Reference Ranges for Arterial Oxygen Saturation, Heart Rate, and Cerebral Oxygen Saturation during Immediate Postnatal Transition in Neonates Born Extremely or Very Preterm.

OBJECTIVE: To define percentile charts for arterial oxygen saturation (SpO2), heart rate (HR), and cerebral oxygen saturation (crSO2) during the first 15 minutes after birth in neonates born very or extremely preterm and with favorable outcome. STUDY DESIGN: We conducted a secondary-outcome analysis of neonates born preterm included in the Cerebral regional tissue Oxygen Saturation to Guide Oxygen Delivery in preterm neonates during immediate transition after birth III (COSGOD III) trial with visible cerebral oximetry measurements and with favorable outcome, defined as survival without cerebral injuries until term age. We excluded infants with inflammatory morbidities within the first week after birth. SpO2 was obtained by pulse oximetry, and electrocardiogram or pulse oximetry were used for measurement of HR. crSO2 was assessed with near-infrared spectroscopy. Measurements were performed during the first 15 minutes after birth. Percentile charts (10th to 90th centile) were defined for each minute. RESULTS: A total of 207 neonates born preterm with a gestational age of 29.7 (23.9-31.9) weeks and a birth weight of 1200 (378-2320) g were eligible for analyses. The 10th percentile of SpO2 at minute 2, 5, 10, and 15 was 32%, 52%, 83%, and 85%, respectively. The 10th percentile of HR at minute 2, 5, 10, and 15 was 70, 109, 126, and 134 beats/min, respectively. The 10th percentile of crSO2 at minute 2, 5, 20, and 15 was 15%, 27%, 59%, and 63%, respectively. CONCLUSIONS: This study provides new centile charts for SpO2, HR, and crSO2 for neonates born extremely or very preterm with favorable outcome. Implementing these centiles in guiding interventions during the stabilization process after birth might help to more accurately target oxygenation during postnatal transition period.

Acid base and metabolic parameters of the umbilical cord blood and cerebral oxygenation immediately after birth.

Objective: Aim was to investigate whether acid-base and metabolic parameters obtained from arterial umbilical cord blood affect cerebral oxygenation after birth in preterm neonates with respiratory support and in term neonates without respiratory support. Study design: This was a post-hoc analysis of secondary outcome parameters of a prospective observational study including preterm neonates with and term neonates without respiratory support. Non-asphyxiated neonates with cerebral oxygenation measured with near-infrared spectroscopy during the first 15 min and with blood gas analyses from arterial umbilical cord blood were included. Arterial oxygen saturation (SpO2) and heart rate (HR) were monitored with pulse oximetry. Potential correlations were investigated between acid-base and metabolic parameters (pH-value, bicarbonate, base-excess, and lactate) and crSO2/cFTOE 5 min after birth. Results: Seventy-seven neonates were included: 14 preterm neonates with respiratory support (mean gestational age [GA] 31.4 ± 4.1 weeks; mean birth weight [BW] 1,690 ± 640 g) and 63 term neonates without respiratory support (GA 38.7 ± 0.8 weeks; BW 3,258 ± 443 g). Mean crSO2 5 min after birth was 44.0% ± 24.2% in preterm and 62.2% ± 20.01% in term neonates. Mean cFTOE 5 min after birth was 0.46 ± 0.06 in preterm and 0.27 ± 0.19 in term neonates. In preterm neonates with respiratory support higher lactate was significantly associated with lower crSO2 and SpO2 and tended to be associated with higher cFTOE. In term neonates without respiratory support no significant correlations were found. Conclusion: In non-asphyxiated preterm neonates with respiratory support, lactate levels were negatively associated with crSO2 and SpO2, whereas in term neonates without respiratory support no associations were observed.

Peripheral muscle fractional tissue oxygen extraction in stable term and preterm neonates during the first 24†h after birth.

Background: Peripheral muscle fractional tissue oxygen extraction (pFTOE) represents the relative extraction of oxygen from the arterial to venous compartment, providing information about dynamic changes of oxygen delivery and oxygen consumption. The aim of the present study was to establish reference values of pFTOE during the first 24 h after birth in stable term and late preterm neonates. Methods: The present study is a post-hoc analysis of secondary outcome parameters of prospective observational studies. Only stable neonates without infection, asphyxia and any medical support were eligible for our analysis to obtain normal values. For measurements of peripheral muscle tissue oxygenation index (pTOI) during the first 24 h after birth in term and preterm neonates, the NIRO200/NIRO200NX was used. Arterial oxygen saturation (SpO2) was obtained by pulse oximetry. pFTOE was calculated out of pTOI and SpO2: pFTOE = (SpO2-pTOI)/SpO2. Measurements of neonates were stratified into four groups according to their respective measurement time point (6 h periods) after birth. Term and preterm neonates were analyzed separately. Mean values of measurements during the first time period (0-6 h after birth) were compared to measurements of the following time periods (second = 7-12 h, third = 13-18 h, fourth = 19-24 h after birth). Results: Two-hundred-fourty neonates (55 term and 185 late preterm neonates) had at least one peripheral muscle NIRS measurements within the first 24 h after birth. Mean gestational age and birth weight were 39.4 ± 1.1 weeks and 3360 (2860-3680)g in term neonates and 34.0 ± 1.4 weeks and 2060 (1750-2350)g in preterm neonates, respectively. In term neonates pFTOE was 0.264 (0.229-0.300), 0.228 (0.192-0.264), 0.237 (0.200-0.274) and 0.220 (0.186-0.254) in the first, second, third and fourth time period. In preterm neonates pFTOE was 0.229 (0.213-0.246), 0.225 (0.209-0.240), 0.226 (0.210-0.242) and 0.238 (0.222-0.255) in the first, second, third and fourth time period. pFTOE did not show any significant changes between the time periods, neither in term nor in preterm neonates. Conclusion: We provide reference values of pFTOE for stable term and late preterm neonates within the first 24 h after birth, which were stable when comparing four 6-h periods. These normal values are of great need for interpreting pFTOE in scientific context as well as for potential future clinical applications.

Cerebral oxygenation immediately after birth and long-term outcome in preterm neonates-a retrospective analysis.

BACKGROUND: Prematurity is associated with increased risk for morbidity and mortality. Aim of this study was to evaluate whether cerebral oxygenation during fetal-to-neonatal transition period was associated with long-term outcome in very preterm neonates. METHODS: Preterm neonates ≤ 32 weeks of gestation and/or ≤ 1500 g with measurements of cerebral regional oxygen saturation (crSO2) and cerebral fractional tissue oxygen extraction (cFTOE) within the first 15 min after birth were analysed retrospectively. Arterial oxygen saturation (SpO2) and heart rate (HR) were measured with pulse oximetry. Long-term outcome was assessed at two years using "Bayley Scales of Infant Development" (BSID-II/III). Included preterm neonates were stratified into two groups: adverse outcome group (BSID-III ≤ 70 or testing not possible due to severe cognitive impairment or mortality) or favorable outcome group (BSID-III > 70). As the association between gestational age and long-term outcome is well known, correction for gestational age might disguise the potential association between crSO2 and neurodevelopmental impairment. Therefore, due to an explorative approach the two groups were compared without correction for gestational age. RESULTS: Forty-two preterm neonates were included: adverse outcome group n = 13; favorable outcome group n = 29. Median(IQR) gestational age and birth weight were 24.8 weeks (24.2-29.8) and 760 g (670-1054) in adverse outcome group and 30.6 weeks (28.1-32.0) (p = 0.009*) and 1250 g (972-1390) (p = 0.001*) in the favorable outcome group, respectively. crSO2 was lower (significant in 10 out of 14 min) and cFTOE higher in adverse outcome group. There were no difference in SpO2, HR and fraction of inspired oxygen (FiO2), except for FiO2 in minute 11, with higher FiO2 in the adverse outcome group. CONCLUSION: Preterm neonates with adverse outcome had beside lower gestational age also a lower crSO2 during immediate fetal-to-neonatal transition when compared to preterm neonates with age appropriate outcome. Lower gestational age in the adverse outcome group would suggest beside lower crSO2 also lower SpO2 and HR in this group, which were however similar in both groups.

Cardiac output and regional-cerebral-oxygen-saturation in preterm neonates during immediate postnatal transition: An observational study.

AIM: To examine potential correlations between cardiac output (CO) with cerebral-regional-oxygen-saturation (crSO2 ) and cerebral-fractional-tissue-oxygen-extraction (cFTOE) during immediate foetal-to-neonatal transition in term and preterm neonates with and without respiratory support. METHODS: Post hoc analyses of secondary outcome parameters of prospective observational studies were performed. We included neonates with cerebral near-infrared-spectroscopy (NIRS) monitoring and an oscillometric blood pressure measurement at minute 15 after birth. Heart rate (HR) and arterial oxygen saturation (SpO2 ) were monitored. CO was calculated with Liljestrand and Zander formula and correlated with crSO2 and cFTOE. RESULTS: Seventy-nine preterm neonates and 207 term neonates with NIRS measurements and calculated CO were included. In 59 preterm neonates (mean gestational age (GA): 29.4 ± 3.7 weeks) with respiratory support, CO correlated significantly positively with crSO2 and significantly negatively with cFTOE. In 20 preterm neonates (GA 34.9 ± 1.3 weeks) without respiratory support and in 207 term neonates with and without respiratory support, CO correlated neither with crSO2 nor with cFTOE. CONCLUSION: In compromised preterm neonates with lower gestational age and in need of respiratory support, CO was associated with crSO2 and cFTOE, whereas in stable preterm neonates with higher gestational age as well as in term neonates with and without respiratory support, no associations were observed.

Correlation between arterial blood pressures and regional cerebral oxygen saturation in preterm neonates during postnatal transition-an observational study.

Objective: To assess whether blood pressure (systolic (SABP), diastolic (DABP), and mean arterial blood pressure (MABP) and cerebral-regional-oxygen-saturation (crSO2) and cerebral-fractional-tissue-oxygen-extraction (cFTOE) are associated after immediate fetal-to-neonatal transition in preterm neonates with and without respiratory support. Study design: Post-hoc analyses of secondary outcome parameters of prospective observational studies were performed. We included moderate and late preterm neonates with and without respiratory support with cerebral NIRS monitoring (INVOS 5100c) and an oscillometric blood pressure measurement at minute 15 after birth. Heart rate (HR) and arterial oxygen saturation (SpO2) were monitored routinely. Blood pressure values were correlated with crSO2 and cFTOE. Results: 47 preterm neonates with NIRS measurements and blood pressure measurement during immediate transition after birth were included. Twenty-five preterm neonates (gestational age: 34.4±1.6 weeks) received respiratory support. In these neonates crSO2 correlated significantly positively with systolic blood pressure (SABP; r = 0.46, p = 0.021), diastolic blood pressure (DABP; r = 0.51, p = 0.009) and, mean arterial pressure (MABP; r = 0.48, p = 0.015). cFTOE correlated significantly negatively with SABP (r = -0.44, p = 0.027), DABP (r = -0.49, p = 0.013) and mean MABP (r = -0.44, p = 0.029). Twenty-two preterm neonates (gestational age: 34.5 ± 1.5 weeks) did not receive respiratory support. In those neonates, neither crSO2 nor cFTOE correlated with blood pressure. Conclusion: In compromised moderate and late preterm neonates with respiratory support, both, crSO2 and cFTOE correlated with blood pressure. These findings suggest that passive pressure-dependent cerebral perfusion was present in preterm neonates with respiratory support, indicating an impaired cerebral autoregulation in those compromised preterm neonates.

Peripheral fractional oxygen extraction measured with near-infrared spectroscopy in neonates-A systematic qualitative review.

Background: Peripheral fractional oxygen extraction (pFOE) measured with near-infrared spectroscopy (NIRS) in combination with venous occlusion is of increasing interest in term and preterm neonates. Objective: The aim was to perform a systematic qualitative review of literature on the clinical use of pFOE in term and preterm neonates and on the changes in pFOE values over time. Methods: A systematic search of PubMed, Embase and Medline was performed using following terms: newborn, infant, neonate, preterm, term, near-infrared spectroscopy, NIRS, oximetry, spectroscopy, tissue, muscle, peripheral, arm, calf, pFOE, OE, oxygen extraction, fractional oxygen extraction, peripheral perfusion and peripheral oxygenation. Additional articles were identified by manual search of cited references. Only studies in human neonates were included. Results: Nineteen studies were identified describing pFOE measured with NIRS in combination with venous occlusion. Nine studies described pFOE measured on the forearm and calf at different time points after birth, both in stable preterm and term neonates without medical/respiratory support or any pathological findings. Nine studies described pFOE measured at different time points in sick preterm and term neonates presenting with signs of infection/inflammation, anemia, arterial hypotension, patent ductus arteriosus, asphyxia or prenatal tobacco exposure. One study described pFOE both, in neonates with and without pathological findings. Conclusion: This systematic review demonstrates that pFOE may provide additional insight into peripheral perfusion and oxygenation, as well as into disturbances of microcirculation caused by centralization in preterm and term neonates with different pathological findings. Systematic review registration: [https://www.crd.york.ac.uk/prospero/], identifier [CRD42021249235].

pFOE or pFTOE as an Early Marker for Impaired Peripheral Microcirculation in Neonates.

BACKGROUND: Peripheral-muscle-fractional-oxygen-extraction (pFOE) and peripheral-muscle-fractional-tissue-oxygen-extraction (pFTOE) are often equated, since both parameters are measured with near-infrared-spectroscopy (NIRS) and estimate oxygen extraction in the tissue. The aim was to investigate the comparability of both parameters and their potential regarding detection of impaired microcirculation. METHODS: Term and preterm neonates with NIRS measurements of upper (UE) and lower extremities (LE) were included. pFOE was calculated out of peripheral-muscle-mixed-venous-saturation (pSvO2), measured with NIRS and venous occlusion, and arterial oxygen saturation (SpO2). pFTOE was calculated out of peripheral-muscle-tissue-oxygen-saturation and SpO2. Both parameters were compared using Wilcoxon-Signed-Rank-test and Bland-Altman plots. RESULTS: 341 NIRS measurements were included. pFOE was significantly higher than pFTOE in both locations. Bland-Altman plots revealed limited comparability, especially with increasing oxygen extraction with higher values of pFOE compared to pFTOE. CONCLUSION: The higher pFOE compared to pFTOE suggests a higher potential of pFOE to detect impaired microcirculation, especially when oxygen extraction is elevated.

The Use of a Disposable Umbilical Clamp to Secure an Umbilical Venous Catheter in Neonatal Emergencies-An Experimental Feasibility Study.

Recent guidelines recommend the umbilical venous catheter (UVC) as the optimal vascular access method during neonatal resuscitation. In emergencies the UVC securement may be challenging and time-consuming. This experimental study was designed to test the feasibility of new concepts for the UVC securement. Umbilical cord remnants were catheterized with peripheral catheters and secured with disposable umbilical clamps. Three different securement techniques were investigated. Secure 1: the disposable umbilical clamp was closed at the level of the inserted catheter. Secure 2: the clamp was closed at the junction of the catheter and plastic wings. Secure 3: the setting of Secure 2 was combined with an umbilical tape. The main outcomes were the feasibility of fluid administration and the maximum force to release the securement. This study shows that inserting peripheral catheters into the umbilical vein and securing them with disposable umbilical clamps is feasible. Rates of lumen obstruction and the effectiveness of the securement were superior with Secure 2 and 3 compared to Secure 1. This new approach may be a rewarding option for umbilical venous catheterization and securement particularly in low-resource settings and for staff with limited experience in neonatal emergencies. However, although promising, these results need to be confirmed in clinical trials before being introduced into clinical practice.

Normal regional tissue oxygen saturation in neonates: a systematic qualitative review.

BACKGROUND: The aim of this systematic qualitative review was to give an overview of reference ranges defined as normal values or centile charts of regional tissue oxygen saturation measured by near-infrared spectroscopy (NIRS) in term and preterm neonates. METHODS: A systematic search of MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials was performed. Additional articles were identified by manual search of cited references. Only human studies in neonates were included. RESULTS: Nineteen studies were identified. Eight described regional tissue oxygen saturation during fetal-to-neonatal transition, six during the first 3 days after birth, four during the first 7 days after birth, and one during the first 8 weeks after birth. Nine described regional tissue oxygen saturation in term, nine in preterm neonates, and one in both. Eight studies published centile charts for cerebral regional tissue oxygen saturation, and only five included large cohorts of infants. Eleven studies described normal values for cerebral, muscle, renal, and abdominal regional tissue oxygen saturation, the majority with small sample sizes. Four studies of good methodological quality were identified describing centile charts of cerebral regional tissue oxygen saturation. CONCLUSIONS: In clinical settings, quality centile charts are available and should be the preferred method when using NIRS monitoring. IMPACT: Near-infrared spectroscopy (NIRS) enables a bed-side non-invasive continuous monitoring of tissue oxygenation. When using NIRS monitoring in a clinical setting, centile charts with good quality are available and should be preferred to normal values. High-quality reference ranges of regional tissue oxygenation in term and preterm born neonates are an important step toward routine clinical application of NIRS.

In Newborn Infants a New Intubation Method May Reduce the Number of Intubation Attempts: A Randomized Pilot Study.

Severe desaturation or bradycardia often occur during neonatal endotracheal intubation. Using continuous gas flow through the endotracheal tube might reduce the incidence of these events. We hypothesized that continuous gas flow through the endotracheal tube during nasotracheal intubation compared to standard nasotracheal intubation will reduce the number of intubation attempts in newborn infants. In a randomized controlled pilot study, neonates were either intubated with continuous gas flow through the endotracheal tube during intubation (intervention group) or no gas flow during intubation (control group). Recruitment was stopped early due to financial and organizational issues. A total of 16 infants and 39 intubation attempts were analyzed. The median (interquartile range) number of intubation attempts and number of abandoned intubations due to desaturation and/or bradycardia were 1 (1-2) and 4 (2-5), (p = 0.056) and n = 3 versus n = 20, (p = 0.060) in the intervention group and control group, respectively. Continuous gas flow through the endotracheal tube during intubation seems to be favorable and there are no major unexpected adverse consequences of attempting this methodology.

BMI and specimen weight: impact on personalized risk profiling for optimized informed consent in breast reduction surgery?

We aimed to evaluate the interaction between individual risk factors and institutional complication rates after reduction mammaplasties to develop a chart for a personalized written patient informed consent. We retrospectively reviewed charts of 804 patients who underwent bilateral breast reduction between 2005 and 2015. The Clavien-Dindo classification was used to classify postoperative complications. Relevant predictors were found by applying a stepwise variable selection procedure. Multilevel predictors were assessed through chi-square tests on the respective deviance reductions. 486 patients were included. The most common complications were wound healing problems (n = 270/56%), foreign body reactions (n = 58/12%), wound infections (n = 45/9, 3%) and fat tissue necrosis (n = 41/8%). The risk factors for the personalized patient chart for the most common complications influencing the preoperative informed consent were: smoking, operative technique, resection weight for wound healing problems; body mass index and allergies for wound infections; and patients' age, resection weight for fat tissue necrosis. The resultant chart of institutionally encountered most common complications based on individual risk factors is a graphical template for obtaining patient informed consent in the future. Whether this approach influences patient information retainment, incidence of filed lawsuits or behavioral change needs to be prospectively tested in future studies.