We read with interest, the audit by Drs Hebbard et al [1] regarding TAP blocks for Caesarean sections. We may have answers to both your queries regarding TAP blocks. We have been performing TAP blocks in our obstetric unit since November 2007 using a technique identical to yours. Prior to instituting these blocks in obstetrics, patients undergoing Caesarean section in our unit traditionally received intrathecal fentanyl rather than morphine / diamorphine (due to logistical issues regarding availability of these drugs for intrathecal use). Postoperative analgesia was achieved using a multimodal regime consisting of IV PCA morphine, regular cocodamol, PRN diclofenac and tramadol. We added TAP block to our regime to improve the quality of postoperative analgesia and also to avoid the side-effects of nausea and vomiting associated with IV PCA morphine.  

In a subsequent prospective audit, similar to yours [2], we compared the analgesic requirements of 20 patients having LSCS and TAP blocks with 20 patients without TAP blocks. Our audit data included VAS pain scores and 24 hr IV PCA morphine usage in both groups. The mean (SD) morphine usage was significantly lower in patients having TAP blocks (30 (7.05) vs 59 (2.1) mg); VAS scores were also lower in the TAP block group (1.5 vs 4)]. TAP blocks are now a part of our standard postoperative analgesic regime following elective LSCS.

LSCS patients with TAP blocks sometimes require rescue doses of parental morphine postoperatively, but generally patients are mobile with good pain relief from oral analgesia once the effects of the spinal wear off. We also have considerable experience of TAP catheters within our hospital for patients undergoing major general/gynaecological surgery (in whom epidurals are contra-indicated), but feel they are not required in our LSCS patients since their pain is well managed with oral analgesia by the time the block has worn off.

FJE Jacintha

RJVickers

Queens’ Hospital NHS Trust,

Burton on Trent, UK

References

1. Hebbard P, Royse C. Audit oftransverse abdominus plane block for analgesia following caesarean section.Anaesthesia 2008; 63: 1382.

2. Jacintha FJE, VickersRJ, Stewart C. Introduction oftransversus abdominis plane block for post caesarean section analgesia: a substitute or a supplement to patient-controlled opioids? IJOA 2008; 17: S3-P46.