Subxiphoid View Research Articles

How many is enough? Measuring the number of FAST exams needed by emergency medicine trainees to reach competence

BackgroundFor patients with blunt abdominal trauma, the Focused Assessment with Sonography in Trauma (FAST) exam is the initial imaging modality employed to diagnose and risk stratify. A positive FAST exam in this patient population denotes intraperitoneal hemorrhage. In a hemodynamically unstable patient, it necessitates rapid surgical intervention. Ultrasound is highly dependent on the operator’s ability to obtain quality images for interpretation. Failure to obtain adequate images prevents accurate interpretation and reduce its diagnostic accuracy. Previous studies evaluating whether the FAST exam can be improved solely by experience had conflicting results. None of those studies used an objective method to evaluate the FAST exam’s quality. Our study aimed to objectively determine the number of FAST exams required by an emergency medicine (EM) resident to reach sufficient quality for independent scanning.Methods59 first-year EM residents from a single site were included in this study. All FAST exams that were saved in the Qpath archival system by the 59 EM residents, whether the exam was performed for educational or clinical purposes, were reviewed, and scored using a Task-Specific Checklist (TSC) score. This score is an objective way to assess the proficiency and quality of the FAST scan. The TSC was based on whether the imaging of 24 specific anatomic landmarks, split into four anatomic regions, was completed successfully or not. The AEMUS (Advanced EM Ultrasonography) faculty provided feedback to trainees wither electronically via Qpath or at the bedside. According to the quality of ultrasound imaging and competence (QUICK Score), if the average TSC score for the first 10 exams was 18 or higher, the resident was considered an expert. However, if the resident failed to achieve that score, we skipped the first exam performed by the resident and the average score for the second through eleventh exams was then calculated. If the resident did not achieve the desired result, the first and second exams were skipped and the average score for the remaining 10 exams was determined. This sequence was repeated until the resident achieved an average score of 18 or higher on their TSC score.ResultsIn total, 663 FAST scans performed by EM residents were scored. The average number of FAST exams needed for independent scanning is 11.23 (95% CI, 10.6-11.85). 66.1% of enrolled residents achieved an average score of 18 or higher in their first 10 FAST exams, and 33.8% of residents required more than 10 scans. The average scores for the right upper quadrant (RUQ), left upper quadrant (LUQ), pelvic, and subxiphoid views were 5 (95% CI, 4.88–5.1), 4.7 (95% CI, 4.59–4.8), 5.1 (95% CI, 4.96–5.24), and 3.7 (95% CI 3.6–3.8) respectively.ConclusionThis study demonstrated that when constructive feedback on each FAST exam was given, the average first-year emergency medicine resident achieves competency in performing FAST exams independently after completing 10–12 (average of 11.23) FAST exams. Further research is required to validate the findings.

Development and Validation of a Deep-Learning Network for Detecting Congenital Heart Disease from Multi-View Multi-Modal Transthoracic Echocardiograms.

Early detection and treatment of congenital heart disease (CHD) can significantly improve the prognosis of children. However, inexperienced sonographers often face difficulties in recognizing CHD through transthoracic echocardiogram (TTE) images. In this study, 2-dimensional (2D) and Doppler TTEs of children collected from 2 clinical groups from Beijing Children's Hospital between 2018 and 2022 were analyzed, including views of apical 4 chamber, subxiphoid long-axis view of 2 atria, parasternal long-axis view of the left ventricle, parasternal short-axis view of aorta, and suprasternal long-axis view. A deep learning (DL) framework was developed to identify cardiac views, integrate information from various views and modalities, visualize the high-risk region, and predict the probability of the subject being normal or having an atrial septal defect (ASD) or a ventricular septaldefect (VSD). A total of 1,932 children (1,255 healthy controls, 292 ASDs, and 385 VSDs) were collected from 2 clinical groups. For view classification, the DL model reached a mean [SD] accuracy of 0.989 [0.001]. For CHD screening, the model using both 2D and Doppler TTEs with 5 views achieved a mean [SD] area under the receiver operating characteristic curve (AUC) of 0.996 [0.000] and an accuracy of 0.994 [0.002] for within-center evaluation while reaching a mean [SD] AUC of 0.990 [0.003] and an accuracy of 0.993 [0.001] for cross-center test set. For the classification of healthy, ASD, and VSD, the model reached the mean [SD] accuracy of 0.991 [0.002] and 0.986 [0.001] for within- and cross-center evaluation, respectively. The DL models aggregating TTEs with more modalities and scanning views attained superior performance to approximate that of experienced sonographers. The incorporation of multiple views and modalities of TTEs in the model enables accurate identification of children with CHD in a noninvasive manner, suggesting the potential to enhance CHD detection performance and simplify the screening process.

The prevalence of congenital cardiac tumours in unselected newborns

Abstract Background Primary cardiac tumours in children are rare. The most common cardiac tumour in newborns is rhabdomyomas, associated with tuberous sclerosis in >50% of cases. The estimated prevalence is 0.14‰ in fetuses, whereas in the paediatric population, a 20-fold difference in autopsy prevalence has been reported (0.017‰ to 0.27‰). Purpose To determine the pre- and postnatal prevalence of congenital cardiac tumours in a large, population-based cohort of prenatally enrolled newborns. Methods Systematic transthoracic echocardiography (TTE), including sub-xiphoid, apical, parasternal, and suprasternal views, was performed in unselected newborns included in a population study. Participants were included at time of the routine malformation scan (weeks 18-21), which included 4-chamber view, aortic and pulmonary outflow tracts, and three-vessel view. Cardiac tumours were defined as solid, echogenic masses, and the echocardiographic description included location, size, and number (one/multiple) of the tumour. Information on subsequent diagnosis of tuberous sclerosis was collected from review of medical charts. Results A total of 25,588 newborns (age 12±8 days, 51.6% male) were enrolled and underwent TTE. Prenatally, no cardiac tumours were reported in any of the participants. Postnatally, cardiac tumours were detected in 7 newborns (4 males), corresponding to a prevalence of 0.3 [0.1; 0.6] per 1,000 live-births. Through retrospective review of the prenatal scans, a possible tumour in the ventricle was suspected in 1 of the 7 cases; the remaining 6 cases showed no signs of tumours prenatally. Sex, gestational age at birth, birth length and weight, APGAR 5-score, age and weight at TTE, and maternal age and pre-pregnancy BMI, did not significantly differ between newborns with (n=7) and without (n=25,581) cardiac tumours (all p>0.05). Smoking during pregnancy was significantly more frequent among mothers to newborns with cardiac tumours compared to the remaining cohort (29% vs 4%, p=0.023). In all 7 newborns, the cardiac tumours were located in the ventricles (5 (71%) newborns with tumours in both ventricles, 2 (29%) with tumours in the right ventricle), with multiple tumours seen in 6 (86%), and with size ranging from 2.0x1.9 mm to 10.0x5.1 mm. All 7 newborns had otherwise structurally normal hearts and no flow obstruction. Three newborns with cardiac tumours in the ventricles (43%) were diagnosed with tuberous sclerosis within 4 months after birth. Conclusions Systematic TTE in unselected newborns revealed a prevalence of congenital cardiac tumours of 0.3‰. Prenatal screening in week 18-21 did not seem efficient for identification of cardiac tumours. Cardiac tumours were located in the ventricles and were most often multiple. Cardiac tumours in the ventricles were associated with tuberous sclerosis in almost half the cases. For newborns with cardiac tumours, maternal smoking during pregnancy was common (29%).Figure 1

Establishment of reference intervals for ultrasonographically derived caudal vena cava parameters from 110 healthy, lightly sedated cats

Objectives The present study aimed to establish reference intervals (RIs) for ultrasonographically derived caudal vena cava (CVC) parameters in healthy cats. Methods A prospective, observational, experimental single-centre study involving 110 cats was conducted. Two trained operators scanned all cats in a randomised order. Two sets of cine loops per cat were conducted by each operator from the subxiphoid view with cats in lateral recumbency. Two blinded raters measured the narrowest inspiratory (CVCinsp) and widest expiratory (CVCexp) diameter over two separate respiratory cycles for each operator (four measurements in total for each rater) at the point the CVC crosses the diaphragm. The CVC collapsibility index (CVCCI) was calculated. Reference intervals and limits were calculated for CVC parameters with outliers removed to include the central 95% of CVC values and the non-parametric 90% confidence intervals (90% CIs). The CVCCI interval included the central 95th (2.5th and 97.5th) centiles bounded by the 90% CI. Intra- and inter-rater and intra- and inter-operator reliabilities were calculated for each parameter using a two-way random-effects model. A Bland–Altman plot was used to visualise the CVCCI between the two raters. Results In total, 880 measurements were included for each diameter and 440 CVCCI values were calculated. The CVC diameters were normally distributed, whereas the CVCCI was not. The calculated RIs were 1.4–6.1 mm for CVCinsp and 2.2–6.7 mm for CVCexp. The median (range) CVCCI was 23% (11–36%) with 2.5th and 97.5th centiles of 2% and 67%, respectively. There was a moderate to good intra-rater and intra-operator reliability for CVC diameter. The intra-rater reliability for the CVCCI was moderate. The inter-rater and inter-operator reliabilities for the CVCCI were poor. Conclusions and relevance The CVC RIs determined from the subxiphoid site in cats appear to be wider than those reported in dogs, and rater and operator variability is present. Whether precise measurements of CVC parameters are suitable to guide clinical decisions remains to be determined.

Ultrasound based tip location of femorally inserted central catheters into the inferior vena cava: A comparison between the transhepatic and the subcostal view.

Intraprocedural catheter tip location is currently recommended. Intracavitary EGC and ultrasound are the preferred methods of tip location for catheters with their tip in the superior vena cava or in the right atrium. Though, the best method of intraprocedural tip location for catheters with their tip in the inferior vena cava is still uncertain. One possibility is to visualize the subdiaphragmatic inferior vena cava by ultrasound, using either the transhepatic or the subxiphoid view. In this prospective study, we compared two different ultrasound windows for the visualization of the inferior vena cava (transhepatic vs subxiphoid) for the purpose of localizing the catheter tip during the insertion of femorally inserted central catheters. We studied 249 consecutive insertions of central catheters via the superficial femoral vein. Intraprocedural location of the catheter tip was performed by ultrasound, using both transhepatic and subxiphoid view. Visualization of the inferior vena cava was possible only in 81 cases (32.5%) with the subxiphoid view, but it was always possible in all 249 cases with the transhepatic view. The catheter tip was localized in 15 patients out of 81 with the subxiphoid view (18.5%); the transhepatic view allowed the visualization of the tip in all 249 patients. The applicability of the subxiphoid window has several limitations, both in terms of visualization of the inferior vena cava and localization of the catheter tip. The transhepatic view should be the preferred method for intraprocedural ultrasound localization of the catheter tip in the inferior vena cava.

Echocardiographic caudal vena cava measurements in healthy cats and in cats with congestive heart failure and non-cardiac causes of cavitary effusions

BackgroundEchocardiographic indices of the inferior vena cava have been associated with elevated right atrial pressures in humans. Hypothesis/objectivesDescribe caudal vena caval (CVC) sonographic dimensions in healthy cats compared to cats with cardiogenic cavitary effusion (CCE), cardiogenic pulmonary edema (CPE), or non-cardiac causes of cavitary effusion (NCE). Animals30 healthy control cats and 52 client-owned cats with CCE, CPE, or NCE examined at two university hospitals. MethodsSagittal 2-dimensional (2D) and M-mode CVC dimensions were acquired from the subxiphoid view. Caudal vena cava collapsibility index (CVC-CI) was calculated. Variables were compared between study groups using Kruskal–Wallis and Dunn's Bonferroni testing. Receiver operating characteristic curves were used to assess sensitivity and specificity for diagnostic categories. ResultsHealthy cats had sagittal 2D and M-mode (median, interquartile range) CVC maximal dimensions of 2.4 mm (1.3–4.0) and 3.4 mm (1.5–4.9) and CVC-CI of 52% (45.2–61.8) and 55% (47.8–61.3), respectively. The CVC maximal dimensions in healthy controls were smaller than in cats with cavitary effusions or pulmonary edema (all P<0.05). CVC-CI was different between CCE and NCE (P<0.0001) with cutoffs of CVC-CI ≤38% (2D) or ≤29% (M-mode) being 90.5% and 85.7% sensitive, and 94.4% and 100% specific for diagnosis of CCE, respectively. Conclusions and clinical importanceCaudal vena cava measurements are larger in cats with cavitary effusions and cats with CPE than healthy cats. In cats with cavitary effusion, decreased CVC-CI, ≤38% (2D) or ≤29% (M-mode), was helpful in distinguishing between cardiogenic and noncardiogenic etiology.

Anatomical Correlation for Focused Assessment With Sonography in Trauma

When learning the Focused Assessment with Sonography in Trauma (FAST) exam, anatomical orientation can be difficult, especially in the subxiphoid and upper quadrant views. To facilitate understanding in these areas, a novel in-situ cadaver dissection was used to demonstrate anatomy related to the FAST exam. In situ, because the structures remained in normal positions with adjacent organs, layers, and spaces clearly visible from the point of view of the ultrasound probe. These views were then correlated with what was seen on the ultrasound screen. The right upper quadrant and subxiphoid anatomy were viewed in a mirror to match the ultrasound images, and the left upper quadrant was viewed directly from the examiner’s position, also matching the view on the ultrasound screen. The in-situ cadaver dissection was developed as a resource to correlate FAST exam ultrasound images in the upper quadrant and subxiphoid regions with related cadaver anatomy.

P19 ECHOGRAPHIC EVALUATION OF INFERIOR VENA CAVA AND FLUID CHALLENGE RESPONSE IN PAROXYSMAL ATRIAL FIBRILLATION: A PRELIMINARY STUDY

Abstract Introduction Volume depletion can trigger atrial fibrillation through the alteration of the balance of autonomic tone. Hemodynamic response to crystalloid infusion has never been investigated in Paroxysmal AF patients. In this pilot study we have evaluated volume expansion response using Doppler echocardiogaphy in a group of patients coming to our Emergency Department because of symptomatic paroxysmal AF. Methods In a group of consecutive Paroxysmal AF patients we performed a comprehensive echocardiographic examination including Vena Cava diameters and inspiratory collapse rate (from bidimensional subxiphoid view) and including Left Ventricular Outflow time–velocity integral (as mean value of 10 consecutive cardiac cycles). Those with mitral, aortic or tricuspid regrgitation of grade higher than 2+/4+, mitral stenosis, prosthethic mitral valve, FE &amp;lt; 55%, estimated sPAP higher than 40 mmHg were excluded. Thus we selected 13 patients (mean age 67,25 years, range 34–83). Time–velocity integral of LVOT was re–evaluated after intravenous infusion of 500 cc of normal saline in 10 minutes. An increase of at least 10% of LVOT time–velocity integral from baseline was considered as positive response to volume challenge, as stated in previous studies (1,2). Results Fluid challenge showed positive response in 7/13 patients. From ROC curve analysis an inspiratory diameter of 9,5 mm or a respiratory collapse of 52% or more both had a 75% sensitivity for volume challenge responsiveness. Conclusion Accounting for small sample size this preliminary work suggests that non invasive bedside parameters easy to evaluate can guide Paroxysmal AF management with crysalloid infusion on top of standard therapy. 1. Preau S et al Crit Care Med 2016; 45: e290–7 2. Bortolotti P et al Ann Intensive Care 2018; 8: 79

The Feasibility of Using Point-of-Care Ultrasound During Cardiac Arrest in Children: Rapid Apical Contractility Evaluation.

Resuscitation guidelines emphasize minimal interruption of compressions during cardiopulmonary resuscitation. Point-of-care ultrasound (POCUS) enables the clinician to visualize cardiac contractility and central artery pulsatility. The apical 4-chamber (A4), subxiphoid (SX), and femoral artery views may be used when defibrillator pads or active compressions preclude parasternal cardiac views. We hypothesized that clinicians can rapidly obtain interpretable POCUS views in healthy children from the A4, SX, and femoral positions. A prospective study of pediatric emergency medicine providers in an urban academic hospital was performed. Stable patients of 12 years or younger were scanned. Sonologists were each allotted 10 seconds to acquire A4, SX, and femoral views. Two attempts at each view were allowed. The primary outcome was whether cardiac and femoral artery scans were interpretable for contractility and pulsatility, respectively. The secondary outcome was whether cardiac scans were interpretable for effusion or right ventricular strain. A POCUS expert reviewed scans to confirm interpretability. Twenty-two sonologists performed a total of 50 scans on 22 patients. A view that was interpretable for contractility was obtained on the first attempt in 86% of A4 and 94% of SX scans. A femoral view that was interpretable for pulsatility was obtained on the first attempt in 74% of scans. Expert review was concordant with sonologist interpretation. Pediatric emergency medicine physicians can obtain interpretable cardiac and central artery views within 10 seconds most of the time. Point-of-care ultrasound has the potential to enhance care during pediatric resuscitation. Future studies on the impact of POCUS pulse checks in actual pediatric resuscitations should be performed.

Transsplenic Ultrasound-Guided Balloon Positioning During a Zone 1 Resuscitative Endovascular Balloon Occlusion of the Aorta: A Case Report

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is an effective resuscitative modality to temporize noncompressible truncal hemorrhage. Confirming the proper position of the balloon catheter in the target aortic zone is vital. Currently, there is a need for nonradiographical methods. This would overcome the drawbacks of conventional imaging modalities, such as fluoroscopy. Several studies have suggested ultrasound-guided visualization via subxiphoid, transperitoneal, or transesophageal views as an alternative to conventional imaging methods. However, such views are easily obscured in emergency settings. Herein, we report the case of a 70-year-old patient who was successfully resuscitated by REBOA under the guidance of transsplenic ultrasound. REBOA was safely performed using transsplenic visualization without fluoroscopy.

Development of a Consensus-Based Definition of Focused Assessment With Sonography for Trauma in Children

The wide variation in the accuracy and reliability of the Focused Assessment With Sonography for Trauma (FAST) and the extended FAST (E-FAST) for children after blunt abdominal trauma reflects user expertise. FAST and E-FAST that are performed by experts tend to be more complete, better quality, and more often clinically valuable. To develop definitions of a complete, high-quality, and accurate interpretation for the FAST and E-FAST in children with injury using an expert, consensus-based modified Delphi technique. This consensus-based qualitative study was conducted between May 1 to June 30, 2021. It used a scoping review and iterative Delphi technique and involved 2 rounds of online surveys and a live webinar to achieve consensus among a 26-member panel. This panel consisted of international experts in pediatric emergency point-of-care ultrasonography. Definitions of complete, high-quality, and accurate FAST and E-FAST studies for children after injury. Of the 29 invited pediatric FAST experts, 26 (15 men [58%]) agreed to participate in the panel. All 26 panelists completed the 2 rounds of surveys, and 24 (92%) participated in the live and asynchronous online discussions. Consensus was reached on FAST and E-FAST study definitions, and the panelists rated these 5 anatomic views as important and appropriate for a complete FAST: right upper-quadrant abdominal view, left upper-quadrant abdominal view, suprapubic views (transverse and sagittal), and subxiphoid cardiac view. For E-FAST, the same FAST anatomic views with the addition of the lung or pneumothorax view were deemed appropriate and important. In addition, the panelists rated a total of 32 landmarks as important for assessing completeness. Similarly, the panelists rated 14 statements on quality and 20 statements on accurate interpretation as appropriate. This qualitative study generated definitions for complete FAST and E-FAST studies with high image quality and accurate interpretation in children with injury. These definitions are similar to those in adults with injury and may be used for future education, quality assurance, and research. Future research may focus on interpretation of trace volumes of abdominal free fluid and the use of serial FAST.

A Multicenter, Prospective Study Comparing Subxiphoid and Parasternal Views During Brief Echocardiography: Effect on Image Quality, Acquisition Time, and Visualized Anatomy

BackgroundRecent literature has suggested echocardiography (echo) may prolong pauses in chest compressions during cardiac arrest. ObjectvesWe sought to determine the impact of the sonographic approach (subxiphoid [SX] vs. parasternal long [PSL]) on time to image completion, image quality, and visualization of cardiac anatomy during echo, as performed during Advanced Cardiac Life Support. MethodsThis was a multicenter, randomized controlled trial conducted at 29 emergency departments (EDs) assessing the time to image acquisition and image quality between SX and PSL views for echo. Patients were enrolled in the ED and imaged in a simulated cardiac arrest scenario. Clinicians experienced in echo performed both SX and PSL views, first view in random order. Image quality and time to image acquisition were recorded. Echos were evaluated for identification of cardiac landmarks. Data are presented as percentages or medians with interquartile ranges (IQRs). ResultsWe obtained 6247 echo images, comprising 3124 SX views and 3123 PSL. Overall time to image acquisition was 9.0 s (IQR 6.7–14.1 s). Image acquisition was shorter using PSL (8.8 s, IQR 6.5–13.5 s) compared with SX (9.3 s, IQR 6.7–15.0 s). The image quality was better with the PSL view (3.86 vs. 3.54; p < 0.0001), twice as many SX images scoring in the worst quality category compared with PSL (8.6% vs. 3.7%). Imaging of the pericardium, cardiac chambers, and other anatomic landmarks was superior with PSL imaging. ConclusionsEcho was performed in < 10 s in > 50% of patients using either imaging technique. Imaging using PSL demonstrated improved image quality and improved identification of cardiac landmarks.

Caudal vena cava point-of-care ultrasound in dogs with degenerative mitral valve disease without clinically important right heart disease

ObjectivesCaudal vena cava (CVC) diameter and collapsibility index (CVCD and CVCCI) have been used to assess intravascular volume status (IVS). Maladaptations with progressive degenerative mitral valve disease (DMVD) lead to hypervolemia. We hypothesised that stages of DMVD will affect ultrasonographic CVC variables in dogs without clinically important right heart disease. Animals, materials and methodsThis retrospective study included 79 dogs with DMVD presented to the cardiology department between January 2017 and 2019. Subxiphoid views were used to obtain CVC cineloops. By visual inspection, CVC was subjectively scored as flat, normal or fat. Maximal and minimal CVCD were measured and indexed to aortic diameter (CVCD-max/Ao and CVCD-min/Ao); CVCCI was calculated as (CVCD-max-CVCD-min)/CVCD-max. Fisher's exact and Kruskal–Wallis tests were used to compare CVC variables. ResultsSubjective assessment was associated with American College of Veterinary Internal Medicine (ACVIM) stages (P < 0.001). The proportion of fat CVC was greater in stages C and D. In stage D, CVCD-max/Ao was larger compared with stages B1, B2 and C (P = 0.002, P = 0.002 and P = 0.035, respectively). In stages C and D, CVCD-min/Ao was larger compared with B1 (P = 0.016 and P = 0.001) and B2 (P = 0.002 and P < 0.001. In stages C and D, CVCCI was less than stage B1 (P = 0.016 and P = 0.044) and B2 (P = 0.001 and P = 0.010). ConclusionsIn dogs with DMVD without clinically important right heart disease, CVC variables differ across ACVIM stage. Subjective and objective CVC variables may be used to predict hypervolemia.

Ultrasonographically derived caudal vena cava parameters acquired in a standing position and lateral recumbency in healthy, lightly sedated cats: a pilot study.

The aim of this study was to determine the feasibility of ultrasonographically measuring the caudal vena cava (CVC) at the subxiphoid view of healthy, lightly sedated cats in a standing position and lateral recumbency. This was a prospective, observational, experimental single-centre study. Twenty healthy research-purposed cats were enrolled. Two trained operators scanned each cat in two positions - standing and lateral recumbency - in a randomised order. CVC diameter was measured at the narrowest diameter during inspiration and at the widest diameter during expiration, at two anatomical locations along the CVC - where the CVC crosses the diaphragm (base) and 2 mm caudal to the diaphragm. The CVC collapsibility index (CVC-CI) was calculated for each site. Normalcy was assessed with a Shapiro-Wilk test. A one-way ANOVA with post-hoc Tukey's test was used to compare inspiratory with expiratory values within and between groups. A paired t-test compared the CVC-CI between groups (P ⩽0.05 indicated statistical significance). Spearman's correlation and Bland-Altman analysis assessed inter-operator variability. All ultrasonographic data passed normalcy and were reported as mean ± SD. When compared with each other, inspiratory and expiratory values were statistically different for position, location and operator (all P <0.0001). There was no statistically significant difference between lateral recumbency or standing position for inspiratory, expiratory and CVC-CI values. Inter-operator variability was substantial, with operator 2 consistently obtaining smaller measurements than operator 1. The mean CVC-CI in lateral recumbency at the base was 24% for operator 1 and 37% for operator 2. For the same site in standing position, CVC-CI was 27% and 41% for operators 1 and 2, respectively. This pilot study demonstrates that it is possible to ultrasonographically measure the CVC diameter in both lateral recumbency and a standing position in healthy, lightly sedated cats. However, measurements obtained are operator dependent with variability between individuals. Further studies are needed to determine if ultrasonographic CVC assessment will prove helpful in estimating intravascular volume status in cats.

Measurement of Caval Aorta Diameter Index by Transthoracic Echocardiogram in Normal Indian Population

Background: Bedside ultrasonography is a promising noninvasive and rapid technique to assess body fluid status. Early detection of hypovolemia and hypervolemia is crucial to guide management in critically ill patients. There is a considerable demographic variability in the normal range of inferior vena cava dimensions as seen in numerous studies and a steadfast formula to calculate caval diameter based on demographic parameters and body growth is not available till date. Caval aorta diameter index had a positive correlation with invasively measured central venous pressure as established by previous studies done in intensive care units. The simplicity of examination technique makes this index useful in every situation where body fluid status has therapeutic and prognostic implications. This study aims to identify standard normal measurement of caval aorta index by easily available two-dimensional echocardiography in subcostal view and by right coronal approach/transhepatic view in different age groups in Indian patients. Materials and Methods: One hundred and two patients referred for routine cardiac status evaluation who were asymptomatic and clinically normal without any major medical illness with normal echocardiogram were prospectively analyzed and caval aorta index assessed in both subxiphoid and transhepatic right coronal view. Results: Normal caval aorta index measured in subcostal view was 1.108 ± 0.076 and measured in transhepatic view was 1.101 ± 0.082 (mean ± 2 standard deviation). The difference of caval aorta index measured in both views was not significant statistically (P = 0.207). Conclusion: In this study, we provide a normal reference level for sonographic caval aorta index in Indian population measured in subxiphoid and transhepatic views. We also conclude that transhepatic right coronal view measurements for this index are comparable to subcostal view, so both views can be used alternatively when one window is suboptimal.

Ultrasound assessment of the inferior vena cava in children: A comparison of sub-xiphoid and right lateral coronal views.

The inferior vena cava collapsibility index (IVCCI) has been used to assess the respiratory variation of the inferior vena cava (IVC) diameter and hence intravascular volume. The sub-xiphoid view (SXV) is the standard view to evaluate the IVC. The right lateral transabdominal view (RLV) has been shown in adults to be an alternative view to evaluate the IVC when the SXV is not feasible. The aim of the study was to compare IVC dimensions from these two views and thus determine whether the RLV view can be used instead of the SXV in pediatric patients. We conducted a single-center prospective observational crossover study. Study subjects were ASA physical status 1-2 children, 1-12 years of age scheduled for elective surgery under general anesthesia. Anesthesia was maintained by mask with spontaneous ventilation with end-tidal sevoflurane at 2%-5% after the induction of anesthesia. IVCCI was measured using M-mode in both the SXV and RLV. The study cohort included 50 children with a mean age of 5.1 years. The median value for the IVCCI-sx was 0.45 (IQR: 0.28-0.70) while the IVCCI-rl was 0.30 (0.19-0.5). The mean difference between the two groups was 0.12 (95% CI: 0.177-0.066, p < .001, two-tailed paired t-test). Spearman's rank correlation coefficient was 0.66. The univariate linear regression model was IVCCIsx=0.21 + 0.77 × IVCCIrl. IVCCIrl was lower than IVCCIsx. IVCCI measured from the right lateral view tended to overestimate the patient's fluid-responsiveness and therefore these two values are not interchangeable.

Ultrasonographic assessment of the caudal vena cava diameter in cats during blood donation.

ObjectivesUltrasonography of the caudal vena cava (CVC) has been previously established to assess fluid status in dogs but not in cats. The aim of this study was to determine CVC diameter changes during feline blood donation.MethodsInter- and intra-observer variability were assessed in 11 client-owned cats. Minimal and maximal CVC diameters were assessed longitudinally in the subxiphoid view (SV) and right paralumbar view (PV), and transversely in the right hepatic intercostal view (HV). Eighteen client-owned, healthy, anaesthetised cats were evaluated during 21 blood donation procedures of 10 ml/kg in the same anatomical locations before (T0) and after (T1) blood donation, and after volume resuscitation with 30 ml/kg lactated Ringer’s solution (T2). The CVC index was calculated.ResultsIntra-observer variability was acceptable for all probe positions, except for the HV, whereas inter-observer variability was considered unacceptable for all probe positions. Complete measurements were obtained during 21 blood donations at T0, T1 and T2 at the SV, during 18/21 blood donations at the HV and during 16/21 blood donations at the PV. At the SV, the minimal CVC diameter between T1 and T2 (P <0.001), and the maximal CVC diameter between T0 and T1 and between T1 and T2 (P <0.001) were significantly different. At the HV, the minimal vertical diameter, maximal vertical diameter and minimal horizontal diameter were different between all timepoints (P <0.001). The maximal horizontal diameter was different between T1 and T2 (P = 0.002). At the PV, both diameters were different between all timepoints (P <0.001). The CVC index was not different between timepoints.Conclusion and relevanceSignificant probe position dependent CVC diameter changes with marked overlap were observed before and after blood donation, and after fluid bolus. No absolute CVC diameter could be used to indicate hypovolaemia. Ultrasonographic assessment of the feline CVC is highly operator-dependent. The CVC index is not useful in cats.

Point-of-care ultrasound during the COVID-19 pandemic: A multidisciplinary approach between intensivists and echocardiographers.

PurposeThe coronavirus disease‐2019 (COVID‐19) led to a large influx of critically ill patients and altered echocardiography laboratory workflow. We developed a point‐of‐care ultrasound (POCUS) first approach to patients requiring echocardiography and describe our workflow and findings.MethodsWe performed a single‐center retrospective analysis of all POCUS studies performed on critically ill patients with COVID‐19. Sonography was performed by intensivists, uploaded and archived, and rapidly reviewed by echocardiographers. We evaluated each study based on the number of views obtained. Additionally, we provide a description of the workflow during the COVID‐19 surge at a tertiary care hospital in New York City.ResultsFifty patients had POCUS studies performed by intensivists and reviewed by echocardiographers obviating the need for sonographer‐performed studies. Of the 48 cardiac POCUS studies, 17% of patients had 4 of 4 standard views available while 53% had 3 of 4 standard views. The parasternal long‐axis view was obtained on 81%, subxiphoid view on 79%, apical 4‐chamber view on 71%, and parasternal short‐axis view on 63% of patients.ConclusionsOur POCUS workflow allowed intensivists to perform cardiac sonography for rapid bedside diagnosis of pathology with immediate interpretation performed by echocardiographers. At least 3 views were obtained in the majority of cases.

What is the ideal approach for emergent pericardiocentesis using point-of-care ultrasound guidance?

Traditionally performed using a subxiphoid approach, the increasing use of point-of-care ultrasound in the emergency department has made other approaches (parasternal and apical) for pericardiocentesis viable. The aim of this study is to identify the ideal approach for emergency-physician-performed ultrasound-guided pericardiocentesis as determined by ultrasound image quality, distance from surface to pericardial fluid, and likely obstructions or complications. A retrospective review of point-of-care cardiac ultrasound examinations was performed in two urban academic emergency departments for the presence of pericardial effusions. The images were reviewed for technical quality, distance of effusion from skin surface, and predicted complications. A total of 166 pericardial effusions were identified during the study period. The mean skin-to-pericardial fluid distance was 5.6 cm (95% confidence interval [95% CI] 5.2-6.0 cm) for the subxiphoid views, which was significantly greater than that for the parasternal (2.7 cm [95% CI 2.5-2.8 cm], P<0.001) and apical (2.5 cm [95% CI 2.3-2.7 cm], P<0.001) views. The subxiphoid view had the highest predicted complication rate at 79.7% (95% CI 71.5%-86.4%), which was significantly greater than the apical (31.9%; 95% CI 21.4%-44.0%, P<0.001) and parasternal (20.2%; 95% CI 12.8%-29.5%, P<0.001) views. Our results suggest that complication rates with pericardiocentesis will be lower via the parasternal or apical approach compared to the subxiphoid approach. The distance from skin to fluid collection is the least in both of these views.

Prevalence of congenital cardiac tumours in 25,000 neonates

Abstract Background Primary cardiac tumours in children are rare, with an estimated prevalence of 0.014% in foetuses, whereas in the paediatric population, a 100-fold difference in autopsy prevalence has been reported (0.0017% to 0.28%). In neonates, rhabdomyoma is the most common primary cardiac tumour, followed by teratoma and fibroma, all of which are benign. Cardiac rhabdomyomas are associated to tuberous sclerosis in &amp;gt;50% of cases. The prevalence of cardiac tumours in neonates has not previously been assessed in a large population-based cohort. Purpose To determine the prevalence of congenital cardiac tumours by systematic echocardiography in a large, population-based, cohort of neonates. Methods Systematic transthoracic echocardiography (TTE), including standard sub-xiphoid, apical, left parasternal, and suprasternal views, was performed in neonates included in a population study. Cardiac tumours were defined as solid, echogenic masses, and description included location, size, and numbers (one/multiple). Information regarding subsequent diagnosis of tuberous sclerosis was collected from review of medical charts. Results A total of 25,537 neonates (age 12±9 days, 51.6% male) were enrolled in the study and underwent TTE. Cardiac tumours were detected in 7 neonates (4 males), corresponding to a prevalence of 0.3 [0.1; 0.6] per 1,000 live-births. Characteristics including sex, gestational age at birth, birth length and weight, APGAR 5-score, age and weight at TTE, and maternal age and pre-pregnancy BMI, did not significantly differ between the neonates with (n=7) and without (n=25,530) cardiac tumours (all p&amp;gt;0.05). In 6 out of 7 neonates, the cardiac tumours were located in the ventricles (86%), with multiple tumours seen in five (83%) (Fig. 1A+B), and with size ranging from 2.0x1.9mm to 10.0x5.1mm. In the seventh neonate, two cardiac tumours were detected in close proximity to the aortic and pulmonary valves in the ascending aortic and main pulmonary artery wall (Fig. 1C), with sizes 5.1x4.7mm and 3.7x3.2mm, respectively. All seven neonates had otherwise structurally normal hearts and no flow obstruction. Three neonates with multiple cardiac tumours in the ventricles were subsequently diagnosed with tuberous sclerosis. Conclusions Systematic TTE in a population-based cohort revealed a prevalence of congenital cardiac tumours of 0.3 per 1,000 live-births. The majority of the tumours were located in the ventricles and most often multiple cardiac tumours were encountered. Detection of congenital cardiac tumours in the ventricles was associated with tuberous sclerosis in half the cases. Funding Acknowledgement Type of funding source: Foundation. Main funding source(s): Danish Heart Association, Danish Children's Heart Foundation