Cardiac parameters in children recovered from acute illness as measured by electrical cardiometry and comparisons to the literature

Comparison of heart rate and cardiac output of VVI pacemaker settings in patients with atrial fibrillation with bradycardia

BACKGROUND

While most VVI pacemakers in bradycardic patients are set to a low limit of 60/min, the optimal lower limit rate for VVI pacemakers in atrial fibrillation has not been established. Although an increase in heart rate within the normal range in the setting of a VVI pacemaker might be expected to lead to an increase in cardiac output with the shortening of the diastolic time, the changes in cardiac output at different pacemaker settings have not been fully clarified.

METHODS

We included 11 patients with bradycardic atrial fibrillation who had VVI pacemakers implanted. Stroke volume was measured using the electrical cardiometry method (AESCULONⓇ mini; Osypka Medical) without pacing and at ventricular pacings of 60, 70, 80, and 90/min.

RESULTS

Stroke volume decreased stepwise at ventricular pacing rates of 60, 70, 80, and 90/min (63.6 ± 11.2, 61.9 ± 10.6, 59.3 ± 12.2, and 57.5 ± 12.2 mL, p < .001), but cardiac output increased (3.81 ± 0.67, 4.33 ± 0.74, 4.74 ± 0.97, and 5.17 ± 1.09 L/min, p < .001). The rate of increase in cardiac output at a pacing rate of 70/min compared to 60/min correlated with left ventricular end-systolic volume (r = 0.711, p = .014).

CONCLUSIONS

Cardiac output increased at a pacing rate of 70 compared to 60 in bradycardic atrial fibrillation patients, and the rate of increase in cardiac output was greater in those with larger left ventricular end-systolic volume.

Usefulness of Optimization of Interventricular Delay Using an Electrical Cardiometry Method in Patients with Cardiac Resynchronization Therapy Implantation

There are no studies examining interventricular (VV) delay optimization by an electrical cardiometry method in relation to subsequent cardiac function in cardiac resynchronization therapy (CRT) -implanted patients. This study aimed to compare the VV delay in CRT-implanted patients by the dp/dt and electrical cardiometry and to examine the optimization of VV delay and improvement of cardiac function. We examined 19 consecutive CRT-implanted patients. The protocol included biventricular stimulation with either simultaneous or sequential pacing, and we evaluated systolic volume (SV) using an electrical cardiometry and the dp/dt of the left ventricle. The optimal VV delay was determined by the maximum SV using the electrical cardiometry. Two groups were defined, those whose increase in SV was at or above the median and those whose SV increase was below the median; changes in left ventricular ejection fraction (LVEF). The correlation between the VV delay optimized by the electrical cardiometry and dp/dt methods was high (R = 0.61, P = 0.006). Compared to the baseline SV (43.4 mL), the SV increased to 47.8 mL with simultaneous biventricular pacing (versus baseline P = 0.008) and further increased to 49.8 mL with optimized VV delay (versus simultaneous biventricular pacing P = 0.020). LVEF after 6 months significantly improved in the above-median SV increase group (37.6 versus 28.2%, P = 0.041), but not in the below-median SV increase group (26.5 versus 26.5%, P = 0.985). In conclusion, the optimal VV delay by electrical cardiometry method was almost concordant with that by the dp/dt method. Cardiac function significantly improved in the group with the above-median SV increase.

Comparison of Bioimpedance Versus Pulse Contour Analysis for Intraoperative Cardiac Index Monitoring in Patients Undergoing Kidney Transplantation

Background

Cardiac index (CI; cardiac output indexed to body surface area) is routinely measured during kidney transplant surgery. Bioimpedance cardiometry is a transthoracic impedance as the non-invasive alternative for hemodynamic monitoring, using semi-invasive uncalibrated pulse wave or contour (UPC) analysis.

Objectives

We performed a cross-sectional observational study on 50 kidney transplant patients to compare the CI measurement agreement, concordance rate, and trending ability between bioimpedance and UPC analysis.

Methods

For each patient, CI was measured by bioimpedance analysis (ICON^TM) and UPC analysis (EV1000^TM) devices at three time points: after induction, during incision, and at reperfusion. The device measurement accuracy was assessed by the bias value, limit of agreement (LoA), and percentage error (PE) using Bland-Altman analyses. Trending ability was assessed by angular bias and polar concordance through four-quadrant and polar plot analyses.

Results

From each time point and pooled measurement, the correlation coefficients were 0.267, 0.327, 0.321, and 0.348. Bland-Altman analyses showed mean bias values of 1.18, 1.06, 1.48, and 1.30, LoA of -1.35 to 3.72, -1.39 to 3.51, -1.07 to 4.04, and -1.17 to 3.78, and PE of 82.21, 78.50, 68.74, and 74.58%, respectively. Polar plot analyses revealed angular bias values of -10.37º, -15.01º, -18.68º, and -12.62º, with radial LoA of 89.79º, 85.86º, 83.38º, and 87.82º, respectively. The four-quadrant plot concordance rates were 70.77, 67.35, 65.90, and 69.79%. These analyses showed poor agreement, weak concordance, and low trending ability of bioimpedance cardiometry to UPC analysis.

Conclusions

Bioimpedance and UPC analysis for CI measurements were not interchangeable in patients undergoing kidney transplant surgery. Cardiac index monitoring using bioimpedance cardiometry during kidney transplantation should be interpreted cautiously because it showed poor reliability due to low accuracy, precision, and trending ability for CI measurement.

Electrocardiometry for Hemodynamic Categorization and Assessment of Fluid Responsiveness in Pediatric Septic Shock: A Pilot Observational Study

Aim

To evaluate the utility of noninvasive electrocardiometry (ICON®) for hemodynamic categorization and assessment of fluid responsiveness in pediatric septic shock.

Materials and methods

Pilot prospective observational study in a 12-bedded tertiary pediatric intensive care unit (PICU) in children aged between 2 months and 16 years with unresolved septic shock after a 20 mL/kg fluid bolus. Those with cardiac index (CI) <3.3 L/min/m² and systemic vascular resistance index (SVRI) >1600 dyn sec/cm⁵/m² were classified as vasoconstrictive shock–electrocardiometry (VCEC) and those with CI >5.5 L/min/m² and SVRI <1000 dyn sec/cm⁵/m² as vasodilated shock–electrocardiometry (VDEC). Fluid responsiveness was defined as a 10% increase in CI with a 20 mL/kg fluid bolus. Sepsis-induced myocardial dysfunction (SMD) was diagnosed on echocardiography. Outcomes studied included clinical shock resolution, length of PICU stay, and mortality.

Results

Thirty children were enrolled over 6 months with a median (interquartile range) age and pediatric risk of mortality (PRISM) III score of 87(21,108) months and 6.75(1.5,8.25), respectively; 14(46.6%) were boys and 4(13.3%) died. Clinically, 19(63.3%) children had cold shock and 11(36.7%) had warm shock; however, 16(53.3%) children had VDEC (including five with clinical cold shock) and 14(46.7%) had VCEC using electrocardiometry. Fluid responsiveness was seen in 16(53.3%) children, 10 in the VCEC group and 6 in the VDEC group. In the VCEC group, the responders had a significant rise in CI and a fall in SVRI, while the responders in the VDEC group had a significant rise in CI and SVRI. Fluid responders, compared to nonresponders, had a significantly higher stroke volume variation (SVV) before fluid bolus (24.1 ± 5.2% vs. 18.2 ± 3.5%, p < 0.001) and a higher reduction in SVV after fluid bolus (10.0 ± 2.8% vs. 6.0 ± 4.5%, p = 0.006), higher lactate clearance (p = 0.03) and lower vasoactive-inotropic score (p = 0.04) at 6 hours, higher percentage of clinical shock resolution at 6 (p = 0.01) and 12 hours (p = 0.01), and lesser mortality (p = 0.002). Five (16.6%) children with VCEC had SMD and were less fluid responsive (p = 0.04) with higher mortality (p = 0.01) compared to those without SMD.

Conclusions and clinical significance

Continuous, noninvasive hemodynamic monitoring using electrocardiometry permits hemodynamic categorization and assessment of fluid responsiveness in pediatric septic shock. This may provide real-time guidance for optimal interventions, and thus, improve the outcomes.

How to cite this article

Rao SS, Reddy M, Lalitha AV, Ghosh S. Electrocardiometry for Hemodynamic Categorization and Assessment of Fluid Responsiveness in Pediatric Septic Shock: A Pilot Observational Study. Indian J Crit Care Med 2021;25(2):185–192.

The accuracy of electrical cardiometry for the noninvasive determination of cardiac output before and after lung surgeries compared to transthoracic echocardiography

Background:

The anatomical changes associated with lung surgeries may decrease cardiac output and heart function. Therefore, monitoring of cardiac output (CO) is of significant value in these patients for clinical decision-making.

Objective:

This study is to evaluate the reliability of electrical cardiometry (EC) for the noninvasive continuous determination of CO after lobectomy or pneumonectomy compared to transthoracic echocardiography (TTE).

Patients and Methods:

This study was carried out on 60 patients, age ≥18 years scheduled for elective lung surgery (lobectomy or pneumonectomy). All patients underwent simultaneous measurement by EC using the ICON_ device and by TTE by measuring left ventricle outflow tract diameter (LVOT) and velocity time integral (VTI). Heart rate (HR), systolic and diastolic blood pressure (SBP and DBP), stroke volume (SV), stroke volume index (SVI), CO, and cardiac index (CI) were measured 1 day before the surgery and 7 days after the surgery.

Results:

There was no significant difference between TTE and EC regarding preoperative and postoperative HR, SV, SVI, CO, and CI. There was a strong positive correlation between TTE and EC as regard preoperative and postoperative HR, SV, SVI, CO, and CI. Bland and Altman analysis showed low bias with accepted limits of agreement of HR, SV, SVI, CO, and CI. Postoperative readings showed a significant increase in HR and a significant decrease in SV and CO (either by TTE or EC), SBP, and DBP as compared to preoperative reading.

Conclusion:

Compared to the TTE, EC provides accurate and reliable CO, SV, and HR measurements before and even after lung surgeries.

Use of a Non-invasive Cardiac Output Measurement in a Patient with Low-output Dilated Cardiomyopathy

A 49-year-old man was diagnosed with acute cardiac insufficiency based on evidence of congestive heart failure. The non-invasive measurement of the cardiac output using an AESCULON^® mini showed low cardiac output (CO, 3.9 L/min). We administered an intravenous diuretic for cardiac edema and dobutamine drip for low cardiac output. Soon after starting dobutamine at 3.2 γ (microg/kg/min), the CO improved to 6.8 L/min. Combination therapy of diuretic and dobutamine resolved the heart failure. CO measurement by an AESCULON^® mini was safe, cost-effective, and convenient. Data output correlates with the CO by Swan-Ganz catheterization. The non-invasive measurement of the CO permitted a smooth recovery without recurrence in this patient.

Non-invasive measurement of cardiac output in children with repaired coarctation of the aorta using electrical cardiometry compared to transthoracic Doppler echocardiography

OBJECTIVE

To evaluate the equivalence of the ICON^® electrical cardiometry (EC) haemodynamic monitor to measure cardiac output (CO) relative to transthoracic Doppler echocardiography (TTE) in paediatric patients with repaired coarctation of the aorta (CoA).

APPROACH

A group of n  =  28 CoA patients and n  =  27 matched controls were enrolled. EC and TTE were performed synchronously on each participant and CO measurements compared using linear regression and Bland-Altman analysis. The CoA group was further subdivided into two groups, with n  =  10 and without n  =  18 increased left ventricular outflow tract velocity (iLVOTv) for comparison.

MAIN RESULTS

CO measurements from EC and TTE in controls showed a strong correlation (R  =  0.80, p  <  0.001) and an acceptable percentage error (PE) of 28.1%. However, combining CoA and control groups revealed a moderate correlation (R  =  0.57, p  <  0.001) and a poor PE (44.2%). We suspected that the CO in a subset of CoA participants with iLVOTv was overestimated by TTE. Excluding the iLVOTv CoA participants improved the correlation (R  =  0.77, p  <  0.001) and resulted in an acceptable PE of 31.2%.

SIGNIFICANCE

CO measurements in paediatric CoA patients in the absence of iLVOTv are clinically equivalent between EC and TTE. The presence of iLVOTv may impact the accuracy of CO measurement by TTE, but not EC.

Accuracy, Precision, and Trending Ability of Electrical Cardiometry Cardiac Index versus Continuous Pulmonary Artery Thermodilution Method: A Prospective, Observational Study

Introduction

Evaluation of accuracy, precision, and trending ability of cardiac index (CI) measurements using the Aesculon™ bioimpedance electrical cardiometry (Aesc) compared to the continuous pulmonary artery thermodilution catheter (PAC) technique before, during, and after cardiac surgery.

Methods

A prospective observational study with fifty patients with ASA 3-4. At six time points (T), measurements of CI simultaneously by continuous cardiac output pulmonary thermodilution and thoracic bioimpedance and standard hemodynamics were performed. Analysis was performed using Bland-Altman, four-quadrant plot, and polar plot methodology.

Results

CI obtained with pulmonary artery thermodilution and thoracic bioimpedance ranged from 1.00 to 6.75 L min⁻¹ and 0.93 to 7.25 L min⁻¹, respectively. Bland-Altman analysis showed a bias between CI_BIO and CI_PAC of 0.52 liters min⁻¹ m⁻², with LOA of [−2.2; 1.1] liters min⁻¹ m⁻². Percentage error between the two techniques was above 30% at every time point. Polar plot methodology and 4-quadrant analysis showed poor trending ability. Skin incision had no effect on the results.

Conclusion

CI obtained by continuous PAC and CI obtained by Aesculon bioimpedance are not interchangeable in cardiac surgical patients. No effects of skin incision were found. International clinical trial registration number is ISRCTN26732484.

Electrical Cardiometry: A Reliable Solution to Cardiac Output Estimation in Children With Structural Heart Disease

OBJECTIVE

Comparison of cardiac output (CO) obtained using electric cardiometry (EC) and pulmonary artery catheterization (PAC) in pediatric patients with congenital structural heart disease.

DESIGN

Prospective, observational study.

SETTING

A tertiary hospital.

PARTICIPANTS

The study comprised 50 patients scheduled to undergo cardiac catheterization.

INTERVENTIONS

CO data triplets were obtained simultaneously from the cardiometry device ICON (Osypka Medical, Berlin, Germany) and PAC at the following predefined time points-(1) T1: 5 minutes after arterial and venous cannulation and (2) T2: 5 minutes postprocedure; the average of the 3 readings was calculated. Reliability analysis and Bland-Altman analysis were performed to determine the limits of agreement, mean bias, and accuracy of the CO measured with EC.

MEASUREMENTS AND MAIN RESULTS

The measured EC-cardiac index 4.22 (3.84-4.60) L/min/m² and PAC-cardiac index 4.26 (3.67-4.67) L/min/m² were statistically insignificant (p value>0.05) at T1. Bland-Altman analysis revealed a mean bias of 0.0051 L/min/m² and precision limits of±0.4927 L/min/m². The intraclass correlation coefficient was 0.789 and Cronbach's alpha was 0.652, indicating good reproducibility and internal consistency between the two techniques. Postcatheterization analysis also revealed strong agreement and reliability between the two techniques.

CONCLUSIONS

This study demonstrated that cardiac indices measured in children with a variety of structural heart diseases using EC reliably represent absolute values obtained using PAC. EC technology is simple and easy to use and offers noninvasive beat-to-beat tracking of CO and other hemodynamic parameters in children with structurally abnormal hearts.

Hemodynamic reference for neonates of different age and weight: a pilot study with electrical cardiometry

OBJECTIVE

Electrical cardiometry (EC) is an impedance-based monitor that provides noninvasive, real-time hemodynamic assessment. However, the reference values for neonates have not been established.

STUDY DESIGN

EC (Aesculon) was applied to hemodynamically stable preterm and term infants. Hemodynamic variables included cardiac output (CO), cardiac index (CI), stroke volume (SV) and heart rate (HR). Their gestational age (GA), weight and body surface area (BSA) were recorded.

RESULTS

A total of 280 neonates were studied. Their GA ranged from 26(5/7) to 41(4/7) weeks, weight 800 to 4420 g and BSA 0.07 to 0.26 m(2). CO was positively correlated to GA, weight and BSA (r=0.681, 0.822, 0.830, respectively; all P<0.001). Using regression analysis, CO was most significantly correlated to BSA. Mean CI was 2.55±0.37 l min(-1) per m(2).

CONCLUSION

Hemodynamic reference by EC is notably distinct among neonates of diverse maturity. CO is most closely correlated to BSA.

Age-related incidence of desaturation events and the cardiac responses on stroke index, cardiac index, and heart rate measured by continuous bioimpedance noninvasive cardiac output monitoring in infants and children undergoing general anesthesia

STUDY OBJECTIVE

To assess the effects of desaturation on stroke index (SI), cardiac index (CI), and heart rate (HR) using the ICON continuous noninvasive cardiac output monitor in children undergoing general anesthesia.

DESIGN

Retrospective analysis of a prospectively collected data set.

SETTING

Pediatric operating rooms in a tertiary academic medical center.

PATIENTS

Children younger than 20 years who experienced desaturation while undergoing general anesthesia.

INTERVENTION

All records were retrospectively searched for desaturation events defined as a recorded Spo2 ≤ 90%. We compared the data from the prior 4 minutes (baseline) with mild, moderate, and severe levels of desaturation.

MEASUREMENTS

The relationship between Spo2 and percent change in SI, CI, and HR from baseline was assessed using a generalized linear model with repeated measures and the least-squares method.

MAIN RESULTS

Data from 446 patients were reviewed; 38 events were eligible for analysis after exclusions. There were significant decreases in SI at all saturation ranges below 95%: -6.5% (P < .001) for 85%-95%, -8.9% (P = .002) for 71%-84%, and -11% (P < .001) for ≤70%. Based on the result from the regression, Spo2 was associated with change in SI with borderline significance (P = .053) but not that of HR and CI. There was a strong relationship to desaturation events with young age (P < .001), particularly infants younger than 6 months.

CONCLUSION

Events associated with desaturation in children under general anesthesia were significantly associated with decreased SI with a greater effect with lower saturation nadirs. It is unclear if other concurrent events could have also contributed to adverse hemodynamic responses during desaturation. In most children, a compensatory increase in HR generally offsets concurrent decreases in CI. It would appear that bradycardia is a late manifestation of hypoxemia.

The Use of Epinephrine in Caudal Anesthesia Increases Stroke Volume and Cardiac Output in Children

BACKGROUND AND OBJECTIVES

Caudal anesthesia is a common and effective regional anesthesia technique in pediatric patients. The addition of epinephrine to local anesthetics in caudal anesthesia is a frequent practice; however, changes in hemodynamic and cardiac parameters produced by epinephrine in caudal anesthesia are not well studied. Using data collected with the ICON noninvasive cardiac output monitor, we examined the hemodynamic changes associated with the administration of epinephrine containing local anesthetics during caudal anesthesia in children.

METHODS

We performed a retrospective analysis of 40 patients who received caudal anesthesia among 402 patients from whom we prospectively collected continuous noninvasive cardiac output data using the ICON monitor, which estimates cardiac output by measuring changes in thoracic bioimpedance during the cardiac cycle. Twenty-three children received epinephrine with local anesthetic (ELA), and 17 children received only local anesthetic (OLA) in their caudal blocks. We compared heart rate (HR), stroke volume (SV), cardiac output (CO), and cardiac index (CI) changes from baseline before caudal injection to 1-minute intervals over 15 minutes after caudal injection for both ELA and OLA groups (Table, Supplemental Digital Content 1, http://links.lww.com/AAP/A179). We also performed subgroup analysis of the same parameters comparing both ELA and OLA groups in infants younger than 6 months and in children 6 months or older.

RESULTS

Stroke volume, CO, and CI are significantly increased after caudal injection in the ELA group compared with baseline values at caudal injection time. Conversely, there were no statistically significant changes in SV, CO, and CI in the OLA group. There were no significant HR or blood pressure changes observed in either the ELA or OLA group within 15 minutes compared with baseline caudal injection time. In infants younger than 6 months, no significant differences were found in HR, SV, and CI in children in the ELA group compared with the OLA group. In children 6 months or older, SV and CI increased significantly in the ELA group compared with the OLA group.

CONCLUSIONS

Epinephrine added to local anesthetic injected for caudal anesthesia produces significant increases in SV, CO, and CI in children. Stroke volume and CI changes from epinephrine added to local anesthetic for caudal anesthesia seem to take place only in children 6 months or older.

Hemodynamic alterations recorded by electrical cardiometry during ligation of ductus arteriosus in preterm infants

This is a prospective study using non-invasive electrical cardiometry to measure hemodynamic changes during surgical ligation of patent ductus arteriosus (PDA) in very low birth weight (VLBW, ≤1500 g) infants. The aims of this study were to examine hemodynamic aberration caused by abrupt closure of a ductal shunting and to define factors that affect hemodynamic changes. Simultaneous measurements of heart rate (HR), stroke volume (SV), cardiac output (CO), and systemic vascular resistance (SVR) were collected at ten time points: 1 h prior to anesthesia, at the beginning of anesthesia, starting of surgery, immediately after PDA being ligated, and 1 h followed by 6, 12, 18, 24, and 48 h after the surgery. Thirty infants with gestational age of 27.7 ± 2.0 weeks and birth weight of 929 ± 280 g were studied. Upon sudden termination of ductal shunting, there was a significant decline in CO to 73 % of presurgery baseline. The deterioration in CO was associated with a decreased SV rather than HR. At the same time, there was an increase of SVR following ductal ligation. Magnitude of CO and SV reduction were higher in smaller infants (≤1 kg), and recovery was to a lesser degree in infants with more severe PDA.

CONCLUSION

Reduced stroke volume and elevated vascular resistance contribute to the major hemodynamic aberrations in VLBW infants receiving PDA ligation surgery.

Continuous noninvasive cardiac output in children: is this the next generation of operating room monitors? Initial experience in 402 pediatric patients

BACKGROUND

Electrical Cardiometry(™) (EC) estimates cardiac parameters by measuring changes in thoracic electrical bioimpedance during the cardiac cycle. The ICON(®), using four electrocardiogram electrodes (EKG), estimates the maximum rate of change of impedance to peak aortic blood acceleration (based on the premise that red blood cells change from random orientation during diastole (high impedance) to an aligned state during systole (low impedance)).

OBJECTIVE

To determine whether continuous cardiac output (CO) data provide additional information to current anesthesia monitors that is useful to practitioners.

METHODS

After IRB approval and verbal consent, 402 children were enrolled. Data were uploaded to our anesthesia record at one-minute intervals. Ten-second measurements (averaged over the previous 20 heart beats) were downloaded to separate files for later comparison with routine OR monitors.

RESULTS

Data from 374 were in the final cohort (loss of signal or improper lead placement); 292,012 measurements during 58,049 min of anesthesia were made in these children (1 day to 19 years and 1 to 107 kg). Four events had a ≥25% reduction in cardiac index at least 1 min before a clinically important change in other monitored parameters; 18 events in 14 children confirmed manifestations of other hemodynamic measures; eight events may have represented artifacts because the observed measurements did not seem to fit the clinical parameters of the other monitors; three other events documented decreased stroke index with extreme tachycardia.

CONCLUSIONS

Electrical cardiometry provides real-time cardiovascular information regarding developing hemodynamic events and successfully tracked the rapid response to interventions in children of all sizes. Intervention decisions must be based on the combined data from all monitors and the clinical situation. Our experience suggests that this type of monitor may be an important addition to real-time hemodynamic monitoring.

Cardiac output assessed by non-invasive monitoring is associated with ECG changes in children with critical asthma

The primary aim of this study was to determine changes in CI and SI, if any, in children hospitalized with status asthmatics during the course of treatment as measured by non-invasive EC monitoring. The secondary aim was to determine if there is an association between Abnormal CI (defined as <5 or >95 % tile adjusted for age) and Abnormal ECG (defined as ST waves changes) Non-invasive cardiac output (CO) recordings were obtained daily from admission (Initial) to discharge (Final). Changes in CI and SI measurements were compared using paired t tests or 1-way ANOVA. The association between Abnormal CI on Initial CO recording and Abnormal ECG was analyzed by Fischer's exact test. Data are presented as mean ± SEM with mean differences reported with 95 % confidence interval; p < 0.05 was considered significant. Thirty-five children with critical asthma were analyzed. CI decreased from 6.2 ± 0.2 to 4.5 ± 0.1 [-1.6 (-0.04 to -0.37)] L/min/m(2) during hospitalization. There was no change in SI. There was a significant association between Abnormal Initial CI and Abnormal ECG (p = 0.02). In 11 children requiring prolonged hospitalization CI significantly decreased from 7.2 ± 0.5 to 4.0 ± 0.2 [-3.2 (-4.0 to -2.3)] L/min/m(2) and SI decreased from 51.2 ± 3.8 to 40.3 ± 2.0 [-11.0 (-17.6 to -4.4)] ml/beat/m(2) There was a significant decrease in CI in all children treated for critical asthma. In children that required a prolonged course of treatment, there was also a significant decrease in SI. Abnormal CI at Initial CO recording was associated with ST waves changes on ECG during hospitalization. Future studies are required to determine whether non-invasive CO monitoring can predict which patients are at risk for developing abnormal ECG.

Non-invasive measurement of cardiac output in obese children and adolescents: comparison of electrical cardiometry and transthoracic Doppler echocardiography

The objective of this study was to evaluate the reliability and accuracy of electrical cardiometry (EC) for the noninvasive determination of cardiac output (CO) in obese children and adolescents. We compared these results with those obtained by transthoracic echocardiography. Sixty-four participants underwent simultaneous measurement of CO. Cardiac output was measured by EC using the ICON(®) device. Simultaneously CO was determined by using transthoracic Doppler echocardiography from parasternal long-axis and apical view. The median age was 12.52 years (range 7.9-17.6 years) and 36 (56 %) were female. A strongly significant correlation was found between the COEC and COEcho measurements (p < 0.0001, r = 0.91). Significant correlations were also found between CO and age (r = 0.37, p = 0.002), weight (r = 0.57, p < 0.0001), height (0.60, p < 0.0001) and BMI (r = 0.42, p = 0.001). The mean difference between the two methods (COEC - COEcho) was 0.015 l min(-1). According to the Bland and Altman method, the upper and lower limits of agreement, defined as mean difference ±2 SD, were +1.21 and -0.91 l min(-1), respectively. Compared to the transthoracic Doppler echocardiography, Electrical Cardiometry provides accurate and reliable CO measurements in obese children and adolescents.