Cerebral fractional tissue oxygen extraction (cFTOE) during immediate fetal-to-neonatal transition: a systematic qualitative review of the literature.

Cerebral monitoring during immediate fetal-to-neonatal transition is of increasing interest. The cerebral fractional tissue oxygen extraction (cFTOE) is a useful parameter to gain insight in the balance between tissue oxygen delivery and consumption during this complex process. The aim of this study was to review the literature on cFTOE during the first 15 min immediately after birth. A systematic qualitative literature research was last performed on 23 November 2023 of PubMed and EMBASE with the following search terms: neonate, infant, newborn, transition, after birth, delivery room, NIRS, near-infrared spectroscopy, spectroscopy, cFTOE, cerebral fractional tissue oxygenation extraction, cerebral oxygenation, and fractional oxygen extraction. Additional published reports were identified through a manual search of references in retrieved articles and in review articles. The methodological quality of the included studies was assessed by predefined quality criteria. Only human studies with data of cFTOE in the first 15 min after birth were included. Accordingly, exclusion criteria were defined as no measurement of cFTOE or no measurement within the first 15 min after birth. Across all studies, a total of 3566 infants (2423 term, 1143 preterm infants) were analysed. Twenty-five studies were identified describing cFTOE within the first 15 min after birth. Four studies established reference ranges for cFTOE and another four studies focused on the effect of pre-/perinatal circumstances on cFTOE in the first 15 min after birth. Six studies investigated the course of cFTOE after transition in infants without complications. Eleven studies analysed different potentially influencing parameters on cFTOE during transition. CONCLUSION: This systematic review provides a comprehensive insight on cFTOE during uncomplicated transition as well as the influence of perinatal circumstances, respiratory, haemodynamic, neurological, and laboratory parameters in preterm and term infants. WHAT IS KNOWN: • The NIRS-measured cerebral fractional tissue oxygen extraction (cFTOE) is a useful parameter to estimate the balance between oxygen delivery and consumption. • During normal transition, the cFTOE decreases in the first minutes after birth and then remains at a stable plateau. WHAT IS NEW: • The cFTOE is a promising parameter that gives additional information on cerebral oxygenation and perfusion in preterm and term infants. • Several hemodynamic, metabolic, respiratory, and perinatal factors are identified, influencing the oxygen extraction of the newborn's brain after birth.

Cardiac output calculation using the Liljestrand and Zander formula: is this method applicable during immediate transition after birth? - A post hoc analysis.

The transition from intrauterine to extrauterine life is a critical period for neonates. Assessing the cardiovascular transition during this period immediately after birth is crucial but challenging. The present study compares adjusted estimated cardiac output values calculated by the Liljestrand and Zander formula (COest/adj LaZ) with non-invasively measured cardiac output values (CO-bioimpedance) during immediate transition after birth. We performed a secondary outcome analysis of a prospective observational study in preterm and term neonates. Ten and 15 min after birth, arterial blood pressure and heart rate were assessed, and CO-bioimpedance was measured using electrical bioimpedance method (Aesculon monitor, Osypka, Germany). We calculated COest/adj LaZ and compared it to CO-bioimpedance. Further, we performed a correlation analysis. Thirty-two neonates with a median (IQR) gestational age of 37.0 (32.0-39.4) weeks were included. Mean ± SD CO-bioimpedance was 0.62 ± 0.15 l/min, and COest/adj LaZ was calculated to be 0.64 ± 0.10 l/min, whereby both correlated significantly (p = 0.025, r = 0.359) with each other.  Conclusion: The present study demonstrates high comparability of COest/adj LaZ and CO-bioimpedance in neonates during immediate transition after birth, suggesting that cardiac output can be derived in a cost-effective and feasible manner if other methods are not available. What is Known: • Echocardiography is considered the gold standard for non-invasive CO evaluation, but its feasibility during the immediate transition period is limited. What is New: • Non-invasive methods such as CO-bioimpedance for cardiac output (CO) measurement and the Liljestrand and Zander (LaZ) formula for estimating CO offer promising alternatives during the immediate transition period.

Chest compression rates of 60/min versus 90/min during neonatal cardiopulmonary resuscitation: a randomized controlled animal trial.

Background: To compare chest compression (CC) rates of 60/min with 90/min and their effect on the time to return of spontaneous circulation (ROSC), survival, hemodynamic, and respiratory parameters. We hypothesized that asphyxiated newborn piglets that received CC at 60/min vs. 90/min during cardiopulmonary resuscitation would have a shorter time to ROSC. Methods: Newborn piglets (n = 7/group) were anesthetized, tracheotomized and intubated, instrumented and exposed to 45 min normocapnic hypoxia followed by asphyxia and cardiac arrest. Piglets were randomly allocated to a CC rate of 60/min or 90/min. CC was performed using an automated CC machine using CC superimposed with sustained inflation. Hemodynamic parameters, respiratory parameters, and applied compression force were continuously measured. Results: The mean (IQR) time to ROSC was 97 (65-149) s and 136 (88-395) s for CC rates of 60/min and 90/min, respectively (p = 0.31). The number of piglets that achieved ROSC was 5 (71%) and 5 (71%) with 60/min and 90/min CC rates, respectively (p = 1.00). Hemodynamic parameters (i.e., diastolic and mean blood pressure, carotid blood flow, stroke volume, end-diastolic volume, left ventricular contractile function) and respiratory parameters (i.e., minute ventilation, peak inflation and peak expiration flow) were all similar with a CC rate of 60/min compared to 90/min. Conclusion: Time to ROSC, hemodynamic, and respiratory parameters were not significantly different between CC rates of 60/min vs. 90/min. Different CC rates during neonatal resuscitation warrant further investigation.

Four Different Finger Positions and Their Effects on Hemodynamic Changes during Chest Compression in Asphyxiated Neonatal Piglets.

Background: The Neonatal Life Support Consensus on Science With Treatment Recommendations states that chest compressions (CC) be performed preferably with the 2-thumb encircling technique. The aim of this study was to compare the hemodynamic effects of four different finger positions during CC in a piglet model of neonatal asphyxia. Methods: Seven asphyxiated post-transitional piglets were randomized to CC with 2-thumb-, 2-finger-, knocking-fingers-, and over-the-head 2-thumb-techniques for one minute at each technique. CC superimposed with sustained inflations were performed manually. Results: Seven newborn piglets (age 0-4 days, weight 2.0-2.1 kg) were included in the study. The mean (SD) slope rise of carotid blood flow was significantly higher with the 2-thumb-technique and over-the-head 2-thumb-technique (118 (45) mL/min/s and 121 (46) mL/min/s, respectively) compared to the 2-finger-technique and knocking-finger-technique (75 (48) mL/min/s and 71 (67) mL/min/s, respectively) (p < 0.001). The mean (SD) dp/dtmin (as an expression of left ventricular function) was significantly lower with the 2-thumb-technique, with -1052 (369) mmHg/s, compared to -568 (229) mmHg/s and -578(180) mmHg/s (both p = 0.012) with the 2-finger-technique and knocking-finger-technique, respectively. Conclusion: The 2-thumb-technique and the over-the-head 2-thumb-technique resulted in improved slope rises of carotid blood flow and dp/dtmin during chest compression.

Haemodynamic changes with varying chest compression rates in asphyxiated piglets.

BACKGROUND: Current neonatal resuscitation guidelines recommend that chest compressions (CCs) be delivered at a rate of 90/min. The aim of the study was to investigate the haemodynamic effects of different CC rates in a neonatal piglet model. METHODS: Six asphyxiated piglets were randomised to CC with rates of 60/min, 90/min, 120/min, 150/min and 180/min for 1 min at each rate. CCs superimposed with sustained inflations were performed with an automated CC machine. RESULTS: Six newborn piglets (age 0-3 days, weight 2.0-2.3 kg) were included in the study. Overall, there was a gradual increase in stroke volume, minimum and maximum rate of left ventricle pressure change (dp/dtmin and dp/dtmax), and carotid blood flow until CC rate of 150/min, with a level-off effect at a CC rate of 180/min. However, cardiac output continued to increase with the highest being at a CC rate of 180/min. CONCLUSION: Rate of CC was associated with changes in haemodynamic parameters during cardiopulmonary resuscitation. CC rate of 150-180/min during CC resulted in the highest cardiac output and arterial blood pressure. TRIAL REGISTRATION NUMBER: Preclincialtrials.eu PCTE0000249.

Chest compressions in newborn infants: a scoping review.

AIM: The International Liaison Committee on Resuscitation Neonatal Life Support Task Force undertook a scoping review of the literature to identify evidence relating to neonatal cardiopulmonary resuscitation. METHODS: MEDLINE complete, EMBASE and Cochrane database of Systematic reviews were searched from inception to November 2021. Two authors screened titles and abstracts and full text reviewed. Studies were eligible for inclusion if they were peer-reviewed and assessed one of five aspects of chest compression in the newborn infant including: (1) heart rate thresholds to start chest compressions (CC), (2) compression to ventilation ratio (C:V ratio), (3) CC technique, (4) oxygen use during CC and 5) feedback devices to optimise CC. RESULTS: Seventy-four studies were included (n=46 simulation, n=24 animal and n=4 clinical studies); 22/74 were related to compression to ventilation ratios, 29/74 examined optimal technique to perform CC, 7/74 examined oxygen delivery and 15/74 described feedback devices during neonatal CC. CONCLUSION: There were very few clinical studies and mostly manikin and animal studies. The findings either reinforced or were insufficient to change previous recommendations which included to start CC if heart rate remains <60/min despite adequate ventilation, using a 3:1 C:V ratio, the two-thumb encircling technique and 100% oxygen during CC.

Chest Compression Rates of 90/min versus 180/min during Neonatal Cardiopulmonary Resuscitation: A Randomized Controlled Animal Trial.

BACKGROUND: To compare chest compression (CC) rates of 90/min with 180/min and their effect on the time to return of spontaneous circulation (ROSC), survival, hemodynamic, and respiratory parameters. We hypothesized that asphyxiated newborn piglets that received CC at 180/min vs. 90/min during cardiopulmonary resuscitation would have a shorter time to ROSC. METHODS: Newborn piglets (n = 7/group) were anesthetized, intubated, instrumented and exposed to 45 min normocapnic hypoxia followed by asphyxia and cardiac arrest. Piglets were randomly allocated to a CC rate of 180/min or 90/min. CC was performed using an automated chest compression machine using CC superimposed with sustained inflation. Hemodynamic and respiratory parameters and applied compression force were continuously measured. RESULTS: The mean (SD) time to ROSC was 91 (34) and 256 (97) s for CC rates of 180/min and 90/min, respectively (p = 0.08). The number of piglets that achieved ROSC was 7 (100%) and 5 (71%) with 180/min and 90/min CC rates, respectively (p = 0.46). Hemodynamic parameters (i.e., diastolic and mean blood pressure, carotid blood flow, stroke volume, end-diastolic volume, left ventricular contractile function) and respiratory parameters (i.e., minute ventilation, peak inflation and peak expiration flow) were all improved with a CC rate of 180/min. CONCLUSION: Time to ROSC and hemodynamic and respiratory parameters were not statistical significant different between CC rates of 90/min and 180/min. Higher CC rates during neonatal resuscitation warrant further investigation.

Chest compressions and medications during neonatal resuscitation.

Prolonged resuscitation in neonates, although quite rare, may occur in response to profound intractable bradycardia as a result of asphyxia. In these instances, chest compressions and medications may be necessary to facilitate return of spontaneous circulation. While performing chest compressions, the two thumb method is preferred over the two finger technique, although several newer approaches are under investigation. While the ideal compression to ventilation ratio is still uncertain, a 3:1 ratio remains the recommendation by the Neonatal Resuscitation Program. Use of feedback mechanisms to optimize neonatal cardiopulmonary resuscitation (CPR) show promise and are currently under investigation. While performing optimal cardiac compressions to pump blood, use of medications to restore spontaneous circulation will likely be necessary. Current recommendations are that epinephrine, an endogenous catecholamine be used preferably intravenously or by intraosseous route, with the dose repeated every 3-5 minutes until return of spontaneous circulation. Finally, while the need for volume replacement is rare, it may be considered in instances of acute blood loss or poor response to resuscitation.

Acid base and blood gas analysis in term neonates immediately after birth with uncomplicated neonatal transition.

BACKGROUND: Acid base and blood gas measurements provide essential information, especially in critically ill neonates. After birth, rapidly changing physiology and difficulty to obtain blood samples represent unique challenges. OBJECTIVES: The aim of the present study was to establish normal values of capillary acid base and blood gas analysis immediately after birth in term neonates after uncomplicated neonatal transition. METHOD: This is a post-hoc-analysis of ancillary outcome parameter of a prospective observational study in term neonates immediately after caesarean section. Neonates were included after immediate neonatal transition without need of medical support and a capillary blood sample was taken by a heel-stick within 15-20 minutes after birth. RESULT: One hundred thirty-two term neonates were included with mean (SD) gestational age of 38.7 ± 0.7 weeks. The blood was drawn mean (SD) 16 ± 1.7 minutes after birth. The mean (SD) values of the analyses were: pH 7.30 ± 0.04, pCO2 52.6 ± 6.4, base excess - 0.9 ± 1.7 and bicarbonate 24.8 ± 1.6. CONCLUSION: This is the first study describing acid base and blood gas analyses in term neonates immediately after birth with uncomplicated neonatal transition.

Assessment of optimal chest compression depth during neonatal cardiopulmonary resuscitation: a randomised controlled animal trial.

AIM: The study aimed to examine the optimal anterior-posterior depth which will reduce the time to return of spontaneous circulation and improve survival during chest compressions. Asphyxiated neonatal piglets receiving chest compression resuscitated with a 40% anterior-posterior chest depth compared with 33%, 25% or 12.5% will have reduced time to return of spontaneous circulation and improved survival. METHODS: Newborn piglets (n=8 per group) were anaesthetised, intubated, instrumented and exposed to 45 min normocapnic hypoxia followed by asphyxia and cardiac arrest. Piglets were randomly allocated to four intervention groups ('anterior-posterior 12.5% depth', 'anterior-posterior 25% depth', 'anterior-posterior 33% depth' or 'anterior-posterior 40% depth'). Chest compressions were performed using an automated chest compression machine with a rate of 90 per minute. Haemodynamic and respiratory parameters, applied compression force, and chest compression depth were continuously measured. RESULTS: The median (IQR) time to return of spontaneous circulation was 600 (600-600) s, 135 (90-589) s, 85 (71-158)* s and 116 (63-173)* s for the 12.5%, 25%, 33% and 40% depth groups, respectively (*p<0.001 vs 12.5%). The number of piglets that achieved return of spontaneous circulation was 0 (0%), 6 (75%), 7 (88%) and 7 (88%) in the 12.5%, 25%, 33% and 40% anterior-posterior depth groups, respectively. Arterial blood pressure, central venous pressure, carotid blood flow, applied compression force, tidal volume and minute ventilation increased with greater anterior-posterior chest depth during chest compression. CONCLUSIONS: Time to return of spontaneous circulation and survival were similar between 25%, 33% and 40% anterior-posterior depths, while 12.5% anterior-posterior depth did not result in return of spontaneous circulation or survival. Haemodynamic and respiratory parameters improved with increasing anterior-posterior depth, suggesting improved organ perfusion and oxygen delivery with 33%-40% anterior-posterior depth. TRIAL REGISTRATION NUMBER: PTCE0000193.

Impact of Carbon Dioxide on Cerebral Oxygenation and Vital Parameters in Stable Preterm and Term Infants Immediately after Birth.

INTRODUCTION: Carbon dioxide (pCO2) induces changes in the tone of cerebral vessels. The aim of the present study was to evaluate the impact of pCO2 on cerebral regional tissue oxygen saturation (crSO2), cerebral fractional tissue oxygen extraction (cFTOE), and cerebral tissue oxygen extraction (cTOE), measured with near-infrared spectroscopy (NIRS), in preterm and term infants 15 min after birth. METHODS: Post hoc analyses of secondary outcome parameters of prospective observational studies were performed. Stable preterm and term infants with cerebral NIRS monitoring (INVOS 5100C) until minute 15 after birth and a blood gas analysis, performed between minutes 14-18 after birth, were included. Heart rate (HR) and arterial oxygen saturation (SpO2) were recorded. pCO2 was correlated with crSO2, cFTOE, cTOE, SpO2, HR, and partial pressure of oxygen (pO2). RESULTS: Eleven preterm infants with a median (IQR) gestational age of 34.8 (32.7-36.1) weeks were analyzed. Mean ± SD pCO2 was 53.5 ± 4.2 mm Hg. At minute 15 after birth, crSO2 was 82.6 (74.3-91.3)%, cFTOE 0.15 ± 0.09, cTOE 14.6 ± 8.4%, SpO2 97.4 ± 2.1%, and HR 152 (136-167) bpm. pCO2 correlated negatively with crSO2 (p = 0.012) and positively with cFTOE (p = 0.035) and cTOE (p = 0.037). Eighty-four term infants with a gestational age of 39.0 (38.5-38.9) weeks were analyzed. pCO2 was 53.5 ± 6.3 mm Hg. At minute 15 after birth, crSO2 was 84.4 (80.8-85.1)%, cFTOE 0.14 ± 0.08, cTOE 13.6 ± 7.9%, SpO2 96.5 ± 2.6%, and HR 155 (153-163) bpm. pCO2 did only negatively correlate with pO2 (p = 0.034) in term infants. CONCLUSION: In preterm infants, higher pCO2 was associated with lower crSO2 and higher cFTOE/cTOE. In term infants, no associations were observed. The present findings suggest that the vasodilatative effect of pCO2 is less pronounced in preterm infants during immediate postnatal transition.

Increased Risk for Cerebral Hypoxia During Immediate Neonatal Transition After Birth in Term Neonates Delivered by Caesarean Section With Prenatal Tobacco Exposure.

Introduction: Maternal tobacco smoking during pregnancy is a global health problem leading to an increased risk for fetal and neonatal morbidities. So far, there are no data of the potential impact of maternal smoking during pregnancy on the most vulnerable period after birth - the immediate postnatal transition. The aim of the present study was therefore, to compare cerebral oxygenation during immediate postnatal transition in term neonates with and without prenatal tobacco exposure. Methods: Included in this post-hoc analysis were healthy term neonates, with measurements of cerebral oxygenation (INVOS 5100C) during the first 15 min after birth, and for whom information on maternal smoking behavior during pregnancy was available. Neonates with prenatal tobacco exposure (smoking group) were matched 1:1 according to gestational age (±1 week), birth weight (±100 grams) and hematocrit (±5 %) to neonates without (non-smoking group). Cerebral regional tissue oxygen saturation (crSO2), cerebral fractional tissue oxygen extraction (cFTOE), arterial oxygen saturation (SpO2) and heart rate (HR) within the first 15 min after birth were compared between the two groups. Results: Twelve neonates in the smoking group with a median (IQR) gestational age of 39.1 (38.8-39.3) weeks and a birth weight of 3,155 (2,970-3,472) grams were compared to 12 neonates in the non-smoking group with 39.1 (38.7-39.2) weeks and 3,134 (2,963-3,465) grams. In the smoking group, crSO2 was significantly lower and cFTOE significantly higher until min 5 after birth. HR was significantly higher in the smoking group in min 3 after birth. Beyond this period, there were no significant differences between the two groups. Conclusion: Cerebral oxygenation within the first 5 min after birth was compromised in neonates with prenatal tobacco exposure. This observation suggests a higher risk for cerebral hypoxia immediately after birth due to fetal tobacco exposure.

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.

Delivery Room Management of Asphyxiated Term and Near-Term Infants.

Approximately 800,000 newborns die annually due to birth asphyxia. The resuscitation of asphyxiated term newly born infants often occurs unexpected and is challenging for healthcare providers as it demands experience and knowledge in neonatal resuscitation. Current neonatal resuscitation guidelines often focus on resuscitation of extremely and/or very preterm infants; however, the recommendations for asphyxiated term newborn infants differ in some aspects to those for preterm infants (i.e., respiratory support, supplemental oxygen, and temperature management). Since the update of the neonatal resuscitation guidelines in 2015, several studies examining various resuscitation approaches to improve the outcome of asphyxiated infants have been published. In this review, we discuss current recommendations and recent findings and provide an overview of delivery room management of asphyxiated term newborn infants.

Impact of bradycardia and hypoxemia on oxygenation in preterm infants requiring respiratory support at birth.

AIM OF THE STUDY: Analysis of the impact of bradycardia and hypoxemia on the course of cerebral and peripheral oxygenation parameters in preterm infants in need for respiratory support during foetal-to-neonatal transition. METHODS: The first 15 min after birth of 150 preterm neonates in need for respiratory support born at the Division of Neonatology, Graz (Austria) were analyzed. Infants were divided into different groups according to duration of bradycardia exposure (no Bradycardia, brief bradycardia <2 min, and prolonged bradycardia ≥2 min) and to systemic oxygen saturation (SpO2) value at 5 min of life (<80% or ≥80%). Analysis was performed considering the degree of bradycardia alone (step 1) and in association with the presence of hypoxemia (step 2). RESULTS: In step 1, courses of SpO2 differed significantly between bradycardia groups (p = 0.002), while courses of cerebral regional oxygen saturation (crStO2) and cerebral fractional tissue oxygen extraction (cFTOE) were not influenced (p = 0.382 and p = 0.878). In step 2, the additional presence of hypoxemia had a significant impact on the courses of SpO2 (p < 0.001), crStO2 (p < 0.001) and cFTOE (p = 0.045). CONCLUSION: Our study shows that the degree of bradycardia has a significant impact on the course of SpO2 only, but when associated with the additional presence of hypoxemia a significant impact on cerebral oxygenation parameters was seen (crStO2, cFTOE). Furthermore, the additional presence of hypoxemia has a significant impact on FiO2 delivered. Our study emphasizes the importance of HR and SpO2 during neonatal resuscitation, underlining the relevance of hypoxemia during the early transitional phase.

Delayed cord clamping in healthy term infants: More harm or good?

It is recommended to delay cord clamping in healthy term infants for at least 60- and 180-s in high- and limited-resource environments, as delayed cord clamping lowers the incidence of anemia and iron deficiency and improves neurodevelopment. There are improvements in hemodynamic parameters such as peripheral arterial oxygen saturation, heart rate, cardiac output, and cerebral oxygenation. Historically, delayed cord clamping caused a higher rate of hyperbilirubinemia and phototherapy, but more recent evidence suggests this may no longer be the case. In limited-resource environments delayed cord clamping may reduce anemia and iron deficiency potentially improving neurodevelopmental outcomes. The use of delayed cord clamping in newborn infants with intrauterine growth restriction or monochorionic twins is limited and further evidence is needed before it can be formally recommended.

Effects of varying chest compression depths on carotid blood flow and blood pressure in asphyxiated piglets.

BACKGROUND: Current neonatal resuscitation guidelines recommend chest compressions (CCs) should be delivered to a depth of approximately 1/3 of the anterior-posterior (AP) chest diameter. The aim of the study was to investigate the haemodynamic effects of different CC depths in a neonatal piglet model. METHODS: CCs were performed with an automated CC machine with 33%, 40% and 25% AP chest diameter in all piglets in the same order for a duration of 3 min each. RESULTS: Eight newborn piglets (age 1-3 days, weight 1.7-2.3 kg) were included in the study. Carotid blood flow (CBF) and systolic blood pressure were the highest using a CC depth of 40% AP chest diameter (19.3±7.5 mL/min/kg and 58±32 mm Hg). CONCLUSION: CC depth influences haemodynamic parameters in asphyxiated newborn piglets during cardiopulmonary resuscitation. The highest CBF and systolic blood pressure were achieved using a CC depth of 40% AP chest diameter. TRIAL REGISTRATION NUMBER: PCTE0000148.