Bioreactance-derived haemodynamic parameters in the transitional phase in preterm neonates: a longitudinal study

Bioreactance assessment of cardiac output lacks reliability for the follow-up of patients with pulmonary hypertension

Cardiac output (CO) is one of the primary prognostic factors evaluated during the follow-up of patients treated for pulmonary hypertension (PH). It is recommended that it be measured using the thermodilution technique during right heart catheterization. The difficulty to perform iterative invasive measurements on the same individual led us to consider a non-invasive option. The aims of the present study were to assess the agreement between CO values obtained using bioreactance (Starling™ SV) and thermodilution, and to evaluate the ability of the bioreactance monitor to detect patients whose CO decreased by more than 15% during follow-up and, accordingly, its usefulness for patient monitoring. A prospective cohort study evaluating the performance of the Starling™ SV monitor was conducted in patients with clinically stable PH. Sixty patients referred for hemodynamic assessment were included. CO was measured using both the thermodilution technique and bioreactance during two follow-up visits. A total of 60 PH patients were included. All datasets were available at the baseline visit (V0) and 50 of them were usable during the follow-up visit (V1). Median [IQR] CO was 4.20 l/min [3.60-4.70] when assessed by bioreactance, and 5.30 l/min [4.57-6.20] by thermodilution (p<0.001). The Spearman correlation coefficient was 0.51 [0.36-0.64], and the average deviation on Bland-Altman plot was -1.25 l/min (95% CI [-1.48-1.01], p<0.001). The ability of the monitor to detect a variation in CO of more than 15% between two follow-up measurements, when such variation existed using thermodilution, was insufficient for clinical practice (AUC = 0.54, 95% CI [0.33-0.75]).

Electrical Cardiometry during transition and short-term outcome in very preterm infants: a prospective observational study

The purpose of this study is to evaluate the association of Electrical Cardiometry (EC)-derived cardiac output indexed to weight (CO) and its changes during the first 48 h in relation to adverse short-term outcome in very preterm infants. In this prospective observational study of preterm infants < 32 weeks gestational age (GA), the combined adverse outcome was defined as mortality or abnormal cranial ultrasound (any grade intracranial hemorrhage (ICH) or periventricular leukomalacia) within the first 2 weeks postnatally. Logistic regression models were used to investigate the association between median CO and outcome and mixed-effects models for the time trajectory of CO. In the absence of device-specific thresholds for low or high CO, no thresholds were used in our analysis. Fifty-three infants (median (IQR) GA 29.0 (25.4-30.6) weeks, birthweight 1020 (745-1505) g) were included in the analysis. Median CO was 241 (197-275) mL/kg/min for the adverse outcome and 198 (175-227) mL/kg/min for normal outcome (odds ratio (OR) (95% confidence interval (95% CI)), 1.01 (1.00 to 1.03); p = 0.028). After adjustment for GA, the difference was not significant (adjusted OR (95% CI), 1.01 (0.99 to 1.02); p = 0.373). CO trajectory did not differ by outcome (p = 0.352). A post hoc analysis revealed an association between CO time trajectory and ICH ≥ grade 2.          Conclusions: EC-derived CO estimates within 48 h postnatally were not independently associated with brain injury (any grade) or mortality in the first 14 days of life. CO time trajectory was found to be associated with ICH ≥ grade 2. What is Known: • Bioreactance-derived cardiac output indexed to bodyweight (CO) in the transitional period has been associated with adverse short-term outcome in preterm infants. What is New: • Electrical Cardiometry (EC)-derived CO measurements in very preterm infants during the transitional period are not independently associated with adverse outcome (death or ultrasound detected brain damage) within 2 weeks postnatally. • In the first 48 h EC-derived CO increases over time and is higher in extremely preterm infants compared to very preterm and differs from previously reported bioreactance-derived CO values.