Laparoscopic Management of Small Bowel Obstruction in Children

Introduction

Mechanical bowel obstruction is a commonly encountered surgical problem in both the adult and pediatric population.^1,2 In children, acute small bowel obstruction (SBO) is a common cause of hospital admission and can require emergent or urgent operative intervention. ³ Although there are multiple etiologies of SBO in children, the most frequent cause is postoperative adhesions. To quantify this problem, postoperative adhesions complicate >15% of open abdominal surgeries in the Western world, with an overall incidence in the pediatric population ranging from 5% to 12%.^4–7

Operative intervention is required for patients with complete bowel obstruction, concerns for intestinal ischemia, or failed medical management. Historically, the operative management for patients with SBO has been open adhesiolysis. Despite being an independent risk factor for subsequent bowel obstruction, this approach continues to be widely utilized today. ¹

Although there has continued to be expansion in the use of laparoscopy in most areas of general surgery, its use in the management of SBO has failed to gain widespread favor.^8,9 However, laparoscopy has the theoretical advantage of minimizing additional adhesion formation, potentially decreasing SBO recurrence. Laparoscopic surgery has also been reported to be associated with faster recovery of bowel function, reductions in postoperative pain, length of hospital stay (LOS), wound infections, and incisional hernias.^9,10

Data citing the success and benefits of pediatric patients with SBO managed laparoscopically have been limited. For this reason, we conducted a retrospective, single-institution review of patients with an SBO managed via a laparoscopic approach as their initial operative intervention.

Methods

A retrospective chart review was performed after approval from the Institutional Review Board. The study included all patients found to have an SBO who underwent management via a laparoscopic approach between January 2001 and December 2008.

Data collected included demographics, type of operation, preoperative radiographic evaluation, and intraoperative findings, including etiology of bowel obstruction. The need and reason for conversion to an open approach were also noted. Time from the original operation as well as the type and number of operations before SBO were recorded. Length of gastric decompression, total LOS, time to flatus or bowel movement, need for total parenteral nutrition, length of follow-up, recurrence, and time to recurrence were also collected.

Data are presented as mean ± standard deviation. Comparisons were made using a two-tailed Student's t-test for continuous variables and Chi-squared for discrete variables, with Yates correction where appropriate. Significance was defined as a P < 0.05.

Results

Discussion

Laparotomy will lead to the formation of adhesions in nearly 95% of patients. ¹¹ Adhesions, almost exclusively secondary to previous laparotomy, are the dominant etiology of SBO. The current hypothesis is that adhesions occur due to manipulation of the of serosal surfaces that disrupts the mesothelium, leading to a local inflammatory response that leads to an influx of fibroblasts that deposit fibrin creating fibrous adhesions. ¹² Other less common causes of obstruction include volvulus, intussuseption, incarcerated hernias, and malignancy.

The first reported case of laparoscopic adhesiolysis for SBO was published in 1991. ¹³ Since that report, the feasibility of the laparoscopic approach for the operative management of SBO in selected patients has been the topic of a hand-full of published studies in the adult literature, with far fewer reports in the pediatric population.^14,15 Despite its many potential benefits, there has been reluctance in utilizing the laparoscopic approach for SBO. This reluctance may be based on the technical difficulty of a laparoscopic adhesiolysis and the perceived increased risk of iatrogenic injury to the distended, thin-walled, adhesed bowel. Laparoscopy can offer advantages over conventional laparotomy for SBO. It is reported to be associated with fewer postoperative adhesions. ¹⁶ Specifically, in a study conducted by the Operative Laparoscopy Study Group, 12% de novo adhesions were found by laparoscopic procedures versus 51% after open operations. ¹⁷ Laparoscopic surgery is also associated with faster recovery of bowel function, reductions in postoperative pain, LOS, and wound infections. The incidence of port-site herniation from laparoscopic procedures is 0.02%–2.4% versus the 11%–20% reported incidence of incisional hernias after laparotomy. ¹⁸

Our conversion rate to laparotomy was 32.4%, which is within the published rates in the adult literature of 6.7%–52%. ¹⁴ A recent systematic literature review of laparoscopic management of SBO in adults demonstrated a 66% success rate with laparoscopic intervention for SBO. ¹⁴

Several important data points from the current study bear further discussion and have clinical and technical implications. First, the most consistent factor associated with conversion to laparotomy in our series was the presence of intestinal volvulus, with all 3 cases encountered requiring open adhesiolysis and reduction of volvulus. Thus, in the presence of intestinal volvulus, consideration for conversion should occur quickly. Second, the most common reason for conversion was inadequate working space secondary to significantly dilated bowel loops. Additionally, 18% of our study population was converted to an open approach after laparoscopy failed to identify an etiology for the SBO.

Not surprisingly, the most common etiology of SBO was intra-abdominal adhesions, and nearly 75% of these patients were managed successfully via laparoscopy. Of note, no association between the number of previous operations and the subsequent conversion to laparotomy was identified. This is consistent with previously published series that fail to show any correlation between the number of previous abdominal operations and the rate of conversion. ³

Five (14.7%) patients developed postoperative complications, and none of required re-operation. One patient (2.9%) sustained an iatrogenic enterotomy that was recognized intraoperatively and repaired after conversion to laparotomy. The enterotomy rate of 2.9% lies within the range reported in the adult literature of 3%–17%.^3,14,19 In this setting, laparoscopic repair of the enterotomy can be considered. However, conversion to a laparoscopic assisted or conventional laparotomy should be performed based on the extent of the injury, the condition of the abdominal cavity, and the experience of the surgeon. The lower incidence of enterotomy in our patients is likely related to observance of key technical principles, such as the open technique for the insertion of the umbilical port, direct observation of the insertion of all ports, conservative use of electrocautery, and the use of atraumatic for bowel manipulation. In this study there was a single mortality (2.9%) involving a patient who developed sepsis related to ischemic bowel within 30 days of their operation. The morbidity and mortality observed in this study lie within the published incidence of pooled studies from a systematic review of the adult literature of 1.5% and 15.5%. ¹³

We identified a 14.7% recurrent SBO rate in the laparoscopic adhesiolysis group in this study. Although there were no cases of recurrence in the group that was converted to open, there was no statistically significant difference in terms of recurrence between the 2 groups. This could be attributed to both a small sample size as well as to a relatively short follow-up period of 7.3 ± 14.8 months for the entire study population. This is a concerning trend that will require further follow-up. This difference in recurrence may be related to a more limited adhesiolysis performed during laparoscopic adhesiolysis than what is normally performed during the open approach. A more limited adhesiolysis could potentially contribute to cases of early recurrence of the SBO. In our series, 2 patients developed a recurrent SBO within 6 weeks of their initial laparoscopic adhesiolysis. Both patients underwent an open approach for their recurrence. To date, there are no published studies that demonstrate a higher recurrence rate for the laparoscopic approach. No conclusion can be made regarding the true long-term recurrence rate since this study, along with all other published studies, is plagued by their retrospective nature, a short follow-up period, and small sample size.

Comparing the published reports of return of bowel function reveals a more rapid return after laparoscopic adhesiolysis when compared with patients who require conversion to open, 1.5–2.6 days versus 5–6.6 days.^13,20,21 In this study, the mean time of return of bowel function was similar with the laparoscopic group, and it was 2.8 ± 1.8 days compared with 5.7 ± 5.6 days in the converted group. This was statistically significant and supports previously published reports that demonstrate a faster return of bowel function after most laparoscopic procedures. However, the groups are likely biased by severity of adhesions and/or obstruction, with the laparoscopic group being less severe than the converted group, thus one of the reasons that the laparoscopic approach was successful. The mean LOS for patients with SBO managed laparoscopically reported in the literature ranges from 3.7 to 7 days versus 6.7 days to 16.6 days in the converted group.^13,20,21 The LOS in our laparoscopic group was 6.2 ± 2.6 days, whereas in the converted group it was 12 ± 10 days, which was statistically different. However, LOS is primarily dependent on return of bowel function; therefore, the shorter LOS is also likely a reflection of patient selection bias compared with actual technique.

Although there is a 65%–70% success rate for the laparoscopic management of SBO in most published reports, as well as in our current study, it is imperative that a low threshold for conversion to laparotomy or to a laparoscopically directed mini-laparotomy exists. In the face of limited visibility, ischemic bowel, intestinal volvulus, enterotomy, or the inability to complete the procedure in a timely fashion secondary to other intraabdominal pathology, conversion to laparotomy should be forefront in the minds of every surgeon performing laparoscopic operations, emphasizing the logic that sound surgical judgment should not be misconstrued as a sign of failure.

In conclusion, the primary appeal of laparoscopy in the initial management of SBO is the potential to minimize the peri-operative morbidity associated with laparotomy. When it is not feasible to complete an adhesiolysis laparoscopically, the laparoscopic approach can still be useful for the diagnosis of ischemic bowel and/or volvulus. It also can allow for takedown of the abdominal wall adhesions and identification of the point of obstruction at which time a focused, rather than major, laparotomy can be used.

This study has demonstrated that laparoscopy for the management of SBO in children is safe and can be therapeutic in >65% of cases in selected patients. We recommend initial exploration in children with SBO be carried out via the laparoscopic approach, with an understanding that conversion to an open approach, which should not be viewed as a failure, may be necessary to complete the operation.