Who Should Manage Patients with Adhesive Small Bowel Obstruction?

External validation of a CT score for predicting ischaemia in adhesive small-bowel obstruction

OBJECTIVES

To assess the diagnostic accuracy, in a validation cohort, of a score based on three CT items, which has shown good performance for predicting ischaemia complicating acute adhesive small-bowel obstruction (SBO).

METHODS

This retrospective single-centre study of diagnostic accuracy included consecutive patients admitted for acute adhesive SBO in 2015-2022, who were treated conservatively or underwent surgery within 24 h after CT. The gold standard for ischaemia was an intraoperative diagnosis for operated patients, while the absence of ischaemia was confirmed either by its absence during surgery or by clinical follow-up in patients who did not undergo surgery. Three radiologists independently assessed the three score items, namely, decreased bowel-wall enhancement, diffuse mesenteric haziness, and closed-loop mechanism. Inter-observer agreement was evaluated by computing Fleiss' kappa. The diagnostic performance characteristics of the score were computed.

RESULTS

Of the 164 patients analysed (median age, 70 [57-80] years; 88 [54%] males), 57 (34.8%) had surgery, including 41 (71.9%) with intra-operative evidence of bowel ischaemia, whereas 107 (65.2%) were treated conservatively. A score ≥ 2/3 had a sensitivity of 78% (95% CI: 62-89%), a specificity of 97% (95% CI: 92-99%), a positive predictive value of 89% (95% CI: 74-97%), and a positive likelihood ratio of 24 (95% CI: 9.03-63.79). Adding increased unenhanced bowel-wall attenuation and requiring ≥ 2/4 items did not improve score performance. Fleiss' kappa values indicated moderate to substantial agreement between observers: 0.64 [0.56-0.73] for decreased bowel-wall enhancement, 0.57 [0.48-0.66] for diffuse mesenteric haziness, and 0.68 [0.59-0.76] for closed-loop mechanism.

CONCLUSIONS

The results of this external validation study support the reproducibility and good diagnostic performance of the score based on three CT items for predicting bowel ischaemia complicating acute adhesive SBO.

KEY POINTS

Question The Millet score with three enhanced CT items for predicting bowel ischaemia complicating acute adhesive SBO has not been assessed in an external validation cohort. Findings Adding "increased unenhanced bowel-wall attenuation" to the "decreased bowel-wall enhancement", "diffuse mesenteric haziness", and "closed-loop mechanism" items did not improve score performance. Clinical relevance In an external validation cohort, a score based on three CT items performed well for predicting ischaemia in patients with acute adhesive SBO and showed acceptable inter-observer agreement. This score may help identify patients for surgery.

Utility of Abbreviated Small Bowel Follow Through Study in the Management of Small Bowel Obstruction

INTRODUCTION

Small bowel obstruction is a common surgical complaint. Most small bowel obstructions are managed successfully nonoperatively. Unanimous guidelines for nonoperative management of small bowel obstruction do not exist.

METHODS

A standardized protocol for water-soluble contrast administration and abbreviated small bowel follow through imaging was implemented in January of 2021. A retrospective chart review identified 111 patients admitted for SBO from 6/2019 to 9/2019 for a control group. A planned follow-up review identified 158 patients managed according to the new protocol from 3/2021 to 10/2021. The primary outcome was in-hospital length of stay. Standard statistical analyses were performed and pre-specified.

RESULTS

Before implementation of the standardized protocol patients that were managed strictly nonoperatively, the mean length of stay (LOS) was 8.3 days. After implementation, the average LOS was 4.8 (P < .0001). Comparatively, patients admitted after protocol implementation were more likely to undergo CT scan with PO contrast on admission (98.1% vs 90.1%; P < .005), undergo NG tube decompression (84.7% vs 68.5%; P < .005), and undergo water-soluble contrast with abbreviated or formal SBFT (75.3% vs 37.8%; P < .0001).

CONCLUSION

Implementation of a standardized protocol utilizing abbreviated SBFT with water-soluble contrast for the management of SBO at our institution resulted in a decrease in the average length of stay for patients definitively managed in a nonoperative fashion.

Diseño y validación de una herramienta para la predicción de desenlaces adversos en pacientes con obstrucción intestinal por bridas: La escala HALVIC

Introducción. La obstrucción intestinal por bridas representa una causa común de consulta a los servicios de urgencias, pero hay poca claridad sobre qué pacientes tienen mayor riesgo de desarrollar complicaciones. El objetivo de este estudio fue diseñar y validar una escala de predicción de riesgo de desenlaces adversos en pacientes con obstrucción intestinal por bridas. Métodos. Estudio de cohorte retrospectivo realizado a partir de la base de datos MIMIC-IV. Se incluyeron pacientes adultos admitidos al servicio de urgencias entre 2008 y 2019, con diagnóstico de obstrucción intestinal por bridas. El desenlace principal fue el compuesto de resección intestinal, ingreso a unidad de cuidados intensivos y mortalidad por cualquier causa. Se diseñó una escala de predicción de riesgo asignando un puntaje a cada variable. Resultados. Se incluyeron 513 pacientes, 63,7 % hombres. El desenlace compuesto se presentó en el 25,7 % de los casos. La edad, historia de insuficiencia cardiaca y enfermedad arterial periférica, nivel de hemoglobina, recuento de leucocitos e INR constituyeron el mejor modelo de predicción de estos desenlaces (AUC 0,75). A partir de este modelo, se creó la escala simplificada HALVIC, clasificando el riesgo del desenlace compuesto en bajo (0-2 puntos), medio (3-4 puntos) y alto (5-7 puntos). Conclusión. La escala HALVIC es una herramienta de predicción simple y fácilmente aplicable. Puede identificar de manera precisa los pacientes con obstrucción intestinal por bridas con alto riesgo de complicaciones, permitiendo el ajuste individualizado de las estrategias de manejo para mejorar los desenlaces.

Should Surgical Services Admit Small Bowel Obstructions Managed Non-operatively?

INTRODUCTION

Over the past decade, small bowel obstructions (SBO) have been increasingly managed non-operatively. Prior studies have looked at outcomes based on admission to surgical services (SS) or medicine services (MS), but most are restricted to operative patients. This study evaluates the outcomes of non-operative patients specifically.

METHODS

A 12-year retrospective cohort study of patients ≥18-years-old admitted with SBO within one healthcare system was performed. Only non-operative patients were included. Clinicodemographic characteristics and admission details were extracted from the electronic medical record. Statistical analysis was performed using the student's t-test, chi-square, and multivariable regression.

RESULTS

A total of 3278 patients were included, of which 933(28.4%) patients were admitted to a SS. MS patients were older (57.7 vs 54.7 years, P < .001) and more likely to have diabetes (24.1 vs 20.2%, P = .015), CHF (5.7 vs 3.1%, P = .002), and AKI (29.8 vs 16.7%, P < .001). SS patients were more likely to have cancer (19.3 vs 13.7%, P < .001). Univariate analysis showed admission to SS decreased length of stay (3.4 vs 4.1 days, P < .001) and index admission mortality (0.1 vs 2.2%, P < .001). On multivariable analysis, admission to a SS decreased admission mortality (OR 0.056), 30-day mortality (OR 0.15), and 180-day mortality (OR 0.307). Similarly, 30-day readmissions (OR 0.683) and 180-day readmission (OR 0.54) were also significantly decreased. Length of stay was decreased by .6 days (P < .001).

DISCUSSION

In patients with non-operative SBO, admission to a surgical service decreased length of stay, mortality, and readmission. Further work should be completed evaluating how increased comorbidities affect long term outcomes. However, significantly decreased length of stay and mortality continue to support surgical services admitting SBO patients.

[Nasointestinal intubation in the treatment of acute adhesive small bowel obstruction]

Proximal gastrointestinal decompression is essential in the treatment of acute adhesive small bowel obstruction. Improvement of endoscopic methods, surgical instruments and radiological methods of control makes it possible to timely assess lavage and intra-intestinal therapy. The review presents current views on upper gastrointestinal decompression and other options for the treatment of adhesive small bowel obstruction.

Admitting Service and Outcome for Small Bowel Obstruction

INTRODUCTION

Small bowel obstruction (SBO) is a common admission diagnosis. Prior research has shown improved length of stay and time to operation for SBO patients on surgical services (SS) compared to medical services (MS). This study evaluates the impact of admitting service on readmission and mortality.

METHODS

A 12-year retrospective cohort study of patients ≥18 years old, admitted with SBO to either a MS or SS within one health care system was performed. Clinicodemographic characteristics and admission details were extracted and reviewed. Statistical analyses performed included the Student's t-test, chi-square, and multivariable regression.

RESULTS

The study included 7921 patients, of which 3862 (48.8%) were admitted to a SS. No significant clinicodemographic differences existed between the groups except SS patients were more likely to have cancer (23.3% vs 15.2%, P < .0001) and to be within a 30-day post-operative period (9.4% vs 1.8%, P < .0001). On multivariable analysis, admission to a SS was associated with a decreased admission mortality (OR .70), 30-day mortality (OR .42), and 180-day mortality (OR .42). 30-day readmissions (OR .54) and 180-day readmission (OR .43) were also significantly decreased for SS patients. In patients requiring a procedure during admission, there was significantly decreased admission mortality (OR .684), 30-day mortality (OR .470), 180-day mortality (OR .431), 30-day readmission (OR .63), and 180-day readmission (OR .50).

CONCLUSION

In patients with SBO, admission to a SS confers decreased odds of readmission and mortality compared to MS. Future studies are needed to understand the management decisions potentially underlying these differences. These findings may help better define admission pathways and improve outcomes.

Emergency Medicine Evaluation and Management of Small Bowel Obstruction: Evidence-Based Recommendations

BACKGROUND

Small bowel obstruction (SBO) is a commonly diagnosed disease in the emergency department (ED). Recent literature has evaluated the ED investigation and management of SBO.

OBJECTIVE

This review evaluates the ED investigation and management of adult SBO based on the current literature.

DISCUSSION

SBO is most commonly due to occlusion of the small intestine, resulting in fluid and gas accumulation. This may progress to mucosal ischemia, necrosis, and perforation. A variety of etiologies are present, but in adults, adhesions are the most common cause. Several classification systems are present. However, the most important distinction is complete vs. partial and complicated vs. simple obstruction, as complete complicated SBO more commonly requires surgical intervention. History and physical examination can vary, but the most reliable findings include prior abdominal surgery, history of constipation, abdominal distension, and abnormal bowel sounds. Signs of strangulation include fever, hypotension, diffuse abdominal pain, peritonitis, and several others. Diagnosis typically requires imaging, and though plain radiographs are often ordered, they cannot exclude the diagnosis. Computed tomography and ultrasound are reliable diagnostic methods. Management includes intravenous fluid resuscitation, analgesia, and determining need for operative vs. nonoperative therapy. Nasogastric tube is useful for patients with significant distension and vomiting by removing contents proximal to the site of obstruction. Surgery is needed for strangulation and those that fail nonoperative therapy. Surgical service evaluation and admission are recommended.

CONCLUSION

SBO is a common reason for admission from the ED. Knowledge of recent literature can optimize diagnosis and management.