- Email: [email protected]
Oxygen in Acute Bronchiolitis
Accepted Manuscript Oxygen in Acute Bronchiolitis
Julia Fuzak Freeman, Lalit Bajaj PII: DOI: Reference:
S1522-8401(18)30010-7 doi:10.1016/j.cpem.2018.02.010 YCPEM 651
To appear in: Please cite this article as: Julia Fuzak Freeman, Lalit Bajaj , Oxygen in Acute Bronchiolitis. The address for the corresponding author was captured as affiliation for all authors. Please check if appropriate. Ycpem(2018), doi:10.1016/j.cpem.2018.02.010
This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
ACCEPTED MANUSCRIPT Title: Oxygen in Acute Bronchiolitis Authors: Julia Fuzak Freeman, MD Assistant Professor of Pediatrics and Emergency Medicine
IP
T
Section of Emergency Medicine/Department of Pediatrics
CR
University of Colorado School of Medicine Aurora, CO 80045
US
Phone: 773-304-7309 Fax: 720-777-7317
M
AN
Email: [email protected]
Lalit Bajaj, MD, MPH
ED
Corresponding author:
PT
Professor of Pediatrics and Emergency Medicine
CE
Section of Emergency Medicine/Department of Pediatrics University of Colorado School of Medicine
AC
Aurora, CO 80045
Phone: 720-777-7214 Fax: 720-777-7300 Email: [email protected]
1
ACCEPTED MANUSCRIPT Abstract Bronchiolitis is the most common cause of hospital admission in children under the age of 1 in developed nations. Admissions for bronchiolitis sharply increased in the late 1980s and 90s and it is widely accepted that much of that increase was due to use of noninvasive
IP
T
assessment of oxygen saturation (Sp02) via pulse oximetry. This was combined with the
CR
creation of SpO2 cutoffs that would require hospitalization for supplemental oxygen. Pulse oximetry often influences the decision to admit and can lead to prolonged hospitalization for
US
supplemental oxygen, often after work of breathing has resolved.(3,4) In this article, we will review the data describing how oxygen saturation influences the decision to admit and length
AN
of hospitalization. We will then review the evidence supporting the use of supplemental oxygen
M
in the home setting to avoid hospitalization and recent data on the incidence of hypoxia in
ED
these infants and its relationship to short term outcomes. We will conclude with a comment on
PT
further research and quality improvement work that is needed in this area.
AC
CE
Key words: Bronchiolitis, oxygen, emergency department, hypoxia, pulse oximetry
2
ACCEPTED MANUSCRIPT Bronchioiitis is the most common cause for hospitalization in children less than 1 year of age in developed countries. Respiratory syncytial virus (RSV), one of the most common causes of bronchiolitis, results in more than 2.1 million outpatient visits and 57,527 hospitalizations in children under five years of age, annually.(1) Shay et al demonstrated a sharp increase (152%)
IP
T
in hospital admissions from 1980 to 1996 amongst infants under one year of age.(2) Theories
CR
regarding the source for this sharp increase include increased virulence of RSV, increased survival of premature infants with chronic lung disease, and a variety of others.(2) As more
US
evidence has emerged, the most likely root cause has been postulated to be the ubiquitous use of pulse oximetry in the care of these infants; along with the subsequent development of
AN
arbitrary oxygenation (SpO2) cutoffs indicating need for hospitalization.(3,5) Other postulated
M
contributing factors were the increasing use of β-agonists and chest radiographs; which may
ED
often dictate the need for admission for presumed “response” to therapy or the need to treat a “suspected pneumonia” on chest radiograph.
PT
While bronchiolitis admission rates have been shown to be decreasing in recently
CE
published studies, costs associated with bronchiolitis hospitalizations among non-high risk infants and children continue to rise ($5432/admit in charges in 1997 increasing to
AC
$10,289/admit in 2012) despite little change in associated morbidity and mortality and a decrease in median length of stay (LOS; 2.28 days in 1997 vs 1.96 days in 2012).(6,7) The publication and local implementation of a 2006 American Academy of Pediatrics (AAP) clinical care guideline may have had some impact on the noted decrease; this guideline was subsequently updated in 2014.(8,9) There has been noted improvement in adherence to these guidelines, but other than home oxygen therapy, which will be discussed further below, no
3
ACCEPTED MANUSCRIPT specific intervention or decrease in intervention has been noted to result in a decrease in hospital admissions.
PULSE OXIMETRY UTILIZATION AND INFLUENCE ON ADMISSION RATES AND LOS
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T
Pulse oximetry is frequently used as the fifth vital sign in assessment of patients with
CR
respiratory complaints with small changes in SpO2 driving medical decision making despite a well known lack of precision in the 76-90% range and manufacturer-described +/- 2 point
US
margin of error which limits its clinical utility in the hypoxemic patient.(10) Despite these limitations and a lack of evidence-based parameters, studies have shown that pulse oximetry
AN
often carries more weight in clinical decision-making than our clinical exam. In 2003, Mallory et
M
al published the results of a survey of pediatric emergency medicine practitioners.(3) Survey
ED
respondents were asked to determine their admission decision and it was noted that a change in the hypothetical patient’s oxygen saturation from 94 to 92% with no other changes, resulted
PT
in a two-fold increase in admission (43% to 83%). This observation was further reinforced in
CE
2014, when Schuh et al published the results of a study of providers admission decisions.(5) In this study, SpO2 values were altered in a randomized double-blind parallel clinical study, and
AC
patients with SpO2 values artificially altered to be 3% higher were 16% less likely to admitted, despite the same clinical exam. While perceived hypoxemia appears to be largely driving the decision to admit, infants also remain hospitalized after other parameters such as feeding and hydration and work of breathing have improved. In a 2008 retrospective analysis of patients admitted for bronchiolitis, Unger et al found that patients stayed an average of 2.75 days past the time other clinical
4
ACCEPTED MANUSCRIPT parameters had improved. In another study published in 2015, Cunningham et al (11) randomly allocated patients who had been admitted to either a standard pulse oximeter or one that had been altered to read 4% percentage points higher. The group who had artificially altered Sp0 2 had less supplemental oxygen prescribed, fewer adverse events and ICU admissions, and a
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T
hospital LOS. This study was prompted by a discrepancy in recommendations for supplemental
CR
oxygen therapy between UK and US guidelines; the UK guideline suggested 94% while recommendations from the AAP suggested 90%. (9) In the most recent update of the UK
US
guideline, 92% is now recommended.(12)
It is not surprising that with no agreement on a recommendation for what constitutes
AN
hypoxia necessitating supplemental oxygen, and a lack of evidence that outcomes are improved
M
with more supplemental oxygen, that is there is such substantial variation in management.
ED
Another management strategy that has been investigated is whether continuous SpO2 measurement vs intermittent measurement has any impact on outcomes. In 2015, McCulloh et
PT
al published data from a series of hospitalized patients comparing intermittent versus
CE
continuous pulse oximetry, and found no change in adverse events or LOS.(13)
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HOME OXYGEN THERAPY
Management of supplemental oxygen as a potential out-of-hospital therapy has emerged as one strategy aimed at improving the treatment, disposition, and inpatient LOS of patients with bronchiolitis and hypoxemia. The first description of home oxygen therapy (HOT) being used on discharge from an emergency department (ED) in the US was in 2006 when Bajaj et al published a trial of patients of 37 patients who successfully completed a predetermined
5
ACCEPTED MANUSCRIPT observation of 8 hours.(14) One patient returned and had an uncomplicated hospital course. This was the first description of the feasibility of HOT for bronchiolitis for children discharged from an ED setting. It was part of randomized trial of patients who were treated with traditional inpatient admission for supplemental oxygen. This group of investigators went on to institute a
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treatment pathway for home oxygen from the ED. (Figure 1) The pathway set the SpO2
CR
threshold at less than 88%. In 2012, Halstead et al published a retrospective study of this pathway, including nearly 4200 ED bronchiolitis visits, with 649 children discharged on
US
supplemental oxygen, and reported on disposition and outcomes for these patients.(15) They found ED discharge on HOT safely reduced the hospitalization rate for these patients from 40 to
AN
31%. There was no difference in return visits between patients discharged on RA versus those
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sent home on oxygen. It is important to note that this institution is located at an elevation of
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1600 m (5280 ft), and that discharge home from the inpatient units on HOT was already a common practice at this institution. .
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The start of a program to discharge infants after a 24-hour observation period has also
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been described along with an analysis of the barriers to success. In 2010, Sandweiss et al published data from a survey of physicians at their institution inquiring what the perceived
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barriers were to discharge.(16) “Hypoxia” was the primary barrier reported most frequently, and was also a common co-factor when other barriers were identified, such as need for deep nasal suctioning. This group then published a related survey of general pediatricians in 2012, founding that most of those with experience caring patients on HOT post discharge lived at higher altitudes, and most found it difficult to decide when to stop the supplemental oxygen.(17) In 2013, Sandweiss et al published results from the implementation of a HOT
6
ACCEPTED MANUSCRIPT protocol that resulted in an increase in admitted children discharged within 24 hours from 20.0 to 38.4%.(18) Concern about the safety of HOT has been described as a barrier to its use. However, when pooled, the four published studies of ED discharge on HOT have demonstrated a low rate
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of return and admission (4.9-9.4%) This is similar to the rate of return visits and admission for
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patients with bronchiolitis who were discharged on room air. There was also a low rate of adverse events with HOT. Only 1 out of 1145 home oxygen patients subsequently required
US
mechanical ventilation.(14,15,19,20) (Table 1) ED discharge on HOT has also been associated with high levels of caregiver comfort and satisfaction, with 88% of caregivers preferring home
AN
oxygen to hospitalization.(14,20) However, all published studies of ED discharge on HOT for
M
bronchiolitis have been performed at relatively high altitude (over 5200 ft or 1585 m) and
ED
current use remains primarily limited to these geographic areas. However, in 2009, Tie et al described patients in Australia that were discharged on HOT after 24 hours of inpatient
PT
care.(21) This study included home nursing visits, and referred to the home setting as “hospital
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in the home.” This same center then published results from a program they created called “Hospital in the Home Oxygen (HiTHOx) Program.”(22) This program looked at patients who
AC
completed a 12-hour period in the hospital prior to being discharged. One hundred and twelve patients were enrolled and the return rate was 6% with no adverse outcomes. As mentioned above, the literature for HOT from the ED is primarily from high altitude metropolitan locations, and this has raised concerns about implementing a system at lower altitudes. One of the foremost criticisms has historically been the unclear correlation between disease severity, degree of hypoxemia, and altitude. The American Academy of Pediatrics’
7
ACCEPTED MANUSCRIPT clinical practice guideline for the diagnosis, management and prevention of bronchiolitis, suggested the use of a pulse oximetry (SpO2) value of 90% as a threshold for initiation of supplemental oxygen and a 2015 survey of pediatric emergency medicine physicians showed a relative national consensus on this threshold.(9, 23) While current use of HOT at ED discharge
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remains low at sea-level locales, most (85%) providers recognized it as safe in the 2015 survey.
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Fifty-four percent felt it would be feasible at their institution, but readiness for implementation was poor. Major barriers to implementation noted in the survey included: lack of support, lack
US
of home health agencies equipped to provide outpatient oxygen to pediatric patients, lack of
AN
ED observation space, difficulty arranging home oxygen, and caregiver education concerns.(23)
M
HYPOXIA AND OUTCOMES
ED
Most providers understand that the evaluation of the infant with bronchiolitis in the ED is limited and that and we are likely catching episodes of hypoxia that are occurring normally
PT
outside of the care setting. In fact, some oxygen desaturations are likely normal (healthy infants
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have desaturations during sleep.(24) Some studies have shown lower mortality when oxygen saturations are maintained above 90% in premature infants,(25) and neurodevelopmental
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delays with mild desaturations in children with congenital heart disease,(26) or those living at high altitude.(27) However, these findings cannot necessarily be extrapolated to otherwise healthy infants whose temporary hypoxia is caused by a transient, acute respiratory illness. Additionally, mild hypoxemia associated with asthma, which may be more similar in its transient nature to the hypoxemia associated with bronchiolitis, has not been shown to lead to any long term neurocognitive deficits.(28) However, other studies of children with asthma have
8
ACCEPTED MANUSCRIPT suggested an association between hypoxemia and behavioral problems.(26) Recently, a compelling study by Principi et al followed well-appearing infants with bronchiolitis who were not hypoxic at their ED visit and were discharged home on room air.(29) Many of these patients had SpO2 desaturations at home with many of these described as significant (greater
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than 1 minute at SpO2 <70% or greater than 3 minutes at SpO2 <90%). Ten percent of subjects
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spent more than 10% of the time with a SpO2 less than 90%). In this study the rate of unscheduled return visits and hospitalization was similar for both hypoxic and non-hypoxic
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infants. This data combined with clinical experience with these patients suggests we may be overtreating what are likely expected episodes of transient hypoxia that may not have any
ED
QUALITY IMPROVEMENT EFFORTS
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untoward effects.
In 2013, the Choosing Wisely Campaign came forth with a recommendation to not use
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continuous pulse oximetry routinely in children with acute respiratory illness unless they are on
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supplemental oxygen.(30) Despite the fact that quality improvement efforts to improve care of children with acute respiratory illnesses have been increasing in recent years, published reports
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of projects addressing the utilization of pulse oximetry are limited. In 2015, Schondelmeyer et al published their results from a QI intervention to decrease the use of continuous pulse oximetry.(31) While they did show a reduction in use from 10 hours to 3 hours, there was no associated change in LOS. The authors noted that there was still a significant impact from this work in terms of reducing alarm fatigue.
9
ACCEPTED MANUSCRIPT SUMMARY AND THOUGHTS FOR THE FUTURE The practice utilizing pulse oximetry as a tool to determine disposition in patients with bronchiolitis is likely leading to over-diagnosis of hypoxemia, over treatment, unnecessary hospitalization, and increased cost.(32) The significance of transient hypoxemia remains
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unclear. There is no consensus definition of transient, nor is there consensus on how low is too
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low, leading to a lack of evidence-based parameters for the use of pulse oximetry in the setting of acute respiratory illness. The AAP guidelines suggest that physicians may choose not to
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administer supplemental oxygen for saturations greater than 90%, and may choose not to use continuous pulse oximetry for infants with bronchiolitis, with a “weak” recommendation.
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Research and quality improvement efforts are needed to expand the evidence base to support
M
these or different recommendations. As the routine use of pulse oximetry seems difficult to
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reduce, it may be useful to begin to try to use the Sp02 as just one factor amongst the entire clinical picture to make more data-driven decisions. Because so many children are admitted and
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stay in the hospital, home oxygen therapy remains a practical and safe alternative to
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hospitalization; and needs further evaluation including centers at sea level altitudes.
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ACCEPTED MANUSCRIPT References 1.
Centers for Disease Control and Prevention. Respiratory syncytial virus infection: trends and surveillance 2017. Avsailable at: https://www.cdc.gov/rsv/research/ussurveillance.html - f1. Accessed February 3rd, 2018, 2018.
T
Shay DK, Holman RC, Newman RD, et al. Bronchiolitis-associated hospitalizations among
3.
CR
US children, 1980-1996. JAMA 1999;282(15):1440-1446.
IP
2.
Mallory MD, Shay DK, Garrett J, Bordley WC. Bronchiolitis management preferences and
US
the influence of pulse oximetry and respiratory rate on the decision to admit. Pediatrics 2003;111(1):e45-51.
Unger S, Cunningham S. Effect of oxygen supplementation on length of stay for infants
AN
4.
Schuh S, Freedman S, Coates A, et al. Effect of oximetry on hospitalization in
ED
5.
M
hospitalized with acute viral bronchiolitis. Pediatrics 2008;121(3):470-475.
bronchiolitis: a randomized clinical trial. JAMA 2014;312(7):712-718. Doucette A, Jiang X, Fryzek J, et al. Trends in respiratory syncytial virus and bronchiolitis
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6.
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hospitalization rates in high-risk infants in a United States nationally representative database, 1997-2012. PloS One 2016;11(4):e0152208. Hasegawa K, Tsugawa Y, Brown DF, et al. Temporal trends in emergency department
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7.
visits for bronchiolitis in the United States, 2006 to 2010. Pediatr Infects Dis J 2014;33(1):11-18. 8.
American Academy of Pediatrics Subcommittee on Diagnosis and Management of Bronchiolitis. Diagnosis and management of bronchiolitis. Pediatrics 2006;118(4):17741793.
11
ACCEPTED MANUSCRIPT 9.
Ralston SL, Lieberthal AS, Meissner HC, et al. Clinical practice guideline: the diagnosis, management, and prevention of bronchiolitis. Pediatrics 2014;134(5):e1474-1502.
10.
Hendaus MA, Jomha FA, Alhammadi AH. Pulse oximetry in bronchiolitis: is it needed? Ther Clin Risk Manag 2015;11:1573-1578.
T
Cunningham S, Rodriguez A, Adams T, et al. Oxygen saturation targets in infants with
IP
11.
CR
bronchiolitis (BIDS): a double-blind, randomised, equivalence trial. Lancet 2015;386(9998):1041-1048.
Ricci V, Delgado Nunes V, Murphy MS, Cunningham S. Bronchiolitis in children: summary
US
12.
of NICE guidance. BMJ (Clinical research ed) 2015;350:h2305. McCulloh R, Koster M, Ralston S, et al. Use of intermittent vs continuous pulse oximetry
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13.
M
for nonhypoxemic infants and young children hospitalized for bronchiolitis: a
14.
ED
randomized clinical trial. JAMA Pediatr 2015;169(10):898-904. Bajaj L, Turner CG, Bothner J. A randomized trial of home oxygen therapy from the
Halstead S, Roosevelt G, Deakyne S, Bajaj L. Discharged on supplemental oxygen from an
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15.
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emergency department for acute bronchiolitis. Pediatrics 2006;117(3):633-640.
emergency department in patients with bronchiolitis. Pediatrics 2012;129(3):e605-610. Sandweiss DR, Corneli HM, Kadish HA. Barriers to discharge from a 24-hour observation
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16.
unit for children with bronchiolitis. Pediatr Emerg Care 2010;26(12):892-896. 17.
Sandweiss DR, Kadish HA, Campbell KA. Outpatient management of patients with bronchiolitis discharged home on oxygen: a survey of general pediatricians. Clin Pediatr. 2012;51(5):442-446.
12
ACCEPTED MANUSCRIPT 18.
Sandweiss DR, Mundorff MB, Hill T, et al. Decreasing hospital length of stay for bronchiolitis by using an observation unit and home oxygen therapy. JAMA Pediatr 2013;167(5):422-428.
19.
Flett KB, Breslin K, Braun PA, Hambidge SJ. Outpatient course and complications
IP
T
associated with home oxygen therapy for mild bronchiolitis. Pediatrics 2014;133(5):769-
20.
CR
775.
Freeman JF, Deakyne S, Bajaj L. Emergency department-initiated home oxygen for
US
bronchiolitis: a prospective study of community follow-up, caregiver satisfaction, and outcomes. Acad Emerg Med 2017;24(8):920-929
Tie SW, Hall GL, Peter S, et al. Home oxygen for children with acute bronchiolitis. Arch
AN
21.
Zappia T, Peter S, Hall G, et al. Home oxygen therapy for infants and young children with
ED
22.
M
Dis Child 2009;94(8):641-643.
acute bronchiolitis and other lower respiratory tract infections: the HiTHOx program.
Freeman JF, Brou L, Mistry R. Feasibility and capacity for widespread use of emergency
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23.
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Issues Compr Pediatr Nurs 2013;36(4):309-318.
department-based home oxygen for Bronchiolitis. Am J Emerg Med 2017;35(9):1379-
24.
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1381.
Hunt CE, Corwin MJ, Lister G, et al. Longitudinal assessment of hemoglobin oxygen saturation in healthy infants during the first 6 months of age. Collaborative Home Infant Monitoring Evaluation (CHIME) Study Group. J Pediatr 1999;135(5):580-586.
25.
Stenson BJ, Tarnow-Mordi WO, Darlow BA, et al. Oxygen saturation and outcomes in preterm infants. NEJM 2013;368(22):2094-2104.
13
ACCEPTED MANUSCRIPT 26.
Bass JL, Corwin M, Gozal D, et al. The effect of chronic or intermittent hypoxia on cognition in childhood: a review of the evidence. Pediatrics 2004;114(3):805-816.
27.
Wehby GL. Living on higher ground reduces child neurodevelopment-evidence from South America. J Ppediatr 2013;162(3):606-611.e601.
T
Rietveld S, Colland VT. The impact of severe asthma on school children. J Asthma
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28.
29.
CR
1999;36(5):409-417.
Principi T, Coates AL, Parkin PC, et al. Effect of oxygen desaturations on subsequent
US
medical visits in infants discharged from the emergency department with bronchiolitis. JAMA Pediatr 2016;170(6):602-608.
Quinonez RA, Garber MD, Schroeder AR, et al. Choosing wisely in pediatric hospital
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30.
M
medicine: five opportunities for improved healthcare value. J Hosp Med 2013;8(9):479-
31.
ED
485.
Schondelmeyer AC, Simmons JM, Statile AM, et al. Using quality improvement to reduce
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continuous pulse oximetry use in children with wheezing. Pediatrics 2015;135(4):e1044-
Quinonez RA, Coon ER, Schroeder AR, Moyer VA. When technology creates uncertainty: pulse oximetry and overdiagnosis of hypoxaemia in bronchiolitis. BMJ 2017;358:j3850.
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32.
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1051.
14
ACCEPTED MANUSCRIPT Table 1. Review of patients discharged on home oxygen therapy from published studies.
Site of Observation Intubated (n)
Length of Observation
Oxygen Limit
Bajaj, 2006 2.7
37
2-24 months 0
ED
8 hours
1 L/min
Tie, 2009 4.5
22
3-24 months 0
Hospital
24 hours
1 l/min
Halstead, 2012 6
649
3-18 months 0
ED
8 hours
Zappia, 2013 6
112
> 2 months 0
Hospital
Fleet, 2014 9.4
253
2-24 months 0
ED
Freeman, 2017 4.9
225
3-18 months 1
ED
CR
IP
T
N Age Inclusion Return Admission (%)
1 l/min
4 hours
1 l/min
8 hours
0.5 l/min
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PT
ED
M
AN
US
12 hours
0.5 l/min
15
Figure 1
Julia Fuzak Freeman, Lalit Bajaj PII: DOI: Reference:
S1522-8401(18)30010-7 doi:10.1016/j.cpem.2018.02.010 YCPEM 651
To appear in: Please cite this article as: Julia Fuzak Freeman, Lalit Bajaj , Oxygen in Acute Bronchiolitis. The address for the corresponding author was captured as affiliation for all authors. Please check if appropriate. Ycpem(2018), doi:10.1016/j.cpem.2018.02.010
This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
ACCEPTED MANUSCRIPT Title: Oxygen in Acute Bronchiolitis Authors: Julia Fuzak Freeman, MD Assistant Professor of Pediatrics and Emergency Medicine
IP
T
Section of Emergency Medicine/Department of Pediatrics
CR
University of Colorado School of Medicine Aurora, CO 80045
US
Phone: 773-304-7309 Fax: 720-777-7317
M
AN
Email: [email protected]
Lalit Bajaj, MD, MPH
ED
Corresponding author:
PT
Professor of Pediatrics and Emergency Medicine
CE
Section of Emergency Medicine/Department of Pediatrics University of Colorado School of Medicine
AC
Aurora, CO 80045
Phone: 720-777-7214 Fax: 720-777-7300 Email: [email protected]
1
ACCEPTED MANUSCRIPT Abstract Bronchiolitis is the most common cause of hospital admission in children under the age of 1 in developed nations. Admissions for bronchiolitis sharply increased in the late 1980s and 90s and it is widely accepted that much of that increase was due to use of noninvasive
IP
T
assessment of oxygen saturation (Sp02) via pulse oximetry. This was combined with the
CR
creation of SpO2 cutoffs that would require hospitalization for supplemental oxygen. Pulse oximetry often influences the decision to admit and can lead to prolonged hospitalization for
US
supplemental oxygen, often after work of breathing has resolved.(3,4) In this article, we will review the data describing how oxygen saturation influences the decision to admit and length
AN
of hospitalization. We will then review the evidence supporting the use of supplemental oxygen
M
in the home setting to avoid hospitalization and recent data on the incidence of hypoxia in
ED
these infants and its relationship to short term outcomes. We will conclude with a comment on
PT
further research and quality improvement work that is needed in this area.
AC
CE
Key words: Bronchiolitis, oxygen, emergency department, hypoxia, pulse oximetry
2
ACCEPTED MANUSCRIPT Bronchioiitis is the most common cause for hospitalization in children less than 1 year of age in developed countries. Respiratory syncytial virus (RSV), one of the most common causes of bronchiolitis, results in more than 2.1 million outpatient visits and 57,527 hospitalizations in children under five years of age, annually.(1) Shay et al demonstrated a sharp increase (152%)
IP
T
in hospital admissions from 1980 to 1996 amongst infants under one year of age.(2) Theories
CR
regarding the source for this sharp increase include increased virulence of RSV, increased survival of premature infants with chronic lung disease, and a variety of others.(2) As more
US
evidence has emerged, the most likely root cause has been postulated to be the ubiquitous use of pulse oximetry in the care of these infants; along with the subsequent development of
AN
arbitrary oxygenation (SpO2) cutoffs indicating need for hospitalization.(3,5) Other postulated
M
contributing factors were the increasing use of β-agonists and chest radiographs; which may
ED
often dictate the need for admission for presumed “response” to therapy or the need to treat a “suspected pneumonia” on chest radiograph.
PT
While bronchiolitis admission rates have been shown to be decreasing in recently
CE
published studies, costs associated with bronchiolitis hospitalizations among non-high risk infants and children continue to rise ($5432/admit in charges in 1997 increasing to
AC
$10,289/admit in 2012) despite little change in associated morbidity and mortality and a decrease in median length of stay (LOS; 2.28 days in 1997 vs 1.96 days in 2012).(6,7) The publication and local implementation of a 2006 American Academy of Pediatrics (AAP) clinical care guideline may have had some impact on the noted decrease; this guideline was subsequently updated in 2014.(8,9) There has been noted improvement in adherence to these guidelines, but other than home oxygen therapy, which will be discussed further below, no
3
ACCEPTED MANUSCRIPT specific intervention or decrease in intervention has been noted to result in a decrease in hospital admissions.
PULSE OXIMETRY UTILIZATION AND INFLUENCE ON ADMISSION RATES AND LOS
IP
T
Pulse oximetry is frequently used as the fifth vital sign in assessment of patients with
CR
respiratory complaints with small changes in SpO2 driving medical decision making despite a well known lack of precision in the 76-90% range and manufacturer-described +/- 2 point
US
margin of error which limits its clinical utility in the hypoxemic patient.(10) Despite these limitations and a lack of evidence-based parameters, studies have shown that pulse oximetry
AN
often carries more weight in clinical decision-making than our clinical exam. In 2003, Mallory et
M
al published the results of a survey of pediatric emergency medicine practitioners.(3) Survey
ED
respondents were asked to determine their admission decision and it was noted that a change in the hypothetical patient’s oxygen saturation from 94 to 92% with no other changes, resulted
PT
in a two-fold increase in admission (43% to 83%). This observation was further reinforced in
CE
2014, when Schuh et al published the results of a study of providers admission decisions.(5) In this study, SpO2 values were altered in a randomized double-blind parallel clinical study, and
AC
patients with SpO2 values artificially altered to be 3% higher were 16% less likely to admitted, despite the same clinical exam. While perceived hypoxemia appears to be largely driving the decision to admit, infants also remain hospitalized after other parameters such as feeding and hydration and work of breathing have improved. In a 2008 retrospective analysis of patients admitted for bronchiolitis, Unger et al found that patients stayed an average of 2.75 days past the time other clinical
4
ACCEPTED MANUSCRIPT parameters had improved. In another study published in 2015, Cunningham et al (11) randomly allocated patients who had been admitted to either a standard pulse oximeter or one that had been altered to read 4% percentage points higher. The group who had artificially altered Sp0 2 had less supplemental oxygen prescribed, fewer adverse events and ICU admissions, and a
IP
T
hospital LOS. This study was prompted by a discrepancy in recommendations for supplemental
CR
oxygen therapy between UK and US guidelines; the UK guideline suggested 94% while recommendations from the AAP suggested 90%. (9) In the most recent update of the UK
US
guideline, 92% is now recommended.(12)
It is not surprising that with no agreement on a recommendation for what constitutes
AN
hypoxia necessitating supplemental oxygen, and a lack of evidence that outcomes are improved
M
with more supplemental oxygen, that is there is such substantial variation in management.
ED
Another management strategy that has been investigated is whether continuous SpO2 measurement vs intermittent measurement has any impact on outcomes. In 2015, McCulloh et
PT
al published data from a series of hospitalized patients comparing intermittent versus
CE
continuous pulse oximetry, and found no change in adverse events or LOS.(13)
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HOME OXYGEN THERAPY
Management of supplemental oxygen as a potential out-of-hospital therapy has emerged as one strategy aimed at improving the treatment, disposition, and inpatient LOS of patients with bronchiolitis and hypoxemia. The first description of home oxygen therapy (HOT) being used on discharge from an emergency department (ED) in the US was in 2006 when Bajaj et al published a trial of patients of 37 patients who successfully completed a predetermined
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ACCEPTED MANUSCRIPT observation of 8 hours.(14) One patient returned and had an uncomplicated hospital course. This was the first description of the feasibility of HOT for bronchiolitis for children discharged from an ED setting. It was part of randomized trial of patients who were treated with traditional inpatient admission for supplemental oxygen. This group of investigators went on to institute a
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treatment pathway for home oxygen from the ED. (Figure 1) The pathway set the SpO2
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threshold at less than 88%. In 2012, Halstead et al published a retrospective study of this pathway, including nearly 4200 ED bronchiolitis visits, with 649 children discharged on
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supplemental oxygen, and reported on disposition and outcomes for these patients.(15) They found ED discharge on HOT safely reduced the hospitalization rate for these patients from 40 to
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31%. There was no difference in return visits between patients discharged on RA versus those
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sent home on oxygen. It is important to note that this institution is located at an elevation of
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1600 m (5280 ft), and that discharge home from the inpatient units on HOT was already a common practice at this institution. .
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The start of a program to discharge infants after a 24-hour observation period has also
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been described along with an analysis of the barriers to success. In 2010, Sandweiss et al published data from a survey of physicians at their institution inquiring what the perceived
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barriers were to discharge.(16) “Hypoxia” was the primary barrier reported most frequently, and was also a common co-factor when other barriers were identified, such as need for deep nasal suctioning. This group then published a related survey of general pediatricians in 2012, founding that most of those with experience caring patients on HOT post discharge lived at higher altitudes, and most found it difficult to decide when to stop the supplemental oxygen.(17) In 2013, Sandweiss et al published results from the implementation of a HOT
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ACCEPTED MANUSCRIPT protocol that resulted in an increase in admitted children discharged within 24 hours from 20.0 to 38.4%.(18) Concern about the safety of HOT has been described as a barrier to its use. However, when pooled, the four published studies of ED discharge on HOT have demonstrated a low rate
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of return and admission (4.9-9.4%) This is similar to the rate of return visits and admission for
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patients with bronchiolitis who were discharged on room air. There was also a low rate of adverse events with HOT. Only 1 out of 1145 home oxygen patients subsequently required
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mechanical ventilation.(14,15,19,20) (Table 1) ED discharge on HOT has also been associated with high levels of caregiver comfort and satisfaction, with 88% of caregivers preferring home
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oxygen to hospitalization.(14,20) However, all published studies of ED discharge on HOT for
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bronchiolitis have been performed at relatively high altitude (over 5200 ft or 1585 m) and
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current use remains primarily limited to these geographic areas. However, in 2009, Tie et al described patients in Australia that were discharged on HOT after 24 hours of inpatient
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care.(21) This study included home nursing visits, and referred to the home setting as “hospital
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in the home.” This same center then published results from a program they created called “Hospital in the Home Oxygen (HiTHOx) Program.”(22) This program looked at patients who
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completed a 12-hour period in the hospital prior to being discharged. One hundred and twelve patients were enrolled and the return rate was 6% with no adverse outcomes. As mentioned above, the literature for HOT from the ED is primarily from high altitude metropolitan locations, and this has raised concerns about implementing a system at lower altitudes. One of the foremost criticisms has historically been the unclear correlation between disease severity, degree of hypoxemia, and altitude. The American Academy of Pediatrics’
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ACCEPTED MANUSCRIPT clinical practice guideline for the diagnosis, management and prevention of bronchiolitis, suggested the use of a pulse oximetry (SpO2) value of 90% as a threshold for initiation of supplemental oxygen and a 2015 survey of pediatric emergency medicine physicians showed a relative national consensus on this threshold.(9, 23) While current use of HOT at ED discharge
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remains low at sea-level locales, most (85%) providers recognized it as safe in the 2015 survey.
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Fifty-four percent felt it would be feasible at their institution, but readiness for implementation was poor. Major barriers to implementation noted in the survey included: lack of support, lack
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of home health agencies equipped to provide outpatient oxygen to pediatric patients, lack of
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ED observation space, difficulty arranging home oxygen, and caregiver education concerns.(23)
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HYPOXIA AND OUTCOMES
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Most providers understand that the evaluation of the infant with bronchiolitis in the ED is limited and that and we are likely catching episodes of hypoxia that are occurring normally
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outside of the care setting. In fact, some oxygen desaturations are likely normal (healthy infants
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have desaturations during sleep.(24) Some studies have shown lower mortality when oxygen saturations are maintained above 90% in premature infants,(25) and neurodevelopmental
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delays with mild desaturations in children with congenital heart disease,(26) or those living at high altitude.(27) However, these findings cannot necessarily be extrapolated to otherwise healthy infants whose temporary hypoxia is caused by a transient, acute respiratory illness. Additionally, mild hypoxemia associated with asthma, which may be more similar in its transient nature to the hypoxemia associated with bronchiolitis, has not been shown to lead to any long term neurocognitive deficits.(28) However, other studies of children with asthma have
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ACCEPTED MANUSCRIPT suggested an association between hypoxemia and behavioral problems.(26) Recently, a compelling study by Principi et al followed well-appearing infants with bronchiolitis who were not hypoxic at their ED visit and were discharged home on room air.(29) Many of these patients had SpO2 desaturations at home with many of these described as significant (greater
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than 1 minute at SpO2 <70% or greater than 3 minutes at SpO2 <90%). Ten percent of subjects
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spent more than 10% of the time with a SpO2 less than 90%). In this study the rate of unscheduled return visits and hospitalization was similar for both hypoxic and non-hypoxic
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infants. This data combined with clinical experience with these patients suggests we may be overtreating what are likely expected episodes of transient hypoxia that may not have any
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QUALITY IMPROVEMENT EFFORTS
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untoward effects.
In 2013, the Choosing Wisely Campaign came forth with a recommendation to not use
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continuous pulse oximetry routinely in children with acute respiratory illness unless they are on
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supplemental oxygen.(30) Despite the fact that quality improvement efforts to improve care of children with acute respiratory illnesses have been increasing in recent years, published reports
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of projects addressing the utilization of pulse oximetry are limited. In 2015, Schondelmeyer et al published their results from a QI intervention to decrease the use of continuous pulse oximetry.(31) While they did show a reduction in use from 10 hours to 3 hours, there was no associated change in LOS. The authors noted that there was still a significant impact from this work in terms of reducing alarm fatigue.
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ACCEPTED MANUSCRIPT SUMMARY AND THOUGHTS FOR THE FUTURE The practice utilizing pulse oximetry as a tool to determine disposition in patients with bronchiolitis is likely leading to over-diagnosis of hypoxemia, over treatment, unnecessary hospitalization, and increased cost.(32) The significance of transient hypoxemia remains
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unclear. There is no consensus definition of transient, nor is there consensus on how low is too
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low, leading to a lack of evidence-based parameters for the use of pulse oximetry in the setting of acute respiratory illness. The AAP guidelines suggest that physicians may choose not to
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administer supplemental oxygen for saturations greater than 90%, and may choose not to use continuous pulse oximetry for infants with bronchiolitis, with a “weak” recommendation.
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Research and quality improvement efforts are needed to expand the evidence base to support
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these or different recommendations. As the routine use of pulse oximetry seems difficult to
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reduce, it may be useful to begin to try to use the Sp02 as just one factor amongst the entire clinical picture to make more data-driven decisions. Because so many children are admitted and
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stay in the hospital, home oxygen therapy remains a practical and safe alternative to
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hospitalization; and needs further evaluation including centers at sea level altitudes.
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ACCEPTED MANUSCRIPT References 1.
Centers for Disease Control and Prevention. Respiratory syncytial virus infection: trends and surveillance 2017. Avsailable at: https://www.cdc.gov/rsv/research/ussurveillance.html - f1. Accessed February 3rd, 2018, 2018.
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Shay DK, Holman RC, Newman RD, et al. Bronchiolitis-associated hospitalizations among
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Mallory MD, Shay DK, Garrett J, Bordley WC. Bronchiolitis management preferences and
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the influence of pulse oximetry and respiratory rate on the decision to admit. Pediatrics 2003;111(1):e45-51.
Unger S, Cunningham S. Effect of oxygen supplementation on length of stay for infants
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Schuh S, Freedman S, Coates A, et al. Effect of oximetry on hospitalization in
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hospitalized with acute viral bronchiolitis. Pediatrics 2008;121(3):470-475.
bronchiolitis: a randomized clinical trial. JAMA 2014;312(7):712-718. Doucette A, Jiang X, Fryzek J, et al. Trends in respiratory syncytial virus and bronchiolitis
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hospitalization rates in high-risk infants in a United States nationally representative database, 1997-2012. PloS One 2016;11(4):e0152208. Hasegawa K, Tsugawa Y, Brown DF, et al. Temporal trends in emergency department
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visits for bronchiolitis in the United States, 2006 to 2010. Pediatr Infects Dis J 2014;33(1):11-18. 8.
American Academy of Pediatrics Subcommittee on Diagnosis and Management of Bronchiolitis. Diagnosis and management of bronchiolitis. Pediatrics 2006;118(4):17741793.
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Ralston SL, Lieberthal AS, Meissner HC, et al. Clinical practice guideline: the diagnosis, management, and prevention of bronchiolitis. Pediatrics 2014;134(5):e1474-1502.
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Hendaus MA, Jomha FA, Alhammadi AH. Pulse oximetry in bronchiolitis: is it needed? Ther Clin Risk Manag 2015;11:1573-1578.
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Cunningham S, Rodriguez A, Adams T, et al. Oxygen saturation targets in infants with
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bronchiolitis (BIDS): a double-blind, randomised, equivalence trial. Lancet 2015;386(9998):1041-1048.
Ricci V, Delgado Nunes V, Murphy MS, Cunningham S. Bronchiolitis in children: summary
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of NICE guidance. BMJ (Clinical research ed) 2015;350:h2305. McCulloh R, Koster M, Ralston S, et al. Use of intermittent vs continuous pulse oximetry
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13.
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for nonhypoxemic infants and young children hospitalized for bronchiolitis: a
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randomized clinical trial. JAMA Pediatr 2015;169(10):898-904. Bajaj L, Turner CG, Bothner J. A randomized trial of home oxygen therapy from the
Halstead S, Roosevelt G, Deakyne S, Bajaj L. Discharged on supplemental oxygen from an
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emergency department for acute bronchiolitis. Pediatrics 2006;117(3):633-640.
emergency department in patients with bronchiolitis. Pediatrics 2012;129(3):e605-610. Sandweiss DR, Corneli HM, Kadish HA. Barriers to discharge from a 24-hour observation
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unit for children with bronchiolitis. Pediatr Emerg Care 2010;26(12):892-896. 17.
Sandweiss DR, Kadish HA, Campbell KA. Outpatient management of patients with bronchiolitis discharged home on oxygen: a survey of general pediatricians. Clin Pediatr. 2012;51(5):442-446.
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Sandweiss DR, Mundorff MB, Hill T, et al. Decreasing hospital length of stay for bronchiolitis by using an observation unit and home oxygen therapy. JAMA Pediatr 2013;167(5):422-428.
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Flett KB, Breslin K, Braun PA, Hambidge SJ. Outpatient course and complications
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associated with home oxygen therapy for mild bronchiolitis. Pediatrics 2014;133(5):769-
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Freeman JF, Deakyne S, Bajaj L. Emergency department-initiated home oxygen for
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bronchiolitis: a prospective study of community follow-up, caregiver satisfaction, and outcomes. Acad Emerg Med 2017;24(8):920-929
Tie SW, Hall GL, Peter S, et al. Home oxygen for children with acute bronchiolitis. Arch
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21.
Zappia T, Peter S, Hall G, et al. Home oxygen therapy for infants and young children with
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Dis Child 2009;94(8):641-643.
acute bronchiolitis and other lower respiratory tract infections: the HiTHOx program.
Freeman JF, Brou L, Mistry R. Feasibility and capacity for widespread use of emergency
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Issues Compr Pediatr Nurs 2013;36(4):309-318.
department-based home oxygen for Bronchiolitis. Am J Emerg Med 2017;35(9):1379-
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Hunt CE, Corwin MJ, Lister G, et al. Longitudinal assessment of hemoglobin oxygen saturation in healthy infants during the first 6 months of age. Collaborative Home Infant Monitoring Evaluation (CHIME) Study Group. J Pediatr 1999;135(5):580-586.
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Stenson BJ, Tarnow-Mordi WO, Darlow BA, et al. Oxygen saturation and outcomes in preterm infants. NEJM 2013;368(22):2094-2104.
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Bass JL, Corwin M, Gozal D, et al. The effect of chronic or intermittent hypoxia on cognition in childhood: a review of the evidence. Pediatrics 2004;114(3):805-816.
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Wehby GL. Living on higher ground reduces child neurodevelopment-evidence from South America. J Ppediatr 2013;162(3):606-611.e601.
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Rietveld S, Colland VT. The impact of severe asthma on school children. J Asthma
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28.
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1999;36(5):409-417.
Principi T, Coates AL, Parkin PC, et al. Effect of oxygen desaturations on subsequent
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medical visits in infants discharged from the emergency department with bronchiolitis. JAMA Pediatr 2016;170(6):602-608.
Quinonez RA, Garber MD, Schroeder AR, et al. Choosing wisely in pediatric hospital
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30.
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medicine: five opportunities for improved healthcare value. J Hosp Med 2013;8(9):479-
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Schondelmeyer AC, Simmons JM, Statile AM, et al. Using quality improvement to reduce
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continuous pulse oximetry use in children with wheezing. Pediatrics 2015;135(4):e1044-
Quinonez RA, Coon ER, Schroeder AR, Moyer VA. When technology creates uncertainty: pulse oximetry and overdiagnosis of hypoxaemia in bronchiolitis. BMJ 2017;358:j3850.
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32.
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1051.
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ACCEPTED MANUSCRIPT Table 1. Review of patients discharged on home oxygen therapy from published studies.
Site of Observation Intubated (n)
Length of Observation
Oxygen Limit
Bajaj, 2006 2.7
37
2-24 months 0
ED
8 hours
1 L/min
Tie, 2009 4.5
22
3-24 months 0
Hospital
24 hours
1 l/min
Halstead, 2012 6
649
3-18 months 0
ED
8 hours
Zappia, 2013 6
112
> 2 months 0
Hospital
Fleet, 2014 9.4
253
2-24 months 0
ED
Freeman, 2017 4.9
225
3-18 months 1
ED
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N Age Inclusion Return Admission (%)
1 l/min
4 hours
1 l/min
8 hours
0.5 l/min
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12 hours
0.5 l/min
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Figure 1