Guidelines for the Appropriate Use of Bedside General and Cardiac Ultrasonography in the Evaluation of Critically Ill Patients—Part II: Cardiac Ultrasonography

Critical Care Management of the Patient with Pulmonary Hypertension

Pulmonary hypertension patients admitted to the intensive care unit have high mortality, and right ventricular failure typically is implicated as cause of or contributor to death. Initial care of critically ill pulmonary hypertension patients includes recognition of right ventricular failure, appropriate monitoring, and identification and treatment of any inciting cause. Management centers around optimization of cardiac function, with a multipronged approach aimed at reversing the pathophysiology of right ventricular failure. For patients who remain critically ill or in shock despite medical optimization, mechanical circulatory support can be used as a bridge to recovery or lung transplantation.

A Call to Action for the Pediatric Critical Care Community

Healthcare regulatory bodies have escalated concerns regarding the use of point-of-care ultrasound by nonradiology and noncardiology physicians. A recently published PCCMPerspective identified that data do not support many of these concerns and addressed common misconceptions associated with point-of-care ultrasound use in the critical care setting. Indeed, the global point-of-care ultrasound community and specifically the pediatric critical care community have the opportunity to be leaders in demonstrating how to translate new skills and technologies to the bedside in a safe and effective manner. We seek to extend the conversation and propose next steps in supporting integration of point-of-care ultrasound in pediatric critical care practice.

Procedural Applications of Point-of-Care Ultrasound in Pediatric Emergency Medicine

Point-of-care ultrasound can improve efficacy and safety of pediatric procedures performed in the emergency department. This article reviews ultrasound guidance for the following pediatric emergency medicine procedures: soft tissue (abscess incision and drainage, foreign body identification and removal, and peritonsillar abscess drainage), musculoskeletal and neurologic (hip arthrocentesis, peripheral nerve blocks, and lumbar puncture), vascular access (peripheral intravenous access and central line placement), and critical care (endotracheal tube placement, pericardiocentesis, thoracentesis, and paracentesis). By incorporating ultrasound, emergency physicians caring for pediatric patients have the potential to enhance their procedural scope, confidence, safety, and success.

Tube-load model: A clinically applicable pulse contour analysis method for estimation of cardiac stroke volume

BACKGROUND AND OBJECTIVES

Accurate, reproducible, and reliable real-time clinical measurement of stroke volume (SV) is challenging. To accurately estimate arterial mechanics and SV by pulse contour analysis, accounting for wave reflection, such as by a tube-load model, is potentially important. This study tests for the first time whether a dynamically identified tube-load model, given a single peripheral arterial input signal and pulse transit time (PTT), provides accurate SV estimates during hemodynamic instability.

METHODS

The model is tested for 5 pigs during hemodynamic interventions, using either an aortic flow probe or admittance catheter for a validation SV measure. Performance is assessed using Bland-Altman and polar plot analysis for a series of long-term state-change and short-term dynamic events.

RESULTS

The overall median bias and limits of agreement (2.5th, 97.5th percentile) from Bland-Altman analysis were -10% [-49, 36], and -1% [-28,20] for state-change and dynamic events, respectively. The angular limit of agreement (maximum of 2.5th, 97.5th percentile) from polar-plot analysis for state-change and dynamic interventions was 35.6^∘, and 35.2^∘, respectively.

CONCLUSION

SV estimation agreement and trending performance was reasonable given the severity of the interventions. This simple yet robust method has potential to track SV within acceptable limits during hemodynamic instability in critically ill patients, provided a sufficiently accurate PTT measure.

Utilization of Echocardiography After Acute Kidney Injury Was Associated with Improved Outcomes in Patients in Intensive Care Unit

Background

We aimed to investigate the association between usage of transthoracic echocardiography (TTE) within 24 hours after acute kidney injury (AKI) and the prognosis of patients in intensive care unit (ICU).

Methods

The Medical Information Mart for Intensive Care III (MIMIC-III) database was used to identify AKI patients with and without TTE administration. The primary outcome was 28-day mortality. Multivariable regression was used to clarify the association between TTE and clinical outcomes and propensity score matching (PSM) and inverse probability of treatment weighting (IPTW) were utilized to validate our findings.

Results

Among 23,945 eligible AKI patients, 3361 patients who received TTE and 3361 who did not conduct TTE had similar propensity scores which were included in this study. After matching, the TTE group had a significantly lower 28-day mortality (OR 0.80, 95% CI 0.72–0.88, P<0.001). Patients in the TTE group received more fluid on day 1 and day 2 and had a more urine volume on day 1 and day 3, and the reduction in serum creatinine was greater than that in the no TTE group. The mediating effect of creatinine reduction was remarkable for the whole cohort (P=0.02 for the average causal mediation effect).

Conclusion

TTE utilization was associated with decreased risk-adjusted 28-day mortality for AKI patients in ICU and was proportionally mediated through creatinine reduction.

Focused echocardiography, end-tidal carbon dioxide, arterial blood pressure or near-infrared spectroscopy monitoring during paediatric cardiopulmonary resuscitation: A scoping review

AIM

To evaluate the individual use and predictive value of focused echocardiography, end-tidal carbon dioxide (EtCO2), invasive arterial blood pressure (BP) and near-infrared spectroscopy (NIRS) during cardiopulmonary resuscitation (CPR) in children.

METHODS

This scoping review was undertaken as part of the continuous evidence evaluation process of the International Liaison Committee on Resuscitation (ILCOR) and based on the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) extension for scoping reviews. PubMed, MEDLINE, CINAHL and EMBASE were searched from the last ILCOR reviews until September 2020. We included all published studies evaluating the effect of echocardiography, EtCO2, BP or NIRS guided CPR on clinical outcomes and quality of CPR.

RESULTS

We identified eight observational studies, including 288 children. Two case series reported the use of echocardiography, one in detecting pulmonary emboli, the second in cardiac standstill, where contractility was regained with the use of extracorporeal membrane oxygenation. The two studies describing EtCO2 were ambivalent regarding the association between mean values and any outcomes. Mean diastolic BP was associated with increased survival and favourable neurological outcome, but not with new substantive morbidity in two studies describing an overlapping population. NIRS values reflected changes in EtCO2 and cerebral blood volume index in two studies, with lower values in patients who did not achieve return of circulation.

CONCLUSION

Although there seems some beneficial effect of these intra-arrest variables, higher quality paediatric studies are needed to evaluate whether echocardiography, EtCO2, BP or NIRS guided CPR could improve outcomes.

Fuzzy model based on local injection of MTX combined with traditional Chinese medicine guided by ultrasound intervention to treat CSP

In view of pregnancy at the uterine scar after cesarean section, there is an urgent need to find a conservative treatment mode with drugs that can improve the success rate of treatment, shorten the conservative treatment time, and cause little harm to the body. This research combines ultrasound intervention technology to construct a fuzzy model to comprehensively evaluate the clinical effects of traditional Chinese medicine combined with western medicine in the treatment of CSP. Moreover, this research combines the current application algorithms of machine vision to explain the relevant principles of ultrasound interventional vision. In addition, this research uses the background subtraction method to extract the target, and uses the machine vision algorithm to extract the ultrasonic detection target object. Finally, this research adjusts the control parameters according to the fuzzy control, and outputs the optimal control plan with BP network training. The results of this study show that the combination of Chinese and Western medicines in the treatment of uterine scars after cesarean section has the advantages of small gestational sacs, short pregnancy, and low blood β-HCG, and it has the advantages of less pain, economy, fewer side effects, and successfully preserves the uterus. Therefore, it is worthy of clinical application.

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.

Diagnostic Point-of-Care Ultrasound: Recommendations From an Expert Panel

Diagnostic point-of-care ultrasound (PoCUS) has emerged as a powerful tool to help anesthesiologists guide patient care in both the perioperative setting and the subspecialty arenas. Although anesthesiologists can turn to guideline statements pertaining to other aspects of ultrasound use, to date there remains little in the way of published guidance regarding diagnostic PoCUS. To this end, in 2018, the American Society of Anesthesiologists chartered an ad hoc committee consisting of 23 American Society of Anesthesiologists members to provide recommendations on this topic. The ad hoc committee convened and developed a committee work product. This work product was updated in 2021 by an expert panel of the ad hoc committee to produce the document presented herein. The document, which represents the consensus opinion of a group of practicing anesthesiologists with established expertise in diagnostic ultrasound, addresses the following issues: (1) affirms the practice of diagnostic PoCUS by adequately trained anesthesiologists, (2) identifies the scope of practice of diagnostic PoCUS relevant to anesthesiologists, (3) suggests the minimum level of training needed to achieve competence, (4) provides recommendations for how diagnostic PoCUS can be used safely and ethically, and (5) provides broad guidance about diagnostic ultrasound billing.

Respiratory variability of inferior vena cava at different mechanical ventilator settings

BACKGROUND

Assessment of the respiratory changes of the inferior vena cava (IVC) diameter have been investigated as a reliable tool to estimate the volume status in mechanically ventilated and spontaneously breathing patients. Our purpose was to compare the echocardiographic measurements the IVC diameter, stroke volume and cardiac output in different positive pressure ventilation parameters.

METHODS

This prospective clinical study with crossover design was conducted in the Intensive Care Unit (ICU). Twenty-five sedated, paralyzed, intubated, and mechanically ventilated patients with volume control mode (CMV) in the ICU due to respiratory failure were included in the study. Positive End-Expiratory Pressure (PEEP) and Tidal Volume (TV) were changed in each patient consecutively (Group A: TV 6 ml/kg, PEEP 5 cmH20, B: TV 6, PEEP 8, C: TV 8, PEEP 5, D: TV 8, PEEP 8) and the changes in vital parameters, central venous pressure (CVP) and ultrasonographic changes in IVC and cardiac parameters were measured. All measures were compared between groups by robust repeated measures ANOVA with trimmed mean.

RESULTS

The respiratory changes of the IVC diameter and echocardiographic parameters showed no significant difference in separate mechanical ventilator settings. Significant difference was found in peak and plateau pressure values among groups (p < 0.05).

CONCLUSION

The results of our study suggest that IVC related parameters are not affected with different ventilatory settings. Further studies are needed to confirm the reliability of these parameters as a predictor of fluid assessment.

Regulating Critical Care Ultrasound, It Is All in the Interpretation

Point-of-care ultrasound (POCUS) use is rapidly expanding as a practice in adult and pediatric critical care environments. In January 2020, the Joint Commission endorsed a statement from the Emergency Care Research Institute citing point-of-care ultrasound as a potential hazard to patients for reasons related to training and skill verification, oversight of use, and recordkeeping and accountability mechanisms for clinical use; however, no evidence was presented to support these concerns. Existing data on point-of-care ultrasound practices in pediatric critical care settings verify that point-of-care ultrasound use continues to increase, and contrary to the concerns raised, resources are becoming increasingly available for point-of-care ultrasound use. Many institutions have recognized a successful approach to addressing these concerns that can be achieved through multispecialty collaborations.

Assessment of lung ultrasound for early detection of respiratory complications in thoracic surgery

BACKGROUND AND OBJECTIVES

To assess lung ultrasound for the diagnosis and monitoring of respiratory complications in thoracic surgery.

METHODS

Prospective observational study in a University hospital, single institution. Adult patients scheduled for pulmonary resection surgery excluding pneumonectomy. An ultrasound follow-up was performed from the day before the surgery to the third day after surgery with calculation of B-line and lung score (reaeration and loss of aeration scores). Respiratory complications were collected throughout the hospitalization period.

RESULTS

Fifty-six patients were included. Eighteen patients presented a respiratory complication (32%), and they presented significantly higher BMI and ASA scores. Patients operated by videothoracoscopy were less at risk of complications. At day 3, a reaeration score ≤ 2 on the ventilated side or ≤ -2 on the operated side, and a B-line score>6 on the operated side were in favor of a complication.

CONCLUSION

Lung ultrasound can help in the diagnosis of respiratory complications following pulmonary resection surgery.

Assessing Competence in Critical Care Echocardiography: Development and Initial Results of an Examination and Certification Processes

OBJECTIVES

To describe the development and initial results of an examination and certification process assessing competence in critical care echocardiography.

DESIGN

A test writing committee of content experts from eight professional societies invested in critical care echocardiography was convened, with the Executive Director representing the National Board of Echocardiography. Using an examination content outline, the writing committee was assigned topics relevant to their areas of expertise. The examination items underwent extensive review, editing, and discussion in several face-to-face meetings supervised by National Board of Medical Examiners editors and psychometricians. A separate certification committee was tasked with establishing criteria required to achieve National Board of Echocardiography certification in critical care echocardiography through detailed review of required supporting material submitted by candidates seeking to fulfill these criteria.

SETTING

The writing committee met twice a year in person at the National Board of Medical Examiner office in Philadelphia, PA.

SUBJECTS

Physicians enrolled in the examination of Special Competence in Critical Care Electrocardiography (CCEeXAM).

MEASUREMENTS AND MAIN RESULTS

A total of 524 physicians sat for the examination, and 426 (81.3%) achieved a passing score. Of the examinees, 41% were anesthesiology trained, 33.2% had pulmonary/critical care background, and the majority had graduated training within the 10 years (91.6%). Most candidates work full-time at an academic hospital (46.9%).

CONCLUSIONS

The CCEeXAM is designed to assess a knowledge base that is shared with echocardiologists in addition to that which is unique to critical care. The National Board of Echocardiography certification establishes that the physician has achieved the ability to independently perform and interpret critical care echocardiography at a standard recognized by critical care professional societies encompassing a wide spectrum of backgrounds. The interest shown and the success achieved on the CCEeXAM by practitioners of critical care echocardiography support the standards set by the National Board of Echocardiography for testamur status and certification in this imaging specialty area.

Integrating Focused Cardiac Ultrasound Into Pediatric Septic Shock Assessment

OBJECTIVES

To assess focused cardiac ultrasound impact on clinician hemodynamic characterization of patients with suspected septic shock as well as expert-generated focused cardiac ultrasound algorithm performance.

DESIGN

Retrospective, observational study.

SETTING

Single-center, noncardiac PICU.

PATIENTS

Less than 18 years old receiving focused cardiac ultrasound study within 72 hours of sepsis pathway initiation from January 2014 to December 2016.

INTERVENTIONS

Hemodynamics of patients with suspected septic shock were characterized as fluid responsive, myocardial dysfunction, obstructive physiology, and/or reduced systemic vascular resistance by a bedside clinician before and immediately following focused cardiac ultrasound performance. The clinician's post-focused cardiac ultrasound hemodynamic assessments were compared with an expert-derived focused cardiac ultrasound algorithmic hemodynamic interpretation. Subsequent clinical management was assessed for alignment with focused cardiac ultrasound characterization and association with patient outcomes.

MEASUREMENTS AND MAIN RESULTS

Seventy-one patients with suspected septic shock (median, 4.7 yr; interquartile range, 1.6-8.1) received clinician performed focused cardiac ultrasound study within 72 hours of sepsis pathway initiation (median, 2.1 hr; interquartile range, -1.5 to 11.8 hr). Two patients did not have pre-focused cardiac ultrasound and 23 patients did not have post-focused cardiac ultrasound hemodynamic characterization by clinicians resulting in exclusion from related analyses. Post-focused cardiac ultrasound clinician hemodynamic characterization differed from pre-focused cardiac ultrasound characterization in 67% of patients (31/46). There was substantial concordance between clinician's post-focused cardiac ultrasound and algorithm hemodynamic characterization (33/48; κ = 0.66; CI, 0.51-0.80). Fluid responsive (κ = 0.62; CI, 0.40-0.84), obstructive physiology (к = 0.87; CI, 0.64-1.00), and myocardial dysfunction (1.00; CI, 1.00-1.00) demonstrated substantial to perfect concordance. Management within 4 hours of focused cardiac ultrasound aligned with algorithm characterization in 53 of 71 patients (75%). Patients with aligned management were less likely to have a complicated course (14/52, 27%) compared with misaligned management (8/19, 42%; p = 0.25).

CONCLUSIONS

Incorporation of focused cardiac ultrasound in the evaluation of patients with suspected septic shock frequently changed a clinician's characterization of hemodynamics. An expert-developed algorithm had substantial concordance with a clinician's post-focused cardiac ultrasound hemodynamic characterization. Management aligned with algorithm characterization may improve outcomes in children with suspected septic shock.

The Diagnosis of Acute Myocarditis in Emergency (DAME) score: improving diagnostics within the emergency department

PURPOSE

. The final diagnosis of myocarditis is challenging. The aim of our study was to provide the D.A.M.E. (Diagnosis of Acute Myocarditis in Emergency) Score for the fast identification of patients suffering from myocarditis at Emergency Department (ED).

METHODS

. This was a multicenter, retrospective study involving three centers. All medical records from January 2010 to December 2014 reporting a final discharge diagnosis of myocarditis were considered. One hundred-four patients (mean age: 40.2±16.5 years) were enrolled. Clinical, biochemical and instrumental data were gathered. Data were analysed by means of logistic regression model and factorial analysis. A validation cohort from a fourth center was enrolled.

RESULTS

. The final determinants of the DAME score were six: fever, chest pain, erythrocyte sedimentation rate (ESR) > 20 mm/h, C-reactive protein (hs-CRP) >3 mg/L, troponin serum levels >3 ng/L, and left ventricle ejection fraction < 50%. All of them received a specified score ranging from 0 to 4. A score > 4 was related to 75% probability of myocarditis; a final score ranging between 1 and 4 was related to 57% probability of myocarditis. ROC curve on the validation cohort (289 patients, 27 with myocarditis) demonstrated the best cut-off to be 7: AUC 0.958 (p< 0.001), sensibility: 100%, specificity: 85.11%, PPV: 40.9%, NPV: 100% (LR+: 6.72; LR-: 0.00). Logistic regression analysis revealed Odds Ratio equal to 2.83 (95% CI 1.90 - 4.20, p < 0.0001).

CONCLUSIONS

. DAME score can offer a reliable tool in ED setting for the evaluation of patients suffering from suspected myocarditis.

Retention of Point-of-Care Ultrasound Skills Among Practicing Physicians: Findings of the VA National POCUS Training Program

BACKGROUND

Point-of-care ultrasound (POCUS) use continues to increase in many specialties, but lack of POCUS training is a known barrier among practicing physicians. Many physicians are obtaining POCUS training through postgraduate courses, but the impact of these courses on skill retention and frequency of POCUS use post-course is unknown. The purpose of this study was to assess the change in POCUS knowledge, skills, and frequency of use after 6-9 months of participating in a brief training course.

METHODS

Course participants' POCUS knowledge and hands-on technical skills were tested pre-course using an online, 30-question knowledge test and a directly observed skills test, respectively. The same knowledge and skills tests were repeated immediately post-course and after 6-9 months using remote tele-ultrasound software. Course participants completed a survey on their POCUS use pre-course and after 6-9 months post-course.

RESULTS

There were 127 providers who completed the POCUS training course from October 2016 to November 2017. Knowledge test scores increased from a median of 60% to 90% immediately post-course followed by a slight decrease to 87% after 8 months post-course. Median skills test scores for 4 common POCUS applications (heart, lung, abdomen, vascular access) increased 36-74 points from pre-course to immediately post-course with a 2-7-point decrease after 8 months. Providers reported more frequent POCUS use post-course, which suggests application of their POCUS knowledge and skills in clinical practice. More frequent use of cardiac POCUS applications was associated with significantly greater retention of cardiac skills at 8 months.

CONCLUSIONS

Practicing physicians can retain POCUS knowledge and hands-on skills 8 months after participating in a 2.5-day POCUS training course, regardless of frequency of POCUS use post-course.

Focused Transesophageal Echocardiography During Cardiac Arrest Resuscitation: JACC Review Topic of the Week

Focused transthoracic echocardiography (TTE) during cardiac arrest resuscitation can enable the characterization of myocardial activity, identify potentially treatable pathologies, assist with rhythm interpretation, and provide prognostic information. However, an important limitation of TTE is the difficulty obtaining interpretable images due to external and patient-related limiting factors. Over the last decade, focused transesophageal echocardiography (TEE) has been proposed as a tool that is ideally suited to image patients in extremis-those in cardiac arrest and periarrest states. In addition to the same diagnostic and prognostic role provided by TTE images, TEE provides unique advantages including the potential to optimize the quality of chest compressions, shorten cardiopulmonary resuscitation interruptions, guide resuscitative procedures, and provides a continuous image of myocardial activity. This review discusses the rationale, supporting evidence, opportunities, and challenges, and proposes a research agenda for the use of focused TEE in cardiac arrest with the goal to improve resuscitation outcomes.

Evaluating the Right Ventricle in Acute and Chronic Pulmonary Embolism: Current and Future Considerations

The right ventricle (RV), due to its morphologic and physiologic differences, is susceptible to sudden increase in RV afterload, as noted in patients with acute pulmonary embolism (PE). Functional impairment of RV function is a stronger presage of adverse outcomes in acute PE than the location or burden of emboli. While current iterations of most clinical prognostic scores do not incorporate RV dysfunction, advancements in imaging have enabled more granular and accurate assessment of RV dysfunction in acute PE. RV enlargement and dysfunction on imaging is noted only in a subset of patients with acute PE and is dependent on underlying cardiopulmonary reserve and clot burden. Specific signs like McConnell's and "60/60" sign are noted in less than 20% of patients with acute PE. About 2% of patients with acute PE develop chronic thromboembolic pulmonary hypertension, characterized by continued deterioration in RV function in a subset of patients with a continuum of RV function from preserved to overt right heart failure. Advances in molecular and other imaging will help better characterize RV dysfunction in this population and evaluate the response to therapies.

Handheld Ultrasound Device Usage and Image Acquisition Ability Among Internal Medicine Trainees: A Randomized Trial

BACKGROUND

There is insufficient knowledge about how personal access to handheld ultrasound devices (HUDs) improves trainee learning with point-of-care ultrasound (POCUS).

OBJECTIVE

To assess whether HUDs, alongside a yearlong lecture series, improved trainee POCUS usage and ability to acquire images.

METHODS

Internal medicine intern physicians (n = 47) at a single institution from 2017 to 2018 were randomized 1:1 to receive personal HUDs (n = 24) for patient care/self-directed learning vs no-HUDs (n = 23). All interns received a repeated lecture series on cardiac, thoracic, and abdominal POCUS. Main outcome measures included self-reported HUD usage rates and post-intervention assessment scores using the Rapid Assessment of Competency in Echocardiography (RACE) scale between HUD and no-HUD groups.

RESULTS

HUD interns reported performing POCUS assessments on patients a mean 6.8 (SD 2.2) times per week vs 6.4 (SD 2.9) times per week in non-HUD arm (P = .66). There was no relationship between the number of self-reported examinations per week and a trainee's post-intervention RACE score (rho = 0.022, P = .95). HUD interns did not have significantly higher post-intervention RACE scores (median HUD score 17.0 vs no-HUD score 17.8; P = .72). Trainee confidence with cardiac POCUS did not correlate with RACE scores.

CONCLUSIONS

Personal HUDs without direct supervision did not increase the amount of POCUS usage or improve interns' acquisition abilities. Interns who reported performing more examinations per week did not have higher RACE scores. Improved HUD access and lectures without additional feedback may not improve POCUS mastery.

Point-of-Care Ultrasound (POCUS) for the Cardiothoracic Anesthesiologist

Point-of-Care Ultrasound (POCUS) is a valuable bedside diagnostic tool for a variety of expeditious clinical assessments or as guidance for a multitude of acute care procedures. Varying aspects of nearly all organ systems can be evaluated using POCUS and, with the increasing availability of affordable ultrasound systems over the past decade, many now refer to POCUS as the 21^st-century stethoscope. With the current available and growing evidence for the clinical value of POCUS, its utility across the perioperative arena adds enormous benefit to clinical decision-making. Cardiothoracic anesthesiologists routinely have used portable ultrasound systems for nearly as long as the technology has been available, making POCUS applications a natural extension of existing cardiothoracic anesthesia practice. This narrative review presents a broad discussion of the utility of POCUS for the cardiothoracic anesthesiologist in varying perioperative contexts, including the preoperative clinic, the operating room (OR), intensive care unit (ICU), and others. Furthermore, POCUS-related education, competence, and certification are addressed.

Good clinical practice for the use of vasopressor and inotropic drugs in critically ill patients: state-of-the-art and expert consensus

Vasopressors and inotropic agents are widely used in critical care. However, strong evidence supporting their use in critically ill patients is lacking in many clinical scenarios. Thus, the Italian Society of Anesthesia and Intensive Care (SIAARTI) promoted a project aimed to provide indications for good clinical practice on the use of vasopressors and inotropes, and on the management of critically ill patients with shock. A panel of 16 experts in the field of intensive care medicine and hemodynamics has been established. Systematic review of the available literature was performed based on PICO questions. Basing on available evidence, the panel prepared a summary of evidence and then wrote the clinical questions. A modified semi-quantitative RAND/UCLA appropriateness method has been used to determine the appropriateness of specific clinical scenarios. The panel identified 29 clinical questions for the use of vasopressors and inotropes in patients with septic shock and cardiogenic shock. High level of agreement exists among the panel members about appropriateness of inotropes/vasopressors' use in patients with septic shock and cardiogenic shock.

Diagnostic accuracy of inferior vena cava ultrasound for heart failure in patients with acute dyspnoea: a systematic review and meta-analysis

BACKGROUND

Dyspnoea is the most common sign of heart failure (HF). Patients accessing the ED for HF-related symptoms require fast diagnosis and early treatment. Transthoracic echocardiography has a crucial role in HF diagnosis, but requires qualified staff and adequate time for execution. The measurement of inferior vena cava (IVC) diameter has been recently proposed as a rapid, simple and reliable marker of volume overload. The aim of this systematic review was to assess the accuracy of IVC-ultrasound as a stand-alone test for HF diagnosis in patients presenting to the ED with acute dyspnoea.

METHODS

Studies evaluating the diagnostic accuracy of the inferior vena cava collapsibility index (IVC-CIx) for HF diagnosis were systematically searched in the EMBASE and MEDLINE databases (up to January 2018). Quality Assessment of Diagnostic Accuracy Studies 2 tool was used for the quality assessment of the primary studies. A bivariate random-effects regression approach was used for summary estimates of both sensitivity and specificity.

RESULTS

Seven studies, for a total of 591 patients, were included. Three studies were at low-risk of bias. All studies used a proper reference test. Weighted mean prevalence of HF was 49.3% at random-effect model (I² index for heterogeneity=74.7%). IVC-CIx bivariate weighted mean sensitivity was 79.1% (95% CI 68.5% to 86.8%) and bivariate weighted mean specificity was 81.8% (95% CI 75.0% to 87.0%).

CONCLUSIONS

Our findings suggest that the sensitivity and specificity of IVC-CIx are suboptimal to rule in or rule out HF diagnosis in patients with acute dyspnoea in the ED setting. Therefore, IVC-CIx is not advisable as a stand-alone test, but may be useful when integrated in a specific diagnostic algorithm for the differential diagnosis of acute dyspnoea.

Impact of Bedside Combined Cardiopulmonary Ultrasound on Etiological Diagnosis and Treatment of Acute Respiratory Failure in Critically Ill Patients

AIMS AND OBJECTIVES

To prospectively evaluate the impact of cardiopulmonary ultrasound (CPUS) on etiological diagnosis and treatment of critically ill acute respiratory failure (ARF) patients.

DESIGN

This is a prospective observational study conducted in a general intensive care unit (ICU) of a tertiary care center in India. Patients over 18 years old with presence of one of the objective criteria of ARF. Patients either consecutively admitted for ARF to ICU or already admitted to ICU for a different reason but later developed ARF during their hospital stay. Written informed consent in local language was obtained from next of kin.

INTERVENTIONS

All included patients underwent bedside CPUS including lung ultrasound (US) and transthoracic echocardiography plus targeted venous US by single investigator, blinded to clinical data. The US diagnosis of ARF etiology was shared with treating intensivist. Initial clinical diagnosis (ICD) and treatment plan (made before US) of each patient were compared with post-US clinical diagnosis and treatment plan. The changes in diagnosis and treatment up to 24 hours post-US were considered as impact of US.

RESULTS

Mean age of 108 included patients was 45.7 ± 20.4 years (standard deviation). The ICD was correct in 67.5% (73/108) cases, whereas the combined CPUS yielded correct etiological diagnosis in 88% (95/108) cases. Among the 108 included patients, etiological diagnosis of ARF was altered after CPUS in 40 (37%) patients, which included "diagnosis changed" in 18 (17%) and "diagnosis added" in 22 (20%). Treatment plan was changed in 39 (36%) patients after CPUS, which included surgical interventions in 17 (16%), changes in medical therapy in 12 (11%), and changes in ventilation strategy in 4 (3.5%) patients.

CONCLUSION

This study demonstrates that use of combined US approach as an initial test in ARF, improves diagnostic accuracy for identification of underlying etiology, and frequently changes clinical diagnosis and/or treatment.

HOW TO CITE THIS ARTICLE

Barman B, Parihar A, Kohli N, Agarwal A, Dwivedi DK, Kumari G. Impact of Bedside Combined Cardiopulmonary Ultrasound on Etiological Diagnosis and Treatment of Acute Respiratory Failure in Critically Ill Patients. Indian J Crit Care Med 2020;24(11):1062-1070.

Interplay between Nox2 Activity and Platelet Activation in Patients with Sepsis and Septic Shock: A Prospective Study

Background

Although preclinical studies highlighted the potential role of NADPH oxidase (NOX) in sepsis, only few studies evaluated the oxidative stress in patients with sepsis and septic shock. The objective of the study is to appraise the oxidative stress status and platelet function in patients with sepsis and septic shock compared to healthy controls.

Methods and Results

Patients with sepsis or septic shock admitted to the hospital Policlinico Umberto I (Sapienza University, Rome) underwent a blood sample collection within 1 hour from admission. Platelet aggregation, serum thromboxane B2 (TxB2), soluble NOX2-derived peptides (sNox2-dp), and hydrogen peroxide breakdown activity (HBA) were measured and compared to those of healthy volunteers. Overall, 33 patients were enrolled; of these, 20 (60.6%) had sepsis and 13 (39.4%) septic shock. Compared to healthy controls (n = 10, age 67.8 ± 3.2, male 50%), patients with sepsis and septic shock had higher platelet aggregation (49% (IQR 45-55), 60% (55.75-67.25), and 73% (IQR 69-80), respectively, p < 0.001), higher serum TxB2 (77.5 (56.5-86.25), 122.5 (114-131.5), and 210 (195-230) pmol/L, respectively, p < 0.001), higher sNox2-dp (10 (7.75-12), 19.5 (17.25-21), and 33 (29.5-39) pg/mL, respectively, p < 0.001), and lower HBA (75% (67.25-81.5), 50% (45-54.75), and 27% (21.5-32.5), respectively, p < 0.001). Although not statistically significant, a trend in higher levels of serum TxB2 and sNox2-dp in patients who died was observed.

Conclusions

Patients with septic shock exhibit higher Nox2 activity and platelet activation than patients with sepsis. These insights joined to better knowledge of these mechanisms could guide the identification of future prognostic biomarkers and new therapeutic strategies in the scenario of septic shock.

The Utility of Point-of-Care Transesophageal Echocardiography in the Intensive Care Unit for Detecting the Cause of Hemolytic Anemia After Ascending Aorta Replacement

Hemolysis is well-known as a complication after mitral valve surgery, and hemolytic anemia after valvular surgery in the intensive care unit (ICU) usually leads ICU physicians to a careful imaging examination. However, hemolytic anemia following aortic replacement rarely has been described and little is known. The authors present a patient with hemolytic anemia after ascending aortic replacement for type A aortic dissection repair. In the patient, transthoracic echocardiography (TTE), contrast-enhanced computed tomography (CT), and laboratory tests failed to identify the cause of hemolytic anemia. Transesophageal echocardiography (TEE) finally revealed a stenosis of the proximal anastomosis of the graft, with turbulent flow due to protrusion into the lumen. This finding was thought to represent the cause of hemolysis and was sufficient to convince the surgeons to repair the lesion. In the repair surgery, inversion of the inner felt strip that had been applied to the proximal anastomosis of the replacement ascending aorta was confirmed as shown with TEE, and the constricted anastomosis was repaired. Although TTE and CT generally have been used to identify the lesion of mechanical hemolysis after cardiac surgery, point-of-care TEE could have promptly identified the causative lesion in the present patient. Point-of-care TEE in the ICU could become a first-line imaging examination for postoperative hemolysis in cardiac patients.

Teaching vs learning: Impact of deliberate practice and formative feedback on developing point of care ultrasound skills

PURPOSE

The study investigators hypothesized that Point of Care Ultrasound (POCUS) training through bolus didactic and workshop experiences may be sufficient for trainees to learn the cognitive aspects, while an extended period of exposure with formative feedback is responsible for developing the psychomotor skills critical for POCUS.

METHODS

The investigators studied trainees over the course of an academic year. They compared trainees' performance on written (cognitive) and observed image acquisition (psychomotor) exams at baseline and at each subsequent quarter, using a stepped-wedge design. They performed linear regression analysis to determine which variables contributed to knowledge and psychomotor skill development.

RESULTS

Twenty-six trainees met the study requirements and participated in the POCUS curriculum. Participating in a POCUS rotation was consistently associated with an increase in psychomotor scores. There was no consistent variable to predict an increase in trainee's score on written knowledge assessments.

CONCLUSIONS

Extended exposure to POCUS over a 4-week rotation with direct and indirect formative feedback can explain difference in scores on psychomotor skills assessments. Trainees scored similarly on the written assessment with or without a POCUS rotation. Training through didactic and workshop experiences may be sufficient to learn the cognitive aspects, but not psychomotor skills required for POCUS.

Hemodynamics in Shock Patients Assessed by Critical Care Ultrasound and Its Relationship to Outcome: A Prospective Study

BACKGROUND

Shock is one of the causes of mortality in the intensive care unit (ICU). Traditionally, hemodynamics related to shock have been monitored by broad-spectrum devices with treatment guided by many inaccurate variables to describe the pathophysiological changes. Critical care ultrasound (CCUS) has been widely advocated as a preferred tool to monitor shock patients. The purpose of this study was to analyze and broaden current knowledge of the characteristics of ultrasonic hemodynamic pattern and investigate their relationship to outcome.

METHODS

This prospective study of shock patients in CCUS was conducted in 181 adult patients between April 2016 and June 2017 in the Department of Intensive Care Unit of West China Hospital. CCUS was performed within the initial 6 hours after shock patients were enrolled. The demographic and clinical characteristics, ultrasonic pattern of hemodynamics, and outcome were recorded. A stepwise bivariate logistic regression model was established to identify the correlation between ultrasonic variables and the 28-day mortality.

RESULTS

A total of 181 patients with shock were included in our study (male/female: 113/68). The mean age was 58.2 ± 18.0 years; the mean Acute Physiology and Chronic Health Evaluation II (APACHE II score) was 23.7 ± 8.7, and the 28-day mortality was 44.8% (81/181). The details of ultrasonic pattern were well represented, and the multivariate analysis revealed that mitral annular plane systolic excursion (MAPSE), mitral annular peak systolic velocity (S'-MV), tricuspid annular plane systolic excursion (TAPSE), and lung ultrasound score (LUSS) were the independent risk factors for 28-day mortality in our study, as well as APACHE II score, PaO2/FiO2, and lactate (p = 0.047, 0.041, 0.022, 0.002, 0.027, 0.028, and 0.01, respectively).

CONCLUSIONS

CCUS exam on admission provided valuable information to describe the pathophysiological changes of shock patients and the mechanism of shock. Several critical variables obtained by CCUS were related to outcome, hence deserving more attention in clinical decision-making. Trial Registration. The study was approved by the Ethics Committee of West China Hospital Review Board for human research with the following reference number 201736 and was registered on ClinicalTrials. This trial is registered with NCT03082326 on 3 March 2017 (retrospectively registered).

Transesophageal echocardiography (TEE) in cardiac arrest: results of a hands-on training for a simplified TEE protocol

Background

Integration of transesophageal echocardiography (TEE) with Focused Cardiac Ultrasound (FoCUS) can impact decision-making, assist in the diagnosis of reversible etiologies and help guiding resuscitation of patients with cardiac arrest.

Objective

To evaluate the ability of emergency physicians (EPs) to obtain and maintain skills in performing resusTEE after a course with clinical training in the cardiac surgery theatre.

Methods

Ten EPs without previous TEE experience underwent a resusTEE course, based on a 2-h workshop and an 8-h hands-on training. The training was performed in a cardiac surgery theatre tutored by cardiovascular anesthesiologists. The six taught views were mid-esophageal four-chamber (ME4CH), mid-esophageal long axis (MELAX), mid-esophageal two-chamber (ME2CH), mid-esophageal bicaval view (MEbicaval), transgastric short axis (TGSAX) and aorta view (AOview). The EPs were evaluated by a cardiovascular anesthesiologist at the end of the course as well as after 12 weeks according to a standardized evaluation method. Once the course was completed, resusTEE exams, performed by EPs in Emergency Department (ED), were monitored for a 12-week period.

Results

The average assessment of the ten EPs by the tutors was higher than 4 points out of 5, both at the end of the course and after 12 weeks. Probe insertion, acquisition and interpretation of the different views scored on average more than 4 points out of 5 except for TGSAX that showed worsening after 12 weeks. Trainees performed twelve resusTEE exams in ED in patients with out-of-hospital cardiac arrest (OHCA) over 12 weeks after the course. EPs used only four out of six taught views in clinical practice, in the following order of frequency: ME4CH, AOview, MEbicaval and MELAX.

Conclusions

EPs, after a course with clinical training in the cardiac surgery theatre, can successfully acquire and maintain the skills needed to perform resusTEE. However, among the six views learned in the course, EPs used only four of them (ME4CH, MEbicaval, MELAX and AOview).

A Shifting Paradigm: The Role of Focused Cardiac Ultrasound in Bedside Patient Assessment

Transthoracic echocardiography is the standard of care in anatomic and functional cardiovascular assessment; however, focused cardiac ultrasound (FoCUS) performed with portable ultrasound equipment is increasingly being used as an adjunct to comprehensive history and physical examination. FoCUS assessments, unlike formal echocardiography, are intended to assist physicians in answering explicit clinical questions with a narrow differential diagnosis in real time. Over the past decade, a growing body of literature has repeatedly shown the value that FoCUS adds to clinical evaluation. Specifically, FoCUS improves point-of-care diagnostic accuracy, which in turn modifies treatment plans, decreases time to diagnosis, and reduces resource utilization. Although less robust, there is also evidence showing improvement in clinical outcomes. Based on this evidence, clinicians, training programs, and clinical societies have embraced FoCUS as a tool to complement bedside patient evaluation. Herein, we review the evidence for FoCUS in clinical practice, specifically evaluating the diagnostic accuracy, the impact on clinical decision-making, and the effect on clinical outcomes.

Point-of-care ultrasound in pediatric anesthesia: perioperative considerations

PURPOSE OF REVIEW

To review the perioperative applications of point-of-care ultrasound (POCUS).

RECENT FINDINGS

The role of point-of-care ultrasonography for perioperative care is expanding with respect to perioperative application. The imaging approach can complement the physical exam and provide additional information for decision-making in pediatric perioperative medicine. This review will focus on applications in the following organ systems: airway, cardiac, pulmonary and gastric. Specifically, POCUS of the airway has been used to optimize endotracheal tube depth, aid in tube size selection and predict difficulty with laryngoscopy and intubation. Lung POCUS has been used to assess for causes hypoxemia as well as to optimize ventilatory mechanics. Cardiac POCUS has been used for assessment of hemodynamics, valvular and ventricular function. Gastric ultrasound has emerged as an evaluative mechanism of gastric content in the setting of fasting as well as to confirm placement of gastric tubes. The applications of POCUS in the perioperative setting continue to evolve as a reliable diagnostic tool that can assist in timely diagnosis, improve procedural safety and has the potential to improve patient outcomes.

SUMMARY

The utility of perioperative POCUS has been well demonstrated, specifically for examination of the airway, stomach and cardiopulmonary system. It is advisable for the novice sonographer to perform POCUS within the guidelines set by the American Society of Echocardiography regarding basic POCUS. As with all diagnostic modalities, understanding the limitations of ultrasound and POCUS as well as continuous self-assessment is crucial.

Transesophageal echocardiography instead or in addition to transthoracic echocardiography in evaluating haemodynamic problems in intubated critically ill patients

Background

Transesophageal echocardiography (TEE) performed by intensivists is increasingly used in critically ill patients. However, TEE is usually not the preferred monitoring tool, especially when transthoracic echocardiography (TTE) appears to have addressed the clinical problems. As a result, it remains largely unknown whether TEE is a clinically valuable replacement or supplement for TTE as a primary tool in evaluating haemodynamic problems in critically ill surgical patients. The purpose of this study was to assess the diagnostic and therapeutic value of TEE instead or in addition to TTE in critically ill surgical patients with hemodynamic instability.

Methods

A prospective observational study was conducted. A total of 68 consecutive patients were enrolled from December 2016 to February 2018. TEE was routinely performed in addition to TTE, and the imaging data from TTE and TEE were successively disclosed to two different primary physicians, who reported any resulting changes in management. The two physicians were required to reach a consensus if there was any disagreement. The results of the additional TEE examination were compared with the clinical findings and TTE information. The image quality of TTE views was classified as a good (score 2), suboptimal (score 1) or poor view (score 0). According to the scores of TTE images, the patients were divided into two groups: patients with adequate TTE views (score ≥6) and inadequate TTE views (score <6).

Results

The results of additional TEE examination were classified into four categories. TEE failed to provide additional information about the initial diagnosis and therapy (class 1) in 26 patients (38.2%). Of the remaining 42 patients (61.8%), TEE instead or in addition to TTE revealed new findings or led to significant changes in therapy, as TTE supplied inadequate information. TEE used in addition to TTE led to a new diagnosis without therapeutic implications (class 2) in 11 patients (16.2%) and made a major clinical contribution leading to a therapeutic change (class 3) in 23 patients (33.8%). TEE used instead of TTE determined the diagnosis and therapy in 8 patients (11.8%) whose haemodynamic problems could not be addressed by TTE (class 4). In total, TEE had critical therapeutic benefits (class 3 and 4) that was not provided by TTE in 31 patients (45.6%). Of particular concern was that TEE had a higher proportion of therapeutic benefits to patients with inadequate TTE views than those with adequate TTE views (54.3% vs. 27.3%, P=0.036).

Conclusions

TEE as a feasible clinical tool is useful for critically ill surgical patients with hemodynamic instability, especially for the patients with inadequate TTE views. TEE instead or in addition to TTE could provide valuable information for diagnosis, which may bring significant therapeutic benefits.

Hemodynamic monitoring using trans esophageal echocardiography in patients with shock

Circulatory shock is a life-threatening condition responsible for inadequate tissue perfusion. The objectives of hemodynamic monitoring in this setting are multiple: identifying the mechanisms of shock (hypovolemic, distributive, cardiogenic, obstructive); choosing the adequate therapeutic intervention, and evaluating the patient's response. Echocardiography is proposed as a first line tool for this assessment in the intensive care unit. As compared to trans-thoracic echocardiography (TTE), trans-esophageal echocardiography (TEE) offers a better echogenicity and is the best way to evaluate deep anatomic structures. The therapeutic implication of TEE leads to frequent changes in clinical management. It also allows depicting sources of inaccuracy of thermodilution-based hemodynamic monitoring. It is a semi invasive tool with a low rate of complications. The first step in the hemodynamic evaluation of shock is to characterize the mechanisms of circulatory failure among hypovolemia, vasoplegia, cardiac dysfunction, and obstruction. Echocardiographic evaluation includes evaluation of LV systolic and diastolic function, as well as RV function, pericardium, measure of stroke volume and cardiac output, and evaluation of hypovolemia and fluid responsiveness. TEE can be used as a semi-continuous monitoring tool and can be repeated before and after therapeutic interventions (vasopressors, inotropes, fluid therapy, specific treatment such as pericardial effusion evacuation) to evaluate efficacy and tolerance of therapeutic interventions. In conclusion, TEE plays an important role in the management of circulatory failure when TTE is not enough to answer to the questions, although it is not a continuous tool of monitoring. TEE results must be integrated in a global evaluation, the first step being clinical examination. Whether TEE-directed therapy and close hemodynamic monitoring of shock has an impact on outcome remains debated.

Influence of head-of-bed elevation on the measurement of inferior vena cava diameter and collapsibility

PURPOSE

Inferior vena cava (IVC) diameter and variation are commonly measured in the supine position to estimate intravascular volume status of critically ill patients. Many scientific societies describe the measurement of IVC diameter in the supine position. However, critically ill patients are rarely placed supine due to concerns for aspiration risk, worsened respiratory mechanics, increases in intracranial pressure, and the time it takes to change patient position. We assessed the influence of head-of-bed (HOB) elevation on IVC measurements.

METHODS

We conducted a prospective observational study of critically ill patients undergoing critical care ultrasound. With HOB at 0°, IVC maximum (IVCmax0°) and minimum (IVCmin0°) diameters were measured. Measurements were then repeated with HOB elevated to 30° and 45°. Collapsibility index (CI), defined as (IVCmax - IVCmin)/IVCmax, was calculated for each HOB elevation. Mean differences were then compared.

RESULTS

A convenience sample of 95 patients was studied, of whom 45% were on vasopressors and 44% were spontaneously breathing. The CI did not significantly differ between the three positions. We found a significant difference (P ≤ .0001) between IVCmax at 45° (2.09 cm) and 0° (1.96 cm), IVCmin at 45° (1.75 cm) and 0° (1.59 cm), IVCmax at 45° (2.09 cm) and 30° (1.97 cm), and IVCmin at 45° (1.75 cm) and 30° (1.61 cm).

CONCLUSIONS

In a population of critically ill patients undergoing goal-directed ultrasound examinations, elevating HOB to 30° did not significantly alter IVC measurements or CI. At 45°, however, IVCmax and IVCmin diameters increased significantly, albeit with no significant change in CI. Performing ultrasound measurements of the IVC with HOB elevated to 30° is unlikely to produce clinically meaningful changes.

Diagnostic Ultrasound Safety Review for Point-of-Care Ultrasound Practitioners

Potential ultrasound exposure safety issues are reviewed, with guidance for prudent use of point-of-care ultrasound (POCUS). Safety assurance begins with the training of POCUS practitioners in the generation and interpretation of diagnostically valid and clinically relevant images. Sonographers themselves should minimize patient exposure in accordance with the as-low-as-reasonably-achievable principle, particularly for the safety of the eye, lung, and fetus. This practice entails the reduction of output indices or the exposure duration, consistent with the acquisition of diagnostically definitive images. Informed adoption of POCUS worldwide promises a reduction of ionizing radiation risks, enhanced cost-effectiveness, and prompt diagnoses for optimal patient care.

Prevention of pathogen transmission during ultrasound use in the Intensive Care Unit: Recommendations from the College of Intensive Care Medicine Ultrasound Special Interest Group (USIG)

ICU ultrasonography constitutes important part of modern car patient care. Current standards and practice of infection control and prevention are inadequate. This purpose of this document is to adapt and expand the 2017 Australasian Society for Ultrasound in Medicine (ASUM) and the Australasian College for Infection Prevention Control (ACIPC) guidelines on minimum standards for reprocessing/cleaning of ultrasound transducers to the specifics of intensive care medicine and provide advice to the ICU practitioners and health care administrators. It considers the medical, administrative, financial and practical controversies surrounding implementation, and addresses emerging issues of care for patients with confirmed or suspected Corona Virus Disease 2019 (COVID-19).

[Sonography in intensive care and emergency medicine : A new training concept]

Structured sonography training in internal medicine intensive care and emergency medicine (SIN) comprises two levels and was proposed by three national societies in Germany (DGIIN, DGK and DEGUM). The curriculum consists of a basic level (SIN-I) and an expert level (SIN-II) which are consecutive levels teaching both theoretical and hands-on skills using a symptom-based approach. Competency is assessed using written, oral and practical structured assessments at the end of each level. The goal is to implement national and international recommendations regarding the use of point-of-care ultrasound into clinical practice.