Response to the Comment on “LekCheck: A Prospective Study to Identify Perioperative Modifiable Risk Factors for Anastomotic Leakage in Colorectal Surgery”

Reply: We would like to thank Dr. Qu-Xia Zhang and Dr. Bin-Bin Xu for their great interest in our work and we are honored by their effort to comment on our article, that has prospectively identified potentially modifiable risk factors for colorectal anastomotic leakage (CAL).1 Please find our response to their concerns below. To begin with, colleagues Zhang and Xu questioned whether the LekCheck-checklist could have been interpreted differently by individual physicians. It is true that a few items are subjective measurements (eg, the assessment of contamination of the operative field), however most items included in the LekCheck, derived from a previous review conducted by our study group and approved by members of the Dutch Taskforce Colorectal Anastomotic Leakage, are either dichotomies or objective measures.2 Values of LekCheck items were comparable between 14 international academic and non-academic hospitals that participated in the study. It is our believe that the group effort of completing this checklist leads to another important improvement: intensified intraoperative interaction and collaboration between surgeons and anesthesiologists. The second issue addressed by the authors is the association of hemoglobin (Hb) and CAL, specifically the cut-off values chosen for Hb. Although reported cut-off values were chosen based on previous research,2 we agree that Hb, representing the single most important risk factor for leakage, requires further exploration. Therefore, an additional analysis using smaller intervals was conducted. The results as demonstrated in Table 1 indicate that almost a third of the patients with an Hb level of less than 11.0 g/dL developed CAL. Hence, surgeons face the question of whether or not a patient should be operated with an Hb of less than 11.0 g/dL. In addition, we believe that an Hb of at least ≥12.0 g/L for both sexes is advised for the prevention of CAL. In line with this, a consensus statement developed by experienced clinicians and researchers recommended preoperative optimization that should target an Hb concentration of ≥13.0 g/L (8.0 mmol/L) for both sexes.3 With regard to blood management, the use of preoperative or postoperative blood transfusion was not captured in the current study protocol. A study that investigates the effect of optimizing perioperative blood management and other modifiable factors is currently undertaken. TABLE 1 - Distribution of Hemoglobin Levels and Risk of Colorectal Anastomotic Leakage (n = 1.458) Univariate Analysis Hemoglobin N % of CAL (n = 124) OR (95% CI) P value <10.0 g/dL 85 27% 7.84 (4.37–14.06) <0.001 10.0–10.9 g/dL 107 26% 7.49 (4.34–12.93) <0.001 11.0–11.9 g/dL 180 12% 2.94 (1.67–5.14) <0.001 12.0 – 12.9 g/dL 289 5% 1.16 (0.62–2.15) 0.643 ≥13.0 g/dL 797 5% 1.00 (ref) — CAL indicates colorectal anastomotic leakage; CI, confidence interval; OR, odds ratio. Colleagues Zhang and Xu also commented on the application of epidural analgesia, especially in patients undergoing procedures with distal anastomoses. Epidural analgesia is strongly advised in the Enhanced Recovery After Surgery (ERAS) guideline for open colorectal surgery to achieve acceptable pain levels and avoid or reduce the use of high dose opioids. Nevertheless, as the writers correctly pointed out, there is much debate about the effect of epidural analgesia on CAL. The fact that epidural analgesia was not an independent risk factor for CAL in our studied patients with a colo-rectal/ileo-rectal anastomosis, may likely represent a type II error given the limited sample size and small number of events in this subgroup (ie, CAL rate of 41 out of 348 patients). As the determination of the type of analgesia is performed based on more predicted outcome measures than just CAL (eg, pain, gastrointestinal dysfunction), the individual patient undergoing open colorectal surgery might still be a good candidate for epidural analgesia.4 Further prospective research on the use of epidural analgesia and its associated factors (eg, hypotension, vasopressor use) regarding CAL are needed and has already been initiated by our group. In our opinion, CAL is the result of several interrelated perioperative factors, some of which are fixed and some of them are potentially modifiable. The LekCheck can be used as a tool to identify these modifiable risk factors during surgery and challenges both the surgeon and the anesthesiologist to optimize intraoperative conditions in order to prevent this dreaded complication.