Patterns of Use of Heated Humidified High-Flow Nasal Cannula Therapy in PICUs in the United Kingdom and Republic of Ireland

High-Flow Nasal Cannula Versus Nasal Prong Bubble Continuous Positive Airway Pressure in Children With Moderate to Severe Acute Bronchiolitis: A Randomized Controlled Trial

OBJECTIVES

To compare high-flow nasal cannula (HFNC) versus nasal prong bubble continuous positive airway pressure (b-CPAP) in children with moderate to severe acute bronchiolitis.

DESIGN

A randomized controlled trial was carried out from August 2019 to February 2022. (Clinical Trials Registry of India number CTRI/2019/07/020402).

SETTING

Pediatric emergency ward and ICU within a tertiary care center in India.

PATIENTS

Children 1-23 months old with moderate to severe acute bronchiolitis.

INTERVENTION

Comparison of HFNC with b-CPAP, using a primary outcome of treatment failure within 24 hours of randomization, as defined by any of: 1) a 1-point increase in modified Wood's clinical asthma score (m-WCAS) above baseline, 2) a rise in respiratory rate (RR) greater than 10 per minute from baseline, and 3) escalation in respiratory support. The secondary outcomes were success rate after crossover, if any, need for mechanical ventilation (invasive/noninvasive), local skin lesions, length of hospital stay, and complications.

RESULTS

In 118 children analyzed by intention-to-treat, HFNC (n = 59) versus b-CPAP (n = 59) was associated with a lower failure rate (23.7% vs. 42.4%; relative risk [95% CI], RR 0.56 [95% CI, 0.32-0.97], p = 0.031). The Cox proportion model confirmed a lower hazard of treatment failure in the HFNC group (adjusted hazard ratio 0.48 [95% CI, 0.25-0.94], p = 0.032). No crossover was noted. A lower proportion escalated to noninvasive ventilation in the HFNC group (15.3%) versus the b-CPAP group (15.3% vs. 39% [RR 0.39 (95% CI, 0.20-0.77)], p = 0.004). The HFNC group had a longer median (interquartile range) duration of oxygen therapy (4 [3-6] vs. 3 [3-5] d; p = 0.012) and hospital stay (6 [5-8.5] vs. 5 [4-7] d, p = 0.021). No significant difference was noted in other secondary outcomes.

CONCLUSION

In children aged one to 23 months with moderate to severe acute bronchiolitis, the use of HFNC therapy as opposed to b-CPAP for early respiratory support is associated with a lower failure rate and, secondarily, a lower risk of escalation to mechanical ventilation.

Extubation to High-Flow Nasal Cannula in Infants Following Cardiac Surgery: A Retrospective Cohort Study

High-flow nasal cannula (HFNC) therapy is commonly used in the pediatric intensive care unit (PICU) for postextubation respiratory support. This hypothesis-generating retrospective cohort study aimed to compare postextubation PICU length of stay in infants extubated to HFNC and low flow oxygen (LF) in PICU following cardiac surgery. Of 136 infants (newborn to 1 year) who were intubated and mechanically ventilated in PICU following cardiac surgery, 72 (53%) were extubated to HFNC and 64 (47%) to LF. Compared with patients extubated to LF, those extubated to HFNC had significantly longer durations of cardiopulmonary bypass (152 vs. 109 minutes; p  = 0.002), aortic cross-clamp (90 vs. 63 minutes; p  = 0.003), and invasive mechanical ventilation (3.2 vs. 1.6 days; p  < 0.001), although demographic and preoperative clinical variables were similar. No significant difference was observed in postextubation PICU length of stay between HFNC and LF groups in unadjusted analysis (3.3 vs. 2.6 days, respectively; p  = 0.19) and after controlling for potential confounding variables (F [1,125] = 0.17, p  = 0.68, R 2  = 0.16). Escalation of therapy was similar between HFNC and LF groups (8.3 vs. 14.1%; p  = 0.41). HFNC was effective as rescue therapy for six patients in the LF group requiring escalation of therapy. Need for reintubation was similar between HFNC and LF groups (8.3 vs. 4.7%; p  = 0.5). Although extubation to HFNC was associated with a trend toward longer postextubation PICU length of stay and was successfully used as rescue therapy for several infants extubated to LF, our results must be interpreted with caution given the limitations of our study.

Improving Outcomes for Bronchiolitis Patients After Implementing a High-Flow Nasal Cannula Holiday and Standardizing Discharge Criteria in a PICU

OBJECTIVES

To decrease length of high-flow nasal cannula (HFNC), PICU, and hospital length of stay (LOS).

DESIGN

Quality improvement project.

SETTING

A quaternary academic PICU.

PATIENTS

Patients with bronchiolitis less than 24 months old.

INTERVENTIONS

After initial implementation of a respiratory therapist (RT)-driven HFNC protocol (Plan-Do-Study-Act [PDSA] 1) in October 2017, additional interventions included adjusting HFNC wean rate (PDSA 2) in July 2020, a HFNC holiday (PDSA 3), and standardized discharge criteria (PDSA 4) in October 2021.

MEASUREMENTS AND MAIN RESULTS

Duration of HFNC was used as the primary outcome measure. PICU LOS and hospital LOS were used as secondary outcome measures. Noninvasive ventilation use, invasive mechanical ventilation use, and 7-day PICU and hospital readmission rates were used as balancing measures. A total of 1,310 patients were included in this study. Patients in PDSA 2, PDSA 3 and 4 groups were older compared with pre-intervention and PDSA 1 (median of 9 and 10 mo compared with 8 mo; p = 0.01). HFNC duration decreased from 2.5 to 1.8 days after PDSA 1, then to 1.3 days after PDSA 2. PICU LOS decreased from 2.6 to 2.1 days after PDSA 1, 1.8 days after PDSA 2, and 1.5 days after PDSA 3 and 4. Hospital LOS decreased from 5.7 to 4.5 days after PDSA 1, 3.1 days after PDSA 2, and 2.7 days after PDSA 3 and 4. The use of noninvasive ventilation and invasive mechanical ventilation decreased throughout the study from 23.2% in the pre-intervention group, to 6.9% at the end of the project. The 7-day PICU and hospital readmission rates did not increase after implementation. The percentage of patients discharged from the PICU increased from 6.2% to 21.5%.

CONCLUSIONS

Modifications to an existing RT-driven HFNC protocol and standardization of discharge criteria led to an improvement in outcomes for patients admitted to the PICU with bronchiolitis without an increase in adverse events.

Commentary on the First-Line Support for Assistance in Breathing in Children Trials on Noninvasive Respiratory Support: Taking a Closer Look

Noninvasive respiratory support modalities such as high-flow nasal cannula (HFNC) therapy and continuous positive airway pressure (CPAP) are used frequently in pediatric critical care to support acutely ill children with respiratory failure (step-up management) and children following extubation (step-down management). Although there are several observational studies and database analyses comparing the efficacy of HFNC and CPAP, and a few small randomized clinical trials (RCTs), until recently, there were no large RCTs comparing the two modalities in a mixed group of critically ill children. In the first half of 2022, results from the First-Line Support for Assistance in Breathing in Children (FIRST-ABC) trials were published; these comprised a master protocol of two trials: one in acutely ill children (step-up RCT) and one in extubated children (step-down RCT). Each of these pragmatic trials randomized 600 children to either HFNC or CPAP when the treating clinician decided that noninvasive respiratory support beyond standard oxygen therapy was required. The primary outcome was time to liberation from all forms of respiratory support (invasive and noninvasive), excluding supplemental oxygen. The FIRST-ABC trials represent a significant advance in the field of noninvasive respiratory support, which has traditionally been evidence-poor and associated with considerable variability in clinical practice. In this article, we provide an overview of how the FIRST-ABC trials were conceived and conducted, our view on the results, and how the trial findings have changed our clinical practice.

Commentary on High-Flow Nasal Cannula and Continuous Positive Airway Pressure Practices After the First-Line Support for Assistance in Breathing in Children Trials

Continuous positive airway pressure (CPAP) and heated humidified high-flow nasal cannula (HFNC) are commonly used to treat children admitted to the PICU who require more respiratory support than simple oxygen therapy. Much has been published on these two treatment modalities over the past decade, both in Pediatric Critical Care Medicine (PCCM ) and elsewhere. The majority of these studies are observational analyses of clinical, administrative, or quality improvement datasets and, therefore, are only able to establish associations between exposure to treatment and outcomes, not causation. None of the initial randomized clinical trials comparing HFNC and CPAP were definitive due to their relatively small sample sizes with insufficient power for meaningful clinical outcomes (e.g., escalation to bilevel noninvasive ventilation or intubation, duration of PICU-level respiratory support, mortality) and often yielded ambiguous findings or conflicting results. The recent publication of the First-Line Support for Assistance in Breathing in Children (FIRST-ABC) trials represented a major step toward understanding the role of CPAP and HFNC use in critically ill children. These large, pragmatic, randomized clinical trials examined the efficacy of CPAP and HFNC either for "step up" (i.e., escalation in respiratory support) during acute respiratory deterioration or for "step down" (i.e., postextubation need for respiratory support) management. This narrative review examines the body of evidence on HFNC published in PCCM , contextualizes the findings of randomized clinical trials of CPAP and HFNC up to and including the FIRST-ABC trials, provides guidance to PICU clinicians on how to implement the literature in current practice, and discusses remaining knowledge gaps and future research priorities.

The United Kingdom Paediatric Critical Care Society Study Group: The 20-Year Journey Toward Pragmatic, Randomized Clinical Trials

Over the past two decades, pediatric intensive care research networks have been formed across North America, Europe, Asia, and Australia/New Zealand. The U.K. Paediatric Critical Care Society Study Group (PCCS-SG) has over a 20-year tradition of fostering collaborative research, leading to the design and successful conduct of randomized clinical trials (RCTs). To date, the PCCS-SG network has delivered 13 different multicenter RCTs, covering a spectrum of study designs, methodologies, and scale. Lessons from the early years have led PCCS-SG to now focus on the entire process needed for developing an RCT, starting from robust preparatory steps such as surveys, data analysis, and feasibility work through to a definitive RCT. Pilot RCTs have been an important part of this process as well. Facilitators of successful research have included the presence of a national registry to facilitate efficient data collection; close partnerships with established Clinical Trials Units to bring together clinicians, methodologists, statisticians, and trial managers; greater involvement of transport teams to recruit patients early in trials of time-sensitive interventions; and the funded infrastructure of clinical research staff within the National Health Service to integrate research within the clinical service. The informal nature of PCCS-SG has encouraged buy-in from clinicians. Greater international collaboration and development of embedded trial platforms to speed up the generation and dissemination of trial findings are two key future strategic goals for the PCCS-SG research network.

Mechanical Ventilation and Respiratory Support in the Pediatric Intensive Care Unit

Children admitted to the pediatric intensive care unit often require respiratory support for the treatment of respiratory distress and failure. Respiratory support comprises both noninvasive modalities (ie, heated humidified high-flow nasal cannula, continuous positive airway pressure, bilevel positive airway pressure, negative pressure ventilation) and invasive mechanical ventilation. In this article, we review the various essential elements and considerations involved in the planning and application of respiratory support in the treatment of the critically ill children.

Comparison of Two Weaning Methods from Heated Humidified High-Flow Nasal Cannula Therapy in Pediatric Intensive Care Unit

Background and Objective: Although high-flow nasal cannula (HFNC) is widely used in children, there is no consensus on the methods for starting, maintenance, and weaning. The aim of this study was to compare weaning methods in children. Methods: The study included all patients in pediatric intensive care unit (PICU) who were started on HFNC treatment. The respiratory assessment score was used in the decisions for starting, continuing, and weaning from HFNC. The patients who responded and for whom weaning was planned were randomized by month into 2 groups as directly weaned from HFNC and weaned by reducing the flow. Success rates, treatment, and length of stay (LOS) in weaning methods were compared. Results: Of the 145 patients initially included in the study, 32 (22%) were excluded, and analysis was made of 113 patients. Successful weaning from HFNC was obtained in 76.9% of the patients, in 82.1% of flow weaning, and 73.6% of direct weaning, with no statistically significant difference determined between the groups (P = 0.286). The median duration of HFNC and the median LOS in PICU were determined to be statistically significantly shorter in direct weaning than in flow weaning [36 h interquartile range (IQR) 24-48 h] versus 60 h (IQR 60-72 h), P < 0.001 and 6 days (4-14 days) versus 9.5 days (5.25-20.75 days, P = 0.043, respectively). Conclusion: In patients who responded to HFNC in PICU, the responses to direct weaning and flow reduction were seen to be similar. In patients directly weaned off, both the HFNC duration and LOS in PICU were significantly shorter.

Effect of High-Flow Nasal Cannula Therapy vs Continuous Positive Airway Pressure Following Extubation on Liberation From Respiratory Support in Critically Ill Children: A Randomized Clinical Trial

IMPORTANCE

The optimal first-line mode of noninvasive respiratory support following extubation of critically ill children is not known.

OBJECTIVE

To evaluate the noninferiority of high-flow nasal cannula (HFNC) therapy as the first-line mode of noninvasive respiratory support following extubation, compared with continuous positive airway pressure (CPAP), on time to liberation from respiratory support.

DESIGN, SETTING, AND PARTICIPANTS

This was a pragmatic, multicenter, randomized, noninferiority trial conducted at 22 pediatric intensive care units in the United Kingdom. Six hundred children aged 0 to 15 years clinically assessed to require noninvasive respiratory support within 72 hours of extubation were recruited between August 8, 2019, and May 18, 2020, with last follow-up completed on November 22, 2020.

INTERVENTIONS

Patients were randomized 1:1 to start either HFNC at a flow rate based on patient weight (n = 299) or CPAP of 7 to 8 cm H2O (n = 301).

MAIN OUTCOMES AND MEASURES

The primary outcome was time from randomization to liberation from respiratory support, defined as the start of a 48-hour period during which the child was free from all forms of respiratory support (invasive or noninvasive), assessed against a noninferiority margin of an adjusted hazard ratio (HR) of 0.75. There were 6 secondary outcomes, including mortality at day 180 and reintubation within 48 hours.

RESULTS

Of the 600 children who were randomized, 553 children (HFNC, 281; CPAP, 272) were included in the primary analysis (median age, 3 months; 241 girls [44%]). HFNC failed to meet noninferiority, with a median time to liberation of 50.5 hours (95% CI, 43.0-67.9) vs 42.9 hours (95% CI, 30.5-48.2) for CPAP (adjusted HR, 0.83; 1-sided 97.5% CI, 0.70-∞). Similar results were seen across prespecified subgroups. Of the 6 prespecified secondary outcomes, 5 showed no significant difference, including the rate of reintubation within 48 hours (13.3% for HFNC vs 11.5 % for CPAP). Mortality at day 180 was significantly higher for HFNC (5.6% vs 2.4% for CPAP; adjusted odds ratio, 3.07 [95% CI, 1.1-8.8]). The most common adverse events were abdominal distension (HFNC: 8/281 [2.8%] vs CPAP: 7/272 [2.6%]) and nasal/facial trauma (HFNC: 14/281 [5.0%] vs CPAP: 15/272 [5.5%]).

CONCLUSIONS AND RELEVANCE

Among critically ill children requiring noninvasive respiratory support following extubation, HFNC compared with CPAP following extubation failed to meet the criterion for noninferiority for time to liberation from respiratory support.

TRIAL REGISTRATION

isrctn.org Identifier: ISRCTN60048867.

Hospital Charges Associated With Critical Bronchiolitis From 2009 to 2019

OBJECTIVES

To evaluate the contribution of PICU care to increasing hospital charges for patients with bronchiolitis over a 10-year study period.

DESIGN

In this retrospective multicenter study, changes in annual hospital charges (adjusted for inflation) were analyzed using linear regression for subjects admitted to the PICU with invasive mechanical ventilation (PICU + IMV) and without IMV (PICU - IMV), and for children not requiring PICU care.

SETTING

Free-standing children's hospitals contributing to the Pediatric Health Information System (PHIS) database.

SUBJECTS

Children less than 2 years with bronchiolitis discharged from a PHIS hospital between July 2009 and June 2019. Subjects were categorized as high risk if they were born prematurely or had a chronic complex condition.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

PICU patients were 26.5% of the 283,006 included subjects but accrued 66% of the total $14.83 billion in charges. Annual charges increased from $1.01 billion in 2009-2010 to $2.07 billion in 2018-2019, and PICU patients accounted for 83% of this increase. PICU + IMV patients were 22% of all PICU patients and accrued 64% of all PICU charges, but PICU - IMV patients without a high-risk condition had the highest relative increase in annual charges, increasing from $76.7 million in 2009-2010 to $377.9 million in 2018-2019 (374% increase, ptrend < 0.001).

CONCLUSIONS

In a multicenter cohort study of children hospitalized with bronchiolitis, PICU patients, especially low-risk children without the need for IMV, were the highest driver of increased hospital charges over a 10-year study period.

Non-Invasive Respiratory Support During Pediatric Critical Care Transport: A Retrospective Cohort Study

Non-invasive respiratory support (NRS) including high flow nasal cannula (HFNC), continuous positive airway pressure (CPAP), and bilevel positive airway pressure (BiPAP) is increasingly used for children with respiratory failure requiring interhospital transport by pediatric critical care transport (PCCT) teams. In this retrospective observational study of children receiving NRS on transport between January 1st, 2017 and December 31st, 2019 by a single PCCT service in England, we describe a cohort of children, looking at patient characteristics, journey logistics, adverse events, and failure of NRS (as defined by emergency intubation on transport or within 24 hours of arriving on the pediatric intensive care unit), and to attempt to identify risk factors that were associated with NRS failure. A total of 3,504 patients were transported during the study period. Three hundred and seventeen (9%) received NRS. Median age was 4.9 months (IQR 1.0–18.2); median weight was 5.1 kg (IQR 3.1–13). The primary diagnostic category was cardiorespiratory in 244/317 (77%) patients. Comorbidities were recorded in 189/317 (59.6%) patients. Median Pediatric Index of Mortality-3 (PIM3) score was 0.024 (IQR 0.012–0.045). Median stabilization time was 80 minutes while median patient journey time was 40 minutes. Nineteen adverse events were described (clinical deterioration, equipment failure/interface issues) affecting 6% of transports. The incidence of NRS failure was 6.6%. No risk factors associated with NRS failure were identified. We concluded that NRS can be considered safe during pediatric transport for children with a wide range of diagnoses and varying clinical severity, with a low rate of adverse events and need for intubation on transport or on the PICU.

Predicting Flow Rate Escalation for Pediatric Patients on High Flow Nasal Cannula Using Machine Learning

Background: High flow nasal cannula (HFNC) is commonly used as non-invasive respiratory support in critically ill children. There are limited data to inform consensus on optimal device parameters, determinants of successful patient response, and indications for escalation of support. Clinical scores, such as the respiratory rate-oxygenation (ROX) index, have been described as a means to predict HFNC non-response, but are limited to evaluating for escalations to invasive mechanical ventilation (MV). In the presence of apparent HFNC non-response, a clinician may choose to increase the HFNC flow rate to hypothetically prevent further respiratory deterioration, transition to an alternative non-invasive interface, or intubation for MV. To date, no models have been assessed to predict subsequent escalations of HFNC flow rates after HFNC initiation. Objective: To evaluate the abilities of tree-based machine learning algorithms to predict HFNC flow rate escalations. Methods: We performed a retrospective, cohort study assessing children admitted for acute respiratory failure under 24 months of age placed on HFNC in the Johns Hopkins Children's Center pediatric intensive care unit from January 2019 through January 2020. We excluded encounters with gaps in recorded clinical data, encounters in which MV treatment occurred prior to HFNC, and cases electively intubated in the operating room. The primary study outcome was discriminatory capacity of generated machine learning algorithms to predict HFNC flow rate escalations as compared to each other and ROX indices using area under the receiver operating characteristic (AUROC) analyses. In an exploratory fashion, model feature importance rankings were assessed by comparing Shapley values. Results: Our gradient boosting model with a time window of 8 h and lead time of 1 h before HFNC flow rate escalation achieved an AUROC with a 95% confidence interval of 0.810 ± 0.003. In comparison, the ROX index achieved an AUROC of 0.525 ± 0.000. Conclusion: In this single-center, retrospective cohort study assessing children under 24 months of age receiving HFNC for acute respiratory failure, tree-based machine learning models outperformed the ROX index in predicting subsequent flow rate escalations. Further validation studies are needed to ensure generalizability for bedside application.

Clinical Factors of High-Flow Nasal Cannula Oxygen Success in Children

This study was aimed to evaluate the success rate of high-flow nasal cannula (HFNC) oxygen therapy and factors causing therapy failure. This prospective observational study included 131 children who received HFNC oxygen and followed-up in the pediatric emergency department, pediatric clinics, and pediatric intensive care unit between March 2018 and December 2019. The median age was 23.0 months (interquartile range [IQR]: 9.0-92.0) and 65 patients were male (49.6%). The most common reason for requiring HFNC oxygen therapy was pneumonia ( n  = 75, 57.3%). A complex chronic condition was present in 112 (85.5%) patients. Therapy success was achieved in 116 patients (88.5%). The reason for requiring treatment and the patients' complex chronic condition did not affect the success of the therapy ( p  = 0.294 and 0.091, respectively). In the first 24 hours of treatment, a significant improvement in pulse rate, respiratory rate, pH, and lactate level were observed in successful HFNC oxygen patients ( p  < 0.05). In addition, these patients showed a significant improvement in SpO ₂ and SpO ₂ /FiO ₂ ratio, and a significant decrease in FiO ₂ and flow rate ( p  < 0.05). HFNC oxygen success rate was 95.6% in patients with SpO ₂ /FiO ₂ ≥ 150 at the 24th hour; it was 58.0% in those with SpO ₂ /FiO ₂  < 150 ( p  < 0.001). Caution should be exercised in terms of HFNC oxygen failure in patients with no significant improvement in vital signs and with SpO ₂ /FiO ₂  < 150 during treatment.

Clinical impact of implementing humidified high-flow nasal cannula on interhospital transport among children admitted to a PICU with respiratory distress: a cohort study

Background

There is a limited evidence for humidified high-flow nasal cannula (HHFNC) use on inter-hospital transport. Despite this, its use during transport is increasing in children with respiratory distress worldwide. In 2015 HHFNC was implemented on a specialized pediatric retrieval team serving for Victoria. The aim of this study is to investigate the effect of the HHFNC implementation on the retrieval team on the paediatric intensive care unit (PICU) length of stay and respiratory support use.

Methods

We performed a cohort study using a comparative interrupted time-series approach controlling for patient and temporal covariates, and population-adjusted analysis. We studied 3022 children admitted to a PICU in Victoria with respiratory distress January 2010–December 2019. Patients were divided in pre-intervention era (2010–2014) and post-intervention era (2015–2019).

Results

1006 children following interhospital transport and 2016 non-transport children were included. Median (IQR) age was 1.4 (0.7–4.5) years. Pneumonia (39.1%) and bronchiolitis (34.3%) were common. On retrieval, HHFNC was used in 5.0% (21/420) and 45.9% (269/586) in pre- and post-intervention era. In an unadjusted model, median (IQR) PICU length of stay was 2.2 (1.1–4.2) and 1.7 (0.9–3.2) days in the pre- and post-intervention era in transported children while the figures were 2.4 (1.3–4.9) and 2.1 (1.2–4.5) days in non-transport children. In the multivariable regression model, the intervention was associated with the reduced PICU length of stay (ratio 0.64, 95% confidential interval 0.49–0.83, p = 0.001) with the predicted reduction of PICU length of stay being − 10.6 h (95% confidential interval − 16.9 to − 4.3 h), and decreased respiratory support use (− 25.1 h, 95% confidential interval − 47.9 to − 2.3 h, p = 0.03). Sensitivity analyses including a model excluding less severe children showed similar results. In population-adjusted analyses, respiratory support use decreased from 4837 to 3477 person-hour per year in transported children over the study era, while the reduction was 594 (from 9553 to 8959) person-hour per year in non-transport children. With regard to the safety, there were no escalations of respiratory support mode during interhospital transport.

Conclusions

The implementation of HHFNC on interhospital transport was associated with the reduced PICU length of stay and respiratory support use among PICU admissions with respiratory distress.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-021-03620-7.

A pediatric high-flow nasal cannula protocol standardizes initial flow and expedites weaning

OBJECTIVE

Respiratory illnesses compose the most common diagnoses of patients admitted to pediatric intensive care units. In pediatrics, high-flow nasal cannula (HFNC) therapy is an intermediate level of respiratory support with variability in practice. We conducted a pre-post intervention study of patients placed on HFNC therapy before and after the implementation of an HFNC protocol.

METHODS

This was a quality improvement/pre-post intervention study of pediatric patients who received HFNC therapy in our teaching, tertiary care children's hospital between January 2015 and April 2019. Patients were evaluated before and after the implementation of a protocol that promoted initiation of higher flow and rapid weaning. Our primary outcomes were initial flow and rate of weaning pre- and post-protocol; our secondary outcomes were HFNC failure rate (defined as escalation to noninvasive ventilation or mechanical ventilation) and length of hospital stay. Propensity matching was used to account for differences in age and weight pre- and post-protocol.

RESULTS

In total, 584 patients were included, 292 pre-protocol, and 292 post-protocol. The median age was 20 months, and the indication for HFNC therapy was bronchiolitis in 29% of patients. Post-protocol patients compared to pre-protocol patients had significantly a higher initial flow (median 14.5 L/min vs. 10 L/min, p < .001) and a higher weaning rate of flow (median 4.1 L/min/h vs. 2.4 L/min/h, p < .001). Post-protocol patients also had a lower HFNC failure rate (10% vs. 17%, p = .015) and a shorter length of stay (5.97 days vs. 6.80 days, p = .006).

CONCLUSION

Among pediatric patients, the implementation of an HFNC protocol increases initial flow, allows for more rapid weaning, and may decrease the incidence of escalation to noninvasive ventilation or mechanical ventilation.

Diagnosis, grading and management of toxicities from immunotherapies in children, adolescents and young adults with cancer

Cancer immunotherapies are associated with remarkable therapeutic response rates but also with unique and severe toxicities, which potentially result in rapid deterioration in health. The number of clinical applications for novel immune effector-cell therapies, including chimeric antigen receptor (CAR)-expressing cells, and other immunotherapies, such as immune-checkpoint inhibitors, is increasing. In this Consensus Statement, members of the Pediatric Acute Lung Injury and Sepsis Investigators (PALISI) Network Hematopoietic Cell Transplantation-Cancer Immunotherapy (HCT-CI) Subgroup, Paediatric Diseases Working Party (PDWP) of the European Society of Blood and Marrow Transplantation (EBMT), Supportive Care Committee of the Pediatric Transplantation and Cellular Therapy Consortium (PTCTC) and MD Anderson Cancer Center CAR T Cell Therapy-Associated Toxicity (CARTOX) Program collaborated to provide updated comprehensive recommendations for the care of children, adolescents and young adults receiving cancer immunotherapies. With these recommendations, we address emerging toxicity mitigation strategies, we advocate for the characterization of baseline organ function according to age and discipline-specific criteria, we recommend early critical care assessment when indicated, with consideration of reversibility of underlying pathology (instead of organ failure scores) to guide critical care interventions, and we call for researchers, regulatory agencies and sponsors to support and facilitate early inclusion of young patients with cancer in well-designed clinical trials.

Predicting Failure of Non-Invasive Ventilation With RAM Cannula in Bronchiolitis

INTRODUCTION

In infants hospitalized for bronchiolitis on non-invasive ventilation (NIV) via the RAM cannula nasal interface, variables predicting subsequent intubation, or NIV non-response, are understudied. We sought to identify predictors of NIV non-response.

METHODS

We performed a retrospective cohort study in infants admitted for respiratory failure from bronchiolitis placed on NIV in a quaternary children's hospital. We excluded children with concurrent sepsis, critical congenital heart disease, or with preexisting tracheostomy. The primary outcome was NIV non-response defined as intubation after a trial of NIV. Secondary outcomes were vital sign values before and after NIV initiation, duration of NIV and intubation, and mortality. Primary analyses included Chi-square, Wilcoxon rank-sum, student's t test, paired analyses, and adjusted and unadjusted logistic regression assessing heart rate (HR) and respiratory rate (RR) before and after NIV initiation.

RESULTS

Of 138 infants studied, 34% were non-responders. There were no differences in baseline characteristics of responders and non-responders. HR decreased after NIV initiation in responders (156 [143-156] to149 [141-158], p < 0.01) compared to non-responders (158 [149-166] to 158 [145-171], p = 0.73). RR decreased in responders (50 [43-58] vs 47 [41-54]) and non-responders (52 [48-58] vs 51 [40-55], both p < 0.01). Concurrent bacterial pneumonia (OR 6.06, 95% CI: 2.54-14.51) and persistently elevated HR (OR: 1.04, 95% CI: 1.01-1.07) were associated with NIV non-response.

CONCLUSION

In children with acute bronchiolitis who fail to respond to NIV and require subsequent intubation, we noted associations with persistently elevated HR after NIV initiation and concurrent bacterial pneumonia.

Physiometric Response to High-Flow Nasal Cannula Support in Acute Bronchiolitis

OBJECTIVES

To describe the rate of high-flow nasal cannula (HFNC) nonresponse and paired physiometric responses (changes [∆] in heart rate [HR] and respiratory rate [RR]) before and after HFNC initiation in hospitalized children with bronchiolitis.

METHODS

We performed a single-center, prospective descriptive study in a PICU within a quaternary referral center, assessing children aged ≤2 years admitted for bronchiolitis on HFNC from November 2017 to March 2020. We excluded for cystic fibrosis, airway anomalies, pulmonary hypertension, tracheostomy, neuromuscular disease, congenital heart disease, or preadmission intubation. Primary outcomes were paired ∆ and %∆ in HR and RR before and after HFNC initiation. Secondary outcomes were HFNC nonresponse rate (ie, intubation or transition to noninvasive positive pressure ventilation). Analyses included χ², Student's t, Wilcoxon rank, and paired testing.

RESULTS

Of the 172 children studied, 56 (32.6%) experienced HFNC nonresponse at a median of 14.4 (interquartile range: 4.8-36) hours and 11 (6.4%) were intubated. Nonresponders had a greater frequency of bacterial pneumonia, but otherwise no major differences in demographics, comorbidities, or viral pathogens were noted. Responders experienced reductions in both %ΔRR (-17.1% ± 15.8% vs +5.3% ± 22.3%) and %ΔHR (-6.5% ± 10.5% vs 0% ± 10.9%) compared with nonresponders.

CONCLUSIONS

In this prospective, observational cohort study, we provide baseline data describing expected physiologic changes after initiation of HFNC for children admitted to the PICU for bronchiolitis. In our descriptive analysis, patients with comorbid bacterial pneumonia appear to be at additional risk for subsequent HFNC nonresponse.

[Efficacy of high-flow nasal cannula versus nasal continuous positive airway pressure in the treatment of respiratory distress syndrome in neonates: a Meta analysis]

OBJECTIVE

To systematically evaluate the efficacy and safety of high-flow nasal cannula (HFNC) therapy versus nasal continuous positive airway pressure (nCPAP) in the treatment of respiratory distress syndrome (RDS) in neonates.

METHODS

PubMed, Embase, Cochrane Library, Web of Science, China Biology Medicine disc, Wanfang Database, CNKI, and Weipu Database were searched for the randomized controlled trials (RCTs) of HFNC versus nCPAP in the treatment of neonatal RDS published up to April 1, 2020. RevMan5.3 software was used to perform a Meta analysis of the eligible RCTs.

RESULTS

A total of 12 RCTs were included, with 2 861 neonates in total, among whom 2 698 neonates (94.30%) had a gestational age of ≥28 weeks and 163 (5.70%) had a gestational age of <28 weeks. For primary respiratory support, the HFNC group had a significantly higher rate of treatment failure than the nCPAP group (RR=1.86, 95%CI: 1.53-2.25, P<0.001), but there were no significant differences between the two groups in the rate of invasive mechanical ventilation (P=0.40) and the rate of use of pulmonary surfactant (P=0.77). For post-extubation respiratory support, there were no significant differences between the two groups in the treatment failure rate, reintubation rate, and total oxygen supply time (P>0.05). For primary respiratory support and post-extubation respiratory support, the HFNC group had a significantly lower incidence rate of nasal injury than the nCPAP group (P<0.001), and there were no significant differences between the two groups in the mortality rate and incidence rates of the complications such as air leak syndrome, bronchopulmonary dysplasia, and necrotizing enterocolitis (P>0.05).

CONCLUSIONS

Based on the current clinical evidence, HFNC has a higher failure rate than nCPAP when used as primary respiratory support for neonates with RDS, and therefore it is not recommended to use HFNC as the primary respiratory support for neonates with RDS. In RDS neonates with a gestational age of ≥28 weeks, HFNC can be used as post-extubation respiratory support in the weaning phase.

First-line support for assistance in breathing in children: statistical and health economic analysis plan for the FIRST-ABC trial

Background

The FIRST-ABC trial comprises of two pragmatic, multicentre, parallel groups, non-inferiority randomised clinical trials designed to evaluate the clinical non-inferiority of first-line use of high flow nasal cannula (HFNC) to continuous positive airway pressure (CPAP) in critically ill children who require non-invasive respiratory support (NRS).

Objectives

To describe the pre-specified statistical and health economic analysis for the FIRST-ABC trial before completion of patient recruitment and data collection.

Methods

The statistical analysis plan was designed by the chief investigators and statisticians. We define the primary and secondary outcomes, summarise methods for data collection and safety monitoring, and present a detailed description of the planned statistical and health economic analysis.

Results

The primary clinical outcome is time to liberation from respiratory support. The primary effect estimate will be the adjusted hazard ratio, reported with a 95% confidence interval. As a sensitivity analysis, the primary analysis will be repeated using time to start weaning of NRS. Subgroup analyses will be performed to test for interactions between the effect of allocated treatment group and pre-specified baseline covariates. The health economic analysis will follow the intention-to-treat principle and report the mean (95% confidence interval) incremental costs, quality-adjusted life years (QALYs) and cost-effectiveness up to 6 months. All analyses will be performed separately for each of the two trials, and any results will not be combined.

Conclusion

The FIRST-ABC trial will assess the non-inferiority of HFNC compared to CPAP in two parallel trials with shared infrastructure (step-up RCT and step-down RCT). We have developed a pre-specified statistical and health economics analysis plan for the FIRST-ABC study before trial completion to minimise analytical bias.

Trial registration

ISRCTN ISRCTN60048867. Registered on 19 June 2019.

FIRST-line support for assistance in breathing in children (FIRST-ABC): a master protocol of two randomised trials to evaluate the non-inferiority of high-flow nasal cannula (HFNC) versus continuous positive airway pressure (CPAP) for non-invasive respiratory support in paediatric critical care

INTRODUCTION

Even though respiratory support is a common intervention in paediatric critical care, there is no randomised controlled trial (RCT) evidence regarding the effectiveness of two commonly used modes of non-invasive respiratory support (NRS), continuous positive airway pressure (CPAP) and high-flow nasal cannula therapy (HFNC). FIRST-line support for assistance in breathing in children is a master protocol of two pragmatic non-inferiority RCTs to evaluate the clinical and cost-effectiveness of HFNC (compared with CPAP) as the first-line mode of support in critically ill children.

METHODS AND ANALYSIS

We will recruit participants over a 30-month period at 25 UK paediatric critical care units (paediatric intensive care units/high-dependency units). Patients are eligible if admitted/accepted for admission, aged >36 weeks corrected gestational age and <16 years, and assessed by the treating clinician to require NRS for an acute illness (step-up RCT) or within 72 hours of extubation following a period of invasive ventilation (step-down RCT). Due to the emergency nature of the treatment, written informed consent will be deferred to after randomisation. Randomisation will occur 1:1 to CPAP or HFNC, stratified by site and age (<12 vs ≥12 months). The primary outcome is time to liberation from respiratory support for a continuous period of 48 hours. A total sample size of 600 patients in each RCT will provide 90% power with a type I error rate of 2.5% (one sided) to exclude the prespecified non-inferiority margin of HR of 0.75. Primary analyses will be undertaken separately in each RCT in both the intention-to-treat and per-protocol populations.

ETHICS AND DISSEMINATION

This master protocol received favourable ethical opinion from National Health Service East of England-Cambridge South Research Ethics Committee (reference: 19/EE/0185) and approval from the Health Research Authority (reference: 260536). Results will be disseminated via publications in peer-reviewed medical journals and presentations at national and international conferences.

TRIAL REGISTRATION NUMBER

ISRCTN60048867.

Predicting use of high-flow nasal cannula therapy following extubation in paediatrics

BACKGROUND

High-flow nasal cannula (HFNC) therapy is widely used for respiratory support within paediatrics, most commonly used as a supportive measure in acute respiratory failure, aiming to avoid invasive mechanical ventilation (IMV). It is increasingly being used following extubation of critically ill children potentially at a higher risk of requiring re-intubation. Less data indicate the use for post-extubation HFNC therapy or possible clinical outcomes of this therapy.

AIMS AND OBJECTIVES

To identify reasons for, and variables to predict, the use of HFNC therapy post-extubation.

DESIGN

This was a retrospective case-control study.

METHODS

All children admitted to a nine-bedded regional paediatric intensive care unit requiring IMV between 18 December 2017 and 28 November 2018 were identified. The demographic data and bedside clinical and laboratory variables of the patients requiring HFNC therapy were compared with those who did not require HFNC.

RESULTS

There was no statistical difference in the median age and weight of children receiving HFNC therapy post-extubation compared with children not receiving it. In a logistic regression model, the highest ventilation (peak inspiratory pressure) and oxygen requirements in the first 24 hours of admission, along with the presence of comorbidity and use of HFNC therapy prior to intubation, predicted the use of HFNC following extubation, (r² 0.42, area under the receiver operating curve 0.843, P < .0001).

CONCLUSIONS

The direct correlation between high initial ventilatory requirements and pre-existing comorbidity was significant for the use of post-extubation HFNC therapy. This may be useful to stratify children in the use of HFNC therapy post-extubation in the critically ill population.

RELEVANCE TO CLINICAL PRACTICE

This study provides evidence that it may be possible to predict the use of HFNC therapy post-extubation. Avoiding unnecessary use of this therapy improves patient care while providing a positive economic impact.

Efficacy of High-Flow Nasal Cannula vs Standard Oxygen Therapy or Nasal Continuous Positive Airway Pressure in Children with Respiratory Distress: A Meta-Analysis

OBJECTIVES

To evaluate the efficacy of high-flow nasal cannula (HFNC) oxygen therapy in providing respiratory support of children with acute lower respiratory infection (ALRI), hypoxemia, and respiratory distress.

STUDY DESIGN

We performed a meta-analysis of randomized controlled trials that compared HFNC and standard flow oxygen therapy or nasal continuous positive airway pressure (nCPAP) and reported treatment failure as an outcome. Data were synthesized using Mann-Whitney U test.

RESULTS

Compared with standard oxygen therapy, HFNC significantly reduced treatment failure (risk ratio [RR] 0.49, 95% CI 0.40-0.60, P < .001) in children with mild hypoxemia (arterial pulse oximetry [SpO₂] >90% on room air). HFNC had an increased risk of treatment failure compared with nCPAP in infants age 1-6 months with severe hypoxemia (SpO₂ <90% on room air or SpO₂ >90% on supplemental oxygen) (RR 1.77, 95% CI 1.17-2.67, P = .007). No significant differences were found in intubation rates and mortality between HFNC and standard oxygen therapy or nCPAP. HFNC had a lower risk of nasal trauma compared with nCPAP (RR 0.35, 95% CI 0.16-0.77, P = .009).

CONCLUSIONS

Among children <5 years of age with ALRI, respiratory distress, and mild hypoxemia, HFNC reduced the risk of treatment failure when compared with standard oxygen therapy. However, nCPAP was associated with a lower risk of treatment failure than HFNC in infants age 1-6 months with ALRI, moderate-to-severe respiratory distress, and severe hypoxemia. No differences were found in intubation and mortality between HFNC and standard oxygen therapy or nCPAP.