Oxygenation In Preterm Infants Research Articles

The effectiveness of automated adjustment of inspired oxygen in preterm infants receiving respiratory support compared with manual: A systematic review and meta‐analysis

AbstractPreterm infants may need supplemental oxygen due to immature lungs. Regardless of the type of oxygen therapy used, bedside clinicians frequently adjust the FiO2 level. Automatic oxygen management is progressively developing as a viable alternative to these corrections. The purpose of this study is to compare the efficacy and safety of automated versus manual oxygen control in preterm infants receiving respiratory support. All the studies were searched from PubMed, Web of Science, Cochrane Library, Embase, CNKI, Wan Fang, VIP, and CBM on 7 May 2022. PICOS criteria were as follows: (P) participants were preterm infants receiving respiratory support; (I) intervention was automatic oxygen control; (C) comparator mode was manual oxygen control; (O) the primary outcome was the percentage of time within the target pulse oxygen saturation range; (S) randomized clinical trials. Sixteen studies were included in this meta‐analysis. The results showed that automated oxygen control can increase the percentage of time spent within the target SpO2 range while reducing the percentage of time spent above the target SpO2 range, the percentage time of hypoxemia, and manual FiO2 adjustments/hour. No significant difference was observed in the percentage of time spent below the target SpO2 range, incidence of bradycardia, and the mean SpO2 or mean FiO2 level. Automatic oxygen control can improve preterm infants' oxygen saturation, reduce periods of hypoxemia and the percentage of time spent above the target SpO2 range, and ease the workload of medical staff without affecting the mean FiO2 and mean SpO2 levels.

Permissive hypercapnia and oxygenation impairment in premature ventilated infants

AimIn permissive hypercapnia high levels of carbon dioxide (CO2) are tolerated in ventilated preterm infants to minimise lung injury, but hypercapnia could directly impair oxygenation. We aimed to quantify the association of elevated CO2 with oxygenation impairment in preterm infants by measuring the right-to-left shunt and the ventilation/perfusion (VA/Q) ratio. MethodsPre-existing datasets from preterm infants during the acute phase of respiratory distress syndrome or with evolving or established bronchopulmonary dysplasia were analysed. Non-invasive paired measurements of the fraction of inspired oxygen (FIO2) and transcutaneous oxygen saturation (SpO2) were used to calculate the degree of right-to-left shunt, right shift of the FIO2 versus SpO2 curve and the VA/Q. ResultsA total of 75 infants (43 male) with a median (IQR) gestational age of 26.4 (24.7–27.7) weeks were studied at 7 (2–31) days. Thirty-six infants (48 %) had an arterial partial pressure of CO2 (PaCO2) above 6 kPa. The PaCO2 was independently associated with the right shift of the curve [adjusted p < 0.001, unstandardised coefficient; 2.26, 95 % CI: 1.51–2.95] and the right-to-left shunt [adjusted p = 0.016, unstandardised coefficient; 1.86, 95 % CI: 0.36–3.36] after adjusting for confounders. An increase of the PaCO2 from 5 to 8 kPa, corresponded to a right shift of the curve of 20.2 kPa or a decrease in the VA/Q from 0.66 to 0.24. ConclusionsIncreased carbon dioxide levels were significantly associated with impaired oxygenation in preterm infants with respiratory distress syndrome or bronchopulmonary dysplasia.

Apnoea-triggered increase in fraction of inspired oxygen in preterm infants: a randomised cross-over study

ObjectivesTo investigate the impact of a pre-emptive apnoea triggered oxygen response on oxygen saturation (SpO2) targeting following central apnoea in preterm infants.DesignInterventional crossover study of a 12-hour period of automated...

Predictive Intelligent Control of Oxygenation in Preterm Infants: A Two-Center Feasibility Study

Introduction: Supplemental oxygen therapy is a mainstay of modern neonatal intensive care for preterm infants. However, both insufficient and excess oxygen delivery are associated with adverse outcomes. Automated or closed loop FiO2 control has been developed to keep SpO2 within a predefined target range more effectively. Methods: The aim of this study was to investigate the feasibility of closed loop FiO2 control by Predictive Intelligent Control of Oxygenation (PRICO) on the Fabian ventilator in maintaining SpO2 within a target range (88/89-95%) in preterm infants on different modes of invasive and noninvasive respiratory support. In two tertiary neonatal intensive care units, preterm infants with an FiO2 >0.21 were included and received an 8 h nonblinded treatment period of closed loop FiO2 control by PRICO, flanked by two 8 h control periods of routine manual control (RMC1 and RMC2). Results: 32 preterm infants were included (median gestational age 26 + 5 weeks [IQR 25 + 5–27 + 6], median birthweight 828 grams [IQR 704–930]). Six patients received invasive respiratory support, while 26 received noninvasive respiratory support (18 CPAP, 4 DuoPAP, and 4 nasal IMV). The time percentage within the SpO2 target range was increased with PRICO (74.4% [IQR 67.8–78.5]) compared to RMC1 (65.8% [IQR 51.1–77.8]; p = 0.011) and RMC2 (60.6% [IQR 56.2–66.6]; p < 0.001) with an estimated median difference of 6.0% (95% CI 1.2–11.5) and 9.8% (95% CI 6.0–13.0), respectively. Conclusion: In preterm infants on invasive and noninvasive respiratory supports, closed loop FiO2 control by PRICO compared to RMC is feasible and superior in maintaining SpO2 within target ranges.

Splanchnic oxygenation during phototherapy in preterm infants with hyperbilirubinemia

BackgroundIt has been reported that preterm infants can develop feeding intolerance during phototherapy (PT) and that PT can affect mesenteric perfusion in these patients. AimsOur aim was to assess if PT can decrease regional splanchnic oxygenation (rSO2S) measured by near infrared spectroscopy (NIRS). Study designWe prospectively studied infants with gestational age of 25–34 weeks with hyperbilirubinemia requiring PT. Splanchnic regional oxygenation (rSO2S), oxygen extraction fraction (FOES), and cerebrosplanchnic oxygenation ratio (CSOR) were recorded before, during, and after PT discontinuation. ResultsDuring PT rSO2S and CSOR significantly decreased and this effect lasted for some hours after its interruption. FOES contemporary increased, although this effect was not statistically significant. ConclusionsPT treatment decreases splanchnic oxygenation in preterm infants likely due to peripheral vasodilation which triggers a redistribution of blood flow. These results can help explain the association between PT and the development of feeding intolerance in preterm infants.

A phase-II clinical trial of targeted cerebral near infrared spectroscopy using standardized treatment guidelines to improve brain oxygenation in preterm infants (BOx-II): A study protocol

BackgroundMortality and brain injury are common adverse outcomes in infants born <28 weeks. Conventional pulse oximetry may not detect subclinical changes prior to deterioration and fails to detect changes within the brain. Increasing evidence supports the use of cerebral near-infrared spectroscopy (NIRS) in the early care of preterm infants, yet the impact of specific interventions on cerebral oxygenation and the relationship between cerebral hypoxia and brain injury on MRI remain to be determined. Methods/design100 infants <28 completed weeks of gestation will be recruited for a prospective, multicenter intervention trial. After informed consent, infants will undergo cerebral NIRS monitoring starting within 6 h of birth and continuing through 72 h. Infants with persistent cerebral desaturation will receive interventions following a standard treatment algorithm selected by the provider based on the patient's clinical condition. Providers will record the timing and choice of intervention(s) and term equivalent brain MRI will be performed for survivors. There are three objectives of this study: 1) to identify the relationship between cerebral hypoxia burden and brain injury on term-equivalent MRI. 2) to identify most common interventions after cerebral hypoxia, and 3) to quantify frequency of occult cerebral hypoxia events. DiscussionThere is increasing evidence for the role of early cerebral NIRS monitoring in the neuroprotective care of preterm infants. This phase-II trial will provide essential data to improve the intervention approach, model the effect size of interventions on a wider extent of brain injury, and quantify the discrepancy between measurements of systemic and cerebral hypoxia.

Effects of Freshly Irradiated vs Irradiated and Stored Red Blood Cell Transfusion on Cerebral Oxygenation in Preterm Infants

Gamma irradiation of leukoreduced red blood cells (RBCs) prevents transfusion-associated graft-vs-host disease but also exacerbates storage lesion formation in RBCs. It is unknown whether freshly irradiated RBCs are more efficacious than irradiated and stored RBCs in preterm infants with high transfusion requirements. To examine whether transfusion of freshly irradiated vs irradiated and stored RBC components improves cerebral oxygen delivery in preterm infants with anemia. This single-center, double-blinded, proof-of-concept randomized clinical trial was conducted at the neonatal intensive care unit of Wellington Regional Hospital in Wellington, New Zealand, between December 1, 2017, and November 30, 2018. Participants were preterm infants (<34 weeks' gestation at birth) who were at least 14 days of age and had anemia. Participants underwent nonurgent transfusions, and these episodes were randomized to the intervention group (in which the infants received a transfusion of RBCs that were freshly irradiated on the day of transfusion) or control group (in which the infants received a transfusion of RBCs that were irradiated and stored for up to 14 days). Data were analyzed using the evaluable population approach. Transfusion of freshly irradiated RBCs. The prespecified primary outcome was the change in cerebral regional oxygen saturation (crSO2) from baseline (immediately before) to immediately after the transfusion. The prespecified secondary outcomes were the change in cerebral fractional tissue oxygen extraction (cFTOE) at different time points (immediately after, 24 hours after, and 120 hours or 5 days after transfusion). Outcomes were measured by blinded clinicians using near-infrared spectroscopy. A covariate-adjusted linear mixed model was used to quantify mean treatment effects and account for multiple transfusions in some infants. A total of 42 infants (mean [SD] gestational age, 26 [10] weeks and 3 days; 29 [69%] boys) were enrolled in the trial and underwent 64 transfusion episodes, which were randomized to the intervention (n = 31) or control (n = 33) group. Compared with infants in the control group, those in the intervention group showed a covariate-adjusted mean increase in crSO2 (2.0 percentage points; 95% CI, 1.2-2.8 percentage points) and a mean decrease in cFTOE (0.02; 95% CI, 0.01-0.04) immediately after transfusion. These differences were sustained up to 120 hours or 5 days after transfusion. There were negligible mean changes in crSO2 or cFTOE in infants in the control group at any of the follow-up time points. Results of this trial showed that transfusion of freshly irradiated RBCs conferred a small advantage in cerebral oxygenation for at least 5 days after transfusion compared with transfusion of irradiated and stored RBC components. On-demand irradiation of RBC components may be considered to optimize oxygen delivery in the recipient, but this physiological finding requires further research. ANZCTR Identifier: ACTRN12617001581358.

The effect of head positioning on brain tissue oxygenation in preterm infants: a randomized clinical trial study.

CNS injury in preterm infants is still one of the leading causes of mortality and morbidity. Routine care events might affect the perfusion and cerebral oxygenation of preterm infants. Although positioning the infant's head in a particular condition to improve brain oxygenation is included in many institutions, there is no robust clinical evidence to support this intervention's effectiveness. The present study aimed to determine the effect of head positioning on brain tissue oxygenation in preterm infants. This study is a randomized clinical trial. In the first 48 h after birth, 39 infants who met the study inclusion criteria underwent head positioning intervention. In this case, the infants were placed in the supine position, and every 2 h, the head position was changed continuously to one of six randomized modes [using random modes generated by SPSS]. During each head positioning, brain tissue oxygenation was recorded by NIRS. The findings showed a significant difference in brain tissue oxygen saturation among these positions (P < 0.001). Dunn's test showed that the brain tissue oxygen saturation in the third position (head rotates 45-60 degrees from the midline to the right and the head of the bed is zero degrees) was significantly lower than the baseline (P = 0.029; Mean difference = 2.3). Also, in the third position, compared to the first position (P = 0.002; Mean difference = 1.9) and compared to the fourth position (P = 0.003; Mean difference = -2.1), and in the second position compared to the first position (P = 0.046; Mean difference = 1.3), the brain tissue oxygen saturation of the infants was lower. Based on the results of the present study, head positioning was effective on brain tissue oxygenation in preterm infants in the first 48 h after birth; Therefore, it is recommended when possible, not to rotate the infant's head during the first 48 h after birth while the head of the bed is at 0°.

The Impact of Dexmedetomidine Initiation on Cardiovascular Status and Oxygenation in Critically ill Neonates.

Dexmedetomidine is being increasingly used as a primary or adjunctive sedative agent in neonates. There are a paucity of high-quality, high-resolution physiologic data during administration, despite significant potential cardiorespiratory effects. Term and preterm infants admitted between January 2018 and July 2020 were screened for dexmedetomidine exposure. Prospectively recorded vital signs (heart rate, oxygenation, arterial blood pressure) were cross-matched with pharmacy records to identify infants with data available 24h before and 48h after drug initiation. Vital sign data were processed via astandardized pipeline to (a) remove missing data, (b) obtain baseline averages of vital signs for 24h preceding dexmedetomidine, and (c) calculate the hourly mean deviation from the baseline for the 48h following initiation ofdexmedetomidine. Infants were clustered by postmenstrual age (preterm ≤ 35weeks; term > 35weeks). 72 infants were identified with mean gestational age of 32weeks and mean ± SD birth weight of 1976 ± 1341g. Although both groups of infants experienced bradycardia, heart rate in term infants dropped faster and reached a nadir 5 beats per minute lower, before converging at a common deviation of - 10 beats per minute. No hypo- or hypertension was noted in either group. Unexpected instability of oxygenation occurred in a subset of preterm infants, requiring escalation of respiratory support. Administration of dexmedetomidine results in differential timing and magnitude of bradycardia in term and preterm infants, no major impact on blood pressure, and a surprising instability of oxygenation in preterm infants, requiring increased ventilatory support. Further investigation is warranted.

Early Skin-to-Skin Contact Does Not Affect Cerebral Tissue Oxygenation in Preterm Infants

Aim: It was the aim of our study to determine the regional cerebral tissue oxygenation saturation (rcSO2) as an additional monitoring parameter during early skin-to-skin contact (SSC) in preterm infants with a gestational age of <32 gestational weeks. Methods: We conducted two observational convenience sample studies using additional monitoring with near-infrared spectroscopy (NIRS) in the first 120 h of life: (a) NIRS 1 (gestational age of 26 0/7 to 31 6/7 weeks) and (b) NIRS 2 (gestational age of 24 0/7 to 28 6/7 weeks). The rcSO2 values were compared between resting time in the incubator (period I), SSC (period II) and handling nursing care (period III). For the comparison, we separated the sequential effects by including a “wash-out phase” of 1 h between each period. Results: During the first 120 h of life 38/53 infants in NIRS 1 and 15/23 infants in NIRS 2 received SSC, respectively. We found no remarkable differences for rcSO2 values of NIRS 1 patients between SSC time and period I (95% confidence interval (CI) for the difference in %: SSC vs. period I [1; 3]). In NIRS 2, rcSO2 values during SSC were only 2% lower compared with period I [median [1. quartile; 3. quartile] in %; 78 [73; 82] vs. 80 [74; 85]] but were similar to period III [78 [72; 83]]. In a combined analysis, a small difference in rcSO2 values between SSC and resting times was found using a generalized linear mixed model that included gender and gestational age (OR 95% CI; 1.178 [1.103; 1.253], p < 0.0001). Episodes below the cut-off for “hypoxia”; e.g., <55%, were comparable during SSC and periods I and III (0.3–2.1%). No FiO2 adjustment was required in the vast majority of SSC episodes. Conclusions: Our observational data indicate that rcSO2 values of infants during SSC were comparable to rcSO2 values during incubator care and resting time. This additional monitoring supports a safe implementation of early SSC in extremely preterm infants in NICUs.

Neonatal anemia relates to intestinal injury in preterm infants.

BackgroundAnemia is associated with decreased tissue oxygenation in preterm infants and may contribute to developing necrotizing enterocolitis (NEC). We aimed to investigate whether hemoglobin level is associated with intestinal injury, by comparing anemic infants 10 days prior to red blood cell (RBC) transfusion with non-anemic controls.MethodsA nested case–control study in which we matched anemic preterms (gestational age (GA) < 32 weeks) with non-anemic controls (1:1), based on GA, birth weight (BW), and postnatal age. We measured urinary intestinal fatty acid-binding protein, I-FABP, marker for intestinal injury, twice weekly. Simultaneously, we assessed splanchnic oxygen saturation (rsSO2) and rsSO2 variability.ResultsThirty-six cases and 36 controls were included (median GA 27.6 weeks, BW 1020 grams). Median I-FABP level was higher in cases from 6 days to 24-h before transfusion (median ranging: 4749–8064 pg/ml versus 2194–3751 pg/ml). RsSO2 and rsSO2 variability were lower in cases than controls shortly before transfusion. Hemoglobin levels correlated negatively with rsSO2 and rsSO2 variability in cases, and negatively with I-FABP in cases and controls together.ConclusionsUrinary I-FABP levels were higher in anemic infants before RBC transfusion than in non-anemic matched controls, suggesting intestinal injury associated with anemia. This may predispose to NEC in some anemic preterm infants.Impact Anemia is a common comorbidity in preterm infants and may lead to impaired splanchnic oxygen saturation and intestinal tissue hypoxia, a proposed mechanism for NEC.Lower hemoglobin level is associated with higher urinary I-FABP levels, a marker for intestinal injury, both in anemic preterm infants and in cases and controls together.Lower splanchnic oxygen saturation and reduction of its variability are associated with higher urinary I-FABP levels in anemic preterm infants before their first RBC transfusion.These results support the hypothesis that anemia in very preterm infants results in intestinal cell injury, which may precede NEC development in some.

Precision of time-resolved near-infrared spectroscopy-based measurements of cerebral oxygenation in preterm infants.

.Significance: Time-resolved near-infrared spectroscopy (t-NIRS) is a new technology; at the moment, data on its precision in preterm infants are rare.Aim: Therefore, the aim of this study was to analyze the precision of t-NIRS-based measurements of the cerebral oxygenation in preterm infants.Approach: In 70 neonates [age: days, sex (f/m): 33/37], cerebral oxygenation () was measured with an optode placed over the left frontotemporal lobe on the head, measurement duration was 1 min, and a reapplication was done for four further times (five applications).Results: Overall mean for values was . We found a within-patient variation for of 2.6%. Furthermore, 95% of all observed values were within a range of from the mean when looking on several reapplications and when looking within one application. Most of the variation in (60.4%) contributed to differences between patients. The remaining 39.6% of the variation was due to measurement errors and real changes of the measured signal within the neonates.Conclusions: Since within-patient variation of measures were below a clinical meaningful threshold of 5%, the measurement can be denoted as precise.

Effects of fetal haemoglobin on systemic oxygenation in preterm infants and the development of retinopathy of prematurity PacIFiHER Report No. 2

Background/aimsFetal haemoglobin (HbF) has an oxyhaemoglobin dissociation curve that may affect systemic oxygenation and the development of retinopathy of prematurity (ROP). The study aim is to characterise the effects of...

Titration of inspired oxygen in preterm infants with hypoxemic respiratory failure using near-infrared spectroscopy and pulse oximetry: A new approach.

Titration of inspired oxygen is a challenge in preterm infants with hypoxemic respiratory failure (HRF). Monitoring of brain oxygen by near-infrared spectroscopy (NIRS) has been proven to minimize the burden of hyperoxia and hypoxemia; with a better understanding of cerebral autoregulation, integrating NIRS and pulse oximetry for titrating inspired oxygen in preterm infants is a novel approach. We studied the impact of integrated monitoring of oxygen saturation by pulse oximetry (SpO2 ) and cerebral regional tissue oxygen (crRTO) by NIRS during a stepwise oxygen reduction test (ORT) on reducing oxygen requirement in preterm infants with HRF. The correlation between SpO2 with crRTO, and fractional oxygen extraction (FOE) was assessed, concordance levels (r > 0.5) were determined during the assessment period and were considered as a sign of impaired autoregulation. The primary outcome was the achievement of significantly lower FiO2 at 72 h after the start of the integrated monitoring. A total of 38 preterm infants were included, 27 had normal cerebral autoregulation (CAR)(Group 1) in whom SpO2 was poorly correlating with crRTOwith (r < 0.5) and had a significantly greater percentage of reduction below baseline in FiO2 (mean: 34%). Eleven infants had impaired CAR (Group 2) with SpO2 significantly correlating with crRTO (r > 0.5) and had a linear trend of FOE inverse to SpO2 and crRTO; this was considered as an arterial saturation dependent oxygen delivery (SadDO2 ). Integrated monitoring of preterm infants by SpO2 and crRTO was associated with easier weaning of oxygen with less burden of both hyperoxia and hypoxemia.

Value of near-infrared spectroscopy in monitoring intestinal tissue oxygen saturation in preterm infants with hemodynamically significant patent ductus arteriosus: a prospective research.

To study the change in regional oxygen saturation (rSO2) of intestinal tissue in preterm infants with hemodynamically significant patent ductus arteriosus (hsPDA) by near-infrared spectroscopy, and the clinical significance of the change in intestinal oxygen level in preterm infants with hsPDA. The preterm infants with patent ductus arteriosus (PDA) who had gestational age <32 weeks and/or birth weight <1 500 g were prospectively enrolled, who were admitted to the Department of Neonatology, Shenzhen Longgang Central Hospital from October 2017 to October 2020.According to the diagnostic criteria for hsPDA, the preterm infants with patent ductus arteriosus (PDA) were divided into two groups: hsPDA and non-hsPDA. According to closure of the ductus arteriosus after oral administration of ibuprofen, the preterm infants in the hsPDA group were subdivided into two groups: hsPDA closure and hsPDA non-closure. Hemodynamic parameters were measured at diagnosis of PDA and after treatment, and the level of intestinal tissue rSO2 was monitored continuously to analyze its change. A total of 241 preterm infants with PDA were enrolled, with 55 infants (22.8%) in the hsPDA group and 186 infants (77.2%) in the non-hsPDA group. There were 36 infants (65%) in the hsPDA closure group and 19 infants (35%) in the hsPDA non-closure group. Compared with the non-hsPDA group, the hsPDA group had a significantly higher left atrial diameter/aortic root diameter ratio and significantly lower left ventricular ejection fraction and fractional shortening (P<0.05). At each time point within 6 hours after diagnosis (1, 2, 4, and 6 hours), the hsPDA group had significantly lower intestinal tissue rSO2 than the non-hsPDA group (P<0.05), and intestinal tissue rSO2 gradually decreased over time in the hsPDA group (P<0.05), with the lowest level of 0.448±0.014 at 6 hours. Compared with the hsPDA non-closure group, the hsPDA closure group had a significantly lower left atrial diameter/aortic root diameter ratio and significantly higher left ventricular ejection fraction and fractional shortening (P<0.05). At each time point within 48-96 hours after treatment (48, 72, and 96 hours), the hsPDA closure group had significantly higher intestinal tissue rSO2 than the hsPDA non-closure group (P<0.05), and intestinal tissue rSO2 gradually increased since 24 hours after treatment in the hsPDA closure group (P<0.05), with the highest level of 0.578±0.031 at 96 hours. hsPDA has an impact on intestinal tissue oxygenation in preterm infants, and continuous monitoring of intestinal tissue rSO2 by near-infrared spectroscopy can help to guide the clinical management of hsPDA in preterm infants.

Comparison of volume guarantee and volume-controlled ventilation both using closed loop inspired oxygen in preterm infants: a randomised crossover study (CLIO-VG study)

ObjectiveThe objective of this study was to compare two different modes of ventilation in maintaining oxygen saturation (SpO2) in target range (90%–95%) in ventilated preterm infants cared for with automatic...

Effects of Kangaroo Mother Care on Repeated Procedural Pain and Cerebral Oxygenation in Preterm Infants.

The study aimed to investigate the effects of kangaroo mother care (KMC) on repeated procedural pain and cerebral oxygenation in preterm infants. Preterm infants of 31 to 33 weeks of gestational age were randomly divided into an intervention group (n = 36) and a control group (n = 37). Premature infant pain profile (PIPP) scores, heart rate, oxygen saturation, regional cerebral tissue oxygenation saturation (rcSO2), and cerebral fractional tissue oxygen extraction (cFTOE) were evaluated during repeated heel stick procedures. Each heel stick procedure included three phases: baseline, blood collection, and recovery. KMC was given to the intervention group 30 minutes before baseline until the end of the recovery phase. Compared with the control group, the intervention group showed lower PIPP scores and heart rates, higher oxygen saturation, and rcSO2 from the blood collection to recovery phases during repeated heel sticks. Moreover, there were significant changes in cFTOE for the control group, but not the intervention group associated with repeated heel stick procedures. The analgesic effect of KMC is sustained over repeated painful procedures in preterm infants, and it is conducive to stabilizing cerebral oxygenation, which may protect the development of brain function. · KMC stabilizes cerebral oxygenation during repeated heel sticks in preterm infants.. · The analgesic effect of KMC is sustained over repeated painful procedures in preterm infants.. · KMC may protect the development of brain function..

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.