Early versus late adhesiolysis for adhesive-related intestinal obstruction: a nationwide analysis of inpatient outcomes

A systematic review of participant descriptors reported in studies of adhesive small bowel obstruction

AIM

Reporting of participant descriptors in studies of adhesive small bowel obstruction (ASBO) can help identify characteristics associated with favourable outcomes and allow comparison with other studies and real-world clinical populations. The aim was to identify the pattern of participant descriptors reported in studies assessing interventions for ASBO.

METHOD

This systematic review was registered with PROSPERO (CRD42021281031) and reported in line with the PRISMA checklist. Systematic searches of Ovid MEDLINE, Embase, and Cochrane Central Register of Controlled Trials (CENTRAL) were undertaken to identify studies assessing operative and non-operative interventions for adults with ASBO. Studies were dual screened for inclusion. Descriptors were categorised into conceptual domains by the research team.

RESULTS

Searches identified 2648 studies, of which 73 were included. A total of 156 unique descriptors were identified. On average, studies reported 12 descriptors. The most frequently reported descriptors were sex, age, SBO aetiology, history of abdominal surgery, BMI and ASA classification. The highest number of descriptors in a single study was 34, compared to the lowest number of descriptors which was one. Pathway factors were the least frequently described domain. Overall, 37 descriptors were reported in just one study.

CONCLUSION

There is a lack of consistency in participant descriptors reported in studies of SBO. Furthermore, a significant proportion of the descriptors were used infrequently. This makes it challenging to assess whether study participants are representative of the wider population. Further work is required to develop a Core Descriptor Set to standardise the reporting of patient characteristics and reduce heterogeneity between studies.

Modified frailty index predicts postoperative morbidity in adhesive small bowel obstruction: analyzing the National Inpatient Sample 2015-2019

BACKGROUND

There are limited data identifying predictors of postoperative outcomes in adhesive small bowel obstruction (ASBO). This study used the National Inpatient Sample (NIS) to assess the efficacy of the modified frailty index (mFI) to predict postoperative morbidity among patients undergoing an operation for ASBO.

METHODS

A retrospective analysis of the NIS between September 1, 2015, and December 31, 2019, was performed to identify adult patients who underwent nonelective operative intervention for ASBO. The mFI was used to stratify patients as either frail (mFI value ≥ 0.27) or robust (mFI value < 0.27). The primary outcomes were overall in-hospital postoperative morbidity and mortality. The secondary outcomes were system-specific morbidity, length of stay (LOS), total in-hospital healthcare cost, and discharge disposition. Univariable and multivariable regressions were used.

RESULTS

Overall, 23251 robust patients and 6122 frail patients were included. Adjusted analyses demonstrated that frail patients had increased in-hospital mortality (adjusted odds ratio [aOR], 2.16; 95% CI, 1.80-2.60), postoperative morbidity (aOR, 1.63; 95% CI, 1.52-1.74), postoperative LOS (adjusted mean difference [aMD], 0.97 days; 95% CI, 0.73-1.21), and total in-hospital healthcare costs (aMD, $18,921; 95% CI, $14,608-$23,235) and were less likely to be discharged home (aOR, 0.59; 95% CI, 0.55-0.63). The findings were unchanged on subgroup analysis of patients undergoing open operation and those older than 65 years of age.

CONCLUSION

The mFI may predict postoperative outcomes for ASBO. Stratifying patients based on frailty may assist clinicians and patients in making informed decisions, setting realistic expectations, and proactively planning postoperative disposition.

Clinical Indicators to Determine the Timing of Surgery for Adhesive Small Bowel Obstruction

BACKGROUND

Decompression of the intestine with a long tube or nasogastric tube is the first-choice treatment for adhesive small bowel obstruction (ASBO). Scheduling surgery while weighing the risks of surgery against conservative care is a crucial factor in clinical decision-making. Whenever feasible, unnecessary surgeries should be avoided, and it is essential to provide clinical markers for this. This study aimed to obtain evidence regarding the optimal timing of ASBO and when conservative treatment options are not successful.

METHODS

The data of patients diagnosed with ASBO and receiving long tube insertion for more than 7 days were reviewed. We investigated transit ileal drainage volume and recurrence. The primary outcomes were the change in the drainage volume from the long tube over time and the percentage of patients who required surgery. We evaluated some cutoff values to determine the indication for surgery based on the insertion duration and volume of long tube drainage.

RESULTS

Ninety-nine patients were enrolled in this study. Fifty-one patients showed improvement with conservative treatment, whereas 48 ultimately required surgery. When a daily drainage volume of ≥500 mL was considered an indication for surgery, 13-37 cases (25%-72%) would be judged unnecessary within 6 days of long tube insertion, while 5 cases (9.8%) would be judged unnecessary on day 7.

DISCUSSION

Unnecessary surgical interventions for ASBO might be avoided by assessing the drainage volume on day 7 after inserting a long tube.

Financial and Inpatient Burden of Adhesion-Related Small Bowel Obstruction: A Systematic Review of the Literature

BACKGROUND

Postoperative adhesions may occur after >90% of laparotomies and is the most common cause of small bowel obstruction (SBO). Despite the high incidence, there is a lack of data related to financial implications of adhesion-related SBO (ASBO). This systematic literature review of in-hospital costs for treatment of ASBO searched PubMed, Scopus and Google Scholar databases according to PRISMA guidelines. Exclusion criteria were reviews, editorials, clinical vignettes, studies of patients <18 years of age, studies with no English full text and studies assessing adhesiolysis for causes other than SBO or that used extrapolations with economic models. Main outcome measures were financial costs per patient and national costs.

RESULTS

Seven studies, published between 1999 and 2016, incorporating a total of 39 573 patients, were identified. Four were undertaken in European countries, one in the USA, 1 in New Zealand and 1 in Nigeria. Overall national costs regarding treatment of patients with ASBO ranged between $3.468 million and $1.77 billion. Median overall cost in the medical management group was $2371.5 ($1814-$2568) vs $12370 ($4914-$25321) in the surgical group. Median length of stay was 4 (3-7) days for patients conservatively treated and 11.5 (8-16.3) days for patients who underwent surgery. Median length of stay of operated patients on was almost triple that of patients conservatively managed.

CONCLUSIONS

Given the major financial implications of ASBO, further initiatives are needed to avoid operations for SBO when clinically appropriate and minimize delays taking patients with high suspicion of complete SBO to the operating room.

Diatrizoate (Gastrograffin®) Small Bowel Follow Through for Small Bowel Obstructions: Timing and Outcomes

INTRODUCTION

The advent of the Gastrograffin® small bowel follow through (G-SBFT) has resulted in a decreased rate of operative intervention of small bowel obstructions (SBO); however, there is no data to suggest when G-SBFT should be performed.

METHODS

We retrospectively reviewed 548 patients, admitted to 1 of 9 hospitals with a diagnosis of SBO. Patients were divided into two categories with regards to timing of G-SBFT: before (early) or after (late) 48 hours from admission. Primary outcomes were length of stay (LOS) and total cost. Secondary outcomes were operative interventions and mortality.

RESULTS

Of the reviewed patients, 71% had the G-SBFT ordered early. Comparing early versus late, there were no differences in patient characteristics with regards to age, sex, or BMI. There was a significant difference between LOS (4 vs 8 days, P < 0.05) and total cost ($17,056.19 vs $33,292.00, P < 0.05). There was no difference in mortality (1.3% vs 2.6%, P = 0.239) or 30-day readmission rates (15.6% vs 15.9%, P = 0.509). Patients in the early group underwent fewer operations (20.7% vs 31.9%, P = 0.05).

DISCUSSION

Patients that had a G-SBFT ordered early had a decreased LOS, total cost, and operative intervention. This suggests there is a benefit to ordering G-SBFT earlier in the hospital stay to reduce the overall disease burden, and that it is safe to do so with regards to mortality and readmissions. We therefore recommend ordering a G-SBFT within 48 hours to reduce LOS, cost, and need for an operation.

The Safety of Expectant Management for Adhesive Small Bowel Obstruction: A Systematic Review

BACKGROUND

Surgical training has long been to "never let the sun set on a bowel obstruction" without an operation to rule out and/or treat compromised bowel. However, advances in diagnostics have called into question the appropriate timing of non-emergent operations and expectant management is increasingly used. We performed a systematic review to evaluate the safety and effectiveness of expectant management for adhesive small bowel obstruction (aSBO) compared to early, non-emergent operation.

MATERIALS & METHODS

We queried PubMed, EMBASE, and Cochrane databases for studies (1990-present) comparing early, non-emergent operations and expectant management for aSBO (PROSPERO #CRD42017057676).

RESULTS

Of 4873 studies, 29 cohort studies were included for full-text review. Four studies directly compared early surgery with expectant management, but none excluded patients who underwent emergent operations from those having early non-emergent surgery, precluding a direct comparison of the two treatment types of interest. When aggregated, the rate of bowel resection was 29% in patients undergoing early operation vs. 10% in those undergoing expectant management. The rate of successful, non-operative management in the expectant group was 58%. There was a 1.3-day difference in LOS favoring expectant management (LOS 9.7 vs. 8.4 days), and the rate of death was 2% in both groups.

CONCLUSION

Despite the shift towards expectant management of aSBO, no published studies have yet compared early, non-emergent operation and expectant management. A major limitation in evaluating the outcomes of these approaches using existing studies is confounding by indication related to including patients with emergent indications for surgery on admission in the early operative group. A future study, randomizing patients to early non-emergent surgery or expectant management, should inform the comparative safety and value of these approaches.

A Significant Proportion of Small Bowel Obstructions Require >48 Hours to Resolve After Gastrografin

BACKGROUND

Gastrografin (GG)-based nonoperative approach is both diagnostic and therapeutic for partial small bowel obstruction (SBO). Absence of X-ray evidence of GG in the colon after 8 h is predictive of the need for operation, and a recent trial used 48 h to prompt operation. We hypothesize that a significant number of patients receiving the GG challenge require >48 h before an effect is seen.

METHODS

A post hoc analysis of an Eastern Association for the Surgery of Trauma multi-institutional SBO database was performed including only those receiving GG challenge. Successful nonoperative management (NOM) was defined as passage of flatus or nasogastric tube (NGT) removal. NOM was considered a failure if operative intervention was required. Multiple logistic regression was performed to identify predictors of delayed (>48 h) GG challenge effect and expressed as odds ratios with 95% confidence intervals.

RESULTS

Of 286 patients receiving GG, 208 patients (73%) were successfully managed nonoperatively. A total of 60 (29%) NOM patients had NGT decompression for >48 h (n = 54) or required >48 h to pass flatus (n = 34), with some requiring both (n = 28). Prior abdominal operations and SBO admission were protective of delayed GG effect (0.411 [0.169-1.00], P < 0.05; 0.478 [0.240-0.952], P < 0.036).

CONCLUSIONS

A significant proportion of patients at 48 h (29%) "failed" the GG challenge as they had yet to pass flatus or still required NGT but were nonetheless successfully managed nonoperatively. Extending the GG challenge beyond 48 h may help avoid unnecessary operations.

LEVEL OF EVIDENCE

Level II.

Managing Adhesive Small Bowel Obstruction with Water-Soluble Contrast Should Be Protocolized: A Retrospective Analysis

Aim  Current literature emphasizes the effectiveness of computed tomography (CT) and water-soluble contrast agent, Gastrografin, in the investigation of adhesive small bowel obstruction (ASBO). As there is no management protocol for ASBO at our institution, the aim of this study was to determine the effect of imaging methods—CT, Gastrografin challenge (GC), or plain-film X-ray—on patient outcomes in a clinical setting.

Methods  All 163 emergency presentations of ASBO during the study period between December 2010 and September 2012 were collected retrospectively. Cases were divided into three groups: CT with oral contrast, GC, or plain-film X-ray only. The primary outcome was time to theater.

Results  Patients investigated with X-ray only were significantly less likely to require surgery (6% in plain-film X-ray vs. 35% and 20% in CT and GC, respectively; p  = 0.003). In cases requiring surgery, GC was associated with a 24-hour longer time to imaging than CT ( p  < 0.001). The time to theater was 71:25 hours for GC versus 46:39 for CT ( p  = 0.039). There was no significant difference in bowel resection or complication rates.

Conclusion  Patients undergoing water-soluble contrast studies were subjected to unnecessary delays in their clinical course. These delays are costly and avoidable. The development and implementation of an evidence-based protocol for the management of small bowel obstruction is strongly recommended. The lack of a protocol likely caused significant delays in Gastrografin administration, reducing its known benefits for clinical decision-making and length of stay.

Surgeon attitudes and practice patterns in managing small bowel obstruction: a qualitative analysis

BACKGROUND

Historical training instructs surgeons to, "never let the sun set on a small bowel obstruction (SBO)" due to concern for bowel ischemia. However, the routine use of computed tomography scans for ruling out ischemia provides the opportunity for trial of nonoperative management, allowing time for resolution of adhesive SBO. In light of advances in practice, little is known about how surgeons manage these patients, in particular, whether there is consistency in the stated duration for safe nonoperative management.

METHODS

Using a case vignette (a patient with computed tomography scan diagnosed complete SBO without bowel ischemia), we interviewed a purposive sample of general surgeons practicing in Washington State to understand stated approaches to clinical management. Interview questions addressed typical practice, preferred timing of surgery, and approach. We conducted a content analysis to understand current practice and attitudes.

RESULTS

We interviewed 15 surgeons practicing across Washington State. Surgical practice patterns for patients with SBO varied widely. The period of time that surgeons were willing to manage patients nonoperatively ranged from 1-7 d. Interviews revealed insight into surgical decision-making, the importance of patient preferences, variation in practice, and evidence gaps. All surgeons acknowledged a lack of evidence to support appropriate management of patients with SBO.

CONCLUSIONS

Interviews with practicing surgeons highlight a changing paradigm away from routine early surgery for patients with adhesive SBO. However, there is lack of consensus in the appropriate duration of nonoperative management and practices vary considerably. These revealed attitudes inform the feasibility and design of future randomized studies of patients with adhesive SBO.

Outcomes After Surgery for Benign and Malignant Small Bowel Obstruction

BACKGROUND

Small bowel obstruction (SBO) is a common diagnosis; however, outcomes of and risk factors for SBO and malignant bowel obstruction (MBO) surgery are not well understood. We sought to characterize outcomes and risk factors for surgery for SBO and MBO.

METHODS

A retrospective cohort study was performed utilizing prospectively collected data from the Michigan Surgical Quality Collaborative (7/2012-3/2015). Cases included those with ICD9 diagnosis code of bowel obstruction and CPT codes for lysis of adhesions, intestinal bypass, and small bowel resection. Cases were stratified by disseminated malignancy (MBO). Factors associated with complications and 30-day mortality were evaluated.

RESULTS

Two thousand two hundred thirty-three patients underwent surgery for bowel obstruction, including 86 patients (3.9 %) with MBO. MBO patients had an adjusted mortality rate of 14.5 % (benign 5.0 %); the adjusted complication rate was 32.2 % (benign 27.0 %). Factors independently associated with mortality included disseminated cancer, older age, American Society of Anesthesiologists IV/V, cirrhosis, ascites, urinary tract infection, sepsis, albumin <3.5, hematocrit <30, and bowel resection.

CONCLUSIONS

Surgery for bowel obstruction carries a relatively high risk for morbidity and mortality, particularly in patients with malignant bowel obstruction. Considering the identified risk factors for mortality may help clinicians make recommendations regarding surgery in the setting of MBO.