|Year : 2020 | Volume
| Issue : 4 | Page : 168-173
Comparison of high-flow nasal cannula and noninvasive positive pressure ventilation in children with acute bronchiolitis
Anil Sachdev, Rohit Vohra, Neeraj Gupta, Dhiren Gupta, Suresh Gupta
Department of Pediatrics, Institute of Child Health, Sir Ganga Ram Hospital, New Delhi, India
|Date of Submission||12-Apr-2020|
|Date of Decision||30-Apr-2020|
|Date of Acceptance||09-May-2020|
|Date of Web Publication||13-Jul-2020|
Dr. Anil Sachdev
Department of Pediatrics, Institute of Child Health, Sir Ganga Ram Hospital, New Delhi - 110 060
Source of Support: None, Conflict of Interest: None
Objective: In recent years, there has been an increase in the use of noninvasive positive pressure ventilation (NIPPV) and high-flow nasal cannula (HFNC) in children with increased work of breathing due to acute bronchiolitis. However, there are only limited studies comparing the efficacy of these two interventions. This study was done to compare efficacy and patients' comfort while receiving HFNC and NIPPV for acute bronchiolitis.
Materials and Methods: Children admitted with the first episode of acute bronchiolitis with respiratory distress (modified Wood's Clinical Asthma Score >3) were randomized to receive NIPPV and HFNC. FiO2was titrated to achieve a SpO2of ≥94%. If the child was agitated and had a COMFORT B score of ≥17, dexmedetomidine infusion was started. The protocol lasted for at least 24 h or till the respiratory support was required as decided by the treating physician. Outcome parameters measured were failure of intervention and patient comfort (using COMFORT B scores). Social science system version SPSS 17.0 was used for statistical testing.P < 0.05 was taken to indicate a significant difference for all statistical tests.
Results: Twenty-five cases were enrolled in each study group. Failure of therapy was noted in 11 (44%) patients in the HFNC group and 6 (24%) in the NIPPV group (P = 0.18). COMFORT B score was significantly better in the HFNC group as compared to the NIPPV group (NIPPV12 vs. HFNC 8;P < 0.001). A number of cases requiring sedation and duration of sedation (dexmedetomidine) were more in the NIPPV group as compared to the HFNC group (22 vs. 10, P = 0.02, and 31.2 vs. 20.6 h, P = 0.04).
Conclusion: This study suggests that possibly HFNC and NIPPV are equally efficient in the treatment of moderate-to-severe bronchiolitis. HFNC is more comfortable for bronchiolitis patients in comparison to NIPPV.
Keywords: Bronchiolitis, high-flow nasal cannula, noninvasive positive pressure ventilation, respiratory support
|How to cite this article:|
Sachdev A, Vohra R, Gupta N, Gupta D, Gupta S. Comparison of high-flow nasal cannula and noninvasive positive pressure ventilation in children with acute bronchiolitis. J Pediatr Crit Care 2020;7:168-73
|How to cite this URL:|
Sachdev A, Vohra R, Gupta N, Gupta D, Gupta S. Comparison of high-flow nasal cannula and noninvasive positive pressure ventilation in children with acute bronchiolitis. J Pediatr Crit Care [serial online] 2020 [cited 2020 Aug 13];7:168-73. Available from: http://www.jpcc.org.in/text.asp?2020/7/4/168/289524
| Introduction|| |
Acute bronchiolitis is one of the most common respiratory system syndromes involving children <2 years of age. General supportive measures including respiratory support are the mainstay of treatment, as the evidence shows that most pharmacological interventions are not efficacious.
Historically, a high number of children with bronchiolitis developing respiratory failure required invasive mechanical ventilation. This led to invasive ventilation-related complications, prolonged stay in the pediatric intensive care unit (PICU), and increase in length of stay in PICU and hospital. In recent years, there has been an increase in the use of noninvasive positive pressure ventilation (NIPPV) and high-flow nasal cannula (HFNC) in bronchiolitis.,,,,
Many small prospective studies,, as well as two large retrospective studies, found that both NIPPV and HFNC in comparison to conventional oxygen therapy improved respiratory rates (RRs), oxygenation, and work of breathing in children with severe bronchiolitis. Despite showing clear benefits in oxygenation and ventilation, NIPPV restricts mobilization, limits oral nutrition, and is not tolerated by some patients due to discomfort. A high flow of heated and humidified air-oxygen mixture is delivered through nasal prongs by HFNC. It generates some positive airway pressure, reduces respiratory dead space, airway resistance, and less frequent interruption of therapy.
There are only limited studies comparing the efficacy of NIPPV and HFNC in adults and children with acute respiratory failure.,,, The main objective of the study was to compare the efficacy of HFNC and NIPPV with nasal mask interface therapy in children with acute bronchiolitis. The secondary objectives were to compare the patient comfort and related complications with the use of HFNC and NIPPV.
| Materials and Methods|| |
This was a prospective randomized study done from April 2017 to March 2018 in the 12-bed multidisciplinary pediatric critical care unit (PICU) at an academic, tertiary care hospital in Delhi. Ethical clearance and approval from the institutional ethical committee was taken.
All children aged from 1 month to 2 years admitted in the PICU with clinical diagnosis of the first episode of bronchiolitis and moderate-to-severe respiratory distress, defined by a modified Wood's Clinical Asthma Score (mWCAS) >3, were included in this study.
Bronchiolitis was defined as constellation of clinical symptoms and signs including a viral upper respiratory prodrome (rhinorrhea and cough), followed by tachypnea, increased respiratory effort (manifested as grunted, nasal flaring, and intercostal and/or subcostal retractions), and wheezing in children <2 years of age.
The exclusion criteria included following: children aged <1 month or > 2 years, comorbid conditions like chronic lung disease, cardiac or neuromuscular disorders and air leak syndrome like pneumothorax, pneumomediastinum, hemodynamically unstable children, and patients in need for imminent endotracheal intubation.
Patients were randomized into two groups (Group A and Group B) by block randomization which was performed by a computer-generated randomization algorithm. Patients satisfying the inclusion criteria and consenting to the study were randomized to receive either NIPPV (Group A) or HFNC (Group B).
Baseline observations were made for 15 min after arrival at PICU to collect RR, heart rate (HR), blood pressure, capillary filling time, mWCAS, and pain and discomfort using the comfort behavior (COMFORT B) score. A mixture of air/oxygen was provided by face mask/oxygen hood/OxyMask, (Oxy type Pediatric 7', OT1125-81, Southmedic, Canada), at a flow rate to maintain SpO2 of ≥94%.
When a child met the inclusion criteria, respiratory support was randomly allocated as NIPPV or HFNC by block randomization. Noninvasive ventilation (NIV) was delivered by Maquet critical care AB ventilator (Maquet, Germany) with nasal interface with a maximum expiratory pressure set at 8 cmH2O and maximum inspiratory pressure of 18 cmH2O.
The HFNC device, Optiflow (Fisher and Paykel, Villebon, France), was used. A maximum flow of 2 L/kg/min was delivered, with the device equipped with a pressure release valve set at 45 cmH2O. In both the groups, FiO2 was titrated to achieve a SpO2 of ≥94%, as usually recommended in PICUs, and the humidifier was auto set at 37°C. If the child was getting irritable or agitated and had a COMFORT B score of ≥17, dexmedetomidine infusion was started with a maximum dose of up to 1 mcg/kg/h for sedation.
The COMFORT B scale consists of six behavioral items: alertness, calmness, respiratory response (for ventilated children) or crying (for spontaneously breathing children), body movements, facial tension, and muscle tone and is validated to be used in ventilated and nonventilated critically ill children.,
The protocol lasted for at least 24 h or till the respiratory support was required as decided by the treating physician. The patient was declared free from support if no device was used for 24 h. In both the groups, RR, HR, mWCAS, COMFORT B score, FiO2, SpO2, pH, PCO2, and PaO2 were systematically assessed and recorded at 1, 12, 24, and 48 h after the start of the procedure. Chest X-ray was done at the start of therapy if not done at admission and at 24 h after enrollment as per unit protocol.
Detailed information on the protocol was given to the nursing teams in the PICU to ensure that a doctor on duty was notified as soon as the continuous monitoring or score indicates worsening in a child's condition. A child with persisting hypoxemia and/or hypercapnia despite the use of HFNC or NIPPV was considered for endotracheal intubation and mechanical ventilation. At any moment during this period, occurrence of at least one failure criterion justified a switch to the alternative respiratory support.
Intervention failure criteria
Failure of allocated intervention was defined by the occurrence of one of the following criteria: 1-point increase in mWCAS from the baseline score, RR rise >25% from baseline, RR >60 min, 5-point rise in COMFORT B score from baseline score, COMFORT B score >17 despite the use of dexmedetomidine (1 mcg/kg/h), hemodynamic instability, apnea episode, need to switch to alternate respiratory support, and any other situation requiring endotracheal intubation.
For the sample size calculation, with reference to a previous study, a difference of 15% in successful treatment between the two groups was considered. Using a two-tailed alpha value (0.05) and a beta value (0.2), 60 patients per group would be sufficient to detect a significant difference. Since this was a time-bound, 1-year study, we could enroll 25 cases in each intervention arm.
Social science system version SPSS 17.0 (SPSS Inc, Chicago, IL, USA) was used for statistical testing. Continuous variables were presented as mean ± standard deviation or median (interquartile range) for nonnormally distributed data. Categorical variables were expressed as frequencies and percentages. A Student's t-test was used for comparison of normally distributed continuous variables between the groups. Nominal categorical data between the groups were compared using the Chi-squared test or Fisher's exact test as appropriate. The Mann–Whitney U-test was used for comparison of nonnormal distribution continuous variables. P < 0.05 was taken to indicate a significant difference for all statistical tests.
| Results|| |
During the study period, 758 patients were admitted to our PICU, and out of which, 696 children did not meet the inclusion criteria and 12 children were excluded. The study group was comprised of 50 children and was randomized into two groups of 25 each [Figure 1]. Baseline demographic characters and vital signs at the time of admission were comparable in both the groups, as shown in [Table 1].
|Figure 1: Study flowchart. NIV: Noninvasive ventilation, HFNC: High-flow nasal cannula, ET: Endotracheal|
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|Table 1: Baseline characteristics of noninvasive ventilation positive pressure ventilation group and high-flow nasal cannula group|
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After institution of the study protocol, vital signs and arterial blood gas analysis were done at 1, 12, 24, and 48 h of the study period. There were no statistically significant differences in HR, RR, PaCO2, and PaO2/FiO2 ratio in the two study groups [Figure 2].
|Figure 2: Comparison of heart rate, respiratory rate, PO2/FiO2, and PCO2 ratio in two intervention groups at different time periods|
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The number of children requiring sedation and duration of sedation (dexmedetomidine) was significantly higher in the NIPPV group as compared to the HFNC group (22 vs. 10, P = 0.02, and 31.2 h vs. 20.6 h, P = 0.04). Moreover, COMFORT B scores were significantly lower in the HFNC group when compared to the NIPPV group at 12, 24, and 48 h of study period [Table 2].
|Table 2: COMFORT B score in high-flow nasal cannula and noninvasive ventilation positive pressure ventilation study groups|
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Failure of therapy
Failure of therapy was noted in 11 (44%) patients in the HFNC group and 6 (24%) in NIPPV cases, but the difference was not statically significant (P = 0.18) [Figure 1] and [Figure 3]. 76.5% of failures occurred within the first 24 h of starting intervention therapy (HFNC group: 63.6% and NIPPV group: 100%). The most common cause of failure was increase in RR (88.2%), followed by increase in mWCAS (82.3%) and need for endotracheal intubation (76.5%). One child did not tolerate NIPPV (rise in COMFORT B score >17 even after using dexmedetomidine) so was shifted to HFNC and successfully managed.
|Figure 3: Kaplan–Meier survival analysis between freedom of failure and total duration of support in high-flow nasal cannula and noninvasive ventilation groups|
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| Discussion|| |
We conducted a randomized controlled trial to compare the efficacy and comfort of patients with acute bronchiolitis while receiving HFNC or NIPPV. There was no difference in the efficacy of HFNC and NIPPV in relieving the tachycardia and tachypnea and to improve the blood gas status. There were few failures in the NIPPV group as compared to HFNC cases but did not reach level of significance. Twenty-seven percent of HFNC failure cases were successfully treated with NIPPV. HFNC was found to be more comfortable for patients and significantly less number of children required sedation and the duration of sedation was shorter in this group.
Acute bronchiolitis in children <2 years of age is a frequent cause of hospital admission. The management of bronchiolitis depends on the severity of the illness. In most cases, it can be managed by supportive care; however, severe illness requires hospitalization including PICU care.
We excluded children with comorbid conditions, chronic lung disease, congenital heart disease, or neuromuscular disorders. The respiratory mechanics and pathophysiology of these conditions would profoundly affect the outcome of bronchiolitis. Similarly, patients with the first episode of bronchiolitis were enrolled. It is difficult to differentiate infants with repeated episodes of bronchiolitis from reactive airway disease children.
The use of NIPPV in bronchiolitis has several advantages such as unloading of respiratory muscles, increased expiratory time, and improvement in RRs.,, Several recent studies have reported that NIPPV through nasal continuous positive airway pressure (nCPAP) reduces duration of ventilation and hospital stay as compared to invasive mechanical ventilation. Thus, nCPAP is being increasingly used, and it is currently considered the gold standard respiratory support in children with moderate-to-severe bronchiolitis.
HFNC delivers a heated and humidified mixture of air and oxygen at a flow rate which is higher than the patient's inspiratory flow. It is being increasingly used in PICUs due to its beneficial effects on the work of breathing, lung volumes, the ease of installation, and the good tolerance. HFNC therapy in bronchiolitis has shown improvement in RRs, work of breathing, and decreased need of invasive mechanical ventilation.,
Two studies comparing NIPPV with HFNC therapy in bronchiolitis had conflicting results. Metge et al. compared HR, RR, FiO2, SpO2, PCO2, pH, and length of PICU stay in children of acute bronchiolitis receiving nCPAP and HFNC and found no difference in RR, HR, FiO2, and CO2 evolution, oxygen weaning, or length of PICU stay in the two groups.
Milési et al. conducted a multicenter randomized controlled trial to compare nCPAP with HFNC in infants with moderate-to-severe acute bronchiolitis and found that HFNC is not as effective as nCPAP as the initial respiratory support for young infants with moderate-to-severe bronchiolitis.
Overall, it was seen that HFNC therapy was more comfortable for children as manifested by low COMFORT B score and decreased need of sedation in the HFNC group as compared to the NIPPV group.
There are certain limitations and strengths of our study. The main limitation is underpowered sample size which was due to predetermined time allotted for case enrollment. Bronchiolitis is a seasonal disease with more cases occurring in the winter season. We enrolled patients during one season only, and cases admitted in the PICU were evaluated for enrollment. Moreover, due to block randomization, there is a possibility that a child may be potentially overtreated or undertreated since the severity of illness was not considered while allotting a particular intervention. This was not a blinded study, so the treating clinician's bias cannot be ruled out. The strengths of this randomized trial include predefined diagnostic and inclusion criteria, and objective scales were used to categorize the severity of work of breathing and patients' comfort.
| Conclusion|| |
NIPPV and HFNC are possibly equal in efficiency in the treatment of moderate-to-severe bronchiolitis. This study shows that HFNC is more comfortable for bronchiolitis patients in comparison to NIV.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Nichols DG, Shaffner DH. Pneumonia and bronchiolitis. In: Rogers' Textbook of Pediatric Intensive Care. 5th
ed., Ch. 48. Philadelphia: Lippincott Williams and Wilkins; 2016. p. 745-65.
American Academy of Pediatrics Subcommittee on Diagnosis and Management of Bronchiolitis. Diagnosis and management of bronchiolitis. Pediatrics 2006;118:1774-93.
Cambonie G, Milési C, Jaber S, Amsallem F, Barbotte E, Picaud JC, et al
. Nasal continuous positive airway pressure decreases respiratory muscles overload in young infants with severe acute viral bronchiolitis. Intensive Care Med 2008;34:1865-72.
Thia LP, McKenzie SA, Blyth TP, Minasian CC, Kozlowska WJ, Carr SB. Randomised controlled trial of nasal continuous positive airways pressure (CPAP) in bronchiolitis. Arch Dis Child 2008;93:45-7.
Milési C, Baleine J, Matecki S, Durand S, Combes C, Novais AR, et al
. Is treatment with a high flow nasal cannula effective in acute viral bronchiolitis? A physiologic study. Intensive Care Med 2013;39:1088-94.
Larrar S, Essouri S, Durand P, Chevret L, Haas V, Chabernaud JL, et al
. Effects of nasal continuous positive airway pressure ventilation in infants with severe acute bronchiolitis. Arch Pediatr 2006;13:1397-403.
McKiernan C, Chua LC, Visintainer PF, Allen H. High flow nasal cannulae therapy in infants with bronchiolitis. J Pediatr 2010;156:634-8.
Azevedo JR, Montenegro WS, Leitao AL, Siva MM, Prazeres JS, Maranhao JP, et al
. High flow nasal cannula oxygen (HFNC) versus non-invasive positive pressure ventilation (NIPPV) in acute hypoxemic respiratory failure: A pilot randomized controlled trial. Intensive Care Med Exp 2015;3 Suppl 1:A166.
Shen Y, Zhang W. High-flow nasal cannula versus non invasive positive pressure ventilation in acute respiratory failure: Interaction between PaO2/FiO2 and tidal volume. Crit Care 2017;21:285.
Metge P, Grimaldi C, Hassid S, Thomachot L, Loundou A, Martin C, et al
. 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. Eur J Pediatr 2014;173:953-8.
Milési C, Essouri S, Pouyau R, Liet JM, Afanetti M, Portefaix A, et al
. 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). Intensive Care Med 2017;43:209-16.
Hollman G, Shen G, Zeng L, Yngsdal-Krenz R, Perloff W, Zimmerman J, et al
. Helium-oxygen improves clinical asthma scores in children with acute bronchiolitis. Crit Care Med 1998;26:1731-6.
Boerlage AA, Ista E, Duivenvoorden HJ, de Wildt SN, Tibboel D, van Dijk M. The COMFORT behaviour scale detects clinically meaningful effects of analgesic and sedative treatment. Eur J Pain 2015;19:473-9.
Sharma BS, Gupta MK, Rafik SP. Hypertonic (3%) saline vs 0.93% saline nebulization for acute viral bronchiolitis: A randomized controlled trial. Indian Pediatr 2013;50:743-7.
Wu S, Baker C, Lang ME, Schrager SM, Liley FF, Papa C, et al
. Nebulized hypertonic saline for bronchiolitis: A randomized clinical trial. JAMA Pediatr 2014;168:657-63.
Ista E, van Dijk M, Tibboel D, de Hoog M. Assessment of sedation levels in pediatric intensive care patients can be improved by using the COMFORT “behaviour” scale. Pediatr Crit Care Med 2005;6:58-63.
[Figure 1], [Figure 2], [Figure 3]
[Table 1], [Table 2]