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.

Clinical Signs to Categorize Shock and Target Vasoactive Medications in Warm Versus Cold Pediatric Septic Shock.

OBJECTIVES: Determine level of agreement among clinical signs of shock type, identify which signs clinicians prioritize to determine shock type and select vasoactive medications, and test the association of shock type-vasoactive mismatch with prolonged organ dysfunction or death (complicated course). DESIGN: Retrospective observational study. SETTING: Single large academic PICU. PATIENTS: Patients less than 18 years treated on a critical care sepsis pathway between 2012 and 2016. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Agreement among clinical signs (extremity temperature, capillary refill, pulse strength, pulse pressure, and diastolic blood pressure) was measured using Fleiss and Cohen's κ. Association of clinical signs with shock type and shock type-vasoactive mismatch (e.g., cold shock treated with vasopressor rather than inotrope) with complicated course was determined using multivariable logistic regression. Of 469 patients, clinicians determined 307 (65%) had warm and 162 (35%) had cold shock. Agreement across all clinical signs was low (κ, 0.25; 95% CI, 0.20-0.30), although agreement between extremity temperature, capillary refill, and pulse strength was better than with pulse pressure and diastolic blood pressure. Only extremity temperature (adjusted odds ratio, 26.6; 95% CI, 15.5-45.8), capillary refill (adjusted odds ratio, 15.7; 95% CI, 7.9-31.3), and pulse strength (adjusted odds ratio, 21.3; 95% CI, 8.6-52.7) were associated with clinician-documented shock type. Of the 86 patients initiated on vasoactive medications during the pathway, shock type was discordant from vasoactive medication (κ, 0.14; 95% CI, -0.03 to 0.31) and shock type-vasoactive mismatch was not associated with complicated course (adjusted odds ratio, 0.3; 95% CI, 0.1-1.02). CONCLUSIONS: Agreement was low among common clinical signs used to characterize shock type, with clinicians prioritizing extremity temperature, capillary refill, and pulse strength. Although clinician-assigned shock type was often discordant with vasoactive choice, shock type-vasoactive mismatch was not associated with complicated course. Categorizing shock based on clinical signs should be done cautiously.

Diaphragm Atrophy During Pediatric Acute Respiratory Failure Is Associated With Prolonged Noninvasive Ventilation Requirement Following Extubation.

OBJECTIVES: Diaphragm atrophy is evident during invasive ventilation for pediatric acute respiratory failure, but with unknown significance. We hypothesized that diaphragm atrophy in pediatric acute respiratory failure is associated with prolonged noninvasive positive pressure ventilation following extubation. DESIGN: Prospective observational study. SETTING: Single-center academic PICU. PATIENTS: Invasively ventilated children with acute respiratory failure. INTERVENTIONS: Diaphragm ultrasound was performed within 36 hours after intubation and repeated within 48 hours preceding extubation. Rapid shallow breathing index at 15 and 30 minutes of a spontaneous breathing trial and negative inspiratory force were collected in a subset of patients concurrently with the ultrasound measurements. MEASUREMENTS AND MAIN RESULTS: Diaphragm thickness at end-expiration was measured to assess for diaphragm atrophy during mechanical ventilation. Percentage change in diaphragm thickness at end-expiration was defined as baseline diaphragm thickness at end-expiration minus final, preextubation diaphragm thickness at end-expiration divided by baseline diaphragm thickness at end-expiration. The primary outcome measure was duration of noninvasive positive pressure ventilation following extubation with prolonged use defined as noninvasive positive pressure ventilation use for greater than 24 hours postextubation. Among 56 children, 47 (median age, 15.5 mo; interquartile range, 6-53 mo) had diaphragm thickness at end-expiration measured within 48 hours prior to extubation. Fourteen (30%) had prolonged noninvasive positive pressure ventilation use with median duration 110 hours (interquartile range, 52-130 hr). The median percentage change of diaphragm thickness at end-expiration from baseline among those with and without prolonged noninvasive positive pressure ventilation use was -20% (interquartile range, -32% to -10%) versus -7% (interquartile range, -21% to 0%) (p = 0.04). CONCLUSIONS: Diaphragm atrophy is associated with prolonged postextubation noninvasive positive pressure ventilation in children with acute respiratory failure. Serial bedside diaphragm ultrasound may identify children at risk for prolonged noninvasive positive pressure ventilation use after extubation.

Development and Implementation of a Bedside Peripherally Inserted Central Catheter Service in a PICU.

OBJECTIVES: To create a bedside peripherally inserted central catheter service to increase placement of bedside peripherally inserted central catheter in PICU patients. DESIGN: Two-phase observational, pre-post design. SETTING: Single-center quaternary noncardiac PICU. PATIENTS: All patients admitted to the PICU. INTERVENTIONS: From June 1, 2015, to May 31, 2017, a bedside peripherally inserted central catheter service team was created (phase I) and expanded (phase II) as part of a quality improvement initiative. A multidisciplinary team developed a PICU peripherally inserted central catheter evaluation tool to identify amenable patients and to suggest location and provider for procedure performance. Outcome, process, and balancing metrics were evaluated. MEASUREMENTS AND MAIN RESULTS: Bedside peripherally inserted central catheter service placed 130 of 493 peripherally inserted central catheter (26%) resulting in 2,447 hospital central catheter days. A shift in bedside peripherally inserted central catheter centerline proportion occurred during both phases. Median time from order to catheter placement was reduced for peripherally inserted central catheters placed by bedside peripherally inserted central catheter service compared with placement in interventional radiology (6 hr [interquartile range, 2-23 hr] vs 34 hr [interquartile range, 19-61 hr]; p < 0.001). Successful access was achieved by bedside peripherally inserted central catheter service providers in 96% of patients with central tip position in 97%. Bedside peripherally inserted central catheter service central line-associated bloodstream infection and venous thromboembolism rates were similar to rates for peripherally inserted central catheters placed in interventional radiology (all central line-associated bloodstream infection, 1.23 vs 2.18; p = 0.37 and venous thromboembolism, 1.63 vs 1.57; p = 0.91). Peripherally inserted central catheters in PICU patients had reduced in-hospital venous thromboembolism rate compared with PICU temporary catheter in PICU rate (1.59 vs 5.36; p < 0.001). CONCLUSIONS: Bedside peripherally inserted central catheter service implementation increased bedside peripherally inserted central catheter placement and employed a patient-centered and timely process. Balancing metrics including central line-associated bloodstream infection and venous thromboembolism rates were not significantly different between peripherally inserted central catheters placed by bedside peripherally inserted central catheter service and those placed in interventional radiology.

Diagnostic Bedside Ultrasound Program Development in Pediatric Critical Care Medicine: Results of a National Survey.

OBJECTIVES: To assess current diagnostic bedside ultrasound program core element (training, credentialing, image storage, documentation, and quality assurance) implementation across pediatric critical care medicine divisions in the United States. DESIGN: Cross-sectional questionnaire-based needs assessment survey. SETTING: Pediatric critical care medicine divisions with an Accreditation Council of Graduate Medical Education-accredited fellowship. RESPONDENTS: Divisional leaders in education and/or bedside ultrasound training. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Fifty-five of 67 pediatric critical care medicine divisions (82%) with an Accreditation Council of Graduate Medical Education-accredited fellowship provided responses. Overall, 63% of responding divisions (34/54) were clinically performing diagnostic bedside ultrasound studies with no difference between divisions with large versus small units. Diagnostic bedside ultrasound training is available for pediatric critical care medicine fellows within 67% of divisions (35/52) with no difference in availability between divisions with large versus small units. Other core elements were present in less than 25% of all divisions performing clinical studies, with a statistically significant increase in credentialing and documentation among divisions with large units (p = 0.048 and 0.01, respectively). All core elements were perceived to have not only high impact in program development but also high effort in implementation. Assuming that all structural elements could be effectively implemented within their division, 83% of respondents (43/52) agreed that diagnostic bedside ultrasound should be a core curricular component of fellowship education. CONCLUSIONS: Diagnostic bedside ultrasound is increasingly prevalent in training and clinical use across the pediatric critical care medicine landscape despite frequently absent core programmatic infrastructural elements. These core elements are perceived as important to program development, regardless of division unit size. Shared standardized resources may assist in reducing the effort in core element implementation and allow us to measure important educational and clinical outcomes.

Progressive Diaphragm Atrophy in Pediatric Acute Respiratory Failure.

OBJECTIVES: Diaphragm atrophy is associated with delayed weaning from mechanical ventilation and increased mortality in critically ill adults. We sought to test for the presence of diaphragm atrophy in children with acute respiratory failure. DESIGN: Prospective, observational study. SETTING: Single-center tertiary noncardiac PICU in a children's hospital. PATIENTS: Invasively ventilated children with acute respiratory failure. MEASUREMENTS AND MAIN RESULTS: Diaphragm thickness at end-expiration and end-inspiration were serially measured by ultrasound in 56 patients (median age, 17 mo; interquartile range, 5.5-52), first within 36 hours of intubation and last preceding extubation. The median duration of mechanical ventilation was 140 hours (interquartile range, 83-201). At initial measurement, thickness at end-expiration was 2.0 mm (interquartile range, 1.8-2.5) and thickness at end-inspiration was 2.5 mm (interquartile range, 2-2.8). The change in thickness at end-expiration during mechanical ventilation between first and last measurement was -13.8% (interquartile range, -27.4% to 0%), with a -3.4% daily atrophy rate (interquartile range, -5.6 to 0%). Thickening fraction = ([thickness at end-inspiration - thickness at end-expiration]/thickness at end-inspiration) throughout the course of mechanical ventilation was linearly correlated with spontaneous breathing fraction (beta coefficient, 9.4; 95% CI, 4.2-14.7; p = 0.001). For children with a period of spontaneous breathing fraction less than 0.5 during mechanical ventilation, those with exposure to a continuous neuromuscular blockade infusion (n = 15) had a significantly larger decrease in thickness at end-expiration compared with children with low spontaneous breathing fraction who were not exposed to a neuromuscular blockade infusion (n = 18) (-16.4%, [interquartile range, -28.4% to -7.0%] vs -7.3%; [interquartile range, -10.9% to -0%]; p = 0.036). CONCLUSIONS: Diaphragm atrophy is present in children on mechanical ventilation for acute respiratory failure. Diaphragm contractility, measured as thickening fraction, is strongly correlated with spontaneous breathing fraction. The combination of exposure to neuromuscular blockade infusion with low overall spontaneous breathing fraction is associated with a greater degree of atrophy.

Ultrasound Guidance and Other Determinants of Successful Peripheral Artery Catheterization in Critically Ill Children.

OBJECTIVE: Peripheral arterial catheterization is a common invasive procedure performed in critically ill children. However, the benefits of using ultrasound guidance for this procedure in critically ill children, especially when used by inexperienced trainees, are unclear. Our aims were to evaluate whether the use of ultrasound guidance for the placement of radial arterial catheters reduced time and improved success when compared with the palpation method and also to determine patient and trainee variables that influence procedure outcomes. Finally, we evaluated whether adoption of ultrasound guidance among trainees comes at the expense of learning landmark-based methods. DESIGN: Prospective observational cohort. SETTING: University affiliated PICU. PATIENTS: A total of 208 procedures performed by 45 trainees in 192 unique patients (1 mo to 20 yr old) were observed. INTERVENTION: Implementation of ultrasound curriculum. MEASUREMENTS AND MAIN RESULTS: The main outcome measures were time and number of attempts required for the procedure. Compared with palpation method, ultrasound guidance was associated with reduced procedure time (8.1 ± 5.2 min compared with 16.5 ± 8.8 min; p < 0.001), reduced number of attempts (3.1 ± 2.6 attempts compared with 6.9 ± 4.2 attempts; p < 0.001), and improved first attempt success rate (28% compared with 11%; p = 0.001) even after adjusting for key confounders in multivariate random effects models. The factors most likely to interfere with peripheral arterial catheterization are patient age, patient systolic blood pressure, patient body mass index, degree of fluid overload, and trainee months in fellowship. The use of ultrasound guidance mitigates the influence of each of these factors. We found no evidence that the adoption of ultrasound guidance by trainees is associated with reduced proficiency in landmark-based methods. CONCLUSIONS: The use of ultrasound guidance by trainees for radial artery catheterization in critically ill children is associated with improved outcomes compared with the palpation method.

Hemodynamic Bedside Ultrasound Image Quality and Interpretation After Implementation of a Training Curriculum for Pediatric Critical Care Medicine Providers.

OBJECTIVE: Bedside ultrasound for hemodynamic evaluation in critically ill children is increasingly recognized as an important skill for pediatric critical care medicine providers. Our institution implemented a training curriculum leading to institutional credentialing for pediatric critical care providers in nonprocedural bedside ultrasound core applications. We hypothesized that hemodynamic studies performed or supervised by credentialed providers (credentialed providers group) have better image quality and greater accuracy in interpretation than studies performed by non-credentialed providers without supervision (non-credentialed providers group). DESIGN: Retrospective descriptive study. SETTING: Single-center tertiary non-cardiac 55-bed PICU in a children's hospital. PATIENTS: Patients from October 2013 to January 2015, with hemodynamic bedside ultrasound performed and interpreted by pediatric critical care providers exposed to bedside ultrasound training. INTERVENTIONS: A cardiologist blinded to performer scored hemodynamic bedside ultrasound image quality for five core cardiac views (excellent = 3, good = 2, fair = 1, unacceptable = 0; median = quality score) and interpretation within 5 hemodynamic domains (agreement = 3, minor disagreement = 2, major disagreement = 1; median = interpretation score), as well as a global assessment of interpretation. MEASUREMENTS AND MAIN RESULTS: Eighty-one studies (45 in the credentialed providers group and 36 in the non-credentialed providers group) were evaluated. There was no statistically significant difference in quality score between groups (median: 1.4 [interquartile range: 0.8-1.8] vs median: 1.2 [interquartile range: 0.75-1.6]; p = 0.14]. Studies in the credentialed providers group had higher interpretation score than those in the non-credentialed providers group (median: 3 [interquartile range: 2.5-3) vs median: 2.67 [interquartile range: 2.25-3]; p = 0.04). Major disagreement between critical care provider and cardiology review occurred in 25 of 283 hemodynamic domains assessed (8.8%), with no statistically significant difference between credentialed providers and non-credentialed providers groups (6.1% vs 11.9%; p = 0.12). CONCLUSION: Hemodynamic bedside ultrasound performed or supervised by credentialed pediatric critical care providers had more accurate interpretation than studies performed by unsupervised non-credentialed providers. A rigorous pediatric critical care medicine bedside ultrasound credentialing program can train intensivists to attain adequate images and interpret those images appropriately.

Association of left ventricular systolic function and vasopressor support with survival following pediatric out-of-hospital cardiac arrest.

OBJECTIVES: To characterize the association of hospital discharge survival with left ventricular systolic function evaluated by transthoracic echocardiography and vasoactive infusion support following return of spontaneous circulation after pediatric out-of-hospital cardiac arrest. DESIGN: Retrospective case series. SETTING: Single-center tertiary care pediatric cardiac arrest and critical care referral center. PATIENTS: Consecutive out-of-hospital cardiac arrest patients less than 18 years surviving to PICU admission who had a transthoracic echocardiography obtained by the clinical team within 24 hours of admission from January 2006 to May 2012. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Fifty-eight patients had a post-return of spontaneous circulation transthoracic echocardiography performed within 24 hours of admission. The median time from return of spontaneous circulation to echo was 6.5 hours (interquartile range, 4.7, 15.0 hr). Left ventricular systolic function was decreased in 24 of 58 patients (41%). The mortality rate was 67% (39 of 58). Thirty-six patients (62%) received vasoactive infusions at the time of transthoracic echocardiography, and increased vasopressor inotropic score was associated with increased mortality on univariate analysis (p < 0.001). After controlling for defibrillation, vasopressor inotropic score, and interaction between vasopressor inotropic score and left ventricular systolic function, decreased left ventricular systolic function was associated with increased mortality (odds ratio, 13.7; 95% CI, 1.54-122). CONCLUSIONS: In patients receiving transthoracic echocardiography within the first 24 hours following return of spontaneous circulation after pediatric out-of-hospital cardiac arrest, decreased left ventricular systolic function and vasopressor use were common. Decreased left ventricular systolic function was associated with increased mortality.