Feasibility of robotic-assisted pancreatic resection in patients with previous minor abdominal surgeries: a single-center experience of the first three years

Today, pancreatic surgery is still associated with a high risk of postoperative complications despite substantial improvements in surgical techniques and the performance of surgery in high-volume centers [1‐3]. Although no generally accepted definition of high-volume centers exists (range > 10 to > 100), it is well accepted that with increasing annual numbers of major pancreas resections the quality improves [4, 5]. At present, notwithstanding developments in pharmacologic and oncologic treatment, surgical resection is still the primary treatment of benign and malignant pancreatic lesions.

In 1909 Walter Kausch established the first steps in pancreaticoduodenectomy. After Kausch died in 1935, Whipple took the first procedure and defined the pancreaticoduodenectomy, called “Kausch-Whipple Operation” and thereby founded modern pancreatic surgery [6, 7]. However, due to high rates of complication, pancreaticoduodenectomy was performed infrequently in the middle of the last century [6]. During the following decades, high volume centers developed, and the mortality rate decreased to five percent [8, 9]. Despite substantial improvements, the rate of postoperative complications, such as postoperative pancreatic fistula (POPF), postoperative pancreatic hemorrhage (PPH), surgical site infections (SSI), insufficiency of the implemented anastomoses, and pulmonary complications, remains a significant issue [1‐3].

In the last decade, minimally invasive techniques have revolutionized modern surgery in general by reducing postoperative morbidity and mortality [10]. Several studies demonstrated the known benefits of minimally invasive surgery with comparable rates of perioperative mortality and morbidity [5, 11, 12]. The benefits of a minimally invasive approach are based on reduced trauma to the abdominal wall reducing blood loss, postoperative pain, and surgical site infections (SSI), leading to better and faster postoperative recovery [10, 13, 14]. Consecutively, in the early 90 s, the first laparoscopic partial pancreaticoduodenectomy (LPD) was performed [15]. In the following, laparoscopy has also been introduced to the partial pancreaticoduodenectomy. Due to several limitations, laparoscopy is currently mostly limited to distal resections [10, 16]. After its implementation, robotic assistance compensated for several disadvantages of laparoscopy: It provides a three-dimensional view and more sophisticated instrument manipulations, reduces tremor transmission, and allows for up to seven degrees of freedom. Therefore, more complex oncological operations became safe and feasible [17, 18]. A recent meta-analysis comparing robotic-assisted resection with laparoscopic resection showed that the use of robotic assistance leads to fewer blood transfusions, lower conversion rates, shorter procedure times, and lower total costs, thereby confirming its superiority in complex oncologic surgery [19]. Nevertheless, adhesions after previous abdominal surgeries may hinder the success and practicability of robotic-assisted pancreatic resection. Abdominal adhesions are well known to prolong surgery time, and adhesiolysis is associated with iatrogenic bowel injury [20]. The goal of the following analysis was to investigate the impact of prior abdominal surgeries on perioperative complications and conversion rates in robotic-assisted pancreatic surgery.

Prior abdominal surgery is a commonly mentioned factor to prefer open procedure rather than the laparoscopic approach in the past. We demonstrate that robot-assisted pancreas resection can be performed safely even after previous abdominal surgery. Neither intraoperative required conversion nor time of surgery was affected by a positive history of abdominal surgery. To the best of our knowledge, there has been no other systematic study focusing on the correlation of prior abdominal surgery and the robot-assisted approach to pancreatic surgery.

Over the past three decades, minimally invasive surgical procedures have gained wide acceptance among patients and surgeons because of their safety and improved surgical outcomes. From the starting point of the first laparoscopic surgeries as early as 1910, it took almost a century and countless developing steps (technically and medically) to the latest robotic-assisted Whipple procedure [27]. This revolution is carried by numerous published studies demonstrating the superiority of the laparoscopic approach in general, emphasizing less blood loss and rapid recovery [28‐31]. On the other side, no randomized controlled trial (RCT) has yet been published on robot-assisted surgery versus open surgery in the field of pancreas resection [32].

However, in the decision-making process of open versus minimal invasive resection, previous abdominal procedures are often seen as contraindications due to suspected abdominal adhesions. However, our study showed no significant differences between the groups regarding severity of complications, intensive care unit or in-hospital stay, or any other relevant outcome parameter. Subgroup analysis did not reveal any specific group of previous surgeries (open/multiple/upper abdomen) with a higher risk for complications. It must be mentioned that within this group, the extent of previous surgeries was limited to appendectomies, cholecystectomies, or gynecological surgeries. For this reason, this current study may not directly be relatable to recent reports of increased time of surgery after previous major liver resections. A recently published study of liver resections showed that previous liver surgery, which may be considered major surgery, was associated with a significantly longer time of surgery but still had a similar complication rate [17].

Looking at specific complications related to pancreatic resection, we could demonstrate that DGE, POPF, and PPH were comparable in patients with or without previous abdominal surgeries. This is in line with recent studies on open versus laparoscopic surgery, which have shown that laparoscopic pancreaticoduodenectomy has identical risk and, in some cases, a lower risk of developing POPF than open surgery [33, 34].

However, according to recently published multinational registries, the minimally invasive pancreas resection rate is still far below 15% [35]. Hence, some hurdles prevent its wide application. On the one hand, the reason for that may be that pancreatic surgery still ranks among the most complex abdominal procedures with high morbidity and mortality [16]. Therefore, more than in other surgical fields, it is necessary to have centers of excellence with sufficient amounts of resections per year. Just with an adequate caseload, the development of minimal invasive skills and training of fellows becomes possible [5, 36, 37].

Another reason for the low numbers of minimally invasive procedures in pancreatic resection is undoubtedly due to a selection bias. However, as known from other laparoscopic procedures, it is especially the old, multimorbid patients that profit the most from reduced trauma to the abdominal wall [38]. Patients with prior abdominal surgeries might be perceived as too complex for similar reasons. Despite a history of previous abdominal surgery, the applicability of a pneumoperitoneum during the performed surgery, e.g., due to cardiovascular comorbidities, might serve as an explanation.

Our study has several limitations. First, although the presented study is a prospective observational study, it has an inherent selection bias. As robotic-assisted surgeries and not consecutive cases define the cohort, open pancreas resections are missing. Accordingly, it is not reasonably possible to assess the reasons for or against a minimally invasive approach per patient retrospectively. Secondly, due to cohort size, the power of subgroup analysis might be too low. Hence, specific surgical histories, especially major surgeries (e.g., liver transplantation and gastrectomy), have not been in our cohort and, of course, might affect the postoperative outcome after robotic-assisted pancreas resection.

In conclusion, our study indicates that a history of minor abdominal surgery is not associated with longer operative time or postoperative complications, including pancreatic fistula or hemorrhage in robotic pancreatic surgery. Therefore, we suggest that robotic-assisted surgery should be considered in all patients undergoing pancreatic surgery regardless of previous surgery. Furthermore, in upcoming RCTs about the relevance of robotic assistance in pancreatic surgery, special attention should be paid to patients with a history of previous abdominal surgeries.