Long-term outcomes of gastrografin in small bowel obstruction

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.

Current Management of Adhesive Small Bowel Obstructions in Children

Adhesive small bowel obstructions are a common cause of morbidity in children who underwent prior abdominal surgery. The concept of partial versus complete bowel obstruction is outdated and lacks precision to be clinically useful. Identifying patients with indications for immediate operative intervention is critical and must be recognized to limit morbidity. Clinical protocols and contrast challenge algorithms have attempted to identify patients that will resolve their bowel obstruction nonoperatively; there has been slow uptake in the pediatric patient population versus adults until recently. Incorporating predictive models and standardized contrast challenge protocols will help reduce interpractitioner variability and improve clinical outcomes.

Prognostic Value of Water-Soluble Contrast Challenge for Nonadhesive Small Bowel Obstruction

BACKGROUND

There is little evidence supporting the use of a water-soluble contrast challenge (WSCC) for conservative management of nonadhesive small bowel obstruction (NASBO). Our objective was to evaluate the prognostic value of the WSCC in a diverse group of patients with NASBO in comparison with patients with adhesive small bowel obstruction (ASBO).

STUDY DESIGN

Retrospective chart review of patients with ASBO or NASBO who underwent a WSCC during a 4-year time period was performed. The primary study endpoint was any intervention for small bowel obstruction during the initial admission or within 30 days of discharge.

RESULTS

A total of 106 patients were included, 53 with ASBO (mean age 64 ± 13 years [SD]; 55% women) and 53 with NASBO (mean age 59 ± 13 years [SD]; 57% women). A higher rate of interventions during admission or within 30 days of discharge was seen in patients with NASBO compared with ASBO (24/53 [45%] vs 12/53 [23%]; p = 0.01), including those with colonic transit times of less than 36 hours (14/41 [34%] vs 5/43 [12%]; p = 0.01). Using multivariate analysis, transit time greater than 36 hours remained an independent predictor of an intervention during admission or within 30 days of discharge (p < 0.001, odds ratio 19.0), after controlling for the type of small bowel obstruction.

CONCLUSIONS

A majority of patients with NASBO were successfully managed conservatively during a 30-day period, supporting the use of WSCC in patients with NASBO; however, patients with NASBO had a higher rate of interventions during admission or within 30 days of discharge.

Evaluating suspected small bowel obstruction with the water-soluble contrast challenge

With optimized technique, the water-soluble contrast challenge is effective at triaging patients for operative vs non-operative management of suspected small bowel obstruction. Standardized study structure and interpretation guidelines aid in clinical efficacy and ease of use. Many tips and tricks exist regarding technique and interpretation, and their understanding may assist the interpreting radiologist. In the future, a CT-based water-soluble contrast challenge, utilizing oral contrast given as part of the initial CT examination, might allow for a more streamlined algorithm and provide more rapid results.

Outcomes of a low-osmolar water-soluble contrast pathway in small bowel obstruction

BACKGROUND

Adhesive small-bowel obstruction (SBO) is a common surgical condition accounting for a significant proportion of acute surgical admissions and surgeries. The implementation of a high-osmolar water-soluble contrast challenge has repeatedly been shown to reduce hospital length of stay and possibly the need for surgery in SBO patients. The effect of low-osmolar water-soluble contrast challenge however, is unclear. The aim of this study is to evaluate the outcomes of an SBO pathway including a low-osmolar water-soluble contrast challenge.

METHODS

A prospective cohort of patients admitted for SBO were placed on an evidence-based SBO pathway including low-osmolar water-soluble contrast between January 2017 and October 2018 and were compared with a historical cohort of patients prior to the implementation of the pathway from September 2013 through December 2014. The primary outcome was length of stay less than 4 days with a secondary outcome of failure of nonoperative management.

RESULTS

There were 140 patients enrolled in the SBO pathway during the study period and 101 historic controls. The SBO pathway was independently associated with a length of stay less than 4 days (odds ratio, 1.76; 95% confidence interval, 1.03-3.00). Median length of stay for patients that were successfully managed nonoperatively was lower in the SBO pathway cohort compared with controls (3 days vs. 4 days, p = 0.04). Rates of readmission, surgery, and bowel resection were not significantly different between the two cohorts.

CONCLUSION

Implementation of an SBO pathway using a low-osmolarity contrast is associated with decreased hospital length of stay. Rates of readmission, surgery, and need for bowel resection for those undergoing surgery were unchanged. An SBO pathway utilizing low-osmolarity water-soluble contrast is safe and effective in reducing length of stay in the nonoperative management of adhesive small-bowel obstructions.

LEVEL OF EVIDENCE

Therapeutic study, level IV.

Small Bowel Obstruction

Identifying patients with small bowel obstruction who need operative intervention and those who will fail nonoperative management is a challenge. Without indications for urgent intervention, a computed tomography scan with/without intravenous contrast should be obtained to identify location, grade, and etiology of the obstruction. Most small bowel obstructions resolve with nonoperative management. Open and laparoscopic operative management are acceptable approaches. Malnutrition needs to be identified early and managed, especially if the patient is to undergo operative management. Confounding conditions include age greater than 65, post Roux-en-Y gastric bypass, inflammatory bowel disease, malignancy, virgin abdomen, pregnancy, hernia, and early postoperative state.

A Systematic Review of the Clinical Presentation, Diagnosis, and Treatment of Small Bowel Obstruction

PURPOSE OF REVIEW

This study aimed to systematically review small bowel obstruction (SBO), focusing on recent changes in diagnosis/therapy.

RECENT FINDINGS

SBO incidence is about 350,000/annum in the USA. Etiologies include adhesions (65%), hernias (10%), neoplasms (5%), Crohn's disease (5%), and other (15%). Bowel dilatation occurs proximal to obstruction primarily from swallowed air and secondarily from intraluminal fluid accumulation. Dilatation increases mural tension, decreases mucosal perfusion, causes bacterial proliferation, and decreases mural tensile strength that increases bowel perforation risks. Classical clinical tetrad is abdominal pain, nausea and emesis, abdominal distention, and constipation-to-obstipation. Physical exam may reveal restlessness, acute illness, and signs of dehydration and sepsis, including tachycardia, pyrexia, dry mucous membranes, hypotension/orthostasis, abdominal distention, and hypoactive bowel sounds. Severe direct tenderness, involuntary guarding, abdominal rigidity, and rebound tenderness suggest advanced SBO, as do marked leukocytosis, neutrophilia, bandemia, and lactic acidosis. Differential diagnosis includes postoperative ileus, narcotic bowel, colonic pseudo-obstruction, mesenteric ischemia, and large bowel obstruction. Medical resuscitation includes intravenous hydration, correcting electrolyte abnormalities, intravenous antibiotics, nil per os, and nasoenteral suction. Abdominal CT with oral and intravenous gastrografin contrast is highly sensitive and specific in detecting/characterizing SBO. SBO usually resolves with medical therapy but requires surgery, preferentially by laparoscopy, for unremitting total obstruction, bowel perforation, severe ischemia, or clinical deterioration with medical therapy. Overall mortality is 10% but increases to 30% with bowel necrosis/perforation. Key point in SBO is early diagnosis, emphasizing abdominal CT; aggressive medical therapy including rehydration, antibiotics, and nil per os; and surgery for failed medical therapy.