Evaluation of Oxygen Saturation Index Compared With Oxygenation Index in Neonates With Hypoxemic Respiratory Failure

Mortality in the neonatal intensive care setting: Do benchmarks tell the whole story?

AIM

Australian neonatal mortality data are collected and shared within collaborative networks. Individual unit outcomes are benchmarked between units and presented in quarterly or yearly reports. Low mortality is commonly interpreted as optimal performance. However, current collected data do not differentiate between death due to severe illness and death following treatment limitation. This study aims to explore the physiological condition immediately before death, and the proportion of deaths attributed to treatment limitation.

METHODS

This retrospective single centre study of 100 consecutive deaths classified the physiological condition 12 h prior to death as stable or unstable using a clinical illness score based upon pH, oxygen saturation index, medications and blood product use. Documented discussions regarding expected outcomes and goals of management were reviewed for agreed upon treatment limitations and analysed against physiological stability.

RESULTS

Causes of death were sepsis (n = 24), congenital anomalies (n = 20), extreme prematurity (n = 19), hypoxic ischaemic encephalopathy (n = 18), intraventricular haemorrhage (n = 11) and other (n = 8). Forty-eight infants were physiologically stable at 12 h before death. In infants classified as physiologically stable, 90% of deaths were in a scenario where palliative care was discussed and intensive care treatment was ceased. These deaths accounted for 43% of total mortality in our unit.

CONCLUSION

A large portion of mortality in our unit could be attributed to treatment limitations in physiologically stable infants with high risk of neurodevelopmental impairment. Our study emphasises the need to consider the physiological status around time of death for optimal benchmarking of mortality between neonatal units.

Etiology, Diagnosis and Management of Persistent Pulmonary Hypertension of the Newborn in Resource-limited Settings

Persistent Pulmonary Hypertension of the Newborn (PPHN) is more common in Low and middle income countries (LMICs) due to high incidence of sepsis, perinatal asphyxia and meconium aspiration syndrome. Presence of hypoxic respiratory faillure and greater than 5% difference in preductal and post ductal saturation increases clinical sucipision for PPHN. The availability of Inhaled nitric oxide and extracorporaeal membrane oxygenation is limited but pulmonary vasodilators such as sildenafil are readily available in most LMICs.

Impact of the first 24 h of continuous kidney replacement therapy on hemodynamics, ventilation, and analgo-sedation in critically ill children

BACKGROUND

In a group of children admitted to the paediatric intensive care unit (PICU) receiving continuous kidney replacement therapy (CKRT), we aim to evaluate the data about their hemodynamic, ventilation and analgo-sedation profile in the first 24 h of treatment and possible associations with mortality.

METHODS

Retrospective cohort study of children admitted to the PICU of the University Hospital of Padova undergoing CKRT between January 2011 and March 2021. Data was collected at baseline (T0), after 1 h (T1) and 24 h (T24) of CKRT treatment. The differences in outcome measures were compared between these time points, and between survivors and non-survivors.

RESULTS

Sixty-nine patients received CKRT, of whom 38 (55%) died during the PICU stay. Overall, the vasoactive inotropic score and the adrenaline dose increased at T1 compared to T0 (p = 0.012 and p = 0.022, respectively). Compared to T0, at T24 patients showed an improvement in the following ventilatory parameters: Oxygenation Index (p = 0.005), Oxygenation Saturation Index (p = 0.013) PaO2/FiO2 ratio (p = 0.005), SpO2/FiO2 ratio (p = 0.002) and Mean Airway Pressure (p = 0.016). These improvements remained significant in survivors (p = 0.01, p = 0.027, p = 0.01 and p = 0.015, respectively) but not in non-survivors. No changes in analgo-sedative drugs have been described.

CONCLUSIONS

CKRT showed a significant impact on hemodynamics and ventilation in the first 24 h of treatment. We observed a significant rise in the inotropic/vasoactive support required after 1 h of treatment in the overall population, and an improvement in the ventilation parameters at 24 h only in survivors.

Oxygen saturation index: an adjunct for oxygenation index in congenital diaphragmatic hernia

OBJECTIVE

Our objective was to investigate the correlation of Oxygen Saturation Index (OSI) with Oxygenation Index (OI) and determine OSImax values that could predict need for ECMO and death in Congenital Diaphragmatic Hernia (CDH).

STUDY DESIGN

This is a retrospective cohort study of infants with CDH admitted to a tertiary level VI NICU. Pearson's correlation coefficient and simple linear regression analysis were used to investigate the OSI: OI correlation, and logistic regression analysis to investigate OSImax values that predicted need for ECMO and death.

RESULTS

Among the 180 infants, OSImax value of >13 at 6 h of life (HOL) best predicted need for ECMO and death. There was a strong correlation between OSI: OI paired values (r = 0.876, p < 0.001). The linear regression equation was OI = -2.4 + 2.4(OSI).

CONCLUSION

OSI could be used as a valuable adjunct to OI in the clinical management of newborn infants with CDH.

Study protocol for a randomised cross-over trial of Neurally adjusted ventilatory Assist for Neonates with Congenital diaphragmatic hernias: the NAN-C study

BACKGROUND

Neurally adjusted ventilatory assist (NAVA) is a mode of mechanical ventilation that delivers oxygen pressures in proportion to electrical signals of the diaphragm. The proportional assistance can be adjusted by the clinician to reduce the patient's work of breathing. Several case series of infants with congenital diaphragmatic hernias (CDH) have shown that NAVA may reduce oxygenation index and mean airway pressures. To date, no clinical trial has compared NAVA to standard methods of mechanical ventilation for babies with CDH.

METHODS

The aim of this dual-centre randomised cross-over trial is to compare post-operative NAVA with assist control ventilation (ACV) for infants with CDH. If eligible, infants will be enrolled for a ventilatory support tolerance trial (VSTT) to assess their suitability for randomisation. If clinically stable during the VSTT, infants will be randomised to receive either NAVA or ACV first in a 1:1 ratio for a 4-h period. The oxygenation index, respiratory severity score and cumulative sedative medication use will be measured.

DISCUSSION

Retrospective studies comparing NAVA to ACV in neonates with congenital diaphragmatic hernia have shown the ventilatory mode may improve respiratory parameters and benefit neonates. To our knowledge, this is the first prospective cross-over trial comparing NAVA to ACV.

TRIAL REGISTRATION

NAN-C was prospectively registered on ClinicalTrials.gov NCT05839340  Registered on May 2023.

Correlation and Prediction of Oxygen Index from Oxygen Saturation Index in Neonates with Acute Respiratory Failure

OBJECTIVE

 The aim of this article was to evaluate the correlation between the oxygen index (OI) and the oxygen saturation index (OSI, measured by pulse oximetry and noninvasively) in neonates with acute respiratory failure and to predict the OI from the OSI.

STUDY DESIGN

 A retrospective cohort study was conducted in neonates requiring invasive mechanical ventilation who had arterial blood gas between 2018 and 2019 at a neonatal intensive care unit. The correlation between OI and OSI was analyzed by using the Pearson correlation coefficient.

RESULTS

 A total of 636 measurements from 68 neonates (35 preterm and 33 terms) were recruited into the study. There was a strong correlation between the OI and the OSI (r = 0.90) in all neonates. The correlation between the OI and the OSI in persistent pulmonary hypertension of the newborn, congenital cyanotic heart disease, and other causes of respiratory failure also showed a strong correlation (r = 0.88, 0.93, and 0.88, respectively). The correlation was strong in neonates with an oxygen saturation less than 85% (r = 0.88), those with oxygen saturation ranging from 85 to 95% (r = 0.87), and also in preterm and term infants (gestational age < 28, 28 - 34, 34 - 36, and ≥37 weeks, r = 0.87, 0.92, 0.89, and 0.90, respectively). There were strong accuracy measures of the OI for OI cutoffs of 5, 10, 15, and 20 (area under the curve > 0.85). The equation relating the OI and OSI was represented by: OI = (2.3 × OSI) - 4.

CONCLUSION

 The OSI has a strong correlation with the OI, is a reliable assessor of the severity of respiratory failure in neonates without arterial sampling, and has high accuracy when the OI is less than 40.

KEY POINTS

· OSI is calculated as (FiO2 × mean airway pressure × 100)/SpO2.. · OSI is as effective tool as OI for assessing the severity of pediatric acute respiratory distress syndrome.. · OSI has a strong correlation with OI in neonatal respiratory failure..

Oxygenation saturation index in neonatal hypoxemic respiratory failure

BACKGROUND

This study aimed to assess the validity of the oxygenation saturation index (OSI) and the ratio of oxygen saturation to the fraction of inspired oxygen (FIO2) (S/F ratio) with percutaneous oxygen saturation (OSISpO2 and the Sp/F ratio) and to evaluate the correlation between these values and the oxygen index (OI). It also determined their cut-off values for predicting OI in accordance with neonatal hypoxic respiratory failure severity.

METHODS

We reviewed the data of 77 neonates (gestational age 31.7 ± 6.1 weeks; birthweight, 1768 ± 983 g) requiring invasive mechanical ventilation between 2013 and 2020, 1233 arterial blood gas samples in total. We calculated the OI, OSISpO2, OSI with arterial oxygen saturation (SaO2) (OSISaO2), Sp/F ratio, and the ratio of SaO2 to FIO2 (Sa/F ratio).

RESULTS

The regression and Bland-Altman analysis showed good agreement between OSISpO2 or the Sp/F ratio and OSISaO2 or the Sa/F ratio. Although a significant positive correlation was found between OSISpO2 and OI, OSISpO2 was overestimated in SpO2 > 98% with a higher slope of the fitted regression line than that below 98% of SpO2. Furthermore, receiver-operating characteristic curve analysis using only SpO2 ≤ 98% samples showed that the optimal cut-off points of OSISpO2 and the Sp/F ratio for predicting OI were: OI 5, 3.0 and 332; OI 10, 5.3 and 231; OI 15, 7.7 and 108; OI 20, 11.0 and 149; and OI 25, 17.1 and 103, respectively.

CONCLUSION

The cut-off OSISpO2 and Sp/F ratio values could allow continuous monitoring for oxygenation changes in neonates with the potential for wider clinical applications.

Surfactant status assessment and personalized therapy for surfactant deficiency or dysfunction

Surfactant is a pivotal neonatal drug used both for respiratory distress syndrome due to surfactant deficiency and for more complex surfactant dysfunctions (such as in case of neonatal acute respiratory distress syndrome). Despite its importance, indications for surfactant therapy are often based on oversimplified criteria. Lung biology and modern monitoring provide several diagnostic tools to assess the patient surfactant status and they can be used for a personalized surfactant therapy. This is desirable to improve the efficacy of surfactant treatment and reduce associated costs and side effects. In this review we will discuss these diagnostic tools from a pathophysiological and multi-disciplinary perspective, focusing on the quantitative or qualitative surfactant assays, lung mechanics or aeration measurements, and gas exchange metrics. Their biological and technical characteristics are described with practical information for clinicians. Finally, available evidence-based data are reviewed, and the diagnostic accuracy of the different tools is compared. Lung ultrasound seems the most suitable tool for assessing the surfactant status, while some other promising tests require further research and/or development.

The perinatal period should be considered in neonatal acute respiratory distress syndrome: comparison of the Montreux definition vs. the second pediatric acute lung injury consensus conference definition

Background

The recently developed Montreux definition for neonatal acute respiratory distress syndrome (ARDS) partially differs from the Second Pediatric Acute Lung Injury Consensus Conference (PALICC-2) definition. Here, we compare the Montreux and PALICC-2 definitions regarding morbidity, mortality, and prognosis of neonatal cases of ARDS in order to evaluate which definition is more appropriate for newborns.

Methods

Neonates admitted to our neonatal intensive care unit between 1 January 2018 and 30 September 2019 who met the Montreux or PALICC-2 definition of neonatal ARDS were retrospectively analyzed (n = 472). One comparison was made between application of the Montreux and PALICC-2 definitions to neonates outside the perinatal period (> 7 d after birth). A second comparison was made between a diagnosis of neonatal ARDS within (≤ 7 d of birth) and outside (> 7 d after birth) the perinatal period using the Montreux definition.

Results

No significant differences in morbidity, mortality, severity, therapies, or prognosis were observed between neonates in the extra perinatal group according to the Montreux and PALICC-2 definitions. However, epidemiology, clinical course, and prognosis of neonatal ARDS within the perinatal period did differ from those outside the perinatal period according to the Montreux definition.

Conclusion

Neonates with ARDS within the perinatal period have unique triggers, epidemiology, clinical course, and prognosis, yet a similar pathobiology pattern, to neonates at other ages. Therefore, it may be essential to consider the perinatal period when defining neonatal ARDS.

Estimating Preterm Lung Volume: A Comparison of Lung Ultrasound, Chest Radiography, and Oxygenation

OBJECTIVE

To determine the relationship between lung ultrasound (LUS) examination, chest radiograph (CXR), and radiographic and clinical evaluations in the assessment of lung volume in preterm infants.

STUDY DESIGN

In this prospective cohort study LUS was performed before CXR on 70 preterm infants and graded using (1) a LUS score, (2) an atelectasis score, and (3) measurement of atelectasis depth. Radiographic diaphragm position and radio-opacification were used to determine global and regional radiographic atelectasis. The relationship between LUS, CXR, and oxygenation was assessed using receiver operator characteristic and correlation analysis.

RESULTS

LUS scores, atelectasis scores, and atelectasis depth did not correspond with radiographic global atelectasis (area under receiver operator characteristics curves, 0.54 [95% CI, 0.36-0.71], 0.49 [95% CI, 0.34-0.64], and 0.47 [95% CI, 0.31-0.64], respectively). Radiographic atelectasis of the right upper, right lower, left upper, and left lower quadrants was predicted by LUS scores (0.75 [95% CI, 0.59-0.92], 0.75 [95% CI, 0.62-0.89], 0.69 [95% CI, 0.56-0.82], and 0.63 [95% CI, 0.508-0.751]) and atelectasis depth (0.66 [95% CI, 0.54-0.78], 0.65 [95% CI, 0.53-0.77], 0.63 [95% CI, 0.50-0.76], and 0.56 [95% CI, 0.44-0.70]). LUS findings were moderately correlated with oxygen saturation index (ρ = 0.52 [95% CI, 0.30-0.70]) and saturation to fraction of inspired oxygen ratio (ρ = -0.63 [95% CI, -0.76 to -0.46]). The correlation between radiographic diaphragm position, the oxygenation saturation index, and peripheral oxygen saturation to fraction of inspired oxygen ratio was very weak (ρ = 0.36 [95% CI, 0.11-0.59] and ρ = -0.32 [95% CI, -0.53 to -0.07], respectively).

CONCLUSIONS

LUS assessment of lung volume does not correspond with radiographic diaphragm position preterm infants. However, LUS predicted radiographic regional atelectasis and correlated with oxygenation. The relationship between radiographic diaphragm position and oxygenation was very weak. Although LUS may not replace all radiographic measures of lung volume, LUS more accurately reflects respiratory status in preterm infants.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry: ACTRN12621001119886.

L'utilisation du monoxyde d'azote inhalé chez les nouveau-nés

Le monoxyde d'azote inhalé (NOi), un vasodilatateur pulmonaire sélectif, est utilisé pour le traitement des nouveau-nés en insuffisance respiratoire hypoxémique (IRH) associée à une hypertension pulmonaire persistante du nouveau-né. Idéalement, il doit commencer à être administré après la confirmation échocardiographique de ce type d'hypertension. L'utilisation de NOi est recommandée chez les nouveau-nés peu prématurés ou à terme chez qui survient une IRH malgré des stratégies d'oxygénation ou de ventilation optimales. Cependant, il n'est pas recommandé d'y recourir systématiquement chez les nouveau-nés prématurés sous assistance respiratoire. On peut l'envisager comme traitement de secours chez les nouveau-nés prématurés en IRH précoce associée à une rupture prolongée des membranes ou à un oligoamnios, ou en IRH tardive en cas d'hypertension pulmonaire liée à une dysplasie bronchopulmonaire et accompagnée d'une insuffisance ventriculaire droite marquée. On peut aussi l'envisager chez les nouveau-nés atteints d'une hernie diaphragmatique congénitale qui présentent une IRH persistante, malgré un recrutement pulmonaire optimal, des signes échocardiographiques d'hypertension pulmonaire suprasystémique et un fonctionnement ventriculaire gauche approprié.

Inhaled nitric oxide use in newborns

Inhaled nitric oxide (iNO), a selective pulmonary vasodilator, is used as a therapeutic modality in infants with hypoxemic respiratory failure (HRF) associated with persistent pulmonary hypertension of the newborn (PPHN). iNO should ideally be initiated following echocardiographic confirmation of PPHN. Use of iNO is recommended in late preterm and term infants who develop HRF despite optimal oxygenation and ventilation strategies. However, routine iNO use in preterm infants on respiratory support is not recommended. iNO may be considered as a rescue modality in preterm infants with early-onset HRF when associated with prolonged rupture of membranes or oligohydramnios, or late-onset HRF in the context of bronchopulmonary dysplasia-associated pulmonary hypertension (PH) with severe right ventricular failure. A trial of iNO may also be considered for infants with congenital diaphragmatic hernia with persistent HRF despite optimal lung recruitment, and with echocardiographic evidence of supra-systemic PH and adequate left ventricular function.

Hospital variability in modifiable factors driving coronary artery bypass charges

OBJECTIVE

Coronary artery bypass grafting is associated with significant interhospital variability in charges. Drivers of hospital charge variability remain elusive. We identified modifiable factors associated with statewide interhospital variability in hospital charges for coronary artery bypass grafting.

METHODS

Charge data were used as a surrogate for cost. Society of Thoracic Surgeons data from Maryland institutions and charge data from the Maryland Health Care Commission were linked to characterize interhospital charge variability for coronary artery bypass grafting. Multivariable linear regression was used to identify perioperative factors independently related to coronary artery bypass grafting charges. Of the factors independently associated with charges, we analyzed which factors varied between hospitals.

RESULTS

A total of 10,337 patients underwent isolated coronary artery bypass grafting at 9 Maryland hospitals from 2012 to 2016, of whom 7532 patients were available for analyses. Mean normalized charges for isolated coronary artery bypass grafting varied significantly among hospitals, ranging from $30,000 to $57,000 (P < .001). Longer preoperative length of stay, operating room time, and major postoperative morbidity including stroke, renal failure, prolonged ventilation, reoperation, and deep sternal wound infection were associated with greater hospital charges. Incidence of major postoperative events, except stroke and deep sternal wound infection, was variable between hospitals. In a univariate linear regression model, patient risk profile only accounted for approximately 10% of statistical variance in charges.

CONCLUSIONS

There is significant charge variability for coronary artery bypass grafting among hospitals within the same state. By targeting variation in preoperative length of stay, operating room time, postoperative renal failure, prolonged ventilation, and reoperation, cardiac surgery programs can realize cost savings while improving quality of care for this resource-intense patient population.

Oxygenation index in the first three weeks of life is a predictor of bronchopulmonary dysplasia grade in very preterm infants

BACKGROUND

The new bronchopulmonary dysplasia (BPD) grading system was developed based on its correlation with long-term respiratory and neurodevelopmental outcomes and may provide better personalized prognostication. Identifying early-life predictors for accurate BPD grade prediction may allow interventions to be tailored to individual needs. This study aimed to assess whether oxygenation index (OI) dynamics in the first three weeks of life are a predictor of BPD grade.

METHODS

A single-center retrospective study was performed. Generalized additive mixed modeling was used to model OI trajectories for each BPD grade subgroup. A multinomial regression model was then developed to quantify the association between OI dynamics and BPD grade.

RESULTS

Two hundred fifty-four infants were identified for inclusion in the trajectory modeling. A total of 6,243 OI data points were available for modeling. OI trajectory estimates showed distinct patterns in the three groups, most prominent during the third week of life. The average daily OI change was -0.33 ± 0.52 (n = 85) in the No-BPD group, -0.04 ± 0.75 (n = 82) in the Low-Grade BPD group, and 0.22 ± 0.65 (n = 75) in the High-Grade BPD group (p < 0.001). A multinomial regression analysis showed the initial OI value and the average daily OI change both independently correlated with BPD grade outcomes after adjusting for birth gestation, birth weight z-score, sex, and the duration of invasive ventilation.

CONCLUSION

Early-life OI dynamics may be a useful independent marker for BPD grade prediction. Prospective studies may be warranted to further validate the findings.

Therapeutic response of iNO in preterm infants with hypoxemic respiratory failure

BACKGROUND

Inhaled nitric oxide (iNO) has been used as a rescue treatment for preterm infants with hypoxemic respiratory failure (HRF). However, its effectiveness remains debatable. Thus, in this study, we aimed to examine the impact of iNO therapy on HRF in extremely preterm infants.

METHODS

A retrospective observational study was performed. Extremely preterm infants admitted to our neonatal intensive care unit who received iNO therapy later in their postnatal life were included. The oxygen saturation index (OSI) was used as an index of the severity of respiratory failure.

RESULTS

In total, 30 extremely preterm infants were included in this study. Oxygenation was enhanced after the administration of iNO in infants with HRF. The OSI decreased by more than 20% in 12 patients (40%, positive responder) and did not decrease in 17 patients (57%, negative responder) within the first 6 h of treatment. The iNO initiation day was the significant independent factor associated with a positive response to iNO therapy in extremely preterm infants with HRF.

CONCLUSIONS

iNO therapy was effective in enhancing oxygenation in extremely preterm infants with HRF. Earlier use of iNO was the significant factor associated with a positive therapeutic response to iNO, implying that iNO may be more effective in pulmonary vessels which are less damaged by shorter-term mechanical ventilation.

Prehospital Respiratory Early Warning Score for airway management in-ambulance: A score comparison

BACKGROUND

Prehospital Respiratory Early Warning Scores to estimate the requirement for advanced respiratory support is needed. To develop a prehospital Respiratory Early Warning Score to estimate the requirement for advanced respiratory support.

METHODS

Multicentre, prospective, emergency medical services (EMS)-delivered, longitudinal cohort derivationvalidation study carried out in 59 ambulances and five hospitals across five Spanish provinces. Adults with acute diseases evaluated, supported and discharged to the Emergency Department with high priority were eligible. The primary outcome was the need for invasive or non-invasive respiratory support (NIRS or IRS) in the prehospital scope at the first contact with the patient. The measures included the following: epidemiological endpoints, prehospital vital signs (respiratory rate, pulse oximetry saturation, fraction of inspired oxygen, systolic and diastolic mean blood pressure, heart rate, tympanic temperature and consciousness level by the GCS).

RESULTS

Between 26 Oct 2018 and 26 Oct 2021, we enrolled 5793 cases. For NIRS prediction, the final model of the logistic regression included respiratory rate and pulse oximetry saturation/fraction of inspired oxygen ratio. For the IRS case, the motor response from the Glasgow Coma Scale was also included. The REWS showed an AUC of 0.938 (95% CI: 0.918-0.958), a calibration-in-large of 0.026 and a higher net benefit as compared with the other scores.

CONCLUSIONS

Our results showed that REWS is a remarkably aid for the decision-making process in the management of advanced respiratory support in prehospital care. Including this score in the prehospital scenario could improve patients' care and optimise the resources' management.

The importance of lung recruitability: A novel ultrasound pattern to guide lung recruitment in neonates

BACKGROUND

Lung Ultrasound (LUS)-guided Lung Recruitment Maneuver (LRM) has been shown to possibly reduce ventilator-induced lung injury in preterm infants. However, to avoid potential hemodynamic and pulmonary side effects, the indication to perform the maneuver needs to be supported by early signs of lung recruitability. Recently, a new LUS pattern (S-pattern), obtained during the reopening of collapsed parenchyma, has been described. This study aims to evaluate if this novel LUS pattern is associated with a higher clinical impact of the LUS-guided LRMs.

METHODS

All the LUS-guided rescue LRMs performed on infants with oxygen saturation/fraction of inspired oxygen (S/F) ratio below 200, were included in this cohort study. The primary outcome was to determine if the presence of the S-pattern is associated with the success of LUS-guided recruitment, in terms of the difference between the final and initial S/F ratio (Delta S/F).

RESULTS

We reported twenty-two LUS-guided recruitments, performed in nine patients with a median gestational age of 34 weeks, interquartile range (IQR) 28-35 weeks. The S-pattern could be obtained in 14 recruitments (64%) and appeared early during the procedure, after a median of 2 cmH2O (IQR 1-3) pressure increase. The presence of the S-pattern was significantly associated with the effectiveness of the maneuver as opposed to the cases in which the S-pattern could not be obtained (Delta S/F 110 +/- 47 vs 44 +/- 39, p = 0.01).

CONCLUSIONS

Our results suggest that the presence of the S-pattern may be an early sign of lung recruitability, predicting LUS-guided recruitment appropriateness and efficacy.

Efficacy and safety of endotracheal instillation of iloprost for persistent pulmonary hypertension of the newborn

OBJECTIVE

To determine the efficacy and safety of endotracheal instillation of iloprost as a rescue therapy for persistent pulmonary hypertension of the newborn.

METHODS

Neonates diagnosed with persistent pulmonary hypertension who were unresponsive to standard treatment protocol applied for persistent pulmonary hypertension in our unit, and who were being followed up with mechanical ventilation, were included in the study. Iloprost was instilled endotracheally as a rescue treatment. Systolic pulmonary artery pressure, oxygen saturation index, mean airway pressure, fraction of inspired oxygen, preductal and postductal venous oxygen saturation, heart rate, and blood pressure were recorded before and after 30 minutes of endotracheal iloprost instillation. Adverse events after endotracheal iloprost were recorded.

RESULTS

Twenty neonates were included. The median gestational age and birth weight were found to be 37 (30.5-38) weeks and 2975 (2125-3437.5) grams, respectively. When compared to the period before endotracheal iloprost instillation, systolic pulmonary artery pressure, oxygen saturation index, mean airway pressure, and fraction of inspired oxygen values significantly decreased (p < 0.001, p < 0.001, p = 0.021, p = 0.001, respectively), whereas preductal and postductal oxygen saturation values significantly increased 30 minutes after the endotracheal iloprost instillation (p = 0.002, p < 0.001, respectively). There were no significant differences in heart rate and blood pressure values before and after the iloprost administration. No adverse events were observed.

CONCLUSION

Endotracheal instillation of iloprost was found to be an effective and safe therapy for persistent pulmonary hypertension unresponsive to conventional treatment.

Pulse oximetry for the diagnosis and management of acute respiratory distress syndrome

The diagnosis of acute respiratory distress syndrome (ARDS) traditionally requires calculation of the ratio of partial pressure of arterial oxygen to fraction of inspired oxygen (PaO2/FiO2) using arterial blood, which can be costly and is not possible in many resource-limited settings. By contrast, pulse oximetry is continuously available, accurate, inexpensive, and non-invasive. Pulse oximetry-based indices, such as the ratio of pulse-oximetric oxygen saturation to FiO2 (SpO2/FiO2), have been validated in clinical studies for the diagnosis and risk stratification of patients with ARDS. Limitations of the SpO2/FiO2 ratio include reduced accuracy in poor perfusion states or above oxygen saturations of 97%, and the potential for reduced accuracy in patients with darker skin pigmentation. Application of pulse oximetry to the diagnosis and management of ARDS, including formal adoption of the SpO2/FiO2 ratio as an alternative to PaO2/FiO2 to meet the diagnostic criterion for hypoxaemia in ARDS, could facilitate increased and earlier recognition of ARDS worldwide to advance both clinical practice and research.

Prediction score for prolonged hospital stay in meconium aspiration syndrome: A multicentric collaborative cohort of south India

BACKGROUND AND OBJECTIVE

With improved survival in neonates with meconium aspiration syndrome (MAS), the focus is currently on mitigating the morbidities. The objective of this study was to predict factors determining prolonged hospital stay in neonates with MAS.

MATERIALS AND METHODS

It was a retrospective cohort from five centers of south India between 2018 and 2020. Neonates ≥35 weeks of gestation admitted to neonatal intensive care unit with the diagnosis of MAS and requiring oxygen beyond 24 h of life were included in the study. The morbidities in the neonates with stay ≤7 days (short stay) were compared with >7 days (prolonged stay). Logistic regression by the backward stepwise method was used for predictive score creation.

RESULTS

Out of 347 neonates with MAS discharged home, 103 (29%) had a short stay and 244 (71%) had prolonged stay. The primary support beyond O₂ (continuous positive airway pressure/mechanical ventilation) (42% vs. 83%, p < 0.001), fractional inspired oxygen (FiO₂ ) at 1 h >30% (45% vs. 87%, p < 0.001), hypoxic ischemic encephalopathy (HIE) stage 2 or 3 (1% vs. 27%, p < 0.001), moderate-severe persistent pulmonary artery hypertension (PPHN) (3% vs. 31%, p < 0.001) were independent factors associated with prolonged stay on logistic regression. A prediction model was devised using weighted scores of these four associated morbidities. The clinical score thus developed had 83% sensitivity, 68% specificity for the prediction of prolonged stay (area under curve: 82%, 95% confidence interval [78-87], p < 0.001).

CONCLUSION

More than two-thirds of neonates with MAS had prolonged stay. The primary support beyond oxygen, FiO₂ requirement >30%, Moderate to severe PPHN, HIE stage 2 or 3 were predictive of prolonged stay in neonates with MAS.

Evaluation of Correlation and Agreement between SpO2/FiO2 ratio and PaO2/FiO2 ratio in Neonates

Objectives This article evaluates correlation and agreement between oxygen saturation (SpO2)/fraction of inspired oxygen (FiO2) (SF) ratio and partial pressure of oxygen (PaO2)/FiO2 (PF) ratio. It also derives and validates predictive PF ratio from noninvasive SF ratio measurements for clinically relevant PF ratios and derives SF ratio equivalent of PF ratio cutoffs used to define acute lung injury (ALI, PF < 300) and acute respiratory distress syndrome (ARDS, PF < 200).

Methods Retrospective cohort study including neonates with respiratory failure over a 6-year study period. Correlation and agreement between PF ratio with SF ratio was analyzed by Pearson's correlation coefficient and Bland–Altman analysis. Generalized estimating equation was used to derive PF ratio from measured PF ratio and derive corresponding SF ratio for PF ratio cutoffs for ALI and ARDS.

Results A total of 1,019 paired measurements from 196 neonates with mean 28 (± 4.7) weeks' gestational age and 925 (± 1111) g birth weight were analyzed. Strong correlation was noted between SF ratio and PF ratio (r = 0.90). Derived PF ratios from regression (1/PF = –0.0004304 + 2.0897987/SF) showed strong accuracy measures for PF ratio cutoffs < 200 (area under the curve [AUC]: 0.85) and < 100 (AUC: 0.92) with good agreement. Equivalent SF ratio to define ALI was < 450, moderate ARDS was < 355, and severe ARDS was < 220 with strong accuracy measures (AUC > 0.81, 0.84, and 0.93, respectively).

Conclusion SF ratio correlated strongly with PF ratio with good agreement between derived PF ratio from noninvasive SpO2 source and measure PF ratio. Derived PF ratio may be useful to reliably assess severity of respiratory failure in neonates. Further studies are needed to validate SF ratio with clinical illness severity and outcomes.

Lung UltraSound Targeted Recruitment (LUSTR): A Novel Protocol to Optimize Open Lung Ventilation in Critically Ill Neonates

This study investigated the effectiveness of an original Lung UltraSound Targeted Recruitment (LUSTR) protocol to improve the success of lung recruitment maneuvers (LRMs), which are performed as a rescue approach in critically ill neonates. All the LUSTR maneuvers, performed on infants with an oxygen saturation/fraction of inspired oxygen (S/F) ratio below 200, were included in this case−control study (LUSTR-group). The LUSTR-group was matched by the initial S/F ratio and underlying respiratory disease with a control group of lung recruitments performed following the standard oxygenation-guided procedure (Ox-group). The primary outcome was the improvement of the S/F ratio (Delta S/F) throughout the LRM. Secondary outcomes included the rate of air leaks. Each group was comprised of fourteen LRMs. As compared to the standard approach, the LUSTR protocol was associated with a higher success of the procedure in terms of Delta S/F (110 ± 47.3 vs. 64.1 ± 54.6, p = 0.02). This result remained significant after adjusting for confounding variables through multiple linear regressions. The incidence of pneumothorax was lower, although not reaching statistical significance, in the LUSTR-group (0 vs. 14.3%, p = 0.15). The LUSTR protocol may be a more effective and safer option than the oxygenation-based procedure to guide open lung ventilation in neonates, potentially improving ventilation and reducing the impact of ventilator-induced lung injury.

Outcomes of neonatal congenital diaphragmatic hernia in a non-ECMO center in a middle-income country: a retrospective cohort study

BACKGROUND

Most studies examining survival of neonates with congenital diaphragmatic hernia (CDH) are in high-income countries. We aimed to describe the management, survival to hospital discharge rate, and factors associated with survival of neonates with unilateral CDH in a middle-income country.

METHODS

We retrospectively reviewed the medical notes of neonates with unilateral CDH admitted to a pediatric intensive care unit (PICU) in a tertiary referral center over a 15-year period, from 2003-2017. We described the newborns' respiratory care pathways and then compared baseline demographic, hemodynamic, and respiratory indicators between survivors and non-survivors. The primary outcome measure was survival to hospital discharge.

RESULTS

Altogether, 120 neonates were included with 43.3% (52/120) diagnosed antenatally. Stabilization occurred in 38.3% (46/120) with conventional ventilation, 13.3% (16/120) with high-frequency intermittent positive-pressure ventilation, and 22.5% (27/120) with high frequency oscillatory ventilation. Surgical repair was possible in 75.0% (90/120). The overall 30-day survival was 70.8% (85/120) and survival to hospital discharge was 66.7% (80/120). Survival to hospital discharge tended to improve over time (p > 0.05), from 56.0% to 69.5% before and after, respectively, a service reorganization. For those neonates who could be stabilized and operated on, 90.9% (80/88) survived to hospital discharge. The commonest post-operative complication was infection, occurring in 43.3%. The median survivor length of stay was 32.5 (interquartile range 18.8-58.0) days. Multiple logistic regression modelling showed vaginal delivery (odds ratio [OR] = 4.8; 95% confidence interval [CI] [1.1-21.67]; p = 0.041), Apgar score [Formula: see text] 7 at 5 min (OR = 6.7; 95% CI [1.2-36.3]; p = 0.028), and fraction of inspired oxygen (FiO₂) < 50% at 24 h (OR = 89.6; 95% CI [10.6-758.6]; p < 0.001) were significantly associated with improved survival to hospital discharge.

CONCLUSIONS

We report a survival to hospital discharge rate of 66.7%. Survival tended to improve over time, reflecting a greater critical volume of cases and multi-disciplinary care with early involvement of the respiratory team resulting in improved transitioning from PICU. Vaginal delivery, Apgar score [Formula: see text] 7 at 5 min, and FiO₂ < 50% at 24 h increased the likelihood of survival to hospital discharge.

[Early risk factors for death in neonates with persistent pulmonary hypertension of the newborn treated with inhaled nitric oxide]

OBJECTIVES

To evaluate the early risk factors for death in neonates with persistent pulmonary hypertension of the newborn (PPHN) treated with inhaled nitric oxide (iNO).

METHODS

A retrospective analysis was performed on 105 infants with PPHN (gestational age ≥34 weeks and age <7 days on admission) who received iNO treatment in the Department of Neonatology, Children's Hospital of Nanjing Medical University, from July 2017 to March 2021. Related general information and clinical data were collected. According to the clinical outcome at discharge, the infants were divided into a survival group with 79 infants and a death group with 26 infants. Univariate and multivariate Cox regression analyses were used to evaluate the risk factors for death in infants with PPHN treated with iNO. The receiver operating characteristic (ROC) curve was used to calculate the cut-off values of the factors in predicting the death risk.

RESULTS

A total of 105 infants with PPHN treated with iNO were included, among whom 26 died (26/105, 24.8%). The multivariate Cox regression analysis showed that no early response to iNO (HR=8.500, 95%CI: 3.024-23.887, P<0.001), 1-minute Apgar score ≤3 points (HR=10.094, 95%CI: 2.577-39.534, P=0.001), a low value of minimum PaO2/FiO2 within 12 hours after admission (HR=0.067, 95%CI: 0.009-0.481, P=0.007), and a low value of minimum pH within 12 hours after admission (HR=0.049, 95%CI: 0.004-0.545, P=0.014) were independent risk factors for death. The ROC curve analysis showed that the lowest PaO2/FiO2 value within 12 hours after admission had an area under the ROC curve of 0.783 in predicting death risk, with a sensitivity of 84.6% and a specificity of 73.4% at the cut-off value of 50, and the lowest pH value within 12 hours after admission had an area under the ROC curve of 0.746, with a sensitivity of 76.9% and a specificity of 65.8% at the cut-off value of 7.2.

CONCLUSIONS

Infants with PPHN requiring iNO treatment tend to have a high mortality rate. No early response to iNO, 1-minute Apgar score ≤3 points, the lowest PaO2/FiO2 value <50 within 12 hours after admission, and the lowest pH value <7.2 within 12 hours after admission are the early risk factors for death in such infants. Monitoring and evaluation of the above indicators will help to identify high-risk infants in the early stage.

Can Noninvasive Oxygen Saturation Index Match Invasive Oxygenation Index to Monitor Respiratory Disease in Critically Ill Children?—A Prospective Study

Respiratory illnesses are common indications for mechanical ventilation in children. The adequacy of ventilatory support for oxygenation is measured using arterial blood gas analysis and calculation of oxygenation index (OI). Due to invasive nature of arterial blood sampling needed to calculate OI, several researchers have replaced blood gas-derived partial pressure of oxygen values with oxygen saturation (SpO2) obtained from pulse oximetry. This noninvasive index called oxygen saturation index (OSI) is found to be useful in neonates. Studies in pediatric population is lacking. In this prospective study on mechanically ventilated children, both OI and OSI were determined and compared against alveolar–arterial oxygen difference (AaDO2). A total of 29 children were studied. Both OSI and OI had good correlation of 0.787 and 0.792 with AaDO2, respectively. OSI of 7.3 and 9.4 had good sensitivity and specificity for AaDO2 cutoffs of 344 and 498, which represents moderate and severe respiratory illness, respectively. The correlation coefficients of both OSI and OI are similar against AaDO2. OSI can be used instead of OI for constant monitoring of children on mechanical ventilation. Arterial blood gas analysis and calculation of OI can be reserved for situations where SpO2 measurement is unreliable.

The Decision to Extubate: The Association Between Clinician Impressions and Objective Extubation Readiness Criteria in a Pediatric Intensive Care Unit

Objective Objective tools such as spontaneous breathing trials (SBT) aim to identify patients ready for extubation and shorten the length of mechanical ventilation (MV). Despite passing an SBT, patients sometimes are not extubated based on clinicians' subjective impressions. In this article, we explored the factors that influence the decision to extubate among pediatric intensivists and their association with objective criteria.

Design This is a single-center prospective observational study.

Setting This study was conducted in an academic, multidisciplinary 20-bed pediatric intensive care unit (PICU).

Patients The study group involves mechanically ventilated, orally intubated patients admitted to the PICU from January 1 to June 30, 2019.

Measurements and Main Results Objective clinical data were collected for 650 MV days. Attending surveys about extubation readiness were completed for 419 (64.5%) MV days and 63 extubation events. Extubation occurred on 42% of days after passing an SBT. The primary reasons patients who passed an SBT were not extubated on days were unresolved lung pathology (66.6%) and fluid overload (37.6%). On days without extubation, there was no association between a specific reason for not extubating and SBT result (p > 0.05).

Conclusions In this single-center study, the decision to extubate was not strongly associated with passing an SBT, indicating that clinician impressions, namely unresolved lung pathology and fluid overload, outweighed objective measures for determining extubation readiness. To mitigate morbidities and costs associated with unnecessarily prolonged intubations, a better-defined extubation readiness process is needed to guide the decision to extubate in the pediatric population.

Use of vasopressin in persistent pulmonary hypertension of the newborn: A case series

Treatment of neonates with persistent pulmonary hypertension of newborn includes optimization of ventilatory support, use of pulmonary vasodilators, and/or inotropic support. If refractory to this management, some may require extracorporeal membrane oxygenation. We describe a case series of 10 neonates with refractory persistent pulmonary hypertension of newborn treated with vasopressin in a single tertiary center. Mean initiation time of vasopressin was at 30 h of life with a dose ranging from 10 to 85 milliunits/kg/h. Oxygenation index decreased after 12 h of vasopressin exposure (25 to 11) and mean arterial pressure improved after 1 h (45 to 58 mm Hg). Extracorporeal membrane oxygenation was averted in 50% of the cases with transient hyponatremia as the only notable side effect. Although our findings are exploratory and further research is needed to establish safety and efficacy, our experience suggests that vasopressin may have rescue properties in the management of refractory persistent pulmonary hypertension of newborn.

Progression from sepsis to septic shock and time to treatments in preterm infants with late-onset sepsis

AIM

Late-onset sepsis (LOS) in preterm infants can progress rapidly from minimal clinical signs and symptoms to septic shock which is associated with high mortality. The aim of this study was to describe the progression from sepsis to septic shock and evaluate our management performance with emphasis on time to treatments.

METHODS

This was a retrospective observational study including preterm infants ≤32 weeks gestation with LOS and septic shock defined as the requirement of fluids and vasopressors. Physiological changes and time to first diagnostics and treatments were determined from the point of first appearance of clinical signs and symptoms of sepsis (T_ONSET ).

RESULTS

During the 10-year observational period, 279 infants developed LOS and 25 (8.9%) progressed to septic shock. The median (interquartile range) time from T_ONSET to blood culture, administering antibiotics, fluid bolus and vasopressors was 8.4 (4.8-12.2), 9.2 (5.6-12.4), 14.6 (9.5-34.5) and 22.0 (14.6-44.7) h, respectively. Hypotension and raised lactate were prominent physiological changes in the progression to septic shock. Fluid bolus and vasopressors were administered when blood pressure was 20 and 41% below to what was normal before the infant became unwell. Vasopressors significantly increased blood pressure and heart rate. Mortality rate was 40% with no difference in time to treatments between survivors and non-survivors.

CONCLUSION

Clinical recognition of the onset of sepsis in preterm infants remains difficult and contributes to delay of treatment. Once recognised, early administration of antibiotics, fluid bolus and vasopressors should be prioritised.

Inflammatory Biomarkers Are Associated With a Decline in Functional Status at Discharge in Children With Acute Respiratory Failure: An Exploratory Analysis

Supplemental Digital Content is available in the text.

To evaluate the link between early acute respiratory failure and functional morbidity in survivors using the plasma biomarkers interleukin-8, interleukin-1 receptor antagonist, thrombomodulin, and plasminogen activator inhibitor-1. We hypothesized that children with acute respiratory failure with higher levels of inflammation would have worse functional outcomes at discharge, as measured by Pediatric Overall Performance Category.

Postintubation Decline in Oxygen Saturation Index Predicts Mortality in COVID-19: A Retrospective Pilot Study

Background

Acute respiratory failure from COVID-19 pneumonia is a major cause of death after SARS-CoV-2 infection. We investigated whether PaO₂/FiO₂, oxygenation index (OI), SpO₂/FiO₂, and oxygen saturation index (OSI), commonly used to assess the severity of acute respiratory distress syndrome (ARDS), can predict mortality in mechanically ventilated COVID-19 patients.

Methods

In this single-centered retrospective pilot study, we enrolled 68 critically ill mechanically ventilated adult patients with confirmed COVID-19. Physiological variables were recorded on the day of intubation (day 0) and postintubation days 3 and 7. The association between physiological parameters, PaO₂/FiO₂, OI, SpO₂/FiO₂, and OSI with mortality was assessed using multiple variable logistic regression analysis. Receiver operating characteristic analysis was conducted to evaluate the performance of the predictive models.

Results

The ARDS severity indices were not statistically different on the day of intubation, suggesting similar baseline conditions in nonsurviving and surviving patients. However, these indices were significantly worse in the nonsurviving as compared to surviving patients on postintubation days 3 and 7. On intubation day 3, PaO₂/FiO₂ was 101.0 (61.4) in nonsurviving patients vs. 140.2 (109.6) in surviving patients, p=0.004, and on day 7 106.3 (94.2) vs. 178.0 (69.3), p < 0.001. OI was 135.0 (129.7) in nonsurviving vs. 84.8 (86.1) in surviving patients (p=0.003) on day 3 and 150.0 (118.4) vs. 61.5 (46.7) (p < 0.001) on day 7. OSI was 12.0 (11.7) vs. 8.0 (10.0) (p=0.006) on day 3 and 14.7 (13.2) vs. 6.5 (5.4) (p < 0.001) on day 7. Similarly, SpO₂/FiO₂ was 130 (90) vs. 210 (90) (p=0.003) on day 3 and 130 (90) vs. 230 (50) (p < 0.001) on day 7, while OSI was 12.0 (11.7) vs. 8.0 (10.0) (p=0.006) on day 3 and 14.7 (13.2) vs. 6.5 (5.4) (p < 0.001) on day 7 in the nonsurviving and surviving patients, respectively. All measures were independently associated with hospital mortality, with significantly greater odds ratios observed on day 7. The area under the receiver operating characteristic curve (AUC) for mortality prediction was greatest on intubation day 7 (AUC = 0.775, 0.808, and 0.828 for PaO₂/FiO₂, OI, SpO₂/FiO₂, and OSI, respectively).

Conclusions

Decline in oxygenation indices after intubation is predictive of mortality in COVID-19 patients. This time window is critical to the outcome of these patients and a possible target for future interventions. Future large-scale studies to confirm the prognostic value of the indices in COVID-19 patients are warranted.

Outcomes of infants with severe bronchopulmonary dysplasia in the pediatric intensive care unit

BACKGROUND

Some infants with severe bronchopulmonary dysplasia (sBPD) are referred to higher-level centers for multidisciplinary care, including the pediatric intensive care unit (PICU). However, information regarding these infants is limited in PICUs.

METHODS

We investigated the characteristics and outcomes of preterm infants with sBPD referred to the PICU of a tertiary hospital. This retrospective cohort study included 14 preterm infants with sBPD who were transferred to the PICU beyond 40 weeks' postmenstrual age (PMA) because of weaning failure, from January 1, 2014, to September 30, 2018.

RESULTS

The median age at referral was 47.1 weeks (range, 43.6-55.9 weeks), and the median length of stay in the previous neonatal intensive care unit was 154 days (range, 105.8-202.3 days) after birth. After referral the following major comorbidities were found in the patients: large airway malacia, n = 7 (50.0%); significant upper airway obstruction, n = 3 (21.4%); and pulmonary arterial hypertension, n = 8 patients (57.1%). Finally, eight patients (57.1%) were successfully extubated without tracheostomy. Final respiratory support of the patients was determined at a median PMA of 56 weeks (range, 48-63 weeks). Age at referral (P = 0.023) and large airway obstruction (P = 0.028) were significantly related to a decrease in successful extubation.

CONCLUSION

Based on a timely and individualized multidisciplinary approach, some of the prolonged ventilator-dependent infants, even those beyond term age, could be successfully extubated.

Therapeutic effects and outcomes of rescue high-frequency oscillatory ventilation for premature infants with severe refractory respiratory failure

Despite wide application of high frequency oscillatory ventilation (HFOV) in neonates with respiratory distress, little has been reported about its rescue use in preterm infants. We aimed to evaluate the therapeutic effects of HFOV in preterm neonates with refractory respiratory failure and investigate the independent risk factors of in-hospital mortality. We retrospectively analyzed data collected prospectively (January 2011–December 2018) in four neonatal intensive care units of two tertiary-level medical centers in Taiwan. All premature infants (gestational age 24–34 weeks) receiving HFOV as rescue therapy for refractory respiratory failure were included. A total of 668 preterm neonates with refractory respiratory failure were enrolled. The median (IQR) gestational age and birth weight were 27.3 (25.3–31.0) weeks and 915.0 (710.0–1380.0) g, respectively. Pre-HFOV use of cardiac inotropic agents and inhaled nitric oxide were 70.5% and 23.4%, respectively. The oxygenation index (OI), FiO₂, and AaDO₂ were markedly increased after HFOV initiation (all p < 0.001), and can be decreased within 24–48 h (all p < 0.001) after use of HFOV. 375 (56.1%) patients had a good response to HFOV within 3 days. The final in-hospital mortality rate was 34.7%. No association was found between specific primary pulmonary disease and survival in multivariate analysis. We found preterm neonates with gestational age < 28 weeks, occurrences of sepsis, severe hypotension, multiple organ dysfunctions, initial higher severity of respiratory failure and response to HFOV within the first 72 h were independently associated with final in-hospital mortality. The mortality rate of preterm neonates with severe respiratory failure remains high after rescue HFOV treatment. Aggressive therapeutic interventions to treat sepsis and prevent organ dysfunctions are the suggested strategies to optimize outcomes.

Personalized Medicine for the Management of RDS in Preterm Neonates

Continuous positive airway pressure and surfactant represent the first- and second-line treatment for respiratory distress syndrome in preterm neonates, as European and American guidelines, since 2013 and 2014, respectively, started to recommend surfactant replacement only when continuous positive airway pressure fails. These recommendations, however, are not personalized to the individual physiopathology. Simple clinical algorithms may have improved the diffusion of neonatal care, but complex medical issues can hardly be addressed with simple solutions. The treatment of respiratory distress syndrome is a complex matter and can be only optimized with personalization. We performed a review of tools to individualize the management of respiratory distress syndrome based on physiopathology and actual patients' need, according to precision medicine principles. Advanced oxygenation metrics, lung ultrasound, electrical impedance tomography, and both quantitative and qualitative surfactant assays were examined. When these techniques were investigated with diagnostic accuracy studies, reliability measures have been meta-analysed. Amongst all these tools, quantitative lung ultrasound seems the more developed for the widespread use and has a higher diagnostic accuracy (meta-analytical AUC = 0.952 [95% CI: 0.951-0.953]). Surfactant adsorption (AUC = 0.840 [95% CI: 0.824-0.856]) and stable microbubble test (AUC = 0.800 [95% CI: 0.788-0.812]) also have good reliability, but need further industrial development. We advocate for a more accurate characterization and a personalized approach of respiratory distress syndrome. With the above-described currently available tools, it should be possible to personalize the treatment of respiratory distress syndrome according to physiopathol-ogy.

Ductal Flow Ratio as Measure of Transition in Preterm Infants After Birth: A Pilot Study

Background: Cardiovascular changes during the transition from intra- to extrauterine life, alters the pressure gradient across the ductus arteriosus (DA). DA flow ratio (R-L/L-R) has been suggested to reflect the infant's transitional status and could potentially predict neonatal outcomes after preterm birth. Aim: Determine whether DA flow ratio correlates with oxygenation parameters in preterm infants at 1 h after birth. Methods: Echocardiography was performed in preterm infants born <32 weeks gestational age (GA), as part of an ancillary study. DA flow was measured at 1 h after birth. DA flow ratio was correlated with FiO₂, SpO₂, and SpO₂/FiO₂ (SF) ratio. The DA flow ratio of infants receiving physiological-based cord clamping (PBCC) or time-based cord clamping (TBCC) were compared. Results: Measurements from 16 infants were analysed (median [IQR] GA 29 [27-30] weeks; birthweight 1,176 [951-1,409] grams). R-L DA shunting was 16 [17-27] ml/kg/min and L-R was 110 [81-124] ml/kg/min. The DA flow ratio was 0.18 [0.11-0.28], SpO₂ 94 [93-96]%, FiO₂ was 23 [21-28]% and SF ratio 4.1 [3.3-4.5]. There was a moderate correlation between DA flow ratio and SpO₂ [correlation coefficient (CC) -0.415; p = 0.110], FiO₂ (CC 0.384; p = 0.142) and SF ratio (CC -0.356; p = 0.175). There were no differences in DA flow measurements between infants where PBBC or TBCC was performed. Conclusion: In this pilot study we observed a non-significant positive correlation between DA flow ratio at 1 h after birth and oxygenation parameters in preterm infants.

Clinical Features of Critical Coronavirus Disease 2019 in Children

OBJECTIVES

We sought to describe the presentation, course, and outcomes of hospitalized pediatric coronavirus disease 2019 patients, with detailed description of those requiring mechanical ventilation, and comparisons between critically ill and noncritical hospitalized pediatric patients.

DESIGN

Observational cohort study.

SETTING

Riley Hospital for Children at Indiana University Health in Indianapolis in the early weeks of the coronavirus disease 2019 pandemic.

PATIENTS

All hospitalized pediatric patients with confirmed coronavirus disease 2019 as of May 4, 2020, were included.

INTERVENTIONS

Patients received therapies including hydroxychloroquine, remdesivir, tocilizumab, and convalescent serum and were managed according to an institutional algorithm based on evidence available at the time of presentation.

MEASUREMENTS AND MAIN RESULTS

Of 407 children tested for severe acute respiratory syndrome-coronavirus 2 at our hospital, 24 were positive, and 19 required hospitalization. Seven (36.8%) were critically ill in ICU, and four (21%) required mechanical ventilation. Hospitalized children were predominantly male (14, 74%) and African-American or Hispanic (14, 74%), with a bimodal distribution of ages among young children less than or equal to 2 years old (8, 42%) and older adolescents ages 15-18 (6, 32%). Five of seven (71.4%) of critically ill patients were African-American (n = 3) or Hispanic (n = 2). Critical illness was associated with older age (p = 0.017), longer duration of symptoms (p = 0.036), and lower oxygen saturation on presentation (p = 0.016); with more thrombocytopenia (p = 0.015); higher C-reactive protein (p = 0.031); and lower WBC count (p = 0.039). Duration of mechanical ventilation averaged 14.1 days. One patient died.

CONCLUSIONS

Severe, protracted coronavirus disease 2019 is seen in pediatric patients, including those without significant comorbidities. We observed a greater proportion of hospitalized children requiring mechanical ventilation than has been reported to date. Older children, African-American or Hispanic children, and males may be at risk for severe coronavirus disease 2019 requiring hospitalization. Hypoxia, thrombocytopenia, and elevated C-reactive protein may be useful markers of critical illness. Data regarding optimal management and therapies for pediatric coronavirus disease 2019 are urgently needed.

Extracorporeal membrane oxygenation in the pediatric population - who should go on, and who should not

PURPOSE OF REVIEW

The role of extracorporeal membrane oxygenation (ECMO), a method of providing cardiorespiratory support in instances of cardiac or respiratory failure, in neonates and children continues to expand and evolve. This review details the current landscape of ECMO as it applies to neonates and children.

RECENT FINDINGS

Specifically, this review provides the most recent evidence for which patients should be considered for the various forms of ECMO including venovenous ECMO, venoarterial-ECMO, and extracorporeal cardiopulmonary resuscitation. Specific topics to be discussed include indications and contraindications for the different types of ECMO in neonates and children, anticoagulation strategies and ways to monitor end-organ function, outcomes specific to the different types and populations with a focus on meaningful survival to discharge and neurologic outcomes, and consideration of special populations such as low birth weight infants, traumatically injured patients, and children who received recent bone marrow transplants. This review also discusses still unanswered questions surrounding the most appropriate use of ECMO as its role and applications continue to evolve.

SUMMARY

With rapidly increasing utilization of ECMO, neonatologists and pediatricians should be aware of the most recent evidence guiding its indications, applications, and limitations.

Prediction of outcome in patients with ARDS: A prospective cohort study comparing ARDS-definitions and other ARDS-associated parameters, ratios and scores at intubation and over time

Background

Early recognition of high-risk-patients with acute respiratory distress syndrome (ARDS) might improve their outcome by less protracted allocation to intensified therapy including extracorporeal membrane oxygenation (ECMO). Among numerous predictors and classifications, the American European Consensus Conferenece (AECC)- and Berlin-definitions as well as the oxygenation index (OI) and the Murray-/Lung Injury Score are the most common. Most studies compared the prediction of mortality by these parameters on the day of intubation and/or diagnosis of ARDS. However, only few studies investigated prediction over time, in particular for more than three days.

Objective

Therefore, our study aimed at characterization of the best predictor and the best day(s) to predict 28-days-mortality within four days after intubation of patients with ARDS.

Methods

In 100 consecutive patients with ARDS severity according to OI (mean airway pressure*F_iO₂/p_aO₂), modified Murray-score without radiological points (Murray_mod), AECC- and Berlin-definition, were daily documented for four days after intubation. In the subgroup of 49 patients with transpulmonary thermodilution (TPTD) monitoring (PiCCO), extravascular lung water index (EVLWI) was measured daily.

Primary endpoint

Prediction of 28-days-mortality (Area under the receiver-operating-characteristic curve (ROC-AUC)); IBM SPSS 26.

Results

In the totality of patients the best prediction of 28-days-mortality was found on day-1 and day-2 (mean ROC-AUCs for all predictors/scores: 0.632 and 0.620). OI was the best predictor among the ARDS-scores (AUC=0.689 on day-1; 4-day-mean AUC = 0.625). AECC and Murray_mod had 4-day-means AUCs below 0.6. Among the 49 patients with TPTD, EVLWI (4-day-mean AUC=0.696) and OI (4-day-mean AUC=0.695) were the best predictors. AUCs were 0.789 for OI on day-1, and 0.786 for EVLWI on day-2. In binary regression analysis of patients with TPTD, EVLWI (B=-0.105; Wald=7.294; p=0.007) and OI (B=0.124; Wald=7.435; p=0.006) were independently associated with 28-days-mortality. Combining of EVLWI and OI provided ROC-AUCs of 0.801 (day-1) and 0.824 (day-2). Among the totality of patients, the use of TPTD-monitoring „per se“ and a lower SOFA-score were independently associated with a lower 28-days-mortality.

Conclusions

Prognosis of ARDS-patients can be estblished within two days after intubation. The best predictors were EVLWI and OI and their combination. TPTD-monitoring „per se“ was independently associated with reduced mortality.

Use of Continuous Physiological Monitor Data to Evaluate Doxapram Therapy in Preterm Infants

INTRODUCTION

Evaluation of pharmacotherapy during intensive care treatment is commonly based on subjective, intermittent interpretations of physiological parameters. Real-time visualization and analysis may improve drug effect evaluation. We aimed to evaluate the effects of the respiratory stimulant doxapram objectively in preterm infants using continuous physiological parameters.

METHODS

In this longitudinal observational study, preterm infants who received doxapram therapy were eligible for inclusion. Physiological data (1 Hz) were used to assess respiration and to evaluate therapy effects. The oxygen saturation (SpO2)/fraction of inspired oxygen (FiO2) ratio and the area under the 89% SpO2 curve (duration × saturation depth below target) were calculated as measures of hypoxemia. Regression analyses were performed in 1-h timeframes to discriminate therapy failure (intubation or death) from success (no intubation).

RESULTS

Monitor data of 61 patients with a median postmenstrual age (PMA) at doxapram initiation of 28.7 (IQR 27.6-30.0) weeks were available. The success rate of doxapram therapy was 56%. Doxapram pharmacodynamics were reflected in an increased SpO2 and SpO2/FiO2 ratio as well as a decrease in episodes with saturations below target (SpO2 <89%). The SpO2/FiO2 ratio, corrected for PMA and mechanical ventilation before therapy start, discriminated best between therapy failure and success (highest AUC ROC of 0.83).

CONCLUSION

The use of continuous physiological monitor data enables objective and detailed interpretation of doxapram in preterm infants. The SpO2/FiO2 ratio is the best predictive parameter for therapy failure or success. Further implementation of real-time data analysis and treatment algorithms would provide new opportunities to treat newborns.

Accuracy of oxygen saturation index in determining the severity of respiratory failure among preterm infants with respiratory distress syndrome

BACKGROUND

To evaluate the severity of respiratory failure among newborns with respiratory distress syndrome (RDS), oxygenation index (OI) has been implemented. In the present study, we assessed the accuracy of oxygen saturation index (OSI) in determining the severity of respiratory failure.

METHODS

A cross-sectional study was carried out in the NICUs of two Iranian Hospitals (Tehran, Iran) in 2018. Preterm neonates with RDS entered the study. Immediately after admission, the severity of RDS was determined based on RDS scoring system. Then, 2 CC of arterial blood was withdrawn and sent to laboratory determining blood gases. Simultaneously, the level of peripheral capillary oxygen saturation (SpO₂) was read using pulse oximeter and recorded. OI and OSI were measured using the formulae. Receiver Operating Characteristic curve, Kappa agreement coefficient and accuracy, sensitivity and specificity was used to compare the OI and OSI results.

RESULTS

In the study, 95 neonates were considered. Based on ROC curves, the appropriate cut off with AUC = 0.99 for severe respiratory failure was OSI >8. The sensitivity, specificity, negative predicted value, and positive predicted value for the OSI Cut off >8 were 100, 98, 0.97 and 100%, respectively. The overall accuracy and Kappa agreement between OSI and OI was 0.96 and 0.98%, respectively.

CONCLUSION

Our results showed that OSI with high sensitivity, specificity values could predict the severity of respiratory failure in preterm neonates with RDS.

Comparison of NIV-NAVA and NCPAP in facilitating extubation for very preterm infants

Background

Various types of noninvasive respiratory modalities that lead to successful extubation in preterm infants have been explored. We aimed to compare noninvasive neurally adjusted ventilatory assist (NIV-NAVA) and nasal continuous positive airway pressure (NCPAP) for the postextubation stabilization of preterm infants.

Methods

This retrospective study was divided into two distinct periods, between July 2012 and June 2013 and between July 2013 and June 2014, because NIV-NAVA was applied beginning in July 2013. Preterm infants of less than 30 weeks GA who had been intubated with mechanical ventilation for longer than 24 h and were weaned to NCPAP or NIV-NAVA after extubation were enrolled. Ventilatory variables and extubation failure were compared after weaning to NCPAP or NIV-NAVA. Extubation failure was defined when infants were reintubated within 72 h of extubation.

Results

There were 14 infants who were weaned to NCPAP during Period I, and 2 infants and 16 infants were weaned to NCPAP and NIV-NAVA, respectively, during Period II. At the time of extubation, there were no differences in the respiratory severity score (NIV-NAVA 1.65 vs. NCPAP 1.95), oxygen saturation index (1.70 vs. 2.09) and steroid use before extubation. Several ventilation parameters at extubation, such as the mean airway pressure, positive end-expiratory pressure, peak inspiratory pressure, and FiO₂, were similar between the two groups. SpO₂ and pCO₂ preceding extubation were comparable. Extubation failure within 72 h after extubation was observed in 6.3% of the NIV-NAVA group and 37.5% of the NCPAP group (P = 0.041).

Conclusions

The data in the present showed promising implications for using NIV-NAVA over NCPAP to facilitate extubation.