Yasser N. Elsayed

The impact of integrated evaluation of hemodynamics using targeted neonatal echocardiography with indices of tissue oxygenation: a new approach

Objective:To study the impact of integrated evaluation of hemodynamics (IEH) using targeted neonatal echocardiography, together with regional tissue oxygenation, fractional oxygen extraction using near-infrared spectroscopy on the management of infants with compromised hemodynamics.Study Design:Retrospective cohort comparison of two groups of infants with compromised hemodynamics. EPOCH 1: did not undergo IEH (January 2012 to March 2014); EPOCH 2: underwent IEH (April 2014 to December 2015). The primary outcome was the time to recovery.Results:In all, 340 infants were included; 158 underwent IEH with a median (IQR) of 2 (1 to 3) evaluations per infant. Reasons for assessment included PDA (60%), compromised systemic circulation (14%) and clinically suspected pulmonary hypertension (22%). The time to recovery was shorter in IEH group in patients with compromised systemic circulation median (IQR), 32 h (24 to 63) compared with none IEH group 71 h (36 to 96), pulmonary hypertension 63 h (14.2 to 102) in IEH group compared with 68 h (24 to 240) in none IEH group, there were fewer PDA-related complications in preterm infants with PDA in IEH group.Conclusion:IEH was associated with shorter time to clinical recovery in infants with compromised hemodynamics

The Impact of Integrated Evaluation of Hemodynamics on Management of Preterm Infants with Late-Onset Compromised Systemic Circulation

Objectives To study the impact of integrated evaluation of hemodynamics (IEH), using targeted neonatal echocardiography (TNE), cerebral regional tissue oxygenation (crRTO), and fractional oxygen extraction (FOE), using near‐infrared spectroscopy (NIRS) on the management of infants with late‐onset compromised systemic circulation (LCSC), and evaluation of the hemodynamic characteristics. Study Design Retrospective cohort study comparing infants with LCSC who underwent IEH (April 2014 to May 2016) with an earlier EPOCH who did not undergo IEH (January 2012 to March 2014). The primary outcome was the time to recovery. Results Total 43 infants were included; 18 infants underwent IEH with a median (IQR) 2 (1‐3) assessments per infant. The time to recovery was shorter in IEH group with a median (IQR) 28 hours (15‐62) compared with non‐IEH group 96 hours (30‐160). Autoregulation was compromised in 50%, and systemic vascular resistance (SVR) was low in 67%. Conclusion IEH was associated with shorter time to recovery in infants with LCSC.

Integrated evaluation of hemodynamics: a novel approach for the assessment and management of preterm infants with compromised systemic circulation

ObjectiveTo establish normal reference values for tissue oxygen delivery and consumption in preterm infants and demonstrate the usefulness of the integrated evaluation of hemodynamics (IEH) in preterm infants with compromised systemic circulation (CSC).MethodsThis study included 32 stable preterm infants and 6 infants (selected cases) who underwent IEH. IEH is a multimodal approach which integrates clinical parameters: data obtained from near-infrared spectroscopy (NIRS) and targeted neonatal echocardiography (TNE).ResultsThirty-two hemodynamically stable preterm infants underwent 57 IEH studies. The mean (10th and 90th percentiles) were 0.23 (0.14 and 0.29) for cerebral fractional oxygen extraction (crFOE), 0.2 (0.13 and 0.24) for renal fractional oxygen extraction (rnFOE), and 0.22 (0.19 and 0.27) for mesenteric fractional oxygen extraction (msFOE). The time to full clinical recovery in all sick infants after the change of management was between 4 and 48 h.ConclusionIEH was useful in targeting the management of preterm infants with CSC.

Serial serum brain-type natriuretic peptide (BNP) identifies compromised blood flow in infants with hemodynamically significant patent ductus arteriosus

Background: The physiological correlates of elevated serum brain-type natriuretic peptide (BNP) in hemodynamically significant patent ductus arteriosus (HSPDA) are unclear. Objective: To determine if serial BNP measured at 48-72 hours of age, before and after non-steroidal anti-inflammatory drugs (NSAID) treatment of HSPDA reflect compromised blood flow indices, in infants < 31 weeks of gestational age (GA). Design/methods: In a prospective blinded study, 70 infants < 31 weeks GA, admitted to Winnipeg NICUs from August 2010 to September 2011, had serum BNPs and echocardiograms at 48-72 hours of age, before and after medical treatment of HSPDA. All BNP and logarithm of BNP (logBNP) were correlated by linear regression with contemporaneous blood flow indices for: 1) systemic hemodynamic indices (corrected left and right ventricular outputs [LVO, RVO], RVO/LVO ratio, superior vena cava flow [SVCF], SVCF/LVO); 2) regional blood flow indices (middle cerebral artery flow [MCAF], MCAF/LVO ratio, middle cerebral artery resistive index [MCARI], middle cerebral artery pulsatility index [MCAPI]; celiac artery flow [CAF], CAF/LVO ratio, celiac artery resistive index [CARI], and celiac artery pulsatility index [CAPI]). Results: Twenty-six of 70 infants developed HSPDA at 6 ± 2 days. Both BNP and logBNP had similar correlations with all indices, but logBNP showed better goodness of fit. The best correlation was at 48-72 hours of life. Analyzing systemic hemodynamics, logBNP best correlated with SVCF (β -0.49, R 2 0.24, p < 0.0001), SVCF/LVO (β -0.55, R 2 0.31, p < 0.0001), RVO/LVO (β -0.59, R 2 0.35, p < 0.0001), LVO (β 0.4, R 2 0.16, p < 0.0001), and RVO (β -0.35, R 2 0.12, p < 0.0001). For regional blood flow, logBNP best correlated with MCARI (β 0.6, R 2 0.35, p < 0.0001), MCAPI (β 0.5, R 2 0.29, p < 0.001), and MCAF (β -0.34, R 2 0.12, p < 0.0001). Conclusions: BNP correlates with blood flow indices in preterm infants with HSPDA mainly at 48-72 hours reflecting the value of pre-symptomatic physiologic prediction by BNP.

Cardiac Air Embolism in Neonates: A Hemodynamic Perspective

Cardiac air embolism should be suspected in any neonate with acute unexplained cardiovascular collapse or worsening oxygenation. We present here five cases that presented with the above symptoms. A comprehensive evaluation including targeted neonatal echocardiography and near-infrared spectroscopy helped confirm the diagnosis and assess the hemodynamic state. Management was supportive including left lateral positioning, chest compressions, and cardiovascular medications to treat pulmonary hypertension and systemic hypotension.

The impact of different modes of noninvasive ventilation on hemodynamics and regional cerebral and splanchnic oximetry in the premature newborn

Objective: The objective of this study was to compare the effects of triggered pressure assist (TrPA) to nasal continuous positive airway pressure (nCPAP) on cerebral and splanchnic regional blood flow and tissue oxygenation. Methods: Stable preterm neonates (<32 weeks gestation) receiving nCPAP had echocardiographic determination of hemodynamics and cerebral and splanchnic regional tissue oxygenation monitoring using near-infrared spectroscopy before and 3 h after switching to TrPA. Results: Ten neonates (birth weight; 1120 ± 450 g, gestation; 27.6 ± 1.5 weeks) were studied at 13.3 ± 12.4 days (mean ± standard deviation). The end-expiratory pressure was 5 ± 1 cm H 2 O in both modes. There were no significant differences in any of the hemodynamic measurements between nCPAP and TrPA. Cerebral regional tissue oxygen saturation (CrSO 2 ; 74.5 ± 6.9 vs. 73.1 ± 5.8; P < 0.001) and splanchnic rSO 2 (72.4 ± 10.4 vs. 68.0 ± 10.8; P < 0.001) were greater during TrPA compared to nCPAP. In addition, the splanchnic/CrSO 2 ratio was higher on TrPA (0.97 ± 0.15 vs. 0.92 ± 0.15; P < 0.001). The measurements of splanchnic and CrSO 2 were not affected by feedings. Conclusions: Switching from nCPAP to TrPA did not result in significant changes in cardiac output or hemodynamics when the end-expiratory pressure was held constant. TrPA was associated with a small increase in CrSO 2 and a larger increase in splanchnic rSO 2 . These changes were independent of feeding. The clinical significance of these small magnitude changes is uncertain.

Pre-symptomatic prediction of morbitidies in preterm infants with patent ductus arteriosus by targeted neonatal echocardiography and brain-type natriuretic peptide

Objectives: Our objective was to compare patent ductus arteriosus (PDA) diameter, PDA score and brain-type natriuretic peptide (BNP) measurements at 48-72 hours of life, for prediction of neonatal morbidities. We hypothesized that use of a PDA score with BNP, may improve pre-symptomatic prediction of PDAs associated with adverse outcomes. Method: Infants < 31 weeks GA were prospectively studied by targeted neonatal echocardiogram (TNE) at 48-72 hours age, composite PDA score and serum BNP assay; the clinical team remained blinded. PDA was independently diagnosed by echocardiography at time of clinical suspicion (6 ± 2 days), and treated at discretion of the clinical team. Primary outcome was survival with one or more of adverse outcomes (intraventricular hemorrhage [IVH], bronchopulmonary dysplasia [BPD], retinopathy of prematurity [ROP], necrotizing enterocolitis [NEC]). Results: A PDA was present in 56 of 70 infants studied at 48-72 hours; 30 were eventually diagnosed with PDA but never required treatment, 19 required medical treatment, 7 surgical ligation. After adjustment for gestation, PDA diameter did not predict any adverse outcome, PDA score was associated with increased risk of any adverse outcome and high BNP was associated with IVH, BPD, or survival with any adverse outcome. Conclusions: Comprehensive PDA evaluation at 48-72 hours of age may predict the subsequent occurrence of adverse outcomes and may be useful to define the PDA treatment threshold.