Continuous arterial pressure waveform monitoring in pediatric cardiac transplant, cardiomyopathy and pulmonary hypertension patients
ABSTRACT A continuous cardiac output monitor based on arterial pressure waveform (FloTrac/Vigileo; Edwards Lifesciences, Irvine, CA) is now approved for use in adults but not in children. This device is minimally invasive, calculates cardiac output continuously and in real time, and is easy to use. Our study sought to validate the FloTrac with the pulmonary artery catheter (PAC) intermittent thermodilution technique in pediatric cardiac patients.
This was a prospective pilot study comparing cardiac output measurements obtained via the FloTrac and arterial pressure waveform analysis with intermittent thermodilution. Subjects carried the diagnosis of pulmonary hypertension or cardiomyopathy, or were in the postoperative course after orthotopic heart transplantation.
Enrolled in the study were 31 subjects, and 136 data points were obtained. The age range was 8 months to 16 years. The mean body surface area (BSA) was 1.1 m(2). Bland-Altman plots for the mean cardiac outputs of all subjects with a BSA ≥ 1 m(2) showed limits of agreement of -2.7 to 8.0 l/min (± 5.4 l/min). Patients with a BSA ≤ 1 m(2) demonstrated even wider limits of agreement (± 8.5 l/min). The intraclass correlation for the PAC was 0.929 and 0.992 for the FloTrac.
There was poor agreement between the PAC and FloTrac in measuring cardiac output in a population of children with pulmonary hypertension or cardiomyopathy, or after cardiac transplantation. This is in contrast to adult studies published thus far. This suggests that the utility of the FloTrac and measurements obtained from arterial pulse wave analysis in children is uncertain at this time.
[Show abstract] [Hide abstract]
ABSTRACT: The goal of perioperative monitoring is to aid the clinician in optimizing care to achieve the best possible survival with the lowest possible morbidity. Ideally, we would like to have monitoring that can rapidly and accurately identify perturbations in circulatory well-being that would permit timely intervention and allow for restoration before the patient is damaged. The evidence to support the use of our standard monitoring strategies (continuous electrocardiography, blood pressure, central venous pressure, oxygen saturation and capnography) is based on expert opinion, case series, or at best observational studies. While these monitoring parameters will identify life-threatening events, they provide no direct information concerning the oxygen economy of the patient. Nevertheless, they are mandated by professional societies representing specialists in cardiac disease, critical care, and anesthesiology. Additional non-routine monitoring strategies that provide data concerning the body’s oxygen economy, such as venous saturation monitoring and near infrared spectroscopy, have shown promise in prospective observational studies in managing these complex groups of patients. Ideally, high-level evidence would be required before adopting these newer strategies, but in the absence of new funding sources and the challenges of the wide variation in practice patterns between centers, this seems unlikely. The evidence supporting the current standard perioperative monitoring strategies will be reviewed. In addition, evidence supporting non-routine monitoring strategies will be reviewed and their potential for added benefit assessed.Pediatric Cardiac Surgery Annual of the Seminars in Thoracic and Cardiovascular Surgery 01/2014; 17(1):81–90. DOI:10.1053/j.pcsu.2014.01.010
[Show abstract] [Hide abstract]
ABSTRACT: Shock in children is a cause of significant morbidity and mortality. Worldwide, most children dying from shock do not have the opportunity to benefit from advanced critical care support and we recommend to readers the World Health Organization ETAT guidelines . For children treated in the intensive care environment, standard cardiovascular measures such as heart rate, pulse volume, perfusion/capillary refill, core-peripheral temperature gradient and blood pressure along with measures from other organ systems (e.g. urine output and consciousness level) remain vital. All are part of the global assessment of cardiovascular performance and shock in children, and none of the new techniques we describe replace the need for these assessments in critically ill children. Furthermore, evidence is lacking to mandate utilisation of any of the advanced methods we review and they should only be considered as adjuncts to the aforementioned assessments in critical care. We suggest that the optimal monitoring of the shocked child in the ICU, and those developing shock outside the ICU, should include measuring those hemodynamic parameters above together with assessment of preload responsiveness and organ perfusion. Early goal-directed therapy targeting shock reversal remains the consensus best practice position and includes optimization of several haemodynamic parameters . Our personal practice remains to firstly target clearance of raised lactate and venous desaturation, measured by intermittent blood gas analysis and secondly to optimise preload, contractility and afterload guided by Doppler ultrasound or echocardiography. Both can be undertaken in both the emergency department as well as the ICU.03/2015; 1(1). DOI:10.1007/s40746-014-0009-x
[Show abstract] [Hide abstract]
ABSTRACT: The FloTrac/Vigileo™, introduced in 2005, uses arterial pressure waveform analysis to calculate cardiac output (CO) and stroke volume variation (SVV) without external calibration. The aim of this systematic review is to evaluate the performance of the system. Sixty-five full manuscripts on validation of CO measurements in humans, published in English, were retrieved; these included 2234 patients and 44 592 observations. have been analysed according to underlying patient conditions, that is, general critical illness and surgery as normodynamic conditions, cardiac and (post)cardiac surgery as hypodynamic conditions, and liver surgery and sepsis as hyperdynamic conditions, and subsequently released software versions. Eight studies compared SVV with other dynamic indices. CO, bias, precision, %error, correlation, and concordance differed among underlying conditions, subsequent software versions, and their interactions, suggesting increasing accuracy and precision, particularly in hypo- and normodynamic conditions. The bias and the trending capacity remain dependent on (changes in) vascular tone with most recent software. The SVV only moderately agreed with other dynamic indices, although it was helpful in predicting fluid responsiveness in 85% of studies addressing this. Since its introduction, the performance of uncalibrated FloTrac/Vigileo™ has improved particularly in hypo- and normodynamic conditions. A %error at or below 30% with most recent software allows sufficiently accurate and precise CO measurements and trending for routine clinical use in normo- and hypodynamic conditions, in the absence of large changes in vascular tone. The SVV may usefully supplement these measurements.BJA British Journal of Anaesthesia 01/2014; DOI:10.1093/bja/aet429 · 4.35 Impact Factor