Synbiotics in Surgery for Chronic Pancreatitis - A Hobson's Choice?
We would like to thank the authors for their insightful comments. We are indeed pleased that our article has been appraised in detail with constructive criticism. In response to the queries raised, we have answered them in the same sequence as presented by the authors.
Although preoperative demographics and matching controls with cases are key aspects in an unbiased trial, an area that we have taken utmost care to fulfil; we have certain in-house idiosyncrasies and case selection protocols in selecting patients for Frey's procedure that helped us avoid bias (absence of pancreatic endoscopic expertise, etc). With regard to comorbid illness and preoperative antibiotics use, the authors seem to have failed to peruse our previous publication on the research protocol, wherein we have highlighted the very same points that they have attempted to do.1 A composite of the preoperative variables (American Society of Anaesthesiologists Physical Status Classification System [ASA]) has been used to compare the cases and the controls demographically.
Unlike bile cultures, there is considerable variation in the correlation between pancreatic fluid cultures and postoperative infectious complications. The significance of bacteria in pancreatic fluid especially in patients with chronic pancreatitis is not known.2,3 Although we accept that it might be an interesting aspect to look at, it could actually just be an attempt at rediscovering the wheel. In our study, we did not do pancreatic fluid cultures.1
As very eruditely pointed out, a double-blind study would have lain to rest one of the drawbacks of the trial. Unfortunately, due to logistical reasons, the surgeons involved in the study could not be blinded. Regarding the antibiotic protocol, we followed the international antibiotics guidelines, which we have described in our previous publication on the study protocol and did not deem it necessary to repeat ourselves in the present publication.1
We agree with the authors. It did come as a shock to us as well, when we looked at our own infection rates after pancreatic surgery, especially Frey's procedure. Although it is assumed to be a clean case with lower infectious complications than a pancreaticoduodenectomy, data on Frey's procedure had another story to tell. Contrary to what the authors suggest, literature in this regard supports what we did not suspect (higher infectious complications). The infectious complications after pancreatic resections are indeed much higher than what would be intuitively expected. Chaudhary et al4 specifically looked at complications after Frey's procedure; their series had infectious complications accounting for most of their morbidity (16/41 cases—39%). Another aspect that gets overlooked is the infections in “nonsurgical sites” (respiratory/urinary tract, etc). In our series, when only “surgical infections” were taken into consideration, the infectious complication rates fell to 25%, which as mentioned earlier is well within the unsubstantiated low figures quoted by the authors. Undeniably, these nonsurgical site infections also contribute to morbidity and cannot be negated from the equation, especially when there is data to suggest that synbiotics help reduce their incidence. The sample size calculation was based on our own retrospective data analysis over the previous 5 years1,5; these abysmal figures were one of the stimuli for this study. There is also the aspect of infectious complications rates that are region specific, this is something that is irrefutable; intuitive but underreported.5
Undeniably, no article on pancreatic surgery would be complete without a mention about postoperative pancreatic fistula (POPF). As is already known, the rates of clinically significant pancreatic fistula are extremely low, if not negligible after surgery for chronic pancreatitis (firm-hard pancreas, reduced secretions, isolated loop), especially in large volume centers.