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Gewählte Publikation:

Baik-Schneditz, N.
Influence of cardiac output on the regional cerebral oxygenation in term neonates during the immediate neonatal transition
Doktoratsstudium der Medizinischen Wissenschaft; Humanmedizin; [ Dissertation ] Graz Medical University; 2019. pp. 84 [OPEN ACCESS]


Autor*innen der Med Uni Graz:
Baik-Schneditz Nariae
Cvirn Gerhard
Freidl Thomas
Pichler Gerhard

Background:The immediate transition from foetus to neonate includes substantial changes especially concerning the cardiovascular system. Furthermore, the brain is one of the most vulnerable organs to hypoxia during this period. The occurrence of brain injury like intraventricular haemorrhage is associated with development of hydrocephalus, poor neurological outcome and even death. Recently, there is a growing interest for advanced monitoring of the cardio-circulatory system and the brain to get further and objective information of neonate’s condition during the immediate postnatal transition after birth. Aim of the study: The aim of this present study was to apply advanced cardio-circulatory and brain monitoring in term neonates and to investigate the potential influence of these cardio-circulatory parameters, especially cardiac output on the cerebral oxygenation. Methods: This is a monocentric, prospective observational study. For non-invasive cardiac output measurements (NICOM) the electrical velocimetry (EV) method was used. Electrocardiogram (ECG) electrodes were placed on the left forehead, left side of the neck, left hemithorax, and left thigh. The pulse oximetry for SpO2 and HR measurements was placed on the right hand or wrist. The cerebral regional oxygen saturation (crSO2)/ cerebral tissue oxygen index (cTOI) were measured using an INVOS cerebral/somatic oximeter monitor with the neonatal sensor/ a NIRO200NX monitor. Monitoring started at minute 1 and was continued until minute 15. At minute 5, 10 and 15 after birth, cardiac output (CO) was calculated as an average out of six 10-second periods (with beat-to-beat analysis). The data of these 10-second periods were only accepted if the signal quality index (SQI) was ≥80%. Immediately, after the end of NICOM and NIRS measurements (15 min after birth), an echocardiography was performed to evaluate the DA and FO. The blood pressure was measured non-invasively at the 15th minute of life using a neonatal cuff of appropriate size at the left upper arm. Mean values of crSO2, cTOI, SpO2 and HR were calculated at minute 5,10 and 15 after birth. The cerebral fractional oxygen extraction (cFTOE) was calculated as (SpO2-crSO2)/SpO2 or as (SpO2-cTOI)/SpO2. Results: During the study period, a total of 185 term neonates were enrolled. crSO2, cTOI and SpO2 parameters showed a statistically significant increase until minute 10 after birth. Accordingly, cFTOE showed a decrease during the observational period. HR decreased towards minute 10, afterwards to minute 15 it increased again. Cardiac output showed a decreasing tendency until minute 10 and stayed stable until minute 15. During the whole observational period, there was no significant correlation between CO and crSO2/cTOI or cFTOE. Conclusion: The present work was the first study to investigate a possible influence between cardiac output and cerebral oxygenation in term infants during the immediate neonatal transition. In our study population, there was no significant correlation between CO and cerebral oxygenation. Male neonates showed tendentially higher cardiac output compared to female neonates. Although, there was no significant correlation between cardiac output and cerebral oxygenation in male and female groups. RS group showed lower cardiac output levels compared to neonates in the non-RS group. This might be due to positive intrathoracic pressure caused by the respiratory support. In term infants there was no significant influence of MABP on cerebral oxygenation, suggesting that there is a well-functioning cerebral autoregulation.

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