Decision to extubate extremely preterm infants: art, science or gamble?

Characteristics and Outcomes in Preterm Infants with Extubation Failure in the First Week of Life

OBJECTIVE

 This study aimed to evaluate characteristics and outcomes in preterm infants with extubation failures in their first week of life.

STUDY DESIGN

 Retrospective chart review of infants born between 24 and 27 weeks' gestational age at the Sharp Mary Birch Hospital for Women and Newborns between January 2014 and December 2020 who had an extubation attempt within the first 7 days of life. Infants that were successfully extubated were compared with those who required reintubation in the first 7 days. Maternal and neonatal outcome measures were analyzed.

RESULTS

 A total of 215 extremely preterm infants had an extubation attempt in the first 7 days of life. Forty-six infants (21.4%) failed extubation and were reintubated within the first 7 days. Infants who failed extubation had a lower pH (p < 0.01), increased base deficit (p < 0.01), and more surfactant doses prior to first extubation (p < 0.01). Birth weight, Apgar scores, antenatal steroid doses, and maternal risk factors such as preeclampsia, chorioamnionitis, and duration of ruptured membranes were not different between success and failure groups. Rates of moderate to large patent ductus arteriosus (p < 0.01), severe intraventricular hemorrhage (p < 0.01), posthemorrhagic hydrocephalus (p < 0.05), periventricular leukomalacia (p < 0.01), and retinopathy of prematurity stage 3 or greater (p < 0.05) were higher in the failure group.

CONCLUSION

 In this cohort of extremely preterm infants that failed extubation in the first week of life, there were as increased risk of multiple morbidities. Base deficit, pH, and number of surfactant doses prior to first extubation may be useful tools in predicting which infants are likely to have early extubation success, but this needs prospective study.

KEY POINTS

· Predicting extubation readiness in preterm infants remains challenging.. · Extubation failure is associated with multiple neonatal morbidities.. · Infant clinical characteristics may help predict extubation failure..

Respiratory outcomes and survival after unplanned extubation in the NICU: a prospective cohort study from the SEPREVEN trial

OBJECTIVE

To compare reintubation rates after planned extubation and unplanned extubation (UE) in patients in neonatal intensive care units (NICUs), to analyse risk factors for reintubation after UE and to compare outcomes in patients with and without UE.

DESIGN

Prospective, observational study nested in a randomised controlled trial (SEPREVEN/Study on Epidemiology and PRevention of adverse EVEnts in Neonates). Outcomes were expected to be independent of the intervention tested.

SETTING

12 NICUs in France with a 20-month follow-up, starting November 2015.

PATIENTS

n=2280 patients with a NICU stay >2 days, postmenstrual age ≤42 weeks on admission.

INTERVENTIONS/EXPOSURE

Characteristics of UE (context, timing, sedative administration in the preceding 6 hours, weaning from ventilation at time of UE) and patients.

MAIN OUTCOME MEASURES

Healthcare professional-reported UE rates, reintubation/timing after extubation, duration of mechanical ventilation, mortality and bronchopulmonary dysplasia (BPD).

RESULTS

There were 162 episodes of UE (139 patients, median gestational age (IQR) 27.3 (25.6-31.7) weeks). Cumulative reintubation rates within 24 hours and 7 days of UE were, respectively, 50.0% and 57.5%, compared with 5.5% and 12.3% after a planned extubation. Independent risk factors for reintubation within 7 days included absence of weaning at the time of UE (HR, 95% CI) and sedatives in the preceding 6 hours (HR 1.93, 95% CI 1.04 to 3.60). Mortality at discharge did not differ between patients with planned extubation or UE. UE was associated with a higher risk of BPD.

CONCLUSION

In the SEPREVEN trial, reintubation followed UE in 58% of the cases, compared with 12% after planned extubation.

TRIAL REGISTRATION NUMBER

NCT02598609.

Predicting Extubation Readiness in Preterm Infants Utilizing Machine Learning: A Diagnostic Utility Study

OBJECTIVE

The objective of this study was to predict extubation readiness in preterm infants using machine learning analysis of bedside pulse oximeter and ventilator data.

STUDY DESIGN

This is an observational study with prospective recordings of oxygen saturation (SpO2) and ventilator data from infants <30 weeks of gestation age. Research pulse oximeters collected SpO2 (1 Hz sampling rate) to quantify intermittent hypoxemia (IH). Continuous ventilator metrics were collected (4-5-minute sampling) from bedside ventilators. Data modeling was completed using unbiased machine learning algorithms. Three model sets were created using the following data source combinations: (1) IH and ventilator (IH + SIMV), (2) IH, and (3) ventilator (SIMV). Infants were also analyzed separated by postnatal age (infants <2 or ≥2 weeks of age). Models were compared by area under the receiver operating characteristic curve (AUC).

RESULTS

A total of 110 extubation events from 110 preterm infants were analyzed. Infants had a median gestation age and birth weight of 26 weeks and 825 g, respectively. Of the 3 models presented, the IH + SIMV model achieved the highest AUC of 0.77 for all infants. Separating infants by postnatal age increased accuracy further achieving AUC of 0.94 for <2 weeks of age group and AUC of 0.83 for ≥2 weeks group.

CONCLUSIONS

Machine learning analysis has the potential to enhance prediction accuracy of extubation readiness in preterm infants while utilizing readily available data streams from bedside pulse oximeters and ventilators.

Neonatal respiratory care practice among level III and IV NICUs in New England

OBJECTIVES

To assess respiratory care guidelines and explore variations in management of very low birth weight (VLBW) infants within a collaborative care framework. Additionally, to gather clinical leaders' perspectives on guidelines and preferences for ventilation modalities.

STUDY DESIGN

Leaders from each NICU participated in a practice survey regarding the prevalence of unit clinical guidelines, and management, at many stages of care.

RESULTS

Units have an average of 4.3 (±2.1) guidelines, of 9 topics queried. Guideline prevalence was not associated with practice or outcomes. An FiO2 requirement of 0.3-0.4 and a CPAP of 6-7 cmH2O, are the most common thresholds for surfactant administration, which is most often done after intubation, and followed by weaning from ventilatory support. Volume targeted ventilation is commonly used. Extubation criteria vary widely.

CONCLUSIONS

Results identify trends and areas of variation and suggest that the presence of guidelines alone is not predictive of outcome.

Weaning from mechanical ventilation and assessment of extubation readiness

Tremendous advancements in neonatal respiratory care have contributed to the improved survival of extremely preterm infants (gestational age ≤ 28 weeks). While mechanical ventilation is often considered one of the most important breakthroughs in neonatology, it is also associated with numerous short and long-term complications. For those reasons, clinical research has focused on strategies to avoid or reduce exposure to mechanical ventilation. Nonetheless, in the extreme preterm population, 70-100% of infants born 22-28 weeks of gestation are exposed to mechanical ventilation, with nearly 50% being ventilated for ≥ 3 weeks. As contemporary practices have shifted towards selectively reserving mechanical ventilation for those patients, mechanical ventilation weaning and extubation remain a priority yet offer a heightened challenge for clinicians. In this review, we will summarize the evidence for different strategies to expedite weaning and assess extubation readiness in preterm infants, with a particular focus on extremely preterm infants.

Optimal timing of extubation in preterm infants

In neonatal intensive care, endotracheal intubation is usually performed as an urgent or semi-urgent procedure in infants with critical or unstable conditions related to progressive respiratory failure. Extubation is not. Patients undergoing extubation are typically stable, with improved respiratory function. The key elements to facilitating extubation are to recognize improvement in respiratory status, promote weaning of mechanical ventilation, and accurately identify readiness for removal of the endotracheal tube. Therefore, extubation should be a planned and well-organized procedure. In this review, we will appraise the evidence for existing predictors of extubation readiness and provide patient-specific, pathophysiology-derived strategies to optimize the timing and success of extubation in neonates, with a focus on extremely preterm infants.

Development and validation of a prediction model for evaluating extubation readiness in preterm infants

Successful early extubation has advantages not only in terms of short-term respiratory morbidities and survival but also in terms of long-term neurodevelopmental outcomes in preterm infants. However, no consensus exists regarding the optimal protocol or guidelines for extubation readiness in preterm infants. Therefore, the decision to extubate preterm infants was almost entirely at the attending physician's discretion. We identified robust and quantitative predictors of success or failure of the first planned extubation attempt before 36 weeks of post-menstrual age in preterm infants (<32 weeks gestational age) and developed a prediction model for evaluating extubation readiness using these predictors. Extubation success was defined as the absence of reintubation within 72 h after extubation. This observational cohort study used data from preterm infants admitted to the neonatal intensive care unit of Seoul National University Bundang Hospital in South Korea between July 2003 and June 2019 to identify predictors and develop and test a predictive model for extubation readiness. Data from preterm infants included in the Medical Informative Medicine for Intensive Care (MIMIC-III) database between 2001 and 2008 were used for external validation. From a machine learning model using predictors such as demographics, periodic vital signs, ventilator settings, and respiratory indices, the area under the receiver operating characteristic curve and average precision of our model were 0.805 (95% confidence interval [CI], 0.802-0.809) and 0.917, respectively in the internal validation and 0.715 (95% CI, 0.713-0.717) and 0.838, respectively in the external validation. Our prediction model (NExt-Predictor) demonstrated high performance in assessing extubation readiness in both internal and external validations.

Accuracy of lung and diaphragm ultrasound in predicting infant weaning outcomes: a systematic review and meta-analysis

Background

Although lung and diaphragm ultrasound are valuable tools for predicting weaning results in adults with MV, their relevance in children is debatable. The goal of this meta-analysis was to determine the predictive value of lung and diaphragm ultrasound in newborn weaning outcomes.

Methods

For eligible studies, the databases MEDLINE, Web of Science, Cochrane Library, PubMed, and Embase were thoroughly searched. The Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) method was used to evaluate the study's quality. Results were gathered for sensitivity, specificity, diagnostic odds ratio (DOR), and the area under the curve of summary receiver operating characteristic curves (AUSROC). To investigate the causes of heterogeneity, subgroup analyses and meta-regression were conducted.

Results

A total of 11 studies were suitable for inclusion in the meta-analysis, which included 828 patients. The pooled sensitivity and specificity of lung ultrasound (LUS) were 0.88 (95%CI, 0.85-0.90) and 0.81 (95%CI, 0.75-0.87), respectively. The DOR for diaphragmatic excursion (DE) is 13.17 (95%CI, 5.65-30.71). The AUSROC for diaphragm thickening fraction (DTF) is 0.86 (95%CI, 0.82-0.89). The most sensitive and specific method is LUS. The DE and DTF were the key areas where study heterogeneity was evident.

Conclusions

Lung ultrasonography is an extremely accurate method for predicting weaning results in MV infants. DTF outperforms DE in terms of diaphragm ultrasound predictive power.

Automated prediction of extubation success in extremely preterm infants: the APEX multicenter study

BACKGROUND

Extremely preterm infants are frequently subjected to mechanical ventilation. Current prediction tools of extubation success lacks accuracy.

METHODS

Multicenter study including infants with birth weight ≤1250 g undergoing their first extubation attempt. Clinical data and cardiorespiratory signals were acquired before extubation. Primary outcome was prediction of extubation success. Automated analysis of cardiorespiratory signals, development of clinical and cardiorespiratory features, and a 2-stage Clinical Decision-Balanced Random Forest classifier were used. A leave-one-out cross-validation was done. Performance was analyzed by ROC curves and determined by balanced accuracy. An exploratory analysis was performed for extubations before 7 days of age.

RESULTS

A total of 241 infants were included and 44 failed (18%) extubation. The classifier had a balanced accuracy of 73% (sensitivity 70% [95% CI: 63%, 76%], specificity 75% [95% CI: 62%, 88%]). As an additional clinical-decision tool, the classifier would have led to an increase in extubation success from 82% to 93% but misclassified 60 infants who would have been successfully extubated. In infants extubated before 7 days of age, the classifier identified 16/18 failures (specificity 89%) and 73/105 infants with success (sensitivity 70%).

CONCLUSIONS

Machine learning algorithms may improve a balanced prediction of extubation outcomes, but further refinement and validation is required.

IMPACT

A machine learning-derived predictive model combining clinical data with automated analyses of individual cardiorespiratory signals may improve the prediction of successful extubation and identify infants at higher risk of failure with a good balanced accuracy. Such multidisciplinary approach including medicine, biomedical engineering and computer science is a step forward as current tools investigated to predict extubation outcomes lack sufficient balanced accuracy to justify their use in future trials or clinical practice. Thus, this individualized assessment can optimize patient selection for future trials of extubation readiness by decreasing exposure of low-risk infants to interventions and maximize the benefits of those at high risk.

Accuracy of lung and diaphragm ultrasound in predicting successful extubation in extremely preterm infants: A prospective observational study

OBJECTIVE

Chest ultrasound has emerged as a promising tool in predicting extubation readiness in adults and children, yet its utility in preterm infants is lacking. Our aim was to assess the utility of lung ultrasound severity score (LUSS) and diaphragmatic function in predicting extubation readiness in extremely preterm infants.

STUDY DESIGN

In this prospective cohort study, preterm infants < 28 weeks gestational age (GA) who received invasive mechanical ventilation for ≥12 h were enrolled. Chest ultrasound was performed before extubation. The primary outcome was lung ultrasound accuracy for predicting successful extubation at 3 days. Descriptive statistics and logistic regression were done using SPSS version 22.

RESULTS

We enrolled 45 infants, of whom 36 (80%) were successfully extubated. GA and postmenstrual age (PMA) at extubation were significantly higher in the successful group. The LUSS was significantly lower in the successful group compared to failed group (11.9 ± 3.2 vs. 19.1 ± 3.1 p < 0.001). The two groups had no statistically significant difference in diaphragmatic excursion or diaphragmatic thickness fraction. Logistic regression analysis controlling for GA and PMA at extubation showed LUSS was an independent predictor for successful extubation (odd ratio 0.46, 95% confidence interval [0.23-0.9], p = 0.02). The area under the receiver operating characteristic curve was 0.95 (p ˂ 0.001) for LUSS, and a cut-off value of ≥15 had 95% sensitivity and 85% specificity in detecting extubation failure.

CONCLUSION

In extremely preterm infants, lung ultrasound has good accuracy for predicting successful extubation. However, diaphragmatic measurements were not reliable predictors.

Associations between unit workloads and outcomes of first extubation attempts in extremely premature infants below a gestational age of 26 weeks

Objective

The objective was to explore whether high workloads in neonatal intensive care units were associated with short-term respiratory outcomes of extremely premature (EP) infants born <26 weeks of gestational age.

Methods

This was a population-based study using data from the Norwegian Neonatal Network supplemented by data extracted from the medical records of EP infants <26 weeks GA born from 2013 to 2018. To describe the unit workloads, measurements of daily patient volume and unit acuity at each NICU were used. The effect of weekend and summer holiday was also explored.

Results

We analyzed 316 first planned extubation attempts. There were no associations between unit workloads and the duration of mechanical ventilation until each infant's first extubation or the outcomes of these attempts. Additionally, there were no weekend or summer holiday effects on the outcomes explored. Workloads did not affect the causes of reintubation for infants who failed their first extubation attempt.

Conclusion

Our finding that there was no association between the organizational factors explored and short-term respiratory outcomes can be interpreted as indicating resilience in Norwegian neonatal intensive care units.

Organizational Risk Factors and Clinical Impacts of Unplanned Extubation in the Neonatal Intensive Care Unit

OBJECTIVES

To assess the association between organizational factors and unplanned extubation events in the neonatal intensive care unit (NICU) and to evaluate the association between unplanned extubation event and bronchopulmonary dysplasia (BPD) among infants born at <29 weeks of gestational age.

STUDY DESIGN

This is a retrospective cohort study of infants admitted to a tertiary care NICU between 2016 and 2019. Nursing provision ratios, daily nursing overtime hours/total nursing hours ratio, and unit occupancy were compared between days with and days without unplanned extubation events. The association between unplanned extubation events (with and without reintubation) and the risk of BPD was evaluated in infants born at <29 weeks who required mechanical ventilation using a propensity score-matched cohort. Multivariable logistic regression analysis was used to assess the association between exposures and outcomes while adjusting for confounders.

RESULTS

On 108 of 1370 days there was ≥1 unplanned extubation event for a total of 116 unplanned extubation event events. Higher median nursing overtime hours (20 hours vs 16 hours) and overtime ratios (3.3% vs 2.5%) were observed on days with an unplanned extubation event compared with days without an unplanned extubation event (P = .01). Overtime ratio was associated with higher adjusted odds of a unplanned extubation event (aOR, 1.09; 95% CI, 1.01-1.18). In the subgroup of infants born at <29 weeks, those with an unplanned extubation event who were reintubated had a longer postmatching duration of mechanical ventilation (aOR, 13.06; 95% CI, 4.88-37.69) and odds of BPD (aOR, 2.86; 95% CI, 1.01-8.58) compared with those without an unplanned extubation event.

CONCLUSIONS

Nursing overtime ratio is associated with an increased number of unplanned extubation events in the NICU. In infants born at <29 weeks of gestational age, reintubation after an unplanned extubation event is associated with a longer duration of mechanical ventilation and increased risk of BPD.

Impact of early respiratory care for extremely preterm infants

Despite advances in neonatal intensive care, more than half of surviving infants born extremely preterm (EP; < 28 weeks' gestation) develop bronchopulmonary dysplasia (BPD). Prevention of BPD is critical because of its associated mortality and morbidity, including adverse neurodevelopmental outcomes and respiratory health in later childhood and beyond. The respiratory care of EP infants begins before birth, then continues in the delivery room and throughout the primary hospitalization. This chapter will review the evidence for interventions after birth that might improve outcomes for infants born EP, including the timing of umbilical cord clamping, strategies to avoid or minimize exposure to mechanical ventilation, modes of mechanical ventilation and non-invasive respiratory support, oxygen saturation targets, postnatal corticosteroids and other adjunct therapies.