As the population of the United States and other Western countries ages, treatment of diverticular disease is projected to impose a larger stress on the health care system, fostering the need for optimal management modalities. Between the years of 1998 and 2005 there was a 38% increase in the rates of elective surgeries for diverticulitis.4
With emerging literature suggesting decreased length of stay and lower postoperative morbidity in regards to elective laparoscopic colon surgery, we hypothesized that laparoscopic treatment of diverticular disease would offer patients similar reductions in complications and overall length of hospital stay. We found that patients undergoing elective laparoscopic surgery for their diverticular disease had significantly lower overall postoperative complications including septic shock, sepsis, deep incisional surgical site infections, and superficial surgical site infections when compared with patients undergoing open surgeries. Previous small series and randomized controlled trials have published similar findings. This report is from a large, multi-institutional database showing that laparoscopy leads to fewer complications after elective surgery for diverticular disease. Moreover, this report further strengthens the evidence favoring the laparoscopic approach to colon surgery, without specific contraindications.
Although elective laparoscopic colon surgery recently has been lauded,9
the recommendation of laparoscopic surgery specifically for diverticulitis has yet to meet similar acclaim. The reasons for the hesitancy to adopt laparoscopic colon surgery specifically for diverticulitis have been reported previously; sigmoid diverticulitis and its complications often cause dense pericolic and mesenteric inflammation and adhesions, distorting anatomic planes, making surgical dissection difficult and potentially hazardous.12
In addition to extensive mesocolic and para-colic dissection and large-vessel ligation, there remains the removal of diseased colon and apprehension regarding anastomosis performance.6
Earlier experiences with open surgery found that elective resection for diverticulitis carried a higher morbidity than similar resections performed for neoplastic disease,13
and early laparoscopic experiences found higher conversion rates compared with the same resections for other indications.14–16
However, later experiences found that laparoscopic colon resection for diverticular disease was feasible and safe17,18
and most more recent studies cited conversion rates between 20%6
which is not dissimilar for current large series reports of conversion rates for neoplastic disease.19
The aforementioned series included cases of complicated diverticulitis and found that increased conversion was related to the presence of a fistula or abscess requiring preoperative drainage. These results were corroborated by Sher et al,20
who also found higher conversion rates in those patients with more advanced class of disease classification as per Hinchey et al.21
However, regardless of reasons for reluctance or uncertainty, the results of this multicenter database would suggest that laparoscopy decreases overall complications and provides support for its universal acceptance as the procedure of choice for diverticular disease warranting surgical intervention.
Longer operating room times and thus increased surgical costs have been another reason for the lack of adoption of laparoscopic colon resection. Indeed, earlier studies by Pfeifer et al22
and Saba et al23
found significant increases in cost associated with laparoscopic colon resection. However, recent data challenge this finding. Studies looking at cost analysis at institutions with considerable laparoscopic experience have reported decreased costs when taking into account length of stay, which would be a function of efficient surgical teams, limiting complications and conversion rates.24,25
Our results corroborate these outcomes, showing that although surgical times are slightly longer, this is offset by the significant reduction in postoperative length of stay. Also, the difference in surgical times is on the order of minutes, and as laparoscopic experience increases among surgeons, surgical time likely will continue to decrease.26
Our results also identify multiple preoperative/intraoperative variables that, on multivariate analysis, portend an increased risk of overall complications. Although many of these variables may be expected, some are not as explicit, such as a history of severe chronic obstructive pulmonary disease. Some of these variables are addressed when comparing open and laparoscopic surgery, including blood transfusions. Thus, the benefits of laparoscopic surgery with regards to complication rates appear to befit many of the preoperative and intraoperative variables that alone are risk factors for complications.
We acknowledge the limitations of this study. First, the patients included in this dataset were identified from the American College of Surgeons NSQIP database, which is an amalgamation of patients from 199 voluntary institutions. These institutions are disproportionately large academic hospitals with high-volume colon and rectal surgery centers. Unfortunately, we cannot correct for differences in hospital variables (procedure volume, number of beds, specialized centers), or differences in operating surgeon (procedure volume, fellowship training). The data are gathered prospectively and we believe reflects a more accurate description of real-world practices than that of a randomized controlled trial. In addition, only 30-day outcomes can be measured, which relies on nurse data extractors and phone call follow-up evaluation. These nurse extractors are hospital specific and often are unable to follow up with patients who are admitted to other hospitals to pursue future care.
Another significant limitation exists in the nonrandom assignment of patients to the type of surgical approach. Although we attempted to control for preoperative and intraoperative factors that may have affected our results, there most certainly are disease states and variables, as well as clinical judgment of the operating surgeon for which we cannot devise an acceptable control. Furthermore, we have tried to eliminate those patients who underwent an emergency surgery. However, this includes only those patients who undergo surgery within 12 hours of admission. Given the high rate of dirty/infected wounds in the study () we assume that some patients failed attempted medical management and required surgery in a less than ideal situation. We have attempted to control for these differences using multiple statistical methods including propensity score adjustment () and stratification according to variables known to increase complications (). Despite the obvious differences between the 2 groups, laparoscopy was found to decrease the rate of postoperative complications independently.
The fact that we cannot accurately determine the rate of conversion of a laparoscopic procedure to an open surgery also introduces a concerning limitation. Unfortunately, no CPT code exists for conversion from a laparoscopic to an open surgery. In this article we have included in the laparoscopic group all patients coded as having undergone a laparoscopic surgery regardless of secondary and tertiary CPT codes. Likewise, all patients coded as having undergone an open surgery were included in the open group regardless of the secondary and tertiary codes. Although we could attempt to estimate conversion based on these secondary and tertiary fields, there is no way to fully know the intent of the operating surgeon. For example, the surgeon involved in a procedure coded as an open surgery with a laparoscopic code in the secondary field may have had the intent of performing only a diagnostic laparoscopy. Including such a case as a conversion would not be valid. Likewise, a procedure coded as a laparoscopic surgery with a laparotomy in the secondary field might be included as a conversion. However, it would not be possible to know why the surgery was converted or know the intent of the laparotomy. Therefore, we have chosen to analyze the data only using the primary CPT codes because we believe it is the most accurate analysis introducing the least amount of bias on our part. Clearly, this choice could affect our data both negatively and positively. Conversion to open colectomy has been reported to carry a higher morbidity, longer hospital stay, and higher cost in some series.27,28
However, other series have not found higher complication rates for patients requiring conversion and have postulated that increased experience with laparoscopic colon resection would reduce the overall numbers of conversion.12
This has been confirmed in multiple other series that have found that the learning curve associated with decreased conversion rates varied between 11 and 70 cases per surgeon.26,29–33
Therefore, as skill and comfort with the laparoscopic technique improves, conversion rates may continue to decrease, resulting in lower rates of postoperative complications.34
However, we recognize from practices such as ours and those of our colleagues that as skill with the technique increases, the willingness to apply the technology broadly increases. Anecdotally, this results in a conversion rate that is relatively stable over time. How the broad application of laparoscopy to the surgical treatment of diverticulitis affects the overall rate of postoperative complications remains to be seen.