Accuracy and Interrater Reliability of Point-of-Care Ultrasonography Image Interpretation for Intussusception.

OBJECTIVES: The aim of this study was to determine the accuracy and interrater reliability of (1) point-of-care ultrasound (POCUS) image interpretation for identification of intussusception and (2) reliability of secondary signs associated with intussusception among experts compared with novice POCUS reviewers. METHODS: We conducted a planned secondary analysis of a prospective, convenience sample of children aged 3 months to 6 years who were evaluated with POCUS for intussusception across 17 international pediatric emergency departments between October 2018 and December 2020. A random sample of 100 POCUS examinations was reviewed by novice and expert POCUS reviewers. The primary outcome was identification of the presence or absence of intussusception. Secondary outcomes included intussusception size and the presence of trapped free fluid or echogenic foci. Accuracy was summarized using sensitivity and specificity, which were estimated via generalized mixed effects logistic regression. Interrater reliability was summarized via Light's κ statistics with bootstrapped standard errors (SEs). Accuracy and reliability of expert and novice POCUS reviewers were compared. RESULTS: Eighteen expert and 16 novice POCUS reviewers completed the reviews. The average expert sensitivity was 94.5% (95% confidence interval [CI], 88.6-97.5), and the specificity was 94.3% (95% CI, 90.3-96.7), significantly higher than the average novice sensitivity of 84.7% (95% CI, 74.3-91.4) and specificity of 80.4% (95% CI, 72.4, 86.7). κ was significantly greater for expert (0.679, SE 0.039) compared with novice POCUS reviewers (0.424, SE 0.044; difference 0.256, SE 0.033). For our secondary outcome measure of intussusception size, κ was significantly greater for experts (0.661, SE 0.038) compared with novices (0.397, SE 0.041; difference 0.264, SE 0.029). Interrater reliability was weak for expert and minimal for novice reviewers regarding the detection of trapped free fluid and echogenic foci. CONCLUSIONS: Expert POCUS reviewers demonstrate high accuracy and moderate interrater reliability when identifying intussusception via image interpretation and perform better than novice reviewers.

Diagnostic Accuracy of Point-of-Care Ultrasound for Intussusception: A Multicenter, Noninferiority Study of Paired Diagnostic Tests.

STUDY OBJECTIVE: To determine the diagnostic accuracy of point-of-care ultrasound (POCUS) performed by experienced clinician sonologists compared to radiology-performed ultrasound (RADUS) for detection of clinically important intussusception, defined as intussusception requiring radiographic or surgical reduction. METHODS: We conducted a multicenter, noninferiority, observational study among a convenience sample of children aged 3 months to 6 years treated in tertiary care emergency departments across North and Central America, Europe, and Australia. The primary outcome was diagnostic accuracy of POCUS and RADUS with respect to clinically important intussusception. Sample size was determined using a 4-percentage-point noninferiority margin for the absolute difference in accuracy. Secondary outcomes included agreement between POCUS and RADUS for identification of secondary sonographic findings. RESULTS: The analysis included 256 children across 17 sites (35 sonologists). Of the 256 children, 58 (22.7%) had clinically important intussusception. POCUS identified 60 (23.4%) children with clinically important intussusception. The diagnostic accuracy of POCUS was 97.7% (95% confidence interval [CI] 94.9% to 99.0%), compared to 99.3% (95% CI 96.8% to 99.9%) for RADUS. The absolute difference between the accuracy of RADUS and that of POCUS was 1.5 percentage points (95% CI -0.6 to 3.6). Sensitivity for POCUS was 96.6% (95% CI 87.2% to 99.1%), and specificity was 98.0% (95% CI 94.7% to 99.2%). Agreement was high between POCUS and RADUS for identification of trapped free fluid (83.3%, n=40/48) and decreased color Doppler signal (95.7%, n=22/23). CONCLUSION: Our findings suggest that the diagnostic accuracy of POCUS performed by experienced clinician sonologists may be noninferior to that of RADUS for detection of clinically important intussusception. Given the limitations of convenience sampling and spectrum bias, a larger randomized controlled trial is warranted.

Diagnostic Accuracy of Point-Of-Care Ultrasound for Intussusception Performed by Pediatric Emergency Medicine Physicians.

BACKGROUND: Intussusception (INT) is a common cause of bowel obstruction in young children. Delay in diagnosis can lead to significant morbidity and mortality. There have been several studies evaluating early point-of-care ultrasound (POCUS) in the diagnosis of INT by nonradiologists. OBJECTIVE: Our objective was to determine the diagnostic accuracy of POCUS by novice sonographer pediatric emergency medicine physicians (PEM-Ps) who received focused US training for diagnosing INT. METHODS: We performed a prospective observational study including 17 PEM-Ps (14 attendings, 3 fellows) trained to perform abdominal US for INT. Children suspected of having INT received POCUS performed and interpreted by a PEM-P, followed by a US study performed by a certified ultrasonographer and interpreted by an attending pediatric radiologist. Diagnostic concordance between PEM-P-and radiology-performed US (RPUS) results was assessed. RESULTS: One hundred patients were enrolled; median patient age was 24 months. There was excellent diagnostic agreement for presence or absence of INT between PEM-Ps and RPUS (97% of cases; κ = 0.826). POCUS-diagnosed INT was present in 8 of 9 patients with RPUS-diagnosed INT (sensitivity 89%; 95% confidence interval [CI] 51-99%; specificity 98%; 95% CI 92-100%; positive predictive value 80%; 95% CI 44-96%; negative predictive value 99%; 95% CI 93-100%). Likelihood ratio for INT with a positive POCUS was 40.44 (95% CI 10.07-162.36) and with a negative POCUS was 0.11 (95% CI 0.02-0.72). CONCLUSIONS: POCUS performed by novice sonographers to diagnose INT has high diagnostic concordance with RPUS. Emergency department-performed POCUS is a rapid and accurate method for diagnosing INT.

Pediatric emergency medicine point-of-care ultrasound: summary of the evidence.

The utility of point-of-care ultrasound is well supported by the medical literature. Consequently, pediatric emergency medicine providers have embraced this technology in everyday practice. Recently, the American Academy of Pediatrics published a policy statement endorsing the use of point-of-care ultrasound by pediatric emergency medicine providers.  To date, there is no standard guideline for the practice of point-of-care ultrasound for this specialty. This document serves as an initial step in the detailed "how to" and description of individual point-of-care ultrasound examinations.  Pediatric emergency medicine providers should refer to this paper as reference for published research, objectives for learners, and standardized reporting guidelines.

Inflating the endotracheal tube cuff with saline to confirm correct depth using bedside ultrasonography.

Although bedside ultrasonography can accurately distinguish esophageal from tracheal intubation, it is not used to establish the correct depth of endotracheal tube insertion. As indirect sonographic markers of endotracheal tube insertion depth have proven unreliable, a method for visual verification of correct tube depth would be ideal. We describe the use of saline to inflate the endotracheal cuff to confirm correct endotracheal tube depth (at the level of the suprasternal notch) by bedside ultrasonography during resuscitation. This rapid technique holds promise during emergency intubation.

Tracheal rapid ultrasound saline test (T.R.U.S.T.) for confirming correct endotracheal tube depth in children.

OBJECTIVE: We evaluated the accuracy of tracheal ultrasonography of a saline-inflated endotracheal tube (ETT) cuff for confirming correct ETT insertion depth. METHODS: We performed a prospective feasibility study of children undergoing endotracheal intubation for surgery. Tracheal ultrasonography at the suprasternal notch was performed during transient endobronchial intubation and inflation of the cuff with saline, and with the ETT at a correct endotracheal position. Ultrasound videos were recorded at both positions, which were confirmed by fiberoptic bronchoscopy. These videos were shown to two independent blinded reviewers, who determined the presence or absence of a saline-inflated cuff. The primary outcome was accuracy of tracheal ultrasonography for appropriate ETT insertion depth. RESULTS: Forty-two patients were enrolled. For correct endotracheal versus endobronchial positioning, pooled results from the reviewers revealed a sensitivity of 98.8% (95% CI=90-100%), a specificity of 96.4% (95% CI=87-100%), a PPV of 96.5% (95% CI=87-100%), a NPV of 98.8% (95% CI=89-100%), a positive likelihood ratio of 32 (95% CI=6-185), and a negative likelihood ratio of 0.015 (95% CI=0.004-0.2). Agreement between reviewers was high (kappa co-efficient=0.93; 95% CI=0.86 to 1). The mean duration of the ultrasound exam was 4.0s (range 1.0-15.0s). CONCLUSIONS: Sonographic visualization of a saline-inflated ETT cuff at the suprasternal notch is an accurate and rapid method for confirming correct ETT insertion depth in children.