High-flow nasal cannula as a device to provide continuous positive airway pressure in infants

High-flow nasal cannula therapy for infants with bronchiolitis

BACKGROUND

Bronchiolitis is a common lower respiratory tract illness, usually of viral aetiology, affecting infants younger than 24 months of age and is the most common cause of hospitalisation of infants. It causes airway inflammation, mucus production and mucous plugging, resulting in airway obstruction. Effective pharmacotherapy is lacking and bronchiolitis is a major cause of morbidity and mortality. Conventional treatment consists of supportive therapy in the form of fluids, supplemental oxygen, and respiratory support. Traditionally, oxygen delivery is as a dry gas at 100% concentration via low-flow nasal prongs. However, the use of heated, humidified, high-flow nasal cannula (HFNC) therapy enables delivery of higher inspired gas flows of an air/oxygen blend, at 2 to 3 L/kg per minute up to 60 L/min in children. It can provide some level of continuous positive airway pressure (CPAP) to improve ventilation in a minimally invasive manner. This may reduce the need for invasive respiratory support, thus potentially lowering costs, with clinical advantages and fewer adverse effects.

OBJECTIVES

To assess the effects of HFNC therapy compared with conventional respiratory support in the treatment of infants with bronchiolitis.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, CINAHL, LILACS, and Web of Science (from June 2013 to December 2022). In addition, we consulted ongoing trial registers and experts in the field to identify ongoing studies, checked reference lists of relevant articles, and searched for conference abstracts. Date restrictions were imposed such that we only searched for studies published after the original version of this review.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) or quasi-RCTs that assessed the effects of HFNC (delivering oxygen or oxygen/room air blend at flow rates greater than 4 L/minute) compared to conventional treatment in infants (< 24 months) with a clinical diagnosis of bronchiolitis.

DATA COLLECTION AND ANALYSIS

Two review authors independently used a standard template to assess trials for inclusion and extract data on study characteristics, risk of bias elements, and outcomes. We contacted trial authors to request missing data. Outcome measures included the need for invasive respiratory support and time until discharge, clinical severity measures, oxygen saturation, duration of oxygen therapy, and adverse events.

MAIN RESULTS

In this update we included 15 new RCTs (2794 participants), bringing the total number of RCTs to 16 (2813 participants). Of the 16 studies, 11 compared high-flow to low-flow, and five compared high-flow to CPAP. These studies included infants less than 24 months of age as stated in our selection criteria. There were no significant differences in sex. We found that when comparing high-flow to low-flow oxygen therapy for infants with bronchiolitis there may be a reduction in the total length of hospital stay (mean difference (MD) -0.65 days, 95% confidence interval (CI) -1.23 to -0.06; P < 0.00001, I2 = 89%; 7 studies, 1951 participants; low-certainty evidence). There may also be a reduction in the duration of oxygen therapy (MD -0.59 days, 95% CI -1 to -0.18; P < 0.00001, I2 = 86%; 7 studies, 2132 participants; low-certainty evidence). We also found that there was probably an improvement in respiratory rate at one and 24 hours, and heart rate at one, four to six, and 24 hours in those receiving high-flow oxygen therapy when compared to pre-intervention baselines. There was also probably a reduced risk of treatment escalation in those receiving high-flow when compared to low-flow oxygen therapy (risk ratio (RR) 0.55, 95% CI 0.39 to 0.79; P = 0.001, I2 = 43%; 8 studies, 2215 participants; moderate-certainty evidence). We found no difference in the incidence of adverse events (RR 1.2, 95% CI 0.38 to 3.74; P = 0.76, I2 = 26%; 4 studies, 1789 participants; low-certainty evidence) between the two groups. The lack of comparable outcomes in studies comparing high-flow and CPAP, as well as the small numbers of participants, limited our ability to perform meta-analysis on this group.

AUTHORS' CONCLUSIONS

High-flow nasal cannula therapy may have some benefits over low-flow oxygen for infants with bronchiolitis in terms of a greater improvement in respiratory and heart rates, as well as a modest reduction in the length of hospital stay and duration of oxygen therapy, with a reduced incidence of treatment escalation. There does not appear to be a difference in the number of adverse events. Further studies comparing high-flow nasal cannula therapy and CPAP are required to demonstrate the efficacy of one modality over the other. A standardised clinical definition of bronchiolitis, as well as the use of a validated clinical severity score, would allow for greater and more accurate comparison between studies.

Guidelines for high-flow nasal cannula oxygen therapy in neonates (2022)

High-flow nasal cannula (HFNC) oxygen therapy, which is important in noninvasive respiratory support, is increasingly being used in critically ill neonates with respiratory failure because it is comfortable, easy to setup, and has a low incidence of nasal trauma. The advantages, indications, and risks of HFNC have been the focus of research in recent years, resulting in the development of the application. Based on current evidence, we developed guidelines for HFNC in neonates using the Grading of Recommendations Assessment, Development and Evaluation (GRADE). The guidelines were formulated after extensive consultations with neonatologists, respiratory therapists, nurse specialists, and evidence-based medicine experts. We have proposed 24 recommendations for 9 key questions. The guidelines aim to be a source of evidence and reference of HFNC oxygen therapy in clinical practice, and so that more neonates and their families will benefit from HFNC.

High flow nasal cannula for respiratory support in term infants

BACKGROUND

Respiratory failure or respiratory distress in infants is the most common reason for non-elective admission to hospitals and neonatal intensive care units. Non-invasive methods of respiratory support have become the preferred mode of treating respiratory problems as they avoid some of the complications associated with intubation and mechanical ventilation. High flow nasal cannula (HFNC) therapy is increasingly being used as a method of non-invasive respiratory support. However, the evidence pertaining to its use in term infants (defined as infants ≥ 37 weeks gestational age to the end of the neonatal period (up to one month postnatal age)) is limited and there is no consensus of opinion regarding the safety and efficacy HFNC in this population.

OBJECTIVES

To assess the safety and efficacy of high flow nasal cannula oxygen therapy for respiratory support in term infants when compared with other forms of non-invasive respiratory support.

SEARCH METHODS

We searched the following databases in December 2022: Cochrane CENTRAL; PubMed; Embase; CINAHL; LILACS; Web of Science; Scopus. We also searched the reference lists of retrieved studies and performed a supplementary search of Google Scholar.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that investigated the use of high flow nasal cannula oxygen therapy in infants ≥ 37 weeks gestational age up to one month postnatal age (the end of the neonatal period).

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial eligibility, performed data extraction, and assessed risk of bias in the included studies. Where studies were sufficiently similar, we performed a meta-analysis using mean differences (MD) for continuous data and risk ratios (RR) for dichotomous data, with their respective 95% confidence intervals (CIs). For statistically significant RRs, we calculated the number needed to treat for an additional beneficial outcome (NNTB). We used the GRADE approach to evaluate the certainty of the evidence for clinically important outcomes.

MAIN RESULTS

We included eight studies (654 participants) in this review. Six of these studies (625 participants) contributed data to our primary analyses. Four studies contributed to our comparison of high flow nasal cannula (HFNC) oxygen therapy versus continuous positive airway pressure (CPAP) for respiratory support in term infants. The outcome of death was reported in two studies (439 infants) but there were no events in either group. HFNC may have little to no effect on treatment failure, but the evidence is very uncertain (RR 0.98, 95% CI 0.47 to 2.04; 3 trials, 452 infants; very low-certainty evidence). The outcome of chronic lung disease (need for supplemental oxygen at 28 days of life) was reported in one study (375 participants) but there were no events in either group. HFNC may have little to no effect on the duration of respiratory support (any form of non-invasive respiratory support with or without supplemental oxygen), but the evidence is very uncertain (MD 0.17 days, 95% CI -0.28 to 0.61; 4 trials, 530 infants; very low-certainty evidence). HFNC likely results in little to no difference in the length of stay at the intensive care unit (ICU) (MD 0.90 days, 95% CI -0.31 to 2.12; 3 trials, 452 infants; moderate-certainty evidence). HFNC may reduce the incidence of nasal trauma (RR 0.16, 95% CI 0.04 to 0.66; 1 trial, 78 infants; very low-certainty evidence) and abdominal overdistension (RR 0.22, 95% CI 0.07 to 0.71; 1 trial, 78 infants; very low-certainty evidence), but the evidence is very uncertain. Two studies contributed to our analysis of HFNC versus low flow nasal cannula oxygen therapy (LFNC) (supplemental oxygen up to a maximum flow rate of 2 L/min). The outcome of death was reported in both studies (95 infants) but there were no events in either group. The evidence suggests that HFNC may reduce treatment failure slightly (RR 0.44, 95% CI 0.21 to 0.92; 2 trials, 95 infants; low-certainty evidence). Neither study reported results for the outcome of chronic lung disease (need for supplemental oxygen at 28 days of life). HFNC may have little to no effect on the duration of respiratory support (MD -0.07 days, 95% CI -0.83 to 0.69; 1 trial, 74 infants; very low-certainty evidence), length of stay at the ICU (MD 0.49 days, 95% CI -0.83 to 1.81; 1 trial, 74 infants; very low-certainty evidence), or hospital length of stay (MD -0.60 days, 95% CI -2.07 to 0.86; 2 trials, 95 infants; very low-certainty evidence), but the evidence is very uncertain. Adverse events was an outcome reported in both studies (95 infants) but there were no events in either group. The risk of bias across outcomes was generally low, although there were some concerns of bias. The certainty of evidence across outcomes ranged from moderate to very low, downgraded due to risk of bias, imprecision, indirectness, and inconsistency.

AUTHORS' CONCLUSIONS

When compared with CPAP, HFNC may result in little to no difference in treatment failure. HFNC may have little to no effect on the duration of respiratory support, but the evidence is very uncertain. HFNC likely results in little to no difference in the length of stay at the intensive care unit. HFNC may reduce the incidence of nasal trauma and abdominal overdistension, but the evidence is very uncertain. When compared with LFNC, HFNC may reduce treatment failure slightly. HFNC may have little to no effect on the duration of respiratory support, length of stay at the ICU, or hospital length of stay, but the evidence is very uncertain. There is insufficient evidence to enable the formulation of evidence-based guidelines on the use of HFNC for respiratory support in term infants. Larger, methodologically robust trials are required to further evaluate the possible health benefits or harms of HFNC in this patient population.

Nasal high flow therapy for primary respiratory support in preterm infants

BACKGROUND

Nasal high flow (nHF) therapy provides heated, humidified air and oxygen via two small nasal prongs, at gas flows of more than 1 litre/minute (L/min), typically 2 L/min to 8 L/min. nHF is commonly used for non-invasive respiratory support in preterm neonates. It may be used in this population for primary respiratory support (avoiding, or prior to the use of mechanical ventilation via an endotracheal tube) for prophylaxis or treatment of respiratory distress syndrome (RDS). This is an update of a review first published in 2011 and updated in 2016.

OBJECTIVES

To evaluate the benefits and harms of nHF for primary respiratory support in preterm infants compared to other forms of non-invasive respiratory support.

SEARCH METHODS

We used standard, extensive Cochrane search methods. The latest search date March 2022.

SELECTION CRITERIA

We included randomised or quasi-randomised trials comparing nHF with other forms of non-invasive respiratory support for preterm infants born less than 37 weeks' gestation with respiratory distress soon after birth.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane Neonatal methods. Our primary outcomes were 1. death (before hospital discharge) or bronchopulmonary dysplasia (BPD), 2. death (before hospital discharge), 3. BPD, 4. treatment failure within 72 hours of trial entry and 5. mechanical ventilation via an endotracheal tube within 72 hours of trial entry. Our secondary outcomes were 6. respiratory support, 7. complications and 8. neurosensory outcomes. We used GRADE to assess the certainty of evidence.

MAIN RESULTS

We included 13 studies (2540 infants) in this updated review. There are nine studies awaiting classification and 13 ongoing studies. The included studies differed in the comparator treatment (continuous positive airway pressure (CPAP) or nasal intermittent positive pressure ventilation (NIPPV)), the devices for delivering nHF and the gas flows used. Some studies allowed the use of 'rescue' CPAP in the event of nHF treatment failure, prior to any mechanical ventilation, and some allowed surfactant administration via the INSURE (INtubation, SURfactant, Extubation) technique without this being deemed treatment failure. The studies included very few extremely preterm infants less than 28 weeks' gestation. Several studies had unclear or high risk of bias in one or more domains. Nasal high flow compared with continuous positive airway pressure for primary respiratory support in preterm infants Eleven studies compared nHF with CPAP for primary respiratory support in preterm infants. When compared with CPAP, nHF may result in little to no difference in the combined outcome of death or BPD (risk ratio (RR) 1.09, 95% confidence interval (CI) 0.74 to 1.60; risk difference (RD) 0, 95% CI -0.02 to 0.02; 7 studies, 1830 infants; low-certainty evidence). Compared with CPAP, nHF may result in little to no difference in the risk of death (RR 0.78, 95% CI 0.44 to 1.39; 9 studies, 2009 infants; low-certainty evidence), or BPD (RR 1.14, 95% CI 0.74 to 1.76; 8 studies, 1917 infants; low-certainty evidence). nHF likely results in an increase in treatment failure within 72 hours of trial entry (RR 1.70, 95% CI 1.41 to 2.06; RD 0.09, 95% CI 0.06 to 0.12; number needed to treat for an additional harmful outcome (NNTH) 11, 95% CI 8 to 17; 9 studies, 2042 infants; moderate-certainty evidence). However, nHF likely does not increase the rate of mechanical ventilation (RR 1.04, 95% CI 0.82 to 1.31; 9 studies, 2042 infants; moderate-certainty evidence). nHF likely results in a reduction in pneumothorax (RR 0.66, 95% CI 0.40 to 1.08; 10 studies, 2094 infants; moderate-certainty evidence) and nasal trauma (RR 0.49, 95% CI 0.36 to 0.68; RD -0.06, 95% CI -0.09 to -0.04; 7 studies, 1595 infants; moderate-certainty evidence). Nasal high flow compared with nasal intermittent positive pressure ventilation for primary respiratory support in preterm infants Four studies compared nHF with NIPPV for primary respiratory support in preterm infants. When compared with NIPPV, nHF may result in little to no difference in the combined outcome of death or BPD, but the evidence is very uncertain (RR 0.64, 95% CI 0.30 to 1.37; RD -0.05, 95% CI -0.14 to 0.04; 2 studies, 182 infants; very low-certainty evidence). nHF may result in little to no difference in the risk of death (RR 0.78, 95% CI 0.36 to 1.69; RD -0.02, 95% CI -0.10 to 0.05; 3 studies, 254 infants; low-certainty evidence). nHF likely results in little to no difference in the incidence of treatment failure within 72 hours of trial entry compared with NIPPV (RR 1.27, 95% CI 0.90 to 1.79; 4 studies, 343 infants; moderate-certainty evidence), or mechanical ventilation within 72 hours of trial entry (RR 0.91, 95% CI 0.62 to 1.33; 4 studies, 343 infants; moderate-certainty evidence). nHF likely results in a reduction in nasal trauma, compared with NIPPV (RR 0.21, 95% CI 0.09 to 0.47; RD -0.17, 95% CI -0.24 to -0.10; 3 studies, 272 infants; moderate-certainty evidence). nHF likely results in little to no difference in the rate of pneumothorax (RR 0.78, 95% CI 0.40 to 1.53; 4 studies, 344 infants; moderate-certainty evidence). Nasal high flow compared with ambient oxygen We found no studies examining this comparison. Nasal high flow compared with low flow nasal cannulae We found no studies examining this comparison.

AUTHORS' CONCLUSIONS

The use of nHF for primary respiratory support in preterm infants of 28 weeks' gestation or greater may result in little to no difference in death or BPD, compared with CPAP or NIPPV. nHF likely results in an increase in treatment failure within 72 hours of trial entry compared with CPAP; however, it likely does not increase the rate of mechanical ventilation. Compared with CPAP, nHF use likely results in less nasal trauma and likely a reduction in pneumothorax. As few extremely preterm infants less than 28 weeks' gestation were enrolled in the included trials, evidence is lacking for the use of nHF for primary respiratory support in this population.

Heated humidified high flow nasal cannula therapy in children with obstructive sleep apnea: A randomized cross-over trial

OBJECTIVE/BACKGROUND

Moderate-to-severe obstructive sleep apnea (OSA) is highly prevalent in children with obesity and/or underlying medical complexity. The first line of therapy, adenotonsillectomy (AT), does not cure OSA in more than 50% of these children. Consequently, continuous positive airway pressure (CPAP) is the main therapeutic option but adherence is often poor. A potential alternative which may be associated with greater adherence is heated high-flow nasal cannula (HFNC) therapy; however, its efficacy in children with OSA has not been systematically investigated. The study aimed to compare the efficacy of HFNC with CPAP to treat moderate-to-severe OSA with the primary outcome measuring the change from baseline in the mean obstructive apnea/hypopnea index (OAHI).

PARTICIPANTS/METHODS

This was a single-blinded randomized, two period crossover trial conducted from March 2019 to December 2021 at a Canadian pediatric quaternary care hospital. Children aged 2-18 years with obesity and medical complexity diagnosed with moderate-to-severe OSA via overnight polysomnography and recommended CPAP therapy were included in the study. Following diagnostic polysomnography, each participant completed two further sleep studies; a HFNC titration study and a CPAP titration study (9 received HFNC first, and 9 received CPAP first) in a random 1:1 allocation order.

RESULTS

Eighteen participants with a mean ± SD age of 11.9 ± 3.8 years and OAHI 23.1 ± 21.7 events/hour completed the study. The mean [95% CI] reductions in OAHI (-19.8[-29.2, -10.5] vs. -18.8 [-28.2, -9.4] events/hour, p = 0.9), nadir oxygen saturation (7.1[2.2, 11.9] vs. 8.4[3.5, 13.2], p = 0.8), oxygen desaturation index (-11.6[-21.0, -2.3] vs. -16.0[-25.3, -6.6], p = 0.5) and sleep efficiency (3.5[-4.8, 11.8] vs. 9.2[0.9, 15.5], p = 0.2) with HFNC and CPAP therapy were comparable between conditions.

CONCLUSION

HFNC and CPAP therapy yield similar reductions in polysomnography quantified measures of OSA severity among children with obesity and medical complexities.

TRIAL REGISTRATION

NCT05354401 ClinicalTrials.gov.

Effect of flow rate on the end-expiratory lung volume in infants with bronchiolitis using high-flow nasal cannula evaluated through electrical impedance tomography

OBJECTIVES

To evaluate the effects of four flow rates on the functional residual capacity (FRC) and pulmonary ventilation distribution while using a high-flow nasal cannula (HFNC).

WORKING HYPOTHESIS

Our hypothesis is that flow rates below 1.5 L·kg^-1 ·min^-1 lead to FRC loss and respiratory distress.

STUDY DESIGN

A single-center, prospective clinical study.

PATIENT SELECTION

Infants diagnosed with acute viral bronchiolitis were given HFNC.

METHODOLOGY

Through a prospective clinical study, the effects of four different flow rates, 2.0, 1.5, 1.0, and 0.5 L·kg^-1 ·min^-1 , on FRC and the pulmonary ventilation pattern were evaluated using electrical impedance tomography. The impedance variation (delta Z), end-expiratory lung volume (EELZ), respiratory rate, heart rate, respiratory distress score, and saturation/fraction of inspired oxygen ratio (SpO₂ /F_I O₂ ), were also evaluated at each flow rate.

RESULTS

Among the 11 infants included, There was a decrease in respiratory distress score at a flow rate of 1.5 L·kg^-1 ·min^-1 (*p = 0.021), and at a flow rate of 2.0 L·kg^-1 ·min^-1 (**p = 0.003) compared to 0.5 L·kg^-1 ·min^-1 . There was also a small but significant increase in SpO₂ /FiO₂ at flow rates of 1.5 (*p = 0.023), and 2.0 L·kg^-1 ·min^-1 (**p = 0.008) compared to 0.5 L·kg^-1 ·min^-1 . There were no other significant changes in the clinical parameters. In the global EELZ measurements, there was a significant increase under a flow rate of 2.0 L·kg^-1 ·min^-1 as compared to 0.5 L·kg^-1 ·min^-1 (p = 0.03). In delta Z values, there were no significant variations between the different flow rates.

CONCLUSION

The ∆EELZ increases at the highest flow rates were accompanied by decreased distress scores and improved oxygenation.

Factors associated with failure of using high flow nasal cannula in children

INTRODUCTION

High flow nasal cannula (HFNC) has significantly success in treating acute respiratory distress while HFNC failure dramatically increases mortality and morbidity.

OBJECTIVE

To describe factors associated with failure of HFNC use in children.

METHODS

We performed a retrospective observational study using demographic and laboratory findings. We compared clinical and laboratory variables in both successful and failed HFNC groups. The correlations between factors and HFNC failure were constructed by binary logistic regression analysis.

RESULTS

Between August 2016 and May 2018, 250 children receiving HFNC (median age 16 months; range 1-228 months, male 50.8%) were enrolled. Pneumonia was the most common cause of respiratory distress, and the median length of stay (LOS) in hospital was 11 days. HFNC failure was found 16.4% while HFNC complication was 4.8% including epistaxis, pressure sore, and gastric distension. Based on multivariable logistic regression analysis, factors associated with HFNC failure were children with congenital heart disease comorbidity (p = 0.005), HFNC use with maximum FiO₂  > 0.6 (p = 0.021), lobar infiltration on chest X-ray (p = 0.012), the reduction of heart rate, and respiratory rate <20% after 1 h of HFNC use (p = 0.001 and p = 0.001, respectively).

CONCLUSION

HFNC is feasible to use for children with respiratory distress; however, patients with congenital heart disease, using HFNC with FiO₂  > 0.6, lobar infiltration on chest X-ray should be closely monitored. Heart rate and respiratory rate are important parameters in addition to clinical assessment for evaluating HFNC failure in children.

Use of high-flow nasal oxygen in spontaneously breathing pediatric patients undergoing tubeless airway surgery: A prospective observational study

The use of high-flow nasal oxygen is gaining popularity in apneic and spontaneously breathing adult patients during anesthesia. This prospective observational study evaluated the effect of high-flow nasal oxygen in maintaining adequate oxygenation and ventilation in spontaneously breathing pediatric patients with dynamic airway obstruction, undergoing tubeless airway surgery. Oxygenation was provided via an age-appropriate, high-flow nasal cannula at a flow rate of 2 L kg-1 min-1. Propofol and remifentanil were used to maintain anesthesia while preserving spontaneous respiration. We sought to determine the incidence and risk factors of rescue ventilation. Rescue ventilation with a face mask was performed when the pulse oximetry oxygen saturation was <90% or transcutaneous carbon dioxide was >80 mm Hg. In total, 27 patients were included in the final analysis. Median (interquartile range) of pulse oximetry and transcutaneous carbon dioxide were 100% (99%-100%) and 58.4 mm Hg (51.4-70.3 mm Hg), respectively. Altogether, 9 (33.3%) patients needed rescue ventilation during anesthesia. Of these, 7 patients (25.9%) developed oxygen desaturation (<90%) and 2 patients (7.4%) developed hypercarbia. Patients who required rescue ventilation were significantly younger (8.2 vs 28.8 months, P = .02) and required a longer anesthesia time (55.7 vs 41.0 minutes, P = .04) than those who did not. In conclusion, High-flow nasal oxygen is an alternative technique to maintain oxygenation in children undergoing airway surgeries. However, younger age and longer anesthesia time are significant risk factors leading to the requirement of rescue ventilation in these patients. Further studies with large sample size are required for clinical application of these techniques.

Safe in the first attempt: teaching neonatal airway management

PURPOSE OF REVIEW

Quick and precise facemask ventilation and tracheal intubation are critical clinical skills in neonatal airway management. In addition, this vulnerable population requires a thorough understanding of developmental airway anatomy and respiratory physiology to manage and anticipate potential airway mishaps. Neonates have greater oxygen consumption, increased minute ventilation relative to functional residual capacity, and increased closing volumes compared to older children and adults. After a missed airway attempt, this combination can quickly lead to dire consequences, such as cardiac arrest. Keeping neonates safe throughout the first attempt of airway management is key.

RECENT FINDINGS

Several techniques and practices have evolved to improve neonatal airway management, including improvement in neonatal airway equipment, provision of passive oxygenation, and closer attention to the management of anesthetic depth. The role of nontechnical skills during airway management is receiving more recognition.

SUMMARY

Every neonatal intubation should be considered a critical event. Below we discuss some of the challenges in neonatal airway management, including anatomical and physiological principles which must be understood to approach the airway. We then follow with a description of current evidence for best practices and training.

Impact of a Care Bundle on Cost Saving for Noninvasive Respiratory Support for Neonates

BACKGROUND

Neonates often receive noninvasive respiratory support via continuous positive airway pressure (CPAP) or high-flow nasal cannula oxygen (HHFNC). The decision to change from one mode to the other, however, is not evidence based, hence not standardized and does not consider cost implications.

PURPOSE

To assess the introduction of a care bundle for the medical and nursing staff in a tertiary medical and surgical neonatal center with regard to any financial savings or adverse outcomes.

METHODS

An education package and written guidelines were used to increase the awareness of the durations for which CPAP and HHFNC Vapotherm (VT) circuits could be used and the costs of the circuits.

RESULTS

This resulted in a cost saving of £17,000 ($22,254) for the year without adverse outcomes.

IMPLICATIONS FOR PRACTICE

Introduction of a care bundle involving an education package and written guidelines to increase the awareness of the durations that circuits could be used and the costs of CPAP and HHFNC circuits among the medical and nursing staff can lead to cost savings when incorporated into clinical practice.

IMPLICATIONS FOR RESEARCH

Strategies, particularly during weaning, which involve changing from one form of noninvasive respiratory support to another, need a greater evidence base. Future research should include awareness of the duration different circuits could be used and the cost implications of changes between modes and hence circuits.

High-flow nasal cannula versus continuous positive airway pressure in primary respiratory support for preterm infants: A systematic review and meta-analysis

Respiratory support is crucial for the survival of preterm infants, and High-flow Nasal Cannula Oxygen Therapy (HFNC) and Continuous Positive Airway Pressure (CPAP) are commonly used for neonatal respiratory support. This meta-analysis aimed to compare the effects of HFNC and CPAP in primary respiratory support for preterm infants, to provide evidence-based support for clinical practice. PubMed, Embase, Cochrane Library, ClinicalTrials.gov, CNKI, VIP, WANFANG and SinoMed were searched for eligible studies. The primary outcomes included the incidence of treatment failure and the application of mechanical ventilation. A total of 27 eligible studies with 3,351 participants were included. There was no significant difference in the incidence of respiratory support failure [RR = 1.17, 95%CI (0.88-1.56)] and the application of mechanical ventilation [RR = 1.00, 95%CI (0.84-1.19)] between HFNC group and CPAP group. HFNC resulted in lower rate of air leaks [RR = 0.65, 95%CI (0.46-0.92)], nasal trauma [RR = 0.36, 95%CI (0.29-0.45)] and abdominal distension [RR = 0.39, 95%CI (0.27-0.58)], and later time of mechanical ventilation initiating [SMD = 0.60, 95%CI (0.21-0.99)], less duration of oxygen therapy [SMD = -0.35, 95%CI (-0.68 to -0.02)] and earlier enteral feeding [SMD = -0.54, 95%CI (-0.95 to -0.13)]. Alternative non-invasive respiratory support after initial treatment failure resulted in no difference in the application of mechanical ventilation between the two groups [RR = 0.99, 95%CI (0.52-1.88)]. HFNC might be more effective and safer in primary respiratory support for preterm infants. Using CPAP as a remedy for the treatment failure of HFNC could not avoid intubation. For premature infants with the gestational age <28 weeks, HFNC as primary respiratory support still needs to be further elucidated. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022313479, identifier: CRD42022313479.

Non-Invasive Ventilation Strategies in Children With Acute Lower Respiratory Infection: A Systematic Review and Bayesian Network Meta-Analysis

Background: Multiple non-invasive ventilation (NIV) modalities have been identified that may improve the prognosis of pediatric patients with acute lower respiratory infection (ALRI). However, the effect of NIV in children with ALRI remains inconclusive. Hence, this study aimed to evaluate the efficacy of various NIV strategies including continuous positive airway pressure (CPAP), high flow nasal cannula (HFNC), bilevel positive airway pressure (BIPAP), and standard oxygen therapy in children with ALRI and the need for supplemental oxygen. Methods: Embase, PubMed, Cochrane Library, and Web of Science databases were searched from inception to July 2021. Randomized controlled trials (RCTs) that compared different NIV modalities for children with ALRI and the need for supplemental oxygen were included. Data were independently extracted by two reviewers. Primary outcomes were intubation and treatment failure rates. Secondary outcome was in-hospital mortality. Pairwise and Bayesian network meta-analyses within the random-effects model were used to synthesize data. The certainty of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation framework. Results: A total of 21 RCTs involving 5,342 children were included. Compared with standard oxygen therapy, CPAP (OR: 0.40, 95% CrI: 0.16-0.90, moderate quality) was associated with a lower risk of intubation. Furthermore, both CPAP (OR: 0.42, 95% CrI: 0.19-0.81, low quality) and HFNC (OR: 0.51, 95% CrI: 0.29-0.81, low quality) reduced treatment failure compared with standard oxygen therapy. There were no significant differences among all interventions for in-hospital mortality. Network meta-regression showed that there were no statistically significant subgroup effects. Conclusion: Among children with ALRI and the need for supplemental oxygen, CPAP reduced the risk of intubation when compared to standard oxygen therapy. Both CPAP and HFNC were associated with a lower risk of treatment failure than standard oxygen therapy. However, evidence is still lacking to show benefits concerning mortality between different interventions. Further large-scale, multicenter studies are needed to confirm our results. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=172156, identifier: CRD42020172156.

High-flow nasal cannula in children with asthma exacerbation: A review of current evidence

Asthma is the commonest obstructive airway disease and the leading cause of morbidity in children. In the pediatric population, acute exacerbations of asthma are a frequent cause of presentations and hospital admissions. An acute asthma exacerbation is potentially life-threatening; it is predominantly treated using conventional oxygen therapy with bronchodilators and systemic corticosteroids. The treatment of those who do not respond to conventional therapy is escalated to noninvasive positive pressure ventilation (NIPPV) before invasive ventilation. Although NIPPV has demonstrated benefits and safety, it still has limitations such as treatment intolerance caused mainly by discomfort and complications. High-flow oxygen therapy administered through a nasal cannula (HFNC) provides respiratory support with adequate airway humidity and has demonstrated safety and benefits in clinical practice. In the present review, we discuss HFNC and variations in HFNC use, focusing on its feasibility and current evidence of using it on children with asthma exacerbations.

Pharyngeal pressure due to high-flow nasal cannula devices in preterm infants

BACKGROUND

In infants, a high-flow nasal cannula (HFNC) generates continuous positive pressure on the upper airway. This study aimed to evaluate the association between pharyngeal pressure and flow rate, and the association between pharyngeal pressure and bodyweight for two types of HFNC devices commonly used in preterm infants: the Optiflow Junior, hereafter "FP" (Fisher & Paykel, Auckland, New Zealand), and the Precision Flow, hereafter "VT" (Vapotherm, Exeter, NH, USA).

METHODS

Pharyngeal pressure measurements were performed in 12 preterm infants who received HFNC support. Flow rates of 1 to 4 L/kg/min were studied.

RESULTS

The median weight at the time of measurement was 1,290 g (range, 953-1,932 g). The FP was used in eight infants and the VT in four. In both of the groups, the flow rate and pharyngeal pressure appeared to be positively correlated except for the premature cannula in the FP group. At a flow rate of ≥2 L/kg/min, there was a positive correlation between the bodyweight and pharyngeal pressure in infants with premature and neonatal cannulas in the FP group. Conversely, at the same flow rate, there was a negative correlation between the bodyweight and pharyngeal pressure in infants with a SOLO cannula in the VT group.

CONCLUSIONS

In preterm infants, the flow rate and pharyngeal pressure were positively correlated in many HFNC cannulas. However, the pharyngeal pressure and bodyweight appeared to be positively and negatively correlated in the FP and VT groups, respectively. Future studies with larger sample sizes should further investigate this issue.

Effect of continuous positive airway pressure versus nasal cannula on late preterm and term infants with transient tachypnea of the newborn

OBJECTIVE

To compare continuous positive airway pressure (CPAP) with nasal cannula (NC) as primary noninvasive respiratory therapy in hypoxic infants for transient tachypnea of the newborn (TTN).

STUDY DESIGN

Retrospective cohort study of infants born at ≥34 weeks of gestation between January 1, 2015 and December 31, 2018.

RESULT

After adjusting for gestational age and birth weight, the maximum fractional inspired oxygen (FiO₂) was significantly lower in the CPAP group with an incidence rate ratio (IRR) of 0.85 (95% CI: 0.76-0.96). Although nonsignificant, the CPAP group needed 32% fewer hours on oxygen with an IRR of 0.68 (95% CI: 0.38-1.22). The duration of respiratory support and the incidence of pneumothorax were similar between both groups.

CONCLUSION

Comparing CPAP with NC as initial noninvasive respiratory therapy for TTN, significantly lower maximum FiO₂ was observed in the infants of CPAP group without increase in the incidence of pneumothorax.

Gas flow in preterm infants treated with bubble CPAP: an observational study

OBJECTIVE

To measure the nasal gas flow in infants treated with bubble continuous positive airway pressure (CPAP) and compare it with commonly used flows during nasal high flow (nHF) treatment.

DESIGN

This is a prospective, single-centre study. Bubble CPAP pressure was measured at the nasal prongs. Set gas flow was reduced until bubbling in the water chamber just ceased. Set gas flow without bubbling then approximated flow entering the infant's nose ('delivered flow').

SETTING

Neonatal intensive care at The Royal Women's Hospital, Melbourne, Australia.

PATIENTS

Clinically stable preterm infants receiving bubble CPAP therapy.

MAIN OUTCOME MEASURE

Delivered flow (L/min) when bubbling stopped at a range of clinically set CPAP pressures (cm H₂O).

RESULTS

Forty-four infants were studied, with a mean (SD) gestational age at birth of 28.4 (2.2) weeks and birth weight of 1154 (419) g. At the time of the study, infants had a median (IQR) age of 4.5 (2-12) days and a mean (SD) weight of 1205 (407) g. Delivered flow ranged from 0.5 to 9.0 L/min, and increased with higher set CPAP pressures (median 3.5 L/min at CPAP 5 cm H₂O vs 6.3 L/min at CPAP 8 cm H₂O) and heavier weights (median 3.5 L/min in infants <1000 g vs 6.5 L/min for infants >1500 g).

CONCLUSIONS

Nasal gas flows during bubble CPAP in preterm infants are similar to flows used during nHF and increase with higher set bubble CPAP pressures and in larger infants. Trial registration number ACTRN12619000197134.

Application of a High-Flow Nasal Cannula for Prevention of Postextubation Atelectasis in Children Undergoing Surgery: A Randomized Controlled Trial

BACKGROUND

General anesthesia-induced atelectasis is common, and persistent postoperative atelectasis is associated with pulmonary complications. We aimed to evaluate the preventive effects of a high-flow nasal cannula (HFNC) on postoperative atelectasis and respiratory complications in infants and small children.

METHODS

In this prospective randomized controlled trial, children (≤2 years) receiving general anesthesia (>2 hours) were randomized into the control and HFNC groups. At the end of the surgery, the first lung ultrasound evaluation was performed in both groups. In the postanesthetic care unit (PACU), the control group received conventional oxygen therapy, while the HFNC group received oxygen via HFNC, with a flow rate of 2 L kg-1 min-1. Before discharge to the ward, a second lung ultrasound examination was performed. The primary outcome was the lung ultrasound score at PACU discharge. The secondary outcomes included the lung ultrasound score at the end of surgery, the incidence of significant atelectasis at PACU discharge, and other postoperative outcomes.

RESULTS

Lung ultrasound score and the incidence of atelectasis at the end of surgery did not differ significantly between the control (n = 38) and HFNC (n = 40) groups. After staying in the PACU, both groups showed a reduced lung ultrasound score and atelectasis incidence. However, the HFNC group had a significantly lower consolidation score than the control group (0; interquartile range [IQR] = 0-1 vs 3; IQR = 2-4; P< .001). Additionally, none of the patients had significant atelectasis in the HFNC group, compared to 6 patients in the control group (0% vs 15.8%; odds ratio [OR] = 0.444; 95% confidence interval for OR, 0.343-0.575; P = .011). Incidence of desaturation (oxygen saturation [Spo2] ≤ 95%), postoperative complications, and the length of hospital stay did not differ between the groups.

CONCLUSIONS

Preventive use of HFNC after surgery improves the lung ultrasound score and reduces postoperative atelectasis compared to conventional oxygen therapy in infants and small children.

Use of heated humidified high flow nasal cannula for obstructive sleep apnea in infants

OBJECTIVE

Heated humidified high flow nasal cannula (HHHFNC) has gained popularity in the treatment of children with respiratory distress and bronchiolitis in the past decade. Its efficacy as a mode of non-invasive respiratory support has been demonstrated in both adults and children. However, reports on its use in the treatment of obstructive sleep apnea (OSA) in infants are limited. We aimed to evaluate the efficacy of HHHFNC therapy as treatment in infants with OSA.

METHODS

A retrospective analysis of OSA infants who had undergone polysomnographic titration between 2015 and 2017 was undertaken. Data about the age, gender, AHI, co-morbid conditions and flow used for each patient were retrieved.

RESULTS

Ten infants were included in this study (median age 34 weeks; IQR 27-38 weeks). The median optimal HHHFNC flow rate was 8.0 L/min (IQR 6.7-8.0 L/min). HHHFNC significantly reduced median obstructive apnea-hypopnea index (OAHI) from 9.1 (IQR 5.1-19.3) to 0.9 (IQR 0-1.6; P = 0.005) events/h; median obstructive apnea index (OAI) from 5.8 (IQR 1.1-13.4) to 0 (IQR 0-0.9; P = 0.021) events/h; median obstructive hypopnea index (OHI) from 4.1 (IQR 0.9-6.8) to 0.1 (0-0.9; P = 0.017) events/h; and median oxygen saturation (SpO2) nadir increased from 88% (IQR 83-94%) to 94% (IQR 93-96%; P = 0.040).

CONCLUSION

HHHFNC significantly reduced respiratory events and improved oxygenation in infants with OSA.

Measurement of airway pressure during high-flow nasal therapy in apnoeic oxygenation: a randomised controlled crossover trial. Anaesthesia 2020;76:27-35. [PMID: 32776518 DOI: 10.1111/anae.15224]

It is recognised that high-flow nasal therapy can prevent desaturation during airway management. Studies in spontaneously breathing patients show an almost linear relationship between flow rate and positive airway pressure in the nasopharynx. Positive airway pressure has been suggested as one of the possible mechanisms explaining how high-flow nasal therapy works. However, data on pressures generated by high-flow nasal therapy in apnoeic adults under general anaesthesia are absent. This randomised controlled crossover trial investigated airway pressures generated by different flow rates during high-flow nasal therapy in anaesthetised and paralysed apnoeic patients, comparing pressures with closed and open mouths. Following induction of anaesthesia and neuromuscular blockade, a continuous jaw thrust was used to enable airway patency. Airway pressure was measured in the right main bronchus, the middle of the trachea and the pharynx, using a fibreoptically-placed catheter connected to a pressure transducer. Each measurement was randomised with respect to closed or open mouth and different flow rates. Twenty patients undergoing elective surgery were included (mean (SD) age 38 (18) years, BMI 25.0 (3.3) kg.m^-2 , nine women, ASA physical status 1 (35%), 2 (55%), 3 (10%). While closed mouths and increasing flow rates demonstrated non-linear increases in pressure, the pressure increase was negligible with an open mouth. Airway pressures remained below 10 cmH₂ O even with closed mouths and flow rates up to 80 l.min^-1 ; they were not influenced by catheter position. This study shows an increase in airway pressures with closed mouths that depends on flow rate. The generated pressure is negligible with an open mouth. These data question positive airway pressure as an important mechanism for maintenance of oxygenation during apnoea.

Nasal high flow in preterm infants: A dose-finding study

OBJECTIVE

To investigate the relationship between applied flows of nasal high flow (NHF) and physiological outcomes and work of breathing (WOB), to identify an optimal delivery flow which results in reduced WOB in preterm infants.

DESIGN

A prospective observational clinical study with randomly applied NHF rates.

PATIENTS AND SETTING

Preterm infants within 72 hours of commencement of NHF respiratory support.

INTERVENTIONS

Infants were initially placed on 8 L/min of NHF and flows of 2, 4, and 6 L/min were then applied in random order.

MEASUREMENTS AND RESULTS

WOB was measured using transcutaneous electromyography and respiratory inductance plethysmography. Physiological variables were also recorded. Measurements taken 10 minutes after each flow change were compared with 8 L/min. Sixteen infants with a median gestational age of 28 (range 24-31) weeks and postnatal age of 14 (2-55) days were included in the study. The median flow rate before the study was 6 (4-8) L/min and a fraction of inspired oxygen (FiO₂ ) was 0.21 (0.21-0.26). Changes in flow resulted in changes in activity in the front diaphragm (P = .027) and intercostals (P = .034). The electrical activity of the front diaphragm at 8 L/min was significantly lower than that at 2 L/min (P = .016). Respiratory rate was lowest at 6 L/min (P = .002) and SpO₂ /FiO₂ was highest at 8 L/min (P < .04).

CONCLUSION

In preterm infants, changes in WOB resulting from randomly applied levels of NHF can be demonstrated by measuring the electrical activity of the diaphragm and intercostal muscles with transcutaneous electromyography. In combination with physiological measurements, the similarities in electrical activity between 4, 6, and 8 L/min suggest that these three flows may be equally as effective.

Mechanisms of nasal high flow therapy in newborns

In newborns, it is unclear how nasal high flow (NHF) generates positive airway pressure. In addition, the reported benefits of NHF such as reduction in work of breathing may be independent of airway pressure. The authors hypothesized that during NHF the area of leak and the flow determine airway pressure and that NHF can reduce the required minute ventilation to maintain gas exchange. In response to NHF, pressure was measured in the upper airways of 9 newborns and ventilation was measured in another group of 17 newborns. In a bench model, airway pressures were measured during NHF with different prong sizes, nare sizes, and flows. The airway pressures during 8 L/min NHF were greater when a larger cannula versus a smaller cannula was used (P < 0.05). NHF reduced minute ventilation in 16 of 17 neonates, with a mean decrease of 24% from a baseline of 0.66 L/min (SD 0.21) (P < 0.001), and was unrelated to changes in airway pressure; arterial oxygen saturation by pulse oximetry (SpO2) and tissue CO₂ were unchanged. In the bench model, the airway pressure remained <2 cmH₂O when <50% of the “nare” was occluded by the prongs. As the leak area decreased, because of a smaller nare or a larger cannula, the airway pressure increased exponentially and was dependent on flow. In newborns NHF using room air substantially reduced minute ventilation without affecting gas exchange irrespective of a decrease or an increase of respiratory rate. NHF generates low positive airway pressure that exponentially increases with flow and occlusion of the nares.

NEW & NOTEWORTHY In healthy newborns, nasal high flow (NHF) with room air reduced minute ventilation by one-fourth without affecting gas exchange but, in contrast to adults, produced variable response in respiratory rate during sleep. During NHF, pressure in the upper airways did not exceed 2 cmH₂O at 8 L/min (3.4 L·min⁻¹·kg⁻¹) and was unaffected by opening of the mouth. NHF can generate higher pressure with larger prongs that decrease the leak around the cannula or by increasing the flow rate.

Physiological effects of high-flow nasal cannula therapy in preterm infants

OBJECTIVE

High-flow nasal cannula (HFNC) therapy is increasingly used in preterm infants despite a paucity of physiological studies. We aimed to investigate the effects of HFNC on respiratory physiology.

STUDY DESIGN

A prospective randomised crossover study was performed enrolling clinically stable preterm infants receiving either HFNC or nasal continuous positive airway pressure (nCPAP). Infants in three current weight groups were studied: <1000 g, 1000-1500 g and >1500 g. Infants were randomised to either first receive HFNC flows 8-2 L/min and then nCPAP 6 cm H₂O or nCPAP first and then HFNC flows 8-2 L/min. Nasopharyngeal end-expiratory airway pressure (pEEP), tidal volume, dead space washout by nasopharyngeal end-expiratory CO₂ (pEECO₂), oxygen saturation and vital signs were measured.

RESULTS

A total of 44 preterm infants, birth weights 500-1900 g, were studied. Increasing flows from 2 to 8 L/min significantly increased pEEP (mean 2.3-6.1 cm H₂O) and reduced pEECO₂ (mean 2.3%-0.9%). Tidal volume and transcutaneous CO₂ were unchanged. Significant differences were seen between pEEP generated in open and closed mouth states across all HFNC flows (difference 0.6-2.3 cm H₂O). Infants weighing <1000 g received higher pEEP at the same HFNC flow than infants weighing >1000 g. Variability of pEEP generated at HFNC flows of 6-8 L/min was greater than nCPAP (2.4-13.5 vs 3.5-9.9 cm H₂O).

CONCLUSIONS

HFNC therapy produces clinically significant pEEP with large variability at higher flow rates. Highest pressures were observed in infants weighing <1000 g. Flow, weight and mouth position are all important determinants of pressures generated. Reductions in pEECO₂ support HFNC's role in dead space washout.

Mechanistic Understanding of High Flow Nasal Cannula Therapy and Pressure Support with an In Vitro Infant Model

Despite the increased use of high flow nasal cannula therapy, little has been done to predict airway pressures for a full breath cycle. A 3-month-old infant in vitro model was developed, which included the entire upper airway and the first three bifurcations of the lungs. A breathing simulator was used to create a realistic breath pattern, and high flow was provided using a Vapotherm unit. Four cannulas of varying sizes were used to assess the effects of the inner diameter and nasal occlusion of the cannulas on airway pressures. At 8 L min^-1, end expiratory pressures of 0.821-1.306 cm H₂O and 0.828-1.133 cm H₂O were produced in the nasopharynx and trachea, respectively. Correlations were developed to predict full breath cycle airway pressures, based on the gas flow rate delivered, cannula dimensions, as well as the breathing flow rate, for the nasopharynx and trachea. Pearson correlation coefficients for the nasopharynx and trachea correlations were 0.991 and 0.992, respectively. The developed correlations could be used to determine the flow rate necessary for a cannula to produce pressures similar to CPAP settings. The proposed correlations accurately predict the regional airway pressure up to and including 7 cm H₂O of support for the entire breath cycle.

Is Nasal High Flow Inferior to Continuous Positive Airway Pressure for Neonates?

Nasal high-flow therapy (nHF) is increasingly used for neonates, with perceived benefits including reduced rates of nasal trauma and parent and nursing staff preference. Current evidence suggests that although nHF is a reasonable alternative for postextubation support of preterm infants, continuous positive airway pressure is a superior modality for primary support of respiratory distress syndrome. Minimal evidence exists for use of nHF in extremely preterm infants less than 28 weeks' gestation. Depending on clinician preference, units may still choose nHF in some settings, although careful choice of appropriate patients, and availability of rescue continuous positive airway pressure, is essential.

Effect of randomization of nasal high flow rate in preterm infants

OBJECTIVE

To assess the effect of nasal high flow (NHF) cannula on end-expiratory level (EEL), continuous distending pressure (CDP) and regional ventilation distribution in preterm infants.

DESIGN

A prospective observational clinical study with randomly applied NHF rates.

PATIENTS AND SETTING

Preterm infants requiring continuous positive airway pressure (CPAP) respiratory support in a Neonatal Intensive Care Unit.

INTERVENTIONS

Infants were measured on randomly applied flow rates at 2, 4, and 6 L/min of NHF and compared with bubble CPAP.

MEASUREMENTS AND RESULTS

Regional ventilation distribution and EEL were measured using electrical impedance tomography (EIT) and respiratory inductance plethysmography (RIP) in 24 preterm infants (31.19 ± 1.17 weeks corrected age). Changes in CDP were measured from the esophagus via the nasogastric tube. Physiological variables were also recorded. There were no differences in ventilation distribution, EEL or CDP between CPAP and NHF (P > .05). However, the physiological variables of FiO₂ (P = .01) and SpO₂ /FiO₂ (P < .01) were improved on CPAP compared with NHF.

CONCLUSION

NHF applied in random order with flow rates between 2 to 6 L/min was equally as good as CPAP in maintaining EEL and ventilation distribution in stable preterm infants. Overall oxygenation was better on CPAP compared to NHF.

Nasal high flow therapy for neonates: Current evidence and future directions

Nasal high flow (nHF) therapy is a commonly used method of providing non-invasive respiratory support for neonates. It has several potential mechanisms of action: continuous distending pressure, nasopharyngeal dead space washout, provision of heated and humidified gases and reduction of work of breathing. nHF is used in a number of clinical scenarios for preterm and term infants, including primary respiratory and post-extubation support. In recent years, large trials have generated evidence pertinent to these indications. Novel applications for nHF in neonates warrant further research: during endotracheal intubation, for initial delivery room stabilisation of preterm infants and in conjunction with minimally invasive surfactant therapy.

Positive Airway Pressure Versus High-Flow Nasal Cannula for Prevention of Extubation Failure in Infants After Congenital Heart Surgery

OBJECTIVES

Compare the impact of initial extubation to positive airway pressure versus high-flow nasal cannula on postoperative outcomes in neonates and infants after congenital heart surgery.

DESIGN

Retrospective cohort study with propensity-matched analysis.

SETTING

Cardiac ICU within a tertiary care children's hospital.

PATIENTS

Patients less than 6 months old initially extubated to either high-flow nasal cannula or positive airway pressure after cardiac surgery with cardiopulmonary bypass were included (July 2012 to December 2015).

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Of 258 encounters, propensity matching identified 49 pairings of patients extubated to high-flow nasal cannula versus positive airway pressure. Extubation failure was 12% for all screened encounters. After matching, there was no difference in extubation failure rate between groups (positive airway pressure 16% vs high-flow nasal cannula 10%; p = 0.549). However, compared with high-flow nasal cannula, patients initially extubated to positive airway pressure experienced greater resource utilization: longer time to low-flow nasal cannula (83 vs 28 hr; p = 0.006); longer time to room air (159 vs 110 hr; p = 0.013); and longer postsurgical hospital length of stay (22 vs 14 d; p = 0.015).

CONCLUSIONS

In this pediatric cohort, primary extubation to positive airway pressure was not superior to high-flow nasal cannula with respect to prevention of extubation failure after congenital heart surgery. Compared with high-flow nasal cannula, use of positive airway pressure was associated with increased hospital resource utilization. Prospective initiatives aimed at establishing best clinical practice for postoperative noninvasive respiratory support are needed.

Diaphragm electromyography results at different high flow nasal cannula flow rates

Heated, humidified, high-flow nasal cannula (HHHFNC) is increasingly being used, but there is a paucity of evidence as to the optimum flow rates in prematurely born infants. We have determined the impact of three flow rates on the work of breathing (WOB) assessed by transcutaneous diaphragm electromyography (EMG) amplitude in infants with respiratory distress or bronchopulmonary dysplasia (BPD). Flow rates of 4, 6 and 8 L/min were delivered in random order. The mean amplitude of the EMG trace and mean area under the EMG curve (AEMGC) were calculated and the occurrence of bradycardias and desaturations recorded. Eighteen infants were studied with a median gestational age of 27.8 (range 23.9-33.5) weeks and postnatal age of 54 (range 3-122) days. The median flow rate prior to the study was 5 (range 3-8) L/min and the fraction of inspired oxygen (FiO₂) was 0.29 (range 0.21-0.50). There were no significant differences between the mean amplitude of the diaphragm EMG and the AEGMC and the number of bradycardias or desaturations between the three flow rates.Conclusions: In infants with respiratory distress or BPD, there was no advantage of using high (8 L/min) compared with lower flow rates (4 or 6 L/min) during support by HHHFNC. What is known: • Humidified high flow nasal cannulae (HHHFNC) is increasingly being used as a non-invasive form of respiratory support for prematurely born infants. • There is a paucity of evidence regarding the optimum flow rate with 1 to 8 L/min being used. What is new: • We have assessed the work of breathing using the amplitude of the electromyogram of the diaphragm at three HHHFNC flow rates in infants with respiratory distress or BPD. • No significant differences were found in the EMG amplitude results or the numbers of bradycardias or desaturations at 4, 6 and 8 L/min.

Pilot Clinical Trial of High-Flow Oxygen Therapy in Children with Asthma in the Emergency Service

OBJECTIVES

To assess the efficacy of high-flow nasal cannula (HFNC) oxygen therapy and safety in children with asthma and moderate respiratory failure in the emergency department (ED).

STUDY DESIGN

This was a prospective randomized pilot trial of children (aged 1-14 years) presenting to a tertiary academic pediatric ED with moderate-to-severe asthma exacerbations between September 2012 and December 2015. Patients with a pulmonary score (PS) ≥6 or oxygen saturation <94% with a face mask despite initial treatment (salbutamol/ipratropium bromide and corticosteroids) were randomized to HFNC or to conventional oxygen therapy. Pharmacologic treatment was at the discretion of attending physicians. The primary outcome was a decrease in PS ≥2 in the first 2 hours. Secondary outcomes included disposition, length of stay, and need for additional therapies.

RESULTS

We randomly allocated 62 children to receive either HFNC (n = 30) or standard oxygen therapy (n = 32). Baseline patient characteristics were similar in the 2 groups. At 2 hours after the start of therapy, PS had decreased by ≥2 points in 16 patients in the HFNC group (53%) compared with 9 controls (28%) (P = .01). Between-group differences in disposition, length of stay, and need for additional therapies were not significant. No side effects were reported.

CONCLUSION

HFNC appears to be superior to conventional oxygen therapy for reducing respiratory distress within the first 2 hours of treatment in children with moderate-to-severe asthma exacerbation refractory to first-line treatment. Further studies are needed to demonstrate its overall efficacy in the management of asthma and respiratory failure in the ED.

TRIAL REGISTRATION

EudraCT: 2012-001771-36.

Children's Oxygen Administration Strategies Trial (COAST): A randomised controlled trial of high flow versus oxygen versus control in African children with severe pneumonia

Background: In Africa, the clinical syndrome of pneumonia remains the leading cause of morbidity and mortality in children in the post-neonatal period. This represents a significant burden on in-patient services. The targeted use of oxygen and simple, non-invasive methods of respiratory support may be a highly cost-effective means of improving outcome, but the optimal oxygen saturation threshold that results in benefit and the best strategy for delivery are yet to be tested in adequately powered randomised controlled trials. There is, however, an accumulating literature about the harms of oxygen therapy across a range of acute and emergency situations that have stimulated a number of trials investigating permissive hypoxia. Methods: In 4200 African children, aged 2 months to 12 years, presenting to 5 hospitals in East Africa with respiratory distress and hypoxia (oxygen saturation < 92%), the COAST trial will simultaneously evaluate two related interventions (targeted use of oxygen with respect to the optimal oxygen saturation threshold for treatment and mode of delivery) to reduce shorter-term mortality at 48-hours (primary endpoint), and longer-term morbidity and mortality to 28 days in a fractional factorial design, that compares: Liberal oxygenation (recommended care) compared with a strategy that permits hypoxia to SpO 2 > or = 80% (permissive hypoxia); andHigh flow using AIrVO 2 TM compared with low flow delivery (routine care). Discussion: The overarching objective is to address the key research gaps in the therapeutic use of oxygen in resource-limited setting in order to provide a better evidence base for future management guidelines. The trial has been designed to address the poor outcomes of children in sub-Saharan Africa, which are associated with high rates of in-hospital mortality, 9-10% (for those with oxygen saturations of 80-92%) and 26-30% case fatality for those with oxygen saturations <80%. Clinical trial registration: ISRCTN15622505 Trial status: Recruiting.

High-Flow Nasal Cannula versus Conventional Oxygen Therapy in Children with Respiratory Distress

Purpose:

The aim of this study is to determine the clinical efficacy of high-flow nasal cannula (HFNC) therapy compared with conventional oxygen therapy in children presented with respiratory distress.

Study Design:

This was a randomized controlled study.

Materials and Methods:

Infants and children aged between 1 month to 5 years who were admitted to our tertiary referral center for respiratory distress (July 1, 2014 to March 31, 2015) and met the inclusion criteria were recruited.

Interventions:

Infants and children hospitalized with respiratory distress were randomized into two groups of interventions. All clinical data, for example, respiratory score, pulse rate, and respiratory rate were recorded. The results were subsequently analyzed.

Results:

A total of 98 respiratory distress children were enrolled during the study period. Only 4 children (8.2%) failed in HFNC therapy, compared with 10 children (20.4%) in conventional oxygen therapy group (P = 0.09). After adjusted for body weight, underlying diseases, and respiratory distress score, there was an 85% reduction in the odds of treatment failure in HFNC therapy group (adjusted odds ratio 0.15, 95% confidence interval 0.03–0.66, P = 0.01). Most children in HFNC therapy group had significant improvement in clinical respiratory score, heart rate, and respiratory rate at 240, 360, and 120 min compared with conventional oxygen therapy (P = 0.03, 0.04, and 0.03).

Conclusion:

HFNC therapy revealed a potential clinical advantage in management children hospitalized with respiratory distress compared with conventional respiratory therapy. The early use of HFNC in children with moderate-to-severe respiratory distress may prevent endotracheal tube intubation.

Trial Register:

TCTR 20170222007.

National high-flow nasal cannula and bronchiolitis survey highlights need for further research and evidence-based guidelines

AIM

High-flow nasal cannula (HFNC) therapy provides noninvasive respiratory support for infant bronchiolitis and its use has increased following good clinical experiences. This national study describes HFNC use in Finland during a severe respiratory syncytial virus (RSV) epidemic.

METHODS

A questionnaire on using HFNC for infant bronchiolitis during the 2015-2016 RSV epidemic was sent to the head physicians of 18 Finnish children's hospitals providing inpatient care for infants: 17 hospitals answered, covering 77.5% of the infants born in Finland in 2015.

RESULTS

Most (85%) HFNC was given on paediatric wards. The mean incidence for bronchiolitis treated with HFNC in infants under the age of one in 15 of 17 hospitals was 3.8 per 1000 per year (range: 1.4-8.1): one hospital did not supply the relevant data and one supplied a figure of 34.1 due to a different treatment policy. Instructions on how to start and wean HFNC therapy were present in 71% and 61% of the hospitals, respectively, weighted to the population. Providing weaning instructions was associated with shorter weaning times.

CONCLUSION

High-flow nasal cannula was actively used for infants with bronchiolitis, with no substantial overuse. Randomised controlled studies are needed before any evidence-based guidelines can be constructed for using HFNC in infant bronchiolitis.

Efficacy and safety of nasal high-flow oxygen in COPD patients

Background

Nasal high-flow oxygen therapy (HFOT) is a novel treatment option for patients suffering from acute or chronic respiratory failure. Aim of our study was to compare safety and efficacy of HFOT with those of conventional oxygen treatment (COT) in normo- and hypercapnic COPD patients.

Methods

A single cohort of 77 clinically stable hypoxemic patients with an indication for long-term oxygen treatment (LTOT) with or without hypercapnia successively received COT and HFOT for 60 min each, including oxygen adaption and separated by a 30 min washout phase.

Results

HFOT was well-tolerated in all patients. A significant decrease in PaCO₂ was observed during oxygen adaption of HFOT, and increased PaO₂ coincided with significantly increased SpO₂ and decreased AaDO₂ during both treatment phases. Even at a flow rate of 15 L/min, oxygen requirement delivered as air mixture by HFOT tended to be lower than that of COT (2.2 L/min). Not only was no increase in static or dynamic lung volumes observed during HFOT, but even was a significant reduction of residual lung volume measured in 36 patients (28%).

Conclusions

Thus, short-term use of HFOT is safe in both normocapnic and hypercapnic COPD patients. Lower oxygen levels were effective in correcting hypoxemic respiratory failure and reducing hypercapnia, leading to a reduced amount of oxygen consumption. Long-term studies are needed to assess safety, tolerability, and clinical efficacy of HFOT.

Trial registration

ClinicalTrials.gov NCT01686893 13.09.2012 retrospectively registered (STIT-1) and NCT01693146 14.09.2012 retrospectively registered (STIT-2). Studies were approved by the local ethics committee (Ethikkommission der Medizinischen Universität Innsbruck, Studienkennzahl UN3547, Sitzungsnummer 274/4.19).

Children's Oxygen Administration Strategies Trial (COAST): A randomised controlled trial of high flow versus oxygen versus control in African children with severe pneumonia

Background: In Africa, the clinical syndrome of pneumonia remains the leading cause of morbidity and mortality in children in the post-neonatal period. This represents a significant burden on in-patient services. The targeted use of oxygen and simple, non-invasive methods of respiratory support may be a highly cost-effective means of improving outcome, but the optimal oxygen saturation threshold that results in benefit and the best strategy for delivery are yet to be tested in adequately powered randomised controlled trials. There is, however, an accumulating literature about the harms of oxygen therapy across a range of acute and emergency situations that have stimulated a number of trials investigating permissive hypoxia. Methods: In 4200 African children, aged 2 months to 12 years, presenting to 5 hospitals in East Africa with respiratory distress and hypoxia (oxygen saturation < 92%), the COAST trial will simultaneously evaluate two related interventions (targeted use of oxygen with respect to the optimal oxygen saturation threshold for treatment and mode of delivery) to reduce shorter-term mortality at 48-hours (primary endpoint), and longer-term morbidity and mortality to 28 days in a fractional factorial design, that compares: Liberal oxygenation (recommended care) compared with a strategy that permits hypoxia to SpO 2 > or = 80% (permissive hypoxia); andHigh flow using AIrVO 2TM compared with low flow delivery (routine care). Discussion: The overarching objective is to address the key research gaps in the therapeutic use of oxygen in resource-limited setting in order to provide a better evidence base for future management guidelines. The trial has been designed to address the poor outcomes of children in sub-Saharan Africa, which are associated with high rates of in-hospital mortality, 9-10% (for those with oxygen saturations of 80-92%) and 26-30% case fatality for those with oxygen saturations <80%. Clinical trial registration: ISRCTN15622505 Trial status: Recruiting.

Nasal high flow treatment in preterm infants

Nasal High Flow (HF) is a mode of ‘non-invasive’ respiratory support for preterm infants, with several potential modes of action, including generation of distending airway pressure, washout of the nasopharyngeal dead space, reduction of work of breathing, and heating and humidification of inspired gas. HF has several potential advantages over continuous positive airway pressure (CPAP), the most commonly applied form of non-invasive support, such as reduced nasal trauma, ease of use, and infant comfort, which has led to its rapid adoption into neonatal care. In recent years, HF has become a well-established and commonly applied treatment in neonatal care.

Recent trials comparing HF and CPAP as primary support have had differing results. Meta-analyses suggest that primary HF results in an increased risk of treatment failure, but that ‘rescue’ CPAP use in those infants with HF failure results in no greater risk of mechanical ventilation. Even in studies with higher rates of HF failure, the majority of infants were successfully treated with HF, and rates of important neonatal morbidities did not differ between treatment groups. Importantly, these studies have included only infants born at ≥28 weeks’ gestational age (GA). The decision whether to apply primary HF will depend on the value placed on its advantages over CPAP by clinicians, the approach to surfactant treatment, and the severity of respiratory disease in the relevant population of preterm infants.

Post-extubation HF use results in similar rates of treatment failure, mechanical ventilation, and adverse events compared to CPAP. Post-extubation HF appears most suited to infants ≥28 weeks; there are few published data for infants below this gestation, and available evidence suggests that these infants are at high risk of HF failure, although rates of intubation and other morbidities are similar to those seen with CPAP. There is no evidence that using HF to ‘wean’ off CPAP allows for respiratory support to be ceased more quickly, but given its advantages it would appear to be a suitable alternative in infants who require ongoing non-invasive support. Safety data from randomised trials are reassuring, although more evidence in extremely preterm infants (<28 weeks’ GA) is required.

The Role of Heated Humidified High-flow Nasal Cannula as Noninvasive Respiratory Support in Neonates

Recently, heated humidified high-flow nasal cannula (HHHFNC) has been introduced and applied as a noninvasive respiratory support in neonates. Although HHHFNC is widely used in neonates presenting with respiratory distress, the efficiency and safety when compared with nasal continuous positive airway pressure or noninvasive positive pressure ventilation are still controversial. This review aims to evaluate the performance and applications of HHHFNC in neonates.

Sudden versus gradual pressure wean from Nasal CPAP in preterm infants: a randomized controlled trial

OBJECTIVE

In preterm infants, nasal continuous positive airway pressure (NCPAP) is widely used for treatment of respiratory distress syndrome. However, the strategies for successfully weaning infants off NCPAP are still not well defined and there remains considerable variation between the methods. The objective of this study is to determine whether gradual weaning of NCPAP pressure is more successful than sudden weaning off NCPAP to room air.

STUDY DESIGN

A randomized controlled trial was conducted in a level 3 neonatal intensive care unit on 70 preterm neonates who were born between 26 and 32 weeks gestation and required NCPAP for at least 48 h. When infants were stable on NCPAP at 0.21 FiO₂ and 5 cm H₂O positive end expiratory pressure, neonates were randomized to the gradual wean group (reduction in pressure by 1 cm every 8 h until 3 cm H₂0 was reached) or to sudden wean group (one time NCPAP removal to room air). The primary outcome was a success at the first trial to wean to room air. Secondary outcomes were a number of trials, and weight and postmenstrual age (PMA) at the time of successful wean. Total number of days on NCPAP and length of stay (LOS) in the hospital were also compared between the groups.

RESULTS

Of the 70 infants included in the study, 35 were randomized to sudden group and 33 infants to gradual group (2 excluded for protocol deviation). In sudden and gradual groups, 14 and 22 infants, respectively, were weaned successfully in the first attempt (P=0.03). The infants were successfully weaned at 32.7±1.7 weeks versus 33.1±2.4 weeks (P=0.39) PMA and at a weight of 1651±290 g versus 1589±398 g (P=0.46) in the sudden and gradual groups, respectively. The total number of days on NCPAP was 27±19 days versus 32±24 days (P=0.38) and LOS was 63±25 days versus 63±22 days (P=0.99) in the sudden and gradual groups, respectively.

CONCLUSIONS

Gradual weaning method was more successful as compared to sudden weaning method in the initial trial off NCPAP. There was no difference in the PMA, weight at the time of successful wean, total days on NCPAP and LOS between the two groups.

High-flow nasal cannula therapy beyond the perinatal period

PURPOSE OF REVIEW

High-flow nasal cannula (HFNC) is emerging as a means of oxygen delivery and respiratory support for a range of conditions outside the perinatal period. We aim to review the mechanisms of action and advantages of HFNC and to summarize current findings regarding clinical benefit in specific pediatric disease processes and in patients with significant respiratory distress.

RECENT FINDINGS

Currently published studies outside the neonatal population demonstrate both safety and efficacy of this mode of respiratory support. Retrospective and prospective observational trials have shown improvements in oxygenation and respiratory distress, as well as reductions in the need for intubation in select patient populations. Randomized controlled trials are ongoing.

SUMMARY

HFNC is emerging as a means of oxygen delivery and respiratory support across a wide range of pediatric conditions. Available data suggest that it is well tolerated by children and can have a favorable effect on clinical outcomes. Future research will better define optimal patient populations and best practices for use.

High flow nasal cannula use outside of the ICU; factors associated with failure

OBJECTIVES

High flow nasal cannula (HFNC) use is increasing in pediatrics. Few studies exist examining the safety of HFNC use outside the intensive care unit (ICU). This study aimed to characterize patient qualities associated with failure of HFNC use outside the ICU.

STUDY DESIGN

A retrospective chart review of patients placed on HFNC outside the ICU from September 2011 to July 2013 was completed. Failure was defined as intubation or cardiopulmonary arrest. Two-sample tests and binary logistic regression determined significant factors associated with failed HFNC administration, both unadjusted and adjusted for hospital.

RESULTS

Two hundred thirty-one patients met inclusion criteria, with 192 receiving treatment for a primary respiratory diagnosis (83%). Fourteen (6%) progressed to HFNC failure; 12 transferred to the ICU and were intubated, two with congenital heart disease suffered cardiopulmonary arrest on the floor. Two-sample tests revealed failure patients were more likely to have a cardiac history (P = 0.026), history of intubation (P = 0.040), and require higher fraction of inspired oxygen (FiO₂ ) (median 100%; 25th-75th 60-100%; P = <0.001). Hospital adjusted logistic regression further demonstrated failure patients were more likely to be treated with higher FiO₂ (OR: 38.3; 95% CI: 4.0-366.3; P = 0.002), and less likely to have a diagnosis of bronchiolitis (OR: 0.3; 95% CI: 0.1-0.9; P = 0.048).

CONCLUSIONS

High FiO₂ requirements, history of intubation, and cardiac co-morbidity are associative predictors of HFNC failure. Bronchiolitis patients may be treated with HFNC outside of the ICU with lower odds of failure. Pediatr Pulmonol. 2017;52:806-812. © 2017 Wiley Periodicals, Inc.

High-flow nasal cannula therapies for respiratory management in pediatric patients

High-flow nasal cannula (HFNC) oxygen therapy is a non-invasive form of respiratory support that is rapidly being taken up in pediatric intensive care units (PICU). For infants with bronchiolitis, who are the largest non-elective source of admissions to a PICU, there is some evidence that using HFNC therapy reduces the need for intubation and mechanical ventilation. The aim of this review article is to explore, describe, critique and add to the evidence surrounding the use of HFNC therapy in the pediatric population for the management of respiratory distress.

Thoracoabdominal Asynchrony Is Not Associated with Oxyhemoglobin Saturation in Recovering Premature Infants

BACKGROUND

Recovering premature infants are at risk for hypoxemia and lack of synchrony between their rib cage and abdomen due to airflow obstruction and poor respiratory compliance. Thoracoabdominal asynchrony (TAA) is a useful marker of resistive and elastic lung properties. Whether TAA predicts oxygenation is unknown.

OBJECTIVES

We investigated oxyhemoglobin saturation (SpO2%) and TAA (phase angle, φ) in preterm infants with/without high-humidity nasal cannula (HHNC).

METHODS

A cross-sectional observational study was conducted in 92 infants at 32 weeks' postmenstrual age. We measured SpO2% with pulse oximetry and TAA with φ via respiratory inductance plethysmography in infants (mean gestational age: 26.4 + 1.3 weeks) who required room air (n = 18) or HHNC with/without supplemental oxygen (1-5 liters per minute, FiO2 0.21-0.33, n = 74). We calculated median SpO2% from 24.7 + 10.0 min of quiet sleep and median φ from up to 60 breaths.

RESULTS

Infants breathing room air alone had marked TAA (φ = 83.6 + 32.9°, range: 10.9-148.5) as did those receiving varying degrees of ventilatory and oxygen support via HHNC (range of group means, φ = 47.0-90.0°). Infants breathing room air had statically greater median SpO2% than those receiving support (96.3 + 0.6% vs. 91.3 + 0.6%; ANOVA p = 0.001). SpO2% was not associated with TAA in either group (r2 = 0.09).

CONCLUSION

Recovering premature infants exhibited TAA regardless of need for ventilatory support and supplemental oxygen. TAA was not associated with SpO2% in either group. Maintenance of SpO2% does not require correction of TAA.

Evidence Support and Guidelines for Using Heated, Humidified, High-Flow Nasal Cannulae in Neonatology: Oxford Nasal High-Flow Therapy Meeting, 2015

Nasal high-flow therapy (nHFT) has become a popular form of noninvasive respiratory support in neonatal intensive care units. A meeting held in Oxford, UK, in June 2015 examined the evidence base and proposed a consensus statement. In summary, nHFT is effective for support of preterm infants following extubation. There is growing evidence evaluating its use in the primary treatment of respiratory distress. Further study is needed to assess which clinical conditions are most amenable to nHFT support, the most effective flow rates, and escalation and weaning strategies. Its suitability as first-line treatment needs to be further evaluated.

High Flow Nasal Cannulae versus Nasal Continuous Positive Airway Pressure in Neonates with Respiratory Distress Syndrome Managed with INSURE Method: A Randomized Clinical Trial

BACKGROUND

In recent years, various noninvasive respiratory support (NRS) of ventilation has been provided more in neonates. The aim of this study was to compare the effect of HFNC with NCPAP in post-extubation of preterm infants with RDS after INSURE method (intubation, surfactant, extubation).

METHODS

A total of 54 preterm infants with RDS (respiratory distress syndrome) were enrolled in this study. Using a randomized sequence, they were assigned into two groups after INSURE method. The first group received HFNC while the second group received NCPAP for respiratory support after extubation. A comparison was made between these two groups by the rate of reintubation, air leak syndrome, duration of oxygen therapy, hospitalization, the rate of bronchopulmonary dysplasia (BPD), intraventricular hemorrhage (IVH), retinopathy of prematurity (ROP), and mortality. Data were analyzed by using the SPSS version 18 software. The statistical analyses included Student's t-test for continuous data and compared proportions using Chi-squared test and Fisher's exact test for categorical data.

RESULT

The rate of reintubation was higher in the HFNC compared with the NCPAP group. The rate of either IVH or ROP had no significant differences between the two groups. In addition, duration of oxygen requirement and hospitalization were not statistically different. There was no case of BPD or mortality among these patients.

CONCLUSION

This study showed that preterm infants with RDS could manage post-extubation after INSURE method with either NCPAP or HFNC. However, in this single-center study, the rate of reintubation was higher in the HFNC group while further multicenter study might be assigned. Trial Registration Number: IRCT201201228800N1.

Nasal High-Flow Therapy for Primary Respiratory Support in Preterm Infants

BACKGROUND

Treatment with nasal high-flow therapy has efficacy similar to that of nasal continuous positive airway pressure (CPAP) when used as postextubation support in neonates. The efficacy of high-flow therapy as the primary means of respiratory support for preterm infants with respiratory distress has not been proved.

METHODS

In this international, multicenter, randomized, noninferiority trial, we assigned 564 preterm infants (gestational age, ≥28 weeks 0 days) with early respiratory distress who had not received surfactant replacement to treatment with either nasal high-flow therapy or nasal CPAP. The primary outcome was treatment failure within 72 hours after randomization. Noninferiority was determined by calculating the absolute difference in the risk of the primary outcome; the chosen margin of noninferiority was 10 percentage points. Infants in whom high-flow therapy failed could receive rescue CPAP; infants in whom CPAP failed were intubated and mechanically ventilated.

RESULTS

Trial recruitment stopped early at the recommendation of the independent data and safety monitoring committee because of a significant difference in the primary outcome between treatment groups. Treatment failure occurred in 71 of 278 infants (25.5%) in the high-flow group and in 38 of 286 infants (13.3%) in the CPAP group (risk difference, 12.3 percentage points; 95% confidence interval [CI], 5.8 to 18.7; P<0.001). The rate of intubation within 72 hours did not differ significantly between the high-flow and CPAP groups (15.5% and 11.5%, respectively; risk difference, 3.9 percentage points; 95% CI, -1.7 to 9.6; P=0.17), nor did the rate of adverse events.

CONCLUSIONS

When used as primary support for preterm infants with respiratory distress, high-flow therapy resulted in a significantly higher rate of treatment failure than did CPAP. (Funded by the National Health and Medical Research Council and others; Australian New Zealand Clinical Trials Registry number, ACTRN12613000303741 .).