Utilization of ultrasound for the evaluation of small bowel obstruction: A systematic review and meta-analysis

Gastrointestinal and Biliary Point-of-Care Ultrasound

Point-of-care ultrasound has been shown to have excellent diagnostic accuracy for a variety of gastrointestinal and biliary pathologies. This review explores the evidence and scanning techniques for hypertrophic pyloric stenosis, intussusception, appendicitis, small bowel obstruction, diverticulitis, hernias, pneumoperitoneum, and biliary pathology.

Optimal bowel diameter thresholds for diagnosing small bowel obstruction and surgical intervention with point-of-care ultrasound

OBJECTIVES

A bowel diameter threshold of ≥2.5 cm, originally derived from the research using computed tomography, is frequently used for diagnosing small bowel obstruction (SBO) with point-of-care ultrasound (POCUS). We sought to determine the optimal bowel diameter threshold for diagnosing SBO using POCUS and its accuracy in predicting surgical intervention.

METHODS

We conducted a secondary analysis using individual patient-level data from a previous systematic review on POCUS for SBO diagnosis across five academic EDs. Patient data were collected, including imaging results, surgical findings, and final diagnosis. The measured diameter of the small bowel using POCUS was recorded. ROC area under the receiver operating characteristic curves (AUC) were constructed to determine the optimal threshold for bowel diameter in predicting SBO diagnosis and surgical intervention. Subgroup analyses were performed based on sex and age.

RESULTS

A total of 403 patients had individual patient-level data available, with 367 patients included in the final analysis. The most accurate bowel diameter overall for predicting SBO was 2.75 cm (AUC = 0.76, 95% CI 0.71-0.81). A bowel diameter of ≤1.7 cm had 100% sensitivity with no miss rate, while a bowel diameter of ≥4 cm had 90.7% specificity in confirming SBO. Patients under 65 had an optimal threshold of 2.75 cm versus 2.95 cm in patients over 65. Females had an optimal threshold of 2.75 cm, while males had a value of 2.95 cm. There was no significant correlation between bowel diameter thresholds and surgical intervention.

CONCLUSION

A bowel diameter threshold of 2.75 cm on POCUS is more discriminative diagnostic accuracy for diagnosing SBO. Patients' age and sex may impact diagnostic accuracy, suggesting that tailored approaches may be needed.

A Novel Integrated Clinical-Biochemical-Radiological and Sonographic Classification of Necrotizing Enterocolitis

OBJECTIVE

 To evaluate the sensitivity and specificity of clinical, laboratory, and radiological markers and the neonatologist-performed intestinal ultrasound (NP-IUS) for treatment interventions in preterm neonates who developed necrotizing enterocolitis (NEC).

STUDY DESIGN

 This was a case-control study of preterm neonates < 35 weeks with a diagnostic workup for NEC. The diagnostic workup included NP-IUS performed by trained neonatologists using a standard protocol, abdominal roentgenogram (AXR), and laboratory investigations. Intestinal ultrasound (IUS) performed by two neonatologists was standardized to detect 11 injury markers. AXRs were read independently by experienced pediatric radiologists. The investigators who retrospectively interpreted the IUS were blinded to the clinical and treatment outcomes.

RESULTS

 A total of 111 neonates were assessed. Fifty-four did not require intervention and formed the control group. Twenty cases were treated medically, 21 cases were treated with late surgery for stricture or adhesions, and 16 were treated with early surgery. The integrated model of cumulative severity of ultrasound markers, respiratory and hemodynamic instability, abdominal wall cellulitis, and C- reactive protein > 16 mg/L had an area under the curve (AUC) of 0.89 (95% confidence interval [CI]: 0.83-0.94%, p < 0.0001) for diagnosing NEC requiring surgical intervention. We also investigated the utility of Bell's classification to diagnose either the need for surgery or death, and it had an AUC of 0.74 (95% CI: 0.65-0.83%, p < 0.0001).

CONCLUSION

 In this cohort, a combination of specific IUS markers and clinical signs of instability, abdominal wall cellulitis, plus laboratory markers were diagnostic of NEC requiring interventions.

KEY POINTS

· The diagnosis of necrotizing enterocolitis requires a combination of markers.. · The combination of specific ultrasound markers, clinical signs, and laboratory markers were diagnostic of NEC requiring intervention.. · The intestinal ultrasound performed by a trained neonatologist was the most sensitive diagnostic marker of NEC requiring surgical intervention..

Integrating Pre-test Probability and Point-of-Care Ultrasound (POCUS) in the Emergency Department (ED) Diagnosis of Small Bowel Obstruction (SBO)

Introduction A computed tomography (CT) scan and point-of-care ultrasound (POCUS) are commonly employed for diagnosing small bowel obstructions (SBOs). Prior studies demonstrated that POCUS has 90-95% sensitivity and specificity compared with CT scanning, which is the gold standard. Unlike other imaging modalities (in which the ordering and performing clinician are not the same), POCUS-performing/interpreting sonologists must recognize the risk of confirmation bias in the POCUS application. Per Bayesian analysis, the likelihood of a diagnosis being true following a diagnostic test is based on the ordering clinician's pre-test probability and the test characteristics (sensitivity and specificity, from which positive and negative likelihood ratios can be calculated). Consequently, establishing pre-test probability is important in informing downstream diagnostic or therapeutic interventions, as pre-test probability influences post-test odds. Little research has been done on the role of POCUS sonologist's pre-test probability and actual POCUS results regarding SBO. This study assessed the role of POCUS, integrating pre-test probability and POCUS results to determine post-test odds. Methods One hundred six patients were recruited on a convenience basis and underwent POCUS and CT between April 2017 and December 2022. All sonographers were credentialed in POCUS. POCUS sonologists' pre-test probabilities and POCUS and CT results were captured, which were compared. Sensitivity, specificity, LR+, and LR- were calculated, and correlations were made between pre-test probability and POCUS and CT results.  Results POCUS exhibited a sensitivity of 92% and specificity of 90%, with a corresponding positive likelihood ratio (LR+) of 9.3 and a negative likelihood ratio (LR-) of 0.09 for diagnosing SBO. Among patients with a high pre-test probability of SBO, a negative ultrasound yielded post-test odds of 0.4%, whereas a positive POCUS yielded post-test odds of 39.6%. Among patients with a low pre-test probability, a negative POCUS resulted in post-test odds of 0%, while a positive POCUS led to post-test odds of 2.1%, yielding a number needed to scan (NNS) of ~50 to identify a patient with an SBO on CT. Conclusion This study confirmed POCUS's sensitivity and specificity of ~90-95% and a corresponding LR+ of 9.2 and LR- of 0.9. Pre-test probability substantially affected post-test odds. Patients with a high pre-test probability and a positive POCUS had post-test odds of 39.6 and should have a confirmatory CT, while those with a negative POCUS have very low post-test odds and very likely will not benefit from CT. Patients with low pre-test probability and a positive POCUS have post-test odds of 2.1%, similar to the Wells Score and HEART score; such patients may not benefit from a CT, though clinicians should use their judgment/discretion. Patients with a low pre-test probability and a negative POCUS have post-test odds of 0% and should not have a CT. Among low pre-test probability patients, the NNS was ~50 to identify patients with an SBO on CT.

Home Ultrasound: A Contemporary and Valuable Tool for Palliative Medicine

This narrative review explores the application of point-of-care ultrasound (POCUS) in palliative care and its feasibility in home care settings. POCUS has the potential to streamline diagnostic strategies without patient transfer to the hospital, expedite timely symptomatic relief, and reduce complications from specific palliative interventions. The advent of handheld ultrasound devices has made it an attractive diagnostic and interventional adjunct in acute palliative care. POCUS has gained widespread acceptance as part of routine care in emergency medicine and intensive care, guiding certain procedures and increasing their safety. The modernization and miniaturization of ultrasound equipment have made ultra-portable devices available, allowing for better-quality images at affordable prices. Handheld devices have the potential to revolutionize everyday clinical practice in home-based palliative care, contributing to important bedside clinical decisions. Palliative care patients often require diagnostic examinations in the last months of their lives, with CT being the most frequently performed imaging procedure. However, CT imaging is associated with high costs and burdens, leading to increased suffering and impaired quality of life. Clinical ultrasound, a dialogic imaging modality, offers a safer and more efficient approach to palliative care. POCUS applications, which are cost-effective, non-invasive, and well-tolerated, can be used to improve patient satisfaction and diagnostic understanding. POCUS is a valuable tool in palliative care, improving diagnostic accuracy and reducing the time to diagnosis for various pathologies. It is a standard of care for many procedures and improves patient safety. However, there are limitations to POCUS in palliative care, such as operator-dependent examination variability and limited availability of trained professionals. To overcome these limitations, palliative care physicians should receive mandatory training in POCUS, which can be incorporated into the core curriculum. Additionally, ultrasound teleconsulting can assist less experienced examiners in real-time examinations. The literature on POCUS in palliative care is limited, but research on patient-oriented outcomes is crucial. POCUS should be considered a supplement to good clinical reasoning and regulated radiological evaluations.

Point of Care Abdominal Ultrasound

Abdominal pain is a common emergency department complaint, and point-of-care ultrasound (POCUS) of the abdomen is increasingly being utilized to evaluate clinical manifestations. It aids in accurate diagnoses and assists in procedures, particularly in emergency and critical care settings. Imaging is often required to confirm the etiology of abdominal pain. POCUS provides the benefit of avoiding radiation exposure and enables quicker diagnosis compared to computed tomography scans. There is growing evidence of the diagnostic accuracy for numerous abdominal POCUS applications, including appendicitis, intussusception, diverticulitis, gastric ultrasound and contrast-enhanced ultrasound.

Guidance for clinical practice using emergency and point-of-care ultrasonography

Owing to the miniaturization of diagnostic ultrasound scanners and their spread of their bedside use, ultrasonography has been actively utilized in emergency situations. Ultrasonography performed by medical personnel with focused approaches at the bedside for clinical decision-making and improving the quality of invasive procedures is now called point-of-care ultrasonography (POCUS). The concept of POCUS has spread worldwide; however, in Japan, formal clinical guidance concerning POCUS is lacking, except for the application of focused assessment with sonography for trauma (FAST) and ultrasound-guided central venous cannulation. The Committee for the Promotion of POCUS in the Japanese Association for Acute Medicine (JAAM) has often discussed improving the quality of acute care using POCUS, and the "Clinical Guidance for Emergency and Point-of-Care Ultrasonography" was finally established with the endorsement of JAAM. The background, targets for acute care physicians, rationale based on published articles, and integrated application were mentioned in this guidance. The core points include the fundamental principles of ultrasound, airway, chest, cardiac, abdominal, and deep venous ultrasound, ultrasound-guided procedures, and the usage of ultrasound based on symptoms. Additional points, which are currently being considered as potential core points in the future, have also been widely mentioned. This guidance describes the overview and future direction of ultrasonography for acute care physicians and can be utilized for emergency ultrasound education. We hope this guidance will contribute to the effective use of ultrasonography in acute care settings in Japan.

Point-of-Care Ultrasound-History, Current and Evolving Clinical Concepts in Emergency Medicine

Point-of-care ultrasound (PoCUS) has become an indispensable standard in emergency medicine. Emergency medicine ultrasound (EMUS) is the application of bedside PoCUS by the attending emergency physician to assist in the diagnosis and management of many time-sensitive health emergencies. In many ways, using PoCUS is not only the mere application of technology, but also a fusion of already existing examiner skills and technology in the context of a patient encounter. EMUS practice can be defined using distinct anatomy-based applications. The type of applications and their complexity usually depend on local needs and resources, and practice patterns can vary significantly among regions, countries, or even continents. A different approach suggests defining EMUS in categories such as resuscitative, diagnostic, procedural guidance, symptom- or sign-based, and therapeutic. Because EMUS is practiced in a constantly evolving emergency medical setting where no two patient encounters are identical, the concept of EMUS should also be practiced in a fluid, constantly adapting manner driven by the physician treating the patient. Many recent advances in ultrasound technology have received little or no attention from the EMUS community, and several important technical advances and research findings have not been translated into routine clinical practice. The authors believe that four main areas have great potential for the future growth and development of EMUS and are worth integrating: 1. In recent years, many articles have been published on novel ultrasound applications. Only a small percentage has found its way into routine use. We will discuss two important examples: trauma ultrasound that goes beyond e-FAST and EMUS lung ultrasound for suspected pulmonary embolism. 2. The more ultrasound equipment becomes financially affordable; the more ultrasound should be incorporated into the physical examination. This merging and possibly even replacement of aspects of the classical physical exam by technology will likely outperform the isolated use of stethoscope, percussion, and auscultation. 3. The knowledge of pathophysiological processes in acute illness and ultrasound findings should be merged in clinical practice. The translation of this knowledge into practical concepts will allow us to better manage many presentations, such as hypotension or the dyspnea of unclear etiology. 4. Technical innovations such as elastography; CEUS; highly sensitive color Doppler such as M-flow, vector flow, or other novel technology; artificial intelligence; cloud-based POCUS functions; and augmented reality devices such as smart glasses should become standard in emergencies over time.

Clinical Features vs CT Findings to Estimate Need for Surgery in Small Bowel Obstruction

This comparative effectiveness research compares the ability of clinical features vs clinical features with computed tomography (CT) to estimate the need for small bowel obstruction surgery.

The Role of Imaging in the Pre- and Postoperative Evaluation of Inguinal Hernia

Inguinal hernia repair is the most frequently performed surgical procedure. Imaging has a fundamental role in initial assessment and postoperative evaluation of inguinal hernias. Clinical implications of radiology in the preoperative setting include diagnosis of occult/complicated hernias and enhancement of diagnostic certainty. Postoperatively, imaging may assist the detection and characterization of complications. Familiarity with the normal appearance of the postoperative groin area and surgical techniques is required to avoid misinterpretation. This pictorial essay provides an overview of the expected postoperative imaging findings and highlights the role of imaging in the pre- and postoperative evaluation of inguinal hernias, with emphasis on ultrasonography.

Multi-center analysis of point-of-care ultrasound for small bowel obstruction: A systematic review and individual patient-level meta-analysis

OBJECTIVE

The study aimed to assess the diagnostic accuracy of point-of-care ultrasound (POCUS) in identifying small bowel obstruction (SBO) and to investigate the impact of clinician experience level and body mass index (BMI) on POCUS performance for diagnosing SBO in the Emergency Department.

METHODS

We systematically searched PubMed and Cochrane databases from January 2011-2022. We performed a meta-analysis using individual patient-level data from prospective diagnostic accuracy studies from which we obtained data from the corresponding authors. Overall test characteristics and subgroup analysis across clinician experience levels and a range of BMI were calculated. The primary outcome was SBO as the final diagnosis during hospitalization.

RESULTS

We included Individual patient data from 433 patients from 5 prospective studies. Overall, 33% of patients had a final diagnosis of SBO. POCUS had 83.0% (95%CI 71.7%-90.4%) sensitivity and 93.0% (95%CI 55.3%-99.3%) specificity; LR+ was 11.9 (95%CI 1.2-114.9) and LR- was 0.2 (95%CI 0.1-0.3). Residents had exhibited a sensitivity of 73.0% (95%CI 56.6%-84.9%) and specificity of 88.2% (95%CI 58.8%-97.5%), whereas attendings had demonstrated a sensitivity of 87.7% (95%CI 71.1%-95.4%) and specificity of 91.4% (95%CI 57.4%-98.8%). Among those patients with BMI<30 kg/m², POCUS showed a sensitivity of 88.6% (95%CI 79.5%-94.7%) and a specificity of 84.0% (95%CI 75.3%-90.6%), while patients with BMI ≥ 30 kg/m² exhibited a sensitivity of 72.0% (95%CI 50.6%-87.9%) and specificity of 89.5% (95%CI 75.2%-97.1%).

CONCLUSIONS

POCUS correctly identified those patients with SBO with high sensitivity and specificity. Diagnostic accuracy was slightly reduced when performed by resident physicians and among patients with a BMI ≥ 30 kg/m².

REGISTRATION

PROSPERO registration number: CRD42022303598.

Trends in point-of-care ultrasound use among emergency medicine residency programs over a 10-year period

Background

Point-of-care ultrasound (POCUS) is increasingly utilized in emergency medicine (EM). While residents are required by the Accreditation Council for General Medical Education to complete a minimum of 150 POCUS examinations before graduation, the distribution of examination types is not well-described. This study sought to assess the number and distribution of POCUS examinations completed during EM residency training and evaluate trends over time.

Methods

This was a 10-year retrospective review of POCUS examinations across five EM residency programs. The study sites were deliberately selected to represent diversity in program type, program length, and geography. Data from EM residents graduating from 2013 to 2022 were eligible for inclusion. Exclusion criteria were residents in combined training programs, residents who did not complete all training at one institution, and residents who did not have data available. Examination types were identified from the American College of Emergency Physicians guidelines for POCUS. Each site obtained POCUS examination totals for every resident upon graduation. We calculated the mean and 95% confidence interval for each procedure across study years.

Results

A total of 535 residents were eligible for inclusion, with 524 (97.9%) meeting all inclusion criteria. The mean number of POCUS examinations per resident increased by 46.9% from 277 in 2013 to 407 in 2022. All examination types had stable or increasing frequency. Focused assessment with sonography in trauma (FAST), cardiac, obstetric/gynecologic, and renal/bladder were performed most frequently. Ocular, deep venous thrombosis, musculoskeletal, skin/soft tissue, thoracic, and cardiac examinations had the largest percentage increase in numbers over the 10-year period, while bowel and testicular POCUS remained rare.

Conclusions

There was an overall increase in the number of POCUS examinations performed by EM residents over the past 10 years, with FAST, cardiac, obstetric/gynecologic, and renal/bladder being the most common examination types. Among less common procedures, increased frequency may be needed to ensure competence and avoid skill decay for those examination types. This information can help inform POCUS training in residency and accreditation requirements.

Gastrointestinal Ultrasound in Emergency Setting

Acute bowel diseases are responsible for more than one third of subjects who were referred to the emergency department for acute abdominal pain and gastrointestinal evaluation. Gastrointestinal ultrasound (GIUS) is often employed as the first imaging method, with a good diagnostic accuracy in the setting of acute abdomen, and it can be an optimal diagnostic strategy in young females due to the radiation exposure related to X-ray and computed tomography methods. The physician can examine the gastrointestinal system in the area with the greatest tenderness by ultrasound, thus obtaining more information and data on the pathology than the standard physical examination. In this comprehensive review, we have reported the most relevant indications and advantages to using ultrasound in the investigation of abdominal acute pain.

Emergency Department Point-of-Care Ultrasound Diagnosis of a Large Bowel Obstruction Due to Metastatic Rectal Cancer: A Case Report

Large bowel obstruction (LBO) is a life-threatening condition seen most often in the geriatric population. LBO can present with nonspecific abdominal pain that can overlap with other pathologies, such as abdominal infection, acute aortic disease, intestinal perforation, and atypical acute coronary syndrome in the geriatric population. Delays in diagnosis of colonic obstruction result in significant mortality due to complications involving bowel necrosis, perforation, and sepsis. In the emergency department (ED), abdominal point-of-care ultrasound (POCUS) can diagnose LBO and facilitate the assessment of the wide differential inherent to elderly abdominal pain. The authors report a rare ED application of abdominal POCUS to facilitate rapid diagnosis of an LBO secondary to rectal cancer. 

Point-of-Care Abdominal Ultrasonography (POCUS) on the Way to the Right and Rapid Diagnosis

Point-of-Care ultrasound (POCUS) is based on target ultrasound that is performed wherever a patient is being treated, and by a non-radiologist directly involved in the patient’s care. It is used either for quick diagnosis or procedural guidance. Abdominal pain is one of the most common complaints in emergency departments, and POCUS can help in the differentiation of patients who need additional diagnostic tests or hospital treatment, which eventually reduces the overall costs of health care. POCUS has high sensitivity and specificity in abdominal pathology, it can be helpful in the evaluation of biliary, intestinal, and urinary tract, and it is especially used in trauma. Additionally, the gold standard for abdominal aortic aneurysm detection, follow up and screening is precisely this diagnostic procedure. Unfortunately, the quality of ultrasound examination can be affected by the experience of the physician performing it and the patient’s body weight. There is no doubt that POCUS is being increasingly recognized, but all motivated physicians should be provided with dedicated tutors and enough time for learning. This would certainly help to implement this diagnostic method as a routine in emergency and critical care departments, and significantly shorten the time until definitive diagnosis.

Association of MicroRNAs With Risk of Stroke: A Meta-Analysis

Objectives

Altered expression of microRNAs (miRNAs) may contribute to disease vulnerability. Studies have reported the involvement of miRNA in the pathophysiology of ischemic stroke.

Methods

We performed a meta-analysis of data from 6 studies that used a panel of miRNAs with altered expressions to diagnose ischemic stroke with the Bayesian framework. The I² test and Cochran's Q-statistic were used to assess heterogeneity. Funnel plots were generated and publication bias was assessed using Begg and Egger tests.

Results

On summary receiver operating characteristics (SROC) curve analysis, the pooled sensitivity and specificity of altered miRNA expressions for diagnosis of ischemic stroke was 0.92 (95% confidence interval [CI] 0.80–0.97) and 0.83 (95% CI 0.71–0.90), respectively; the diagnostic odds ratio was 54.35 (95% CI 20.39–144.92), and the area under the SROC curve was 0.93 (95% CI 0.90–0.95).

Conclusions

Our results showed a link between dysregulation of miRNAs and the occurrence of ischemic stroke. Abnormal miRNA expression may be a potential biomarker for ischemic stroke.

A new intestinal ultrasound integrated approach for the management of neonatal gut injury

Clinical management of gut injury has been a challenge to the clinician since the first description of necrotizing enterocolitis (NEC) about 50 years ago, and it is still poorly defined. Most of the diagnostic markers are non-specific, and there is no consensus yet on a reliable gold standard for diagnosis. This report describes our approach to integrating point of care intestinal ultrasound (IUS) as the primary radiological assessment modality with other clinical and biochemical markers.

CONCLUSIONS

This is the first clinical guideline integrating point of care IUS as a routine assessment of the gut injury. This integrated algorithm improves the quality of care of the gut injury, provides a more accurate diagnosis of NEC, and differentiates other categories of gut injury.

WHAT IS KNOWN

• Necrotizing enterocolitis is a poorly defined disease, and the routine assessment relying on AXR does not differentiate NEC from other categories of gut injury.

WHAT IS NEW

• Integrating point of care IUS with the routine clinical assessment of gut injury enables the gut injury to be classified according to the triggering factors and severity; this helps target the appropriate management.

Surgical management of adhesive small bowel obstruction: Is it still mandatory to wait? - An update

Small bowel obstruction syndromes (SBO) represent one of the main causes of emergency admission for surgical abdominal pain. The 2018 Bologna Guidelines (Ten Broek et al. 2018) recommend non-operative management at the outset if there are no signs of severity; surgery is proposed after 72h for the 20-30% of patients who fail medical management. However, these recommendations were based on old studies published at a time when laparoscopic surgery was not commonplace and when diagnostic capabilities (particularly for establishing etiology) were less developed than they are today. Additionally, the advent and development of laparoscopy and enhanced rehabilitation after surgery have led to a decrease in surgical morbidity. These guidelines are therefore now debated and several recent publications have encouraged urgent or semi-urgent surgical management for patients presenting for SBO in order to reduce morbidity, mortality, duration of hospitalization and costs, and to improve the feasibility of therapeutic laparoscopy. Prompt surgical management could also reduce the risk of recurrent small bowel obstructions. This model for early surgical management probably cannot be applied to all patients. It therefore seems important to select those patients at risk for failure of medical treatment and to identify those in whom the probability of successful laparoscopy is high. New radiological tools should allow better selection in the future. At the present time, the indications for early surgery "within 24h" should be emphasized.

Point-of-care ultrasound-first for the evaluation of small bowel obstruction: National cost savings, length of stay reduction, and preventable radiation exposure

OBJECTIVES

Computed tomography (CT) has long been the gold standard in diagnosing patients with suspected small bowel obstruction (SBO). Recently, point-of-care ultrasound (POCUS) has demonstrated comparable test characteristics to CT imaging for the diagnosis of SBO. Our primary objective was to estimate the annual national cost saving impact of a POCUS-first approach for the evaluation of SBO. Our secondary objectives were to estimate the reduction in radiation exposure and emergency department (ED) length of stay (LOS).

METHODS

We created and ran 1000 trials of a Monte Carlo simulation. The study population included all patients presenting to the ED with abdominal pain who were diagnosed with SBO. Using this simulation, we modeled the national annual cost savings in averted advanced imaging from a POCUS-first approach for SBO. The model assumes that all patients who require surgery or have non-diagnostic POCUS exams undergo CT imaging. The model also conservatively assumes that a subset of patients with diagnostic POCUS exams undergo additional confirmatory CT imaging. We used the same Monte Carlo model to estimate the reduction in radiation exposure and total ED bed hours saved.

RESULTS

A POCUS-first approach for diagnosing SBO was estimated to save a mean (±SD) of $30.1 million (±8.9 million) by avoiding 143,000 (±31,000) CT scans. This resulted in a national cumulative decrease of 507,000 bed hours (±268,000) in ED LOS. The reduction in radiation exposure to patients could potentially prevent 195 (±56) excess annual cancer cases and 98 (±28) excess annual cancer deaths.

CONCLUSIONS

If adopted widely and used consistently, a POCUS-first algorithm for SBO could yield substantial national cost savings by averting advanced imaging, decreasing ED LOS, and reducing unnecessary radiation exposure in patients. Clinical decision tools are needed to better identify which patients would most benefit from CT imaging for SBO in the ED.

Radiation risk issues in recurrent imaging

Millions of patients benefit from medical imaging every single day. However, we have entered an unprecedented era in imaging practices wherein 1 out of 125 patients can be exposed to effective dose >50 mSv from a single CT exam and 3 out of 10,000 patients undergoing CT exams could potentially receive cumulative effective doses > 100 mSv in a single day. Recurrent imaging with CT, fluoroscopically guided interventions, and hybrid imaging modalities such as positron emission tomography/computed tomography (PET/CT) is more prevalent today than ever before. Presently, we do not know the cumulative doses that patients may be receiving across all imaging modalities combined. Furthermore, patients with diseases with longer life expectancies are being exposed to high doses of radiation enabling radiation effects to manifest over a longer time period. The emphasis in the past on improving justification of imaging and optimization of technique and practice has proved useful. While that must continue, the current situation requires imaging device manufacturers to urgently develop imaging technologies that are safer for patients as high doses have been observed in patients where imaging has been justified through clinical decision-support and optimized by keeping doses below the national benchmark doses. There is a need to have a critical look at the fundamental principles of radiation protection as cumulative doses are likely to increase in the coming years.

Mors Gaudet Succurrere Vitae. The Role of Clinical Autopsy in Preventing Litigation Related to the Management of Liver and Digestive Disorders

Over the last 50 years, the number of clinical autopsies has decreased, but their role in assessing cause of death and clinical performance is still acknowledged. Few publications have studied their role in malpractice claim prevention. The paper aims to highlight the role of clinical autopsy in preventing errors and improve healthcare quality. A retrospective study was conducted on 28 clinical autopsies performed between 2015 and 2021 on patients dead unexpectedly after procedures for the diagnosis and treatment of digestive and hepatic diseases. After an accurate analysis of medical records and consultation with healthcare professionals, all cases were subjected to autopsy and histopathology. The data obtained were analyzed and shared with the risk-management team to identify pitfalls and preventive strategies. Post-mortem evaluations confirmed the clinical diagnosis only in six cases (21.4%). Discordances were observed in 10 cases (35.7%). In the remaining 12 cases (42.9%) the clinical diagnosis was labeled as "unknown" and post-mortem examinations made it possible to document the cause of death. Post-mortem examinations can concretely enrich hospital prevention systems and improve patient safety. The methodological approach outlined certainly demonstrates that, even in the risk-management field, "mors gaudet succurrere vitae" ("death delights in helping life").

Point-of-Care Ultrasound in the Diagnosis of an Incarcerated Inguinal Hernia

Emergency physicians can use point-of-care ultrasound to diagnose inguinal hernias as well as their potential complications, including small bowel obstruction, incarceration, and even strangulation. We provide an overview of the sonographic appearance of inguinal hernias, as well as the diagnostic criteria of serious complications. In this case report, point-of-care ultrasound findings included a non-reducible inguinal hernia associated with significant bowel dilation in multiple loops without signs of intestinal ischemia or necrosis.

Computed Tomography in Emergency Diagnosis and Management Considerations of Small Bowel Obstruction for Surgical vs. Non-surgical Approach

BACKGROUND

Small bowel obstruction (SBO) accounts for 15% of abdominal pain complaints referred to emergency departments and imposes significant financial burdens on the healthcare system. The absence of passage of flatus or stool and abdominal distention are reported as the most common symptom and a sign of SBO, respectively. Patients who do not demonstrate severe clinical or imaging findings are typically treated with conservative approaches. Patients with clinical signs of sepsis or physical findings of peritonitis are often instantly transferred to the operating room without supplementary imaging assessment. However, in cases where symptoms are non-specific, or the physical examination is challenging, such as in cases with loss of consciousness, the diagnosis can be complicated. This paper discusses the key findings detectable on Computed tomography (CT), which are vital for the emergent triage, proper treatment, and decision making in patients with speculated SBO.

METHOD

Narrative review of the literature.

RESULTS AND CONCLUSION

CT plays a key role in emergent triage, proper treatment, and decision making. It provides high sensitivity, specificity, and accuracy in the detection of early-stage obstruction and acute intestinal vascular compromise. It can also differentiate between various etiologies of this entity which is considered an important criterion in the triage of patients into surgical vs. non-surgical treatment. There are multiple CT findings, such as mesenteric edema, lack of the small-bowel feces, bowel wall thickening, fat stranding in the mesentery, and intraperitoneal fluid, which are predictive of urgent surgical exploration.

Imaging Modalities for Evaluation of Intestinal Obstruction

It is essential for the colon and rectal surgeon to understand the evaluation and management of patients with both small and large bowel obstructions. Computed tomography is usually the most appropriate and accurate diagnostic imaging modality for most suspected bowel obstructions. Additional commonly used imaging modalities include plain radiographs and contrast imaging/fluoroscopy, while less commonly utilized imaging modalities include ultrasonography and magnetic resonance imaging. Regardless of the imaging modality used, interpretation of imaging should involve a systematic, methodological approach to ensure diagnostic accuracy.

Transgastric Abdominal Ultrasonography in Anesthesia and Critical Care: Review and Proposed Approach

The use of transesophageal echocardiography (TEE) in the operating room and intensive care unit can provide invaluable information on cardiac as well as abdominal organ structures and function. This approach may be particularly useful when the transabdominal ultrasound examination is not possible during intraoperative procedures or for anatomical reasons. This review explores the role of transgastric abdominal ultrasonography (TGAUS) in perioperative medicine. We describe several reported applications using 10 views that can be used in the diagnosis of relevant abdominal conditions associated with organ dysfunction and hemodynamic instability in the operating room and the intensive care unit.

Auscultation of Bowel Sounds and Ultrasound of Peristalsis Are Neither Compartmentalized Nor Correlated

Objective  Auscultation of bowel sounds has been taught as a component of the physical examination since the beginning of the 20th century. However, there has been little research or consensus on the significance of listening in different quadrants. Some textbooks indicate that bowel sounds are the result of peristalsis in that region, while others state that bowel sounds can be generalized over the entire abdominal wall. With ultrasonography, peristalsis can be visualized in a dynamic and non-invasive manner. The purpose of this study was to determine the relationship between auscultation of bowel sounds and visualization of peristalsis with ultrasound, to understand whether or not bowel sounds and peristalsis are compartmentalized. Methods  Study participants quietly lay supine, while one investigator positioned an ultrasound probe on the abdomen visualizing the small intestine, and a second investigator placed an EKO Digital Stethoscope (Eko Devices, Inc., Oakland, CA) directly adjacent to the probe auscultate for bowel sounds. During a two-minute interval, a third investigator noted every time a bowel sound was heard (A+), peristalsis was seen (U+), or a combined event (C+) occurred, recording the total number of events. Measurements were recorded from four quadrants (right upper quadrant {RUQ}, left upper quadrant {LUQ}, right lower quadrant {RLQ}, left lower quadrant {LLQ}) and the periumbilical region (PUR). Fisher Exact test was used to determine whether there were significant differences between the number of bowel sounds heard but not seen (A+) and those seen but not heard (U+) with sounds that were both seen and heard (C+). Significance was determined with p < 0.05. Results  A total of 16 participants were included, with a combined 973 discrete bowel events, both auscultated and visualized. No quadrant showed a significant correlation between an isolated sound (A+) or peristalsis (U+) and a combined event (C+), indicating there were many events where an auscultated sound failed to correlate with observed peristalsis, and vice versa. The average p-value was 0.544, with a range of 0.052-1.00. Conclusion  This study showed that there is no significant correlation between auscultated bowel sounds and peristalsis within a given region. This study calls into question whether auscultation of all four quadrants provides more meaningful information than auscultation of one central point of the abdomen.

Ultrasound of Small Bowel Obstruction: A Pictorial Review

Small bowel obstruction (SBO) is a common condition requiring urgent attention that may involve surgical treatment. Imaging is essential for the diagnosis and characterization of SBO because the clinical presentation and results of laboratory tests may be nonspecific. Ultrasound is an excellent initial imaging modality for assisting physicians in the rapid and accurate diagnosis of a variety of pathologies to expedite management. In the case of SBO diagnosis, ultrasound has an overall sensitivity of 92% (95% CI: 89–95%) and specificity of 93% (95% CI: 85–97%); the aim of this review is to examine the criteria for the diagnosis of SBO by ultrasound, which can be divided into diagnostic and staging criteria. The diagnostic criteria include the presence of dilated loops and abnormal peristalsis, while the staging criteria are represented by parietal and valvulae conniventes alterations and by the presence of free extraluminal fluid. Ultrasound has reasonably high accuracy compared to computed tomography (CT) scanning and may substantially decrease the time to diagnosis; moreover, ultrasound is also widely used in the monitoring and follow-up of patients undergoing conservative treatment, allowing the assessment of loop distension and the resumption of peristalsis.

Abdominal Pain in the Elderly Patient: Point-of-care Ultrasound Diagnosis of Small Bowel Obstruction

CASE PRESENTATION

A 67-year-old female presented to the emergency department (ED) complaining of generalized abdominal pain, nausea, and vomiting. Point-of-care ultrasound (POCUS) demonstrated dilated bowel loops measuring up to 4.1 centimeters and localized free fluid, consistent with a small bowel obstruction (SBO). A nasogastric tube was placed without complications. The patient was admitted to the hospital and conservatively managed with an uncomplicated course.

DISCUSSION

In elderly patients with abdominal pain, POCUS is an excellent initial imaging modality to assist emergency physicians in rapid and accurate diagnosis of a variety of pathologies to expedite management. Point-of-care ultrasound can be used to rule out and evaluate for conditions encountered in emergency medicine, including acute cholecystitis, renal colic, abdominal aortic aneurysm, and intraperitoneal free fluid. As demonstrated in our case presentation, POCUS had an integral role in the early diagnosis and management of a SBO.

Bowel ultrasonography in acute abdomen: beyond acute appendicitis

Acute abdomen is a common reason for consultation in the emergency department. A broad spectrum of entities, including diverse diseases of the gastrointestinal tract, can cause acute abdomen. Although computed tomography is the technique most widely used to evaluate acute abdomen in the emergency department, abdominal ultrasound is often performed first and allows bowel disease to be suspected. This article describes the ultrasound features of diverse bowel diseases that can cause acute abdomen, such as acute diverticulitis, bowel obstruction, gastrointestinal perforation, bowel ischemia, intraabdominal fat necrosis, and miscellaneous processes such as endometriosis, foreign bodies, or vasculitis. Radiologists must be familiar with the different features of abnormal bowel that can be detected incidentally in patients without clinical suspicion of bowel disease. This article focuses on ultrasonographic signs of bowel disease; other articles in this series cover the ultrasonographic signs of acute appendicitis, inflammatory bowel disease, and infectious diseases.

Adhesive Small Bowel Obstruction and the six w's: Who, How, Why, When, What, and Where to diagnose and operate?

BACKGROUND AND AIMS

Approximately 75% of patients admitted with small bowel obstruction have intra-abdominal adhesions as their cause (adhesive small bowel obstruction). Up to 70% of adhesive small bowel obstruction cases, in the absence of strangulation and bowel ischemia, can be successfully treated with conservative management. However, emerging evidence shows that surgery performed early during the first episode of adhesive small bowel obstruction is highly effective. The objective of this narrative review is to summarize the current evidence on adhesive small bowel obstruction management strategies.

MATERIALS AND METHODS

A review of the literature published over the last 20 years was performed to assess Who, hoW, Why, When, What, and Where diagnose and operate on patients with adhesive small bowel obstruction.

RESULTS

Adequate patient selection through physical examination and computed tomography is the key factor of the entire management strategy, as failure to detect patients with strangulated adhesive small bowel obstruction and bowel ischemia is associated with significant morbidity and mortality. The indication for surgical exploration is usually defined as a failure to pass contrast into the ascending colon within 8-24 h. However, operative management with early adhesiolysis, defined as operative intervention on either the calendar day of admission or the calendar day after admission, has recently shown to be associated with an overall long-term survival benefit compared to conservative management. Regarding the surgical technique, laparoscopy should be used only in selected patients with an anticipated single obstructing band, and there should be a low threshold for conversion to an open procedure in cases of high risk of bowel injuries.

CONCLUSION

Although most adhesive small bowel obstruction patients without suspicion of bowel strangulation or gangrene are currently managed nonoperatively, the long-term outcomes following this approach need to be analyzed in a more exhaustive way, as surgery performed early during the first episode of adhesive small bowel obstruction has shown to be highly effective, with a lower rate of recurrence.

Diagnostic accuracy of ultrasound for small bowel obstruction: A systematic review and meta-analysis

PURPOSE

Accurate diagnosis of small bowel obstruction (SBO) remains challenging. The evidence of the diagnostic accuracy of ultrasound varies among studies, with reporting sensitivity ranging from 82 % to 100 % and specificity ranging from 54 % to 100 %. The aim of our study is to perform a systematic review and meta-analysis to investigate the accuracy of ultrasound for diagnosing SBO.

METHOD

The PubMed, EMBASE, Cochrane Library, Web of Science, and Scopus databases were searched from database inception to March 2020. Randomized controlled trials, quasi randomized studies, and prospective or retrospective cohort studies that evaluated the diagnostic performance of ultrasound for the diagnosis of bowel obstruction in adult patients (age ≥ 16 years) were eligible. The QUADAS-2 tool was used to assess the quality of the included studies. The pooled sensitivities, specificities were analyzed using a bivariate random-effects model. (PROSPERO ID: CRD42020170010).

RESULTS

Fifteen studies, with most rating as a moderate risk of bias, met the inclusion criteria. The pooled sensitivity and specificity were 92 % (95 % CI: 89%-95%) and 93 % (95 % CI: 85%-97%), respectively. Subgroup analysis revealed no significant differences in sensitivity when ultrasound was performed on different continents, in different settings, and under different reference standards. However, the specificity was significantly lower when ultrasound was performed in the North America, in the emergency department, and when computed tomography was used as the only reference standard.

CONCLUSIONS

Overall, ultrasound is a highly sensitive and specific tool for the diagnosis of SBO. Using ultrasound to rule in patients with SBO should be used with caution, as variations in the specificity were observed in different study setting, operators from different continents and reference standards used.

Point-of-Care Ultrasound: Applications in Low- and Middle-Income Countries

Purpose of Review

This review highlights the applications of point-of-care ultrasound in low- and middle-income countries and shows the diversity of ultrasound in the diagnosis and management of patients.

Recent Findings

There is a paucity of data on point-of-care ultrasound in anesthesiology in low- and middle-income countries. However, research has shown that point-of-care ultrasound can effectively help manage infectious diseases, as well as abdominal and pulmonary pathologies.

Summary

Point-of-care ultrasound is a low-cost imaging modality that can be used for the diagnosis and management of diseases that affect low- and middle-income countries. There is limited data on the use of ultrasound in anesthesiology, which provides clinicians and researchers opportunity to study its use during the perioperative period.

Gastrointestinal Ultrasound (GIUS) in Intestinal Emergencies - An EFSUMB Position Paper

An interdisciplinary group of European experts summarizes the value of gastrointestinal ultrasound (GIUS) in the management of three time-critical causes of acute abdomen: bowel obstruction, gastrointestinal perforation and acute ischemic bowel disease. Based on an extensive literature review, statements for a targeted diagnostic strategy in these intestinal emergencies are presented. GIUS is best established in case of small bowel obstruction. Metanalyses and prospective studies showed a sensitivity and specificity comparable to that of computed tomography (CT) and superior to plain X-ray. GIUS may save time and radiation exposure and has the advantage of displaying bowel function directly. Gastrointestinal perforation is more challenging for less experienced investigators. Although GIUS in experienced hands has a relatively high sensitivity to establish a correct diagnosis, CT is the most sensitive method in this situation. The spectrum of intestinal ischemia ranges from self-limited ischemic colitis to fatal intestinal infarction. In acute arterial mesenteric ischemia, GIUS may provide information, but prompt CT angiography is the gold standard. On the other end of the spectrum, ischemic colitis shows typical ultrasound features that allow correct diagnosis. GIUS here has a diagnostic performance similar to CT and helps to differentiate mild from severe ischemic colitis.

Point of care ultrasound for rapid assessment and treatment of palliative care patients in acute medical settings

The combination of an ageing population with improving survival in malignant and non-malignant disease processes results in a growing cohort of patients with advanced or end-stage chronic diseases who require acute medical care. Emergency care has historically been stereotyped as the identification and treatment of acute life-threatening problems. Although palliative care may be considered to be new to the formal curriculum of emergency medicine, in many domains the ultrasound skillset of a physician in acute medical care can be efficaciously deployed the benefit of patients with both malignant and non-malignant disease processes that require palliative care in the full breadth of acute healthcare settings. In diagnostic domains (abdominal pain, urinary tract obstruction, dyspnoea, venous thromboembolism and musculoskeletal pain) and for specific intervention guidance (thoracentesis, paracentesis, venous access, regional anaesthesia and musculoskeletal interventions) we suggest that POCUS has the potential to streamline improve patient satisfaction, streamline diagnostic strategies, optimise patient length of stay, expedite timely symptomatic relief and reduce complications in this important patient population. POCUS is a mandatory competence in the European curriculum of internal medicine, and specific training programs which cover applications in the domains of palliative care in acute care settings are available. Supervision, quality assurance and appropriate documentation are required. We expect that as the availability of mobile units suitable for point of care applications increases, these applications should become standard of care in the acute management of patients who require palliative care.

Emergency Physician-Performed Bedside Ultrasound of Gastric Volvulus

Gastric volvulus (GV) is a seldomly encountered life-threatening condition that necessitates rapid diagnosis in the emergency department (ED). The diagnosis of GV is traditionally established with cross-sectional imaging and/or endoscopy with surgical confirmation. The potential role of point-of-care ultrasound (POCUS) as a bedside tool to support the early identification of GV by emergency physicians (EPs) has not been thoroughly investigated. This case report describes the expeditious diagnosis and ED management of acute GV by implementing EP-performed POCUS into critical decision making.

Diagnostic Accuracy of Point-of-Care Ultrasound for Intussusception in Children Presenting to the Emergency Department: A Systematic Review and Meta-analysis

INTRODUCTION

Ileocolic intussusception is a common cause of pediatric bowel obstruction in young children but can be difficult to diagnose clinically due to vague abdominal complaints. If left untreated, it may cause significant morbidity. Point-of-care ultrasound (POCUS) is a rapid, bedside method of assessment that may potentially aid in the diagnosis of intussusception. The purpose of this systematic review and meta-analysis was to determine the diagnostic accuracy of POCUS for children with suspected ileocolic intussusception by emergency physicians (EP).

METHODS

We conducted a systematic search on PubMed, Embase, CINAHL, LILACS, the Cochrane databases, Google Scholar, as well as conference abstracts, and assessed bibliographies of selected articles for all studies evaluating the accuracy of POCUS for the diagnosis of intussusception in children. We dual extracted data into a predefined worksheet and performed quality analysis with the QUADAS-2 tool. Data were summarized and a meta-analysis was performed.

RESULTS

Six studies (n = 1303 children) met our inclusion criteria. Overall, 11.9% of children had intussusception. POCUS was 94.9% (95% confidence interval [CI], 89.9% to 97.5%) sensitive and 99.1% (95% CI, 94.7% to 99.8%) specific with a likelihood ratio (LR)+ of 105 (95% CI, 18 to 625) and a LR- of 0.05 (95% CI, 0.03 to 0.10).

CONCLUSION

POCUS by EPs is highly sensitive and specific for the identification of intussusception for children presenting to the emergency department.

Ultrasound Signs in the Diagnosis and Staging of Small Bowel Obstruction

Ultrasound (US) is highly accurate in the diagnosis of small bowel obstruction (SBO). Because the indications for and timing of surgical intervention for SBO have changed over the past several decades, there is a widespread assumption that the majority of patients with simple SBO may be conservatively managed; in this scenario, staging SBO is crucial. This study evaluated the association between morphological and functional US signs in the diagnosis and staging (simple, decompensated and complicated), and the associations and prevalence of US signs correlated with clinical or surgical outcome. The US signs were divided into diagnostic (dilated bowel loops and altered kinesis) and staging criteria (extraluminal free fluid, parietal and villi alterations). We performed a retrospective, single-center cohort, observational study examining the prevalence of morphologic and functional US signs in the staging of simple, decompensated and complicated SBO. The most significant US signs were dilated bowel loops (100%), hypokinesis (90.46%), thickened walls (82.54%) and free fluid (74.60%). By linear regression, free fluid was positively correlated to US staging in both univariate and multivariate analysis; that is, the more advanced the stage of SBO, the more probable the presence of free fluid between the bowel loops. In univariate analysis only, we found a positive correlation between US staging/thickened walls and the prominence of valvulae conniventes. Additionally, the multivariate analysis indicated that parietal stratification and bowel jump kinesis were negative predictors for US staging in comparison to other US signs. In addition, we found significant associations between conservative treatment or surgery and hypokinesis (p = 0.0326), akinesis (p = 0.0326), free fluid (p = 0.0013) and prominence of valvulae conniventes (p = 0.011). Free fluid in particular was significantly less present in patients that were conservatively treated (p = 0.040). We conclude that the US staging of SBO may be crucial, with a valuable role in the initial diagnosis and staging of the pathology, saving time and reducing total radiation exposure to the patient.

Nongynecologic Causes of Pelvic Pain: Ultrasound First

Ultrasonography (US) is often the first-line imaging study used to evaluate women who present with acute or chronic pelvic pain. Detection of nongynecologic causes of pelvic pain is critical, because delay in diagnosis can cause significant morbidity and mortality. Evaluation of these entities requires a variety of transducers to achieve optimal imaging depth and changes in patient positioning. Specific imaging techniques (such as graded compression) may be required if bowel pathology is suspected. Contrast-enhanced ultrasonography is increasingly used to improve detection of certain entities. The US appearance of common gastrointestinal and urinary tract-related causes of pelvic pain is reviewed.

Diagnostic utility of CT for small bowel obstruction: Systematic review and meta-analysis

BACKGROUND

To perform a systematic review and meta-analysis evaluating the diagnostic performance of computed tomography (CT) for small bowel obstruction (SBO), including diagnostic accuracy, ischemia, predicting surgical intervention, etiology and transition point.

METHODS

PubMed/MEDLINE and related databases were searched for research articles published from their inception through August 2018. Findings were pooled using bivariate random-effects and summary receiver operating characteristic curve models. Meta-regression and subgroup analyses were performed to evaluate whether publication year, patient age, enhanced CT, slice thickness and pathogenesis affected classification accuracy.

RESULTS

In total, 45 studies with a total of 4004 patients were included in the analysis. The pooled sensitivity and specificity of CT for SBO were 91% (95% confidence interval [CI]: 84%, 95%) and 89% (95% CI: 81%, 94%), respectively, and there were no differences in the subgroup analyses of age, publication year, enhanced CT and slice thickness. For ischemia, the pooled sensitivity and specificity was 82% (95% CI: 67%, 91%) and 92% (95% CI: 86%, 95%), respectively. No difference was found between enhanced and unenhanced CT based on subgroup analysis; however, high sensitivity was found in adhesive SBO compared with routine causes (96% vs. 78%, P = 0.03). The pooled sensitivity and specificity for predicting surgical intervention were 87% and 73%, respectively. The accuracy for etiology of adhesions, hernia and tumor was 95%, 70% and 82%, respectively. In addition, the pooled sensitivity and specificity for transition point was 92% and 77%, respectively.

CONCLUSIONS

CT has considerable accuracy in diagnosis of SBO, ischemia, predicting surgical intervention, etiology and transition point.

Development of a nomogram to predict small bowel obstruction using point-of-care ultrasound in the emergency department

OBJECTIVE

Early diagnostic prediction in patients with small bowel obstruction (SBO) can improve time to definitive management and disposition in the emergency department. We sought to develop a nomogram to leverage point-of-care ultrasound (POCUS) and maximize accuracy of prediction of SBO diagnosis.

METHODS

Using data from a prospective cohort of 125 patients with suspected SBO who were evaluated with POCUS in the ED, we developed a nomogram integrating age, gender, comorbidities, prior abdominal surgery, physician's pre-test probability, and POCUS findings to determine post-test risk of SBO. The primary outcome was to develop a nomogram to allow calculating output probabilities for predictive models using POCUS findings. The discriminative ability of the nomogram was tested using a C-statistics, calibration plots, and receiver operating characteristic curves.

RESULTS

The derivation cohort included 125 patients with a median age of 54 years who underwent POCUS for a suspected SBO. One-fourth of the patients (25.6% [32/125]) had SBO. Using a retrospective stepwise selection of clinically important variables with the POCUS results, the final nomogram incorporated four relevant factors for the prediction of SBO: small bowel diameter (odds ratio [OR] per 1 mm increase, 1.10; 95% CI, 1.03-1.17; P = 0.001), positive free intraperitoneal fluid between bowel loops (OR, 8.19; 95% CI, 2.62-25.62; P < 0.001), clinician's moderate (OR, 5.94; 95% CI, 0.83-42.57; P = 0.08) or high pretest probability (OR, 11.26; 95% CI, 1.44-88.25; P = 0.02), and patient age (OR per 1 year increase, 1.03; 95% CI, 1.00 to1.07; P = 0.08).The discriminative ability and calibration of the nomogram revealed good predictive ability as indicated by the C-statistic of 0.89 for the SBO diagnosis.

CONCLUSION

A unique nomogram incorporating patient age, physician pretest probability of SBO, and POCUS measurements of small bowel diameter and the presence of free intraperitoneal fluid between bowel loops was developed to accurately predict the diagnosis of SBO in the emergency department. The nomogram should be externally validated in a novel cohort of patients at risk for SBO to better assess predictability and generalizability.

Diagnostic Accuracy of Ultrasound in the Diagnosis of Small Bowel Obstruction

INTRODUCTION

Small bowel obstruction (SBO) is a common presentation to the Emergency Department (ED). This study aimed to analyze the accuracy of ultrasound (US) in diagnosing and staging SBO.

OBJECTIVES

The main object of this study was to analyze the accuracy of ultrasound in diagnosing and staging SBO compared to CT.

METHODS

Retrospectively, stable patients with an ultrasonographic diagnosis of SBO who underwent abdominal CT immediately after US and before receiving naso-intestinal decompression, were included. US criteria for the diagnosis of SBO were related to morphological and functional findings. US diagnosis of obstruction was made if fluid-filled dilated small bowel loops were detected, peristalsis was abnormal and parietal abnormalities were present. Morphologic and functional sonographic findings were assigned to three categories: simple SBO, compensated SBO and decompensated SBO. US findings were compared with the results of CT examinations: Morphologic CT findings (divided into loop, vascular, mesenteric and peritoneal signs) allowed the classification of SBO in simple, decompensated and complicated.

RESULTS

US diagnostic accuracy rates in relation to CT results were calculated: ultrasound compared to CT imaging, had a sensitivity of 92.31% (95% CI, 74.87% to 99.05%) and a specificity of 94.12% (95% CI, 71.31% to 99.85%) in the diagnosis of SBO.

CONCLUSIONS

This study, similarly to the existing literature, suggests that ultrasound is highly accurate in the diagnosis of SBO, and that the most valuable sonographic signs are the presence of dilated bowel loops ad abnormal peristalsis.