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ABSTRACT: BACKGROUND: Perinatal asphyxia influences peripheral oxygenation and perfusion in neonates. OBJECTIVES: The aim was to investigate the influence of perinatal asphyxia on peripheral oxygenation and perfusion in neonates by using near-infrared spectroscopy (NIRS). METHODS: Prospective observational study. Neonates with gestational age >34weeks and birth weight >2000g without infection or congenital malformations were included. Peripheral muscle NIRS measurements in combination with venous occlusion were performed once in the first 48h of life. Tissue oxygenation index (TOI), mixed venous oxygenation (SvO2), fractional oxygen extraction (FOE), haemoglobin flow (Hbflow), oxygen delivery (DO2) and oxygen consumption (VO2) were assessed. Furthermore arterial oxygen saturation, heart rate, blood pressure and temperatures were measured. Neonates with a UapH≤7.15 and an Apgar 5≤6 were compared to neonates with a UapH≥7.15, an Apgar 5≥7 (control group) and a UapH was correlated to NIRS parameters. RESULTS: 8 asphyxiated neonates were compared to 30 neonates in the control group. TOI (67.7±5.5%) and DO2 (29.0±14.2μmol/100mL/min) were significantly lower in asphyxiated neonates compared to the controls (TOI 71.8±4.9%, p=0.045; DO2 43.9±16.9μmol/100mL/min, p=0.028) and FOE was significantly higher (0.33±0.05) compared to the controls (0.28±0.06, p=0.028). Furthermore significant correlations between UapH and DO2 (r=0.78, p=0.022), VO2 (r=0.80, p=0.018) and FOE (r=-0.75, p=0.034) in the asphyxiated group were found. CONCLUSION: Peripheral oxygenation and perfusion measured with NIRS are compromised in neonates with perinatal asphyxia with worsening of parameters and degree of acidosis in the umbilical cord blood.
Early human development 04/2013; · 2.12 Impact Factor
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ABSTRACT: Tilting only the head influences cerebral haemodynamics in term and preterm neonates.
To evaluate near-infrared spectroscopy (NIRS) as a method to detect changes of cerebral oxygenated (HbO(2)) and deoxygenated haemoglobin (Hb) and 'cerebral tissue-oxygenation-index' (cTOI) while tilting. Furthermore to investigate whether the comparison of cTOI and 'cerebral mixed venous oxygen saturation' (tiltSvO(2)), calculated out of the increase of HbO(2) and Hb, improves reproducibility.
During five 'reapplication' periods of NIRS optodes on the left forehead of 40 neonates, five tilting manoeuvres of the head were performed. Changes of NIRS parameters during tilting were analysed. The first quality criterion was defined by a linear increase of total haemoglobin (HbT; r(2) > 0.95). The second quality criterion was: cTOI > tiltSvO(2) (= cTOI - tiltSvO(2)> 0). Analysis of variance components and comparison of mean of standard deviations were applied to data after introduction of each quality criterion.
While HbO(2), Hb and HbT showed a linear increase in all neonates during tilting, cTOI did not change. With the introduction of the second criterion, mean cTOI increased from 73.7 ± 6.9 to 75.1 ± 6.9%, mean tiltSvO(2) decreased from 72.6 ± 7.1 to 65.3 ± 6.9% and mean of standard deviations of both parameters decreased. The analysis of variance components showed no significant change.
A tilting-down manoeuvre of the head of term and preterm neonates can cause an increase of HbO(2), Hb and HbT. tiltSvO(2) can be calculated out of these changes. By introducing two quality criteria, reproducibility of cerebral NIRS measurements (cTOI and tiltSvO(2)) improved.
Neonatology 06/2011; 100(3):253-9. · 2.66 Impact Factor
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ABSTRACT: Comparability and reproducibility of different near-infrared spectroscopy devices measuring regional tissue oxygen saturation remain poor. Aim of the present study was to compare values and reproducibility of cerebral∕peripheral "tissue-oxygenation-index" (TOI; NIRO 300, Hamamatsu(®), Japan) with cerebral∕peripheral "regional-oxygen-saturation" (rSO; INVOS5100, Somanetics(®), USA), and to analyze the influence of quality criteria. Methods: cTOI and crSO2 were measured on the left forehead, pTOI and prSO2 were measured on the left calf. To analyse reproducibility, optodes were reapplied five times. A quality criterion was introduced for cTOI, crSO2 and prSO2. For pTOI quality criteria were introduced in combination with a venous occlusion technique. Results: Cerebral measurements were performed in 37 neonates. cTOI (72.7+∕-6.2%) was lower than crSO2 (83.3+∕-5.8%) (p < 0.001). The mean difference between cTOI and crSO2 was 10%. Mean standard deviations of cTOI and crSO2 were similar (cTOI: 4.9+∕-3.6; crSO2: 4.5+∕-2.6). Peripheral measurements were performed in 39 neonates. pTOI (66.0+∕-7.9%) was lower than prSO2 (82.0+∕-7.0%)(p < 0.001). The mean difference between pTOI and prSO2 was 15%. Mean standard deviations of pTOI (3.7+∕-2.6%) were lower than of prSO2 (5.0+∕-3.0%) (p = 0.047). Conclusion: TOI values were significantly lower than rSO2 values, in cerebral and peripheral measurements. Reproducibility was higher for pTOI than for prSO2.
Journal of Biomedical Optics 05/2011; 16(5):057004. · 3.16 Impact Factor
