Effect of transverse abdominal plane block use in post-caesarean analgesia: A randomised double blind study

In cesarean delivery, TAP block represents a convenient primary analgesic for women not receiving neuraxial morphine for any reason. TAP block is an assisting analgesic technique used to decrease either the use of opioids during the intraoperative period or the use of systemic analgesics for postoperative pain management. The TAP block is a field block of the thoracolumbar nerves, running in the fascial plane between the internal oblique muscle and the transversus abdominis muscles. The anterior primary rami course between the internal oblique and the transversus abdominis muscles and subsequently branch into the lateral and anterior cutaneous nerves at approximately the midaxillary line.

Study procedure:

 This will be a double blinded study where the study participant and the investigator is blinded. Anaesthetist who will perform the block will not be blinded.

After obtaining clearance from institutional ethical committee, Study participants admitted for Caesarean section under spinal anaesthesia will be randomly allocated at admission to either the TAP block group or the control group by sealed opaque envelope method by the staff nurse of the ward. Consent will be obtained after informing about the study from both groups.

The TAP block group will receive landmark-orientated, bilateral TAP block in the triangle of Petit by loss of resistance method after closure of the abdomen by anaesthetist. Drug used will be bupivacaine 0.25% 20 ml on each side. Control group will receive placebo- 20 ml 0.9% normal saline bilaterally at the same landmark.

 Intra operative monitoring of blood pressure , pulse rate, saturation, will be done for both groups.

 After completion of the procedure, study participants will be  shifted to the post anaesthesia care unit  before transferring them to the ward.

Demand for first rescue analgesia will be studied in both groups. Both the groups will receive a standard post-operative analgesic regimen with 1gm/100ml paracetamol every 12 h and 50 mg IV tramadol on demand for breakthrough pain.

All the subjects will be assessed at  2, 4, 8, 12, 18 & 24 h after surgery for pain at rest & on movement.

All the subjects will be asked to rate their pain at rest and on movement using a visual analogue scale (VAS) with ‘0’ representing no pain and ‘10’ being the worst imaginable pain. Supplemental analgesia (50 mg tramadol IV) will be administered if VAS > 4 on movement or if the mother demanded for it.

If no supplemental analgesia was given within 12 h of surgery, regular dose of paracetamol will be administered to both groups.

Time at first ambulation will be studied in both groups.

Total doses of tramadol and paracetamol given at the end of 24 hours in both groups will be assessed.

At the end of the study, mothers will be asked to rate their satisfaction with the pain management in a 3-point scale (1- dissatisfied, 2- satisfied, 3- highly satisfied)

 Recorded data will be analysed with the help of statistician.

 After ethical committee clearance from the institution, this trial will be registered witrh central trial registry of India