High-flow nasal cannula therapy for respiratory support in children

Noninvasive Respiratory Support for Pediatric Critical Asthma: A Multicenter Cohort Study

BACKGROUND

Noninvasive respiratory support (NRS) for pediatric critical asthma includes CPAP; bi-level positive airway pressure (BPAP); and heated, humidified, high-flow nasal cannula (HFNC). We used the Virtual Pediatric System database to estimate NRS by prescribing rates for pediatric critical asthma and characterize patient clinical features and in-patient outcomes by the initial NRS device applied.

METHODS

We performed a retrospective cohort study from 125 participating pediatric ICUs among children 2-17 years of age hospitalized for critical asthma and prescribed NRS from 2017 through 2021. The primary outcomes were NRS modality prescribing rates and trends. Secondary outcomes were descriptive and included demographics, comorbidities, severity of illness indices, and NRS failure rates (defined as escalation from the initial NRS modality to invasive ventilation, HFNC to BPAP or CPAP, or CPAP to BPAP).

RESULTS

Of the 10,083 encounters studied, the initial NRS modalities prescribed varied widely by hospital center (HFNC: 69.7 ± 29.6%; BPAP: 27.2 ± 7.1%; CPAP: 3.1 ± 5.9%). The mean rates of HFNC use increased from 59.7% in 2017 to 71.9% in 2021 (+2.5%/y). In contrast, BPAP (-1.6%/y) and CPAP (-0.8%/y) utilization declined throughout the study period. Older children who were obese and with a higher Pediatric Risk of Mortality III-Probability of Mortality score were more frequently prescribed BPAP and CPAP compared with HFNC. Those children on HFNC experienced higher noninvasive respiratory support failure rates versus BPAP (7.3% vs 2.4%; P < .001) but a lower subsequent invasive ventilation rate versus BPAP (0.8% vs 2.4%; P < .001).

CONCLUSIONS

In this multi-center cohort study, we observed that children with critical asthma are increasingly exposed to HFNC compared with BPAP and CPAP. Rates of HFNC failure were greater than those of BPAP failure, but a majority were transitioned to BPAP without subsequent invasive ventilation. The next steps include prospective trials, including practical end points such as patient comfort and optimal delivery of nebulized treatments to distinguish device superiority and suitable NRS utilization.

Post-acute day and night non-invasive respiratory intervention use and outcome: A brief report

OBJECTIVE

This study aimed to describe daytime and nighttime use and outcome of non-invasive respiratory intervention (NIRI) for infants born prematurely and for children with medical complexity (CMC) during a post-acute care hospital (PACH) admission.

METHODS

Thirty-eight initial PACH admissions (October 2018 through September 2020) for premature infants (< 1 year; n = 19) and CMC (> 1 year; n = 19) requiring NIRI during the day and/or at night were retrospectively examined. Measures included: 1) daytime and nighttime NIRI use by type (supplemental oxygen therapy via low-flow nasal cannula or positive airway pressure [PAP] via high-flow nasal cannula, continuous positive airway pressure, or biphasic positive airway pressure at admission and discharge) and 2) daytime and nighttime NIRI outcome-reduction, increase, or no change from admission to discharge.

RESULTS

For the total sample (n = 38), daytime vs nighttime NIRI use was significantly different (p < 0.001). At both admission and discharge, supplemental oxygen was the most common NIRI during the day, while PAP was most common at night. From admission to discharge, seven (18%) infants and children had a positive change (reduced NIRI) during the day, while nine (24%) had a positive change at night. At discharge, 11/38 (29%) infants and children required no daytime NIRI, while 4/38 (11%) required no day or night NIRI.

CONCLUSION

NIRI use differs between day and night at PACH admission and discharge for CMC. Reductions in NIRI were achieved during the day and at night from PACH admission to discharge for both infants born prematurely and for children with varied congenital, neurological, or cardiac diagnoses.

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.

Noninvasive Respiratory Support Effects on Sighs in Preterm Infants by Electrical Impedance Tomography

OBJECTIVE

To evaluate differences regarding sigh frequency between noninvasive respiratory support types and to assess regional ventilation distribution, delta Z, and end-expiratory lung impedance differences before and after sighs.

METHODS

Very low-birth-weight infants with gestational ages less than 32 wk were included in the study. Participants were split into two groups: those receiving continuous positive airway pressure and infants receiving high-flow nasal cannula therapy.

RESULTS

The study enrolled 30 infants. The high-flow nasal cannula therapy group had more sighs per 10-min period than infants receiving continuous positive airway pressure (p = 0.016). Ventilation distribution was similar in the anterior and right ventilation distribution compartments pre- and post-sigh (46.30% vs. 45.68% and 54.27% vs. 55.26%, respectively). No statistically significant increase in end-expiratory lung impedance or delta Z was observed in global or separate lung regions (p > 0.05).

CONCLUSION

The study has demonstrated that sighs are more frequent in infants receiving high-flow nasal cannula respiratory support compared to continuous positive airway pressure. Spontaneously occurring sighs on noninvasive respiratory support due to respiratory distress syndrome (RDS) do not increase end-expiratory lung impedance or alter delta Z, and appear to have limited clinical significance.

TRIAL REGISTRATION

Prospectively registered at www.

CLINICALTRIALS

gov , reg. No. NCT04542096, reg. date 01/09/2020.

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.

Heated Humidified High-Flow Nasal Cannula in Children: State of the Art

High-flow nasal cannula (HFNC) therapy is a non-invasive ventilatory support that has gained interest over the last ten years as a valid alternative to nasal continuous positive airway pressure (nCPAP) in children with respiratory failure. Its safety, availability, tolerability, and easy management have resulted its increasing usage, even outside intensive care units. Despite its wide use in daily clinical practice, there is still a lack of guidelines to standardize the use of HFNC. The aim of this review is to summarize current knowledge about the mechanisms of action, safety, clinical effects, and tolerance of HFNC in children, and to propose a clinical practices algorithm for children with respiratory failure.

High-Flow Nasal Cannula Oxygen Therapy: Physiological Mechanisms and Clinical Applications in Children

High-flow nasal cannula (HFNC) oxygen therapy has rapidly become a popular modality of respiratory support in pediatric care. This is undoubtedly due to its ease of use and safety, which allows it to be used in a wide variety of settings, ranging from pediatric intensive care to patients' homes. HFNC devices make it possible to regulate gas flow and temperature, as well as allowing some nebulized drugs to be administered, features very useful in children, in which the balance between therapeutic effectiveness and adherence to treatment is pivotal. Although the physiological effects of HFNC are still under investigation, their mechanisms of action include delivery of fixed concentration of oxygen, generation of positive end-expiratory pressure, reduction of the work of breathing and clearance of the nasopharyngeal dead space, while providing optimal gas conditioning. Nevertheless, current evidence supports the use of HFNC mainly in moderate-to-severe bronchiolitis, whereas for asthma exacerbations and breath sleeping disorders there is a lack of randomized controlled trials comparing HFNC to continuous positive airway pressure (CPAP) and non-invasive ventilation (NIV), which are essentials for the identification of response and non-response predictors. In this regard, the development of clinical guidelines for HFNC, including flow settings, indications, and contraindications is urgently needed.

Comparison of high flow nasal cannula and non-invasive positive pressure ventilation in children with bronchiolitis: A meta-analysis of randomized controlled trials

BACKGROUND

The effects of high-flow nasal cannula (HFNC) compared to non-invasive positive pressure ventilation (NIPPV) on children with bronchiolitis remain unclear.

METHODS

This meta-analysis was performed following the preferred reporting items for systematic reviews and meta-analysis (PRISMA) statement. Randomized controlled trials (RCTs) were identified from a comprehensive search in PubMed, EMBASE, Cochrane Library, and Web of Science without time and language limitations. Primary endpoints include the rate of treatment failure, the rate of need for intubation, and the pediatric intensive care unit (PICU) length of stay.

RESULTS

Five RCTs including 541 children of less than 24 months were enrolled in the meta-analysis. Compared to the NIPPV group, the rate of treatment failure was significantly higher in the HFNC treatment group (I ² = 0.0%, P = 0.574; RR 1.523, 95% CI 1.205 to 1.924, P < 0.001). No significant difference was noted in the need for intubation (I ² = 0.0%, P = 0.431; RR 0.874, 95% CI 0.598 to 1.276, P = 0.485) and the PICU length of stay (I ² = 0.0%, P = 0.568; WMD = -0.097, 95% CI = -0.480 to 0.285, P = 0.618) between the HFNC group and the NIPPV treatment.

CONCLUSION

Compared to the NIPPV group, HFNC therapy was associated with a significantly higher treatment failure rate in children suffering from bronchiolitis. The intubation rate and the PICU length of stay were comparable between the two approaches.

Management of Children with Acute Asthma Attack: A RAND/UCLA Appropriateness Approach

Bronchial asthma is the most frequent chronic disease in children and affects up to 20% of the pediatric population, depending on the geographical area. Asthma symptoms vary over time and in intensity, and acute asthma attack can resolve spontaneously or in response to therapy. The aim of this project was to define the care pathway for pediatric patients who come to the primary care pediatrician or Emergency Room with acute asthmatic access. The project was developed in the awareness that for the management of these patients, broad coordination of interventions in the pre-hospital phase and the promotion of timely and appropriate assistance modalities with the involvement of all health professionals involved are important. Through the application of the RAND method, which obliges to discuss the statements derived from the guidelines, there was a clear increase in the concordance in the behavior on the management of acute asthma between primary care pediatricians and hospital pediatricians. The RAND method was found to be useful for the selection of good practices forming the basis of an evidence-based approach, and the results obtained form the basis for further interventions that allow optimizing the care of the child with acute asthma attack at the family and pediatric level. An important point of union between the primary care pediatrician and the specialist hospital pediatrician was the need to share spirometric data, also including the use of new technologies such as teleconsultation. Monitoring the progress of asthma through spirometry could allow the pediatrician in the area to intervene early by modifying the maintenance therapy and help the patient to achieve good control of the disease.

The efficacy and safety of high-flow nasal cannula therapy in patients with COPD and type II respiratory failure: a meta-analysis and systematic review

Background

High-flow nasal cannula (HFNC) and noninvasive ventilation (NIV) have been used for the treatment of COPD and respiratory failure in clinical settings. We aimed to evaluate the efficacy and safety of HFNC therapy in patients with COPD and type II respiratory failure, to provide evidence to the clinical COPD management.

Methods

We searched Cochrane et al. databases up to Dec 31, 2020 for randomized controlled trials (RCTs) on the use of HFNC therapy in patients with COPD and type II respiratory failure. Two researchers independently screened the literature according to the inclusion and exclusion criteria, and evaluated the quality of the literature and extracted data. We used Revman5.3 software for statistical analysis of collected data.

Results

A total of 6 RCTs involving 525 COPD and type II respiratory failure patients. Meta-analyses indicated that compared with NIV, HFNC could significantly reduce PaCO₂ level (MD = − 2.64, 95% CI (− 3.12 to − 2.15)), length of hospital stay ((MD = – 1.19, 95 CI (− 2.23 to − 0.05)), the incidence of nasal facial skin breakdown ((OR = 0.11, 95% CI (0.03–0.41)). And there were no significant differences between the two groups in PaO₂ ((MD = 2.92, 95% CI (− 0.05 to 5.90)), incidence of tracheal intubation ((OR = 0.74, 95% CI (0.34–1.59)) and mortality (OR = 0.77, 95% CI (0.28–2.11)).

Conclusions

HFNC is more advantageous over NIV in the treatment of COPD and type II respiratory failure. Future studies with larger sample size and strict design are needed to further elucidate the role of HFNC in COPD and respiratory failure.

Subcutaneous emphysema of the neck as a complication of high flow nasal cannula therapy in children: a case report

High Flow Nasal Cannula (HFNC) is a noninvasive technique for respiratory support increasingly used in the pediatric wards for the management of respiratory failure. Few data are reported about the safety of HFNC. We describe the case of a 3-months-old infant admitted for acute bronchiolitis Respiratory Syncyctial Virus-related and treated with HFNC for severe respiratory distress. 12 hours after the beginning of HFNC a subcutaneous swelling of the neck, attributable to subcutaneous emphysema, became clinically evident. Radiological imaging showed pneumomediastinum with air leaking up to the neck. Patient was moved to PICU where he further worsened due to a mediastinal shift requiring drainage and mechanical ventilation. He was then progressively weaned from ventilation and was discharged from the hospital. Pneumomediastinum may occur during HFNC, particularly in moderate-severe cases of acute bronchiolitis. Patients undergoing HFNC should be strictly monitored in order to promptly recognize this complication and treat the child appropriately.

Enteral Feeding for Children on Bilevel Positive Pressure Ventilation for Status Asthmaticus

A retrospective data analysis was conducted to evaluate enteral nutrition practices for children admitted with status asthmaticus in a single-center pediatric intensive care unit. Of 406 charts, 315 were analyzed (63% male); 135 on bilevel positive airway pressure ventilation (BIPAP) and 180 on simple mask. Overall median age and weight were 6.0 (interquartile range [IQR]: 6.0) years and 24.8 (IQR: 20.8) kg, respectively. All children studied were on full feeds while still on BIPAP and simple mask; 99.3 and 100% were fed per oral, respectively. Median time to initiation of feeds and full feeds was longer in the BIPAP group, 11.0 (IQR: 20) and 23.0 hours (IQR: 26), versus simple mask group, 4.3 (IQR: 7) and 12.0 hours (IQR: 15), p  = 0.001. The results remained similar after adjusting for gender, weight, clinical asthma score at admission, use of adjunct therapy, and duration of continuous albuterol. By 24 hours, 81.5% of patients on BIPAP and 96.6% on simple mask were started on feeds. Compared with simple mask, patients on BIPAP were sicker with median asthma score at admission of 4 (IQR: 2) versus 3 (IQR: 2) on simple mask, requiring more adjunct therapy (80.0 vs. 43.9%), and a longer median length of therapy of 41.0 (IQR: 41) versus 20.0 hours (IQR: 29), respectively, p  = 0.001. There were no complications such as aspiration pneumonia, and none required invasive mechanical ventilation in either group. Enteral nutrition was effectively and safely initiated and continued for children admitted with status asthmaticus, including those on noninvasive bilevel ventilation therapy.

High-flow nasal cannulae for respiratory support in adult intensive care patients

BACKGROUND

High-flow nasal cannulae (HFNC) deliver high flows of blended humidified air and oxygen via wide-bore nasal cannulae and may be useful in providing respiratory support for adults experiencing acute respiratory failure, or at risk of acute respiratory failure, in the intensive care unit (ICU). This is an update of an earlier version of the review.

OBJECTIVES

To assess the effectiveness of HFNC compared to standard oxygen therapy, or non-invasive ventilation (NIV) or non-invasive positive pressure ventilation (NIPPV), for respiratory support in adults in the ICU.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, CINAHL, Web of Science, and the Cochrane COVID-19 Register (17 April 2020), clinical trial registers (6 April 2020) and conducted forward and backward citation searches.

SELECTION CRITERIA

We included randomized controlled studies (RCTs) with a parallel-group or cross-over design comparing HFNC use versus other types of non-invasive respiratory support (standard oxygen therapy via nasal cannulae or mask; or NIV or NIPPV which included continuous positive airway pressure and bilevel positive airway pressure) in adults admitted to the ICU.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures as expected by Cochrane.

MAIN RESULTS

We included 31 studies (22 parallel-group and nine cross-over designs) with 5136 participants; this update included 20 new studies. Twenty-one studies compared HFNC with standard oxygen therapy, and 13 compared HFNC with NIV or NIPPV; three studies included both comparisons. We found 51 ongoing studies (estimated 12,807 participants), and 19 studies awaiting classification for which we could not ascertain study eligibility information. In 18 studies, treatment was initiated after extubation. In the remaining studies, participants were not previously mechanically ventilated. HFNC versus standard oxygen therapy HFNC may lead to less treatment failure as indicated by escalation to alternative types of oxygen therapy (risk ratio (RR) 0.62, 95% confidence interval (CI) 0.45 to 0.86; 15 studies, 3044 participants; low-certainty evidence). HFNC probably makes little or no difference in mortality when compared with standard oxygen therapy (RR 0.96, 95% CI 0.82 to 1.11; 11 studies, 2673 participants; moderate-certainty evidence). HFNC probably results in little or no difference to cases of pneumonia (RR 0.72, 95% CI 0.48 to 1.09; 4 studies, 1057 participants; moderate-certainty evidence), and we were uncertain of its effect on nasal mucosa or skin trauma (RR 3.66, 95% CI 0.43 to 31.48; 2 studies, 617 participants; very low-certainty evidence). We found low-certainty evidence that HFNC may make little or no difference to the length of ICU stay according to the type of respiratory support used (MD 0.12 days, 95% CI -0.03 to 0.27; 7 studies, 1014 participants). We are uncertain whether HFNC made any difference to the ratio of partial pressure of arterial oxygen to the fraction of inspired oxygen (PaO2/FiO2) within 24 hours of treatment (MD 10.34 mmHg, 95% CI -17.31 to 38; 5 studies, 600 participants; very low-certainty evidence). We are uncertain whether HFNC made any difference to short-term comfort (MD 0.31, 95% CI -0.60 to 1.22; 4 studies, 662 participants, very low-certainty evidence), or to long-term comfort (MD 0.59, 95% CI -2.29 to 3.47; 2 studies, 445 participants, very low-certainty evidence). HFNC versus NIV or NIPPV We found no evidence of a difference between groups in treatment failure when HFNC were used post-extubation or without prior use of mechanical ventilation (RR 0.98, 95% CI 0.78 to 1.22; 5 studies, 1758 participants; low-certainty evidence), or in-hospital mortality (RR 0.92, 95% CI 0.64 to 1.31; 5 studies, 1758 participants; low-certainty evidence). We are very uncertain about the effect of using HFNC on incidence of pneumonia (RR 0.51, 95% CI 0.17 to 1.52; 3 studies, 1750 participants; very low-certainty evidence), and HFNC may result in little or no difference to barotrauma (RR 1.15, 95% CI 0.42 to 3.14; 1 study, 830 participants; low-certainty evidence). HFNC may make little or no difference to the length of ICU stay (MD -0.72 days, 95% CI -2.85 to 1.42; 2 studies, 246 participants; low-certainty evidence). The ratio of PaO2/FiO2 may be lower up to 24 hours with HFNC use (MD -58.10 mmHg, 95% CI -71.68 to -44.51; 3 studies, 1086 participants; low-certainty evidence). We are uncertain whether HFNC improved short-term comfort when measured using comfort scores (MD 1.33, 95% CI 0.74 to 1.92; 2 studies, 258 participants) and responses to questionnaires (RR 1.30, 95% CI 1.10 to 1.53; 1 study, 168 participants); evidence for short-term comfort was very low certainty. No studies reported on nasal mucosa or skin trauma.

AUTHORS' CONCLUSIONS

HFNC may lead to less treatment failure when compared to standard oxygen therapy, but probably makes little or no difference to treatment failure when compared to NIV or NIPPV. For most other review outcomes, we found no evidence of a difference in effect. However, the evidence was often of low or very low certainty. We found a large number of ongoing studies; including these in future updates could increase the certainty or may alter the direction of these effects.

High-Flow Nasal Cannula Therapy in Children With Acute Respiratory Distress With Hypoxia in A Pediatric Intensive Care UnitA Single Center Experience

Aim: High-flow nasal cannulas (HFNCs) show potential in the application of positive pressure, improving gas exchange, and decreasing work of breathing in patients with acute respiratory distress. The aims of this study were to elucidate the indications for HFNC therapy in children of all ages and diagnoses, and to evaluate the efficacy and risk factors for failure of HFNC therapy in children with acute respiratory distress with hypoxia in a pediatric intensive care unit. Methods: We conducted this retrospective cohort study at a tertiary pediatric intensive care unit between January 1, 2018 and December 31, 2020. All children, from 1 month to 18 years of age, with acute respiratory distress with hypoxia and HFNC therapy were eligible. The clinical data were reviewed. Results: One hundred and two children met the eligibility criteria for the study, of whom 57 (55.9%) were male, and the mean age was 7.00 6.79 years. Seventy-eight (76.5%) of the children had underlying disorders. The most common indications for the use of HFNC therapy were pneumonia (40, 39.2%), sepsis-related respiratory distress (17, 16.7%), and bronchiolitis (16, 15.7%). The failure rate was 15.7% (16 of 102 children). Higher initial and maximum fraction of inspiration O2 levels and lower initial and lowest SpO2/FiO2 (S/F) ratio were early and possible signs of failure requiring escalation of respiratory support. Conclusion: In our population, we found that HFNC therapy could be initiated as the first-line therapy for various etiologies of acute respiratory distress with hypoxia in a pediatric intensive care unit and for all age groups.

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.

Intensive Care Unit Utilization After Adoption of a Ward-Based High-Flow Nasal Cannula Protocol

BACKGROUND

Hospitals are increasingly adopting ward-based high-flow nasal cannula (HFNC) protocols that allow HFNC treatment of bronchiolitis outside of the intensive care unit (ICU). Our objective was to determine whether adoption of a ward-based HFNC protocol reduces ICU utilization.

METHODS

We examined a retrospective cohort of infants aged 3 to 24 months hospitalized with bronchiolitis at hospitals in the Pediatric Health Information System database. The study exposure was adoption of a ward-based HFNC protocol, measured by direct contact with pediatric hospital medicine leaders at each hospital. All analyses utilized an interrupted time series approach. The primary analysis compared outcomes three respiratory seasons before and three respiratory seasons after HFNC adoption, among adopting hospitals. Supplementary analysis 1 mirrored the primary analysis with the exception that the first season after adoption was censored. In supplementary analysis 2, effects among nonadopting hospitals were subtracted from effects measured among adopting hospitals.

RESULTS

Of 44 contacted hospitals, 41 replied (93% response rate), of which 18 were categorized as non-adopting hospitals and 12 were categorized as adopting hospitals. Included ward-based HFNC protocols were adopted between the 2010-2011 and 2015-2016 respiratory seasons. The primary analysis included 26,253 bronchiolitis encounters and measured immediate increases in the proportion of patients admitted to the ICU (absolute difference, 3.1%; 95% CI, 2.8%-3.4%) and ICU length of stay (absolute difference, 9.1 days per 100 patients; 95% CI, 5.1-13.2). Both supplementary analyses yielded similar findings.

CONCLUSION

Early protocols for ward-based HFNC were paradoxically associated with increased ICU utilization.

Non-invasive respiratory support for the management of transient tachypnea of the newborn

BACKGROUND

Transient tachypnea of the newborn (TTN) is characterized by tachypnea and signs of respiratory distress. Transient tachypnea typically appears within the first two hours of life in term and late preterm newborns. Supportive management might be sufficient. Non-invasive (i.e. without endotracheal intubation) respiratory support may, however, be administered to reduce respiratory distress during TTN. In addition, non-invasive respiratory support might improve clearance of lung liquid thus reducing the effort required to breathe, improving respiratory distress and potentially reducing the duration of tachypnea.

OBJECTIVES

To assess benefits and harms of non-invasive respiratory support for the management of transient tachypnea of the newborn.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2019, Issue 2), MEDLINE (1996 to 19 February 2019), Embase (1980 to 19 February 2019) and CINAHL (1982 to 19 February 2019). We applied no language restrictions. We searched clinical trial registries for ongoing studies.

SELECTION CRITERIA

Randomized controlled trials, quasi-randomized controlled trials and cluster trials on non-invasive respiratory support provided to infants born at 34 weeks' gestational age or more and less than three days of age with transient tachypnea of the newborn.

DATA COLLECTION AND ANALYSIS

For each of the included trials, two review authors independently extracted data (e.g. number of participants, birth weight, gestational age, duration of oxygen therapy, need for continuous positive airway pressure [CPAP] and need for mechanical ventilation, duration of mechanical ventilation, etc.) and assessed the risk of bias (e.g. adequacy of randomization, blinding, completeness of follow-up). The primary outcomes considered in this review were need for mechanical ventilation and pneumothorax. We used the GRADE approach to assess the certainty of evidence.

MAIN RESULTS

We included three trials (150 infants) comparing either CPAP to free-flow oxygen, nasal intermittent mandatory ventilation to nasal CPAP, or nasal high-frequency percussive ventilation versus nasal CPAP. Due to these different comparisons and to high clinical heterogeneity in the baseline clinical characteristics, we did not pool the three studies. The use of CPAP versus free oxygen did not improve the primary outcomes of this review: need for mechanical ventilation (risk ratio [RR] 0.30, 95% confidence interval [CI] 0.01 to 6.99; 1 study, 64 participants); and pneumothorax (not estimable, no cases occurred). Among secondary outcomes, CPAP reduced the duration of tachypnea as compared to free oxygen (mean difference [MD] -21.10 hours, 95% CI -22.92 to -19.28; 1 study, 64 participants). Nasal intermittent ventilation did not reduce the need for mechanical ventilation as compared with CPAP (RR 4.00, 95% CI 0.49 to 32.72; 1 study, 40 participants) or the incidence of pneumothorax (RR 1.00, 95% CI 0.07 to 14.90; 1 study, 40 participants); duration of tachypnea did not differ (MD 4.30, 95% CI -19.14 to 27.74; 1 study, 40 participants). In the study comparing nasal high-frequency ventilation to CPAP, no cases of mechanical ventilation of pneumothorax occurred (not estimable; 1 study, 46 participants); duration of tachypnea was reduced in the nasal high-frequency ventilation group (MD -4.53, 95% CI -5.64 to -3.42; 1 study, 46 participants). The quality of the evidence was very low due to the imprecision of the estimates and unclear risk of bias for detection bias and high risk of bias for reporting bias. Tests for heterogeneity were not applicable for any of the analyses as no studies were pooled. Two trials are ongoing.

AUTHORS' CONCLUSIONS

There is insufficient evidence to establish the benefit and harms of non-invasive respiratory support in the management of transient tachypnea of the newborn. Though two of the included trials showed a shorter duration of tachypnea, clinically relevant outcomes did not differ amongst the groups. Given the limited and low quality of the evidence available, it was impossible to determine whether non-invasive respiratory support was safe or effective for the treatment of transient tachypnea of the newborn.

Multicentre, randomised trial to investigate early nasal high-flow therapy in paediatric acute hypoxaemic respiratory failure: a protocol for a randomised controlled trial-a Paediatric Acute respiratory Intervention Study (PARIS 2)

INTRODUCTION

Acute hypoxaemic respiratory failure (AHRF) in children is the most frequent reason for non-elective hospital admission. During the initial phase, AHRF is a clinical syndrome defined for the purpose of this study by an oxygen requirement and caused by pneumonia, lower respiratory tract infections, asthma or bronchiolitis. Up to 20% of these children with AHRF can rapidly deteriorate requiring non-invasive or invasive ventilation. Nasal high-flow (NHF) therapy has been used by clinicians for oxygen therapy outside intensive care settings to prevent escalation of care. A recent randomised trial in infants with bronchiolitis has shown that NHF therapy reduces the need to escalate therapy. No similar data is available in the older children presenting with AHRF. In this study we aim to investigate in children aged 1 to 4 years presenting with AHRF if early NHF therapy compared with standard-oxygen therapy reduces hospital length of stay and if this is cost-effective compared with standard treatment.

METHODS AND ANALYSIS

The study design is an open-labelled randomised multicentre trial comparing early NHF and standard-oxygen therapy and will be stratified by sites and into obstructive and non-obstructive groups. Children aged 1 to 4 years (n=1512) presenting with AHRF to one of the participating emergency departments will be randomly allocated to NHF or standard-oxygen therapy once the eligibility criteria have been met (oxygen requirement with transcutaneous saturation <92%/90% (dependant on hospital standard threshold), diagnosis of AHRF, admission to hospital and tachypnoea ≥35 breaths/min). Children in the standard-oxygen group can receive rescue NHF therapy if escalation is required. The primary outcome is hospital length of stay. Secondary outcomes will include length of oxygen therapy, proportion of intensive care admissions, healthcare resource utilisation and associated costs. Analyses will be conducted on an intention-to-treat basis.

ETHICS AND DISSEMINATION

Ethics approval has been obtained in Australia (HREC/15/QRCH/159) and New Zealand (HDEC 17/NTA/135). The trial commenced recruitment in December 2017. The study findings will be submitted for publication in a peer-reviewed journal and presented at relevant conferences. Authorship of all publications will be decided by mutual consensus of the research team.

TRIAL REGISTRATION NUMBER

ACTRN12618000210279.

Pulmonary Barotrauma Following Nasal High-Flow Therapy in a Patient with Bronchiolitis Obliterans Syndrome

Patient: Female, 41

Final Diagnosis: Pulmonary barotrauma

Symptoms: Dyspnea

Medication: —

Clinical Procedure: High-flow nasal cannula

Specialty: Pulmonology

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.

HIGH-FLOW NASAL CANNULA POST-TRACHEAL EXTUBATION IN A CHILD WITH UPPER AIRWAY OBSTRUCTION: CASE REPORT

OBJECTIVE

To report a case of a patient who required tracheal intubation in a pediatric emergency department due to acute laryngitis and that, after the planned extubation, has successfully used the high-flow nasal cannula, which possibly prevented extubation failure.

CASE DESCRIPTION

A male 8-month-old child was admitted to the pediatric emergency room with acute respiratory distress due to a high airway obstruction secondary to severe acute laryngitis. He was immediately intubated and referred to the pediatric intensive care unit. He presented extubation failure due to a significant laryngeal edema evidenced by bronchoscopy. In the second attempt to extubate, he presented respiratory distress, but, after the use of the high-flow nasal cannula, he became stable, reducing the heart and respiratory frequencies, and the extubation was successful.

COMMENTS

The use of the high-flow nasal cannula was effective and presented good response in this patient with acute laryngitis, suggesting that it is a possible adjuvant for the treatment, avoiding worsening respiratory conditions and the need for reintubation.

FIRST-line support for Assistance in Breathing in Children (FIRST-ABC): a multicentre pilot randomised controlled trial of high-flow nasal cannula therapy versus continuous positive airway pressure in paediatric critical care

BACKGROUND

Although high-flow nasal cannula therapy (HFNC) has become a popular mode of non-invasive respiratory support (NRS) in critically ill children, there are no randomised controlled trials (RCTs) comparing it with continuous positive airway pressure (CPAP). We performed a pilot RCT to explore the feasibility, and inform the design and conduct, of a future large pragmatic RCT comparing HFNC and CPAP in paediatric critical care.

METHODS

In this multi-centre pilot RCT, eligible patients were recruited to either Group A (step-up NRS) or Group B (step-down NRS). Participants were randomised (1:1) using sealed opaque envelopes to either CPAP or HFNC as their first-line mode of NRS. Consent was sought after randomisation in emergency situations. The primary study outcomes were related to feasibility (number of eligible patients in each group, proportion of eligible patients randomised, consent rate, and measures of adherence to study algorithms). Data were collected on safety and a range of patient outcomes in order to inform the choice of a primary outcome measure for the future RCT.

RESULTS

Overall, 121/254 eligible patients (47.6%) were randomised (Group A 60%, Group B 44.2%) over a 10-month period (recruitment rate for Group A, 1 patient/site/month; Group B, 2.8 patients/site/month). In Group A, consent was obtained in 29/33 parents/guardians approached (87.9%), while in Group B 84/118 consented (71.2%). Intention-to-treat analysis included 113 patients (HFNC 59, CPAP 54). Most reported adverse events were mild/moderate (HFNC 8/59, CPAP 9/54). More patients switched treatment from HFNC to CPAP (Group A: 7/16, 44%; Group B: 9/43, 21%) than from CPAP to HFNC (Group A: 3/13, 23%; Group B: 5/41, 12%). Intubation occurred within 72 h in 15/59 (25.4%) of HFNC patients and 10/54 (18.5%) of CPAP patients (p = 0.38). HFNC patients experienced fewer ventilator-free days at day 28 (Group A: 19.6 vs. 23.5; Group B: 21.8 vs. 22.2).

CONCLUSIONS

Our pilot trial confirms that, following minor changes to consent procedures and treatment algorithms, it is feasible to conduct a large national RCT of non-invasive respiratory support in the paediatric critical care setting in both step-up and step-down NRS patients.

TRIAL REGISTRATION

clinicaltrials.gov, NCT02612415 . Registered on 23 November 2015.

Past, Present and Future Approaches to the Prevention and Treatment of Respiratory Syncytial Virus Infection in Children

INTRODUCTION

The REGAL (RSV Evidence - A Geographical Archive of the Literature) series has provided a comprehensive review of the published evidence in the field of respiratory syncytial virus (RSV) in Western countries over the last 20 years. This seventh and final publication covers the past, present and future approaches to the prevention and treatment of RSV infection among infants and children.

METHODS

A systematic review was undertaken of publications between January 1, 1995 and December 31, 2017 across PubMed, Embase and The Cochrane Library. Studies reporting data on the effectiveness and tolerability of prophylactic and therapeutic agents for RSV infection were included. Study quality and strength of evidence (SOE) were graded using recognized criteria. A further nonsystematic search of the published literature and Clinicaltrials.gov on antiviral therapies and RSV vaccines currently in development was also undertaken.

RESULTS

The systematic review identified 1441 studies of which 161 were included. Management of RSV remains centered around prophylaxis with the monoclonal antibody palivizumab, which has proven effective in reducing RSV hospitalization (RSVH) in preterm infants < 36 weeks' gestational age (72% reduction), children with bronchopulmonary dysplasia (65% reduction), and infants with hemodynamically significant congenital heart disease (53% reduction) (high SOE). Palivizumab has also shown to be effective in reducing recurrent wheezing following RSVH (high SOE). Treatment of RSV with ribavirin has conflicting success (moderate SOE). Antibodies with increased potency and extended half-life are currently entering phase 3 trials. There are approximately 15 RSV vaccines in clinical development targeting the infant directly or indirectly via the mother.

CONCLUSION

Palivizumab remains the only product licensed for RSV prophylaxis, and only available for high-risk infants. For the general population, there are several promising vaccines and monoclonal antibodies in various stages of clinical development, with the aim to significantly reduce the global healthcare impact of this common viral infection.

FUNDING

AbbVie.

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.

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.

Recommendations for mechanical ventilation of critically ill children from the Paediatric Mechanical Ventilation Consensus Conference (PEMVECC)

Purpose

Much of the common practice in paediatric mechanical ventilation is based on personal experiences and what paediatric critical care practitioners have adopted from adult and neonatal experience. This presents a barrier to planning and interpretation of clinical trials on the use of specific and targeted interventions. We aim to establish a European consensus guideline on mechanical ventilation of critically children.

Methods

The European Society for Paediatric and Neonatal Intensive Care initiated a consensus conference of international European experts in paediatric mechanical ventilation to provide recommendations using the Research and Development/University of California, Los Angeles, appropriateness method. An electronic literature search in PubMed and EMBASE was performed using a combination of medical subject heading terms and text words related to mechanical ventilation and disease-specific terms.

Results

The Paediatric Mechanical Ventilation Consensus Conference (PEMVECC) consisted of a panel of 15 experts who developed and voted on 152 recommendations related to the following topics: (1) general recommendations, (2) monitoring, (3) targets of oxygenation and ventilation, (4) supportive measures, (5) weaning and extubation readiness, (6) normal lungs, (7) obstructive diseases, (8) restrictive diseases, (9) mixed diseases, (10) chronically ventilated patients, (11) cardiac patients and (12) lung hypoplasia syndromes. There were 142 (93.4%) recommendations with “strong agreement”. The final iteration of the recommendations had none with equipoise or disagreement.

Conclusions

These recommendations should help to harmonise the approach to paediatric mechanical ventilation and can be proposed as a standard-of-care applicable in daily clinical practice and clinical research.

Electronic supplementary material

The online version of this article (doi:10.1007/s00134-017-4920-z) contains supplementary material, which is available to authorized users.

FIRST-line support for Assistance in Breathing in Children (FIRST-ABC): protocol for a multicentre randomised feasibility trial of non-invasive respiratory support in critically ill children

INTRODUCTION

Over 18 000 children are admitted annually to UK paediatric intensive care units (PICUs), of whom nearly 75% receive respiratory support (invasive and/or non-invasive). Continuous positive airway pressure (CPAP) has traditionally been used to provide first-line non-invasive respiratory support (NRS) in PICUs; however, high-flow nasal cannula therapy (HFNC), a novel mode of NRS, has recently gained popularity despite the lack of high-quality trial evidence to support its effectiveness. This feasibility study aims to inform the design and conduct of a future definitive randomised clinical trial (RCT) comparing the two modes of respiratory support.

METHODS AND ANALYSIS

We will conduct a three-centre randomised feasibility study over 12 months. Patients admitted to participating PICUs who satisfy eligibility criteria will be recruited to either group A (primary respiratory failure) or group B (postextubation). Consent will be obtained from parents/guardians prior to randomisation in 'planned' group B, and deferred in emergency situations (group A and 'rescue' group B). Participants will be randomised (1:1) to either CPAP or HFNC using sealed, opaque envelopes, from a computer-generated randomisation sequence with variable block sizes. The study protocol specifies algorithms for the initiation, maintenance and weaning of HFNC and CPAP. The primary outcomes are related to feasibility, including the number of eligible patients in each group, feasibility of randomising >50% of eligible patients and measures of adherence to the treatment protocols. Data will also be collected on patient outcomes (eg, mortality and length of PICU stay) to inform the selection of an appropriate outcome measure in a future RCT. We aim to recruit 120 patients to the study.

ETHICS AND DISSEMINATION

Ethical approval was granted by the National Research Ethics Service Committee North East-Tyne&Wear South (15/NE/0296). Study findings will be disseminated through peer-reviewed journals, national and international conferences.

TRIALS REGISTRATION NUMBER

NCT02612415; pre-results.

High-flow nasal cannulae for respiratory support in adult intensive care patients

BACKGROUND

High-flow nasal cannulae (HFNC) deliver high flows of blended humidified air and oxygen via wide-bore nasal cannulae and may be useful in providing respiratory support for adult patients experiencing acute respiratory failure in the intensive care unit (ICU).

OBJECTIVES

We evaluated studies that included participants 16 years of age and older who were admitted to the ICU and required treatment with HFNC. We assessed the safety and efficacy of HFNC compared with comparator interventions in terms of treatment failure, mortality, adverse events, duration of respiratory support, hospital and ICU length of stay, respiratory effects, patient-reported outcomes, and costs of treatment.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 3), MEDLINE, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), Embase, Web of Science, proceedings from four conferences, and clinical trials registries; and we handsearched reference lists of relevant studies. We conducted searches from January 2000 to March 2016 and reran the searches in December 2016. We added four new studies of potential interest to a list of 'Studies awaiting classification' and will incorporate them into formal review findings during the review update.

SELECTION CRITERIA

We included randomized controlled studies with a parallel or cross-over design comparing HFNC use in adult ICU patients versus other forms of non-invasive respiratory support (low-flow oxygen via nasal cannulae or mask, continuous positive airway pressure (CPAP), and bilevel positive airway pressure (BiPAP)).

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for inclusion, extracted data, and assessed risk of bias.

MAIN RESULTS

We included 11 studies with 1972 participants. Participants in six studies had respiratory failure, and in five studies required oxygen therapy after extubation. Ten studies compared HFNC versus low-flow oxygen devices; one of these also compared HFNC versus CPAP, and another compared HFNC versus BiPAP alone. Most studies reported randomization and allocation concealment inadequately and provided inconsistent details of outcome assessor blinding. We did not combine data for CPAP and BiPAP comparisons with data for low-flow oxygen devices; study data were insufficient for separate analysis of CPAP and BiPAP for most outcomes. For the primary outcomes of treatment failure (1066 participants; six studies) and mortality (755 participants; three studies), investigators found no differences between HFNC and low-flow oxygen therapies (risk ratio (RR), Mantel-Haenszel (MH), random-effects 0.79, 95% confidence interval (CI) 0.49 to 1.27; and RR, MH, random-effects 0.63, 95% CI 0.38 to 1.06, respectively). We used the GRADE approach to downgrade the certainty of this evidence to low because of study risks of bias and different participant indications. Reported adverse events included nosocomial pneumonia, oxygen desaturation, visits to general practitioner for respiratory complications, pneumothorax, acute pseudo-obstruction, cardiac dysrhythmia, septic shock, and cardiorespiratory arrest. However, single studies reported adverse events, and we could not combine these findings; one study reported fewer episodes of oxygen desaturation with HFNC but no differences in all other reported adverse events. We downgraded the certainty of evidence for adverse events to low because of limited data. Researchers noted no differences in ICU length of stay (mean difference (MD), inverse variance (IV), random-effects 0.15, 95% CI -0.03 to 0.34; four studies; 770 participants), and we downgraded quality to low because of study risks of bias and different participant indications. We found no differences in oxygenation variables: partial pressure of arterial oxygen (PaO2)/fraction of inspired oxygen (FiO2) (MD, IV, random-effects 7.31, 95% CI -23.69 to 41.31; four studies; 510 participants); PaO2 (MD, IV, random-effects 2.79, 95% CI -5.47 to 11.05; three studies; 355 participants); and oxygen saturation (SpO2) up to 24 hours (MD, IV, random-effects 0.72, 95% CI -0.73 to 2.17; four studies; 512 participants). Data from two studies showed that oxygen saturation measured after 24 hours was improved among those treated with HFNC (MD, IV, random-effects 1.28, 95% CI 0.02 to 2.55; 445 participants), but this difference was small and was not clinically significant. Along with concern about risks of bias and differences in participant indications, review authors noted a high level of unexplained statistical heterogeneity in oxygenation effect estimates, and we downgraded the quality of evidence to very low. Meta-analysis of three comparable studies showed no differences in carbon dioxide clearance among those treated with HFNC (MD, IV, random-effects -0.75, 95% CI -2.04 to 0.55; three studies; 590 participants). Two studies reported no differences in atelectasis; we did not combine these findings. Data from six studies (867 participants) comparing HFNC versus low-flow oxygen showed no differences in respiratory rates up to 24 hours according to type of oxygen delivery device (MD, IV, random-effects -1.51, 95% CI -3.36 to 0.35), and no difference after 24 hours (MD, IV, random-effects -2.71, 95% CI -7.12 to 1.70; two studies; 445 participants). Improvement in respiratory rates when HFNC was compared with CPAP or BiPAP was not clinically important (MD, IV, random-effects -0.89, 95% CI -1.74 to -0.05; two studies; 834 participants). Results showed no differences in patient-reported measures of comfort according to oxygen delivery devices in the short term (MD, IV, random-effects 0.14, 95% CI -0.65 to 0.93; three studies; 462 participants) and in the long term (MD, IV, random-effects -0.36, 95% CI -3.70 to 2.98; two studies; 445 participants); we downgraded the certainty of this evidence to low. Six studies measured dyspnoea on incomparable scales, yielding inconsistent study data. No study in this review provided data on positive end-expiratory pressure measured at the pharyngeal level, work of breathing, or cost comparisons of treatment.

AUTHORS' CONCLUSIONS

We were unable to demonstrate whether HFNC was a more effective or safe oxygen delivery device compared with other oxygenation devices in adult ICU patients. Meta-analysis could be performed for few studies for each outcome, and data for comparisons with CPAP or BiPAP were very limited. In addition, we identified some risks of bias among included studies, differences in patient groups, and high levels of statistical heterogeneity for some outcomes, leading to uncertainty regarding the results of our analysis. Consequently, evidence is insufficient to show whether HFNC provides safe and efficacious respiratory support for adult ICU patients.

Comparison of CPAP and HFNC in Management of Bronchiolitis in Infants and Young Children

Continuous positive airway pressure (CPAP) has been used in infants with bronchiolitis for decades. Recently, high flow nasal cannula (HFNC) therapy was introduced We conducted a retrospective study of treatment with CPAP vs. HFNC between 2013 and 2015, comparing the development in respiratory rate, fraction of inspired oxygen (FiO2) and heart rate, treatment failure, duration of treatment, and length of hospital stay. A sample size of 49 children were included. Median age was 1.9 months. Median baseline pCO₂ was 7.4 kPa in both groups, respiratory rate per minute was 57 vs. 58 (CPAP vs. HFNC). Respiratory rate decreased faster in the CPAP group (p < 0.05). FiO2 decreased in the CPAP group and increased in the HFNC group during the first 12 h, whereafter it decreased in both groups. (p < 0.01). Heart rate development was similar in both groups. Twelve children (55%) changed systems from HFNC to CPAP due to disease progression. There was no difference in length of treatment, hospital stay, or transmission to intensive care unit between the groups. CPAP was more effective than HFNC in decreasing respiratory rate (RR) and FiO2. No differences were observed in length of treatment or complications. Further studies should be conducted to compare the efficacy of the two treatments of bronchiolitis, preferably through prospective randomized trials.

Prospective Multicentre Study on the Epidemiology and Current Therapeutic Management of Severe Bronchiolitis in Spain

Objective. To determine the epidemiology and therapeutic management of patients with severe acute bronchiolitis (AB) admitted to paediatric intensive care units (PICUs) in Spain. Design. Descriptive, prospective, multicentre study. Setting. Sixteen Spanish PICUs. Patients. Patients with severe AB who required admission to any of the participating PICUs over 1 year. Interventions. Both epidemiological variables and medical treatment received were recorded. Results. A total of 262 patients were recruited; 143 were male (54.6%), with median age of 1 month (0–23). Median stay in the PICU was 7 days (1–46). Sixty patients (23%) received no nebuliser treatment, while the rest received a combination of inhalation therapies. One-quarter of patients (24.8%) received corticosteroids and 56.5% antibiotic therapy. High-flow oxygen therapy was used in 14.3% and noninvasive ventilation (NIV) was used in 75.6%. Endotracheal intubation was required in 24.4% of patients. Younger age, antibiotic therapy, and invasive mechanical ventilation (IMV) were risk factors that significantly increased the stay in the PICU. Conclusions. Spanish PICUs continue to routinely use nebulised bronchodilator treatment and corticosteroid therapy. Despite NIV being widely used in this condition, intubation was required in one-quarter of cases. Younger age, antibiotic therapy, and IMV were associated with a longer stay in the PICU.

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.

High flow nasal cannula in children: a literature review

High flow nasal cannula (HFNC) is a relatively new non-invasive ventilation therapy that seems to be well tolerated in children. Recently a marked increase in the use of HFNC has been seen both in paediatric and adult care settings. The aim of this study was to review the current knowledge of HFNC regarding mechanisms of action, safety, clinical effects and tolerance in children beyond the newborn period.We performed a systematic search of the databases PubMed, Medline, EMBASE and Cochrane up to 12th of May 2016. Twenty-six clinical studies including children on HFNC beyond the newborn period with various respiratory diseases hospitalised in an emergency department, paediatric intensive care unit or general ward were included. Five of these studies were interventional studies and 21 were observational studies. Thirteen studies included only children with bronchiolitis, while the other studies included children with various respiratory conditions. Studies including infants hospitalised in a neonatal ward, or adults over 18 years of age, as well as expert reviews, were not systematically evaluated, but discussed if appropriate.The available studies suggest that HFNC is a relatively safe, well-tolerated and feasible method for delivering oxygen to children with few adverse events having been reported. Different mechanisms including washout of nasopharyngeal dead space, increased pulmonary compliance and some degree of distending airway pressure may be responsible for the effect. A positive clinical effect on various respiratory parameters has been observed and studies suggest that HFNC may reduce the work of breathing. Studies including children beyond the newborn period have found that HFNC may reduce the need of continuous positive airway pressure (CPAP) and invasive ventilation, but these studies are observational and have a low level of evidence. There are no international guidelines regarding flow rates and the optimal maximal flow for HFNC is not known, but few studies have used a flow rate higher than 10 L/min for infants.Until more evidence from randomized studies is available, HFNC may be used as a supplementary form of respiratory support in children, but with a critical approach regarding effect and safety, particularly when operated outside of a paediatric intensive care unit.

Pediatric Noninvasive Ventilation

Noninvasive ventilation has been available for many years for use in the pediatric population. Historically, continuous positive airway pressure and bilevel positive airway pressure modes were used for respiratory diseases, including neonatal apnea, bronchiolitis, asthma, and pneumonia. Newer studies suggest that noninvasive ventilation is also an effective and safe mode for support of children with acute respiratory distress syndrome and respiratory failure. The newest type of noninvasive respiratory support is high flow nasal cannula, which has gained popularity in the past few years and its use is being justified in the literature. Studies have shown that these therapies can decrease the need for intubation and ventilation, decrease length of intensive care days, and increase patient comfort. Additional research is needed to support optimal setting selection and recommendations for the use of noninvasive therapies for infants and children.

High-flow nasal cannula oxygen therapy in adults

High-flow nasal cannula (HFNC) oxygen therapy comprises an air/oxygen blender, an active humidifier, a single heated circuit, and a nasal cannula. It delivers adequately heated and humidified medical gas at up to 60 L/min of flow and is considered to have a number of physiological effects: reduction of anatomical dead space, PEEP effect, constant fraction of inspired oxygen, and good humidification. While there have been no big randomized clinical trials, it has been gaining attention as an innovative respiratory support for critically ill patients. Most of the available data has been published in the neonatal field. Evidence with critically ill adults are poor; however, physicians apply it to a variety of patients with diverse underlying diseases: hypoxemic respiratory failure, acute exacerbation of chronic obstructive pulmonary disease, post-extubation, pre-intubation oxygenation, sleep apnea, acute heart failure, patients with do-not-intubate order, and so on. Many published reports suggest that HFNC decreases breathing frequency and work of breathing and reduces needs of escalation of respiratory support in patients with diverse underlying diseases. Some important issues remain to be resolved, such as its indication, timing of starting and stopping HFNC, and escalating treatment. Despite these issues, HFNC oxygen therapy is an innovative and effective modality for the early treatment of adults with respiratory failure with diverse underlying diseases.

High-flow nasal cannula: recommendations for daily practice in pediatrics

High-flow nasal cannula (HFNC) is a relatively new device for respiratory support. In pediatrics, HFNC use continues to increase as the system is easily set up and is well tolerated by patients. The use of nasal cannula adapted to the infant’s nares size to deliver heated and humidified gas at high flow rates has been associated with improvements in washout of nasopharyngeal dead space, lung mucociliary clearance, and oxygen delivery compared with other oxygen delivery systems. HFNC may also create positive pharyngeal pressure to reduce the work of breathing, which positions the device midway between classical oxygen delivery systems, like the high-concentration face mask and continuous positive airway pressure (CPAP) generators. Currently, most of the studies in the pediatric literature suggest the benefits of HFNC therapy only for moderately severe acute viral bronchiolitis. But, the experience with this device in neonatology and adult intensive care may broaden the pediatric indications to include weaning from invasive ventilation and acute asthma. As for any form of respiratory support, HFNC initiation in patients requires close monitoring, whether it be for pre- or inter-hospital transport or in the emergency department or the pediatric intensive care unit.

High-flow nasal cannula therapy for respiratory support in children

BACKGROUND

Respiratory support is a central component of the management of critically ill children. It can be delivered invasively via an endotracheal tube or non-invasively via face mask, nasal mask, nasal cannula or oxygen hood/tent. Invasive ventilation can be damaging to the lungs, and the tendency to use non-invasive forms is growing. However, non-invasive delivery is often poorly tolerated by children. High-flow nasal cannula (HFNC) oxygen delivery is a relatively new therapy that shows the potential to reduce the need for intubation and be better tolerated by children than other non-invasive forms of support. HFNC therapy differs from other non-invasive forms of treatment in that it delivers heated, humidified and blended air/oxygen via nasal cannula at rates > 2 L/kg/min. This allows the user to deliver high concentrations of oxygen and to potentially deliver continuous distending pressure; this treatment often is better tolerated by the child.

OBJECTIVES

To determine whether HFNC therapy is more effective than other forms of non-invasive therapy in paediatric patients who require respiratory support.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (2013, Issue 4); MEDLINE via PubMed (January 1966 to April 2013); EMBASE (January 1980 to April 2013); CINAHL (1982 to April 2013); and LILACS (1982 to April 2013). Abstracts from conference proceedings, theses and dissertations and bibliographical references to relevant studies were also searched. We applied no restriction on language.

SELECTION CRITERIA

We planned to included randomized controlled trials (RCTs) and quas-randomized trials comparing HFNC therapy with other forms of non-invasive respiratory support for children. Non-invasive support encompassed cot, hood or tent oxygen; low-flow nasal cannulae (flow rates ≤ 2 L/min); and continuous positive airway pressure (CPAP) or bilevel positive airway pressure (BiPAP) delivered via facial or nasal mask/cannula. Treatment failure was defined by the need for additional respiratory support. We excluded children with a diagnosis of bronchiolitis.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed all studies for selection and data extraction. We used standard methodological procedures expected by The Cochrane Collaboration.

MAIN RESULTS

Our search yielded 922 records. A total of 109 relevant records were retrieved with reference to our search criteria. After duplicates and irrelevant studies were removed, 69 studies were further scrutinized. Of these, 11 studies involved children. No study matched our inclusion criteria.

AUTHORS' CONCLUSIONS

Based on the results of this review, no evidence is available to allow determination of the safety or effectiveness of HFNC as a form of respiratory support in children.