Oxygenation In Preterm Infants Research Articles

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

Aim of the studyAnalysis 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. MethodsThe 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). ResultsIn 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). ConclusionOur 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.

Inhaled Nitric Oxide at Birth Reduces Pulmonary Vascular Resistance and Improves Oxygenation in Preterm Lambs.

Resuscitation with 21% O2 may not achieve target oxygenation in preterm infants and in neonates with persistent pulmonary hypertension of the newborn (PPHN). Inhaled nitric oxide (iNO) at birth can reduce pulmonary vascular resistance (PVR) and improve PaO2. We studied the effect of iNO on oxygenation and changes in PVR in preterm lambs with and without PPHN during resuscitation and stabilization at birth. Preterm lambs with and without PPHN (induced by antenatal ductal ligation) were delivered at 134 d gestation (term is 147–150 d). Lambs without PPHN were ventilated with 21% O2, titrated O2 to maintain target oxygenation or 21% O2 + iNO (20 ppm) at birth for 30 min. Preterm lambs with PPHN were ventilated with 50% O2, titrated O2 or 50% O2 + iNO. Resuscitation with 21% O2 in preterm lambs and 50%O2 in PPHN lambs did not achieve target oxygenation. Inhaled NO significantly decreased PVR in all lambs and increased PaO2 in preterm lambs ventilated with 21% O2 similar to that achieved by titrated O2 (41 ± 9% at 30 min). Inhaled NO increased PaO2 to 45 ± 13, 45 ± 20 and 76 ± 11 mmHg with 50% O2, titrated O2 up to 100% and 50% O2 + iNO, respectively, in PPHN lambs. We concluded that iNO at birth reduces PVR and FiO2 required to achieve target PaO2.

A comparison of the effect of bi-level positive airway pressure and synchronized intermittent mandatory ventilation in preterm infants with respiratory distress syndrome

Objective Bi-level positive airway pressure (BiPAP) and synchronized intermittent mandatory ventilation (SIMV) can be used to achieve peak inspiratory pressure and positive end-expiratory pressure to avoid alveolar collapse and improve oxygenation in preterm infants during the treatment of respiratory distress syndrome (RDS), and there is an urgent demand for evaluating the effects and prognoses of these two ventilation modes. Study design We conducted a retrospective study on preterm infants (≤32 weeks and <2500 g) from March 2015 to March 2020 with BiPAP (n = 63) and SIMV (n = 63). The primary outcomes were successful treatment and weaning within 72 h, the demand for a second pulmonary surfactant supply and the need for a second respiratory support. The secondary outcome was the incidence of complications. Results There were no significant differences (p > .05) in the primary outcomes or the incidence of complications (pneumonia, apnea, respiratory failure, air leak syndrome, persistence of patent ductus arteriosus, neonatal sepsis, necrotizing enterocolitis, retinopathy of prematurity, and intraventricular hemorrhage). There were significant differences (p < .05) in the incidence of pulmonary hemorrhage, bronchopulmonary dysplasia and IVH (≥grade II). Conclusions Although both BiPAP and SIMV achieved good early treatment outcomes of RDS in preterm infants, BiPAP support is recommended for reducing the incidence of pulmonary hemorrhage, bronchopulmonary dysplasia and IVH (≥grade II) if infants are tolerant. Attempts should be made to prevent these complications from happening with the use of SIMV support if infants are intolerant.

The utility of cerebral oxygenation monitoring in premature neonates

Near-infrared spectroscopy allows the measurement of cerebral oxygenation in preterm infants. This study aimed to demonstrate several highly relevant clinical situations in preterm infants in which the standard set of monitoring parameters without near-infrared spectroscopy is not sufficient to detect possible adverse situations, possibly resulting in severe complications, i.e. adverse neurological outcomes. The examples include situations of low blood pressure, persistent open ductus arteriosus, malfunctioning autoregulation of the brain oxygenation, and periods of irregular breathing. Without near-infrared spectroscopy, it is impossible to determine whether such a situation imposes any risk for the brain, whereas the measurement of cerebral oxygenation as an additional source of information enables the clinician to recognise these conditions and modify treatment or use countermeasures to protect the patient from brain damage and ensuing lifelong disabilities.

Cerebral oxygenation in preterm infants during maternal singing combined with skin-to-skin care.

Our aim was to investigate the effect of music therapy in combination with skin-to-skin care (SSC) on regional cerebral oxygenation (rSO2) measured with near-infrared spectroscopy (NIRS) in premature infants and to study physiological stability during the interventions. This was a prospective single-center observational cohort study conducted in a tertiary neonatal intensive care unit. The study consisted of four phases: (1) baseline measurements in an incubator for 30 min; (2) quiet SSC for 30 min (SSC-Pre); (3) SSC with live maternal singing accompanied by live guitar music for 20 min (SSC-Music); (4) final quiet SSC for another 30 min (SSC-Post). The primary outcome measure of mean rSO2 for the 31 preterm infants analyzed showed a significant increase from baseline during SSC-Music (76.87% vs 77.74%, p = 0.04) and SSC-Post (76.87% vs 78.0%, p = 0.03) phases. There were no significant changes observed in heart rate (HR), peripheral oxygen saturation (SpO2), and cerebral fractional tissue oxygen extraction (cFTOE). The coefficient of variation (CV) of rSO2 and SpO2 decreased during each intervention phase. Combining music therapy with SSC appears to be safe in preterm neonates. The impact of the small increase in rSO2 and reduced variability of SpO2 and rSO2 warrants further investigation. Music therapy combined with skin-to-skin care (SSC) is safe in clinically stable premature infants and could be encouraged as part of developmental care. This is the first report where near-infrared spectroscopy (NIRS) was used to detect the simultaneous effect of music therapy and SSC on cerebral rSO2 in preterm infants. Music therapy with SSC caused a modest increase in rSO2 and decreased the coefficient of variation of rSO2 and peripheral oxygen saturation (SpO2), which suggest short-term benefits for preterm infants.

Cerebral Oxygenation in Preterm Infants With Necrotizing Enterocolitis

Preterm infants with necrotizing enterocolitis (NEC) are known to have worse neurodevelopmental outcomes, but there is no substantial evidence to support an underlying pathophysiology. We aimed to examine whether cerebral oxygenation differs in those infants who develop NEC compared to cerebral oxygenation in those who do not. We examined 48 infants <30 weeks' gestation admitted to a tertiary level NICU from October 2016 to May 2018. Infants with birth weight less than or equal to the second percentile, abnormal antenatal dopplers or twin-to-twin-transfusion-syndrome were excluded. Cerebral oximetry measurements were performed by using a near-infrared spectroscopy (NIRS) monitor weekly for 60 minutes, allowing measurement of cerebral tissue oxygenation index from the first week of life to 36 weeks postconceptional age. Weekly clinical status was also recorded. NEC was defined as greater than or equal to Bell stage 2. The median birth weight was 884 g (range of 460-1600 g), the median weeks' gestational age was 26 + 3/7 (23 + 0/7 to 29 + 6/7), and 52% were girls. In total, 276 NIRS measurements were completed, and 7 infants developed NEC. NIRS measurements from 1 infant with NEC and 4 infants without NEC who developed hemorrhagic parenchymal infarcts were excluded from analysis. Infants who developed NEC had significantly lower cerebral tissue oxygenation index than those who did not (P = .011), even when adjusted for confounders, including gestational age, birth weight, patent ductus arteriosus, enteral feeds, sex, ethnicity, and hemoglobin. Infants with NEC have significantly lower cerebral tissue oxygenation throughout their neonatal intensive care stay in comparison with those who did not develop NEC. This is a novel finding and could explain their worse neurodevelopmental outcome.

FEEding DURing red cell transfusion (FEEDUR RCT): a multi-arm randomised controlled trial

BackgroundNecrotising Enterocolitis (NEC) is a devastating neonatal disease. A temporal association between red cell transfusion and NEC has been recognized and there have been concerns about the effects of feeding during transfusion. We aimed to assess the effect of different enteral feeding regimens on splanchnic oxygenation in preterm infants receiving red cell transfusions.MethodsThis was an open, multi-arm, parallel-group, randomised controlled trial conducted in a single centre in Australia. We compared three different enteral feeding regimes during a single red cell transfusion in preterm infants < 35 weeks gestational age at birth. Infants were randomised to either: (1) Withholding enteral feeds for 12 h from the start of transfusion or; (2) Continuing enteral feeds or; (3) Restriction of enteral feed volume to 120 ml/kg/day (maximum 20 kcal/30 ml) for 12 h. The primary outcome was mean splanchnic-cerebral oxygenation ratio (SCOR) and mean splanchnic fractional oxygen extraction (FOE) before (1 h prior), during (1 h into transfusion) and after (end of transfusion; 12 and 24 h post) transfusion.ResultsThere were 60 transfusion episodes (20 transfusion episodes in each group) included in the analysis. 41 infants with a median gestational age at birth of 27 weeks (range 23–32 weeks) were enrolled. The median postnatal age was 43 days (range 19–94 days) and the median pre-transfusion haematocrit was 0.27 (range 0.22–0.32). All three groups were similar at baseline. There were no differences in mean SCOR and mean splanchnic FOE at any of the pre-specified time points. There were also no differences in clinical outcomes. There were no episodes of NEC in any infant. Across all groups the mean SCOR increased from the start to the end of each transfusion (0.97 [CI95% 0.96–0.98] vs 1.00 [CI95% 0.99–1.01]; p = 0.04) and the mean FOE decreased from the start to the end of each transfusion (0.22 [CI95% 0.21–0.23] vs 0.17 [CI95% 0.16–0.18]; p < 0.001).ConclusionsThere were no differences in splanchnic oxygenation when enteral feeds were either withheld, continued or restricted during a transfusion. However, the successful conduct of this study supports the feasibility of a large trial powered to assess clinical outcomes.Trial registrationANZCTR, ACTRN12616000160437. Registered 10 February 2016, https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=370069

Effects of Single Loading Dose of Intravenous Caffeine on Cerebral Oxygenation in Preterm Infants.

The aim of this study was to evaluate the effects of caffeine on cerebral oxygenation in preterm infants. This was a prospective study of infants with a gestational age (GA) of < 34 weeks who were treated intravenously with a loading dose of 20 mg/kg caffeine citrate within the first 48 hours of life. Regional cerebral oxygen saturation (rSO2C) and cerebral fractional tissue oxygen extraction (cFTOE) were measured using near-infrared spectroscopy before administering caffeine (baseline), immediately after administering caffeine, and 1, 2, 3, 4, 6, and 12 hours after dose completion; postdose values were compared with the baseline values. A total of 48 infants with a mean GA of 29.0 ± 1.9 weeks, birth weight of 1,286 ± 301 g, and postnatal age of 32.4 ± 11.3 hours were included in the study. rSO2C significantly decreased from 81.3 to 76.7% soon after administering caffeine, to 77.1% at 1 hour, and to 77.8% at 2 hours with recovery at 3 hours postdose. rSO2C was 80.2% at 12 hours postdose. cFTOE increased correspondingly. Although rSO2C values were lower and cFTOE values were higher compared with the baseline values at 3, 4, 6, and 12 hours after caffeine administration, this was not statistically significant. A loading dose of caffeine temporarily reduces cerebral oxygenation and increases cerebral tissue oxygen extraction in preterm infants. Most probably these changes reflect a physiological phenomenon without any clinical importance to the cerebral hemodynamics, as the reduction in cerebral oxygenation and increase in cerebral tissue oxygen extraction remain well within acceptable range.

This issue of acta

This issue of acta

Effects of Caffeine on Splanchnic Oxygenation in Preterm Infants

The aim of this study is to assess the effects of administering 20 mg/kg loading dose of caffeine citrate intravenously on splanchnic oxygenation in preterm infants. The infants with a gestational age (GA) of <34 weeks who were administered with a 20 mg/kg intravenous loading dose of caffeine citrate within 48 hours after birth were investigated prospectively. Regional splanchnic oxygen saturation (rsSO2) and splanchnic fractional tissue oxygen extraction rate (sFTOE) were measured using near-infrared spectroscopy before caffeine infusion, immediately after caffeine infusion and 1, 2, 3, 4, and 6 hours (h) after dose completion; postdose values were compared with predose values. A total of 41 infants with a mean GA of 29.2 ± 1.6 weeks and birth weight of 1,315 ± 257 g as well as postnatal age of 32.2 ± 10.8 hours were included in the study. rsSO2 significantly reduced from 63.1 to 57.5% immediately after caffeine infusion, 55.1% after 1 hour, and 55.2% after 2 hours with partial recovery at 3-hour postdose. sFTOE increased correspondingly. Caffeine reduces splanchnic oxygenation and increases splanchnic oxygen extraction for at least 2 hours with partial recovery to predose levels at 3-hour postdose.

The Effect of Continuous Positive Airway Pressure on Cerebral and Splanchnic Oxygenation in Preterm Infants

Background: Despite the known clinical benefits of continuous positive airway pressure (CPAP) to support preterm infants breathing, there are limited studies that have examined its effect on regional oxygenation. Objectives: This study aimed to investigate how the application of CPAP affects cerebral and splanchnic tissue oxygenation in preterm infants. Methods: A pilot observational study was conducted in infants using near-infrared spectroscopy while off CPAP and on CPAP. Regional cerebral and splanchnic saturations and variability (coefficient of variability; CV) were evaluated. Results: Twenty-six infants (25–37 weeks gestational age at birth) were studied. The mean cerebral oxygenation did not differ with the application of CPAP (80 ± 4.2% without CPAP; 80 ± 1.9% with CPAP), but variability around the mean was less with CPAP (CV 5 vs. 2%, respectively). Mean cerebral fractional oxygen extraction (FOE) increased with CPAP from 0.13 ± 0.06 to 0.17 ± 0.04% (p = 0.002). Splanchnic oxygenation increased significantly from 66 ± 11.6 to 75 ± 9.1% with CPAP (p < 0.001) and also became more stable (CV 13 vs. 7%, respectively). Splanchnic FOE decreased with CPAP from 0.28 ± 0.13 to 0.22 ± 0.10% (p = 0.002). Conclusion: The application of CPAP did not affect mean cerebral oxygenation in this group of preterm and term infants; however, it led to a significant increase in splanchnic oxygenation. These findings highlight the important role that respiratory support may play in maintaining adequate and stable oxygen delivery to vital organs.

The effect of less invasive surfactant administration on cerebral oxygenation in preterm infants.

To determine the regional cerebral tissue oxygenation saturation (rcSO2 ) in a group of infants requiring less invasive surfactant administration (LISA) as compared to infants with continuous positive airway pressure (CPAP) only. In preterm infants with a gestational age 26 0/7-31 6/7weeks, we conducted an observational study using near-infrared spectroscopy (NIRS) in the first 120hours of life. We analysed the data of 22 infants who never received surfactant (CPAP), 22 infants had LISA and CPAP (LISA) and 6 infants received surfactant via endotracheal tube (ETT). Four infants had both surfactant application modes including six LISA applications. In total, there were 32 successful LISA applications but 44 attempts; 13/44 (30%) of LISA attempts resulted in a 20% decrease of rcSO2 . During the first 120hours of life, rcSO2 values of CPAP were similar to those of infants in the LISA group, that is median rcSO2 values 90% vs 85%, respectively (P=.126). Episodes with rcSO2 values <65% were 0.4% in the CPAP group as compared to 4.8% in the LISA group (P<.001). Our observational data indicate that rcSO2 values of infants in the LISA group were similar to the CPAP group.

Clamping the Umbilical Cord in Premature Deliveries (CUPiD): Neuromonitoring in the Immediate Newborn Period in a Randomized, Controlled Trial of Preterm Infants Born at

To compare cerebral activity and oxygenation in preterm infants (<32weeks of gestation) randomized to different cord clamping strategies. Preterm infants born at <32weeks of gestation were randomized to immediate cord clamping, umbilical cord milking (cord stripped 3 times), or delayed cord clamping for 60seconds with bedside resuscitation. All infants underwent electroencephalogram (EEG) and cerebral near infrared spectroscopy for the first 72hours after birth. Neonatal primary outcome measures were quantitative measures of the EEG (17 features) and near infrared spectroscopy over 1-hour time frames at 6 and 12hours of life. Forty-five infants were recruited during the study period. Twelve infants (27%) were randomized to immediate cord clamping, 19 (42%) to umbilical cord milking, and 14 (31%) to delayed cord clamping with bedside resuscitation. There were no significant differences between groups for measures of EEG activity or cerebral near infrared spectroscopy. Three of the 45 infants (6.7%) were diagnosed with severe IVH (2 in the immediate cord clamping group, 1 in the umbilical cord milking group; P=.35). There were no differences in cerebral EEG activity and cerebral oxygenation values between cord management strategies at 6 and 12hours. ISRCTN92719670.

Cerebral oxygenation in preterm infants receiving transfusion.

The influence of severity of anemia and cardiac output (CO) on cerebral oxygenation (CrSO2) and on the change in CrSO2 following packed red blood cell (PRBC) transfusion in preterm infants has not been evaluated. The objectives of the current study were to evaluate the effect of pre-transfusion hemoglobin (Hb) and CO-weighted oxygen delivery index (ODI) on CrSO2 and on the post-transfusion CrSO2 change. Preterm infants of <32 weeks gestational age (GA) receiving PRBC transfusion were enrolled. Infants received 15 ml/kg PRBC over 3 h. CrSO2 by near-infrared spectroscopy and CO by electrical velocimetry were recorded for 1 h pre-ransfusion and post transfusion. ODI was defined as pre-transfusion Hb × CO. Thirty infants of 26.6 ± 2.0 weeks GA were studied at 19 ± 12 days. Pre-transfusion Hb was 9.8 ± 0.6 g/dl. Pre-transfusion CrSO2 correlated with pre-transfusion ODI (R2 = 0.1528, p = .044) but not with Hb level. The pre-transfusion to post-transfusion CrSO2 change correlated with pre-transfusion ODI (R2 = 0.1764, p = .029) but not with Hb level. CrSO2 increased from 66 ± 6% to 72 ± 7% post transfusion (p < .001), while arterial oxygen saturation, heart rate, and CO did not change. In these infants, the pre-transfusion ODI was a better indicator of brain oxygenation and its improvement post transfusion than Hb alone. The role of CO and tissue oxygenation monitoring in assessing the need for transfusion should be evaluated.

Low Cerebral Oxygenation in Preterm Infants Is Associated with Adverse Neurodevelopmental Outcome

To assess whether high and low levels of cerebral oxygenation (regional cerebral oxygenation [rScO2]) in infants born at <32 weeks of gestation were associated with adverse long-term outcome. Observational cohort study including preterm infants born at <32 weeks of gestation at the Wilhelmina Children's Hospital, The Netherlands, between April 2006 and April 2013. The rScO2 was continuously monitored for 72 hours after birth using near-infrared spectroscopy. Outcome was assessed at 15 and 24 months of corrected age by certified investigators. An unfavorable composite outcome was defined as an outcome score below -1 SD or death. Various rScO2 thresholds were explored. In total, 734 infants were eligible for analysis, 60 of whom died. Associations with an unfavorable cognitive outcome in multivariable analysis were comparable for time spent with a rScO2 below 55% and -1.5 SD (according to published reference values), with an OR of 1.4 (CI 1.1-1.7) for 20% of time below either threshold. Results at 15 months were comparable with results at 24 months. Results were not statistically significant for thresholds defining high values of rScO2. The composite motor outcome was not significantly related to either low or high values or rScO2. Low, but not high, rScO2 was associated with an unfavorable cognitive outcome. This suggests the use of a threshold of rScO2 <55% for future clinical studies when using adult near-infrared sensors (rScO2 <65% for neonatal sensors, approximately).

Effects of Prone Sleeping on Cerebral Oxygenation in Preterm Infants

To determine the effect of prone sleeping on cerebral oxygenation in preterm infants in the neonatal intensive care unit. Preterm infants, divided into extremely preterm (gestational age 24-28 weeks; n = 23) and very preterm (gestational age 29-34 weeks; n = 33) groups, were studied weekly until discharge in prone and supine positions during active and quiet sleep. Cerebral tissue oxygenation index (TOI) and arterial oxygen saturation (SaO2) were recorded. Cerebral fractional tissue extraction (CFOE) was calculated as CFOE = (SaO2 - TOI)/SaO2. In extremely preterm infants, CFOE increased modestly in the prone position in both sleep states at age 1 week, in no change in TOI despite higher SaO2. In contrast, the very preterm infants did not have position-related differences in CFOE until the fifth week of life. In the very preterm infants, TOI decreased and CFOE increased with active sleep compared with quiet sleep and with increasing postnatal age. At 1 week of age, prone sleeping increased CFOE in extremely preterm infants, suggesting reduced cerebral blood flow. Our findings reveal important physiological insights in clinically stable preterm infants. Further studies are needed to verify our findings in unstable preterm infants regarding the potential risk of cerebral injury in the prone sleeping position in early postnatal life.

Bradycardias are associated with more severe effects on cerebral oxygenation in very preterm infants than in late preterm infants

BackgroundCommonly the magnitude and frequency of bradycardia is underestimated in the neonatal unit due to the long averaging time used in bedside oximeters. We aimed to assess the frequency and severity of bradycardia in preterm infants using the lowest averaging time (2 s) available on a clinical oximeter, compared with bradycardia detected using electrocardiogram (ECG), and whether bradycardia severity and postmenstrual age affected cerebral oxygenation. MethodsPreterm infants (10 M/9F) were studied longitudinally at 26–31 (very preterm) and 32–38 weeks (late preterm) postmenstrual age. Heart rate falls calculated from ECG were used to determine mild or moderate/severe (MS) bradycardias. Cerebral tissue oxygenation index (TOI, %) was recorded and fractional tissue oxygen extraction (FTOE) calculated. ResultsOf the 615 bradycardias scored using ECG criteria, 10% were not detected by oximetry. TOI falls associated with bradycardias were greater for MS bradycardias compared with Mild for both groups (p < 0.001 for both). The FTOE associated with MS bradycardias was higher for the very preterm compared with the late preterm group (p < 0.001). In very preterm infants 61% of MS and 35% Mild bradycardias were associated with TOI nadirs below 55%. ConclusionEven the most sensitive oximeter setting underestimates bradycardias. The cerebral effect from bradycardias in very preterm infants is more severe than in late preterm infants. Even the mild bradycardias are associated with falls in cerebral oxygenation. Routine NIRS monitoring of cerebral oxygenation in NICUs may increase staff awareness for interventions to reduce the repetitive falls in cerebral oxygenation in preterm infants.

Statistical methods for characterizing transfusion-related changes in regional oxygenation using near-infrared spectroscopy (NIRS) in preterm infants.

Near infrared spectroscopy (NIRS) is an imaging-based diagnostic tool that provides non-invasive and continuous evaluation of regional tissue oxygenation in real-time. In recent years, NIRS has shown promise as a useful monitoring technology to help detect relative tissue ischemia that could lead to significant morbidity and mortality in preterm infants. However, some issues inherent in NIRS technology use on neonates, such as wide fluctuation in signals, signal dropout and low limit of detection of the device, pose challenges that may obscure reliable interpretation of the NIRS measurements using current methods of analysis. In this paper, we propose new nonparametric statistical methods to analyze mesenteric rSO2 (regional oxygenation) produced by NIRS to evaluate oxygenation in intestinal tissues and investigate oxygenation response to red blood cell transfusion (RBC) in preterm infants. Specifically, we present a mean area under the curve (MAUC) measure and a slope measure to capture the mean rSO2 level and temporal trajectory of rSO2, respectively. We develop estimation methods for the measures based on multiple imputation and spline smoothing and further propose novel nonparametric testing procedures to detect RBC-related changes in mesenteric oxygenation in preterm infants. Through simulation studies, we show that the proposed methods demonstrate improved accuracy in characterizing the mean level and changing pattern of mesenteric rSO2 and also increased statistical power in detecting RBC-related changes, as compared with standard approaches. We apply our methods to a NIRS study in preterm infants receiving RBC transfusion from Emory University to evaluate the pre- and post-transfusion mesenteric oxygenation in preterm infants.

Feed‐related Splanchnic Oxygenation in Preterm Infants With Abnormal Antenatal Doppler Developing Gut Complications

Preterm infants with antenatal absent or reversed end diastolic flow (AREDF) in umbilical arteries are at major risk for gastrointestinal (GI) complications, such as necrotizing enterocolitis, intestinal perforation and feeding intolerance. Near-infrared spectroscopy provides continuous monitoring of splanchnic oxygenation (SrSO2) and may represent a useful tool to predict GI outcomes in this high-risk population. This observational, pilot study assessed feed-related SrSO2 patterns at enteral feeding introduction and full enteral feeding (FEF) achievement in twenty AREDF infants with gestational age ≤34 weeks. Enrolled infants were divided into 2 groups according to the development versus lack of GI complications. Infants developing GI complications showed significantly lower SrSO2 and increased splanchnic oxygen extraction in response to enteral feeds at both enteral feeding introduction and FEF. The potential role of these findings in predicting GI complications in AREDF preterm infants seems promising and deserves further evaluation.

Applications of near infrared spectroscopy in the neonate.

There has been a significant increase in the utilization of NIRS in neonatal care over the last few years, with some centers now routinely utilizing this monitoring technique for direct intervention at the bedside. In this review, we provide a summary of the most up-to-date evidence on near infrared spectroscopy utilization, with particular emphasis on measurement of cerebral oxygenation in preterm infants. There have been significant advances in the technology, leading to an increase in the number of available devices and in the use of this monitoring tool to reduce cerebral injury in preterm infants. The role of NIRS in assessing cerebral autoregulation in preterm and term infants, in evaluating somatic oxygenation, and in the management of newborns with hypoxic ischaemic encephalopathy is discussed. Two recent pilot randomized controlled trials highlight the potential of cerebral oxygenation monitoring to direct management in the delivery room and the neonatal intensive care unit. However, we urge caution against routine use and await the results of further studies in this area before considering this type of monitoring as standard of care.