VOLUME 29, Issue 1

Epidural analgesia has a long history of use and benefit for a wide variety of thoraco-abdominal surgical procedures, in addition to labor analgesia. The ability to provide continuous analgesia for several days while decreasing the amount of opioids needed for pain management is invaluable. A review by Rodgers in 2000 showed that neuraxial anesthesia helped decrease the odds of deep venous thrombosis, pulmonary embolism, and transfusion requirements when compared to general anesthesia [1]. A recent Cochrane review by Guay showed a reduction in 30-day mortality of patients receiving neuraxial versus general anesthesia in patients undergoing surgery with an intermediate-to-high cardiac risk [2]. Most studies comparing epidural analgesia with systemic analgesia report a statistically significant difference in favor of epidural analgesia [3]. However, some studies show a failure rate of 13-47% for epidural catheters [3]. Sometimes epidural catheters are difficult to place, they dislodge and stop working after a day or two, or only a partial or patchy block is obtained with the epidural catheter infusion. In addition, there may be contraindications to placement or maintenance of an epidural catheter due to patient issues such as anticoagulation, coagulopathy, hypotension and systemic infection. Finally, depending on practice location, an acute pain management service may not be in place to help with proper management of an epidural catheter in the hospital. This has led to other techniques and methods of analgesia being considered as alternatives.

There is very little published data on the analgesic benefit of ultrasound-guided TAP blocks with liposomal bupivacaine compared to thoracic epidural infusion. However, many centers have stopped routine placement of thoracic epidurals and started performing TAP blocks instead. Duration of analgesia after TAP blocks is unpredictable, regardless of the local anesthetic agent used. A common observation in practice is that the analgesia provided by TAP block with longer acting agents will wear off after a day or so, and the patients who remain NPO after major abdominal surgery will then be placed on an IV opioid PCA to help provide adequate analgesia until they can be transitioned to oral analgesics. This increases patient opioid use and associated side effects, which can usually be avoided with a working thoracic epidural infusion. In addition, there isn’t any published data available comparing liposomal bupivacaine with the much more inexpensive bupivacaine 0.25% and ropivacaine 0.5% local anesthetic solutions used for TAP blocks.

A study by Ganapathy in 2015 compared continuous bilateral TAP block (ropivacaine 0.5% bolus followed by ropivacaine 0.35 % infusion) with thoracic epidural infusion (0.1% bupivacaine with 10 micrograms/ml hydromorphone) for open abdominal surgery [4]. The study found slightly decreased pain scores in the TAP block group with very similar secondary outcomes at 24 hours after surgery. Although this data is useful, a longer assessment up to 2-3 days post op would have been of greater benefit to help decide which technique might be better.

A study by Wu in 2015 looked at 3 groups: TAP block, thoracic epidural and IV PCA [5]. The results showed decreased opioid consumption in the epidural group compared to both groups, and in TAP block compared to IV PCA. Overall, thoracic epidural was still superior to the other techniques in this study in patients getting open lower abdominal surgery.

We suspect more data on randomized, controlled trials comparing TAP block with bupivacaine liposome injectable solution to thoracic epidural analgesia in open abdominal surgery will be published in the near future. A review of studies on ClincalTrials.gov shows 4 currently registered trials. Until then, all we have is new clinical experience with little solid data.

In conclusion, although the idea of being able to provide prolonged analgesia of up to 72 hours with a one time injection sounds great on the surface, the data and real time experience does not match up with that. In patients lacking contraindications to placement of thoracic epidural, we still prefer epidural to ultrasound-guided TAP blocks. It just provides a more consistent analgesia and achieves that goal without the side effects of opioids.

Jaime Ortiz, MD

References

[1] Rodgers A, Walker N, Schug S, McKee A, Kehlet H, van ZA, Sage D, Futter M, Saville G, Clark T, MacMahon S. Reduction of postoperative mortality and morbidity with epidural or spinal
anaesthesia: results from overview of randomised trials. BMJ 2000; 321: 1493.

[2] Guay J, Choi PT, Suresh S, Albert N, Kopp S, Pace NL. Neuraxial anesthesia for the prevention of postoperative mortality and major morbidity: an overview of Cochrane systematic reviews.
Anesth Analg 2014; 119: 716–25.

[3]Kooij FO, Schlack WS, Preckel B, Hollmann MW. Does regional anesthesia for major surgery improve outcome? Focus on epidural analgesia. Anesth Analg 2014; 119: 740–4.

[4] Ganapathy S, Sondekoppam RV, Terlecki M, Brookes J, Das Adhikary S, Subramanian L. Comparison of efficacy and safety of lateral-to-medial continuous transversus abdominis plane block with thoracic epidural analgesia in patients undergoing abdominal surgery: A randomised, open-label feasibility study. Eur J Anaesthesiol. 2015 Nov; 32: 797-804.

[5] Wu Y1, Liu F, Tang H, Wang Q, Chen L, Wu H, Zhang X, Miao J, Zhu M, Hu C, Goldsworthy M, You J, Xu X. The analgesic efficacy of subcostal transversus abdominis plane block compared with thoracic epidural analgesia and intravenous opioid analgesia after radical gastrectomy. Anesth Analg 2013 Aug; 117: 507-13.

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