Transthoracic Echocardiography in Pediatric Intensive Care: Impact on Medical and Surgical Management Shelby Kutty, MD1; Jonah E. Attebery, MD2; Emily M. Yeager, MD1; Swetha Natarajan, MD1; Ling Li, MD, PhD1; Qinghai Peng, MD, PhD1; Edward Truemper, MD, MSc2; James M. Hammel, MD3; David A. Danford, MD1
Objectives: Although transthoracic echocardiography is commonly performed in the PICU, its utility is not specifically known. The purpose of this investigation was to evaluate the clinical impact of echocardiography in the PICU in terms of frequency of unanticipated findings and the frequency and nature of clinical management changes attributed to the results of echocardiography. Design: Prospective cohort study. Setting: Nineteen-bed combined medical-surgical-cardiac PICU at a tertiary care children’s hospital. Patients: All patients in PICU undergoing transthoracic echocardiography. Interventions, Measurements, and Main Results: Data collected included echocardiography indications, pre-echocardiography clinical assessment of anticipated echocardiography findings, height, weight, primary diagnosis, age, and urgency (stat vs routine) of echocardiography. Input of the attending care team (intensivist, cardiologist, and/or cardiovascular surgeon) allowed classification of echocardiography results as either confirming the pre-echocardiography impression, altering the pre-echocardiography clinical impression regarding the indica tion for which the test was performed, or altering the impression by virtue of new findings unrelated to the specific indication. The nature of the new findings were recorded and categorized. The team recorded clinical management changes made in response
Division of Pediatric Cardiology, University of Nebraska Medical Center and Children’s Hospital and Medical Center, Omaha, NE. 2 Division of Critical Care, Children’s Hospital and Medical Center, Omaha, NE. 3 Division of Cardiothoracic Surgery, Children’s Hospital and Medical Center, Omaha, NE. Dr. Kutty receives support from the American College of Cardiology Foundation, the Children’s Hospital and Medical Center Foundation, and the American Heart Association. The remaining authors have disclosed that they do not have any potential conflicts of interest. For information regarding this article, E-mail: [email protected] Copyright © 2014 by the Society of Critical Care Medicine and the World Federation of Pediatric Intensive and Critical Care Societies DOI: 10.1097/PCC.0000000000000099 1
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to the echocardiography results; the nature of these were listed and categorized. Echocardiograms (n = 416) were performed in 132 patients. Of these, 244 echocardiograms (59%) were ordered on male patients, 31% were under 30 days old, median age was 103 days, 379 (91%) had a primary cardiac diagnosis, and 92 (22%) were ordered stat. Sixty-three percent of echocardiograms confirmed and 24% altered the pre-echocardiography impression regarding the indication for the echocardiography; 13% introduced new findings unrelated to the indication. Cardiac surgical revision was the management change required in 26 patients (6.3%). Stat echocardiography was more likely to alter the pre-echocardiography assessment than routine echocardiography (p < 0.001). Management changes were more commonly associated with stat echocardiograms (p = 0.002) and those with new unexpected findings (p < 0.001) but had no demonstrable association with age less than 30 days (p = 0.332). Conclusions: Unanticipated echocardiography results are common in the PICU, and they often alter the clinical impressions that prompted the echocardiogram or introduce new findings unrelated to the reason for which the echocardiogram was recorded. Clinical management changes attributable to echocardiography findings are frequent in the PICU, including occasional surgical intervention. Echocardiography adds diagnostic value and contributes to the management approach in the PICU, accounting for its frequent use. (Pediatr Crit Care Med 2014; 15:329–335) Key Words: clinical outcomes; diagnostic utility; echocardiography; pediatric; pediatric cardiology; pediatric intensive care
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espite temporal increases in the utilization of various forms of noninvasive cardiovascular imaging in recent years (1), evidence on the real benefits of imaging in terms of improved patient outcomes is limited (2). Echocardiography (ECHO), a frequently performed diagnostic test in ICUs, is generally considered a useful tool for clinicians caring for critically ill patients. There is high utilization of ECHO in the PICU; however, its utility is not specifically known. The www.pccmjournal.org
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benefits of ECHO are established in many settings, including the sick neonate or child with suspected heart disease (3–5), children with cancer (6–9), and the adult ICU (10–14), but most of the literature quantitatively addressing diagnostic yield of ECHO is in adult patients. These reports indicate that new findings are demonstrated on between 8% and 47% of examinations, and interventions are made in response to 5%–36% of ECHOs performed (12, 15–18). Tam et al (15) noted that the likelihood of management change in adults with unexpected ECHO findings was higher (58%) than that among those with expected findings (32%). The management changes reported in that study included medication adjustments and initiation or cancellation of additional noninvasive or invasive investigations (15). The widespread use of ECHO in the PICU implies a commonly held belief in its value for patient care, yet the validity of this belief is as yet unconfirmed (19, 20). Because of the major differences in medical and surgical issues between adults and critically ill children, simple extrapolation of these results to the PICU setting is inadvisable. The purpose of this study was to evaluate the clinical impact of ECHO in the PICU in terms of frequency of unanticipated findings and the frequency and nature of clinical management changes attributed to the results of ECHO. We hypothesized that ECHO is helpful for a large proportion of patients in the PICU for whom it is ordered but that there is great diversity in its impact on patient management. We further hypothesized that there are predictable circumstances in which ECHO might be anticipated to be most helpful. Accordingly, we chose to meticulously document the diagnoses and other circumstances prompting ECHO in the PICU and evaluate the changes in the diagnosis and therapy, if any, resulting from ECHO. The purposes of this study were to 1) determine the frequency with which transthoracic ECHO in the PICU provides results that change patient management and 2) identify clinical circumstances in which ECHO may have greater or lesser utility.
MATERIALS AND METHODS This was a single-center prospective research study conducted in a 19-bed combined medical-surgical and cardiac PICU at a tertiary care children’s hospital. The institutional review board approved the study protocol. Any patient admitted to the PICU 1) undergoing clinically indicated transthoracic ECHO and 2) age less than 18 years was eligible for inclusion. Specific exclusion criterion consisted of patients undergoing transesophageal ECHO. Data on both routine and stat-ordered ECHOs were collected, and there was no limitation to the number of studies collected per patient. Stat ECHO was defined as a study ordered to be done “stat” in the electronic hospital ordering system and performed within an hour of a physician order. Data were collected during the time of the ordering and interpretation of ECHO in the PICU. A standardized pre- and post-study case report form (Appendix 1) was used and completed by the pediatric resident in the PICU who was primarily responsible for the patient, after consultation with the treatment team consisting of the attending pediatric intensivist, cardiologist, and/or 330
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cardiothoracic surgeon. Chart review was used to record the following: patient weight, height, date of birth, and age at the time the study. Patients were classified as cardiac or noncardiac based on primary diagnosis. The ECHO laboratory is accredited by the Intersocietal Accreditation Commission for Echocardiography Laboratories (ICAEL) and follows the ICAEL-recommended standards for pediatric ECHO. The laboratory also adheres to taskforce guidelines from the Pediatric Council of the American Society of Echocardiography. In accordance with these guidelines, the ECHO protocol consisted of complete cardiac examinations performed by seven registered diagnostic cardiac sonographers. Four board-certified pediatric cardiologists provided interpretations for all ECHOs. Pretest impressions in most situations were formulated during discussions in the multidisciplinary morning rounds in the PICU that always involved the attending intensivist, cardiac surgeon, and cardiologist. Each interpretation was available for review of the attending care team in the electronic medical record within 1–8 hours of completion of the test based on the urgency of ordering. With the input of the attending care team (intensivist, cardiologist, and/or cardiovascular surgeon), either the attending intensivist or the assigned PICU pediatric resident after discussion with the attending intensivist classified ECHO results as (1) confirming the pre-ECHO impression, (2) altering the pre-ECHO clinical impression regarding the indication for which the test was performed, or (3) altering the impression by virtue of new findings unrelated to the specific indication. Mixed outcomes, those in which (3) coexists with (2) or (1) were classified as (3). After reviewing the interpretation of the ECHO, it was recorded if the ECHO confirmed or altered the prestudy clinical impression or indication in the case report form. The nature of any new finding(s) on ECHO was also listed and categorized. If the patient underwent an intervention based on the results of the ECHO, it was recorded without judgment as to the importance of the intervention. Two investigators (J.E.A., E.M.Y.) collected the pre- and post-test surveys and compiled the data on a weekly basis. Statistical Analysis Continuous variables are expressed as mean ± sd. Total counts and percentages are reported for categorical variables. Four outcomes of interest were identified: 1) unexpected new ECHO findings, 2) ECHO findings resulting in management change, 3) ECHO findings resulting in surgical intervention, and 4) ECHO results which confirm expected findings. Associations of categorical variables (gender, cardiovascular/cardiothoracic surgical patient, neonatal age group, and ECHO ordered stat) with each outcome were evaluated using chi-square analysis of 2 × 2 tables. Association of specific type of unexpected new ECHO finding (e.g., ventricular function change and pericardial effusion) with the outcome “ECHO finding resulting in management change” was evaluated using chi-square analysis of 2 × 2 tables or Fisher exact test when n was insufficient for reliable chi-square approximation. Threshold for statistical significance was p value of less than 0.05. Statistical analysis was May 2014 • Volume 15 • Number 4
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Characteristics of Patients for Whom Echocardiograms Were Evaluated Table 1. Variable
Echocardiography
n (%)
416
Male
244 (59)
< 30 d of age
129 (31)
Age range (yr)
0–18
Performed in cardiac patients Ordered stat
primary diagnosis, and the remainder was done to evaluate the heart in critical illness related to primary disease of other organ systems. Almost one fifth of the studies ECHOs were ordered stat.
379 (91) 92 (22)
performed using commercially available software (Minitab version 16.1; Minitab, State College, PA).
RESULTS Subject Characteristics Four hundred sixteen ECHOs performed in 132 subjects met the inclusion criteria between August 2011 and May 2012 (Table 1). Analysis was by ECHO and not by subject. Almost one third of the ECHOs were in neonates. Over 90% were performed in patients with a cardiac condition as the
Diagnostic Efficacy Figure 1 illustrates the general distribution of ECHO findings among the following categories: (a) confirmed pretest impression versus (b) altered pretest impression regarding the indication for the ECHO versus (c) provided new findings unrelated to the stated indication. If both (b) and (c) were true, this was categorized as (c). Only 63% of ECHOs confirmed the pretest impression. There were 99 instances (24%) in which ECHO altered the pretest impression regarding the specific indication for examination, and 55 instances (13%) in which ECHO provided new findings unrelated to the original indication for ECHO. The most common of the new findings not related to indication was change in ventricular function (n = 18) and a newly appreciated anatomic lesion, valvular regurgitation, or stenosis (n = 16). Less commonly, a catheter-related complication, thrombus, pericardial effusion, change in estimated pulmonary artery pressure, or change in the patency of the ductus arteriosus were encountered in the course of doing ECHO for other reasons.
Figure 1. Diagnostic efficacy of echocardiography (ECHO) in the PICU: proportion of ECHOs that confirmed or altered pretest impression regarding specific indications or demonstrated new findings unrelated to the indication (A). New findings unrelated to ECHO indication (B). Nature of clinical management changes attributed to ECHO results (C).
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Indications for ECHO In the known cardiac patient, the major indications for ECHO were respiratory distress, evaluation of cardiac function, evaluation for pulmonary hypertension, and evaluation on extracorporeal membrane oxygenator (ECMO) support. The major indication in the noncardiac patient was suspected heart disease due to respiratory distress, low cardiac output signs, new murmur, or abnormal chest radiograph. Common indications for stat ECHOs were acute respiratory distress, cardiac function assessment, or patient on ECMO, while for the routine ECHOs, assessment of ventricular function was the most common indication. Preoperative cardiac patients without fully defined defect and cardiac patients in whom ECHOs were performed to better delineate anatomy together comprised 17 patients. There were 37 noncardiac PICU patients in whom ECHOs were performed. Of these, ECHO altered clinical impression in 10 patients, disclosed new findings in seven patients, and resulted in management changes in eight patients. The seven new findings disclosed by ECHO were detection of dilated cardiomyopathy (two patients), pericardial effusion (one patient), mitral and aortic valvular heart disease (one patient), hypertrophic cardiomyopathy (one patient), pulmonary stenosis (one patient), and patent ductus arteriosus (one patient). Special Circumstances and ECHO Yield These results are shown in Table 2. ECHOs in neonates demonstrated new findings related or unrelated to the indication at similar rates to ECHOs in older subjects. Neonatal ECHO results prompted about the same rate of management changes overall as in older subjects but a greater rate of surgical interventions. ECHOs ordered by the cardiovascular team were far more likely to confirm the pretest expected findings, but there Table 2.
was a tendency for these to translate into more management changes and surgical interventions; this was not statistically significant. ECHOs ordered stat were less likely to confirm the pretest impression and more likely to result in management changes and surgical interventions than those ordered routinely. The clinical indication for stat echo was acute clinical deterioration in all instances, and surgical intervention was based on combination of stat ECHO finding and the clinical picture. Clinical Management Changes in Response to ECHO Results When the ECHO findings altered the pretest impression, or disclosed new findings unrelated to indication, there were 138 clinical management changes made in response to 132 ECHOs. The most common change in management was adjustment of inotropic medications (n = 44). Surgical interventions accounted for 26 of the management changes (20%). The various surgical interventions performed in response to the ECHO results consisted of emergent repair of total anomalous pulmonary venous drainage, revision of prior cardiac surgical repair, thrombectomy of Blalock-Taussig shunt, atrial thrombectomy, pulmonary artery band revision, revision of pulmonary artery stent, and placement on ECMO support. Seven diagnostic or interventional cardiac catheterizations were arranged based on ECHO findings. Other management changes are quite diverse and are summarized in Figure 1. ECHOs that altered the pretest impression regarding the indications for examination and those demonstrating new findings unrelated to indication for testing were both highly associated with management changes (p < 0.001). There were no demonstrable associations of management change with neonatal age group, primary cardiac or noncardiac diagnosis, or gender.
Classification of Echocardiography Yield in Special Circumstances
Variable
Confirmed Expected Findings
Unexpected New Findings
Resulted in Management Changes
Ordered by CV team
252/379 (66.5%)
47/379 (12.4%)
130/379 (34.3%)
12/37 (32.4%)
8/37 (21.6%)
8/37 (21.6%)
0/37 (0%)
χ2 = 16.863
χ2 = 2.498
χ2 = 2.445
χ2 = 2.707
p < 0.001
p = 0.114
p = 0.118
p = 0.100
Age < 30 d
90/129 (69.8%)
16/129 (12.4%)
47/129 (36.4%)
13/129 (10.1%)
Age > 30 d
174/287(60.6%)
39/287(13.6%)
91/287 (31.7%)
13/287 (4.5%)
Not ordered by CV team
Routine ECHO
26/379 (6.9%)
χ = 3.207
χ = 0.109
χ = 0.897
χ2 = 4.675
p = 0.073
p = 0.741
p = 0.344
p = 0.031
2
Stat ECHO
Resulted in Surgical Intervention
2
2
43/92(46.7%)
5/92 (5.4%)
43/92 (46.7%)
221/324(68.2%)
11/324 (3.4%)
95/324(29.3%)
χ = 14.245
χ = 0.806
χ = 9.806
χ2 = 12.519
p < 0.001
p = 0.369
p = 0.002
p < 0.001
2
2
2
13/92 (14.1%) 13/324 (4.0%)
CV = cardiovascular, ECHO = echocardiography.
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Management Impact of New ECHO Findings Unrelated to the Test Indication ECHOs that revealed new findings unrelated to indication for testing were more likely than others to result in changes in clinical management. Among these, changes in ventricular function, identification of an intracardiac or systemic venous thrombus, central catheter-related complication, pericardial effusion, pulmonary hypertension, or a new anatomic problem, valve regurgitation, or stenosis were all associated with a greater likelihood of a management change (Table 3).
DISCUSSION Performed in a PICU serving both cardiac and noncardiac patients, this prospective study demonstrated that over one third of ECHOs provided information that differs from the pretest impression and almost one third resulted in clinical management change. These observations alone would be a ringing endorsement for aggressive utilization of ECHO to address specific cardiovascular questions in critically ill pediatric patients. It is important to emphasize, however, that a significant minority of ECHOs recorded in this setting revealed clinically relevant findings unrelated to the stated indication for the test. The strong association of these surprises on ECHO with management changes emphasizes their clinical relevance. This speaks to the importance of performing as complete an ECHO as possible in the PICU setting, even if the stated indications for examination are somewhat narrow, as it suggests that ECHO may answer questions yet unasked by caregivers in the PICU. One circumstance in which clinical questions in PICU may be incompletely formulated is when there is rapid nonspecific clinical deterioration, at which time ECHO is commonly ordered stat. It is therefore not surprising that these are the very patients in whom ECHO may disclose new findings unrelated to the pretest indications. Published findings about the clinical utility of chest radiography led to analogous conclusions about the special value of that test in PICU patients in extremis (21). According to that same study, chest radiography was more often valuable in very young PICU patients, but our investigation did not demonstrate an exceptional value for ECHO in neonates (21). Table 3.
Investigating the diagnostic and therapeutic yield of ECHO is highly relevant to pediatric intensive care and cardiology practice. Before-after questionnaires have been used in prior studies to investigate the utility of diagnostic tests (9, 15). However, only a few prospective clinical outcome trials in pediatrics assess the clinical value of cardiac imaging of any sort (21–23). The settings for these were PICU, and they used similar approach to that of this investigation, but none of them studied the value of ECHO. Our study has limitations. Valuable as it might have been to confirm directly that use of ECHO results in lower mortality and morbidity in PICU, the study design does not permit this evaluation. We recognize that the highest standard of proof for such a hypothesis would have been a randomized clinical trial; however, randomization to deny ECHO to some but not others in PICU could never satisfy the ethical standard of equipoise. We therefore implemented a prospective, but nonrandomized, design in which “ECHO-motivated-management-changes” served as a surrogate for “adverse-outcomes-avoided.” The conclusions must be tempered with the understanding that they are drawn using this limited and indirect approach. Although the study included more than 400 ECHOs, even larger numbers would be required for meaningful evaluation of the relationship between specific ECHO findings and specific types of management changes. Because of the narrow setting in which the data were gathered, caution should be exercised in generalizing the conclusions to other populations outside PICU. Cardiac surgical patients and other cardiac patients comprised 91% of the study cohort, so likely skewed the frequency of occurrence of management changes (especially surgical intervention). Even with the questionnaire method used prospectively for this study, variability in pretest assumptions may exist among the respondent depending on his/her understanding of the patient’s indication for ECHO. In the current era, medical practice is value oriented, so outcomes attributable to the use of ECHO are highly relevant. Outcomes, however, are only one component of value, the other being cost. To our knowledge, the costs associated with use of ECHO in the PICU have not yet been systematically evaluated. Ideally, in addition to measuring the direct financial
Characteristics of Echocardiographies Resulting in Management Changes n
Resulting in ≥ 1 Intervention, n (%)
p
New unexpected echocardiography finding
55
39 (70.1)
< 0.001
Change in ventricular function
18
14 (77.8)
< 0.001
New anatomic finding, obstruction, or valve regurgitation
16
9 (56.2)
0.044
Thrombus or catheter malfunction issue
11
9 (81.8)
< 0.001
Pulmonary hypertension
4
4 (100)
0.004
Pericardial effusion
4
2 (50)
NA
Change in ductus arteriosus status
2
1 (50)
NA
Variable
NA = not applicable. Boldface font denotes statistical significance.
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impact of ECHO, future investigational designs would account for ECHO leading to, or eliminating the need for, additional costly diagnostic procedures in critically ill patients (e.g., cardiac catheterization or MRI). The question of value in cardiac imaging is further confounded by the emerging interest in hand-held ECHO in ICUs not only for focused diagnostic purposes but also to supplement physical examination and as an indicator of preload (24). Focused point-of-care examinations performed by noncardiologists are typically devoted to answering very specific clinical questions posed in response to a particular differential diagnosis, using the minimum and most efficient ECHO views and techniques (25). Examples include assessment of left ventricular systolic function, markers of volume status, and pericardial effusion. This study was not designed to evaluate either the costs or the clinical impact of point-of-care ECHO in the PICU. It has been suggested that the optimal use of ECHO by noncardiologists would require a rigorous training program, consisting of training in image acquisition by skilled cardiac sonographers, extensive hands-on experience, and ongoing feedback from experienced echocardiographers to improve accuracy of interpretation (26). Despite data indicating that focused training of intensivists results in acquisition of technical and interpretive skills (20), equivalence of this with classic diagnostic ECHO through an accredited laboratory is far from established. Therefore, rather than extrapolation of the results of this study to hand-held or point-of-care ECHO, de novo investigation of this modality in the PICU, its costs, and associations with outcome would be required to establish its value. The frequency of unexpected ECHO findings and the clinical value of this manifest by changes in clinical management are straightforward concepts, which establish the value of ECHO in PICU. This approach, however, leaves unaddressed the potential value of the negative result. Confirmation of the pre-ECHO diagnosis provides assurances that the prevailing understanding of cardiovascular anatomy and physiology is correct and that current management may safely be continued. Because this, too, likely has substantial favorable impact on patient care, the clinical value of ECHO in PICU may be substantially underestimated by this analysis.
CONCLUSIONS Despite the inherent limitations of this sort of investigation, this study documents that unanticipated ECHO findings are common in PICU and they often modify the clinical impressions that prompted the ECHO. Acceptable indications for ECHO in PICU have not yet been established with certainty by this or any other study. However, the data reported here suggest that these indications ought to be quite broad, and the threshold for recording an ECHO in PICU should be quite low. Indications for ECHO ought to include any realistic suspicions for any of the common findings encountered in this large series, especially those with strong association with alterations in clinical management. These include changes in ventricular function, intracardiac or systemic venous thrombus, central catheter-related 334
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complication, pericardial effusion, pulmonary hypertension, new anatomic problem, valve regurgitation, or stenosis.
ACKNOWLEDGMENTS The authors appreciate the assistance of Mohan Mysore, MD, Jayesh C. Thakker, MD, Bridget Norton, MD, Andrew J. Macfadyen, MD, Robert N. Chaplin, MD, Kim F. Duncan, MD, Luke Noronha, MD, Kelly Kadlec, MD, and Carolyn Chamberlain, RN, BSN, MPH. The contributions of Jeremy Toffle, MD, Brandi Reeve-Iverson, MD, and Amanda Montabano, MD, MPH, are also acknowledged.
REFERENCES
1. Lucas FL, DeLorenzo MA, Siewers AE, et al: Temporal trends in the utilization of diagnostic testing and treatments for cardiovascular disease in the United States, 1993-2001. Circulation 2006; 113:374–379 2. Douglas PS, Taylor A, Bild D, et al: Outcomes research in cardiovascular imaging: Report of a workshop sponsored by the National Heart, Lung, and Blood Institute. JACC Cardiovasc Imaging 2009; 2:897–907 3. Tomar M, Shrivastava S: Role of echocardiography in pediatric intensive care unit. Indian Heart J 2011; 63:127–135 4. Gutgesell HP, Huhta JC, Latson LA, et al: Accuracy of t wo-dimensional echocardiography in the diagnosis of congenital heart disease. Am J Cardiol 1985; 55:514–518 5. Huhta JC, Latson LA, Gutgesell HP, et al: Echocardiography in the diagnosis and management of symptomatic aortic valve stenosis in infants. Circulation 1984; 70:438–444 6. Rice MJ, Seward JB, Hagler DJ, et al: Impact of 2-dimensional echocardiography on the management of distressed newborns in whom cardiac disease is suspected. Am J Cardiol 1983; 51:288–292 7. Kadivar M, Kiani A, Kocharian A, et al: Echocardiography and management of sick neonates in the intensive care unit. Congenit Heart Dis 2008; 3:325–329 8. Moss S, Kitchiner DJ, Yoxall CW, et al: Evaluation of echocardiography on the neonatal unit. Arch Dis Child Fetal Neonatal Ed 2003; 88:F287–F290 9. Watts RG, George M, Johnson WH Jr: Pretreatment and routine echocardiogram monitoring during chemotherapy for anthracycline-induced cardiotoxicity rarely identifies significant cardiac dysfunction or alters treatment decisions: A 5-year review at a single pediatric oncology center. Cancer 2012; 118:1919–1924 10. Colreavy FB, Donovan K, Lee KY, et al: Transesophageal echocardiography in critically ill patients. Crit Care Med 2002; 30:989–996 11. Stanko LK, Jacobsohn E, Tam JW, et al: Transthoracic echocardiography: Impact on diagnosis and management in tertiary care intensive care units. Anaesth Intensive Care 2005; 33:492–496 12. Vignon P, Mentec H, Terré S, et al: Diagnostic accuracy and therapeutic impact of transthoracic and transesophageal echocardiography in mechanically ventilated patients in the ICU. Chest 1994; 106:1829–1834 13. Jensen MB, Sloth E, Larsen KM, et al: Transthoracic echocardiography for cardiopulmonary monitoring in intensive care. Eur J Anaesthesiol 2004; 21:700–707 14. Orme RM, Oram MP, McKinstry CE: Impact of echocardiography on patient management in the intensive care unit: An audit of district general hospital practice. Br J Anaesth 2009; 102:340–344 15. Tam JW, Nichol J, MacDiarmid AL, et al: What is the real clinical utility of echocardiography? A prospective observational study. J Am Soc Echocardiogr 1999; 12:689–697 16. Krumholz HM, Douglas PS, Goldman L, et al: Clinical utility of transthoracic two-dimensional and Doppler echocardiography. J Am Coll Cardiol 1994; 24:125–131 17. Waggoner AD, Harris KM, Braverman AC, et al: The role of transthoracic echocardiography in the management of patients seen May 2014 • Volume 15 • Number 4
Cardiac Intensive Care in an outpatient cardiology clinic. J Am Soc Echocardiogr 1996; 9:761–768 18. Goldman L, Cohn PF, Mudge GH Jr, et al: Clinical utility and management impact of M-mode echocardiography. Am J Med 1983; 75:49–56 19. Forrest CB, Shipman SA, Dougherty D, et al: Outcomes research in pediatric settings: Recent trends and future directions. Pediatrics 2003; 111:171–178 20. Klugman D, Berger JT: Echocardiography as a hemodynamic monitor in critically ill children. Pediatr Crit Care Med 2011; 12: S50–S54 21. Quasney MW, Goodman DM, Billow M, et al: Routine chest radiographs in pediatric intensive care units. Pediatrics 2001; 107:241–248
22. Hauser GJ, Pollack MM, Sivit CJ, et al: Routine chest radiographs in pediatric intensive care: A prospective study. Pediatrics 1989; 83:465–470 23. Sivit CJ, Taylor GA, Hauser GJ, et al: Efficacy of chest radiography in pediatric intensive care. AJR Am J Roentgenol 1989; 152:575–577 24. Spenceley N, MacLaren G, Kissoon N, et al: Monitoring in pediatric cardiac critical care: A worldwide perspective. Pediatr Crit Care Med 2011; 12:S76–S80 25. Arntfield RT, Millington SJ: Point of care cardiac ultrasound applications in the emergency department and intensive care unit—A review. Curr Cardiol Rev 2012; 8:98–108 26. Melamed R, Sprenkle MD, Ulstad VK, et al: Assessment of left ventricular function by intensivists using hand-held echocardiography. Chest 2009; 135:1416–1420
APPENDIX 1. Case Report Form
C. Other Cardiac function (arrhythmia, chemotherapy, transplant, other) Pulmonary hypertension On extracorporeal membrane oxygenator Rule out thrombus Rule out endocarditis Volume status of the patient/ventricular filling
INDICATIONS A. Rule out heart disease Low output/poor perfusion/acidosis/shock Murmur Cyanosis Abnormal chest radiograph Respiratory distress Syndrome Other B. Known heart disease: Rule out bad hemodynamic change Low output/acidosis/shock Change in murmur Cyanosis Abnormal chest radiograph Respiratory distress Ductal patency (systemic blood flow/pulmonary blood flow) Other
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OUTCOMES A. Echo-confirmed suspected condition (Y/N) B. Negative for condition suspected C. Incidental new finding (Y/N) Required/did not require immediate attention (Y/N) D. Change in management (Y/N) Type of change
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Objectives: Although transthoracic echocardiography is commonly performed in the PICU, its utility is not specifically known. The purpose of this investigation was to evaluate the clinical impact of echocardiography in the PICU in terms of frequency of unanticipated findings and the frequency and nature of clinical management changes attributed to the results of echocardiography. Design: Prospective cohort study. Setting: Nineteen-bed combined medical-surgical-cardiac PICU at a tertiary care children’s hospital. Patients: All patients in PICU undergoing transthoracic echocardiography. Interventions, Measurements, and Main Results: Data collected included echocardiography indications, pre-echocardiography clinical assessment of anticipated echocardiography findings, height, weight, primary diagnosis, age, and urgency (stat vs routine) of echocardiography. Input of the attending care team (intensivist, cardiologist, and/or cardiovascular surgeon) allowed classification of echocardiography results as either confirming the pre-echocardiography impression, altering the pre-echocardiography clinical impression regarding the indica tion for which the test was performed, or altering the impression by virtue of new findings unrelated to the specific indication. The nature of the new findings were recorded and categorized. The team recorded clinical management changes made in response
Division of Pediatric Cardiology, University of Nebraska Medical Center and Children’s Hospital and Medical Center, Omaha, NE. 2 Division of Critical Care, Children’s Hospital and Medical Center, Omaha, NE. 3 Division of Cardiothoracic Surgery, Children’s Hospital and Medical Center, Omaha, NE. Dr. Kutty receives support from the American College of Cardiology Foundation, the Children’s Hospital and Medical Center Foundation, and the American Heart Association. The remaining authors have disclosed that they do not have any potential conflicts of interest. For information regarding this article, E-mail: [email protected] Copyright © 2014 by the Society of Critical Care Medicine and the World Federation of Pediatric Intensive and Critical Care Societies DOI: 10.1097/PCC.0000000000000099 1
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to the echocardiography results; the nature of these were listed and categorized. Echocardiograms (n = 416) were performed in 132 patients. Of these, 244 echocardiograms (59%) were ordered on male patients, 31% were under 30 days old, median age was 103 days, 379 (91%) had a primary cardiac diagnosis, and 92 (22%) were ordered stat. Sixty-three percent of echocardiograms confirmed and 24% altered the pre-echocardiography impression regarding the indication for the echocardiography; 13% introduced new findings unrelated to the indication. Cardiac surgical revision was the management change required in 26 patients (6.3%). Stat echocardiography was more likely to alter the pre-echocardiography assessment than routine echocardiography (p < 0.001). Management changes were more commonly associated with stat echocardiograms (p = 0.002) and those with new unexpected findings (p < 0.001) but had no demonstrable association with age less than 30 days (p = 0.332). Conclusions: Unanticipated echocardiography results are common in the PICU, and they often alter the clinical impressions that prompted the echocardiogram or introduce new findings unrelated to the reason for which the echocardiogram was recorded. Clinical management changes attributable to echocardiography findings are frequent in the PICU, including occasional surgical intervention. Echocardiography adds diagnostic value and contributes to the management approach in the PICU, accounting for its frequent use. (Pediatr Crit Care Med 2014; 15:329–335) Key Words: clinical outcomes; diagnostic utility; echocardiography; pediatric; pediatric cardiology; pediatric intensive care
D
espite temporal increases in the utilization of various forms of noninvasive cardiovascular imaging in recent years (1), evidence on the real benefits of imaging in terms of improved patient outcomes is limited (2). Echocardiography (ECHO), a frequently performed diagnostic test in ICUs, is generally considered a useful tool for clinicians caring for critically ill patients. There is high utilization of ECHO in the PICU; however, its utility is not specifically known. The www.pccmjournal.org
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benefits of ECHO are established in many settings, including the sick neonate or child with suspected heart disease (3–5), children with cancer (6–9), and the adult ICU (10–14), but most of the literature quantitatively addressing diagnostic yield of ECHO is in adult patients. These reports indicate that new findings are demonstrated on between 8% and 47% of examinations, and interventions are made in response to 5%–36% of ECHOs performed (12, 15–18). Tam et al (15) noted that the likelihood of management change in adults with unexpected ECHO findings was higher (58%) than that among those with expected findings (32%). The management changes reported in that study included medication adjustments and initiation or cancellation of additional noninvasive or invasive investigations (15). The widespread use of ECHO in the PICU implies a commonly held belief in its value for patient care, yet the validity of this belief is as yet unconfirmed (19, 20). Because of the major differences in medical and surgical issues between adults and critically ill children, simple extrapolation of these results to the PICU setting is inadvisable. The purpose of this study was to evaluate the clinical impact of ECHO in the PICU in terms of frequency of unanticipated findings and the frequency and nature of clinical management changes attributed to the results of ECHO. We hypothesized that ECHO is helpful for a large proportion of patients in the PICU for whom it is ordered but that there is great diversity in its impact on patient management. We further hypothesized that there are predictable circumstances in which ECHO might be anticipated to be most helpful. Accordingly, we chose to meticulously document the diagnoses and other circumstances prompting ECHO in the PICU and evaluate the changes in the diagnosis and therapy, if any, resulting from ECHO. The purposes of this study were to 1) determine the frequency with which transthoracic ECHO in the PICU provides results that change patient management and 2) identify clinical circumstances in which ECHO may have greater or lesser utility.
MATERIALS AND METHODS This was a single-center prospective research study conducted in a 19-bed combined medical-surgical and cardiac PICU at a tertiary care children’s hospital. The institutional review board approved the study protocol. Any patient admitted to the PICU 1) undergoing clinically indicated transthoracic ECHO and 2) age less than 18 years was eligible for inclusion. Specific exclusion criterion consisted of patients undergoing transesophageal ECHO. Data on both routine and stat-ordered ECHOs were collected, and there was no limitation to the number of studies collected per patient. Stat ECHO was defined as a study ordered to be done “stat” in the electronic hospital ordering system and performed within an hour of a physician order. Data were collected during the time of the ordering and interpretation of ECHO in the PICU. A standardized pre- and post-study case report form (Appendix 1) was used and completed by the pediatric resident in the PICU who was primarily responsible for the patient, after consultation with the treatment team consisting of the attending pediatric intensivist, cardiologist, and/or 330
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cardiothoracic surgeon. Chart review was used to record the following: patient weight, height, date of birth, and age at the time the study. Patients were classified as cardiac or noncardiac based on primary diagnosis. The ECHO laboratory is accredited by the Intersocietal Accreditation Commission for Echocardiography Laboratories (ICAEL) and follows the ICAEL-recommended standards for pediatric ECHO. The laboratory also adheres to taskforce guidelines from the Pediatric Council of the American Society of Echocardiography. In accordance with these guidelines, the ECHO protocol consisted of complete cardiac examinations performed by seven registered diagnostic cardiac sonographers. Four board-certified pediatric cardiologists provided interpretations for all ECHOs. Pretest impressions in most situations were formulated during discussions in the multidisciplinary morning rounds in the PICU that always involved the attending intensivist, cardiac surgeon, and cardiologist. Each interpretation was available for review of the attending care team in the electronic medical record within 1–8 hours of completion of the test based on the urgency of ordering. With the input of the attending care team (intensivist, cardiologist, and/or cardiovascular surgeon), either the attending intensivist or the assigned PICU pediatric resident after discussion with the attending intensivist classified ECHO results as (1) confirming the pre-ECHO impression, (2) altering the pre-ECHO clinical impression regarding the indication for which the test was performed, or (3) altering the impression by virtue of new findings unrelated to the specific indication. Mixed outcomes, those in which (3) coexists with (2) or (1) were classified as (3). After reviewing the interpretation of the ECHO, it was recorded if the ECHO confirmed or altered the prestudy clinical impression or indication in the case report form. The nature of any new finding(s) on ECHO was also listed and categorized. If the patient underwent an intervention based on the results of the ECHO, it was recorded without judgment as to the importance of the intervention. Two investigators (J.E.A., E.M.Y.) collected the pre- and post-test surveys and compiled the data on a weekly basis. Statistical Analysis Continuous variables are expressed as mean ± sd. Total counts and percentages are reported for categorical variables. Four outcomes of interest were identified: 1) unexpected new ECHO findings, 2) ECHO findings resulting in management change, 3) ECHO findings resulting in surgical intervention, and 4) ECHO results which confirm expected findings. Associations of categorical variables (gender, cardiovascular/cardiothoracic surgical patient, neonatal age group, and ECHO ordered stat) with each outcome were evaluated using chi-square analysis of 2 × 2 tables. Association of specific type of unexpected new ECHO finding (e.g., ventricular function change and pericardial effusion) with the outcome “ECHO finding resulting in management change” was evaluated using chi-square analysis of 2 × 2 tables or Fisher exact test when n was insufficient for reliable chi-square approximation. Threshold for statistical significance was p value of less than 0.05. Statistical analysis was May 2014 • Volume 15 • Number 4
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Characteristics of Patients for Whom Echocardiograms Were Evaluated Table 1. Variable
Echocardiography
n (%)
416
Male
244 (59)
< 30 d of age
129 (31)
Age range (yr)
0–18
Performed in cardiac patients Ordered stat
primary diagnosis, and the remainder was done to evaluate the heart in critical illness related to primary disease of other organ systems. Almost one fifth of the studies ECHOs were ordered stat.
379 (91) 92 (22)
performed using commercially available software (Minitab version 16.1; Minitab, State College, PA).
RESULTS Subject Characteristics Four hundred sixteen ECHOs performed in 132 subjects met the inclusion criteria between August 2011 and May 2012 (Table 1). Analysis was by ECHO and not by subject. Almost one third of the ECHOs were in neonates. Over 90% were performed in patients with a cardiac condition as the
Diagnostic Efficacy Figure 1 illustrates the general distribution of ECHO findings among the following categories: (a) confirmed pretest impression versus (b) altered pretest impression regarding the indication for the ECHO versus (c) provided new findings unrelated to the stated indication. If both (b) and (c) were true, this was categorized as (c). Only 63% of ECHOs confirmed the pretest impression. There were 99 instances (24%) in which ECHO altered the pretest impression regarding the specific indication for examination, and 55 instances (13%) in which ECHO provided new findings unrelated to the original indication for ECHO. The most common of the new findings not related to indication was change in ventricular function (n = 18) and a newly appreciated anatomic lesion, valvular regurgitation, or stenosis (n = 16). Less commonly, a catheter-related complication, thrombus, pericardial effusion, change in estimated pulmonary artery pressure, or change in the patency of the ductus arteriosus were encountered in the course of doing ECHO for other reasons.
Figure 1. Diagnostic efficacy of echocardiography (ECHO) in the PICU: proportion of ECHOs that confirmed or altered pretest impression regarding specific indications or demonstrated new findings unrelated to the indication (A). New findings unrelated to ECHO indication (B). Nature of clinical management changes attributed to ECHO results (C).
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Indications for ECHO In the known cardiac patient, the major indications for ECHO were respiratory distress, evaluation of cardiac function, evaluation for pulmonary hypertension, and evaluation on extracorporeal membrane oxygenator (ECMO) support. The major indication in the noncardiac patient was suspected heart disease due to respiratory distress, low cardiac output signs, new murmur, or abnormal chest radiograph. Common indications for stat ECHOs were acute respiratory distress, cardiac function assessment, or patient on ECMO, while for the routine ECHOs, assessment of ventricular function was the most common indication. Preoperative cardiac patients without fully defined defect and cardiac patients in whom ECHOs were performed to better delineate anatomy together comprised 17 patients. There were 37 noncardiac PICU patients in whom ECHOs were performed. Of these, ECHO altered clinical impression in 10 patients, disclosed new findings in seven patients, and resulted in management changes in eight patients. The seven new findings disclosed by ECHO were detection of dilated cardiomyopathy (two patients), pericardial effusion (one patient), mitral and aortic valvular heart disease (one patient), hypertrophic cardiomyopathy (one patient), pulmonary stenosis (one patient), and patent ductus arteriosus (one patient). Special Circumstances and ECHO Yield These results are shown in Table 2. ECHOs in neonates demonstrated new findings related or unrelated to the indication at similar rates to ECHOs in older subjects. Neonatal ECHO results prompted about the same rate of management changes overall as in older subjects but a greater rate of surgical interventions. ECHOs ordered by the cardiovascular team were far more likely to confirm the pretest expected findings, but there Table 2.
was a tendency for these to translate into more management changes and surgical interventions; this was not statistically significant. ECHOs ordered stat were less likely to confirm the pretest impression and more likely to result in management changes and surgical interventions than those ordered routinely. The clinical indication for stat echo was acute clinical deterioration in all instances, and surgical intervention was based on combination of stat ECHO finding and the clinical picture. Clinical Management Changes in Response to ECHO Results When the ECHO findings altered the pretest impression, or disclosed new findings unrelated to indication, there were 138 clinical management changes made in response to 132 ECHOs. The most common change in management was adjustment of inotropic medications (n = 44). Surgical interventions accounted for 26 of the management changes (20%). The various surgical interventions performed in response to the ECHO results consisted of emergent repair of total anomalous pulmonary venous drainage, revision of prior cardiac surgical repair, thrombectomy of Blalock-Taussig shunt, atrial thrombectomy, pulmonary artery band revision, revision of pulmonary artery stent, and placement on ECMO support. Seven diagnostic or interventional cardiac catheterizations were arranged based on ECHO findings. Other management changes are quite diverse and are summarized in Figure 1. ECHOs that altered the pretest impression regarding the indications for examination and those demonstrating new findings unrelated to indication for testing were both highly associated with management changes (p < 0.001). There were no demonstrable associations of management change with neonatal age group, primary cardiac or noncardiac diagnosis, or gender.
Classification of Echocardiography Yield in Special Circumstances
Variable
Confirmed Expected Findings
Unexpected New Findings
Resulted in Management Changes
Ordered by CV team
252/379 (66.5%)
47/379 (12.4%)
130/379 (34.3%)
12/37 (32.4%)
8/37 (21.6%)
8/37 (21.6%)
0/37 (0%)
χ2 = 16.863
χ2 = 2.498
χ2 = 2.445
χ2 = 2.707
p < 0.001
p = 0.114
p = 0.118
p = 0.100
Age < 30 d
90/129 (69.8%)
16/129 (12.4%)
47/129 (36.4%)
13/129 (10.1%)
Age > 30 d
174/287(60.6%)
39/287(13.6%)
91/287 (31.7%)
13/287 (4.5%)
Not ordered by CV team
Routine ECHO
26/379 (6.9%)
χ = 3.207
χ = 0.109
χ = 0.897
χ2 = 4.675
p = 0.073
p = 0.741
p = 0.344
p = 0.031
2
Stat ECHO
Resulted in Surgical Intervention
2
2
43/92(46.7%)
5/92 (5.4%)
43/92 (46.7%)
221/324(68.2%)
11/324 (3.4%)
95/324(29.3%)
χ = 14.245
χ = 0.806
χ = 9.806
χ2 = 12.519
p < 0.001
p = 0.369
p = 0.002
p < 0.001
2
2
2
13/92 (14.1%) 13/324 (4.0%)
CV = cardiovascular, ECHO = echocardiography.
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Management Impact of New ECHO Findings Unrelated to the Test Indication ECHOs that revealed new findings unrelated to indication for testing were more likely than others to result in changes in clinical management. Among these, changes in ventricular function, identification of an intracardiac or systemic venous thrombus, central catheter-related complication, pericardial effusion, pulmonary hypertension, or a new anatomic problem, valve regurgitation, or stenosis were all associated with a greater likelihood of a management change (Table 3).
DISCUSSION Performed in a PICU serving both cardiac and noncardiac patients, this prospective study demonstrated that over one third of ECHOs provided information that differs from the pretest impression and almost one third resulted in clinical management change. These observations alone would be a ringing endorsement for aggressive utilization of ECHO to address specific cardiovascular questions in critically ill pediatric patients. It is important to emphasize, however, that a significant minority of ECHOs recorded in this setting revealed clinically relevant findings unrelated to the stated indication for the test. The strong association of these surprises on ECHO with management changes emphasizes their clinical relevance. This speaks to the importance of performing as complete an ECHO as possible in the PICU setting, even if the stated indications for examination are somewhat narrow, as it suggests that ECHO may answer questions yet unasked by caregivers in the PICU. One circumstance in which clinical questions in PICU may be incompletely formulated is when there is rapid nonspecific clinical deterioration, at which time ECHO is commonly ordered stat. It is therefore not surprising that these are the very patients in whom ECHO may disclose new findings unrelated to the pretest indications. Published findings about the clinical utility of chest radiography led to analogous conclusions about the special value of that test in PICU patients in extremis (21). According to that same study, chest radiography was more often valuable in very young PICU patients, but our investigation did not demonstrate an exceptional value for ECHO in neonates (21). Table 3.
Investigating the diagnostic and therapeutic yield of ECHO is highly relevant to pediatric intensive care and cardiology practice. Before-after questionnaires have been used in prior studies to investigate the utility of diagnostic tests (9, 15). However, only a few prospective clinical outcome trials in pediatrics assess the clinical value of cardiac imaging of any sort (21–23). The settings for these were PICU, and they used similar approach to that of this investigation, but none of them studied the value of ECHO. Our study has limitations. Valuable as it might have been to confirm directly that use of ECHO results in lower mortality and morbidity in PICU, the study design does not permit this evaluation. We recognize that the highest standard of proof for such a hypothesis would have been a randomized clinical trial; however, randomization to deny ECHO to some but not others in PICU could never satisfy the ethical standard of equipoise. We therefore implemented a prospective, but nonrandomized, design in which “ECHO-motivated-management-changes” served as a surrogate for “adverse-outcomes-avoided.” The conclusions must be tempered with the understanding that they are drawn using this limited and indirect approach. Although the study included more than 400 ECHOs, even larger numbers would be required for meaningful evaluation of the relationship between specific ECHO findings and specific types of management changes. Because of the narrow setting in which the data were gathered, caution should be exercised in generalizing the conclusions to other populations outside PICU. Cardiac surgical patients and other cardiac patients comprised 91% of the study cohort, so likely skewed the frequency of occurrence of management changes (especially surgical intervention). Even with the questionnaire method used prospectively for this study, variability in pretest assumptions may exist among the respondent depending on his/her understanding of the patient’s indication for ECHO. In the current era, medical practice is value oriented, so outcomes attributable to the use of ECHO are highly relevant. Outcomes, however, are only one component of value, the other being cost. To our knowledge, the costs associated with use of ECHO in the PICU have not yet been systematically evaluated. Ideally, in addition to measuring the direct financial
Characteristics of Echocardiographies Resulting in Management Changes n
Resulting in ≥ 1 Intervention, n (%)
p
New unexpected echocardiography finding
55
39 (70.1)
< 0.001
Change in ventricular function
18
14 (77.8)
< 0.001
New anatomic finding, obstruction, or valve regurgitation
16
9 (56.2)
0.044
Thrombus or catheter malfunction issue
11
9 (81.8)
< 0.001
Pulmonary hypertension
4
4 (100)
0.004
Pericardial effusion
4
2 (50)
NA
Change in ductus arteriosus status
2
1 (50)
NA
Variable
NA = not applicable. Boldface font denotes statistical significance.
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impact of ECHO, future investigational designs would account for ECHO leading to, or eliminating the need for, additional costly diagnostic procedures in critically ill patients (e.g., cardiac catheterization or MRI). The question of value in cardiac imaging is further confounded by the emerging interest in hand-held ECHO in ICUs not only for focused diagnostic purposes but also to supplement physical examination and as an indicator of preload (24). Focused point-of-care examinations performed by noncardiologists are typically devoted to answering very specific clinical questions posed in response to a particular differential diagnosis, using the minimum and most efficient ECHO views and techniques (25). Examples include assessment of left ventricular systolic function, markers of volume status, and pericardial effusion. This study was not designed to evaluate either the costs or the clinical impact of point-of-care ECHO in the PICU. It has been suggested that the optimal use of ECHO by noncardiologists would require a rigorous training program, consisting of training in image acquisition by skilled cardiac sonographers, extensive hands-on experience, and ongoing feedback from experienced echocardiographers to improve accuracy of interpretation (26). Despite data indicating that focused training of intensivists results in acquisition of technical and interpretive skills (20), equivalence of this with classic diagnostic ECHO through an accredited laboratory is far from established. Therefore, rather than extrapolation of the results of this study to hand-held or point-of-care ECHO, de novo investigation of this modality in the PICU, its costs, and associations with outcome would be required to establish its value. The frequency of unexpected ECHO findings and the clinical value of this manifest by changes in clinical management are straightforward concepts, which establish the value of ECHO in PICU. This approach, however, leaves unaddressed the potential value of the negative result. Confirmation of the pre-ECHO diagnosis provides assurances that the prevailing understanding of cardiovascular anatomy and physiology is correct and that current management may safely be continued. Because this, too, likely has substantial favorable impact on patient care, the clinical value of ECHO in PICU may be substantially underestimated by this analysis.
CONCLUSIONS Despite the inherent limitations of this sort of investigation, this study documents that unanticipated ECHO findings are common in PICU and they often modify the clinical impressions that prompted the ECHO. Acceptable indications for ECHO in PICU have not yet been established with certainty by this or any other study. However, the data reported here suggest that these indications ought to be quite broad, and the threshold for recording an ECHO in PICU should be quite low. Indications for ECHO ought to include any realistic suspicions for any of the common findings encountered in this large series, especially those with strong association with alterations in clinical management. These include changes in ventricular function, intracardiac or systemic venous thrombus, central catheter-related 334
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complication, pericardial effusion, pulmonary hypertension, new anatomic problem, valve regurgitation, or stenosis.
ACKNOWLEDGMENTS The authors appreciate the assistance of Mohan Mysore, MD, Jayesh C. Thakker, MD, Bridget Norton, MD, Andrew J. Macfadyen, MD, Robert N. Chaplin, MD, Kim F. Duncan, MD, Luke Noronha, MD, Kelly Kadlec, MD, and Carolyn Chamberlain, RN, BSN, MPH. The contributions of Jeremy Toffle, MD, Brandi Reeve-Iverson, MD, and Amanda Montabano, MD, MPH, are also acknowledged.
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1. Lucas FL, DeLorenzo MA, Siewers AE, et al: Temporal trends in the utilization of diagnostic testing and treatments for cardiovascular disease in the United States, 1993-2001. Circulation 2006; 113:374–379 2. Douglas PS, Taylor A, Bild D, et al: Outcomes research in cardiovascular imaging: Report of a workshop sponsored by the National Heart, Lung, and Blood Institute. JACC Cardiovasc Imaging 2009; 2:897–907 3. Tomar M, Shrivastava S: Role of echocardiography in pediatric intensive care unit. Indian Heart J 2011; 63:127–135 4. Gutgesell HP, Huhta JC, Latson LA, et al: Accuracy of t wo-dimensional echocardiography in the diagnosis of congenital heart disease. Am J Cardiol 1985; 55:514–518 5. Huhta JC, Latson LA, Gutgesell HP, et al: Echocardiography in the diagnosis and management of symptomatic aortic valve stenosis in infants. Circulation 1984; 70:438–444 6. Rice MJ, Seward JB, Hagler DJ, et al: Impact of 2-dimensional echocardiography on the management of distressed newborns in whom cardiac disease is suspected. Am J Cardiol 1983; 51:288–292 7. Kadivar M, Kiani A, Kocharian A, et al: Echocardiography and management of sick neonates in the intensive care unit. Congenit Heart Dis 2008; 3:325–329 8. Moss S, Kitchiner DJ, Yoxall CW, et al: Evaluation of echocardiography on the neonatal unit. Arch Dis Child Fetal Neonatal Ed 2003; 88:F287–F290 9. Watts RG, George M, Johnson WH Jr: Pretreatment and routine echocardiogram monitoring during chemotherapy for anthracycline-induced cardiotoxicity rarely identifies significant cardiac dysfunction or alters treatment decisions: A 5-year review at a single pediatric oncology center. Cancer 2012; 118:1919–1924 10. Colreavy FB, Donovan K, Lee KY, et al: Transesophageal echocardiography in critically ill patients. Crit Care Med 2002; 30:989–996 11. Stanko LK, Jacobsohn E, Tam JW, et al: Transthoracic echocardiography: Impact on diagnosis and management in tertiary care intensive care units. Anaesth Intensive Care 2005; 33:492–496 12. Vignon P, Mentec H, Terré S, et al: Diagnostic accuracy and therapeutic impact of transthoracic and transesophageal echocardiography in mechanically ventilated patients in the ICU. Chest 1994; 106:1829–1834 13. Jensen MB, Sloth E, Larsen KM, et al: Transthoracic echocardiography for cardiopulmonary monitoring in intensive care. Eur J Anaesthesiol 2004; 21:700–707 14. Orme RM, Oram MP, McKinstry CE: Impact of echocardiography on patient management in the intensive care unit: An audit of district general hospital practice. Br J Anaesth 2009; 102:340–344 15. Tam JW, Nichol J, MacDiarmid AL, et al: What is the real clinical utility of echocardiography? A prospective observational study. J Am Soc Echocardiogr 1999; 12:689–697 16. Krumholz HM, Douglas PS, Goldman L, et al: Clinical utility of transthoracic two-dimensional and Doppler echocardiography. J Am Coll Cardiol 1994; 24:125–131 17. Waggoner AD, Harris KM, Braverman AC, et al: The role of transthoracic echocardiography in the management of patients seen May 2014 • Volume 15 • Number 4
Cardiac Intensive Care in an outpatient cardiology clinic. J Am Soc Echocardiogr 1996; 9:761–768 18. Goldman L, Cohn PF, Mudge GH Jr, et al: Clinical utility and management impact of M-mode echocardiography. Am J Med 1983; 75:49–56 19. Forrest CB, Shipman SA, Dougherty D, et al: Outcomes research in pediatric settings: Recent trends and future directions. Pediatrics 2003; 111:171–178 20. Klugman D, Berger JT: Echocardiography as a hemodynamic monitor in critically ill children. Pediatr Crit Care Med 2011; 12: S50–S54 21. Quasney MW, Goodman DM, Billow M, et al: Routine chest radiographs in pediatric intensive care units. Pediatrics 2001; 107:241–248
22. Hauser GJ, Pollack MM, Sivit CJ, et al: Routine chest radiographs in pediatric intensive care: A prospective study. Pediatrics 1989; 83:465–470 23. Sivit CJ, Taylor GA, Hauser GJ, et al: Efficacy of chest radiography in pediatric intensive care. AJR Am J Roentgenol 1989; 152:575–577 24. Spenceley N, MacLaren G, Kissoon N, et al: Monitoring in pediatric cardiac critical care: A worldwide perspective. Pediatr Crit Care Med 2011; 12:S76–S80 25. Arntfield RT, Millington SJ: Point of care cardiac ultrasound applications in the emergency department and intensive care unit—A review. Curr Cardiol Rev 2012; 8:98–108 26. Melamed R, Sprenkle MD, Ulstad VK, et al: Assessment of left ventricular function by intensivists using hand-held echocardiography. Chest 2009; 135:1416–1420
APPENDIX 1. Case Report Form
C. Other Cardiac function (arrhythmia, chemotherapy, transplant, other) Pulmonary hypertension On extracorporeal membrane oxygenator Rule out thrombus Rule out endocarditis Volume status of the patient/ventricular filling
INDICATIONS A. Rule out heart disease Low output/poor perfusion/acidosis/shock Murmur Cyanosis Abnormal chest radiograph Respiratory distress Syndrome Other B. Known heart disease: Rule out bad hemodynamic change Low output/acidosis/shock Change in murmur Cyanosis Abnormal chest radiograph Respiratory distress Ductal patency (systemic blood flow/pulmonary blood flow) Other
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OUTCOMES A. Echo-confirmed suspected condition (Y/N) B. Negative for condition suspected C. Incidental new finding (Y/N) Required/did not require immediate attention (Y/N) D. Change in management (Y/N) Type of change
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