Assessment of superior vena cava flow and cardiac output in different patterns of patent ductus arteriosus shunt

Inter-observer variability of right ventricular output measurement in newborn infants: an observational study

Neonatologist Performed Echocardiography (NPE) is one of the emerging technologies used to evaluate Systemic Blood Flow (SBF) in term and preterm infants. Right Ventricular Output (RVO) can assess SBF correctly in the absence of significant interatrial or interventricular shunts, even in the presence of a large patent ductus arteriosus (PDA), but only few studies evaluated inter-observer variability in neonates. Furthermore, measuring pulmonary peak flow (PF) provides a simple screening tool for low SBF state, easier and faster to perform than RVO; no previous studies evaluated PF inter-observer variability. To describe inter-observer variability of RVO and PF measurement in neonates. We conducted a prospective observational study in term and preterm infants admitted to the Neonatal Intensive Care Unit (NICU). Echocardiographic examinations were performed by two expert neonatologists, blinded to each other. Recordings were analyzed off-line to assess RVO and PF variability between observers. We analyzed a cohort of 33 neonates, 17 of them born prematurely. Inter-observer mean difference for RVO was 22,1 mL/kg/min (p = 0.005); the biggest discrepancy was due to pulmonary valve diameter measurement (p = 0.0001). Inter-observer mean difference for PF measurement was not statistically significant. We found a statistically significant inter-observer variability for RVO measurement, consistent with previous reports; PF instead showed low inter-observer variability. For this reason, PF could be evaluated in future studies as a surrogate for RVO in both term and preterm infants, especially in emergency conditions or in presence of a poor echocardiographic window.

Association between patent ductus arteriosus flow and home oxygen therapy in extremely preterm infants

BACKGROUND

Central blood flow measurements include the estimation of right and left ventricular output (RVO, LVO), superior vena cava (SVC) flow, and calculated patent ductus arteriosus (PDA) flow. We aimed to provide an overview of the maturation patterns of these values and the relationship between PDA flow and the need for home oxygen therapy.

METHODS

This prospective single-center study was conducted in infants born at <26 weeks of gestation. We performed echocardiographic measurements five times during their life (from the 4th post-natal day to the 36th postmenstrual week).

RESULTS

Sixty patients with a mean birth weight of 680 (590, 760) g were included. Postnatal development of LVO and PDA flow peaked at the end of the second postnatal week (427 and 66 mL/kg/min, respectively). The RVO increased between days 4 and 7-8. The SVCF was most stable. The development curves of PDA flow differed between the groups with (n = 28; 47%) and without home oxygen therapy.

CONCLUSION

We present the central blood flow values and their postnatal development in infants <26 weeks of gestation. This study demonstrates the association between PDA flow and the future need for home oxygen therapy.

IMPACT

This study enriches our knowledge of the long-term development of central blood flow parameters and derived patent ductus arteriosus (PDA) flow in extremely preterm infants (<26 weeks). While pulmonary resistance decreased, PDA flow continued to increase from day 4 to the end of the second week of life. Similarly, left ventricular output increased as a marker of preload. The superior vena cava flow remained stable. The observed association between PDA flow and an unfavorable respiratory outcome is important for future studies focusing on the prevention of chronic lung disease.

Early Echocardiographic Predictors of Eventual Need for Patent Ductus Arteriosus Treatment: A Retrospective Study

OBJECTIVE

Hemodynamically significant patent ductus arteriosus (hsPDA) in preterm neonates is associated with end-organ injury including intraventricular hemorrhage. Early treatment may reduce morbidities but may result in overtreatment. This study aimed to examine the association between commonly obtained echocardiographic markers within the first 12 hours of life and eventual treatment of an hsPDA.

STUDY DESIGN

Patients with <32 weeks' gestational age had blinded echocardiograms done within the first 12 hours of life as part of research protocols. Subsequent treatment of the patent ductus arteriosus (PDA) was determined by the clinical team independent of echocardiogram results. t-tests and chi-square tests were done for continuous data and categorical outcomes. A receiver operating curve was created to optimize cutoff values.

RESULTS

 Among 199 neonates studied (mean time of echocardiogram 6.7 h after birth), those needing PDA treatment had higher left ventricular output (LVO), right ventricular output (RVO), and superior vena cava (SVC) flow (p-values 0.007, 0.044, and 0.012, respectively). Cutoffs for predicting PDA treatment were LVO > 204 mL/kg/min (63% sensitivity, 66% specificity), RVO > 221 mL/kg/min or SVC flow > 99 mL/kg/min (sensitivities 70 and 43%, specificities 48 and 73%, respectively).

CONCLUSION

 Preterm neonates with higher markers of cardiac output in the first 12 hours of birth later required PDA treatment. These data are the first to use standard cardiac output measures in the first 12 hours of life to predict the need for future PDA treatment. Further prospective studies will need to be performed to corroborate these associations between echocardiographic markers and clinical outcomes/morbidities.

KEY POINTS

· Early diagnosis of hsPDA may prevent severe morbidity and death.. · There are echocardiographic markers beyond duct size and flow direction that may aid early diagnosis.. · Cardiac output markers within the first 12 hours of life may predict need for treatment of hsPDA..

Should SVC flow be a routine measure when performing targeted neonatal echocardiography? A narrative review

Superior vena cava is commonly used in neonatal hemodynamics and is suggested to be the best available non-invasive marker for systemic circulation in preterm infants. Inter- and intra-observer variability remain to be an issue. Its association with neonatal outcomes is has not been established. This is a narrative review about this marker, its use, and its potential pitfalls.

OBJECTIVE

This is a narrative review about SVC flow in preterm infants, physiology, techniques of measurement and its potential association with outcomes.

SOURCES

Literature revie mainly PubMED.

SUMMARY OF THE FINDINGS

SVC flow measurement has some limitations and pitfalls.

CONCLUSIONS

SVC flow association with neonatal outcomes, still needs to be established in further research.

Echocardiographic Quantification of Superior Vena Cava (SVC) Flow in Neonates: Pilot Study of Modified Technique

Ultrasound Superior Vena Cava (SVC) flow assessment is a common measure of systemic and cerebral perfusion, although accuracy is limited. The aim of this study was to evaluate whether any improvements in accuracy could be achieved by measuring stroke distance from the instantaneous mean velocity, rather than from peak velocity, and by directly tracing area from images obtained with a high frequency linear probe. Paired phase contrast magnetic resonance imaging (PCMRI) and ultrasound assessments of SVC flow were performed in a pilot cohort of 7 infants. Median postnatal age, corrected gestation and weight at scan were 7 (2–74) days, 34.8 (31.7–37.2) weeks 1870 (970–2660) g. Median interval between PCMRI and ultrasound scans was 0.3 (0.2–0.5) h. The methodology trialed here showed a better agreement with PCMRI (mean bias −8 mL/kg/min, LOA −25–+8 mL/kg/min), compared to both the original method reported by Kluckow et al. (mean bias + 42 mL/kg/min, LOA −53–+137 mL/kg/min), and our own prior adaptation (mean bias + 23 mL/kg/min, LOA −25–+71 mL/kg/min). Ultrasound assessment of SVC flow volume using the modifications described led to enhanced accuracy and decreased variability compared to prior techniques in a small cohort of premature infants.

Intraventricular hemorrhage prediction in premature neonates in the era of hemodynamics monitoring: a prospective cohort study

Unstable hemodynamics and prematurity are the main players in intraventricular hemorrhage (IVH) development. Our objective was to study 8 the use of superior vena cava flow (SVCF), left ventricular output (LVO), and right ventricular output (RVO), and anterior cerebral artery (ACA) Doppler measures in prediction of IVH in the first week of life in preterm infant ≤ 32 weeks and birth weight ≤ 1500 g. This prospective cohort study was conducted in 55NICU of Alexandria University maternity hospital. Of 147 enrolled patients, 132 infants born ≤ 32 weeks GA and birth weight ≤ 1500 g were eligible for- the study. One hundred twenty-seven infants completed the study. Infants were scanned for ACA-RI using transfontanellar ultrasound, and SVCF, LVO, and RVO using functional echocardiography in the first 24 h after birth. Patients had another two scans on DOL3 and 7 to detect IVH development. Low SVCF and high ACA-RI significantly increased the risk of IVH using logistic regression models with OR, 3.16; 95%CI, 1.19-8.39; P = 0.02 and OR, 1.64; 95%Cl, 1.10-2.44; P = 0.02, respectively. Low SVCF and high ACA-RI significantly increased risk of catastrophic IVH P = 0.025 and 0.023, respectively. Combined use of low SVCF < 55 ml/kg/min and ACA-RI > 0.75 is predictor of IVH with sensitivity 40.8% and 82.1% specificity.

CONCLUSIONS

There are strong relations between both low SVCF and high ACA-RI, and IVH development in premature neonates ≤ 32 weeks and birth weight ≤ 1500 g, with more significance towards catastrophic IVH. Admission RSS and LVO are the strongest factors affecting SVCF. Maternal anemia, patent ductus arteriosus size (mm/kg), and capillary refill time were significantly associated with high ACA-RI. These findings help in more understanding of pathophysiological factors affecting central perfusion that might affect the longer term neurodeveopmental outcome.

TRIAL REGISTRATION

This work was registered in clinical trial.gv no NCT05050032.

WHAT IS KNOWN

•Whether SVCF and RI-ACA can predict IVH in preterm neonates is still debatable.

WHAT IS NEW

•Low SVC flow and high ACA-RI significantly increased risk of IVH, confirming the role of hypoperfusion-reperfusion cycle in IVH development. The most striking result that combined metrics using the cut-off value of < 41 ml/kg/min for SVCF and > 0.85 for ACA-RI "in the first day of life" can correctly reject the presence of IVH in 98% of patients "during the first week of life."

Fatal accidental lipid overdose with intravenous composite lipid emulsion in a premature newborn: a case report

Background

Tenfold or more overdose of a drug or preparation is a dreadful adverse event in neonatology, often due to an error in programming the infusion pump flow rate. Lipid overdose is exceptional in this context and has never been reported during the administration of a composite intravenous lipid emulsion (ILE).

Case presentation

Twenty-four hours after birth, a 30 weeks’ gestation infant with a birthweight of 930 g inadvertently received 28 ml of a composite ILE over 4 h. The ILE contained 50% medium-chain triglycerides and 50% soybean oil, corresponding to 6 g/kg of lipids (25 mg/kg/min). The patient developed acute respiratory distress with echocardiographic markers of pulmonary hypertension and was treated with inhaled nitric oxide and high-frequency oscillatory ventilation. Serum triglyceride level peaked at 51.4 g/L, 17 h after the lipid overload. Triple-volume exchange transfusion was performed twice, decreasing the triglyceride concentration to < 10 g/L. The infant’s condition remained critical, with persistent bleeding and shock despite supportive treatment and peritoneal dialysis. Death occurred 69 h after the overdose in a context of refractory lactic acidosis.

Conclusions

Massive ILE overdose is life-threatening in the early neonatal period, particularly in premature and hypotrophic infants. This case highlights the vigilance required when ILEs are administered separately from other parenteral intakes. Exchange transfusion should be considered at the first signs of clinical or biological worsening to avoid progression to multiple organ failure.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12887-021-03064-6.