Transversus Abdominis Plane Block Versus Wound Infiltration for Postcesarean Analgesia

Performed at the L3-4 or L4-5 interspace using 27- or 25-gauge spinal needle.

Bupivacaine 12.5 mg will be administered in the subarachnoid space.

Fentanyl 15 µg will be administered in the subarachnoid space.

Lower segment cesarean section using the Pfannenstiel incision and exteriorization of the uterus.

30 mL bupivacaine 0.25% will be injected subcutaneously in the surgical wound (15 mL on the upper and lower sides) by the obstetrician before skin suturing.

Sham procedure will be performed after surgery by moving the ultrasound probe and pressing a covered spinal needle on both sides of the patients' abdomen.

Bilateral ultrasound-guided TAP block using 20 mL bupivacaine 0.25% on each side. A 7-12 MHz linear array probe and 22-gauge needle will be used. The probe will be placed transversely above the iliac crest in the anterior axillary line and the needle will be introduced in-plane with the probe from medial to lateral.

IV ketorolac 30 mg/8 h starting at the end of surgery.

Oral paracetamol 1 gm/8 h starting 4 h after surgery.

Intravenous fentanyl: bolus dose = 20 µg, lockout interval = 7 min, 4-h dose limit = 200 µg, with no background infusion.