Dr S Ramya , Dr G Shanmugapriya , Dr S Dinesh Kumar

BACKGROUND AND GOAL OF THE STUDY: The aim and objective of the study is to compare the duration of Postoperative Analgesia with Bupivacaine Vs Bupivacaine with Dexamethasone (perineurally or intravenously) in patients undergoing caesarean section using Ultrasound guided Transverse Abdominis Plane Block.
METHODS: We studied sixty antenatal patients those who meet inclusion criteria were randomized and allocated into three groups. After caesarean section under spinal anaesthesia , all the sixty patients received bilateral ultrasound guided transverse abdominis plane block when the spinal level regressed to T8 level, for post operative analgesia .Bupivacaine group (B) patients received 20 ml of 0.25 % Bupivacaine +2 ml of normal saline + 2 ml distilled water IV, Perineural Dexamethasone group (D1) patients received 20 ml of 0.25 % Bupivacaine +2 ml (8 mg) Dexamethasone + 2 ml distilled water IV and Intravenous Dexamethasone group (D2) patients received 20 ml of 0.25 % Bupivacaine +2 ml of normal saline + 2 ml (8 mg) Dexamethasone IV. Patients were evalauated for Demographic datas like Age, Weight, block grade, numerical pain scale for 24 hrs postoperatively, duration of analgesia, total dosage of tramadol used and Complications.
RESULTS: The duration of analgesia is prolonged in perineural Dexamethasone group (795 +/- 374.89 min) when compared to Bupivacaine group (513 +/-259.33 min) with a p value of 0.03 and also duration of analgesia is prolonged in intravenous Dexamethasone group (774 +/- 369.81 min) when compared to Bupivacaine group with a p value of 0.04 with no statistical significant difference between perineural and intravenous group ( p 1.00) . 
Total dose of rescue tramadol used is higher in Bupivacaine group (72.50+/- 30.24 mg) when compared to perineural Dexamethasone group (45 +/- 27.62 mg) in first 24 hours which is statistically significant with a p value of 0.01 and similarly total rescue tramadol dose used is lower in intravenous Dexamethasone group (47.50 +/-30.24 mg) compared to plain bupivacaine group with a p value of 0.03 with no statistical significance between perineural and intravenous Dexamethasone group (p value 1.00).No complications like nausea, vomiting, dizziness, femoral nerve palsy, pelvic hematoma, liver trauma etc. during first 24 hour study period.
CONCLUSION: The Dexamethasone in the dose of 8 mg added either Perineurally or Intravenously to 0.25 % Bupivacaine in Transverse abdominis plane block in cesaerean patients prolongs the duration of the block significantly and also reduces postoperative rescue analgesic requirement in the first 24 hours compared to plain Bupivacaine group.