The results of this study confirm that SBO remains one of the more common postoperative complications associated with restorative proctocolectomy. The overall incidence at 1 y of 14% in the open and 16% in the laparoscopic groups remains high and is a significant burden worthy of discussion with patients undergoing this procedure. Despite the presumed advantage that a laparoscopic approach may decrease the inflammatory response and theoretically lead to less adhesion formation, we noted no statistically significant differences between the timing and severity of SBO between the open and laparoscopic groups. This may be due to the fact that in almost all of these laparoscopic cases, the pelvic portion of the procedure (proctectomy and IPAA) is still performed via
a small suprapubic incision and thereby still inciting the usual inflammatory response. However, after breaking down our population into early and late presentations, as well as pre- and post-ileostomy reversal, there was a slight trend toward the majority of laparoscopic-related SBOs presenting in the pre-takedown period. Though the reason for this is unclear, it would seem that in this early period adhesion formation is less likely to be responsible for bowel obstruction and other causes are accountable (i.e., mechanical). Few other groups have similarly compared the incidence of SBO between laparoscopic and open approaches. However, one such group from the Cleveland Clinic revealed similar findings to the current study [7
]. They noted a similar incidence of SBO between open and laparoscopic approaches at 30 d (open, 4% and laparoscopic, 6%), 1 y (open, 13% and laparoscopic, 20%), and 5 y (open, 16% and laparoscopic, 21%) (P
= NS) [7
Although not the impetus of this study, comparisons of the laparoscopic and open groups again confirmed one of the benefits of the laparoscopic approach, namely, that the length of hospital stay is shortened. We and others have previously demonstrated this advantage of a laparoscopic over open approach for restorative proctocolectomy, though operative times are consistently longer [9
]. In addition, since laparoscopy has also been shown to have a beneficial effect on adhesion formation [14
], it would seem that by utilizing this approach for restorative proctocolectomy, a decrease in the incidence of SBO might be seen. However, this was not apparent in the current study. Despite these findings, we also noted that the time period from original surgery to ileostomy reversal was decreased in the laparoscopic group. Though this may be partially explained by a few instances where early required reoperation in this group resulted in earlier reversal, this finding likely represents the assumption of less adhesion formation after laparoscopy and, therefore, an offering of earlier ileostomy reversal.
In our review, we noted that adhesions were causative in cases of SBO requiring operative intervention in 74% of the open cases compared with only 33% laparoscopic. While this finding was not found statistically significant, it does parallel prior research, noting again that laparoscopy is associated with a reduction in adhesion formation [14
]. With this in mind, it might confirm that in the laparoscopic pre-ileostomy takedown period, the small bowel remains freely mobile as a result of fewer adhesions and is potentially more prone to mechanical kinking or twisting, especially at the ileostomy site. Unfortunately, we have been unable to identify any technical factors that may be responsible for these findings and it does not appear that ileostomy orientation plays a role. This contrasts with the open group, which demonstrates a more evenly distributed time course for SBO and more SBOs caused by adhesions. It, therefore, seems possible that over a longer time period, the laparoscopic group might reveal a lower incidence of SBO, since adhesions during that time would likely be responsible. While the incidence of SBO did increase over the course of patient follow-up in the open compared with the laparoscopic group, no significant differences were noted and, due to the short term follow-up in this study (especially in the laparoscopic group), this trend cannot be confirmed at present. Longer term evaluation is necessary to investigate this possibility further.
Although this is a large series of both open and laparoscopic cases, we recognize the limitations of a retrospective review and it may therefore be difficult to make reliable conclusions with the number of predictor variables examined. In addition, we recognize the possibility of losing some patients to follow-up, as they could potentially seek care for a SBO elsewhere. Examination of the demographic data does reveal some differences between the laparoscopic and open groups. We noted that the laparoscopic group demonstrated an increased female population, lower BMIs, lower ASA scores, and, as expected, significantly fewer patients with prior colectomy or any other prior abdominal surgery. These differences are likely attributed to careful patient selection in the laparoscopic group, especially in the earlier period of utilizing this approach. However, even when these findings are corrected for with logistic regression, laparoscopic patients failed to demonstrate significant differences in the incidence or severity of SBO.
The similar incidence of SBO between the laparoscopic and open groups led to an evaluation of multiple factors in an attempt to identify those contributing to an increased risk. Of these factors, only CAD, prior appendectomy, and pouch configuration were associated with an increased risk of SBO, though prior appendectomy was not significant when adjusting in a multivariate model. In our study, use of the S pouch configuration was by far the most common and demonstrated the lowest associated incidence of SBO, while the W and J pouches revealed an increased SBO risk. Since our study group was made up of only a small number of W and J pouch configurations, further study is necessary to determine if this finding holds true. Aside from this, evaluation also revealed that CAD was associated with an increased risk of SBO. A link between CAD and SBO seems unlikely and is difficult to explain, though again a small sample size may be responsible. Although it is possible that prior appendectomy (from the univariate analysis) could contribute an increased risk for the development of SBO, an evaluation of other prior abdominal surgeries failed to reveal similar results. In addition, we have shown that even in cases where a three-staged procedure with prior colectomy was utilized, there was no increase in the incidence of SBO. Finally, we also identified cases from the operative record, utilizing an adhesion prevention barrier. However, we found that no beneficial effect with respect to SBO was demonstrated. This is similar to an earlier prospective trial failing to show prevention in the rate of SBO with use of Seprafilm (Genzyme) [16
In summary, the burden of postoperative small bowel obstruction after restorative proctocolectomy is not changed with a laparoscopic approach. Most cases tend to occur in the early postoperative period, especially prior to ileostomy reversal.