Ultrasound-guided transversus abdominis plane block for analgesia after Caesarean delivery.
BACKGROUND
The landmark-guided transversus abdominis plane (TAP) block is an effective method of providing postoperative analgesia in patients undergoing lower abdominal surgery. We evaluated the analgesic efficacy of the ultrasound (US)-guided TAP block in patients undergoing Caesarean delivery.


METHODS
A randomized, double-blind, placebo-controlled trial was performed at a tertiary maternity hospital. Fifty women undergoing Caesarean delivery received bilateral US-guided TAP blocks with either ropivacaine 0.5% or saline. All participants received a spinal anaesthetic with bupivacaine and fentanyl, followed by postoperative acetaminophen, non-steroidal anti-inflammatory drugs, and patient-controlled i.v. morphine without long-acting intrathecal opioids. Each patient was assessed 24 h after delivery for morphine usage, average pain score, nausea, vomiting, pruritus, drowsiness, and satisfaction with pain relief.


RESULTS
Forty-seven participants completed the trial, 23 in the active group and 24 in the placebo group. Total morphine use in 24 h was reduced in the active group (median 18.0 mg) compared with the placebo group (median 31.5 mg, P<0.05). The active group reported improved satisfaction with their pain relief measured by visual analogue scale compared with the placebo group (median 96 vs 77 mm, P=0.008). Fewer patients required antiemetics in the active group (P=0.03). There were no local complications attributable to the TAP block, but one participant had an anaphylactoid reaction after ropivacaine injection.


CONCLUSIONS
The US-guided TAP block reduces morphine requirements after Caesarean delivery when used as a component of a multimodal analgesic regimen. Registered with the Australia New Zealand Clinical Trials Registry ACTRN12608000540314. URL: http://www.anzctr.org.au/trial_view.aspx?ID=83176.
Belavy
D
D
Department of Anaesthesia, Mater Misericordiae Health Services, Raymond Terrace, South Brisbane, Qld, Australia. david@belavy.com
Cowlishaw
P J
PJ
Howes
M
M
Phillips
F
F
D000009:Abdominal Muscles / Q000000981:diagnostic imaging; D000328:Adult; D016362:Analgesia, Obstetrical / Q000379:methods*; D016058:Analgesia, Patient-Controlled / Q000379:methods; D000701:Analgesics, Opioid / Q000008:administration & dosage; D000773:Anesthesia, Obstetrical / Q000379:methods; D000775:Anesthesia, Spinal; D002585:Cesarean Section; D003131:Combined Modality Therapy; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D009020:Morphine / Q000008:administration & dosage; D009407:Nerve Block / Q000009:adverse effects / Q000379:methods*; D010149:Postoperative Pain / Q000517:prevention & control*; D011247:Pregnancy; D018084:Ultrasonography, Interventional / Q000379:methods*; D055815:Young Adult
D000701:Analgesics, Opioid; D009020:Morphine