Diagnostic Accuracy of Point-of-Care Ultrasound Performed by Pulmonary Critical Care Physicians for Right Ventricle Assessment in Patients With Acute Pulmonary Embolism

New Diagnostic Tools for Pulmonary Embolism Detection

The presentation of pulmonary embolism (PE) varies from asymptomatic to life-threatening, and management involves multiple specialists. Timely diagnosis of PE is based on clinical presentation, D-dimer testing, and computed tomography pulmonary angiogram (CTPA), and assessment by a Pulmonary Embolism Response Team (PERT) is critical to management. Artificial intelligence (AI) technology plays a key role in the PE workflow with automated detection and flagging of suspected PE in CTPA imaging. HIPAA-compliant communication features of mobile and web-based applications may facilitate PERT workflow with immediate access to imaging, team activation, and real-time information sharing and collaboration. In this review, we describe contemporary diagnostic tools, specifically AI, that are important in the triage and diagnosis of PE.

Defining Intensivists: A Retrospective Analysis of the Published Studies in the United States, 2010-2020

OBJECTIVES

The Society of Critical Care Medicine last published an intensivist definition in 1992. Subsequently, there have been many publications relating to intensivists. Our purpose is to assess how contemporary studies define intensivist physicians.

DESIGN

Systematic search of PubMed, Embase, and Web of Science (2010-2020) for publication titles with the terms intensivist, and critical care or intensive care physician, specialist, or consultant. We included studies focusing on adult U.S. intensivists and excluded non-data-driven reports, non-U.S. publications, and pediatric or neonatal ICU reports. We aggregated the study title intensivist nomenclatures and parsed Introduction and Method sections to discern the text used to define intensivists. Fourteen parameters were found and grouped into five definitional categories: A) No definition, B) Background training and certification, C) Works in ICU, D) Staffing, and E) Database related. Each study was re-evaluated against these parameters and grouped into three definitional classes (single, multiple, or no definition). The prevalence of each parameter is compared between groups using Fisher exact test.

SETTING

U.S. adult ICUs and databases.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Of 657 studies, 105 (16%) met inclusion criteria. Within the study titles, 17 phrases were used to describe an intensivist; these were categorized as intensivist in 61 titles (58%), specialty intensivist in 30 titles (29%), and ICU/critical care physician in 14 titles (13%). Thirty-one studies (30%) used a single parameter (B-E) as their definition, 63 studies (60%) used more than one parameter (B-E) as their definition, and 11 studies (10%) had no definition (A). The most common parameter "Works in ICU" (C) in 52 studies (50%) was more likely to be used in conjunction with other parameters rather than as a standalone parameter (multiple parameters vs single-parameter studies; 73% vs 17%; p < 0.0001).

CONCLUSIONS

There was no consistency of intensivist nomenclature or definitions in contemporary adult intensivist studies in the United States.

Pulmonary artery diameter correlates with echocardiographic parameters of right ventricular dysfunction in patients with acute pulmonary embolism

Introduction

Right ventricular dysfunction (RVD) is a key component in the process of risk stratification in patients with acute pulmonary embolism (PE). Echocardiography remains the gold standard for RVD assessment, however, measures of RVD may be seen on CTPA imaging, including increased pulmonary artery diameter (PAD). The aim of our study was to evaluate the association between PAD and echocardiographic parameters of RVD in patients with acute PE.

Methods

Retrospective analysis of patients diagnosed with acute PE was conducted at large academic center with an established pulmonary embolism response team (PERT). Patients with available clinical, imaging, and echocardiographic data were included. PAD was compared to echocardiographic markers of RVD. Statistical analysis was performed using the Student's t test, Chi-square test, or one-way analysis of variance (ANOVA); P < 0.05 was considered statistically significant.

Results

270 patients with acute PE were identified. Patients with a PAD >30 mm measured on CTPA had higher rates of RV dilation (73.1% vs 48.7%, P < 0.005), RV systolic dysfunction (65.4% vs 43.7%, P < 0.005), and RVSP >30 mmHg (90.2% vs 68%, P = 0.004), but not TAPSE ≤1.6 cm (39.1% vs 26.1%, P = 0.086). A weak increasing linear relationship between PAD and RVSP was noted (r = 0.379, P = 0.001).

Conclusions

Increased PAD in patients with acute PE was significantly associated with echocardiographic markers of RVD. Increased PAD on CTPA in acute PE can serve as a rapid prognostic tool and assist with PE risk stratification at the time of diagnosis, allowing rapid mobilization of a PERT team and appropriate resource utilization.

Right ventricular echocardiographic parameters and prediction of stroke volume in ischemic cardiogenic shock: A retrospective study

PURPOSE

This study investigated which commonly used right ventricular (RV) echocardiographic parameter correlates best with stroke volume (SV) estimated by Doppler echocardiography in ischemic cardiogenic shock (CS).

MATERIALS AND METHODS

We retrospectively reviewed the records of 100 patients admitted to the ICU over 34 months with CS. Tricuspid annular plane systolic excursion (TAPSE), Tricuspid annulus systolic velocity (RV S'), Tricuspid regurgitation maximum velocity (TR Vmax), and RV outflow tract velocity time integral (RVOT VTI) were correlated to SV.

RESULTS

Mean age was 62.6 ± 12.7 years and 78% were male. The mean SV, TAPSE, RV S', TR Vmax, and RVOT VTI were 47 ± 16 ml, 16 ± 5 mm, 11 ± 4 mm/s, 1.97 ± 0.73 m/s, and 12.7 ± 5 cm, respectively. RVOT VTI correlated best to SV (r = 0.39 p = 0.01) compared to TAPSE, RV S', and TR Vmax (r = 0.26 p = 0.01, r = 0.15 p = 0.21, r = 0.03 p = 0.78). RVOT VTI independently predicted SV. Univariate analysis demonstrated that only RVOT VTI predicted SV (OD = 1.18 p = 0.04) and had the best area under the curve (0.70, p = 0.03).

CONCLUSION

RVOT VTI correlated better (albeit weakly) to and best predicted SV compared to TAPSE, RV S', and TR Vmax in patients admitted to intensive care with CS. This study suggests that RVOT VTI has the potential as a therapeutic target to optimize SV in CS.

The Use of POCUS to Manage ICU Patients With COVID-19

Since the advent of SARS-CoV-2, the virus that causes COVID-19, clinicians have had to modify how they provide high-value care while mitigating the risk of viral spread. Routine imaging studies have been discouraged due to elevated transmission risk. Patients who have been diagnosed with COVID-19 often have a protracted hospital course with progression of disease. Given the need for close follow-up of patients, we recommend the use of ultrasonography, particularly point-of-care ultrasound (POCUS), to manage patients with COVID-19 through their entire ICU course. POCUS will allow a clinician to evaluate and monitor cardiac and pulmonary function, as well as evaluate for thromboembolic disease, place an endotracheal tube, confirm central venous catheter placement, and rule out a pneumothorax. If a patient improves sufficiently to perform weaning trials, POCUS can also help evaluate readiness for ventilator liberation.

Critical Care Echocardiography: A Primer for the Nephrologist

Critical care echocardiography (CCE) refers to the goal-directed use of transthoracic or transesophageal echocardiography and represents one of the most common applications of critical care ultrasound. CCE can be performed at the point of care, is easily repeated following changes in clinical status, and does not expose the patient to ionizing radiation. Nephrologists who participate in the care of patients in the intensive care unit will regularly encounter CCE as part of the decision-making and bedside management of ICU patients. The four primary indications for CCE are the characterization of shock, evaluation of preload tolerance, evaluation of volume responsiveness, and serial hemodynamic assessment to evaluate response to therapeutic interventions. This article provides an overview of the anatomical structures that are routinely assessed in basic CCE, describes how these findings are incorporated into the clinical assessment of critically ill patients, and introduces some common applications of advanced CCE.

Prevention, diagnosis, and management of venous thromboembolism in the critically ill surgical and trauma patient

PURPOSE OF REVIEW

Venous thromboembolism (VTE), which encompasses deep vein thrombosis and pulmonary embolism, is common among trauma patients and critically ill surgical patients admitted to the ICU. Critical care surgical patients are at an extremely high risk for VTE and the related morbidity and mortality associated with it. The present review aims to provide an overview of the importance of identifying risk factors, prescribing effective prohylaxis, accurate diagnosis, and timely appropriate treatment for trauma and critically ill surgical patients with VTE in the ICU.

RECENT FINDINGS

VTE is a healthcare burden among critically ill surgical patients that is mostly preventable through adherence to prophylactic protocols that aim to recognize VTE risk factors while simultaneously providing guidance to appropriate timing and administration prophylaxis regimens. Newer pharmacologic therapies for prophylaxis and treatment, diagnostic modalities, and indications for therapy of VTE have continued to evolve.

SUMMARY

Critical care surgical and trauma patients represent a population that are at a heightened risk for VTE and associated complications. Appropriate screening, prevention strategies, accurate diagnosis, and timely administration of appropriate treatment must be utilized to reduce morbidity and mortality.

Visual Estimation of Tricuspid Annular Plane Systolic Excursion by Emergency Medicine Clinicians

INTRODUCTION

Tricuspid annular plane systolic excursion (TAPSE) is an established echocardiographic marker of right ventricular (RV) systolic function. The objective of this study was to evaluate whether emergency clinicians can visually estimate RV function using TAPSE in a set of video clips compared to a reference standard M-mode measurement.

METHODS

Emergency clinicians were shown a five-minute educational video on TAPSE. Participants then viewed 20 apical four-chamber point-of-care ultrasound (POCUS) echocardiography clips and recorded their estimate of TAPSE distance in centimeters (cm), as well as whether TAPSE was normal (>1.9 cm), borderline (1.5-1.9 cm), or abnormal (<1.5 cm). We calculated sensitivity, specificity, and overall accuracy of visual TAPSE categorization using M-mode measurement as the criterion standard. Participants also reported their comfort with assessing TAPSE on a five-point Likert scale before and after participation in the study.

RESULTS

Among 70 emergency clinicians, including 20 postgraduate year 1-4 residents, 22 attending physicians, and 28 physician assistants (PA), the pooled sensitivity and specificity for visual assessment of TAPSE was 88.6% (95% confidence interval, 85.4-91.7%) and 81.6% (95% CI, 78.2-84.4%), respectively. The sensitivity and specificity for the clips in which the measured TAPSE was <1.5 cm or >1.9 cm was 91.4% (95% CI, 88.4-94.3%) and 90.8% (95% CI, 87.7-93.9%), respectively. There was no significant difference in sensitivity (p = 0.27) or specificity (p = 0.55) between resident and attending physicians or between physicians and PAs (p = 0.17 and p = 0.81). Median self-reported comfort with TAPSE assessment increased from 1 (interquartile range [IQR] 1-2) to 3 (IQR 3-4) points after participation in the study.

CONCLUSION

A wide range of emergency clinicians demonstrated fair accuracy for visual estimation of TAPSE on previously recorded POCUS echocardiography video clips. These findings should be considered hypothesis generating and warrant validation in larger, prospective studies.

Ultrasound measurement of laryngeal structures in the parasagittal plane for the prediction of difficult laryngoscopies in Chinese adults

Background

Abnormal laryngeal structures are likely to be associated with a difficult laryngoscopy procedure. Currently, laryngeal structures can be measured by ultrasonography, however, little research has been performed on the potential role of ultrasound on the evaluation of a difficult laryngoscopy. The present study investigated the value of laryngeal structure measurements for predicting a difficult laryngoscopy.

Objective

The main objective of this study was to explore the value of laryngeal structure measurements for predicting a difficult laryngoscopy.

Methods

Two hundred and eleven adult patients (over 18 years old) were recruited to undergo elective surgery under general anesthesia via endotracheal intubation. Ultrasound was utilized to measure the distance between the skin and thyroid cartilage (DST), the distance between the thyroid cartilage and epiglottis (DTE), and the distance between the skin and epiglottis (DSE) in the parasagittal plane. These metrics were then investigated as predictors for classifying a laryngoscopy as difficult vs easy, as defined by the Cormack and Lehane grading scale.

Results

Multivariate logistic regression showed that the DSE, but not DST or DTE, was significantly related to difficult laryngoscopies. Specifically, a DSE ≥ 2.36 cm predicted difficult laryngoscopies with a sensitivity and specificity of 0.818 (95% CI: 0.766–0.870) and 0.856 (95% CI: 0.809–0.904). Furthermore, when combining the best model constructed of other indicators (i.e. sex, body mass index, modified Mallampati test) to predict the difficult laryngoscopy, the AUC reached 93.28%.

Conclusion

DSE is an independent predictor of a difficult laryngoscopy; a DSE cutoff value of 2.36 cm is a better predictor of a difficult laryngoscope than other ultrasound or physiological measurements for predicting a difficult laryngoscope. Nevertheless, it’s more valuable to apply the best model of this study, composed of various physiological measurements, for this prediction purpose.

Impact of goal directed basic echocardiography on diagnostic and therapeutic management in an ICU of cardiac surgery

OBJECTIVE

Few studies have evaluated the impact in diagnosis and therapeutic management of basic transthoracic echocardiography in postoperated cardiac surgery. The aim of our study was to evaluate the impact of basic transthoracic echocardiography in the management of this kind of patients.

DESIGN

Over an 18-month period, we prospectively studied all patients admitted to a university hospital Intensive Care Unit following heart surgery. We evaluated clinically all of them to establish a diagnosis and an initial treatment. We performed basic transthoracic echocardiography for a diagnosis evaluation that was compared with clinical diagnosis. If they differed, we assessed to change treatment and evaluate the therapeutic response. We performed a descriptive analysis.

RESULTS

We included 136 patients and performed 203 echocardiographies. Transthoracic echocardiography differed of initial diagnosis in 101 (49.8%) echocardiographies. In 56 of these echocardiographies (55.44%), we could give an alternative diagnosis with a change in the treatment in 30patients (53,6%). We found clinical improvement in 26 patients (86.76%) in the following 30-60minutes.

CONCLUSIONS

Basic transthoracic echocardiography is useful in diagnostic and therapeutic management of postoperative cardiac surgery patients. We could not confirm the clinical diagnosis in half of the performed echocardiographies. In most patients in whom we observe a change in the diagnosis due to echocardiography, we observed a clinical improvement after changing the treatment.

Role of echocardiography in managing acute pulmonary embolism

The role of echocardiography in acute pulmonary embolism (PE) remains incompletely defined. Echocardiography cannot reliably diagnose acute PE, and it does not improve prognostication of patients with low-risk acute PE who lack other clinical features of right ventricular (RV) dysfunction. Echocardiography, however, may yield additional prognostic information in higher risk patients and can aid in distinguishing acute from chronic RV dysfunction. Specific echocardiographic markers of RV dysfunction have the potential to enhance prognostication beyond existing risk models. Until these markers are subjected to rigorous prospective studies, the therapeutic utility and economic value of echocardiography in acute PE are uncertain.