To the Editor,

We read with great interest the article of Kulasegaranet al. [1] in a recent issue of the journal. The authors evaluated one hundred patients undergoing laparoscopic total pre-peritoneal hernia repair and concluded that pre-peritoneal local anaesthetic instillation does not offer any advantage in pain scores at 4 and 24 h after surgery. The authors should be congratulated for performing a well-designed study in an important topic (e.g. acute pain) in patients undergoing hernia repair [2, 3]. Moreover, local anesthetic instillation has become the current emphasis on many studies evaluating acute pain [4, 5].

Although the study of Kulasegaran et al. was well conducted, there are some concerns regarding the trial that needs to be clarified to determine the validity of the results. First, it is not clear if intraoperative analgesic administration was standardized using a specific criterion as this can alter the primary outcome [6]. Secondly, as fentanyl was used to treat postoperative pain, it is expected that patients were treated to keep low postoperative pain. One could argue that this is the reason for the lack of analgesic benefit demonstrated by the study. Lastly, the authors performed a pre-surgical versus post-surgical analysis in Table 2. It would be important to demonstrate a simple pain analysis by study groups since the P value for the pre- and post-analyses was almost statistically significant (P = 0.06).

We would welcome some comments to address the aforementioned issues. This would help to further substantiate the findings of this important study.