Effect of dexamethasone as an adjuvant to levobupivacaine in transversus abdominis plane (TAP) block for postoperative analgesia in subjects undergoing lower segment cesarean section

Abstract

Background: Inadequate pain relief after caesarean section is a common problem in every part of the world. Transversus abdominis plane (TAP) block provides adequate post-operative pain relief following abdominal surgeries. TAP block duration is limited to effect of administered local anesthetics. Hence, adjuvant medications are added to local anaesthetic (LA) to prolong the effect of TAP block. The primay objective of this study was to analyse the analgesic effect of dexamethasone added to levobupivacaine in comparison with analgesic effect of levobupivacaine alone in TAP block. The secondary objectives are to analyse the number of supplemental analgesic requirements in the first 24 hrs after surgery and to analyse the duration of postoperative analgesia which is time to first analgesic request from the time of TAP block. Methods: 116 women scheduled for lower segment cesarean section (LSCS), belonging to ASA physical status 2 or 3, aged between 18 and 35 years, under SAB were recruited. Ultrasonogram (USG) guided TAP block was performed on each side after the completion of the surgery. Subjects in group L (n = 58) received TAP block on each side with 20 ml of 0.375% levobupivacaine and group LD (n = 58) with 19 ml of 0.375% levobupivacaine + 1ml (4mg) of dexamethasone. They were evaluated for pain at 10min, 30min, 45min, 1hour, 2hrs, 4hrs, 8hrs, 12hrs and 24hrs after the block using visual analog scale (VAS) score. Duration of postoperative analgesia and requirement of rescue analgesia were also analysed. Results: The post-operative visual analogue scale (VAS) scores were lower in group LD at 8, 12 and 24 hrs (p < 0.05). Mean duration of analgesia was significantly prolonged in group LD with lesser requirement of rescue analgesics (p < 0.05) up to 24 hrs. Conclusion: Dexamethasone (4 mg) as an adjuvant to levobupivacaine in USG guided TAP block reduces post-operative pain scores prolongs the duration of analgesia and decreases demands for rescue analgesics

Keywords

• levobupivacaine
• dexamethasone
• ultrasound guided block
• transversus abdominis plane block
• lower segment caesarean section
• visual analogue scale