Thank you for the opportunity to respond to the informative letter by Dr O’Neill, Dr Lordan and Dr Quiney. At our institution, concerning patients undergoing major hepatic resections, we are concerned about the safety of epidural anaesthesia because of the risk of postoperative coagulopathy and the potential for bleeding complications and devastating sequelae of epidural haematoma and spinal cord compression.
In patients undergoing liver resection, we have demonstrated a strong correlation between hepatic resection sizes, duration of surgery, and prolongation of the prothrombin times in the postoperative period . A direct relationship between prolongation of the prothrombin times and the extent of the liver resection has also been confirmed in other studies [2, 3]. Disorders of coagulation can still occur even after uncomplicated liver resection in patients who have normal pre-operative coagulation profiles, even in the absence of massive transfusion [2, 4, 5]. This finding has major implications for anaesthetic practice, particularly when considering the use of an indwelling epidural catheter for intra-operative anaesthesia and postoperative analgesia. As pointed out in the letter by Dr O’Neill and colleagues, continuous epidural anaesthesia and analgesia is an accepted technique for patients undergoing major hepatic resection; however, at our institution, along with others [6, 7] we now consider this technique to be unsafe. We emphasise the importance of the segmental anatomy of the liver. For patients undergoing left hepatectomy (segments 2,4 and 4) or left lateral segmentectomy (segments 2 and 3), in the absence of contraindications, we still favour neuraxial-based techniques for intra-operative and postoperative analgesia. In our experience, these resections are minor, the duration of surgery is invariably shorter and resection weight is smaller. Therefore, the changes in coagulation are less significant in the postoperative period. However, patients undergoing extended right hemihepatectomy (segments 5,6,7 and 8), extended right hemihepatectomy (segments 4,5,6,8 ± 1) or extended left hemihepatectomy (segments 2,3,4 and 6,7 or 5,8) behave differently. In our experience these resections are more prolonged, the resection size is larger, the need for intra-operative blood transfusion is more likely and the risk of postoperative coagulopathy and adverse sequelae is greater .
Balancing the advantages of optimal analgesia against the risks associated with current techniques to achieve the greatest benefit requires a body of clinical trial evidence that does not yet exist. Given the known haemostatic derangements that can occur after major hepatic resection, the question of whether the risks of epidural analgesia are justifiable in the management of pain for patients undergoing hepatic resection needs to be further discussed. Dr O’Neill and colleagues make an excellent argument that alternative analgesic options such as interpleural analgesia may be associated with different safety concerns (and a poorer quality of postoperative analgesia). We acknowledge that levobupivacaine serum levels were not confirmed in our previous study  and for the reasons outlined in their letter, agree that safe confirmation of serum levobupivacaine levels needs to be demonstrated before interpleural analgesic techniques can be routinely recommended, particularly for patients undergoing major hepatic resections. An international liver resection management and peri-operative outcomes database may help define the safety of neuraxial based techniques as well as determine effective multimodal alternatives .