HHS Public Access Author manuscript Author Manuscript
Am Surg. Author manuscript; available in PMC 2016 January 04. Published in final edited form as: Am Surg. 2014 March ; 80(3): 261–269.
A Comparative Analysis between Laparoscopic and Open Adhesiolysis at a Tertiary Care Center Stephen W. Davies, M.D., M.P.H., Jake R. Gillen, M.D., Christopher A. Guidry, M.D., M.S., Timothy E. Newhook, M.D., Nicolas H. Pope, M.D., Tjasa Hranjec, M.D., M.S., Robert G. Sawyer, M.D., and Peter T. Hallowell, M.D. University of Virginia School of Medicine, Charlottesville, Virginia
Author Manuscript
Abstract
Author Manuscript
Laparotomy has been the favored approach regarding surgical management of small bowel obstruction (SBO); however, laparoscopy may offer improved outcomes. Patients undergoing laparoscopic lysis of adhesions (LOA) at our institution for SBO will have lower postoperative morbidity and 30-day mortality. Patients undergoing LOA at our institution, from 2000 to 2011, were reviewed. Categorical data were analyzed with χ2 or Fisher’s exact tests. Continuous data were analyzed with Student’s t test or Wilcoxon rank sum. One hundred two (38 laparoscopic, 64 open) LOA cases were selected. Perioperative contamination and conservative management were higher in the open group. Open cases had a greater incidence of intensive care unit (ICU) admissions and longer length of stay. Stratified analysis determined a strong association between perioperative contamination and a higher incidence of ICU admission, perioperative contamination and longer LOS, and conservative management and longer LOS. Finally, patient outcome did not differ between those treated by surgeons trained in minimally invasive surgery (MIS) compared with those not trained in MIS. Careful consideration of surgical approach and timing is called for in all patients with SBO; however, whenever possible, laparoscopic preference should be given to most patients in an expeditious fashion irrespective of MIS training.
Author Manuscript
Intestinal obstruction is one of the more frequently encountered disorders of the small bowel and contributes to a large number of annual hospital admissions and subsequent financial expenditures. A study in 2001 identified that, in the United States alone, over $1 billion was spent on bowel obstruction in 1994.1 Intestinal obstruction is most commonly associated with gastrointestinal paralysis (ileus) secondary to bowel inflammation that may be attributable to surgery, medication, or inflammatory bowel disease. A smaller percentage is associated with mechanical compression, either intrinsic or extrinsic.2 Regarding mechanical small bowel obstruction (SBO), 65 per cent of cases, on average, are attributable to intraabdominal adhesions.3 Adhesions have been previously defined as “abnormal fibrous connections that may contain vascular channels, which join surfaces in abnormal locations.”1 Previously, the primary etiology of obstruction was considered to be external
Address correspondence and reprint requests to Stephen W. Davies, M.D., 4008 Cindi Lane, Winterville, NC 28590. [email protected]. Presented as a gold medal podium presentation at the 2013 Southeastern Surgical Congress, Annual Scientific Meeting, Jacksonville, FL, February 9–12, 2013.
Davies et al.
Page 2
Author Manuscript
hernia incarceration with subsequent development of strangulation. However, as abdominopelvic surgery has evolved, so has the development of adhesion-related obstruction, which is now considered to be the primary cause.1 It is estimated that over 300,000 patients are hospitalized and undergo surgery for adhesion-related SBO annually.4 Open adhesiolysis through a midline laparotomy incision is considered to be the standard approach; however, since 1990 when Clotteau described the first laparoscopic adhesiolysis technique, more and more surgeons have begun incorporating this skill set into their practice.3, 5 Multiple retrospective studies comparing laparoscopic and open techniques have shown that laparoscopic adhesiolysis yields earlier return of bowel function, shorter hospital stays, reduced incidence of adhesion formation, and reduced incidence of incisional hernia formation postoperatively.6–10
Author Manuscript
We decided to evaluate our patient population at the University of Virginia by comparing outcomes between laparoscopic and open adhesiolysis for the treatment of SBO and chronic abdominal pain. We hypothesized that patients undergoing laparoscopic adhesiolysis for chronic abdominal pain and SBO would have decreased postoperative morbidity and 30-day mortality.
Methods Patients
Author Manuscript
Institutional Review Board approval was obtained before retrospective review of the data was initiated. This was a retrospective cohort study of all patients admitted to the University of Virginia between June 2000 and October 2011 with the primary treatment diagnosis of lysis of adhesions. Patients were identified by querying the hospital database for Current Procedural Terminology (CPT, a registered trademark of the American Medical Association) codes 44005 (lysis of adhesions) and 44180 (laparoscopic lysis of adhesions). Dates were chosen largely based on the availability of CPT codes and data provided by electronic medical records. Individual patients were then independently reviewed by a panel of five evaluators (S.W.D., J.R.G., C.A.G., T.E.N., and N.H.P.); discrepancies were resolved by consensus. Exclusion criteria consisted of operative reports in which lysis of adhesions were not associated with treatment for SBO and all children younger than 18 years of age. For example, patients were excluded if the primary surgeon coded bowel resection as the only procedure for the treatment of SBO. Demographic information, preoperative comorbidities, and postoperative outcomes for this final set of patients were then collected.
Author Manuscript
Patient demographics and comorbidities evaluated included age, gender, body mass index (BMI), tobacco abuse, diabetes, steroid use, radiation, prior abdominal surgery, grade of small bowel obstruction, timing of surgical management, and perioperative wound contamination. These were chosen largely based on a report by Neumayer et al. In this report, Neumayer et al. lists 14 variables that have been independently linked with increased risk of surgical site infection.11
Am Surg. Author manuscript; available in PMC 2016 January 04.
Davies et al.
Page 3
Author Manuscript
Primary surgical outcomes evaluated included operating room (OR) times, intensive care unit (ICU) admission at the time of initial surgery, postoperative hospital length of stay (LOS), any surgical site complication occurring within 30 days of initial surgery (i.e., superficial surgical site infection, deep surgical site infection, organ space infection, seroma, and hematoma), any surgical site complication occurring after 30 days of initial surgery (i.e., superficial surgical site infection, deep surgical site infection, organ space infection, seroma, and hematoma), any relevant readmission, any relevant reoperation, and 30-day mortality. Definitions
Author Manuscript
Perioperative contamination was defined as the preoperative presence of an ostomy or fistula or intraoperative enteric spillage, enterotomy, or bowel resection. The grading of SBO (low-grade partial SBO, high-grade obstruction, or complete/closed loop obstruction) was based on information retrieved from chart reviews of the history and physical examination notes, daily progress notes, radiology notes, and operative reports. Our definitions were based on a consensus between definitions found within the literature and discussions with our radiologists. Low-grade partial SBO was defined as the sufficient ability of intraluminal liquid content and/or gas to pass through the point of obstruction. High-grade obstruction was defined as the persistent ability of some intraluminal liquid content and/or gas to pass through the point of obstruction, albeit delayed and diluted within the collapsed distal loops. Additionally, on plain film, multiple air–fluid levels and proximal small bowel distention may be appreciated. Complete/closed loop obstruction was defined as the inability of any intraluminal liquid content and/or gas to pass through the point of obstruction.12
Author Manuscript
Patients with complete or closed loop obstructions identified on computed tomography (CT) imaging; obstructions demonstrating free air, pneumatosis, or bowel wall thickening on CT imaging; or peritonitis as demonstrated on physical examination findings were immediately taken to the OR emergently (within 24 hours). Patients with partial loop obstructions were initially treated conservatively with nil per os, nasogastric tubing, intravenous fluids, Foley catheter, and serial abdominal examinations for a period of time as determined by patient response and surgical team preference. Elective management was defined as nonemergent surgical management of patients who had initially presented to our surgical clinic with chronic abdominal pain and who had been ruled out for SBO with radiographic imaging. Surgical management typically involved a diagnostic laparoscopy followed by laparoscopic adhesiolysis. Adhesiolysis Technique
Author Manuscript
Both adhesiolysis techniques (open and laparoscopic) were performed in a standard fashion primarily using sharp dissection. Electrocautery was used sparingly and judiciously. The entire small bowel was then examined, starting from the ligament of Treitz and running the bowel all the way down to the distal terminal ileum, looking for any additional adhesions or enterotomies. If an enterotomy was identified and there was no gross contamination or the diameter of the enterotomy was less than half the circumference of the small bowel, it was closed primarily. Otherwise, a short segment of bowel encompassing the enterotomy was resected and either primary anastomosis or an ostomy was performed.
Am Surg. Author manuscript; available in PMC 2016 January 04.
Davies et al.
Page 4
Statistical Analyses
Author Manuscript
Statistical analysis was performed using SAS Version 9.3 (Cary, NC) programming software. Statistical significance was defined as a P value of < 0.05. Univariate analysis of categorical data was performed using either χ2 or Fisher’s exact test depending on the size of data for each respective category (i.e., if any one cell in a 2 × 2 table was less than 5, Fisher’s exact test was used). Univariate analysis of continuous variables was performed using either independent t tests or Wilcoxon rank sum tests depending on the normalcy of distribution. These models were used to compare and contrast laparoscopic versus open adhesiolysis with regard to preoperative patient demographics and comorbidities and postoperative complications.
Author Manuscript
Additional univariate analyses were performed based on the disproportionate percentage of patients associated with high-grade bowel obstruction, conservative management (followed by surgery), and perioperative contamination within the open group as compared with the laparoscopic group. These stratified models were used to determine if an association existed between the disproportionate comorbidities and patient outcome. A subset analysis of patients managed laparoscopically compared with those initially managed laparoscopically but later converted to open was performed. Outcomes from this subset were also evaluated using univariate analyses to determine the complications that might arise from conversion. Finally, this subset analysis was then stratified by patients managed by surgeons trained in minimally invasive surgery (MIS). The purpose of this was to determine if additional training in MIS conferred any additional postoperative success.
Results Author Manuscript
Between June 2000 and October 2011, 414 patients were originally identified by CPT codes for lysis of adhesions and laparoscopic lysis of adhesions. Of those 414 patients, 24.6 per cent (n = 102) were included in this study based on the previously mentioned inclusion/ exclusion criteria. The types of SBO were as follows: low-grade partial SBO (54 of 102), high-grade obstruction (25 of 102), and complete/closed loop obstruction (23 of 102). Please refer to Figures 1 and 2 for the corresponding grades of bowel obstruction broken down by management style and the bowel obstruction etiology, respectively.
Author Manuscript
Of the 102 patients, 62.7 per cent (n = 64) underwent open adhesiolysis and 37.3 per cent (n = 38) underwent laparoscopic. All statistical calculations for patients undergoing laparoscopic adhesiolysis have incorporated patients who were converted from laparoscopic to open unless otherwise stated. Patient demographics and comorbidities were comparable between the two groups; however, the open adhesiolysis group had a significantly higher incidence of high-grade bowel obstruction, patients who were initially managed conservatively but followed by surgery, and perioperative wound contamination. The laparoscopic groups had a significantly higher BMI and incidence of patients undergoing elective management (Table 1). Postoperative outcomes were comparable between the two
Am Surg. Author manuscript; available in PMC 2016 January 04.
Davies et al.
Page 5
Author Manuscript
groups; however, the open adhesiolysis group had a significantly higher incidence of ICU admission postoperatively and longer LOS (Table 2). Patients stratified by perioperative contamination were significantly more likely to be associated with longer OR times, a higher incidence of ICU admission, a longer LOS, a higher incidence of superficial surgical site infection (SSI) within 30 days of surgery, a higher incidence of deep SSI within 30 days of surgery, a higher incidence of superficial SSI after 30 days, a higher incidence of readmission postoperatively, and a higher incidence of reoperation postoperatively (Table 3). Patients stratified by high-grade bowel obstruction had similar surgical outcomes as compared with low-grade partial SBO (Table 4). Patients stratified by conservative management followed by surgery had a longer LOS as compared with those managed electively (Table 5).
Author Manuscript
Of the 38 patients who underwent laparoscopic adhesiolysis, 26.3 per cent (n = 10) were converted to open for the following reasons: dense adhesions (seven of 10), enterotomy (one of 10), excess bleeding (one of 10), and bowel mass (one of 10). Patient demographics and comorbidities were similar; however, there was a significantly higher percentage of tobacco use among the laparoscopic converted to open group (Table 6). Postoperative outcomes were comparable; however, the laparoscopic converted to open group was associated with a significantly longer OR time, higher incidence of superficial SSI within 30 days of surgery, and a higher incidence of superficial SSI after 30 days (Table 7).
Author Manuscript
Finally, adhesiolysis was performed by 33 different surgeons trained in general, MIS, transplant, hepatobiliary, colorectal, endocrine, breast, and acute care surgery. Of the 38 laparoscopic adhesiolysis surgeries performed, 71.1 per cent (n = 27) were carried out by surgeons trained inMIS. Laparoscopic patients stratified according to MIS-trained surgeons had similar postoperative outcomes as compared with those treated by surgeons not trained in MIS (Table 8).
Discussion
Author Manuscript
Adhesions can be the source of significant morbidity and mortality for millions of individuals worldwide through bowel obstruction, pelvic pain, and secondary female infertility.13 Previous studies have shown that intra-abdominal adhesions develop in 60 to 90 per cent of patients who have had one or more prior abdominal surgeries and in 10 to 30 per cent of patients who have not.6, 14–16 Menzies et al., in a study evaluating 2708 adult laparotomies, found that within 1 month, approximately 0.52 per cent required additional surgery for adhesion-related obstruction. This number rose to approximately 0.96 per cent within one year.14 If adhesiolysis is then subsequently performed, adhesion reformation occurs anywhere from 55 to 100 per cent of the time.1 A review by van Goor determined that adhesion formation may be attributed to many factors such as type of incision (length, location, vertical, horizontal, etc.), number of previous laparotomies (increased laparotomies equals increased adhesions), damaged visceral or parietal peritoneum, intraoperative complications at initial laparotomy, and whether the surgery was open or laparoscopic.15 Van Goor also commented that adhesions subsequently contribute to increased trocar placement-related injuries, adhesiolysis time, intraoperative complications (i.e., bleeding,
Am Surg. Author manuscript; available in PMC 2016 January 04.
Davies et al.
Page 6
Author Manuscript
enterotomy and enterectomy damage to intra-abdominal viscera), conversion from laparoscopy to open, postoperative morbidity and mortality (i.e., hematoma, intra-abdominal abscess, fistula formation, and wound infection), and hospital LOS.15 Our study showed that, of 102 patients, 96 had at least one prior abdominal surgery.
Author Manuscript
In our study, the open adhesiolysis group was associated with a higher incidence of ICU admission and longer, postoperative LOS as compared with the laparoscopic group. This could potentially be associated with the fact that a higher number of patients in this group underwent conservative treatment followed by surgery, which was shown by stratified analysis to be associated with a significantly longer postoperative LOS. A recent analysis by Joseph et al. determined that delaying surgical treatment by as little as 48 hours resulted in significantly longer return of bowel function, longer hospital LOS after surgery, and postoperative morbidity.17 Conservative management in our study, on average, lasted approximately 7.38 ± 7.74 days before being deemed as a failure and initiating surgical management. It is also of note that there was a larger cohort of laparoscopic patients managed on an elective basis as compared with the open group potentially indicating a less severe obstruction and/or morbidity status.
Author Manuscript
Our open adhesiolysis patient population was also associated with a higher incidence of perioperative contamination as compared with the laparoscopic group, which was shown by stratified analysis to be associated with a significantly longer OR time, a higher incidence of ICU admission, a longer postoperative LOS, a higher incidence of superficial SSI, a higher incidence of deep SSI, a higher readmission rate, and a higher reoperation rate. A recent analysis by Margenthaler et al. determined that bowel resection during adhesiolysis as compared with adhesiolysis alone was associated with a significantly higher incidence of postoperative morbidity (i.e., prolonged ICU stay and surgical site infection).18 As mentioned previously, perioperative contamination in our study was defined as the presence of an ostomy, fistula, enterotomy, gross stool leakage, or bowel resection.
Author Manuscript
Although it may be difficult to compare our laparoscopic and open adhesiolysis groups as a result of the findings mentioned, the demographics and comorbidities of our laparoscopic and laparoscopic converted to open adhesiolysis groups were similar. Patients who were initially managed laparoscopically but were later converted to open adhesiolysis experienced significantly longer OR times and higher incidences of SSI. Although major causes of laparoscopic conversion for our study included adhesion density, enterotomy, and bleeding, it is important to note that our incidence of intraoperative enterotomy was 11.5 and 23.4 per cent for the laparoscopic and open groups, respectively. This is compared with the 3 to 17.6 per cent reported within the literature for laparoscopic adhesiolysis.6, 19 A subset analysis of these patients stratified by patients who were operated on by MIS-trained surgeons determined that additional training in MIS did not confer any additional advantage regarding postoperative outcome. We interpret these findings to indicate that given the advancement in laparoscopic training of general surgery residents, fellowship training in MIS should not dictate laparoscopic management regarding adhesiolysis for SBO.20, 21
Am Surg. Author manuscript; available in PMC 2016 January 04.
Davies et al.
Page 7
Author Manuscript
Limitations
Author Manuscript Author Manuscript
One of our study limitations is the fact that this is a retrospective cohort analysis and thus is subject to selection bias, potentially confounding the interpretation of outcomes between two study groups. An additional limitation is the fact that five different surgical residents compiled this database. This increases the risk of variability between recorded information as well as data entry errors. To minimize this risk, as mentioned previously, all discrepancies were addressed by consensus. Another limitation is the fact that this is a single-center study. As a result, external validity may be limited in generalizing results to other areas because the demographics and comorbidities of our patient population may differ. Another limitation of our study regards the small patient size. Small sample size limits the power of a study, which in turn increases the risk of making a Type II error (the odds of saying there is no treatment effect when in fact there is one). Additionally, small patient size limited our ability to perform a multivariate analysis and thus more closely analyze discrepancies between the open and laparoscopic groups with regard to preoperative risk factors and comorbidities. Small sample size was most likely the result of the limitations of using CPT coding to identify cases. To improve our power for future analysis, we will most likely use International Classification of Diseases, 9th Revision codes to identify patients based on bowel obstruction. From here we will then parcel out those who were surgically managed. This should help to include patients who may not have been identified using CPT codes as a result of a surgeon coding, for example, a bowel resection rather than adhesiolysis. Finally, a total of 33 surgeons were responsible for carrying out the previously mentioned 102 surgeries. Many of these surgeons were trained in different fields of expertise (i.e., general, MIS, transplant, hepatobiliary, colorectal, endocrine, breast, and acute care surgery, etc.). This potentially limits the internal validity given the fact that different surgeons may carry out adhesiolysis in a different fashion depending on background training; however, it does serve to strengthen the external validity.
Conclusion
Author Manuscript
Our study demonstrated a benefit of laparoscopic adhesiolysis for the management of SBO over the open approach regarding fewer incidences of ICU admission and shorter LOS; however, selection bias as previously mentioned was a significant contributing factor. Based on the preceding evidence, caution should be taken when considering the optimum approach and postoperative care for adhesiolysis regarding patients with SBO with perioperative wound contamination because these patients were shown to be associated with longer OR times, higher rates of ICU admission, longer LOS, and higher rates of SSI necessitating readmission and reoperation. Additionally, although we now have the ability to conservatively manage some of these patients for indefinite periods of time, the adage of “never letting the sun go down on an obstruction” should still be at the forefront of our thoughts because prolonged conservative management was shown to be associated with longer LOS in our study. Maybe the solution lies somewhere in between involving immediate decompression followed by surgery within 24 to 48 hours. Finally, whenever possible, laparoscopic management of these patients, regardless of surgeon training, should be given priority to minimize the incisional site and reduce the formation and/or prevalence of adhesions and subsequent development of another SBO. Am Surg. Author manuscript; available in PMC 2016 January 04.
Davies et al.
Page 8
Author Manuscript
REFERENCES
Author Manuscript Author Manuscript Author Manuscript
1. Diamond MP, Freeman ML. Clinical implications of postsurgical adhesions. Hum Reprod Update. 2001; 7:567–576. [PubMed: 11727865] 2. Alkhoury, F.; Helton, W. Intestinal Obstruction. In: Fink, M.; Jurkovich, G.; Kaiser, L., et al., editors. ACS Surgery: Principles and Practice. 6th. New York, NY: WebMD Professional Publishing; 2007. p. 514-533. 3. Cirocchi R, Abraha I, Farinella E, et al. Laparoscopic versus open surgery in small bowel obstruction. Cochrane Database Syst Rev. 2010; 2:CD007511. [PubMed: 20166096] 4. Tavakkolizadeh, A.; Whang, E.; Ashley, S., et al. Small Bowel Obstruction. In: Brunicardi, F.; Anderson, D.; Billiar, T., et al., editors. Schwartz’s Principles of Surgery. 9th. New York, NY: McGraw-Hill; 2009. p. 988-993. 5. Clotteau JE, Premont M. Occlusion by adhesions treated by celioscopic section. Presse Med. 1990; 19:1196. [in French]. [PubMed: 1694997] 6. Szomstein S, Lo Menzo E, Simpfendorfer C, et al. Laparoscopic lysis of adhesions. World J Surg. 2006; 30:535–540. [PubMed: 16555020] 7. Campbell, K. Small Bowel Obstruction. In: Scheidt, S.; Voit, F., editors. Current Surgical Therapy. 9th. Philadelphia, PA: Mosby Elsevier; 2008. p. 117-120. 8. Strickland P, Lourie DJ, Suddleson EA, et al. Is laparoscopy safe and effective for treatment of acute small-bowel obstruction? Surg Endosc. 1999; 13:695–698. [PubMed: 10384077] 9. Qureshi I, Awad ZT. Predictors of failure of the laparoscopic approach for the management of small bowel obstruction. Am Surg. 2010; 76:947–950. [PubMed: 20836340] 10. Wullstein C, Gross E. Laparoscopic compared with conventional treatment of acute adhesive small bowel obstruction. Br J Surg. 2003; 90:1147–1151. [PubMed: 12945085] 11. Neumayer L, Hosokawa P, Itani K, et al. Multivariable predictors of postoperative surgical site infection after general and vascular surgery: results from the patient safety in surgery study. J Am Coll Surg. 2007; 204:1178–1187. [PubMed: 17544076] 12. Silva AC, Pimenta M, Guimaraes LS. Small bowel obstruction: what to look for. Radiographics. 2009; 29:423–439. [PubMed: 19325057] 13. Liakakos T, Thomakos N, Fine PM, et al. Peritoneal adhesions: etiology, pathophysiology, and clinical significance. Recent advances in prevention and management. Dig Surg. 2001; 18:260– 273. [PubMed: 11528133] 14. Menzies D, Ellis H. Intestinal obstruction from adhesions—how big is the problem? Ann R Coll Surg Engl. 1990; 72:60–63. [PubMed: 2301905] 15. van Goor H. Consequences and complications of peritoneal adhesions. Colorectal Dis. 2007; 9(suppl 2):25–34. [PubMed: 17824967] 16. Weibel MA, Majno G. Peritoneal adhesions and their relation to abdominal surgery. A postmortem study. Am J Surg. 1973; 126:345–353. [PubMed: 4580750] 17. Joseph SP, Simonson M, Edwards C. ’Let’s just wait one more day’: impact of timing on surgical outcome in the treatment of adhesion-related small bowel obstruction. Am Surg. 2013; 79:175– 179. [PubMed: 23336657] 18. Margenthaler JA, Longo WE, Virgo KS, et al. Risk factors for adverse outcomes following surgery for small bowel obstruction. Ann Surg. 2006; 243:456–464. [PubMed: 16552195] 19. O’Connor DB, Winter DC. The role of laparoscopy in the management of acute small-bowel obstruction: a review of over 2,000 cases. Surg Endosc. 2012; 26:12–17. [PubMed: 21898013] 20. Hallowell PT, Dahman MI, Stokes JB, et al. Minimally invasive surgery fellowship does not adversely affect general surgery resident case volume: a decade of experience. Am J Surg. 2013; 205:307–311. discussion 311. [PubMed: 23414954] 21. Unawane A, Kamyab A, Patel M, et al. Changing paradigms in minimally invasive surgery training. Am J Surg. 2013; 205:284–288. discussion 288. [PubMed: 23351509]
Am Surg. Author manuscript; available in PMC 2016 January 04.
Davies et al.
Page 9
Author Manuscript Author Manuscript
Fig. 1.
Grades of bowel obstruction broken down by management style.
Author Manuscript Author Manuscript Am Surg. Author manuscript; available in PMC 2016 January 04.
Davies et al.
Page 10
Author Manuscript Author Manuscript
Fig. 2.
Bowel obstruction etiology.
Author Manuscript Author Manuscript Am Surg. Author manuscript; available in PMC 2016 January 04.
Davies et al.
Page 11
Table 1
Author Manuscript
Univariable Analysis of Patient Demographics and Comorbidities in the Laparoscopic and Open Adhesiolysis Groups* Demographic/Comorbidity Age (years)
Lap (n = 38)
Open (n = 64)
P Value
52.5(43.0–57.0)
57.0 (42.5–71.0)
0.1558
13 (34.2%)
28(43.8%)
0.3421
Gender (male) BMI
27(21–29.22)
22.43(19.23–25.59)
0.0423
Tobacco
8 (21.1%)
13 (20.3%)
0.9288
Diabetes
10 (26.3%)
15 (23.4%)
0.7439
Steroids
1 (2.6%)
8 (12.5%)
0.1482
1 (2.6%)
4 (6.3%)
0.6483
34 (89.5%)
62 (96.9%)
0.1921
Radiation Prior abdominal surgery Number of prior abdominal surgeries
Author Manuscript
1 (1–3)
2 (1–3)
0.0627
Partial small bowel obstruction
21 (55.3%)
33 (51.6%)
0.8378
High-grade bowel obstruction
8 (21.1%)
17 (26.6%)
0.0018
Complete obstruction
9 (23.7%)
14 (21.9%)
1.0000
Elective surgery
9 (23.7%)
4 (6.3%)
0.0149
Conservative management
14 (36.8%)
40 (62.5%)
0.0145
Emergent surgery
15 (39.5%)
20 (31.3%)
0.5179
Perioperative contamination
8 (21.1%)
36 (56.3%)
0.0005
*
Categorical data reported as number (%); χ2 or Fisher’s exact test was used depending on the size of the data for each respective variable (i.e., if any one cell in a 2 × 2 table was less than 5, Fisher’s exact test was used). Continuous data reported as either mean ± standard deviation or median (first quartile, third quartile) depending on the normalcy of distribution; Student’s t test or Wilcoxon rank sum was used depending on the normalcy of distribution. Lap, laparoscopic; BMI, body mass index.
Author Manuscript Author Manuscript Am Surg. Author manuscript; available in PMC 2016 January 04.
Davies et al.
Page 12
Table 2
Author Manuscript
Univariable Analysis of Surgical Outcomes in the Laparoscopic and Open Adhesiolysis Groups* Outcome OR time (minutes) ICU admission LOS (days) Superficial SSI < 30 days Deep SSI < 30 days Organ space SSI < 30 days Seroma < 30 days
t
Open (n = 64)
P Value
93 (65–123)
110.5 (62.0–187.5)
0.1096
2 (5.3%)
14 (21.9%)
0.0257
3.5 (2.0–6.0)
9 (5–15)
30 days
4 (10.5%)
10 (15.6%)
0.4694
Deep SSI > 30 days
1 (2.6%)
5 (7.8%)
0.4073
0 (0%)
4 (6.3%)
0.2939
1 (2.6%)
0 (0%)
0.3725
0 (0%)
1 (1.6%)
1.0000
Readmission
8 (21.1%)
19 (29.7%)
0.3392
Reoperation
6 (15.8%)
14 (21.9%)
0.4542
0 (0%)
3 (4.7%)
0.2918
Organ space SSI > 30 days Seroma > 30 days Hematoma > 30 days
30-day mortality *
Categorical data reported as number (%); χ2 or Fisher’s exact test was used depending on the size of the data for each respective variable (i.e., if any one cell in a 2 × 2 table was less than 5, Fisher’s exact test was used). Continuous data reported as either mean ± standard deviation or median (first quartile, third quartile) depending on the normalcy of distribution; Student’s t test or Wilcoxon rank sum was used depending on the normalcy of distribution. OR, operating room; ICU, intensive care unit; LOS, postoperative hospital length of stay; SSI, surgical site infection.
Author Manuscript Author Manuscript Am Surg. Author manuscript; available in PMC 2016 January 04.
Davies et al.
Page 13
Table 3
Author Manuscript
Univariable Analysis of Surgical Outcomes in Patients with Perioperative Contamination* Outcome OR time (minutes)
No Perioperative Contamination (n = 58)
Perioperative Contamination (n = 44)
P Value
72 (46–116)
135.5 (101.5–190.5)
30 days
1 (1.7%)
5 (11.4%)
0.0821
Organ space SSI > 30 days
1 (1.7%)
3 (6.8%)
0.3125
Seroma > 30 days
1 (1.7%)
0 (0%)
1.0000
0 (0%)
1 (2.3%)
0.4314
Readmission
11 (19.0%)
16 (36.4%)
0.0485
Reoperation
6 (10.3%)
14 (31.8%)
0.0068
30-day mortality
2 (3.5%)
1 (2.3%)
1.0000
Hematoma > 30 days
*
Categorical data reported as number (%); χ2 or Fisher’s exact test was used depending on the size of the data for each respective variable (i.e., if any one cell in a 2 × 2 table was less than 5, Fisher’s exact test was used). Continuous data reported as either mean ± standard deviation or median (first quartile, third quartile) depending on the normalcy of distribution; Student’s t test or Wilcoxon rank sum was used depending on the normalcy of distribution. OR, operating room; ICU, intensive care unit; LOS, postoperative hospital length of stay; SSI, surgical site infection.
Author Manuscript Author Manuscript Am Surg. Author manuscript; available in PMC 2016 January 04.
Davies et al.
Page 14
Table 4
Author Manuscript
Univariable Analysis of Surgical Outcomes in Patients with High-grade Bowel Obstructions as Compared with Partial Small Bowel Obstruction* Outcome OR time (minutes) ICU admission LOS (days)
PSBO (n = 54)
HGBO (n = 25)
P Value
107(65–145)
95(51–156)
0.4244
8 (14.8%)
7 (28%)
0.2186
6 (3–14)
9 (5–13)
0.3013
15 (27.8%)
5 (20%)
0.4596
Deep SSI < 30 days
5 (9.3%)
0 (0%)
0.1730
Organ space SSI < 30 days
3 (5.6%)
0 (0%)
0.5476
Seroma < 30 days
1 (1.9%)
2 (8%)
0.2339
Hematoma < 30 days
3 (5.6%)
0 (0%)
0.5476
Superficial SSI > 30 days
9 (16.7%)
4 (16%)
1.0000
Deep SSI > 30 days
4 (7.4%)
1 (4%)
1.0000
Organ space SSI > 30 days
2 (3.7%)
0 (0%)
1.0000
0 (0%)
1 (4%)
0.3165
Superficial SSI < 30 days
Author Manuscript
Seroma > 30 days Hematoma > 30 days
1 (1.9%)
0 (0%)
1.0000
Readmission
14 (25.9%)
4 (16%)
0.3280
Reoperation
8 (14.8%)
4 (16%)
1.0000
30-day mortality
1 (1.9%)
0 (0%)
1.0000
*
Categorical data reported as number (%); χ2 or Fisher’s exact test was used depending on the size of the data for each respective variable (i.e., if any one cell in a 2 × 2 table was less than 5, Fisher’s exact test was used). Continuous data reported as either mean ± standard deviation or median (first quartile, third quartile) depending on the normalcy of distribution; Student’s t test or Wilcoxon rank sum was used depending upon the normalcy of distribution.
Author Manuscript
PSBO, partial small bowel obstruction; HGBO, high-grade bowel obstruction; OR, operating room; ICU, intensive care unit; LOS, postoperative hospital length of stay; SSI, surgical site infection.
Author Manuscript Am Surg. Author manuscript; available in PMC 2016 January 04.
Davies et al.
Page 15
Table 5
Author Manuscript
Univariable Analysis of Surgical Outcomes in Patients Managed Conservatively (followed by surgery) as Compared with Patients Managed Electively* Outcome
Elective (n = 13)
Conservative (n = 54)
P Value
OR time (minutes)
104(72.5–161.5)
104.5(61–158)
0.8167
1 (7.7%)
10 (18.5%)
0.6772
ICU admission LOS (days)
2 (0–5)
9 (5–17)
Am Surg. Author manuscript; available in PMC 2016 January 04. Published in final edited form as: Am Surg. 2014 March ; 80(3): 261–269.
A Comparative Analysis between Laparoscopic and Open Adhesiolysis at a Tertiary Care Center Stephen W. Davies, M.D., M.P.H., Jake R. Gillen, M.D., Christopher A. Guidry, M.D., M.S., Timothy E. Newhook, M.D., Nicolas H. Pope, M.D., Tjasa Hranjec, M.D., M.S., Robert G. Sawyer, M.D., and Peter T. Hallowell, M.D. University of Virginia School of Medicine, Charlottesville, Virginia
Author Manuscript
Abstract
Author Manuscript
Laparotomy has been the favored approach regarding surgical management of small bowel obstruction (SBO); however, laparoscopy may offer improved outcomes. Patients undergoing laparoscopic lysis of adhesions (LOA) at our institution for SBO will have lower postoperative morbidity and 30-day mortality. Patients undergoing LOA at our institution, from 2000 to 2011, were reviewed. Categorical data were analyzed with χ2 or Fisher’s exact tests. Continuous data were analyzed with Student’s t test or Wilcoxon rank sum. One hundred two (38 laparoscopic, 64 open) LOA cases were selected. Perioperative contamination and conservative management were higher in the open group. Open cases had a greater incidence of intensive care unit (ICU) admissions and longer length of stay. Stratified analysis determined a strong association between perioperative contamination and a higher incidence of ICU admission, perioperative contamination and longer LOS, and conservative management and longer LOS. Finally, patient outcome did not differ between those treated by surgeons trained in minimally invasive surgery (MIS) compared with those not trained in MIS. Careful consideration of surgical approach and timing is called for in all patients with SBO; however, whenever possible, laparoscopic preference should be given to most patients in an expeditious fashion irrespective of MIS training.
Author Manuscript
Intestinal obstruction is one of the more frequently encountered disorders of the small bowel and contributes to a large number of annual hospital admissions and subsequent financial expenditures. A study in 2001 identified that, in the United States alone, over $1 billion was spent on bowel obstruction in 1994.1 Intestinal obstruction is most commonly associated with gastrointestinal paralysis (ileus) secondary to bowel inflammation that may be attributable to surgery, medication, or inflammatory bowel disease. A smaller percentage is associated with mechanical compression, either intrinsic or extrinsic.2 Regarding mechanical small bowel obstruction (SBO), 65 per cent of cases, on average, are attributable to intraabdominal adhesions.3 Adhesions have been previously defined as “abnormal fibrous connections that may contain vascular channels, which join surfaces in abnormal locations.”1 Previously, the primary etiology of obstruction was considered to be external
Address correspondence and reprint requests to Stephen W. Davies, M.D., 4008 Cindi Lane, Winterville, NC 28590. [email protected]. Presented as a gold medal podium presentation at the 2013 Southeastern Surgical Congress, Annual Scientific Meeting, Jacksonville, FL, February 9–12, 2013.
Davies et al.
Page 2
Author Manuscript
hernia incarceration with subsequent development of strangulation. However, as abdominopelvic surgery has evolved, so has the development of adhesion-related obstruction, which is now considered to be the primary cause.1 It is estimated that over 300,000 patients are hospitalized and undergo surgery for adhesion-related SBO annually.4 Open adhesiolysis through a midline laparotomy incision is considered to be the standard approach; however, since 1990 when Clotteau described the first laparoscopic adhesiolysis technique, more and more surgeons have begun incorporating this skill set into their practice.3, 5 Multiple retrospective studies comparing laparoscopic and open techniques have shown that laparoscopic adhesiolysis yields earlier return of bowel function, shorter hospital stays, reduced incidence of adhesion formation, and reduced incidence of incisional hernia formation postoperatively.6–10
Author Manuscript
We decided to evaluate our patient population at the University of Virginia by comparing outcomes between laparoscopic and open adhesiolysis for the treatment of SBO and chronic abdominal pain. We hypothesized that patients undergoing laparoscopic adhesiolysis for chronic abdominal pain and SBO would have decreased postoperative morbidity and 30-day mortality.
Methods Patients
Author Manuscript
Institutional Review Board approval was obtained before retrospective review of the data was initiated. This was a retrospective cohort study of all patients admitted to the University of Virginia between June 2000 and October 2011 with the primary treatment diagnosis of lysis of adhesions. Patients were identified by querying the hospital database for Current Procedural Terminology (CPT, a registered trademark of the American Medical Association) codes 44005 (lysis of adhesions) and 44180 (laparoscopic lysis of adhesions). Dates were chosen largely based on the availability of CPT codes and data provided by electronic medical records. Individual patients were then independently reviewed by a panel of five evaluators (S.W.D., J.R.G., C.A.G., T.E.N., and N.H.P.); discrepancies were resolved by consensus. Exclusion criteria consisted of operative reports in which lysis of adhesions were not associated with treatment for SBO and all children younger than 18 years of age. For example, patients were excluded if the primary surgeon coded bowel resection as the only procedure for the treatment of SBO. Demographic information, preoperative comorbidities, and postoperative outcomes for this final set of patients were then collected.
Author Manuscript
Patient demographics and comorbidities evaluated included age, gender, body mass index (BMI), tobacco abuse, diabetes, steroid use, radiation, prior abdominal surgery, grade of small bowel obstruction, timing of surgical management, and perioperative wound contamination. These were chosen largely based on a report by Neumayer et al. In this report, Neumayer et al. lists 14 variables that have been independently linked with increased risk of surgical site infection.11
Am Surg. Author manuscript; available in PMC 2016 January 04.
Davies et al.
Page 3
Author Manuscript
Primary surgical outcomes evaluated included operating room (OR) times, intensive care unit (ICU) admission at the time of initial surgery, postoperative hospital length of stay (LOS), any surgical site complication occurring within 30 days of initial surgery (i.e., superficial surgical site infection, deep surgical site infection, organ space infection, seroma, and hematoma), any surgical site complication occurring after 30 days of initial surgery (i.e., superficial surgical site infection, deep surgical site infection, organ space infection, seroma, and hematoma), any relevant readmission, any relevant reoperation, and 30-day mortality. Definitions
Author Manuscript
Perioperative contamination was defined as the preoperative presence of an ostomy or fistula or intraoperative enteric spillage, enterotomy, or bowel resection. The grading of SBO (low-grade partial SBO, high-grade obstruction, or complete/closed loop obstruction) was based on information retrieved from chart reviews of the history and physical examination notes, daily progress notes, radiology notes, and operative reports. Our definitions were based on a consensus between definitions found within the literature and discussions with our radiologists. Low-grade partial SBO was defined as the sufficient ability of intraluminal liquid content and/or gas to pass through the point of obstruction. High-grade obstruction was defined as the persistent ability of some intraluminal liquid content and/or gas to pass through the point of obstruction, albeit delayed and diluted within the collapsed distal loops. Additionally, on plain film, multiple air–fluid levels and proximal small bowel distention may be appreciated. Complete/closed loop obstruction was defined as the inability of any intraluminal liquid content and/or gas to pass through the point of obstruction.12
Author Manuscript
Patients with complete or closed loop obstructions identified on computed tomography (CT) imaging; obstructions demonstrating free air, pneumatosis, or bowel wall thickening on CT imaging; or peritonitis as demonstrated on physical examination findings were immediately taken to the OR emergently (within 24 hours). Patients with partial loop obstructions were initially treated conservatively with nil per os, nasogastric tubing, intravenous fluids, Foley catheter, and serial abdominal examinations for a period of time as determined by patient response and surgical team preference. Elective management was defined as nonemergent surgical management of patients who had initially presented to our surgical clinic with chronic abdominal pain and who had been ruled out for SBO with radiographic imaging. Surgical management typically involved a diagnostic laparoscopy followed by laparoscopic adhesiolysis. Adhesiolysis Technique
Author Manuscript
Both adhesiolysis techniques (open and laparoscopic) were performed in a standard fashion primarily using sharp dissection. Electrocautery was used sparingly and judiciously. The entire small bowel was then examined, starting from the ligament of Treitz and running the bowel all the way down to the distal terminal ileum, looking for any additional adhesions or enterotomies. If an enterotomy was identified and there was no gross contamination or the diameter of the enterotomy was less than half the circumference of the small bowel, it was closed primarily. Otherwise, a short segment of bowel encompassing the enterotomy was resected and either primary anastomosis or an ostomy was performed.
Am Surg. Author manuscript; available in PMC 2016 January 04.
Davies et al.
Page 4
Statistical Analyses
Author Manuscript
Statistical analysis was performed using SAS Version 9.3 (Cary, NC) programming software. Statistical significance was defined as a P value of < 0.05. Univariate analysis of categorical data was performed using either χ2 or Fisher’s exact test depending on the size of data for each respective category (i.e., if any one cell in a 2 × 2 table was less than 5, Fisher’s exact test was used). Univariate analysis of continuous variables was performed using either independent t tests or Wilcoxon rank sum tests depending on the normalcy of distribution. These models were used to compare and contrast laparoscopic versus open adhesiolysis with regard to preoperative patient demographics and comorbidities and postoperative complications.
Author Manuscript
Additional univariate analyses were performed based on the disproportionate percentage of patients associated with high-grade bowel obstruction, conservative management (followed by surgery), and perioperative contamination within the open group as compared with the laparoscopic group. These stratified models were used to determine if an association existed between the disproportionate comorbidities and patient outcome. A subset analysis of patients managed laparoscopically compared with those initially managed laparoscopically but later converted to open was performed. Outcomes from this subset were also evaluated using univariate analyses to determine the complications that might arise from conversion. Finally, this subset analysis was then stratified by patients managed by surgeons trained in minimally invasive surgery (MIS). The purpose of this was to determine if additional training in MIS conferred any additional postoperative success.
Results Author Manuscript
Between June 2000 and October 2011, 414 patients were originally identified by CPT codes for lysis of adhesions and laparoscopic lysis of adhesions. Of those 414 patients, 24.6 per cent (n = 102) were included in this study based on the previously mentioned inclusion/ exclusion criteria. The types of SBO were as follows: low-grade partial SBO (54 of 102), high-grade obstruction (25 of 102), and complete/closed loop obstruction (23 of 102). Please refer to Figures 1 and 2 for the corresponding grades of bowel obstruction broken down by management style and the bowel obstruction etiology, respectively.
Author Manuscript
Of the 102 patients, 62.7 per cent (n = 64) underwent open adhesiolysis and 37.3 per cent (n = 38) underwent laparoscopic. All statistical calculations for patients undergoing laparoscopic adhesiolysis have incorporated patients who were converted from laparoscopic to open unless otherwise stated. Patient demographics and comorbidities were comparable between the two groups; however, the open adhesiolysis group had a significantly higher incidence of high-grade bowel obstruction, patients who were initially managed conservatively but followed by surgery, and perioperative wound contamination. The laparoscopic groups had a significantly higher BMI and incidence of patients undergoing elective management (Table 1). Postoperative outcomes were comparable between the two
Am Surg. Author manuscript; available in PMC 2016 January 04.
Davies et al.
Page 5
Author Manuscript
groups; however, the open adhesiolysis group had a significantly higher incidence of ICU admission postoperatively and longer LOS (Table 2). Patients stratified by perioperative contamination were significantly more likely to be associated with longer OR times, a higher incidence of ICU admission, a longer LOS, a higher incidence of superficial surgical site infection (SSI) within 30 days of surgery, a higher incidence of deep SSI within 30 days of surgery, a higher incidence of superficial SSI after 30 days, a higher incidence of readmission postoperatively, and a higher incidence of reoperation postoperatively (Table 3). Patients stratified by high-grade bowel obstruction had similar surgical outcomes as compared with low-grade partial SBO (Table 4). Patients stratified by conservative management followed by surgery had a longer LOS as compared with those managed electively (Table 5).
Author Manuscript
Of the 38 patients who underwent laparoscopic adhesiolysis, 26.3 per cent (n = 10) were converted to open for the following reasons: dense adhesions (seven of 10), enterotomy (one of 10), excess bleeding (one of 10), and bowel mass (one of 10). Patient demographics and comorbidities were similar; however, there was a significantly higher percentage of tobacco use among the laparoscopic converted to open group (Table 6). Postoperative outcomes were comparable; however, the laparoscopic converted to open group was associated with a significantly longer OR time, higher incidence of superficial SSI within 30 days of surgery, and a higher incidence of superficial SSI after 30 days (Table 7).
Author Manuscript
Finally, adhesiolysis was performed by 33 different surgeons trained in general, MIS, transplant, hepatobiliary, colorectal, endocrine, breast, and acute care surgery. Of the 38 laparoscopic adhesiolysis surgeries performed, 71.1 per cent (n = 27) were carried out by surgeons trained inMIS. Laparoscopic patients stratified according to MIS-trained surgeons had similar postoperative outcomes as compared with those treated by surgeons not trained in MIS (Table 8).
Discussion
Author Manuscript
Adhesions can be the source of significant morbidity and mortality for millions of individuals worldwide through bowel obstruction, pelvic pain, and secondary female infertility.13 Previous studies have shown that intra-abdominal adhesions develop in 60 to 90 per cent of patients who have had one or more prior abdominal surgeries and in 10 to 30 per cent of patients who have not.6, 14–16 Menzies et al., in a study evaluating 2708 adult laparotomies, found that within 1 month, approximately 0.52 per cent required additional surgery for adhesion-related obstruction. This number rose to approximately 0.96 per cent within one year.14 If adhesiolysis is then subsequently performed, adhesion reformation occurs anywhere from 55 to 100 per cent of the time.1 A review by van Goor determined that adhesion formation may be attributed to many factors such as type of incision (length, location, vertical, horizontal, etc.), number of previous laparotomies (increased laparotomies equals increased adhesions), damaged visceral or parietal peritoneum, intraoperative complications at initial laparotomy, and whether the surgery was open or laparoscopic.15 Van Goor also commented that adhesions subsequently contribute to increased trocar placement-related injuries, adhesiolysis time, intraoperative complications (i.e., bleeding,
Am Surg. Author manuscript; available in PMC 2016 January 04.
Davies et al.
Page 6
Author Manuscript
enterotomy and enterectomy damage to intra-abdominal viscera), conversion from laparoscopy to open, postoperative morbidity and mortality (i.e., hematoma, intra-abdominal abscess, fistula formation, and wound infection), and hospital LOS.15 Our study showed that, of 102 patients, 96 had at least one prior abdominal surgery.
Author Manuscript
In our study, the open adhesiolysis group was associated with a higher incidence of ICU admission and longer, postoperative LOS as compared with the laparoscopic group. This could potentially be associated with the fact that a higher number of patients in this group underwent conservative treatment followed by surgery, which was shown by stratified analysis to be associated with a significantly longer postoperative LOS. A recent analysis by Joseph et al. determined that delaying surgical treatment by as little as 48 hours resulted in significantly longer return of bowel function, longer hospital LOS after surgery, and postoperative morbidity.17 Conservative management in our study, on average, lasted approximately 7.38 ± 7.74 days before being deemed as a failure and initiating surgical management. It is also of note that there was a larger cohort of laparoscopic patients managed on an elective basis as compared with the open group potentially indicating a less severe obstruction and/or morbidity status.
Author Manuscript
Our open adhesiolysis patient population was also associated with a higher incidence of perioperative contamination as compared with the laparoscopic group, which was shown by stratified analysis to be associated with a significantly longer OR time, a higher incidence of ICU admission, a longer postoperative LOS, a higher incidence of superficial SSI, a higher incidence of deep SSI, a higher readmission rate, and a higher reoperation rate. A recent analysis by Margenthaler et al. determined that bowel resection during adhesiolysis as compared with adhesiolysis alone was associated with a significantly higher incidence of postoperative morbidity (i.e., prolonged ICU stay and surgical site infection).18 As mentioned previously, perioperative contamination in our study was defined as the presence of an ostomy, fistula, enterotomy, gross stool leakage, or bowel resection.
Author Manuscript
Although it may be difficult to compare our laparoscopic and open adhesiolysis groups as a result of the findings mentioned, the demographics and comorbidities of our laparoscopic and laparoscopic converted to open adhesiolysis groups were similar. Patients who were initially managed laparoscopically but were later converted to open adhesiolysis experienced significantly longer OR times and higher incidences of SSI. Although major causes of laparoscopic conversion for our study included adhesion density, enterotomy, and bleeding, it is important to note that our incidence of intraoperative enterotomy was 11.5 and 23.4 per cent for the laparoscopic and open groups, respectively. This is compared with the 3 to 17.6 per cent reported within the literature for laparoscopic adhesiolysis.6, 19 A subset analysis of these patients stratified by patients who were operated on by MIS-trained surgeons determined that additional training in MIS did not confer any additional advantage regarding postoperative outcome. We interpret these findings to indicate that given the advancement in laparoscopic training of general surgery residents, fellowship training in MIS should not dictate laparoscopic management regarding adhesiolysis for SBO.20, 21
Am Surg. Author manuscript; available in PMC 2016 January 04.
Davies et al.
Page 7
Author Manuscript
Limitations
Author Manuscript Author Manuscript
One of our study limitations is the fact that this is a retrospective cohort analysis and thus is subject to selection bias, potentially confounding the interpretation of outcomes between two study groups. An additional limitation is the fact that five different surgical residents compiled this database. This increases the risk of variability between recorded information as well as data entry errors. To minimize this risk, as mentioned previously, all discrepancies were addressed by consensus. Another limitation is the fact that this is a single-center study. As a result, external validity may be limited in generalizing results to other areas because the demographics and comorbidities of our patient population may differ. Another limitation of our study regards the small patient size. Small sample size limits the power of a study, which in turn increases the risk of making a Type II error (the odds of saying there is no treatment effect when in fact there is one). Additionally, small patient size limited our ability to perform a multivariate analysis and thus more closely analyze discrepancies between the open and laparoscopic groups with regard to preoperative risk factors and comorbidities. Small sample size was most likely the result of the limitations of using CPT coding to identify cases. To improve our power for future analysis, we will most likely use International Classification of Diseases, 9th Revision codes to identify patients based on bowel obstruction. From here we will then parcel out those who were surgically managed. This should help to include patients who may not have been identified using CPT codes as a result of a surgeon coding, for example, a bowel resection rather than adhesiolysis. Finally, a total of 33 surgeons were responsible for carrying out the previously mentioned 102 surgeries. Many of these surgeons were trained in different fields of expertise (i.e., general, MIS, transplant, hepatobiliary, colorectal, endocrine, breast, and acute care surgery, etc.). This potentially limits the internal validity given the fact that different surgeons may carry out adhesiolysis in a different fashion depending on background training; however, it does serve to strengthen the external validity.
Conclusion
Author Manuscript
Our study demonstrated a benefit of laparoscopic adhesiolysis for the management of SBO over the open approach regarding fewer incidences of ICU admission and shorter LOS; however, selection bias as previously mentioned was a significant contributing factor. Based on the preceding evidence, caution should be taken when considering the optimum approach and postoperative care for adhesiolysis regarding patients with SBO with perioperative wound contamination because these patients were shown to be associated with longer OR times, higher rates of ICU admission, longer LOS, and higher rates of SSI necessitating readmission and reoperation. Additionally, although we now have the ability to conservatively manage some of these patients for indefinite periods of time, the adage of “never letting the sun go down on an obstruction” should still be at the forefront of our thoughts because prolonged conservative management was shown to be associated with longer LOS in our study. Maybe the solution lies somewhere in between involving immediate decompression followed by surgery within 24 to 48 hours. Finally, whenever possible, laparoscopic management of these patients, regardless of surgeon training, should be given priority to minimize the incisional site and reduce the formation and/or prevalence of adhesions and subsequent development of another SBO. Am Surg. Author manuscript; available in PMC 2016 January 04.
Davies et al.
Page 8
Author Manuscript
REFERENCES
Author Manuscript Author Manuscript Author Manuscript
1. Diamond MP, Freeman ML. Clinical implications of postsurgical adhesions. Hum Reprod Update. 2001; 7:567–576. [PubMed: 11727865] 2. Alkhoury, F.; Helton, W. Intestinal Obstruction. In: Fink, M.; Jurkovich, G.; Kaiser, L., et al., editors. ACS Surgery: Principles and Practice. 6th. New York, NY: WebMD Professional Publishing; 2007. p. 514-533. 3. Cirocchi R, Abraha I, Farinella E, et al. Laparoscopic versus open surgery in small bowel obstruction. Cochrane Database Syst Rev. 2010; 2:CD007511. [PubMed: 20166096] 4. Tavakkolizadeh, A.; Whang, E.; Ashley, S., et al. Small Bowel Obstruction. In: Brunicardi, F.; Anderson, D.; Billiar, T., et al., editors. Schwartz’s Principles of Surgery. 9th. New York, NY: McGraw-Hill; 2009. p. 988-993. 5. Clotteau JE, Premont M. Occlusion by adhesions treated by celioscopic section. Presse Med. 1990; 19:1196. [in French]. [PubMed: 1694997] 6. Szomstein S, Lo Menzo E, Simpfendorfer C, et al. Laparoscopic lysis of adhesions. World J Surg. 2006; 30:535–540. [PubMed: 16555020] 7. Campbell, K. Small Bowel Obstruction. In: Scheidt, S.; Voit, F., editors. Current Surgical Therapy. 9th. Philadelphia, PA: Mosby Elsevier; 2008. p. 117-120. 8. Strickland P, Lourie DJ, Suddleson EA, et al. Is laparoscopy safe and effective for treatment of acute small-bowel obstruction? Surg Endosc. 1999; 13:695–698. [PubMed: 10384077] 9. Qureshi I, Awad ZT. Predictors of failure of the laparoscopic approach for the management of small bowel obstruction. Am Surg. 2010; 76:947–950. [PubMed: 20836340] 10. Wullstein C, Gross E. Laparoscopic compared with conventional treatment of acute adhesive small bowel obstruction. Br J Surg. 2003; 90:1147–1151. [PubMed: 12945085] 11. Neumayer L, Hosokawa P, Itani K, et al. Multivariable predictors of postoperative surgical site infection after general and vascular surgery: results from the patient safety in surgery study. J Am Coll Surg. 2007; 204:1178–1187. [PubMed: 17544076] 12. Silva AC, Pimenta M, Guimaraes LS. Small bowel obstruction: what to look for. Radiographics. 2009; 29:423–439. [PubMed: 19325057] 13. Liakakos T, Thomakos N, Fine PM, et al. Peritoneal adhesions: etiology, pathophysiology, and clinical significance. Recent advances in prevention and management. Dig Surg. 2001; 18:260– 273. [PubMed: 11528133] 14. Menzies D, Ellis H. Intestinal obstruction from adhesions—how big is the problem? Ann R Coll Surg Engl. 1990; 72:60–63. [PubMed: 2301905] 15. van Goor H. Consequences and complications of peritoneal adhesions. Colorectal Dis. 2007; 9(suppl 2):25–34. [PubMed: 17824967] 16. Weibel MA, Majno G. Peritoneal adhesions and their relation to abdominal surgery. A postmortem study. Am J Surg. 1973; 126:345–353. [PubMed: 4580750] 17. Joseph SP, Simonson M, Edwards C. ’Let’s just wait one more day’: impact of timing on surgical outcome in the treatment of adhesion-related small bowel obstruction. Am Surg. 2013; 79:175– 179. [PubMed: 23336657] 18. Margenthaler JA, Longo WE, Virgo KS, et al. Risk factors for adverse outcomes following surgery for small bowel obstruction. Ann Surg. 2006; 243:456–464. [PubMed: 16552195] 19. O’Connor DB, Winter DC. The role of laparoscopy in the management of acute small-bowel obstruction: a review of over 2,000 cases. Surg Endosc. 2012; 26:12–17. [PubMed: 21898013] 20. Hallowell PT, Dahman MI, Stokes JB, et al. Minimally invasive surgery fellowship does not adversely affect general surgery resident case volume: a decade of experience. Am J Surg. 2013; 205:307–311. discussion 311. [PubMed: 23414954] 21. Unawane A, Kamyab A, Patel M, et al. Changing paradigms in minimally invasive surgery training. Am J Surg. 2013; 205:284–288. discussion 288. [PubMed: 23351509]
Am Surg. Author manuscript; available in PMC 2016 January 04.
Davies et al.
Page 9
Author Manuscript Author Manuscript
Fig. 1.
Grades of bowel obstruction broken down by management style.
Author Manuscript Author Manuscript Am Surg. Author manuscript; available in PMC 2016 January 04.
Davies et al.
Page 10
Author Manuscript Author Manuscript
Fig. 2.
Bowel obstruction etiology.
Author Manuscript Author Manuscript Am Surg. Author manuscript; available in PMC 2016 January 04.
Davies et al.
Page 11
Table 1
Author Manuscript
Univariable Analysis of Patient Demographics and Comorbidities in the Laparoscopic and Open Adhesiolysis Groups* Demographic/Comorbidity Age (years)
Lap (n = 38)
Open (n = 64)
P Value
52.5(43.0–57.0)
57.0 (42.5–71.0)
0.1558
13 (34.2%)
28(43.8%)
0.3421
Gender (male) BMI
27(21–29.22)
22.43(19.23–25.59)
0.0423
Tobacco
8 (21.1%)
13 (20.3%)
0.9288
Diabetes
10 (26.3%)
15 (23.4%)
0.7439
Steroids
1 (2.6%)
8 (12.5%)
0.1482
1 (2.6%)
4 (6.3%)
0.6483
34 (89.5%)
62 (96.9%)
0.1921
Radiation Prior abdominal surgery Number of prior abdominal surgeries
Author Manuscript
1 (1–3)
2 (1–3)
0.0627
Partial small bowel obstruction
21 (55.3%)
33 (51.6%)
0.8378
High-grade bowel obstruction
8 (21.1%)
17 (26.6%)
0.0018
Complete obstruction
9 (23.7%)
14 (21.9%)
1.0000
Elective surgery
9 (23.7%)
4 (6.3%)
0.0149
Conservative management
14 (36.8%)
40 (62.5%)
0.0145
Emergent surgery
15 (39.5%)
20 (31.3%)
0.5179
Perioperative contamination
8 (21.1%)
36 (56.3%)
0.0005
*
Categorical data reported as number (%); χ2 or Fisher’s exact test was used depending on the size of the data for each respective variable (i.e., if any one cell in a 2 × 2 table was less than 5, Fisher’s exact test was used). Continuous data reported as either mean ± standard deviation or median (first quartile, third quartile) depending on the normalcy of distribution; Student’s t test or Wilcoxon rank sum was used depending on the normalcy of distribution. Lap, laparoscopic; BMI, body mass index.
Author Manuscript Author Manuscript Am Surg. Author manuscript; available in PMC 2016 January 04.
Davies et al.
Page 12
Table 2
Author Manuscript
Univariable Analysis of Surgical Outcomes in the Laparoscopic and Open Adhesiolysis Groups* Outcome OR time (minutes) ICU admission LOS (days) Superficial SSI < 30 days Deep SSI < 30 days Organ space SSI < 30 days Seroma < 30 days
t
Open (n = 64)
P Value
93 (65–123)
110.5 (62.0–187.5)
0.1096
2 (5.3%)
14 (21.9%)
0.0257
3.5 (2.0–6.0)
9 (5–15)
30 days
4 (10.5%)
10 (15.6%)
0.4694
Deep SSI > 30 days
1 (2.6%)
5 (7.8%)
0.4073
0 (0%)
4 (6.3%)
0.2939
1 (2.6%)
0 (0%)
0.3725
0 (0%)
1 (1.6%)
1.0000
Readmission
8 (21.1%)
19 (29.7%)
0.3392
Reoperation
6 (15.8%)
14 (21.9%)
0.4542
0 (0%)
3 (4.7%)
0.2918
Organ space SSI > 30 days Seroma > 30 days Hematoma > 30 days
30-day mortality *
Categorical data reported as number (%); χ2 or Fisher’s exact test was used depending on the size of the data for each respective variable (i.e., if any one cell in a 2 × 2 table was less than 5, Fisher’s exact test was used). Continuous data reported as either mean ± standard deviation or median (first quartile, third quartile) depending on the normalcy of distribution; Student’s t test or Wilcoxon rank sum was used depending on the normalcy of distribution. OR, operating room; ICU, intensive care unit; LOS, postoperative hospital length of stay; SSI, surgical site infection.
Author Manuscript Author Manuscript Am Surg. Author manuscript; available in PMC 2016 January 04.
Davies et al.
Page 13
Table 3
Author Manuscript
Univariable Analysis of Surgical Outcomes in Patients with Perioperative Contamination* Outcome OR time (minutes)
No Perioperative Contamination (n = 58)
Perioperative Contamination (n = 44)
P Value
72 (46–116)
135.5 (101.5–190.5)
30 days
1 (1.7%)
5 (11.4%)
0.0821
Organ space SSI > 30 days
1 (1.7%)
3 (6.8%)
0.3125
Seroma > 30 days
1 (1.7%)
0 (0%)
1.0000
0 (0%)
1 (2.3%)
0.4314
Readmission
11 (19.0%)
16 (36.4%)
0.0485
Reoperation
6 (10.3%)
14 (31.8%)
0.0068
30-day mortality
2 (3.5%)
1 (2.3%)
1.0000
Hematoma > 30 days
*
Categorical data reported as number (%); χ2 or Fisher’s exact test was used depending on the size of the data for each respective variable (i.e., if any one cell in a 2 × 2 table was less than 5, Fisher’s exact test was used). Continuous data reported as either mean ± standard deviation or median (first quartile, third quartile) depending on the normalcy of distribution; Student’s t test or Wilcoxon rank sum was used depending on the normalcy of distribution. OR, operating room; ICU, intensive care unit; LOS, postoperative hospital length of stay; SSI, surgical site infection.
Author Manuscript Author Manuscript Am Surg. Author manuscript; available in PMC 2016 January 04.
Davies et al.
Page 14
Table 4
Author Manuscript
Univariable Analysis of Surgical Outcomes in Patients with High-grade Bowel Obstructions as Compared with Partial Small Bowel Obstruction* Outcome OR time (minutes) ICU admission LOS (days)
PSBO (n = 54)
HGBO (n = 25)
P Value
107(65–145)
95(51–156)
0.4244
8 (14.8%)
7 (28%)
0.2186
6 (3–14)
9 (5–13)
0.3013
15 (27.8%)
5 (20%)
0.4596
Deep SSI < 30 days
5 (9.3%)
0 (0%)
0.1730
Organ space SSI < 30 days
3 (5.6%)
0 (0%)
0.5476
Seroma < 30 days
1 (1.9%)
2 (8%)
0.2339
Hematoma < 30 days
3 (5.6%)
0 (0%)
0.5476
Superficial SSI > 30 days
9 (16.7%)
4 (16%)
1.0000
Deep SSI > 30 days
4 (7.4%)
1 (4%)
1.0000
Organ space SSI > 30 days
2 (3.7%)
0 (0%)
1.0000
0 (0%)
1 (4%)
0.3165
Superficial SSI < 30 days
Author Manuscript
Seroma > 30 days Hematoma > 30 days
1 (1.9%)
0 (0%)
1.0000
Readmission
14 (25.9%)
4 (16%)
0.3280
Reoperation
8 (14.8%)
4 (16%)
1.0000
30-day mortality
1 (1.9%)
0 (0%)
1.0000
*
Categorical data reported as number (%); χ2 or Fisher’s exact test was used depending on the size of the data for each respective variable (i.e., if any one cell in a 2 × 2 table was less than 5, Fisher’s exact test was used). Continuous data reported as either mean ± standard deviation or median (first quartile, third quartile) depending on the normalcy of distribution; Student’s t test or Wilcoxon rank sum was used depending upon the normalcy of distribution.
Author Manuscript
PSBO, partial small bowel obstruction; HGBO, high-grade bowel obstruction; OR, operating room; ICU, intensive care unit; LOS, postoperative hospital length of stay; SSI, surgical site infection.
Author Manuscript Am Surg. Author manuscript; available in PMC 2016 January 04.
Davies et al.
Page 15
Table 5
Author Manuscript
Univariable Analysis of Surgical Outcomes in Patients Managed Conservatively (followed by surgery) as Compared with Patients Managed Electively* Outcome
Elective (n = 13)
Conservative (n = 54)
P Value
OR time (minutes)
104(72.5–161.5)
104.5(61–158)
0.8167
1 (7.7%)
10 (18.5%)
0.6772
ICU admission LOS (days)
2 (0–5)
9 (5–17)
