Article Text
Abstract
Background and aims The ultrasound guided transversus abdominis plane (TAP) block was first described in 2007 by Hebberd, providing analgesia for the abdominal wall between T7-T11 depending on approach.
Prolonging the duration of the local anaesthetics (LA) in patients undergoing abdominal surgery is desirable as severe pain can develop on the first postoperative day after the effect of the local anaesthetic has worn off.
A number of LA adjuvants including magnesium sulphate [Indian J Anaesth, 2016; 60(3): 174–179], have been evaluated for their ability to prolong the duration of TAP block with varied results.
We performed a meta-analysis to find out if the addition of fentanyl prolongs the duration of sensory block therefore prolonging the time to first analgesia request after abdominal surgery.
Methods Pubmed, EMBASE, national and international conferences and google scholar searches using search terms fentanyl, transversus/transverse abdominal/abdominis plane block, ultrasound guided and adjuvant retrieved RCTs comparing LA versus LA + fentanyl for abdominal surgery. The data were analysed using RevMan software. The primary outcome was time to first analgesia request. Secondary outcomes included post-operative VAS scores and 24-hour morphine consumption.
Results 5 trials (334 patients) were included in the meta-analysis. The distribution of operation types included: laparoscopic cholecystectomies; ovarian cystectomies and caesarean sections. The addition of fentanyl does not prolong the time to first analgesia request, SMD (95%CI) 0.82[0.59, 1.06], P<0.00001. See figure 1.
Conclusions Regarding our primary outcome, the addition of fentanyl to TAP block does not prolong the time to first analgesia request compared to LA alone.