Clinical Effect of Water-Soluble Contrast Agents for Small Bowel Obstruction in the Virgin Abdomen

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.

Small Bowel Obstruction in Virgin Abdomen: Predictors of Surgical Intervention Need in Resource-Limited Setting

Background

Limited evidence is available regarding the management of small bowel obstruction in the virgin abdomen (SBO-VA), with most studies excluding this entity. This study aims to assess the available data on the treatment outcomes and predictors of surgical intervention in SBO-VA.

Methods

A retrospective cross-sectional study was conducted between 2015 and 2021, including all diagnosed and managed cases of SBO-VA at Al-Nasar Hospital. Patients were divided according to the treatment approach into surgical or conservative groups. Preoperative laboratory and radiologic data were gathered and compared between groups.

Results

During the study period, 67 cases, primarily males (58.2%), with an average age of 52.2±14.4 years were assessed. Common comorbidities included diabetes (20.9%) and hypertension (16.4%). Key symptoms were rebound tenderness (82.1%) and abdominal tenderness (70.1%). The predominant etiology was adhesions (23.9%). About 46.2% received conservative treatment, 53.8% underwent urgent surgery. Conservative treatment failed in 9.4% of cases, and complications arose in 23.9%, with most being fever (17.9%). Factors necessitating surgical management included older age (58.8 ±11.7 vs 44.9 ±13.8 years, p<0.001), previous hospital admission (p<0.001), presence of abdominal tenderness (p=0.030), longer abdominal pain duration (4.0 ±0.9 vs 2.1 ±0.6 days, p<0.001), higher C- reactive protein (p= 0.033), higher white blood cell (p= 0.006), longer time to hospital presentation (75.3 ±17.2 vs 39.0 ±22.8 days, p= <0.001), small bowel thickness ≥3 cm (p=0.009), and reduced bowel enhancement (p <0.001) on computed tomography imaging. In surgical group, the need for ICU admission was higher and hospital stays were shorter than in conservative group and were statistically significant (p<0.05).

Conclusion

The main etiology of SBO-VA in our study was adhesions. Older age, previous hospital admission, longer abdominal pain duration, abdominal tenderness, increased inflammatory markers, and alarm signs on CT scans are the main factors for determining the need for urgent surgical exploration in patients with SBO-VA. To achieve prompt identification and intervention, it is crucial to maintain a high level of vigilance and awareness, even in individuals with no prior surgical history.

Management of adhesive small bowel obstruction: the results of a large retrospective study

BACKGROUND

Postoperative adhesive small bowel obstruction (SBO) is a frequent cause of hospital admission in a surgical department. Emergency surgery is needed in a majority of patients with bowel ischemia or peritonitis; most adhesive SBO can be managed nonoperatively. Many studies have investigated benefits of using oral water-soluble contrast to manage adhesive SBO. Treatment recommendations are still controversial.

METHODS

We conducted an observational retrospective monocentric study to test our protocol of management of SBO using Gastrografin®, enrolling 661 patients from January 2008 to December 2021. An emergency surgery was performed in patients with abdominal tenderness, peritonitis, hemodynamic instability, major acute abdominal pain despite gastric decompression, or CT scan findings of small bowel ischemia. Nonoperative management was proposed to patients who did not need emergency surgery. A gastric decompression with a nasogastric tube was immediately performed in the emergency room for four hours, then the nasogastric tube was clamped and 100 ml of nondiluted oral Gastrografin® was administered. The nasogastric tube remained clamped for eight hours and an abdominal plain radiograph was taken after that period. Emergency surgery was then performed in patients who had persistent abdominal pain, onset of abdominal tenderness or vomiting during the clamping test, or if the abdominal plain radiograph did not show contrast product in the colon or the rectum. In other cases, the nasogastric tube was removed and a progressive refeeding was introduced, starting with liquid diet.

RESULTS

Seventy-eight percent of patients with SBO were managed nonoperatively, including 183 (36.0%) who finally required surgery. Delayed surgery showed a complete small bowel obstruction in all patients who failed the conservative treatment, and a small bowel resection was necessary in 19 patients (10.0%): among them, only 5 had intestinal ischemia.

CONCLUSIONS

Our protocol is safe, and it is a valuable strategy in order to accelerate the decision-making process for management of adhesive SBO, with a percentage of risk of late small bowel resection for ischemia esteemed at 0.9%.

Small Bowel Obstruction in Patients without Prior Abdominal Surgery: To Operate or Not?

INTRODUCTION

Surgical exploration is still considered mandatory in the setting of small bowel obstruction (SBO) in patients without prior intra-abdominal surgery. However, recent studies have challenged this 'classic' approach describing success with conservative non-surgical treatment. The aim of this study is to identify clinical, radiological and biochemical variables that may be associated with the absence of intra-abdominal pathology in patients with SBO who have not undergone previous surgery.

METHODS

This is a retrospective cohort study of prospectively recorded data. Patients with SBO without prior abdominal surgery who presented to a single tertiary referral medical center between 2009 and 2019 were included.

RESULTS

Eighty-seven patients were included of whom 61(70.0%) were allocated to the 'therapeutic exploration' group and 26 (30.0%) to the 'non-therapeutic exploration' group. Forty-eight patients (55.0%) had adhesions, 17.2% had closed-loop obstruction, 10.0% had an internal hernia, 27.6% had bowel ischemia and 5.7% had bowel necrosis. Although multiple clinical, laboratory, radiological and preoperative factors were examined, none were significantly associated with pathological findings during surgical exploration. There was no statistically significant difference in the incidence of complications when comparing between those groups.

CONCLUSIONS

In this series, no variables were associated with intra-abdominal pathology in patients who underwent surgery for SBO with no history of prior abdominal surgery. However, the fact that 27.0% had ischemic bowel upon surgical exploration suggests that this approach is still mandatory for this specific group of patients. Furthermore, clinicians and patients should be aware that negative exploration may be expected in up to 30.0%.

Clinical impact of laparoscopic surgery and adhesion prevention material for prevention of small bowel obstruction

Aim

Adhesive small bowel obstructions (SBO) are one of the most common complications following abdominal surgery, and they decrease patient quality of life. Since 2000, laparoscopic surgery has been employed with increasing frequency, as has adhesion prevention material (APM). In this study we tried to evaluate whether laparoscopic surgery and APM reduce the incidence of SBO.

Methods

In Cohort 1, we included patients who developed SBO and received inpatient treatment between 2015 and 2018. We evaluated the elapsed time between precedent surgery and the onset of SBO, and what kind of surgery most often causes SBO. In Cohort 2, we included patients who underwent digestive surgery between 2012 and 2014 and evaluated SBO incidence within 5 y after the precedent surgery.

Results

In all, 2058 patients were included in Cohort 1. Of these, 164 had experienced no precedent surgery. Among patients with a history of abdominal surgery, 29.7% experienced SBO within 1 y after the precedent surgery and 48.1% within 3 y. Altogether, 18798 patients were analyzed in Cohort 2. The incidence of SBO after laparoscopic colorectal surgery was lower than that of open colorectal surgery (P < .001), and laparoscopic gastroduodenal surgery was also lower (P = .02). However, there were no differences between laparoscopic and open surgery for other types of surgery. The use of APM had no effect on SBO incidence in any type of abdominal surgery.

Conclusions

Laparoscopic surgery helps to reduce SBO incidence only in colorectal surgery, and possibly in gastroduodenal surgery. APM does not reduce SBO after abdominal surgery.

Diagnosis and management of small bowel obstruction in virgin abdomen: a WSES position paper

Background

Small bowel obstruction (SBO) is a common surgical emergency, causing high morbidity and healthcare costs. The majority of SBOs are caused by adhesions that result from previous surgeries. Bowel obstruction, however, also occurs in patients without previous operation or known pathology, a so called virgin abdomen. It is unknown if small bowel obstruction in the virgin abdomen (SBO-VA) can be managed according to the same principles as other cases of small bowel obstruction. The aim of this position paper is to evaluate the available evidence on etiology and management of small bowel obstruction in the virgin abdomen.

Methods

This is a narrative review with scoping aspects. Clinical topics covered in this review include epidemiology and etiology of SBO-VA, diagnosis and imaging, initial assessment, the role of surgical management in SBO-VA, and the role of non-operative management in SBO-VA.

Results

Our scoping search revealed seven original studies reporting original patient data related to SBO-VA. All the included studies are retrospective cohorts, with populations ranging between 44 and 103 patients with SBO-VA. Adhesions were found to be the cause of the obstruction in approximately half of the reported cases of SBO-VA. A relatively high number of cases of SBO-VA were managed surgically with studies reporting 39–83%. However, in cases where a trial of non-operative management was started, this was generally successful.

Conclusion

The data available suggest that etiology and treatment results for patients with SBO-VA are largely comparable to the results in patients with SBO after previous abdominal surgery. We therefore propose that patients with a virgin abdomen could be treated according to existing guidelines for SBO and adhesive small bowel obstruction.

Non-operative Management of Small Bowel Obstruction in Patients with No Previous Abdominal Surgery: A Systematic Review and Meta-analysis

While the contemporary management of adhesive small bowel obstruction (SBO) often includes a trial of non-operative management (NOM), surgical dogma dictates urgent operative exploration in patients without previous abdominal surgery. This dogma has been challenged by recent evidence suggesting most obstructions in this population are adhesive in nature. The objectives of this review were to evaluate the feasibility of NOM in patients with SBO and no history of previous abdominal surgery, to examine the etiologies of SBO in this population, and to explore the rate of adverse events seen following NOM. Embase, Medline, Cochrane, and Google Scholar were searched from inception to September 24, 2019. Articles reporting on NOM for SBO in patients without previous abdominal surgery and without clinical or radiographic features necessitating an emergent operation were included. Data were combined to obtain a pooled proportion of patients discharged without operation following a trial of NOM. 6 studies reporting on a total of 272 patients were included. The pooled proportion of patients discharged following NOM was 49.5% (95% CI 23.7-75.3%). Adhesions were found to be the predominant cause of obstruction. NOM did not appear to increase short-term complications. Most SBOs in patients without previous abdominal surgery are adhesive in nature and many patients can be discharged from hospital without surgery. While the short-term outcomes of NOM are acceptable, future studies are needed to address the long-term outcomes and safety of NOM as a treatment strategy for SBO in patients without previous abdominal surgery.

Non-operative management of small bowel obstruction in virgin abdomen: a systematic review

The aim of this study was to systematically review the feasibility and safety of non-operative management of small bowel obstruction (SBO) in virgin abdomen. A systematic review was performed through December 2019. The primary outcome was the resolution of non-operative management of SBO in virgin abdomen. Secondary outcomes were the etiology of SBO and findings of exploratory laparotomy. Six studies were included in the analysis. Of the 442 patients, 2 with metastatic cancer received palliative care, and the management in 26 was not reported, so these patients were excluded. A total of 414 patients were ultimately analyzed, including 203 patients (49%) who were managed non-operatively and 211 (51%) who underwent surgical management. Of the 203 managed non-operatively, the condition of 194 (96%) was resolved without further intervention. The remaining 9 (5%) patients failed non-operative management and ultimately required surgery. Of the 211 patients who underwent surgical exploration, only 137 had their intraoperative findings reported. Adhesions (n = 67; 49%) were the main cause, followed by malignancy (n = 14; 10%) and others (n = 33; 24%). No cause was found in 23 patients (17%). In highly select cases of SBO with virgin abdomen, non-operative management can be attempted if patients are clinically stable and computed tomography does not demonstrate concerning features or obvious pathology. Further well-designed prospective studies will be required prior to the introduction of this concept in clinical practice, as current evidence remains heterogeneous.

Successful use of water-soluble contrast in patients with small bowel obstruction and virgin abdomen: A case report

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Trial of nonoperative management is standard of care for adhesive SBO.

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Prior surgery is the most common cause of adhesions.

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Management of SBO in patients without prior surgery is a challenge.

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This is a case of SBO in a virgin abdomen patient successfully managed nonoperatively.

Introduction and importance

Nonoperative management of adhesive SBO is well established but remains a challenge in patients without prior abdominal surgery. We aim to report a case of successful nonoperative management with the use of enteral hypertonic water-soluble contrast administration in a patient with virgin abdomen.

Case presentation

A healthy 24-year old man with no previous surgery presented to the emergency room with one day of abdominal pain. A CT abdomen and pelvis was consistent with SBO without clear anatomic etiology. The patient refused surgical intervention, so we performed a trial of nonoperative management. On hospital day 2, a repeat CT A/P with enterally administered water-soluble contrast showed resolution of SBO. The patient has had no symptoms since hospital discharge on 6 months follow up.

Clinical discussion

Small bowel obstruction is most commonly secondary to adhesions from prior surgeries.

Even in patients with virgin abdomen, adhesions are the cause of SBO in 53%–73%.

Recent studies in patients with virgin abdomen showed that 92.1% that underwent nonoperative management did not have a recurrence of SBO with mean follow up of 4.5 years. The use of water-soluble contrast in patients with virgin abdomen was reported to have 92–97% success rate.

A meta-analysis showed a pooled prevalence of 7.7% of malignant etiology of SBO in these patients, more common with previous SBO admission or history of malignancy.

Conclusion

Nonoperative management with the therapeutic use of hypertonic water-soluble contrast is a viable treatment option in select cases and avoids the morbidity of surgical exploration.

Non-operative management for small bowel obstruction in a virgin abdomen: a systematic review

BACKGROUND

Small bowel obstruction (SBO) is a common general surgical presentation and there has been a shift towards non-operative management (NOM) for patients with previous abdominal surgery. Historically, exploratory surgery has been mandated for SBO in patients with a virgin abdomen. However, there is increasing evidence for NOM in this group of patients.

METHODS

A systematic review was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A search was undertaken between 1995 and 2020 on Ovid MEDLINE, EMBASE and PubMed. Primary outcome measures were success and failure rates, whereas secondary outcome measures were morbidity, mortality rates and identifying underlying aetiologies.

RESULTS

Six observational studies were included, with 205 patients in the NOM and 211 patients in the operative group. There was a high success rate of 95.6% and low morbidity rate of 3.1% in the NOM group compared to 88.6% and 26% in the operative group, respectively. Both groups reported no mortalities. The most common aetiologies for SBO in a virgin abdomen were adhesions (63%), malignancy (11%), foreign body/bezoar (5%), internal hernia (4%) and volvulus (4%).

CONCLUSION

NOM for SBO is a safe and feasible option for a select group of clinically stable patients with a virgin abdomen without features of closed-loop obstruction. Adhesions are the most common cause of SBO in this group of patients. Further large-scale prospective clinical studies with standardized NOM modality, homogenous clinical resolution indicators and long-term follow-up data are warranted to allow for quantitative analysis to reinforce this evidence.