Monitoring in pediatric cardiac critical care: a worldwide perspective

Right Atrial Lines as Primary Access for Postoperative Pediatric Cardiac Patients

To characterize the use of right atrial lines (RALs) as primary access in the postoperative care of neonatal and pediatric patients after cardiothoracic surgery and to identify risk factors associated with RAL complications. Observational retrospective cohort study in pediatric cardiac patients who underwent RAL placement in a tertiary children's hospital from January 2011 through June 2018. A total of 692 children with congenital heart disease underwent 815 RAL placements during the same or subsequent cardiothoracic surgeries during the study period. Median age and weight were 22 days (IQR 7-134) and 3.6 kg (IQR 3.1-5.3), respectively. Neonates accounted for 53.5% of patients and those with single-ventricle physiology were 35.4%. Palliation surgery (shunts, cavo-pulmonary connections, hybrid procedures, and pulmonary artery bandings) accounted for 38%. Survival to hospital discharge was 95.5%. Median RAL duration was 11 days (IQR 7-19) with a median RAL removal to hospital discharge time of 0 days (IQR 0-3). Thrombosis and migration were the most prevalent complications (1.7% each), followed by malfunction (1.4%) and infection (0.7%). Adverse events associated with complications were seen in 12 (1.4%) of these RAL placements: decrease in hemoglobin (n = 1), tamponade requiring pericardiocentesis (n = 3), pleural effusion requiring chest tube (n = 2), and need for antimicrobials (n = 6). Multivariable logistic regression showed that RAL duration (OR 1.01, p = 0.006) and palliation surgery (OR 2.38, p = 0.015) were significant and independent factors for complications. The use of RALs as primary access in postoperative pediatric cardiac patients seems to be feasible and safe. Our overall incidence of complications from prolonged use of RALs remained similar or lower to that reported with short-term use of these lines. While RAL duration and palliation surgeries seemed to be associated with complications, severity of illness could be a confounding factor. A prospective assessment of RAL complications may improve outcomes in this medically complex population.

Comparison of Invasive and Oscillometric Blood Pressure Measurement in Obese and Nonobese Children

BACKGROUND

Obesity and hypertension are public health priorities, with obesity considered to be a potential cause of hypertension. Accurate blood pressure (BP) determination is required and often obtained by automated oscillometric cuff devices. We sought to determine the correlation of oscillometric measurement in children, and if obesity was associated with worse correlation between methods than nonobese children.

METHODS

Retrospective matched case-controlled study of 100 obese (97-99th percentile) and 100 nonobese (25-70th percentile) children after cardiac surgery with simultaneous systolic, diastolic, and mean invasive and oscillometric measurements. Matching was 1:1 for age, sex, race, and Risk Adjustment for Congenital Heart Surgery-1 score. Intraclass correlation coefficients and Bland-Altman plots were used to determine agreement with 0.75 as threshold.

RESULTS

Median age was 13 years (10-15). Agreement was low for systolic (0.65 and 0.61), diastolic (0.68 and 0.61), and mean measurements (0.73 and 0.69) (obese/nonobese). Bland-Altman plots demonstrated oscillometric BP measurements underestimated systolic hypertension (oscillometric readings lower than intra-arterial). Oscillometric measurements underestimated hypotension (systolic oscillometric measurements were higher than intra-arterial). This occurred in obese and nonobese patients. Correlation of oscillometric measurements was similar for nonobese and obese patients.

CONCLUSIONS

In this first ever study of simultaneous BP measurement by oscillometric vs. intra-arterial in obese and nonobese children, correlation is below accepted norms. The correlation of oscillometric cuff measurements is not affected by habitus in children. There is less correlation between oscillometric measurements and intra-arterial measurements during hypertension or hypotension. Healthcare providers should be aware of the limitations of oscillometric measurements.

Transthoracic intracardiac catheters in perioperative management of pediatric cardiac surgery patients: a single-center experience

BACKGROUND

Transthoracic intracardiac catheters inserted under direct vision in the pulmonary artery and left atrium during cardiac surgery play major roles in the management of patients with complex congenital heart disease. We aimed to analyze the utility of transthoracic intracardiac catheters in the perioperative management of pediatric cardiac surgery patients and review catheter-related morbidity.

METHODS

The computerized register of all pediatric cardiac surgery patients in whom transthoracic intracardiac catheters were inserted from 2012 to 2019 in a tertiary referral center were reviewed.

RESULTS

Transthoracic pulmonary artery and left atrial catheters were inserted in 89 and 71 patients, respectively. The most common indications for pulmonary artery and left atrial catheters were total anomalous pulmonary venous connection (52%) and total cavopulmonary connection (58%) respectively. The most common reason for elevated pulmonary artery and left atrial pressure after cardiopulmonary bypass was left ventricular dysfunction. Transthoracic pulmonary artery catheters helped in diagnosing pulmonary hypertensive crisis (29%), surgical decision-making (14%), and ventilator therapy (16%). Left atrial catheters helped in the diagnosis of left ventricular dysfunction (54%). The incidence of morbidity was 8.9% for transthoracic pulmonary artery catheters and 9.8% for left atrial catheters.

CONCLUSION

Transthoracic pulmonary artery catheters help in the diagnosis and management of pulmonary hypertensive crisis, for making perioperative surgical decisions, and during ventilator therapy. Transthoracic left atrial catheters help in the diagnosis of left ventricular dysfunction in the perioperative period. The diagnostic and treatment benefits provided by transthoracic intracardiac catheters outweigh the minor adverse events, supporting their continued use in the perioperative period.

Image-Guided Resuscitation With Limited Transthoracic Echocardiogram in Pediatric Trauma Patients

INTRODUCTION

Limited transthoracic echocardiogram (LTTE) has been shown to be a useful tool in guiding resuscitation in adult trauma patients. Our hypothesis is that image-guided resuscitation in pediatric trauma patients with LTTE is feasible.

METHODS

A retrospective chart review was performed on highest level pediatric trauma alerts (age 18 years or younger) at our level I trauma center during a 6-month period. Patients were divided into 2 groups as follows: those who had LTTE performed (LTTE group) and those who did not have LTTE performed (non-LTTE group).

RESULTS

A total of 31 charts were reviewed; 4 patients were excluded because they died on arrival to the emergency department. Fourteen patients had LTTE performed (LTTE group); 13 patients did not have LTTE performed (non-LTTE group). There was no difference in mechanism of injury, age, injury severity score, weight, or intensive care unit admission between the groups. The LTTE group received significantly less intravenous fluid than the non-LTTE group (1.2 vs 2.3 L, P = 0.0013).Within the LTTE group, 8 patients had "full" inferior vena cava (IVC) and 6 patients had "empty" IVC. There was no difference in injury severity score between these subgroups (P = 0.1018). Less fluid was given in the group labeled with full IVC [1.1 L (0.8-1.2)] than the group with empty IVC [2.4 L (1.7-2.6)], P = 0.0005. Four of the 6 patients with "empty" IVC had a confirmed source of bleeding.

CONCLUSIONS

Limited transthoracic echocardiogram can limit the amount of unnecessary crystalloid resuscitation given to pediatric trauma patients who are not hypovolemic.

Transthoracic intracardiac catheters in pediatric cardiac patients: A single-center experience

BACKGROUND

Transthoracic intracardiac catheters are frequently inserted in children during congenital heart surgery for monitoring and vascular access purposes. Their use entails a small potential risk.

AIM

We aimed to evaluate both catheter-associated morbidities related to maintenance and removal of transthoracic intracardiac catheters in pediatric cardiac patients, and predictors for catheter-associated adverse events.

METHODS

Single-center retrospective cohort study of prospectively collected data of children aged 0-14 years receiving a transthoracic intracardiac catheter inserted in the operating room during 7 consecutive years at the University Children's Hospital Zurich.

RESULTS

A total of 115 transthoracic intracardiac catheters were placed in 112 patients: 45 right atrial, 68 left atrial, and 2 pulmonary artery catheters. Five catheters (4.3%) had to be removed due to catheter-associated adverse events (infection, 2; nonfunction, 2; and leakage 1). After catheter removal, 19% of patients suffered adverse events, these were minor in 16 (14%) and serious in 6 (5.1%) (symptomatic bleeding in four (3.5%) patients, pericardial tamponade leading to death in one (0.8%), and tension pneumothorax in one (0.8%)). Catheter position in the right atrium and the need for platelet transfusion prior to removal were risk factors for adverse events.

CONCLUSIONS

Transthoracic intracardiac catheters are useful in the management of specific patient groups with complex congenital heart defects. Adverse events do occur; most of them do not require intervention. The insertion technique plays an important role in avoiding adverse events. Strict guidelines for the use and removal of transthoracic intracardiac catheters are required. Low platelet count should delay catheter removal. The wealth of information and therapeutic options offered by these catheters appear to outweigh the associated potential adverse events in this specific patient group.

Echocardiography in PICU: when the heart sees what is invisible to the eye

OBJECTIVE

Echocardiography has become an indispensable bedside diagnostic tool in the realm of pediatric intensive care units (PICU). It has proven to be an influential factor in the formula of clinical decision-making. This study aimed to delineate the impact of echocardiography on the management of critically ill pediatric patients in the PICU at Sultan Qaboos University Hospital, Oman.

METHOD

This was a retrospective cohort study conducted in a five-bed PICU. Patients admitted to the PICU from January of 2011 to December of 2012 were reviewed. Those who have undergone bedside echocardiography during their ICU stay were recruited. Electronic patient record was used as data source.

RESULTS

Over a-24-month period, 424 patients were admitted in this PICU. One hundred and one clinically indicated transthoracic echocardiograms were performed. 81.8% of these presented new findings (n=82) that significantly impacted the clinical decision of patient management, namely, alteration in drug therapy and procedure, whereas no difference in the management was yielded in the remaining 17.8% of the studied cases.

CONCLUSIONS

Echocardiography had a significant impact on the management of PICU patients. Such salutary effect was consequently reflected on the outcome. Pediatric intensivists are encouraged to acquire such bedside skill.

Transthoracic echocardiography in pediatric intensive care: impact on medical and surgical management

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 indication 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 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.

Focused cardiac ultrasound: a training course for pediatric intensivists and emergency physicians

BACKGROUND

Focused echocardiographic examinations performed by intensivists and emergency room physicians can be a valuable tool for diagnosing and managing the hemodynamic status of critically ill children. The aim of this study was to evaluate the learning curve achieved using a theoretical and practical training program designed to enable pediatric intensivists and emergency physicians to conduct targeted echocardiograms.

METHODS

Theoretical and practical training sessions were conducted with 16 pediatric intensivist/emergency room physicians. The program included qualitative analyses of the left ventricular (LV) and right ventricular (RV) functions, evaluation of pericardial effusion/cardiac tamponade and valvular regurgitation and measurements of the distensibility index of the inferior vena cava (dIVC), ejection fraction (EF) and cardiac index (CI). The practical training sessions were conducted in the intensive care unit; each student performed 24 echocardiograms. The students in training were evaluated in a practical manner, and the results were compared with the corresponding examinations performed by experienced echocardiographers. The evaluations occurred after 8, 16 and 24 practical examinations.

RESULTS

The concordance rates between the students and echocardiographers in the subjective analysis of the LV function were 81.3% at the first evaluation, 96.9% at the second evaluation and 100% at the third evaluation (p < 0.001). For the dIVC, we observed a concordance of 46.7% at the first evaluation, 90.3% at the second evaluation and 87.5% at the third evaluation (p = 0.004). The means of the differences between the students' and echocardiographers' measurements of the EF and CI were 7% and 0.56 L/min/m2, respectively, after the third stage of training.

CONCLUSIONS

The proposed training was demonstrated to be sufficient for enabling pediatric physicians to analyze subjective LV function and to measure dIVC, EF and CI. This training course should facilitate the design of other echocardiography training courses that could be implemented in medical residency programs to improve these physicians' technical skills and the care of critically ill patients.

Validation of an ultrasound dilution technology for cardiac output measurement and shunt detection in infants and children

OBJECTIVE

To validate cardiac output measurements by ultrasound dilution technology (COstatus monitor) against those obtained by a transit-time ultrasound technology with a perivascular flow probe and to investigate ultrasound dilution ability to estimate pulmonary to systemic blood flow ratio in children.

DESIGN

Prospective observational clinical trial.

SETTING

Pediatric cardiac operating theater in a university hospital.

MATERIAL AND METHODS

In 21 children (6.1 ± 2.6 kg, mean ± SD) undergoing heart surgery, cardiac output was simultaneously recorded by ultrasound dilution (extracorporeal arteriovenous loop connected to existing arterial and central venous catheters) and a transit-time ultrasound probe applied to the ascending aorta, and when possible, the main pulmonary artery. The pulmonary to systemic blood flow ratio estimated from ultrasound dilution curve analysis was compared with that estimated from transit-time ultrasound technology.

RESULTS

Bland-Altman analysis of the whole cohort (90 pairs, before and after surgery) showed a bias between transit-time ultrasound (1.01 ± 0.47 L/min) and ultrasound dilution technology (1.03 ± 0.51 L/min) of -0.02 L/min, limits of agreement -0.3 to 0.3 L/min, and percentage error of 31%. In children with no residual shunts, the bias was -0.04 L/min, limits of agreement -0.28 to 0.2 L/min, and percentage error 19%. The pooled co efficient of variation was for the whole cohort 3.5% (transit-time ultrasound) and 6.3% (ultrasound dilution), and in children without shunt, it was 2.9% (transit-time ultrasound) and 4% (ultrasound dilution), respectively. Ultrasound dilution identified the presence of shunts (pulmonary to systemic blood flow ≠ 1) with a sensitivity of 100% and a specificity of 92%. Mean pulmonary to systemic blood flow ratio by transit-time ultrasound was 2.6 ± 1.0 and by ultrasound dilution 2.2 ± 0.7 (not significant).

CONCLUSION

The COstatus monitor is a reliable technique to measure cardiac output in children with high sensitivity and specificity for detecting the presence of shunts.