at 4 to 6 h.

Secondary outcomes included area under the curve pain, time to analgesic request, block complications, and opioid-related side effects.