Accuracy of a multiparametric score based on pulse wave analysis for prediction of fluid responsiveness: ancillary analysis of an observational study.

PURPOSE: The pressure recording analytical method (PRAM) monitor is a non-invasive pulse contour cardiac output (CO) device that cannot be considered interchangeable with the gold standard for CO estimation. It, however, generates additional hemodynamic indices that need to be evaluated. Our objective was to investigate the performance of a multiparametric predictive score based on a combination of several parameters generated by the PRAM monitor to predict fluid responsiveness. METHODS: Secondary analysis of a prospective observational study from April 2016 to December 2017 in two French teaching hospitals. We included critically ill patients who were monitored by esophageal Doppler monitoring and an invasive arterial line, and received a 250-500 mL crystalloid fluid challenge. The main outcome measure was the predictive score discrimination evaluated by the area under the receiver operating characteristics curve. RESULTS: The three baseline PRAM-derived parameters associated with fluid responsiveness in univariate analysis were pulse pressure variation, cardiac cycle efficiency, and arterial elastance (P < 0.01, P = 0.03, and P < 0.01, respectively). The median [interquartile range] predictive score, calculated after discretization of these parameters according to their optimal threshold value was 3 [2-3] in fluid responders and 1 [1-2] in fluid non-responders, respectively (P < 0.001). The area under the curve of the predictive score was 0.807 (95% confidence interval, 0.662 to 0.909; P < 0.001). CONCLUSION: A multiparametric score combining three parameters generated by the PRAM monitor can predict fluid responsiveness with good positive and negative predictive values in intensive care unit patients.

RéSUMé: OBJECTIF: Le moniteur PRAM (pressure recording analytical method) est un dispositif non invasif de surveillance du débit cardiaque (DC) fondé sur la mesure de contour de l'onde de pouls qui ne peut être considéré comme interchangeable avec la référence de l'estimation du DC. Cependant, ce dispositif génère des indices hémodynamiques supplémentaires qui doivent être évalués. Notre objectif était d'examiner la performance d'un score prédictif multiparamétrique fondé sur une combinaison de plusieurs paramètres générés par le moniteur PRAM afin de prédire la réponse au remplissage volémique. MéTHODE: Analyse secondaire d'une étude observationnelle prospective entre avril 2016 et décembre 2017 dans deux hôpitaux universitaires français. Nous avons inclus des patients en état critique monitorés par un Doppler oesophagien et une ligne artérielle invasive, et ayant reçu un bolus de cristalloïdes de 250­500 mL. Le critère d'évaluation principal était la discrimination du score prédictif telle qu'évaluée par la surface sous la courbe de fonction d'efficacité de l'observateur (ROC). RéSULTATS: Les trois paramètres de base dérivés du PRAM associés à la réponse au remplissage dans l'analyse univariée étaient la variation de pression différentielle, l'efficacité du cycle cardiaque, et l'élastance artérielle (P < 0,01, P = 0,03, et P < 0,01, respectivement). Le score prédictif médian [écart interquartile], calculé après discrétisation de ces paramètres selon leur valeur seuil optimale, était de 3 [2­3] chez les répondeurs au remplissage et de 1 [1­2] chez les non-répondeurs, respectivement (P < 0,001). La surface sous la courbe du score prédictif était de 0,807 (intervalle de confiance 95 %, 0,662 à 0,909; P < 0,001). CONCLUSION: Un score multiparamétrique combinant trois paramètres générés par le moniteur PRAM peut prédire la réponse au remplissage volémique avec de bonnes valeurs prédictives positives et négatives chez les patients à l'unité de soins intensifs.

Monitoring haemodynamic response to fluid-challenge in ICU: comparison of pressure recording analytical method and oesophageal Doppler: A prospective observational study.

BACKGROUND: The ability of the pressure recording analytical method (PRAM) in tracking change in cardiac output (ΔCO) after a fluid challenge in ICU needs to be evaluated with the most contemporary comparison methods recommended by experts. OBJECTIVE: Our objective was to report the trending ability of PRAM in tracking ΔCO after a fluid challenge in ICU and to compare this with oesophageal Doppler monitoring (ODM). DESIGN: Prospective, observational study. SETTING: Hôpital Lariboisière and Hôpital Européen George Pompidou, Paris, France, from April 2016 to December 2017. PATIENTS: Critically ill patients admitted to ICU with monitoring of CO monitored by ODM and invasive arterial pressure. INTERVENTION: ΔCO after fluid challenge was simultaneously registered with ODM and PRAM connected to the arterial line. MAIN OUTCOME MEASURE: Polar statistics (mean angular bias, radial limits of agreement and polar concordance rate) and clinical concordance evaluation (error grid and clinical concordance rate). Predictors of bias were determined. RESULTS: Sixty-eight fluid challenge were administered in 49 patients. At the time of fluid challenge, almost all were mechanically ventilated (99%), with 85% receiving norepinephrine. Admission diagnosis was septic shock in 70% of patients. Patients had a Sequential Organ Failure Assessment score of 10 [7 to 12] and a median Simplified Acute Physiology Score II of 61 [49 to 69]. Relative ΔCO bias was 7.8° (6.3°) with radial limits of agreement of ±41.7°, polar concordance rate 80% and clinical concordance rate 74%. ΔCO bias was associated with baseline bias (P = 0.007). Baseline bias was associated with radial location of the arterial line (P = 0.03). CONCLUSION: When compared with ODM, PRAM has insufficient performance to track ΔCO induced by fluid challenge in ICU patients. Baseline bias is an independent predictor of trending bias. TRIAL REGISTRATION: IRB 00010254-2016-033.