Oxygen saturation in healthy newborn infants immediately after birth measured by pulse oximetry

Falls in oxygen saturations accompany electrographic seizures in term neonates: an observational study

BACKGROUND

Effective seizure detection is important however, clinical signs of seizure activity may be subtle in neonates. This study aimed to systematically investigate SpO2 and respiratory pattern changes associated with EEG seizures in term-born neonates.

METHOD

An observational study in term neonates at risk of seizures admitted to a single tertiary level neonatal intensive care unit. Synchronised high-resolution physiological data (ECG, pulse oximetry, respiration) and EEG/amplitude-integrated EEG (aEEG) monitoring were recorded. Sections of traces with evidence of clear EEG seizure activity were compared with physiological data recorded at the same time.

RESULTS

22/44 (50%) neonates who had aEEG monitoring were noted to have electrographic seizures. Physiologic download measurements were available for 11 of these neonates. In nine of these, an acute drop in oxygen saturation (SpO2) of at least 5% was noted in at least one seizure. Accompanying apnoeas were noted in three neonates.

CONCLUSION

Acute decreases in SpO2 were seen in term neonates associated with seizures and these were not always accompanied by an apnoeic episode. Physiologic download in association with EEG monitoring may assist in improving seizure detection. Unexplained drops in SpO2 could indicate further investigation for possible seizures in at-risk neonates.

IMPACT

A decrease in blood oxygen saturation (SpO2) associated with EEG seizures can occur in term infants with HIE or perinatal stroke. Drops in SpO2 associated with EEG seizures in term infants with HIE or stroke may occur in the absence of apnoeas. Unexplained acute falls in SpO2 in sick neonates may suggest possible seizures. Drops in SpO2 associated with seizures in term infants can occur over less than 3 minutes. Physiological monitoring alongside EEG monitoring could help to improve seizure detection.

Oxygen saturation centiles in healthy preterm neonates in the first 10 min of life: a prospective observational study

Current oxygen saturation targets in delivery room given by Neonatal Resuscitation Program (NRP) are essentially derived from term neonates. This prospective observational study was conducted in a level-III neonatal unit in preterm neonates (< 37 weeks) who did not receive resuscitation or supplemental oxygen to create centile charts for pre-ductal oxygen saturations using robust statistical modelling methods. Pre-ductal oxygen saturations (SPO2) were recorded from birth till 10 min of age using current generation Masimo pulse oximeters. Centile charts were created by generalized additive models. The change in oxygen saturations over time across subjects was modelled as a Bayesian linear regression mixed-effects model after including 'a priori' covariates. Oxygen saturation data was analysed in 180 subjects with mean gestation of 34 ± 2 weeks. Mean (SD) time to first SPO2 was 167 ± 77 s. The median time to SPO2 of > 90% was 310 s (IQR: 235-400). Time to > 90% SPO2 was shorter in (a) 34-36 weeks compared to < 34 weeks (290 vs 340; p = 0.03) and (b) vaginally delivered compared to caesarean-section born neonates (300 vs 360; p = 0.2).    Conclusions: Oxygen saturations in first 10 min of age in healthy preterm neonates are significantly higher than the targets proposed by the NRP-2020. Larger preterm neonates and those born through vaginal route attained a preductal saturation of > 90% sooner. What is Known: • Pulse oximetry is the standard for oxygen saturation monitoring during immediate postnatal period. • Healthy term neonates take many minutes after birth to reach a pre-ductal saturation of >90%. But, postnatal oxygen saturation trend data in healthy preterm neonates are scarce. What is New: • Provides centile charts for oxygen saturations till 10 minutes of age using current generation Masimo pulse oximeters in a large cohort of healthy preterm neonates using robust statistical modelling methods. • Identifies covariates that significantly modifies the saturation trends using a Bayesian mixed models' regression.

Cardiovascular fetal-to-neonatal transition: an in silico model

BACKGROUND

Previous models describing the fetal-to-neonatal transition often lack oxygen saturation levels, homeostatic control mechanisms, phasic hemodynamic signals, or describe the heart with a time-varying elastance model.

METHODS

We incorporated these elements in the adapted CircAdapt model with the one-fiber model for myocardial contraction, to simulate the hemodynamics of the healthy term human fetal circulation and its transition during the first 24 h after birth. The fetal-to-neonatal model was controlled by a time- and event-based script of changes occurring at birth, such as lung aeration and umbilical cord clamping. Model parameters were based on and validated with human and animal data.

RESULTS

The fetal circulation showed low pulmonary blood flow, right ventricular dominance, and inverted mitral and tricuspid flow velocity patterns, as well as high mean ductus venosus flow velocity. The neonatal circulation showed oxygen saturation levels to gradually increase to 98% in the first 15 min after birth as well as temporary left ventricular volume overload.

CONCLUSIONS

Hemodynamics of the term fetus and 24-h-old neonate, as well as the events occurring directly after birth and the transition during the first 24 h after birth, were realistically represented, allowing the model to be used for educational purposes and future research.

IMPACT

With the addition of oxygen saturation levels, homeostatic pressure-flow control mechanisms, and the one-fiber model for myocardial contraction, a new closed-loop cardiovascular model was constructed to give more insight into the healthy term human fetal circulation and its cardiovascular transition during the first 24 h after birth. Extensive validation confirmed that the hemodynamics of the term fetus and the fetal-to-neonatal transition were realistically represented with the model. This well-validated and versatile model can serve as an education as well as a research platform for in silico investigation of fetal-to-neonatal hemodynamic changes under a wide range of physiological and pathophysiological conditions.

Oxygen in the First Minutes of Life in Very Preterm Infants

Even a few minutes of exposure to oxygen in the delivery room in very preterm and immature infants may have detrimental effects. The initial oxygenation in the delivery room should therefore be optimized, but knowledge gaps, including initial fraction of oxygen (FiO2) and how FiO2 should be changed to reach an optimal oxygen saturation measured by pulse oximetry (SpO2) target within the first 5-10 min of life, remain. In order to answer this question, we therefore reviewed relevant literature. For newly born infants with gestational age (GA) <32 weeks in need of positive pressure ventilation (PPV) immediately after birth, we identified 2 fundamental issues: (1) the optimal initial FiO2 and (2) the target SpO2 within the first 5-10 min of life. For newly born infants between 29 and 31 weeks of GA, an initial FiO2 of 0.3 hit the target defined by the International Liaison Committee on Resuscitation (ILCOR) best. Newborn infants with GA <29 weeks in need of PPV and supplementary oxygen, we suggest starting with FiO2 0.3 and adjusting the FiO2 to reach SpO2 of 80% within 5 min of life for best outcomes. Prolonged bradycardia (heart rate <100 bpm for >2 min) is associated with increased risk of adverse outcomes, including death. The combination of strict control of development of SpO2 in the first 10 min of life and a heart rate >100 bpm represents the best tool today to achieve the most optimal outcome in the delivery room of very preterm and immature newborn infants.

Reference Interval for Pulse Oxygen Saturation in Neonates at Different Altitudes: A Systematic Review

Introduction: The reference interval for pulse oxygen saturation (SpO₂) in neonates born at high altitudes has not been defined to date. The purpose of this study was to systematically review published studies and determine the reference interval of SpO₂ in neonates at different altitudes. Methods: Databases of PubMed, Embase, Cochrane Library, Clinicaltrials.Gov, Chinese National Knowledge Infrastructure Database, Wanfang Database, Chinese Science Technology Journals Database, and Chinese Clinical Trial Registry were searched for studies reporting SpO₂ in healthy neonates at different altitudes. Retrieval time was from inception of the database to August 16, 2021. The Agency for Healthcare Research and Quality checklist was used to evaluate the quality of studies. Python v3.8 was used to analyze the data. This systematic review was drafted in accordance with the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Results: Seven cross-sectional studies, published between 1991 and 2020, were identified. They were from US, Mexico, Israel, Ecuador, and China. Three studies were rated as high quality and four as moderate quality. The mean SpO₂ (with standard deviation or standard error) of neonates born in 40 different altitudes (ranging from 25 meters to 3,100 meters) were obtained. The prediction equation for calculation of the lower limit of the reference interval was established, and the reference intervals for SpO₂ at different altitudes were determined. Conclusions: In healthy neonates, the lower limit of the reference interval of SpO₂ decreases with increase in altitude. High-quality prospective studies are need to confirm our findings.

Delayed vs Immediate Cord Clamping Changes Oxygen Saturation and Heart Rate Patterns in the First Minutes after Birth

OBJECTIVE

To build arterial oxygen saturation (SpO₂) and heart rate (HR) percentiles for the first 10 minutes after birth in term infants born after an uneventful gestation, vaginal delivery, and delayed cord clamping (DCC) for ≥60 seconds, and to compare our results with previous ones constructed after immediate cord clamping.

STUDY DESIGN

Preductal SpO₂, HR, and timing of DCC immediately after complete fetal body expulsion were recorded. The pulse-oximeter was adjusted in the right wrist/hand and set at maximal intensity and measurements performed every 2 seconds.

RESULTS

A total of 282 term newborn infants were included. The definitive data set comprised of 70 257 SpO₂ and 79 746 HR measurements. Median and IQR of SpO₂ (%) at 1, 5, and 10 minutes after birth were 77 (68-85), 94 (90-96), and 96 (93-98), respectively. HR (beats per minute) median and IQR at 1, 5, and 10 minutes after birth were 148 (84-170), 155 (143-167), and 151 (142-161), respectively. We found significantly higher SpO₂ for the 10th, 50th, and 90th percentiles compared with the previous reference ranges for the first 5 minutes and HR for the first 1-2 minutes after birth.

CONCLUSIONS

Spontaneously breathing term newborn infants born by vaginal delivery who underwent DCC ≥60 seconds achieved higher SpO₂ and HR in the first 5 minutes after birth compared with term neonates born under the same conditions but with immediate cord clamping. Further studies in neonates undergoing cesarean delivery are under way.

Practical oxygen therapy for newborn piglets

Aims: To evaluate the effect of a novel method of practical oxygen therapy on physiological parameters related to survival, weaning weight and preweaning mortality of neonatal piglets under commercial farm conditions. Methods: Piglets from hyperprolific sows born with signs of asphyxia, (n = 109; <6 on a score of respiration, meconium staining and activity) or very low birth weight (VLBW; n = 112; <1.05 kg) were selected for the study. Approximately half of each group (n = 55 VLBW piglets and n = 57 piglets with asphyxia) received 100% oxygen immediately after birth using a specially designed facemask for 45 seconds (VLBW) or 1 minute (asphyxiated). Physiological parameters (peripheral blood oxygen saturation (SpO₂) blood glucose concentration and rectal temperature) were measured before oxygen treatment 5 minutes after birth (SpO₂) and 24 hours later (SpO₂, blood glucose concentration, temperature). Weight at birth, at 24 hours and at 21 days of age, preweaning mortality, and estimated colostrum intake were also recorded. Results: A significant treatment effect on SpO₂ was observed (p = 0.013 and p < 0.001 for VLBW and asphyxiated piglets respectively). VLBW and asphyxiated piglets that received oxygen treatment had higher SpO₂ after treatment (measured 5 minutes after birth, 97.7 and 97.8% respectively) compared to immediately after birth (93.3 and 86.8% respectively) while untreated piglets showed no variation. Blood glucose concentrations increased in all piglets between birth and 24 hours of age (p = 0.003 and p < 0.001 for asphyxiated and VLBW piglets respectively) and this was higher in asphyxiated piglets that received oxygen than those that did not (5.6 (SE 0.2) mmol/L; p < 0.05). Estimated colostrum intake was higher in asphyxiated (401.6 (SD 24.4) g/kg) and VLBW (374.9 (SE 23.4 g/kg) piglets that received oxygen than those that did not (273.2 (SE 24.1) g/kg; p < 0.001 and 249.0 (SE 22.5) g/kg; p < 0.001 respectively). Similarly weight at weaning was higher in asphyxiated (5.8 (SE 0.2) kg) and VLBW (4.9 (SE 0.2) kg) piglets that received oxygen therapy than control animals (4.9 (SE 0.2) kg; = 0.005 and 4.1 (SE 0.2) kg; p = 0.008 respectively). Furthermore, oxygen treatment markedly reduced preweaning mortality from 9/52 (17%) untreated to 1/57 (1.7%) oxygen-treated piglets suffering asphyxia at birth (p = 0.006). Conclusions: Oxygen therapy improves physiological and productive parameters in piglets born with signs of asphyxia or VLBW. The incorporation of this strategy as part of the farrowing routine enhances the advantages of rearing hyperprolific sows.

Is There a "Right" Amount of Oxygen for Preterm Infant Stabilization at Birth?

The amount of oxygen given to preterm infants within the first few minutes of birth is one of the most contentious issues in modern neonatology. Just two decades ago, pure oxygen (FiO2 1.0) was standard of care and oximetry monitoring was not routine. Due to concerns about oxidative stress and injury, clinicians rapidly adopted the practice of using less oxygen for the respiratory support of all infants, regardless of gestational maturity and pulmonary function. There is now evidence that initial starting fractional inspired oxygen may not be the only factor involved in providing optimum oxygenation and that the amount of oxygen given to babies within the first 10 min of life is a crucial factor in determining outcomes, including death and neurodevelopmental injury. In addition, evolving practice, such as non-invasive respiratory support and delayed cord clamping, need to be taken into consideration when considering oxygen delivery to preterm infants. This review will discuss evidence to date and address the major knowledge gaps that need to be answered in this pivotal aspect of neonatal practice.

Newborn Resuscitation in Settings Without Access to Supplemental Oxygen

Low- and middle-income countries and resource-limited regions are major contributors to perinatal and infant mortality. Oxygen is widely used for resuscitation in high- and middle-income settings. However, oxygen supplementation is not available in resource-limited regions. Oxygen supplementation for resuscitation at birth has adverse effects in human/animal model studies. There has been a change with resultant recommendations for restrictive oxygen use in neonatal resuscitation. Neonatal resuscitation without supplemental oxygen decreases mortality and morbidities. Oxygen in resource-limited settings for neonatal resuscitation is ideal as a backup for selected resuscitations but should not be a limiting factor for implementing basic life-saving efforts.

Effects of pharyngeal suction on the arterial oxygen saturation and heart rate in healthy newborns delivered by elective cesarean section

OBJECTIVE

To evaluate the effect of oro-and naso- pharyngeal suction (ONPS) on the SpO2 and heart rate (HR) in healthy term newborns delivered by cesarean section, at the first minutes after birth.

PATIENTS AND METHODS

We conducted a prospective randomized trial. Newborns were randomized to ONPS and No-ONSP groups. Continuous readings of SpO2 and HR were performed during the first 10 minutes, and subsequently at 15, 30 and 60 minutes after birth.

RESULTS

A total of 84 newborns were evaluated; 42 in ONPS group and 42 in No-ONPS group, with mean gestational age and birth weight±SD of 38.4 weeks and 3533±403 g in the ONPS group and 38.0 weeks and 3575±568 g in the No-ONPS group. The mean SpO2±SD at the first minute of life in the former group was 52.6±7.6% vs 56.1±10.8% on the latter; with no significant difference (p = 0.28). The mean HR±SD at first minute of life was 137±25 in the No-ONPS and 148±13 in the ONPS group (p = 0.02), but no difference was found in the subsequent minutes.

CONCLUSION

Not performing ONPS in newborns delivered by cesarean section does not affect SpO2 and HR in the first postpartum hour.

Monitoring heart rate in the delivery room

Resuscitation algorithms and guidelines highlight the importance of heart rate (HR) in determining interventions and assessing their effect. However, the actual HR values used are historical based upon normal physiology, and HR at birth may be affected by mode of delivery and timing of cord clamping as well as respiratory status and condition at delivery. Furthermore, the most accurate and effective ways to assess and monitor HR in the newborn infant are only now becoming established. This article examines the importance of HR values and the most widely used methods of estimation as well as some newer modalities which are being developed.

Role of Pulse Oximetry Screening for Detection of Life Threatening Congenital Heart Detects in Newborn

Most ofnewborns with Congenital Heart Defects (CHDs) can be detected by using echocardiography. However, if such defects are not diagnosed in earlier time, therefore a severe hypoxemia, shock, acidosis and death are considered of some potential sequelae. A prospective study from January 2012 to the end of 2013 was performed and 2181 neonates were enrolled in the study. The pulse oximetry screening (POS) for both hands and one foot were obtained within the first 3-6 hours of life, when post ductal saturation was below 90%, it was considered as a positive screening, while when the saturation is between 90-95% and the difference between pre-and post-ductal saturation was more than 3%, the baby was provisionally considered to be screening as a positive then echocardiography is planned. Among 100 positive POS babies, 45 (45%) of them were detected with CHS, 12 (12%) was with a major CHS and 33 (33%) was with a minor CHS. Out of 12 patients with a major CHD 6 of them (50%) were asymptomatic at the time of POS.POS result was a true negative in 2078 patients, a true positive in 45 patients, false negative in 3 patients, and false positive in 55 and 28/55 of the false positive rate with POS had other pathology. The false positive rate with pulse oximetry screening is (55/2081) = 0.26%. Sensitivity, specificity, positive and negative predictive value for POS in detection of major CHD were 80%, 97.29%, 17.9% and 99.80%, respectively. Pulse oximetry screening is significantly improving the detection of life threatening congenital heart disease at an early stage.

Heart rate variability in healthy term newborns is related to delivery mode: a prospective observational study

Background

Early postnatal period is characterized by dramatic adaptation changes of cardiovascular and respiratory systems in newborns. There is still insufficient data regarding maturation of autonomic regulatory mechanisms in neonates early after delivery. Aim of this study was to analyze cardiac autonomic regulation in newborns within the first few postnatal days in relation to different modes of delivery using time and spectral heart rate variability analysis.

Methods

Eutrophic healthy term newborns (n = 46) were divided into three groups according to the delivery mode: vaginal delivery (VD group; n = 16), vaginal delivery with epidural analgesia (EDA group; n = 16), and caesarean section under general anesthesia (CS group; n = 14). Heart rate variability (HRV), blood pressure (BP), and blood oxygen saturation (SpO₂) were measured within the first two hours after birth and on the third to fourth postnatal day. HRV parameters were evaluated in the time domain (RR intervals, mean square of successive differences – MSSD) and frequency domain (total spectral power – TP, absolute and relative low and high frequency powers).

Results

The HRV spectral analysis showed significantly higher relative power of the high-frequency band (HF%) in the VD group compared to the CS group early after delivery (p = 0.002). HRV parameters and BP significantly increased on the third to fourth postnatal day in all groups (p < 0.05). No significant differences in basic characteristics, BP and SpO₂ were identified between groups during both measurements.

Conclusions

HRV analysis revealed higher cardiovagal modulation in spontaneously born newborns without analgesia compared to neonates born by caesarean section. It could represent a potential pathomechanism that leads to discrete abnormal neurocardiac regulation associated with higher risk for worsened postnatal adaptation of cardiovascular system in surgically delivered neonates.

Heart Rate Variability in Newborns

Heart rate (HR) and heart rate variability (HRV) in newborns is influenced by genetic determinants, gestational and postnatal age, and other variables. Premature infants have a reduced HRV. In neonatal HRV evaluated by spectral analysis, a dominant activity can be found in low frequency (LF) band (combined parasympathetic and sympathetic component). During the first postnatal days the activity in the high frequency (HF) band (parasympathetic component) rises, together with an increase in LF band and total HRV. Hypotrophy in newborn can cause less mature autonomic cardiac control with a higher contribution of sympathetic activity to HRV as demonstrated by sequence plot analysis. During quiet sleep (QS) in newborns HF oscillations increase – a phenomenon less expressed or missing in premature infants. In active sleep (AS), HRV is enhanced in contrast to reduced activity in HF band due to the rise of spectral activity in LF band. Comparison of the HR and HRV in newborns born by physiological vaginal delivery, without (VD) and with epidural anesthesia (EDA) and via sectio cesarea (SC) showed no significant differences in HR and in HRV time domain parameters. Analysis in the frequency domain revealed, that the lowest sympathetic activity in chronotropic cardiac chronotropic regulation is in the VD group. Different neonatal pathological states can be associated with a reduction of HRV and an improvement in the health conditions is followed by changes in HRV what can be use as a possible prognostic marker. Examination of heart rate variability in neonatology can provide information on the maturity of the cardiac chronotropic regulation in early postnatal life, on postnatal adaptation and in pathological conditions about the potential dysregulation of cardiac function in newborns, especially in preterm infants.

Factors Affecting the Target Oxygen Saturation in the First Minutes of Life in Preterm Infants

BACKGROUND

The aim of this study was to describe the effect of factors on time to reach a pulse oxygen saturation (SpO2) level of 90% in preterm infants in the delivery room.

METHODS

Preterm (<35 gestational age) infants who did not require supplemental oxygen were included in the study. Continuous recordings were taken by pulse oximetry during the first 15 min of life.

RESULTS

Of 151 preterm infants, 79 (52.3%) were female and 126 (83.5%) were delivered by cesarean section. Target saturation level (≥90%) was achieved faster in preductal measurements. Mean times taken to have a preductal and postductal SpO2 level of 90% were significantly lower in preterm babies born by vaginal delivery, with umbilical arterial pH ≥ 7.20 and whose mothers were non-smokers during pregnancy.

CONCLUSIONS

Differences in achievement of target saturation level were influenced by multiple factors (birth way, probe location, maternal smoking and umbilical blood gas pH) in the delivery room during resuscitation of preterm babies.

Oxygen Saturation and Heart Rate Ranges in Very Preterm Infants Requiring Respiratory Support at Birth

OBJECTIVE

To evaluate the changes in preductal oxygen saturation (SpO₂) and heart rate in preterm infants receiving continuous positive airway pressure (CPAP) and/or positive-pressure ventilation (PPV) at birth.

STUDY DESIGN

A prospective observational study at birth of infants aged <32 weeks separated into 2 gestational age (GA) groups: 23^0/7-27^6/7 weeks (group 1) and 28^0/7-31^6/7 weeks (group 2). Infants received delayed cord clamping (DCC) in accordance with institutional protocol. CPAP and/or PPV was applied at the clinical team's discretion. SpO₂ and heart rate were recorded every minute for 10 minutes. Preductal SpO₂ was targeted according to published nomograms. For heart rate, the goal was to maintain a stable heart rate >100 bpm.

RESULTS

The study cohort comprised 96 group 1 infants (mean GA, 26 ± 1 weeks; mean birth weight, 818 ± 208 g) and 173 group 2 infants (mean GA, 30 ± 1 weeks; mean birth weight, 1438 ± 374 g). In general, infants requiring respiratory support reached target values for heart rate and SpO₂ more slowly than the published nomograms for spontaneously breathing preterm infants without respiratory support. Infants receiving CPAP reached SpO₂ and heart rate targets faster than infants receiving PPV. In group 1, but not group 2 infants, DCC resulted in higher SpO₂ and heart rate.

CONCLUSION

SpO₂ and heart rate do not quickly and reliably reach the values achieved by spontaneously breathing preterm infants not requiring respiratory support.

Arterial oxygen saturation and heart rate after birth in newborns with and without maternal bonding

BACKGROUND

The aim of this study was to determine and compare changes in arterial oxygen saturation (SpO₂ ) and heart rate (HR) in healthy term infants with and without maternal bonding.

METHOD

This was a prospective observational study in healthy term infants. SpO₂ and HR were recorded from 1 to 10 min after birth. After this, SpO₂ and HR were registered at 15, 30 and 60 min and then at 12 and 24 h after birth. SpO₂ and HR were measured with a pulse oximeter.

RESULTS

A total of 216 healthy term infants were divided into three different groups: 136 (63%) born by vaginal delivery, 56 (26%) born by cesarean section with bonding, and 24 (11%) born by cesarean section without bonding. No difference in SpO₂ was found in babies born by cesarean section with or without maternal bonding. In neonates delivered vaginally, SpO₂ was significantly higher during the first 10 min after birth than in neonates born by cesarean section with bonding (P < 0.05). Compared with infants born by cesarean section without bonding, this tendency was not significant. In general, HR was similar across groups, although, for infants born by cesarean section, neonates who received bonding had lower HR from 6 to 8 min (P < 0.05).

CONCLUSIONS

In healthy term newborns, maternal bonding in infants born by cesarean section did not have effects on SpO₂ . Some differences were observed in HR between infants born by cesarean section with and without bonding.

Neonatal echocardiography

Echocardiography is a technique within neonatal care increasingly used in acute management of patients because of its potential to guide care and hemodynamic management. However, its use continues to provoke controversy, as it was originally within the purview of pediatric cardiologists trained to identify structural as well as functional heart disease. This article examines some of the echocardiographic techniques available to the neonatologist, their applications, and the concerns surrounding their use on neonatal units.

Low signal quality pulse oximetry measurements in newborn infants are reliable for oxygen saturation but underestimate heart rate

AIM

We assessed the influence of system messages (SyMs) on oxygen saturation (SpO2 ) and heart rate measurements after birth to see whether clinical decision-making changed if clinicians included SyM data.

METHODS

The heart rate and SpO2 of term infants were recorded using Masimo pulse oximeters. Differences in means and standard deviations (SD) were calculated. Permutation corrected the nonrandom distribution and intersubject variation. SpO2 and heart rate centile charts were computed with, and without, SyMs.

RESULTS

Pulse oximetry measurements from 117 neonates provided 28 477 data points. SyMs occurred in 46% of measurements. Low signal quality accounted for 99.9% of SyMs. The mean SpO2 was lower with SyMs (p < 0.001), while the SpO2 SD was similar to data without SyMs. The SpO2 centile charts were approximately 2% lower with SyMs included, but they were not more dispersed. Mean heart rate was lower (p < 0.001) and more dispersed (p < 0.001) when a SyM occurred. The heart rate centile charts were lower, with increased variability, when SyMs were included.

CONCLUSION

A SyM occurred frequently during pulse oximetry in term infants after birth. SpO2 measurements with low signal quality proved reliable for monitoring an infant's clinical condition. However, heart rate could be underestimated by low signal quality measurements.

Cardiocirculatory monitoring during immediate fetal-to-neonatal transition: a systematic qualitative review of the literature

BACKGROUND

The fetal-to-neonatal transition is a complex process that includes changes in cardiac and respiratory systems.

OBJECTIVE

The aim of this study is to review the different methods of cardiocirculatory monitoring during the immediate neonatal transition period.

METHODS

A systematic search of PubMed and Ovid Embase was performed using the following terms: infant, newborn, newborn infant, neonate, neonates, heart, cardiac, blood pressure, haemodynamic, hemodynamics, blood circulation, circulation, echocardiography, ultrasonography, sonography, electrocardiography, ECG, oximetry, pulse, pulse oximetry, monitoring, measurement, acclimatization, adaptation, transition, after birth and delivery room. Additional articles were identified by manual search of cited references. Only human studies describing cardiocirculatory monitoring during the first 15 min after birth were included.

RESULTS

Thirteen studies were identified that described heart rate (HR). Additional five studies were identified that measured blood pressure. Four studies performed functional echocardiography during neonatal transition; two in addition to blood pressure monitoring and three in addition to HR monitoring.

CONCLUSION

Routine HR monitoring using electrocardiography or pulse oximetry is used to evaluate adequate hemodynamic transition, and reference ranges have been established. Measuring blood pressure noninvasively though noncontinuously might be of some value in future, considering that the normative data have been established recently. Echocardiographic monitoring during the immediate transition period will improve the knowledge about cardiac function changes, but introduction in clinical routine remains questionable.

Reevaluating reference ranges of oxygen saturation for healthy full-term neonates using pulse oximetry

BACKGROUND

We compared our clinical experience with currently available reference oxygen saturation level (SpO(2)) values from the American Academy of Pediatrics/American Heart Association (AAP/AHA) neonatal resuscitation program guidelines.

METHODS

We enrolled 145 healthy full-term neonates; infants showing respiratory distress and those with serious congenital anomalies were excluded. SpO(2) values at every 1 minute until 10 minutes after birth were measured and recorded. Infants were classified into the cesarean section (CS) and normal spontaneous delivery (NSD) groups for evaluating differences. The 10(th) percentiles of SpO(2) at each minute were used as the lower limits of normal oxygen saturation, and these were compared with the lowest target values recommended in the AAP/AHA guidelines.

RESULTS

Overall, 130 vigorous full-term neonates (median gestational age: 38 5/7 weeks; body weight at birth: 2405-3960 g) were analyzed. The median SpO(2) were 67% and 89% at the 1(st) and 4(th) minute, respectively. On average, SpO(2) values reached >90% at the 5(th) minute. No statistical differences were noted in the SpO(2) values between the CS and NSD groups after 5 minutes; however, a trend of higher SpO(2) was observed in the NSD group. We noted a gradually increasing trend for SpO(2) values over time, similar to that noted in the AAP/AHA guidelines. However, SpO(2) values at the 10(th) percentiles of each minute within the first 5 minutes in our study were equal to or significantly lower than those in the AAP/AHA guidelines; moreover, at the 10(th) minute, SpO(2) values at the 10(th) percentiles were significantly higher than those in the guidelines.

CONCLUSION

The delivery modes did not affect the SpO(2) values of full-term healthy neonates. Discrepancies in SpO(2) changes in full-term neonates not requiring resuscitation between this study and the AAP/AHA guidelines were significant. SpO(2) ranges for each time point within the first 10 minutes after birth should therefore be reevaluated locally.

Development of a luminous textile for reflective pulse oximetry measurements

In this paper, a textile-based sensing principle for long term photopletysmography (PPG) monitoring is presented. Optical fibers were embroidered into textiles such that out-coupling and in-coupling of light was possible. The "light-in light-out" properties of the textile enabled the spectroscopic characterization of human tissue. For the optimization of the textile sensor, three different carrier fabrics and different fiber modifications were compared. The sample with best light coupling efficiency was successfully used to measure heart rate and SpO2 values of a subject. The latter was determined by using a modified Beer-Lambert law and measuring the light attenuation at two different wavelengths (632 nm and 894 nm). Moreover, the system was adapted to work in reflection mode which makes the sensor more versatile. The measurements were additionally compared with commercially available system and showed good correlation.

Pulse oximetry in newborns with delayed cord clamping and immediate skin-to-skin contact

OBJECTIVE

To assess whether defined reference ranges of oxygen saturation (SpO₂) and heart rate (HR) of term infants after birth also apply for infants born after midwifery supervised uncomplicated vaginal birth, where delayed cord clamping (DCC) and immediate skin to skin contact (ISSC) is routine management.

DESIGN

Prospective observational study.

SETTING AND PATIENTS

Infants born vaginally after uncomplicated birth, that is, no augmentation, maternal pain relief or instrumental delivery.

INTERVENTIONS

Midwives supervising uncomplicated birth at home or in hospital in the Leiden region (The Netherlands) used an oximeter and recorded SpO₂ and HR in the first 10 min after birth.

MAIN OUTCOME MEASURES

SpO₂ and HR values were compared to the international defined reference ranges.

RESULTS

In Leiden, values of 109 infants were obtained and are comparable with previously defined reference ranges, except for a higher SpO₂ (p<0.05) combined with a slower increase in the first 3 min. The Leiden cohort also had a lower HR (p<0.05) during the first 10 min with a slower increase in the first 3 min. In the first minutes after birth, tachycardia (HR>180 bpm) occurred less often, and a bradycardia (<80 bpm) more often (p<0.05).

CONCLUSIONS

Defined reference ranges can be used in infants born after uncomplicated vaginal birth with DCC and ISSC, but higher SpO₂ and lower HR were observed in the first minutes.

Oxygen saturation immediately after birth in infants delivered in tertiary care hospital in India

OBJECTIVE

To study the sequential changes in SpO2 values in newborns delivered in a teaching hospital in India.

METHODS

Full-term infants born by normal vaginal delivery to registered mothers at KLE University Hospital, Belgaum with birth weight more than 2,500 g, no congenital anomalies and who had received only routine care at birth were included in the study. After delivery, newborn infants were placed on a resuscitation trolley under a radiant warmer; the oxygen saturation sensor was attached (Nellcor DURA-Y multisite oxygen sensor) and then connected to the monitor (Planet 55 multiparameter recorder).

RESULTS

The mean (SD) gestational age of infants included in the study was 38.8 (1.1) wk and birth weight was 2,800 (300) g. The median (IQR) oxygen saturation level (SpO2) at 2 min of age was 69 % (68 %-79 %). The median level of SpO2 at 90 % and 95 % saturation was attained at 6.5 min and at 11 min of life, respectively.

CONCLUSIONS

Infants delivered in resource poor facilities of developing countries take 11 min to reach 95 % saturations after birth but they are within the reference range values of Neonatal Resuscitation Program 2010 guidelines.

Changes in cerebral oxygenation during early postnatal adaptation in newborns delivered by vacuum extraction measured by near-infrared spectroscopy

Background

Newborns delivered by vacuum extraction quite often show clinical signs of a hemodynamic compromise, which is difficult to assess in terms of severity. The conventional means to measure the hemodynamic status are not sensitive enough to appreciate the severity of general, and more specifically of cerebral circulatory imbalance. The aim was to study cerebral tissue oxygenation during postnatal adaptation in these infants using near-infrared spectroscopy.

Methods

The tissue hemoglobin index (THI), tissue oxygenation index (TOI), arterial oxygen saturation (pre-ductal SaO₂) and heart rate (HR) were recorded immediately after birth, and again after 12–24 hours of life in 15 newborns delivered by vacuum extraction due to fetal distress. A comparison with 19 healthy newborns delivered by elective cesarean section was performed.

Results

Newborns delivered by vacuum extraction had significantly higher THI 10 to 15 minutes after birth. TOI and HR were significantly higher in the first 5 min and SaO₂ in the first 10 minutes but then did not differ from those after cesarean section.

Conclusion

Infants delivered by vacuum extraction following fetal distress show transient deviations in cerebral oxygenation and perfusion after birth which were not detectable after 24 hours.

Oxygen saturation trends in the first hour of life in healthy full-term neonates born at moderate altitude

Background: Transition from a parallel circulation in utero to an in-series circulation immediately after birth is partly an oxygen-dependent process. Relative hypoxemia with increasing altitude above sea level exerts a certain degree of stress on oxygen-dependent metabolic processes throughout the body.

Objective: The present study aimed to determine the reference values for oxygen saturation and the pre-ductal and post-ductal oxygen saturation trends during the first 60 min of life in healthy full-term neonates born at moderate altitude (1500-2500 m) using pulse oximetry.

Methods: This descriptive study was carried out over a period of three months started from July 2011 in the Neonatology Department of King Abdulaziz Specialist Hospital, Taif, Saudi Arabia. In this observational study, arterial oxygen saturation in the right hand and right foot of each infant was recorded by pulse oximetry immediately after birth and continuously within the first 60 min of life. The respiratory rate, heart rate, and blood pressure were measured at birth and at 1 h after birth. Cord blood gas and haemoglobin levels were also measured.

Results: The study was conducted in a hospital situated at an altitude of 1640 m above sea level. Immediately after birth, the mean pre-ductal SpO₂ in the right hand was 68% (51–80%); in the right foot, the mean post-ductal SpO₂ was 60% (40–77%). This difference was statistically significant (p < 0.01); however, it became statistically insignificant at 20 min (4–45 min) and disappeared at 25 min, when the SpO₂ in both limbs equalised at 88% (83–96%). SpO₂ levels > 94% were reached after 13 min (4–35) min pre-ductally and after 22 min (10–45 min) post-ductally. The mean respiratory rate, heart rate, and mean blood pressure at birth were 56/min, 140/min, and 34 mmHg, respectively; at 60 min, they were 40/min, 123/min, and 47 mmHg, respectively.

Conclusion: This study defined normal range of SpO₂ values in healthy full-term neonates born at moderate altitude in the first 60 minutes of life. These are expected to serve as base line data for normal neonates born at similar altitudes. With regard to pre-ductal and post-ductal oxygen saturation levels, cut-off values lower than those used at sea level should be adopted for neonates born at moderate altitudes.

Oxygen therapy and oximetry in the delivery room

Pulse oximetry is increasingly being used in the delivery room. Expert recommendations state that oxygen therapy during newborn resuscitation should be guided by pulse oximetry. Obtaining accurate and stable oxygen saturation and heart rate information from a pulse oximeter in the delivery room can be challenging. Understanding the properties of this device is important in overcoming these challenges. This article describes several aspects of pulse oximetry use in the delivery room ranging from technical issues with the device itself to clinical applications of the technology.

Improving delivery room management for very preterm infants

BACKGROUND AND OBJECTIVES

Events in the delivery room significantly impact the outcomes of preterm infants. We developed evidence-based guidelines to prevent heat loss, reduce exposure to supplemental oxygen, and increase use of noninvasive respiratory support to improve the care and outcomes of infants with birth weight ≤1250 g at our institution.

METHODS

The guidelines were implemented through multidisciplinary conferences, routine use of a checklist, appointment of a dedicated resuscitation nurse, and frequent feedback to clinicians. This cohort study compares a historical group (n = 80) to a prospective group (n = 80, after guidelines were implemented). Primary outcome was axillary temperature at admission to the intensive care nursery. Secondary outcomes measured adherence to the guidelines and changes in clinically relevant patient outcomes.

RESULTS

Baseline characteristics of the groups were similar. After introduction of the guidelines, average admission temperatures increased (36.4°C vs 36.7°C, P < .001) and the proportion of infants admitted with moderate/severe hypothermia fell (14% vs 1%, P = .003). Infants were exposed to less oxygen during the first 10 minutes (P < .001), with similar oxygen saturations. Although more patients were tried on continuous positive airway pressure (40% vs 61%, P = .007), the intubation rate was not significantly different (64% vs 54%, P = .20). Median durations of invasive ventilation and hospitalization decreased after the quality initiative (5 vs 1 days [P = .008] and 80 vs 60 days [P = .02], respectively).

CONCLUSIONS

We have demonstrated significantly improved quality of delivery room care for very preterm infants after introduction of evidence-based delivery room guidelines. Multidisciplinary involvement and continuous education and reinforcement of the guidelines permitted sustained change.

Achieving targeted pulse oximetry values in preterm infants in the delivery room

OBJECTIVE

To determine whether resuscitation teams can better maintain newborn transitional oxygen saturation (SpO₂) values within a prespecified target range using a graphical display of the targets and real-time SpO₂ data compared with using only numerical oximeter values.

STUDY DESIGN

Preterm neonates were enrolled in this prospective cohort evaluation of a change in practice. The Transitional Oxygen Targeting System (TOTS) plots real-time SpO₂ values in relation to 10th and 50th percentile SpO₂ curves, which provides a visual target. After introduction of the TOTS, the resuscitation team adjusted the fraction of inspired oxygen to maintain the SpO₂ within the target range, and before its use neonates were resuscitated in attempt to target normal transitional SpO₂ values without using the TOTS monitor. Duration of time within 10th-50th percentile values was compared between 2 cohorts, children evaluated with the TOTS and those not evaluated with the TOTS (controls).

RESULTS

A total of 40 infants were enrolled, including 20 prospectively evaluated with the TOTS and 20 controls. Mean gestational age, birth weight, total resuscitation time, duration of supplemental oxygen administration, changes in oxygen concentration, and respiratory support provided were similar in the 2 groups. The TOTS cohort spent 52% of time within the target range; the control cohort, 37% (P = .03).

CONCLUSION

SpO₂ values were maintained within a specified target range for significantly longer in preterm neonates resuscitated using the TOTS display compared with those resuscitated without TOTS.

Oxygen administration for the resuscitation of term and preterm infants

Oxygen has been widely used in neonatal resuscitation for about 300 years. In October 2010, the International Liaison Committee on Neonatal Resuscitation released new guidelines. Based on experimental studies and randomized clinical trials, the recommendations on evaluation and monitoring of oxygenation status and oxygen supplementation in the delivery room were revised in detail. They include: inaccuracy of oxygenation clinical assessment (colour), mandatory use of pulse oximeter, specific saturation targets and oxygen concentrations during positive pressure ventilation in preterm and term infants. In this review, we describe oxygen management in the delivery room in terms of clinical assessment, monitoring, treatment and the gap of knowledge.

Oxygen saturation of healthy term neonates during the first 30 minutes of life

BACKGROUND

The purpose of this study was to document the oxygen saturation (SpO(2) ), general physical signs and laboratory characteristics during the first 30 min of life.

METHODS

Forty healthy singleton full-term neonates delivered vaginally (n = 33) or by cesarean section (n = 7) were included in this prospective observational study. After delivery, the SpO(2) levels of the upper (right hand; 'preductal') and lower (dorsum of the right foot; 'postductal') extremities of the neonates lying on the servo-controlled radiant heater in the delivery room were measured simultaneously with oximeter probes (Oxiprobe BM-270) placed at 1, 5, 10, 15, 20, 25, and 30 min. The correlation between pre- and postductal SpO(2) level and different variables (vital signs, capillary refill time recorded at 1 and 15 min, cord pH and hemoglobin values, and Apgar scores at 1 and 5 min) was examined.

RESULTS

The 1 min pre- and postductal SpO(2) were 82.3 ± 7.34% and 79.08 ± 8.16% (P > 0.05), respectively. The preductal values at 5, 10, and 15 min were statistically higher than the postductal values (89.73 ± 6.01%, 93.43 ± 4.06%, and 94.53 ± 3.19% vs 85.53 ± 6.92%, 89.9 ± 4.91%, 92.83 ± 3.92%, respectively). SpO(2) was the same regardless of the mode of delivery. No correlations were found between pre- and postductal SpO(2) and other variables.

CONCLUSIONS

Oxygen saturation was not affected by mode of delivery, was independent of Apgar score, cord hemoglobin, cord pH, vital signs, and capillary refill time in the first few minutes of life, and did not reach 90% in the first 5 min of life in healthy full-term neonates.

Correlation of pulse oximetry and apgar scoring in the normal newborns

CONTEXT

Apgar score (AS) is routinely used for assessment of newborns immediately after birth. Within acceptable limits, low saturations at birth are normal in vigorous newborn babies. Various studies have questioned the reliability of AS.

AIMS

To detect whether AS is an accurate indicator of hypoxemia and to study the correlation of different components of AS with the arterial oxygenation saturation (SpO2) levels of normal newborns in the delivery room.

SETTINGS AND DESIGN

A prospective cross-sectional observational study on normal healthy neonates delivered vaginally in a tertiary level referral medical college.

MATERIALS AND METHODS

SpO2 levels were monitored continuously in the newborns with a pulse oximeter and serial recording of SpO2 levels was done at 5 min intervals starting at 1 min of life until 30 min after birth. Simultaneously, AS was recorded in these newborns at 1 and 5 min of life.

STATISTICAL ANALYSIS

Data was analyzed using the Mann-Whitney-U test.

RESULTS

AS at 1 and 5 min of life didn't correlate with the changes in SpO2 of newborns. In AS; though respiratory efforts and muscle tone were significantly correlated with SpO2 of the newborns, body color did not have significant correlation with simultaneously recorded SpO2.

CONCLUSIONS

A revised AS in which evaluation of color is replaced by pulse oximetry monitoring would prove to be a better tool for neonatal evaluation in the immediate postnatal period.

Relationship between oxygen saturation and umbilical cord pH immediately after birth

BACKGROUND

The aim of this study is to determine the relationship between oxygen saturation (SpO(2)) by pulse oximetry levels and umbilical cord arterial pH values in healthy newborns during the first 15 minutes of life.

METHODS

The study was performed with healthy term, appropriate-for-gestational-age newborn infants. The infants were divided in two groups: umbilical cord arterial blood pH value ≤7.19 (group 1) and >7.19 (group 2); SpO(2) levels during the first 15 minutes of life were compared between groups.

RESULTS

The study was completed with 129 infants (33 in group 1 and 96 in group 2). A significant correlation was found between first-measured preductal and postductal SpO(2) levels by pulse oximetry and umbilical cord arterial pH values ([r²:0.72(0.62 -0.79); p < 0.001] and [r²:0.32(0.25 - 0.54); p < 0.001], respectively). In group 1, infants had lower SpO(2) levels at both preductal and postductal measurements during the first 11 minutes of life and time to reach ≥90% SpO(2) level was longer compared with infants in group 2.

CONCLUSION

Determination of umbilical arterial blood pH values, in addition to clinical findings and oxygen saturation measurements, might be helpful in deciding the concentration of oxygen and whether or not to continue oxygen supplementation in the delivery room.

Neonatal resuscitation: foetal physiology and pathophysiological aspects

Although approximately 10% of all newborn infants receive some form of assistance after birth, only 1% of neonates require more advanced measures of life support. Because such situations cannot always be anticipated, paediatricians and neonatologists are frequently unavailable and resuscitation is delegated to the anaesthesiologist. The International Liaison Committee on Resuscitation, the European Resuscitation Council and the American Heart Association have recently updated the guidelines on neonatal resuscitation. The revised guidelines propose a simplified resuscitation algorithm that highlights the central role of respiratory support and promotes an increasing heart rate as the best indicator for effective ventilation. The most striking change in the new guidelines is the recommendation to start resuscitation in term infants with room air rather than 100% oxygen. Continuous pulse oximetry is recommended to monitor both heart rate and an appropriate increase in preductal oxygen saturation. Supplemental oxygen should only be used if, despite effective ventilation, the heart rate does not increase above 100  beats  min(-1), or if oxygenation as indicated by pulse oximetry, remains unacceptably low. This review will focus on foetal physiology and pathophysiological aspects of neonatal adaptation and, thus, attempt to provide a solid basis for understanding the new resuscitation guidelines.

Evidence for oxygen use in preterm infants

AIM

To review the evidence for optimal oxygen use in preterm infants.

RESULTS

Clinicians have embraced lower saturation targets to minimize retinopathy of prematurity (ROP). Large randomized trials now have shown that while such targets reduce ROP, neonatal mortality is increased significantly.

CONCLUSIONS

Preterm infants should be resuscitated with blended oxygen (30-90%) targeted to avoid hyperoxia. Later, saturation management remains uncertain. Until ongoing trials and follow-up are complete, it is prudent to avoid saturation of 85-89%.

Right-to-left shunting in the ductus arteriosus is induced readily by intense crying and rapid postural change in neonates with meconium-stained amniotic fluid

OBJECTIVE

To investigate postnatal changes in the direction of blood flow through the ductus arteriosus in neonates with meconium-stained amniotic fluid, we measured preductal and postductal oxygen saturation in normal neonates, neonates with meconium-stained amniotic fluid, and a neonate with persistent pulmonary hypertension of the newborn.

DESIGN

Prospective, observational case series report.

SETTING

A single, tertiary neonatal intensive care unit.

PATIENTS

Twelve normal neonates, seven neonates with meconium-stained amniotic fluid, and a neonate with persistent pulmonary hypertension of the newborn.

INTERVENTIONS

SpO2 is simultaneously monitored in the right upper and lower limbs after birth.

MEASUREMENTS AND MAIN RESULTS

Compared with normal neonates, three neonates with meconium-stained amniotic fluid required longer than +2 SD of the mean time for the postductal SpO2 to reach 90% and/or 95%. In a neonate with meconium-stained amniotic fluid, intense crying triggered frequent decreases to <70% in the postductal SpO2 from 25 mins after birth, while the preductal SpO2 remained at 95% or above. When the other newborn with meconium-stained amniotic fluid was held in the father's arms after 98 mins, the postductal SpO2 decreased rapidly to <80%, while the preductal SpO2 remained at 95%. Thus, 5% or greater difference between the preductal and postductal SpO2 was observed from 25 mins after birth until 120 mins in all neonates with meconium-stained amniotic fluid, whereas the difference disappeared after 25 mins in 12 normal neonates. In a neonate with persistent pulmonary hypertension of the newborn who required vigorous resuscitation, 5% or greater difference between the preductal and postductal SpO2 levels was observed until 6 hrs after birth.

CONCLUSIONS

Right-to-left shunting in the ductus arteriosus may be induced readily by intense crying and rapid postural change in infants with meconium-stained amniotic fluid. It is important to monitor SpO2 at both pre- and postductal regions until 120 mins after birth in neonates with meconium-stained amniotic fluid and to subject these infants to minimal manipulations.

Room-air versus oxygen administration for resuscitation of preterm infants: the ROAR study

OBJECTIVE

We conducted a blinded, prospective, randomized control trial to determine which oxygen-titration strategy was most effective at achieving and maintaining oxygen saturations of 85% to 92% during delivery-room resuscitation.

METHODS

Infants born at 32 weeks' gestation or less were resuscitated either with a static concentration of 100% oxygen (high-oxygen group) or using an oxygen-titration strategy starting from a concentration of 100% (moderate-oxygen group), or 21% oxygen (low-oxygen group). In the moderate- and low-oxygen groups, the oxygen concentration was adjusted by 20% every 15 seconds to reach a target oxygen saturation range of 85% to 92%. Treatment failure was defined as a heart rate slower than 100 beats per minute for longer than 30 seconds.

RESULTS

The moderate-oxygen group spent a greater proportion of time in the target oxygen saturation range (mean: 0.21 [95% confidence interval: 0.16-0.26]) than the high-oxygen group (mean: 0.11 [95% confidence interval: 0.09-0.14]). Infants in the low-oxygen group were 8 times more likely to meet the criteria for treatment failure than those in the high-oxygen group (24% vs 3%; P = .022). The 3 groups did not differ significantly in the time to reach the target oxygen saturation range.

CONCLUSIONS

Titrating from an initial oxygen concentration of 100% was more effective than giving a static concentration of 100% oxygen in maintaining preterm infants in a target oxygen saturation range. Initiating resuscitation with 21% oxygen resulted in a high treatment-failure rate.

Normal oxygen saturation trend in healthy term newborns within 30 minutes of birth

OBJECTIVE

To determine normal arterial oxygen saturation (SpO(2)) trend during first 30 min of life and to evaluate for difference in SpO(2) trends in healthy term newborns of normal vaginal delivery (NVD) and elective cesarean section (CS).

METHODS

This Prospective Cross-sectional Observational study was conducted in Department of Pediatrics and Obstetrics, Gandhi Medical College, Bhopal. Newborns born of NVD and elective CS in first 30 min of life, complying with the study criteria were included in the study. Soon after birth, newborns with Apgar score ≥ 7 were given routine care and pulse-oximeter probe was applied on wiped right hand continuously for 30 min. Readings were obtained at an interval of 5 min.

RESULTS

Among NVD, the mean SpO(2) at 1, 5, 10, 15, 20, 25 and 30 min were 64.26%, 76.23%, 86.05%, 90.78%, 91.41%, 91.73% and 93.48%, respectively. The mean SpO(2) for CS was 67.43%, 78.50%, 88.44%, 90.81%, 91.46%, 91.83% and 92.88%, respectively. There was no significant difference in the SpO(2) between NVD and CS [95% CI = 74.8612-94.8359 in NVD and 77.1231-94.6912 in CS] and the correlation between NVD and CS being significant [r = 0.997 at 0.01 level]. There exists a strong positive correlation between Apgar and SpO(2) [r = 0.995, significant at 0.01 level (1-tailed) in NVD and r = 0.980, significant at 0.01 level (2-tailed) in CS].

CONCLUSIONS

The study defines the normal SpO(2) in healthy term newborns of NVD and CS delivered newborns and also concludes that there is no significant difference in SpO(2) among NVD and CS.

Avoiding hyperoxemia during neonatal resuscitation: time to response of different SpO2 monitors

Aim

To assess the time to obtain reliable oxygen saturation readings by different pulse oximeters during neonatal resuscitation in the delivery room or NICU.

Methods

Prospective study comparing three different pulse oximeters: Masimo Radical-7 compared simultaneously with Ohmeda Biox 3700 or with Nellcor N395, in newborn infants who required resuscitation. Members of the research team placed the sensors for each of the pulse oximeters being compared simultaneously, one sensor on each foot of the same baby. Care provided routinely, without interference by the research team. The time elapsed until a reliable SpO2 was obtained was recorded using a digital chronometer. Statistical comparisons included chi-square and student's T-test.

Results

Thirty-two infants were enrolled; median gestational age 32 weeks. Seventeen paired measurements were made with the Radical-7 and Biox 3700; mean time to a stable reading was 20.2 ± 7 sec for the Radical-7 and 74.2 ± 12 sec for the Biox 3700 (p = 0.02). The Radical-7 and the N- 395 were paired on 15 infants; the times to obtain a stable reading were 20.9 ± 4 sec and 67.3 ± 12 sec, respectively (p = 0.03).

Conclusion

The time to a reliable reading obtained simultaneously in neonatal critical situations differs by the type of the pulse oximeter used, being significantly faster with Masimo Signal Extraction Technology. This may permit for better adjustments of inspired oxygen, aiding in the prevention of damage caused by unnecessary exposure to high or low oxygen.

Tailoring oxygen needs of extremely low birth weight infants in the delivery room

Fetal to neonatal transition poses an extraordinary challenge for the extremely low birth weight (ELBW) neonate. Indeed a significant number of ELBW neonates will need proactive resuscitation to achieve postnatal stabilization. Positive pressure ventilation and oxygenation are the most relevant interventions in the delivery room (DR). Oxygen needs during resuscitation still represent a conundrum for neonatologists. While hyperoxemia favors oxidative stress and subsequent organ injury, hypoxemia is associated with long-term neurodevelopmental impairment. It has been shown that ELBW neonates can be successfully resuscitated with lower concentrations of oxygen as had been done traditionally. Moreover, reducing oxygen load has resulted in achievement of arterial partial pressures of oxygen at admission closer to the physiologic range, less oxidative stress and less inflammation. The availability of reference ranges for arterial oxygen saturation (SpO(2)) for ELBW neonates in the first 10 min after birth has been an extraordinary step forward in our ability to individually titrate oxygen needs thus avoiding the risks of both hypo- and hyperoxemia. The optimal fraction of inspired oxygen (FiO(2)) to initiate resuscitation and the safest SpO(2) percentiles for ELBW neonates during the first minutes of life are still unknown and will need further research in the future. Until then, optimal ventilation at birth and individually tailoring FiO(2) according to the nomogram seem to be the most reasonable and safe approach.

Neonatal resuscitation for the preterm infant: evidence versus practice

In an effort to determine the actual conduct of neonatal resuscitation and the errors that may be occurring during this process, we developed a method of video recording neonatal resuscitations as an ongoing quality assurance project. We initiated video recordings of resuscitations using simple video recorders attached to an overhead warmer and reviewed the resultant tapes during biweekly quality improvement meetings. We also added the continuous recording of analog information such as heart rate, oximeter values, fraction of inspired oxygen and airway pressure. We subsequently developed a checklist that includes a preresuscitation briefing and a postresuscitation debriefing, all of which are reviewed at the same time as the video recording. We have examined the use of oxygen in the very preterm infant, the effectiveness of bag and mask ventilation, including the detection of airway obstruction during such ventilation, intubation in the delivery area and environment. In addition, we have trained our teams and leaders using Crew Resource Management and focused on improved communication. The availability of a dedicated room for resuscitation allows an increased ambient environment and the ability to provide a user-friendly setting similar to the neonatal intensive care unit to optimize performance. There are numerous opportunities for improving team and leader performance and outcomes following neonatal resuscitation. Further prospective studies are required to evaluate specific interventions.

Neonatal resuscitation: Current issues

The following guidelines are intended for practitioners responsible for resuscitating neonates. They apply primarily to neonates undergoing transition from intrauterine to extrauterine life. The updated guidelines on Neonatal Resuscitation have assimilated the latest evidence in neonatal resuscitation. Important changes with regard to the old guidelines and recommendations for daily practice are provided. Current controversial issues concerning neonatal resuscitation are reviewed and argued in the context of the ILCOR 2005 consensus.