Place de la ventilation non invasive nasale dans la prise en charge des broncho-alvéolites sévères

Continuous positive airway pressure (CPAP) for acute bronchiolitis in children

BACKGROUND

Acute bronchiolitis is one of the most frequent causes of emergency department visits and hospitalisation in children up to three years of age. There is no specific treatment for bronchiolitis except for supportive treatment, which includes ensuring adequate hydration and oxygen supplementation. Continuous positive airway pressure (CPAP) aims to widen the lungs' peripheral airways, enabling deflation of overdistended lungs in bronchiolitis. Increased airway pressure also prevents the collapse of poorly supported peripheral small airways during expiration. Observational studies report that CPAP is beneficial for children with acute bronchiolitis. This is an update of a review first published in 2015 and updated in 2019.

OBJECTIVES

To assess the efficacy and safety of CPAP compared to no CPAP or sham CPAP in infants and children up to three years of age with acute bronchiolitis.

SEARCH METHODS

We conducted searches of CENTRAL (2021, Issue 7), which includes the Cochrane Acute Respiratory Infections Group Specialised Register, MEDLINE (1946 to August 2021), Embase (1974 to August 2021), CINAHL (1981 to August 2021), and LILACS (1982 to August 2021) in August 2021. We also searched the US National Institutes of Health Ongoing Trials Register ClinicalTrials.gov and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) for completed and ongoing trials on 26 October 2021.

SELECTION CRITERIA

We considered randomised controlled trials (RCTs), quasi-RCTs, cross-over RCTs, and cluster-RCTs evaluating the effect of CPAP in children with acute bronchiolitis.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed study eligibility, extracted data using a structured pro forma, analysed data, and performed meta-analyses. We used the Cochrane risk of bias tool to assess risk of bias in the included studies. We created a summary of the findings table employing GRADEpro GDT software.  MAIN RESULTS: We included three studies with a total of 122 children (62/60 in intervention/control arms) aged up to 12 months investigating nasal CPAP compared with supportive (or 'standard') therapy. We included one new trial (72 children) in the 2019 update that contributed data to the assessment of respiratory rate and the need for mechanical ventilation for this update. We did not identify any new trials for inclusion in the current update. The included studies were single-centre trials conducted in France, the UK, and India. Two studies were parallel-group RCTs, and one study was a cross-over RCT. The evidence provided by the included studies was of low certainty; we made an assessment of high risk of bias for blinding, incomplete outcome data, and selective reporting, and confidence intervals were wide. The effect of CPAP on the need for mechanical ventilation in children with acute bronchiolitis was uncertain due to risk of bias and imprecision around the effect estimate (risk difference -0.01, 95% confidence interval (CI) -0.09 to 0.08; 3 RCTs, 122 children; low certainty evidence). None of the trials measured time to recovery. Limited, low certainty evidence indicated that CPAP decreased respiratory rate (decreased respiratory rate is better) (mean difference (MD) -3.81, 95% CI -5.78 to -1.84; 2 RCTs, 91 children; low certainty evidence). Only one trial measured change in arterial oxygen saturation (increased oxygen saturation is better), and the results were imprecise (MD -1.70%, 95% CI -3.76 to 0.36; 1 RCT, 19 children; low certainty evidence). The effect of CPAP on change in arterial partial carbon dioxide pressure (pCO₂) (decrease in pCO₂ is better) was imprecise (MD -2.62 mmHg, 95% CI -5.29 to 0.05; 2 RCTs, 50 children; low certainty evidence). Duration of hospital stay was similar in both the CPAP and supportive care groups (MD 0.07 days, 95% CI -0.36 to 0.50; 2 RCTs, 50 children; low certainty evidence). Two studies did not report pneumothorax, but pneumothorax did not occur in one study. No studies reported occurrences of deaths. Several outcomes (change in partial oxygen pressure, hospital admission rate (from the emergency department to hospital), duration of emergency department stay, and need for intensive care unit admission) were not reported in the included studies.

AUTHORS' CONCLUSIONS

The use of CPAP did not reduce the need for mechanical ventilation in children with bronchiolitis, although the evidence was of low certainty. Limited, low certainty evidence suggests that breathing improved (a decreased respiratory rate) in children with bronchiolitis who received CPAP; this finding is unchanged from the 2015 review and 2019 update. Due to the limited available evidence, the effect of CPAP in children with acute bronchiolitis is uncertain for our other outcomes. Larger, adequately powered trials are needed to evaluate the effect of CPAP for children with acute bronchiolitis.

Safety and effectiveness of bubble continuous positive airway pressure as respiratory support for bronchiolitis in a pediatric ward

The results of several clinical trials suggest that continuous positive airway pressure (CPAP) for acute bronchiolitis can be more effective than high-flow nasal cannula (HFNC). The use of HFNC involved a minimum reduction (5%) in admissions to the pediatric intensive care unit (PICU) in our hospital. Our main aim was to evaluate its safety and effectiveness as respiratory support for patients with bronchiolitis in a pediatric general ward. A secondary goal was to compare the admissions to PICU and the invasive mechanical ventilation (IMV) rate of patients treated with HFNC and those treated with HFNC/b-CPAP during the 2018-2019 and 2019-2020 epidemic seasons, respectively. Two prospective single-centre observational studies were performed. For the main aim, a cohort study (CS1) was carried out from 1st of November 2019 to 15th of January 2020. Inclusion criteria were children aged up to 3 months with bronchiolitis treated with b-CPAP support when HFNC failed. Epidemiological and clinical parameters were collected before and 60 min after the onset of CPAP and compared between the responder (R) and non-responders (NR) groups. NR was the group that required PICU admission. One hundred fifty-eight patients were admitted to the ward with bronchiolitis and HFNC. Fifty-seven out of one hundred fifty-eight required b-CPAP. No adverse events were observed. Thirty-two out of fifty-seven remained in the general ward (R-group), and 25/57 were admitted to PICU (NR-group). There were statistically significant differences in respiratory rate (RR) and heart rate (HR) between both groups before and after the initiation of b-CPAP, but the multivariable models showed that the main differences were observed after 60 min of therapy (lower HR, RR, BROSJOD score and FiO2 in the R-group). For the secondary aim, another cohort study (CS2) was performed comparing data from a pre-b-CPAP bronchiolitis season (1st of November 2018 to 15th January 2019) and the b-CPAP season (2019-2020). Inclusion criteria in pre-b-CPAP season were children aged up to 3 months admitted to the same general ward with moderate-severe bronchiolitis and with HFNC support. Admissions to PICU during the CPAP season were significantly reduced, without entailing an increase in the rate of IMV.

CONCLUSION

The implementation of b-CPAP for patients with bronchiolitis in a pediatric ward, in whom HFNC fails, is safe and effective and results in a reduction in PICU admissions.

WHAT IS KNOWN

• Bronchiolitis is one of the most frequent respiratory infections in children and one of the leading causes of hospitalization in infants. • Several studies suggest that the use of continuous positive airway pressure (CPAP) for acute bronchiolitis can be more effective than the high flow nasal cannula (HFNC). CPAP is a non-invasive ventilation (NIV) therapy used in patients admitted to pediatric intensive care unit (PICU) with progressive moderate-severe bronchiolitis. There is little experience in the literature on the use of continuous positive airway pressure (CPAP) for acute bronchiolitis in a general ward.

WHAT IS NEW

• CPAP could be safely and effectively used as respiratory support in young infants with moderate-severe bronchiolitis in a general ward and it reduced the rate of patients who required PICU admission. • Patients' heart and respiratory rate and their FiO2 needs in the first 60 minutes may help to decide whether or not to continue the CPAP therapy in a general ward.

Predictive factors of continuous negative extrathoracic pressure management failure in children with moderate to severe respiratory syncytial virus infection

Continuous negative extrathoracic pressure (CNEP) might be beneficial for children with severe respiratory tract infections. However, there are no available data on the predictors of its failure among individuals with respiratory syncytial virus (RSV) infections. Here, we conducted a retrospective cohort study between October 1, 2015 and October 31, 2018 in hospitalized children with moderate to severe symptoms of respiratory syncytial virus (RSV) infections. We divided 45 children requiring CNEP ventilation with a non-fluctuating negative pressure of - 12 cm H2O into two groups. They were classified based on improvement or deterioration of their respiratory disorder under CNEP ventilation (responder group: n = 27, failure group: n = 18). Based on the univariate analysis, the responder and failure groups significantly differed in terms of median age, days elapsed from RSV onset to the initiation of CNEP, white blood cell count (WBC), titer of venous pCO2, body temperature at admission, and modified Wood-Downes Score (mWDS) 6 h after initiating CNEP. Based on a logistic regression analysis adjusted for age < 1 year upon admission, less than 5 days elapsed from RSV onset to the initiation of CNEP, not high value of WBC and body temperature at admission, and high values of mWDS 6 h after initiating CNEP were found to be significant independent risk factors for CNEP ventilation failure. The former two variables were associated with less failure (odds ratio was approximately 5), and the latter two variables are associated with more failure (odds ratio was approximately 8-9). Thus, CNEP could be a valid option for children with moderate to severe RSV infections, especially in those who were aged > 1 year, and specific clinical and laboratory findings.

Emergency room endotracheal intubation in children with bronchiolitis: A cohort study using a multicenter database

BACKGROUND AND AIMS

Bronchiolitis and asthma have a clinical overlap, and it has been shown that pediatric intensive care unit (PICU) patients with asthma undergoing endotracheal intubation in a community hospital emergency room (ER) have a shorter duration of mechanical ventilation (MV) and PICU length of stay (LOS) vs children undergoing intubation in a children's hospital. We aimed to determine if the setting of intubation (community vs children's hospital ER) is associated with the duration of MV and PICU LOS among children with bronchiolitis.

METHODS

With IRB approval, data in the Virtual Pediatric Systems (VPS, LLC) database were queried for bronchiolitis patients <24 months of age admitted to one of 103 predominantly North American PICUs between 1/2009 and 1/2016 who had an endotracheal tube in place at PICU admission. There were no exclusion criteria. Extracted data included ER type (community/external or children's hospital/internal), demographics, and reported comorbidities. Outcomes analyzed were duration of MV and PICU LOS. Multivariable linear regression was used to evaluate if intubation location was independently associated with the outcomes of interest.

RESULTS

Among 1934 patients, median age was 2.0 (IQR: 1.0-4.8) months, 51% were admitted from an external ER, 41% were White, 61% were male, and 28% had ≥1 comorbidity. Median duration of MV was 6.6 (4.6-9.5) days and the median PICU LOS was 7.0 (4.6-10.6) days. Children who underwent endotracheal intubation in a children's hospital ER had a modestly longer duration of MV (6.7 [4.4-9.4] vs 6.5 [5.2-9.6] days, P < .001, Mann-Whitney U) and longer PICU LOS (7.2 [4.8-10.8] vs 6.9 [4.2-10.1] days, P = .004, Mann-Whitney U). After adjusting for confounding variables, we did not observe a significant association between the location of endotracheal intubation and duration of MV or PICU LOS.

CONCLUSION

In this cohort, and unlike outcomes of near-fatal asthma, we observed that clinical outcomes of critical bronchiolitis were similar regardless of location of endotracheal intubation.

[Predictive factors for failure of continuous positive airway pressure treatment in infants with bronchiolitis]

OBJECTIVE

To study the predictive factors for the failure of continuous positive airway pressure (CPAP) treatment in infants with bronchiolitis.

METHODS

A retrospective analysis was performed on the clinical data of 310 hospitalized children (aged 1-12 months) with bronchiolitis treated with CPAP. Their clinical features were compared between the successful treatment group (270 cases) and the failed treatment group (40 cases). A multivariate logistic regression analysis was used to explore the predictive factors for failure of CPAP treatment.

RESULTS

The multivariate logistic regression analysis showed that the score of the Pediatric Risk of Mortality III (PRISM III) ≥10 (OR=13.905), development of atelectasis (OR=12.080), comorbidity of cardiac insufficiency (OR=7.741), and no improvement in oxygenation index (arterial partial pressure of oxygen/fraction of inhaled oxygen, P/F) after 2 hours of CPAP treatment (OR=34.084) were predictive factors for failure of CPAP treatment for bronchiolitis (P<0.05). In predicting CPAP treatment failure, no improvement in P/F after 2 hours of CPAP treatment had an area under the receiver operating characteristic curve of 0.793, with a sensitivity of 70.3% and a specificity of 82.4% at a cut-off value of 203.

CONCLUSIONS

No improvement in P/F after 2 hours of CPAP treatment, PRISM III score ≥10, development of atelectasis, and comorbidity of cardiac insufficiency can be used as predictive factors for CPAP treatment failure in infants with bronchiolitis.

Continuous positive airway pressure (CPAP) for acute bronchiolitis in children

BACKGROUND

Acute bronchiolitis is one of the most frequent causes of emergency department visits and hospitalisation in children. There is no specific treatment for bronchiolitis except for supportive treatment, which includes ensuring adequate hydration and oxygen supplementation. Continuous positive airway pressure (CPAP) aims to widen the lungs' peripheral airways, enabling deflation of overdistended lungs in bronchiolitis. Increased airway pressure also prevents the collapse of poorly supported peripheral small airways during expiration. Observational studies report that CPAP is beneficial for children with acute bronchiolitis. This is an update of a review first published in 2015.

OBJECTIVES

To assess the efficacy and safety of CPAP compared to no CPAP or sham CPAP in infants and children up to three years of age with acute bronchiolitis.

SEARCH METHODS

We conducted searches of CENTRAL (2017, Issue 12), which includes the Cochrane Acute Respiratory Infections Group's Specialised Register, MEDLINE (1946 to December, 2017), Embase (1974 to December 2017), CINAHL (1981 to December 2017), and LILACS (1982 to December 2017) in January 2018.

SELECTION CRITERIA

We considered randomised controlled trials (RCTs), quasi-RCTs, cross-over RCTs, and cluster-RCTs evaluating the effect of CPAP in children with acute bronchiolitis.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed study eligibility, extracted data using a structured pro forma, analysed data, and performed meta-analyses.

MAIN RESULTS

We included three studies with a total of 122 children (62/60 in intervention/control arms) aged up to 12 months that investigated nasal CPAP compared with supportive (or "standard") therapy. We included one new trial (72 children) that contributed data to the assessment of respiratory rate and need for mechanical ventilation for this update. The included studies were single-centre trials conducted in France, the UK, and India. Two studies were parallel-group RCTs and one was a cross-over RCT. The evidence provided by the included studies was low quality; we assessed high risk of bias for blinding, incomplete outcome data, and selective reporting, and confidence intervals were wide.The effect of CPAP on the need for mechanical ventilation in children with acute bronchiolitis was uncertain due to imprecision around the effect estimate (3 RCTs, 122 children; risk ratio (RR) 0.69, 95% confidence interval (CI) 0.14 to 3.36; low-quality evidence). None of the trials measured time to recovery. Limited, low-quality evidence indicated that CPAP decreased respiratory rate (2 RCTs, 91 children; mean difference (MD) -3.81, 95% CI -5.78 to -1.84). Only one trial measured change in arterial oxygen saturation, and the results were imprecise (19 children; MD -1.70%, 95% CI -3.76 to 0.36). The effect of CPAP on change in arterial partial carbon dioxide pressure (pCO₂) was imprecise (2 RCTs, 50 children; MD -2.62 mmHg, 95% CI -5.29 to 0.05; low-quality evidence). Duration of hospital stay was similar in both CPAP and supportive care groups (2 RCTs, 50 children; MD 0.07 days, 95% CI -0.36 to 0.50; low-quality evidence). Two studies did not report about pneumothorax, but pneumothorax did not occur in one study. No studies reported occurrences of deaths. Several outcomes (change in partial oxygen pressure, hospital admission rate (from emergency department to hospital), duration of emergency department stay, and need for intensive care unit admission) were not reported in the included studies.

AUTHORS' CONCLUSIONS

Limited, low-quality evidence suggests that breathing improved (a decreased respiratory rate) in children with bronchiolitis who received CPAP; this finding is unchanged from the 2015 review. Further evidence for this outcome was provided by the inclusion of a low-quality study for the 2018 update. Due to the limited available evidence, the effect of CPAP in children with acute bronchiolitis is uncertain for other outcomes. Larger, adequately powered trials are needed to evaluate the effect of CPAP for children with acute bronchiolitis.

High flow nasal cannula (HFNC) versus nasal continuous positive airway pressure (nCPAP) for the initial respiratory management of acute viral bronchiolitis in young infants: a multicenter randomized controlled trial (TRAMONTANE study)

PURPOSE

Nasal continuous positive airway pressure (nCPAP) is currently the gold standard for respiratory support for moderate to severe acute viral bronchiolitis (AVB). Although oxygen delivery via high flow nasal cannula (HFNC) is increasingly used, evidence of its efficacy and safety is lacking in infants.

METHODS

A randomized controlled trial was performed in five pediatric intensive care units (PICUs) to compare 7 cmH₂O nCPAP with 2 L/kg/min oxygen therapy administered with HFNC in infants up to 6 months old with moderate to severe AVB. The primary endpoint was the percentage of failure within 24 h of randomization using prespecified criteria. To satisfy noninferiority, the failure rate of HFNC had to lie within 15% of the failure rate of nCPAP. Secondary outcomes included success rate after crossover, intubation rate, length of stay, and serious adverse events.

RESULTS

From November 2014 to March 2015, 142 infants were included and equally distributed into groups. The risk difference of -19% (95% CI -35 to -3%) did not allow the conclusion of HFNC noninferiority (p = 0.707). Superiority analysis suggested a relative risk of success 1.63 (95% CI 1.02-2.63) higher with nCPAP. The success rate with the alternative respiratory support, intubation rate, durations of noninvasive and invasive ventilation, skin lesions, and length of PICU stay were comparable between groups. No patient had air leak syndrome or died.

CONCLUSION

In young infants with moderate to severe AVB, initial management with HFNC did not have a failure rate similar to that of nCPAP. This clinical trial was recorded in the National Library of Medicine registry (NCT 02457013).

Non-invasive respiratory support for infants with bronchiolitis: a national survey of practice

Background

Bronchiolitis is a common respiratory illness of early childhood. For most children it is a mild self-limiting disease but a small number of children develop respiratory failure. Nasal continuous positive airway pressure (nCPAP) has traditionally been used to provide non-invasive respiratory support in these children, but there is little clinical trial evidence to support its use. More recently, high-flow nasal cannula therapy (HFNC) has emerged as a novel respiratory support modality. Our study aims to describe current national practice and clinician preferences relating to use of non-invasive respiratory support (nCPAP and HFNC) in the management of infants (<12 months old) with acute bronchiolitis.

Methods

We performed a cross-sectional web-based survey of hospitals with inpatient paediatric facilities in England and Wales. Responses were elicited from one senior doctor and one senior nurse at each hospital. We analysed the proportion of hospitals using HFNC and nCPAP; clinical thresholds for their initiation; and clinician preferences regarding first-line support modality and future research.

Results

The survey was distributed to 117 of 171 eligible hospitals; 97 hospitals provided responses (response rate: 83%). The majority of hospitals were able to provide nCPAP (89/97, 91.7%) or HFNC (71/97, 73.2%); both were available at 65 hospitals (67%). nCPAP was more likely to be delivered in a ward setting in a general hospital, and in a high dependency setting in a tertiary centre. There were differences in the oxygenation and acidosis thresholds, and clinical triggers such as recurrent apnoeas or work of breathing that influenced clinical decisions, regarding when to start nCPAP or HFNC. More individual respondents with access to both modalities (74/106, 69.8%) would choose HFNC over nCPAP as their first-line treatment option in a deteriorating child with bronchiolitis.

Conclusions

Despite lack of randomised trial evidence, nCPAP and HFNC are commonly used in British hospitals to support infants with acute bronchiolitis. HFNC appears to be currently the preferred first-line modality for non-invasive respiratory support due to perceived ease of use.

Electronic supplementary material

The online version of this article (doi:10.1186/s12887-017-0785-0) contains supplementary material, which is available to authorized users.

Effectiveness of flow inflating device in providing Continuous Positive Airway Pressure for critically ill children in limited-resource settings: A prospective observational study

Background and Aims:

Noninvasive ventilation (NIV) is an emerging popular concept, which includes bi-level positive airway pressure or continuous positive airway pressure (CPAP). In settings with scarce resources for NIV machines, CPAP can be provided through various indigenous means and one such mode is flow inflating device - Jackson-Rees circuit (JR)/Bain circuit. The study analyses the epidemiology, various clinical indications, predictors of CPAP failure, and stresses the usefulness of flow inflating device as an indigenous way of providing CPAP.

Methods:

A prospective observational study was undertaken in the critical care unit of a Government Tertiary Care Hospital, from November 2013 to September 2014. All children who required CPAP in the age group 1 month to 12 years of both sexes were included in this study. They were started on indigenous CPAP through flow inflating device on clinical grounds based on the pediatric assessment triangle, and the duration and outcome were analyzed.

Results:

This study population included 214 children. CPAP through flow inflating device was successful in 89.7% of cases, of which bronchiolitis accounted for 98.3%. A prolonged duration of CPAP support of >96 h was required in pneumonia. CPAP failure was noted in 10.3% of cases, the major risk factors being children <1 year and pneumonia with septic shock.

Conclusion:

We conclude that flow inflating devices - JR/Bain circuit are effective as an indigenous CPAP in limited resource settings. Despite its benefits, CPAP is not a substitute for invasive ventilation, as when the need for intubation arises timely intervention is needed.

Use of Nasal Bubble CPAP in Children with Hypoxemic Clinical Pneumonia-Report from a Resource Limited Set-Up

OBJECTIVE

Nasal bubble continuous positive airway pressure (bCPAP) is preferred in developing economies for easy applicability and low cost. Because its use in older children is unexplored, we sought to evaluate its utility in hypoxemic clinical pneumonia.

METHODS

Of 330 children (1 month-12 years) with clinical pneumonia enrolled prospectively over 1 year, those with increased work of breathing and/or SpO2 <92% received bCPAP delivered via an underwater 'T' tube through nasal prongs. Proportion requiring intubation despite bCPAP constituted primary outcome. Incidence of complications, duration of bCPAP and emergency stay were secondary outcomes.

RESULTS

Oxygen was initiated by nasal prongs (NPO2) in 204 (61.8%), and by bCPAP in 110 (33.3%). Sixteen (4.8%) were intubated at the outset. Fifty-three (25.9%) on NPO2 were shifted to bCPAP for worsening distress and hypoxemia. Only three (1.8%) from bCPAP group required intubation, of which one died. Failure rate and complications were negligent. The median emergency stay was 4 days.

CONCLUSIONS

Nasal bCPAP was safe and effective in children with hypoxemic clinical pneumonia.

Efficacy of noninvasive mechanical ventilation in prevention of intubation and reintubation in the pediatric intensive care unit

PURPOSE

To determine the efficiency of noninvasive mechanical ventilation (NIV) both in protection from intubation and in preventing reintubation of postextubation in patients in the pediatric intensive care unit (PICU).

METHODS

A prospective observational study was conducted in a multidisciplinary 10-bed tertiary PICU of a university hospital. All patients were admitted to our unit from June 2012 to May 2014 and deemed to be candidates to receive continuous positive airway pressure or bilevel positive airway pressure.

MEASUREMENTS AND RESULTS

We performed 160 NIV episodes in 137 patients. Their median age was 9 months (range, 1-240 months), and their median weight was 7.5 kg (range, 2.5-65 kg). Fifty-seven percent of patients were male. Noninvasive mechanical ventilation was successful in 70% (112 episodes) of patients. There was an underlying illness in 83.8% (134 episodes) of the patients. Bilevel positive airway pressure support was given to 57.5% (92 episodes) of the patients, whereas the remaining 42.5% (68 episodes) received continuous positive airway pressure support. Among the causes of respiratory failure in our patients, the most frequent were postextubation, pneumonia, bronchiolitis, atelectasia, and cardiogenic pulmonary edema. Sedation was applied in 43.1% of the episodes. Complications were detected in 29 episodes (18.1 %). The NIV failure group showed higher Pediatric Risk of Mortality III-24 score, shorter NIV duration, more frequent underlying disease, lower number fed, longer length of PICU stay, and hospital stay, and mortality was higher.

CONCLUSIONS

Noninvasive mechanical ventilation effectively and reliably reduced endotracheal intubation in the treatment of respiratory failure due to different clinical situations. Our results suggest that NIV can play an important role in PICUs in helping to avoid intubation and prevent reintubation. Although there were serious underlying diseases in most of our patients, such as immunosuppression, 70% avoided intubation with use of NIV.

CPAP and High-Flow Nasal Cannula Oxygen in Bronchiolitis

Severe respiratory failure develops in some infants with bronchiolitis because of a complex pathophysiologic process involving increased airways resistance, alveolar atelectasis, muscle fatigue, and hypoxemia due to mismatch between ventilation and perfusion. Nasal CPAP and high-flow nasal cannula (HFNC) oxygen may improve the work of breathing and oxygenation. Although the mechanisms behind these noninvasive modalities of respiratory support are not well understood, they may help infants by way of distending pressure and delivery of high concentrations of warmed and humidified oxygen. Observational studies of varying quality have suggested that CPAP and HFNC may confer direct physiologic benefits to infants with bronchiolitis and that their use has reduced the need for intubation. No trials to our knowledge, however, have compared CPAP with HFNC in bronchiolitis. Two randomized trials compared CPAP with oxygen delivered by low-flow nasal cannula or face mask and found some improvements in blood gas results and some physiologic parameters, but these trials were unable to demonstrate a reduction in the need for intubation. Two trials evaluated HFNC in bronchiolitis (one comparing it with headbox oxygen, the other with nebulized hypertonic saline), with the results not seeming to suggest important clinical or physiologic benefits. In this article, we review the pathophysiology of respiratory failure in bronchiolitis, discuss these trials in detail, and consider how future research studies may be designed to best evaluate CPAP and HFNC in bronchiolitis.

Noninvasive ventilation in acute respiratory failure from respiratory syncytial virus bronchiolitis

Objectives

The present study focused on respiratory syncytial virus bronchiolitis with respiratory failure. The aim of the study was to determine whether noninvasive ventilation reduces the need for endotracheal intubation or slows the clinical progression of acute respiratory syncytial virus bronchiolitis by reducing the incidence of infectious complications.

Methods

The present study was a retrospective cohort study. Cohort A was comprised of children who were admitted to the pediatric intensive and special care unit from 2003-2005 before starting noninvasive ventilation; cohort B was comprised of children who were admitted to the pediatric intensive and special care unit from 2006-2008 after starting noninvasive ventilation. With the exception of noninvasive ventilation, the therapeutic support was the same for the two groups. All children who were diagnosed with respiratory syncytial virus bronchiolitis and respiratory failure between November 2003 and March 2008 were included in the cohort. Demographic, clinical and blood gas variables were analyzed.

Results

A total of 162 children were included; 75% of the subjects were less than 3 months old. Group A included 64 children, and group B included 98 children. In group B, 34 of the children required noninvasive ventilation. The distributions of the variables age, preterm birth, congenital heart disease, cerebral palsy and chronic lung disease were similar between the two groups. On admission, the data for blood gas analysis and the number of apneas were not significantly different between the groups. In group B, fewer children required invasive ventilation (group A: 12/64 versus group B: 7/98; p=0.02), and there was a reduction in the number of cases of bacterial pneumonia (group A: 19/64 versus group B: 12/98; p=0.008). There was no record of mortality in either of the groups.

Conclusion

By comparing children with the same disease both before and after noninvasive ventilation was used for ventilation support, we verified a reduction in infectious complications and cases requiring intubation.

Variability of intensive care management for children with bronchiolitis

OBJECTIVE

To determine the extent of variability in testing and treatment of children with bronchiolitis requiring intensive care.

METHODS

This prospective, multicenter observational study included 16 academic children's hospitals across the United States during the 2007 to 2010 fall and winter seasons. The study included children<2 years old hospitalized with bronchiolitis who required admission to the ICU and/or continuous positive airway pressure (CPAP) within 24 hours of admission. Among the 2207 enrolled patients with bronchiolitis, 342 children met inclusion criteria. Clinical data and nasopharyngeal aspirates were collected.

RESULTS

Respiratory distress severity scores and intraclass correlation coefficients were calculated. The study patients' median age was 2.6 months, and 59% were male. Across the 16 sites, the median respiratory distress severity score was 5.1 (interquartile range: 4.5-5.4; P<.001). The median value of the percentages for all sites using CPAP was 15% (range: 3%-100%), intubation was 26% (range: 0%-100%), and high-flow nasal cannula (HFNC) was 24% (range: 0%-94%). Adjusting for site-specific random effects (as well as children's demographic characteristics and severity of bronchiolitis), the intraclass correlation coefficient for CPAP and/or intubation was 21% (95% confidence interval: 8-44); for HFNC, it was 44.7% (95% confidence interval: 24-67).

CONCLUSIONS

In this multicenter study of children requiring intensive care for bronchiolitis, we identified substantial institutional variability in testing and treatment, including use of CPAP, intubation, and HFNC. These differences were not explained by between-site differences in patient characteristics, including severity of illness. Further research is needed to identify best practices for intensive care interventions for this major cause of pediatric hospitalization.

Continuous positive airway pressure (CPAP) for acute bronchiolitis in children

BACKGROUND

Acute bronchiolitis is one of the most frequent causes of emergency department visits and hospitalisation in infants. There is no specific treatment for bronchiolitis except for supportive therapy. Continuous positive airway pressure (CPAP) is supposed to widen the peripheral airways of the lung, allowing deflation of over-distended lungs in bronchiolitis. The increase in airway pressure also prevents the collapse of poorly supported peripheral small airways during expiration. In observational studies, CPAP is found to be beneficial in acute bronchiolitis.

OBJECTIVES

To assess the efficacy and safety of CPAP compared to no CPAP or sham CPAP in infants and children up to three years of age with acute bronchiolitis.

SEARCH METHODS

We searched CENTRAL (2014, Issue 3), MEDLINE (1946 to April week 2, 2014), EMBASE (1974 to April 2014), CINAHL (1981 to April 2014) and LILACS (1982 to April 2014).

SELECTION CRITERIA

We considered randomised controlled trials (RCTs), quasi-RCTS, cross-over RCTs and cluster-RCTs evaluating the effect of CPAP in children with acute bronchiolitis.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed study eligibility, extracted data using a structured proforma, analysed the data and performed meta-analyses.

MAIN RESULTS

We included two studies with a total of 50 participants under 12 months of age. In one study there was a high risk of bias for incomplete outcome data and selective reporting, and both studies had an unclear risk of bias for several domains including random sequence generation. The effect of CPAP on the need for mechanical ventilation in children with acute bronchiolitis was uncertain due to imprecision around the effect estimate (two RCTs, 50 participants; risk ratio (RR) 0.19, 95% CI 0.01 to 3.63; low quality evidence). Neither trial measured our other primary outcome of time to recovery. One trial found that CPAP significantly improved respiratory rate compared with no CPAP (one RCT, 19 participants; mean difference (MD) -5.70 breaths per minute, 95% CI -9.30 to -2.10), although the other study reported no difference between groups with no numerical data to pool. Change in arterial oxygen saturation was measured in only one trial and the results were imprecise (one RCT, 19 participants; MD -1.70%, 95% CI -3.76 to 0.36). The effect of CPAP on the change in partial pressure of carbon dioxide (pCO2) was also imprecise (two RCTs, 50 participants; MD -2.62 mmHg, 95% CI -5.29 to 0.05; low quality evidence). Duration of hospital stay was similar in both of the groups (two RCTs, 50 participants; MD 0.07 days, 95% CI -0.36 to 0.50; low quality evidence). Both trials reported no cases of pneumothorax and there were no deaths in either study. Change in partial pressure of oxygen (pO2), hospital admission rate (from emergency department to hospital), duration of emergency department stay, need for intensive care unit admission, local nasal effects and shock were not measured in either study.

AUTHORS' CONCLUSIONS

The effect of CPAP in children with acute bronchiolitis is uncertain due to the limited evidence available. Larger trials with adequate power are needed to evaluate the effect of CPAP in children with acute bronchiolitis.

Bronchiolitis

Everyone on the planet is exposed to respiratory syncytial virus (RSV) infection by the age of 2 years. Most infants admitted to the pediatric intensive care unit (PICU) for respiratory support during this infection are previously healthy, but their principal risk for needing PICU treatment is young age. That is, if you are born in October/November in the northern hemisphere, then your first winter exposure to RSV is likely to be when you are less than 4 months of age and vulnerable because of poor respiratory mechanical reserve (Alonso et al. 2007). However, if you are born in May/June, then you will be 7–8 months during your first winter exposure to RSV, much bigger and stronger and have more efficient thoracic and diaphragmatic mechanics. In the PICU, the main predictors of severe outcome in previously well infants appear to be young age, presence of apnea, and pulmonary consolidation on admission chest radiograph (Tasker et al. 2000; Lopez Guinea et al. 2007). Taken together, we can say that more severe RSV bronchiolitis in PICU practice is typically a problem of pulmonary consolidation, poor respiratory mechanics, and poor reserve, in the younger infant.

Noninvasive ventilation in pediatric emergency care: a literature review and description of our experience

Noninvasive ventilation (NIV) refers to a kind of mechanical respiratory support used in order to avoid the progression of respiratory failure to endotracheal intubation. Even though if this method is widely known in patients affected by chronic diseases and in children admitted in pediatric and neonatal intensive care units, few data are actually available on its use in intermediate care units. The present review focuses on the efficiency of NIV performed in children with acute respiratory failure due to different conditions. Moreover, the authors have described their experience with NIV in pediatric patients admitted to their acute and emergency room where NIV was started, well tolerated and led to an improvement of gas exchanges, decreasing the muscular respiratory work and endotracheal intubation avoidance in most of the patients.

Initiation de la ventilation non invasive aux urgences pédiatriques dans les bronchiolites sévères du nourrisson

Introduction

La ventilation non invasive (VNI) dans les bronchiolites sévères du nourrisson s’est développée rapidement en réanimation et au service mobile d’urgence et réanimation pédiatrique (Smur) depuis 2003. Les objectifs de cette étude sont de vérifier les indications de mise sous VNI utilisées aux urgences pédiatriques d’Ambroise-Paré en les comparant à celles utilisées en réanimation et de confirmer l’efficacité de cette technique aux urgences pédiatriques.

Méthodes et population

Étude rétrospective sur 31 nourrissons ventilés par VNI pour bronchiolite sévère aux urgences pédiatriques de l’hôpital Ambroise-Paré (92) des hivers 2009 à 2011.

Résultats

La population étudiée était composée de 16 % d’anciens prématurés sans hypotrophie ni antécédent notable et âgés d’en moyenne deux mois au moment de la bronchiolite. Le pourcentage de bronchiolites apnéisantes (seule indication de VNI selon la conférence de consensus de 2006) était de 17 %. Au moins deux indications de recours à la VNI ont été retrouvées pour chaque patient. Cinquante-huit pour cent des nourrissons étaient transférés plus de deux heures après la mise sous VNI, avec une amélioration constatée sur la fréquence respiratoire (FR), la saturation, la PCO₂ et le pH (p < 0,001) et sans complications aux urgences. La VNI a été poursuivie en réanimation dans 84 % des cas. La durée moyenne de VNI était de 2,7 jours, celle d’hospitalisation en réanimation de 4,2 jours.

Conclusion

L’utilisation de la VNI aux urgences pédiatriques est une procédure simple, permettant une prise en charge précoce, avant transfert en réanimation, des bronchiolites sévères du nourrisson et permettant une amélioration clinique et gazométrique de leur insuffisance respiratoire.

Comparison of a high-flow humidified nasal cannula to nasal continuous positive airway pressure in children with acute bronchiolitis: experience in a pediatric intensive care unit

The objective of the current study is to compare the use of a nasal continuous positive airway pressure (nCPAP) to a high-flow humidified nasal cannula (HFNC) in infants with acute bronchiolitis, who were admitted to a pediatric intensive care unit (PICU) during two consecutive seasons. We retrospectively reviewed the medical records of all infants admitted to a PICU at a tertiary care French hospital during the bronchiolitis seasons of 2010/11 and 2011/12. Infants admitted to the PICU, who required noninvasive respiratory support, were included. The first noninvasive respiratory support modality was nCPAP during the 2010/11 season, while HFNC was used during the 2011/2012 season. We compared the length of stay (LOS) in the PICU; the daily measure of PCO2 and pH; and the mean of the five higher values of heart rate (HR), respiratory rate (RR), FiO2, and SpO2 each day, during the first 5 days. Thirty-four children met the inclusion criteria: 19 during the first period (nCPAP group) and 15 during the second period (HFNC group). Parameters such as LOS in PICU and oxygenation were similar in the two groups. Oxygen weaning occurred during the same time for the two groups. There were no differences between the two groups for RR, HR, FiO2, and CO2 evolution. HFNC therapy failed in three patients, two of whom required invasive mechanical ventilation, versus one in the nCPAP group.

CONCLUSION

We did not find a difference between HFNC and nCPAP in the management of severe bronchiolitis in our PICU. Larger prospective studies are required to confirm these findings.

Continuous positive airway pressure for bronchiolitis in a general paediatric ward; a feasibility study

Background

Continuous positive airway pressure (CPAP) is commonly used to relieve respiratory distress in infants with bronchiolitis, but has mostly been studied in an intensive care setting. Our prime aim was to evaluate the feasibility of CPAP for infants with bronchiolitis in a general paediatric ward, and secondary to assess capillary PCO₂ (cPCO₂) levels before and during treatment.

Methods

From May 1^st 2008 to April 30^th 2012, infants with bronchiolitis at Stavanger University Hospital were treated with CPAP in a general paediatric ward, but could be referred to an intensive care unit (ICU) when needed, according to in-house guidelines. Levels of cPCO₂ were prospectively registered before the start of CPAP and at approximately 4, 12, 24 and 48 hours of treatment as long as CPAP was given. We had a continuous updating program for the nurses and physicians caring for the infants with CPAP. The study was population based.

Results

672 infants (3.4%) were hospitalized with bronchiolitis. CPAP was initiated in 53 infants (0.3%; 7.9% of infants with bronchiolitis), and was well tolerated in all but three infants. 46 infants were included in the study, the majority of these (n = 33) were treated in the general ward only. These infants had lower cPCO₂ before treatment (8.0; 7.7, 8.6)(median; quartiles) than those treated at the ICU (n = 13) (9.3;8.5, 9.9) (p < 0.001). The level of cPCO₂ was significantly reduced after 4 h in both groups; 1.1 kPa (paediatric ward) (p < 0.001) and 1.3 kPa (ICU) (p = 0.002). Two infants on the ICU did not respond to CPAP (increasing cPCO₂ and severe apnoe) and were given mechanical ventilation, otherwise no side effects were observed in either group treated with CPAP.

Conclusion

Treatment with CPAP for infants with bronchiolitis may be feasible in a general paediatric ward, providing sufficient staffing and training, and the possibility of referral to an ICU when needed.

Acute bronchiolitis in infants, a review

Acute viral bronchiolitis is one of the most common medical emergency situations in infancy, and physicians caring for acutely ill children will regularly be faced with this condition. In this article we present a summary of the epidemiology, pathophysiology and diagnosis, and focus on guidelines for the treatment of bronchiolitis in infants. The cornerstones of the management of viral bronchiolitis are the administration of oxygen and appropriate fluid therapy, and overall a “minimal handling approach” is recommended. Inhaled adrenaline is commonly used in some countries, but the evidences are sparse. Recently, inhalation with hypertonic saline has been suggested as an optional treatment. When medical treatment fails to stabilize the infants, non-invasive and invasive ventilation may be necessary to prevent and support respiratory failure. It is important that relevant treatment algorithms exist, applicable to all levels of the treatment chain and reflecting local considerations and circumstances.

Infants with severe respiratory syncytial virus needed less ventilator time with nasal continuous airways pressure then invasive mechanical ventilation

AIM

Nasal continuous positive airway pressure (NCPAP) has been proposed as an early first-line support for infants with severe respiratory syncytial virus (RSV) infection. We hypothesised that infants <6 months with severe RSV would require shorter ventilator support on NCPAP than invasive mechanical ventilation (IMV).

METHODS

Retrospective cohort analysis of infants admitted to two paediatric intensive care units, one primarily using NCPAP and one exclusively using IMV, between January 2008 and February 2010.

RESULTS

We studied 133 (NCPAP n = 89, IMV n = 46) consecutively admitted infants. On admission, disease severity [i.e. Paediatric RISk of Mortality (PRISM) II score (NCPAP 5.1 ± 2.8 vs. IMV 12.2 ± 6.0, p < 0.001) and SpO2 /Fi O2 ratio (NCPAP 309 ± 81 vs. IMV 135 ± 98, p < 0.001)] was higher in the IMV group. NCPAP remained independently associated with shorter ventilatory support (hazard ratio 2.3, 95% CI 1.1-4.7, p = 0.022) after adjusting for PRISM II score, PCO2 , SpO2 /Fi O2 ratio, bronchopulmonary dysplasia and occurrence of clinically suspected secondary bacterial pneumonia.

CONCLUSION

Nasal continuous positive airway pressure was independently associated with a shorter duration of ventilatory support. Differences in baseline disease severity mandate a randomised trial before the routine use of NCPAP can be recommended.

Improved clinical and economic outcomes in severe bronchiolitis with pre-emptive nCPAP ventilatory strategy

PURPOSE

Severe bronchiolitis is the leading cause of admission to the pediatric intensive care unit (PICU). Nasal continuous positive airway pressure (nCPAP) has become the primary respiratory support, replacing invasive mechanical ventilation (MV). Our objective was to evaluate the economic and clinical consequences following implementation of this respiratory strategy in our unit.

METHODS

This was a retrospective cohort analysis of 525 infants with bronchiolitis requiring respiratory support and successively treated during two distinct periods with invasive MV between 1996 and 2000, P1 (n = 193) and nCPAP between 2006 and 2010, P2 (n = 332). Costs were estimated using the hospital cost billing reports.

RESULTS

Patients' baseline characteristics were similar between the two periods. P2 is associated with a significant decrease in the length of ventilation (LOV) (4.1 ± 3.5 versus 6.9 ± 4.6 days, p < 0.001), PICU length of stay (LOS) (6.2 ± 4.6 versus 9.7 ± 5.5 days, p < 0.001) and hospital LOS. nCPAP was independently associated with a shorter duration of ventilatory support than MV (hazard ratio 1.8, 95% CI 1.5-2.2, p < 0.001). nCPAP was also associated with a significant decrease in ventilation-associated complications, and less invasive management. The mean cost of acute viral bronchiolitis-related PICU hospitalizations was significantly decreased, from 17,451 to 11,205 € (p < 0.001). Implementation of nCPAP led to a reduction of the total annual cost of acute viral bronchiolitis hospitalizations of 715,000 €.

CONCLUSION

nCPAP in severe bronchiolitis is associated with a significant improvement in patient management as shown by the reduction in invasive care, LOV, PICU LOS, hospital LOS, and economic burden.

Pathophysiology of Acute Respiratory Failure in Children with Bronchiolitis and Effect of CPAP

Acute bronchiolitis is the most common lower respiratory tract infection (LRTI) during the first year of life. Respiratory syncytial virus (RSV) infection is the most prevalent virus found in these children, accounting for 60–80 % of cases. The rate of hospitalization is less than 2 %. Up to 8 % of those hospitalized require ventilatory support [1, 2].

Efficacy and predictors of success of noninvasive ventilation for prevention of extubation failure in critically ill children with heart disease

The study aimed primarily to evaluate the efficacy of noninvasive ventilation (NIV) and to identify possible predictors for success of NIV therapy in preventing extubation failure in critically ill children with heart disease. The secondary objectives of this study were to assess the efficacy of prophylactic NIV therapy initiated immediately after tracheal extubation and to determine the characteristics, outcomes, and complications associated with NIV therapy in pediatric cardiac patients. A retrospective review examined the medical records of all children between the ages 1 day and 18 years who sustained acute respiratory failure (ARF) that required NIV in the cardiovascular intensive care unit (CVICU) at Lucile Packard Children's Hospital between January 2008 and June 2010. Patients were assigned to a prophylactic group if NIV was started directly after extubation and to a nonprophylactic group if NIV was started after signs and symptoms of ARF developed. Patients were designated as responders if they received NIV and did not require reintubation during their CVICU stay and nonresponders if they failed NIV and reintubation was performed. The data collected included demographic data, preexisting conditions, pre-event characteristics, event characteristics, and outcome data. The outcome data evaluated included success or failure of NIV, duration of NIV, CVICU length of stay (LOS), hospital LOS, and hospital mortality. The two complications of NIV assessed in the study included nasal bridge or forehead skin necrosis and pneumothorax. The 221 eligible events during the study period involved 172 responders (77.8 %) and 49 nonresponders (22.2 %). A total of 201 events experienced by the study cohort received continuous positive airway pressure (CPAP), with 156 responders (78 %), whereas 20 events received bilevel positive airway pressure (BiPAP), with 16 responders (80 %). In the study, 58 events (26.3 %) were assigned to the prophylactic group and 163 events (73.7 %) to the nonprophylactic group. Compared with the nonprophylactic group, the prophylactic group experienced significantly shorter CVICU LOS (median, 49 vs 88 days; p = 0.03) and hospital LOS (median, 60 vs 103 days; p = 0.05). The CVICU LOS and hospital LOS did not differ significantly between the responders (p = 0.56) and nonresponders (p = 0.88). Significant variables identifying a responder included a lower risk-adjusted classification for congenital heart surgery (RACHS-1) score (1-3), a good left ventricular ejection fraction, a normal respiratory rate (RR), normal or appropriate oxygen saturation, prophylactic or therapeutic glucocorticoid therapy within 24 h of NIV initiation, presence of atelectasis, fewer than two organ system dysfunctions, fewer days of intubation before extubation, no clinical or microbiologic evidence of sepsis, and no history of reactive airway disease. As a well-tolerated therapy, NIV can be safely and successfully applied in critically ill children with cardiac disease to prevent extubation failure. The independent predictors of NIV success include lower RACHS-1 classification, presence of atelectasis, steroid therapy received within 24 h after NIV, and normal heart rate and oxygen saturations demonstrated within 24 h after initiation of NIV.

6 cmH2O continuous positive airway pressure versus conventional oxygen therapy in severe viral bronchiolitis: a randomized trial

OBJECTIVE

To compare the effects of nasal continuous positive airway pressure (nCPAP) and conventional oxygen therapy on the clinical signs of respiratory distress and the respiratory muscle workload in acute viral bronchiolitis.

DESIGN

Prospective, randomized, monocentric study carried out in the pediatric intensive care unit (PICU) of a university hospital.

PATIENTS

Infants <6 months old, admitted to the PICU with severe respiratory syncytial virus bronchiolitis.

INTERVENTION

The patients were randomized into two groups for 6 hr. The nCPAP group (n = 10) received 6 cmH(2)O pressure support delivered by a jet flow generator and the control group (n = 9) received an air/oxygen mixture from a heated humidifier. Respiratory distress was assessed by the modified Wood's clinical asthma score (m-WCAS), and inspiratory muscle work was evaluated by calculating the pressure-time product per breath (PTP(insp) /breath) and per minute (PTP(insp) /min) from the esophageal pressure (Pes) recordings.

MEASUREMENTS AND MAIN RESULTS

Compared with control condition, nCPAP decreased m-WCAS [-2.4 (1.05) vs. -0.5 (1.3), P = 0.03], PTPes(insp)/breath [-9.7 (5.7) vs. -1.4 (8.2), P = 0.04], PTPes(insp) /min [-666 (402) vs. -116 (352), P = 0.015], and FiO(2) [-7 (10) vs. +5 (15), P = 0.05]. Significant worsening of m-WCAS was only observed in the control group (4/9 vs. 0/10, P = 0.03).

CONCLUSIONS

nCPAP rapidly decreased inspiratory work in young infants with acute bronchiolitis. Improvement in the respiratory distress score at 6 hr was proportional to the initial clinical severity, suggesting the importance of rapid nCPAP initiation in the more severe forms of the disease.

Use of continuous positive airway pressure during stabilisation and retrieval of infants with suspected bronchiolitis

AIM

Infants with viral bronchiolitis are often hospitalised with a proportion requiring respiratory support. The aim of this review was to examine the use of nasal prong continuous positive airway pressure (CPAP) as a management strategy for infants with a diagnosis of bronchiolitis, who required stabilisation and transport to a tertiary centre.

METHOD

A retrospective audit of infants with bronchiolitis requiring CPAP during transport between January 2003 and June 2007.

RESULTS

Nasal CPAP was initiated in 54 infants with 51 of these (34 ex-preterm, 17 term) subsequently continuing on CPAP during retrieval. Mean CPAP pressure was 7 cmH(2)O. Oxygenation improved between stabilisation and the end of retrieval (P < 0.01). During retrieval, there was no significant increase in transcutaneous CO(2), no infant required endotracheal ventilation and no adverse events were noted. Five infants were intubated within the first 24 h of admission at the receiving hospital.

CONCLUSION

This review demonstrated that use of nasal prong CPAP to transport infants with bronchiolitis was a safe management strategy in those with moderate to severe disease severity.

Absence of inspiratory laryngeal constrictor muscle activity during nasal neurally adjusted ventilatory assist in newborn lambs

In nonsedated newborn lambs, nasal pressure support ventilation (nPSV) can lead to an active glottal closure in early inspiration, which can limit lung ventilation and divert air into the digestive system, with potentially deleterious consequences. During volume control ventilation (nVC), glottal closure is delayed to the end of inspiration, suggesting that it is reflexly linked to the maximum value of inspiratory pressure. Accordingly, the aim of the present study was to test whether inspiratory glottal closure develops at the end of inspiration during nasal neurally adjusted ventilatory assist (nNAVA), an increasingly used ventilatory mode where maximal pressure is also reached at the end of inspiration. Polysomnographic recordings were performed in eight nonsedated, chronically instrumented lambs, which were ventilated with progressively increasing levels of nPSV and nNAVA in random order. States of alertness, diaphragm, and glottal muscle electrical activity, tracheal pressure, Spo(2), tracheal Pet(CO(2)), and respiratory inductive plethysmography were continuously recorded. Although phasic inspiratory glottal constrictor electrical activity appeared during nPSV in 5 of 8 lambs, it was never observed at any nNAVA level in any lamb, even at maximal achievable nNAVA levels. In addition, a decrease in Pco(2) was neither necessary nor sufficient for the development of inspiratory glottal constrictor activity. In conclusion, nNAVA does not induce active inspiratory glottal closure, in contrast to nPSV and nVC. We hypothesize that this absence of inspiratory activity is related to the more physiological airway pressurization during nNAVA, which tightly follows diaphragm electrical activity throughout inspiration.

Non-invasive ventilation in acute respiratory failure in children

The aim of this paper is to assess the clinical efficacy of non-invasive ventilation (NIV) in avoiding endotracheal intubation (ETI), to demonstrate clinical and gasometric improvement and to identify predictive risk factors associated with NIV failure. An observational prospective clinical study was carried out. Included Patients with acute respiratory disease (ARD) treated with NIV, from November 2006 to January 2010 in a Pediatric Intensive Care Unit (PICU). NIV was used in 151 patients with acute respiratory failure (ARF). Patients were divided in two groups: NIV success and NIV failure, if ETI was required. Mean age was 7.2±20.3 months (median: 1 min: 0,3 max.: 156). Main diagnoses were bronchiolitis in 102 (67.5%), and pneumonia in 44 (29%) patients. There was a significant improvement in respiratory rate (RR), heart rate (HR), pH, and pCO(2) at 2, 6, 12 and 24 hours after NIV onset (P<0.05) in both groups. Improvement in pulse oximetric saturation/fraction of inspired oxygen (SpO(2)/FiO(2)) was verified at 2, 4, 6, 12 and 24 hours after NIV onset in the success group (P<0.001). In the failure group, significant SpO(2)/FiO(2) improvement was only observed in the first 4 hours. NIV failure occurred in 34 patients (22.5%). Risk factors for NIV failure were apnea, prematurity, pneumonia, and bacterial co-infection (P<0.05). Independent risk factors for NIV failure were apneia (P<0.001; odds ratio 15.8; 95% confidence interval: 3.42-71.4) and pneumonia (P<0.001, odds ratio 31.25; 95% confidence interval: 8.33-111.11). There were no major complications related with NIV. In conclusion this study demonstrates the efficacy of NIV as a form of respiratory support for children and infants with ARF, preventing clinical deterioration and avoiding ETI in most of the patients. Risk factors for failure were related with immaturity and severe infection.

Use of continuous positive airway pressure (CPAP) in acute viral bronchiolitis: a systematic review

INTRODUCTION

Continuous positive airway pressure (CPAP), used either alone or associated with heliox (CPAP-He), has become a popular therapeutic option for bronchiolitis. This systematic review assesses the impact of CPAP on endotracheal intubation, carbon dioxide pressure (PCO(2) ) and respiratory distress in patients with bronchiolitis.

METHODS

Systematic search including studies that used CPAP or CPAP-He in infants with bronchiolitis admitted to a PICU. Data analysis included descriptive statistics and the GRADE system.

RESULTS

Five CPAP (one crossover randomized controlled trial [RCT] and four before-after studies) and three CPAP-He (one quasi-RCT and two before-after) studies were included. CPAP was reported to reduce PCO(2) (-6.9 to -11.7 mmHg, respectively, P < 0.015), respiratory rate (-12 to -16 breaths/min after 2 hr, P < 0.01) and the modified Wood clinical asthma score (mWCAS, -2.2 points after 1 hr, P < 0.01). CPAP-He studies observed decreases in PCO(2) (-9.7 mmHg, P < 0.05), mWCAS (-2.12 points, P < 0.001), and respiratory rate (-8 to -13.7 breaths/min, P < 0.05) after 1 hr of treatment. Endotracheal intubation rates ranged from 0-12.5% (CPAP-He) to 17-27% (CPAP). After applying the GRADE system, the quality of evidence for a beneficial effect of CPAP and CPAP-He was classified as low.

CONCLUSIONS

The evidence supporting the use of CPAP to reduce PCO(2) and respiratory distress in bronchiolitis is of low methodological quality, and there is no conclusive evidence that CPAP reduces the need for intubation. No definitive conclusions could be drawn about the CPAP-He effect. Further research using higher quality methodology is needed to clarify the beneficial role of these interventions.

Noninvasive positive pressure ventilation for acute respiratory failure in children: a concise review

Noninvasive positive pressure ventilation (NPPV) refers to the delivery of mechanical respiratory support without the use of endotracheal intubation (ETI). The present review focused on the effectiveness of NPPV in children > 1 month of age with acute respiratory failure (ARF) due to different conditions. ARF is the most common cause of cardiac arrest in children. Therefore, prompt recognition and treatment of pediatric patients with pending respiratory failure can be lifesaving. Mechanical respiratory support is a critical intervention in many cases of ARF. In recent years, NPPV has been proposed as a valuable alternative to invasive mechanical ventilation (IMV) in this acute setting. Recent physiological studies have demonstrated beneficial effects of NPPV in children with ARF. Several pediatric clinical studies, the majority of which were noncontrolled or case series and of small size, have suggested the effectiveness of NPPV in the treatment of ARF due to acute airway (upper or lower) obstruction or certain primary parenchymal lung disease, and in specific circumstances, such as postoperative or postextubation ARF, immunocompromised patients with ARF, or as a means to facilitate extubation. NPPV was well tolerated with rare major complications and was associated with improved gas exchange, decreased work of breathing, and ETI avoidance in 22-100% of patients. High FiO₂ needs or high PaCO₂ level on admission or within the first hours after starting NPPV appeared to be the best independent predictive factors for the NPPV failure in children with ARF. However, many important issues, such as the identification of the patient, the right time for NPPV application, and the appropriate setting, are still lacking. Further randomized, controlled trials that address these issues in children with ARF are recommended.

High flow nasal cannulae therapy in infants with bronchiolitis

OBJECTIVES

To determine whether the introduction of heated humidified high-flow nasal cannulae (HFNC) therapy was associated with decreased rates of intubation for infants <24 months old with bronchiolitis admitted to a pediatric intensive care unit (PICU).

STUDY DESIGN

A retrospective chart review of infants with bronchiolitis admitted before and in the season after introduction of HFNC.

RESULTS

In the season after the introduction of HFNC, only 9% of infants admitted to the PICU with bronchiolitis required intubation, compared with 23% in the prior season (P=.043). This 68% decrease in need for intubation persisted in a logistic regression model controlling for age, weight, and RSV status. HFNC therapy resulted in a greater decrease in respiratory rate compared with other forms of respiratory support, and those infants with the greatest decrease in respiratory rate were least likely to be intubated. In addition, median PICU length of stay for children with bronchiolitis decreased from 6 to 4 days after the introduction of HFNC.

DISCUSSION

We hypothesize that HFNC decreases rates of intubation in infants with bronchiolitis by decreasing the respiratory rate and work of breathing by providing a comfortable and well-tolerated means of noninvasive ventilatory support.

[Noninvasive mechanical ventilation in paediatric intensive care units: which indications in 2010?]

Noninvasive ventilation (NVI) is increasingly used in paediatrics, although there is a high variety of practices and a paucity of published data in paediatrics. The last French consensus conference recognized a specific role of NVI for infants suffering from acute bronchiolitis with apnoea, and acute respiratory failure due to laryngotracheomalacia and cystic fibrosis. NVI is feasible and can be beneficial in paediatric acute respiratory failure during neuromuscular diseases. Like in adults, its place in other diseases such as acute bronchoalveolitis without apnoea, acute respiratory failure during neuromuscular diseases, status asthmaticus, acute respiratory distress syndrome (ARDS) and postextubation respiratory failure is growing, even though not always defined. All these adult recommendations have not been validated in the pediatric setting, and, thus, taking the paediatric characteristics into account is essential. In 2010, NVI had an important place in PICU, and must be managed by a trained team whose practice is regularly evaluated.