Discharged on Supplemental
Oxygen from an Emergency
Department in Patients with
Bronchiolitis.
S Halstead, G Roosevelt,
S Deakyne, L Bajaj
Pediatrics Vol 129 (3), Mar 2012.
604 - 611
presented by
Eleanor McCowen
17th Jan 2013
Plan of talk.
• Background and overview of study
• Following the CASP format:
–
–
–
–
Screening questions
Are the results of the study valid?
What are the results?
Will the results help me locally?
• Other relevent papers
CASP = Critical Appraisal Skills Programme
Background
• Bronchiolitis most common reason for US hospital
admission in < 12mo
• Admission rates for Bronchiolitis increasing
(>150 000 p.a. in USA) though outcomes unchanged.
• Considerable variability in management policies
• Small changes in O2 sats cut-off values large
differences in admission rates
• O2 therapy often persists after other parameters
normalised.
• Several previous studies: What O2 cut-off is safe for
discharge?
Background cont’d
• Denver Colorado tertiary paediatric ED
• In 2005 they introduced a home O2 protocol
- for uncomplicated bronchiolitis with hypoxia
• This is their evaluation of whether the protocol reduced
admission rates safely
Denver Colorado (1600m
elevation)
Methods
• Denver PED(Paediatric Emergency Dept) + 4 satellite
PEDs
• Retrospective notes review
• Four years: 2005 - 2009
• Included: All children 1- 18 mo diagnosed with
Bronchiolitis between Nov + April
• Excluded: if pre-existing oxygen therapy
• 4,194 illnesses studied
• Also costed ave hospital stay, and Home O2 alternative
Methods (cont’d)
They recorded basic and demographic data, and which
patients had:
• Initial Admission/ transfer
• Discharge on Room Air (RA)
– And how many readmitted
• Discharge on Home Oxygen
– And how many readmitted
Of home O2 readmissions, recorded:
• Reason for readmission
• Adverse airway outcomes (ICU, NIV, intubation)
Home O2Protocol
Patient must be:
• 3 – 18 mo age (min 48/40 corrected age)
• No chronic cardiopulmonary disease
• Observed for >8 hrs with 2 hrly obs + continuous SaO2.
• Have SaO2 ≥90% sleeping, feeding and awake
• Be in ≤ 0.5 L/min oxygen
• Feeding adequately
• No evidence of respiratory deterioration
Home O2Protocol (cont’d)
Then if doctor and parent comfortable with Home O2
discharge:
 Discharged on home O2 after parent training
 24hr F/U appointment arranged with PCP* or in PED
PCP = Primary care provider, i.e. Office Paediatrician or GP
Statistics
• Categorical variables: used x2 or Fischer exact tests
• Continuous variables: used Student t or Wilcoxon rank sum
tests
Results
Results
4194 illnesses
649 (15%) initially
discharged on O2
38 (6%) admitted
subsequent visit*
(95%CI: 4.3 0 7.9%)
2383 (57%) initially
discharged on RA
1162 (28%) initially
admitted to hospital
90 (4%) admitted
subsequent visit*
(95%CI: 3.1 – 4.6%)
*P = 0.03
RA = room air
TABLE 1 Demographic Characteristics of Study
Population
Overall
D/C on RA D/C on RA D/C on O2 D/C on O2
(Not
Admitted)
Then
Admitted
(Not
Admitted)
Then
Admitted
Admit
Illnesses, n
(%)
4194
2293 (55)
90 (2)
611 (15)
38 (0.9)
11562 (28)
Mean age,
mo (SD)
7.6 (4.8)
7.8 (4.4) a
6.0 (5.0) a
8.9 (4.4) b
7.2 (3.8) b
6.3 (5.1)
Male
patient (%)
2497 (59)
1371 (60)
63 (70)
364 (60)
28 (74)
671 (58)
Medicaid
(%)
2348 (56)
1340 (58)
54 (60)
319 (52)
22 (58)
613 (55)
D/C, discharged from hospital.
a P < .01: D/C home on RA (not admitted) versus D/C home on RA then admitted.
b P = .03: D/C home on O2 (not admitted) versus D/C home on O2 then admitted.
Table 2
Page 606
• For those readmitted after discharge in air (vs those who
were not readmitted), initial temp, RR, HR and use of
epinephrine were higher.
• For those sent home on oxygen then readmitted (vs not
readmitted), no difference in clinical characteristics,
including mean lowest SaO2 in room air.
TABLE 3 Reasons for Subsequent
Admission
for Patients Discharged From Hospital on
Oxygen
Reason
a
n = 39
Increased O2
19 (59%)
Increased work of breathing
17 (44%)
Parental concern/compliance
10 (62%)
Intravenous fluids for poor oral intake
4 (18%)
Problem with home O2
2 (10%)
a Patients may have more than 1 reason for subsequent admission.
Other results
• None of those readmitted on home oxygen required
advanced airway management.
• Thirty-five patients under 3 month who were discharged
on O2 included (3 readmitted).
• Two readmissions for unrelated reasons (not
bronchiolitis) not included in readmission data.
• Mean length for stay for home O2 patients 10 hours.
Conclusions
• “First study demonstrating that home oxygen protocol for
selected patients [..]can be successful and sustainable.”
• Admission rates 40% historically, to 31% now.
• More patients (6% vs 4%) were readmitted in the home O2
discharge group than the D/C in room air group.
• Discuss costs (about half for home O2 vs admit) though
continuing care beyond first F/U not included
Conclusions (cont’d)
• Apnoea: important concern. Prev study (691 pts, 19 had
apnoea), those who had apnoeas were: < 1 mo, ex-preterm
and <48/40 CGA, or had an apnoea witnessed at home.
Home O2 protocol excludes all the above.
• No readmitted patients “had apnoea requiring advanced
airway management” (any had apnoea though?)
• Readmission to non-network site would not be recorded
(though they think they would know about any deaths!)
• Altitude – increased familiarity with home O2
- what would their patients’ SaO2 be at sea level?
CASP Screening
questions
1. Did the study address a clearly focused
issue?
Yes : Is home oxygen a safe way to lower admission rates
for Bronchiolitis in their hospital? They asked:
• Qu 1 Were admission rates lowered?
• Qu 2 Were adverse outcomes increased?
2. Did the authors use an appropriate
method to answer their question?
Yes, Retrospective Comparative study acceptable.
Randomised Prospective study would have allowed them
to collect more information, eg more detail on
undesirable outcomes, comparison of length of stay.
Are the results of the
study valid?
4. Was the exposure accurately
measured to minimize bias? Yes
• ‘Exposure’ group clearly defined.
• Recruitment to exposure group followed clear protocol.
• The exceptions detailed (eg 1- 3 mo babies) didn’t follow
the protocol but this should not skew their data, as 1 – 3
mo babies included in the study.
5. Was the outcome accurately measured to
minimize bias?
• All objective measures eg admission rates, ICU, NIV,
etc.
So yes, but…
• Other potential adverse effects not examined
– eg. feeding difficulties, infective complications, carer anxiety,
availability and quality of community support.
6. Have the authors identified all important
confounding factors?
• Readmissions to non-network facilities: Cannot tell how
significant this effect is. Possible that those unhappy with
initial Rx more likely to go elsewhere.
• Would want more information on who provides
community care and the work load created.
7. A. Was the follow up of subjects complete
and long enough?
Yes – Would not expect any delayed adverse effects.
What are the results?
8. Bottom line results?
• They reduced admission rates and none of the children
sent home on oxygen came back needing airway
intervention
10. Do you believe the results?
• Convincingly large numbers: 649 children sent home on
home O2
Will the results help me
locally?
11. Can the results be applied to the local
population?
• Generalisable: Included all patients 1 -18 mo with
bronchiolitis (unless already on home oxygen).
• BUT.. because of their altitude, with the same sats, our
patients likely to be sicker.
…and to our local setting?
• Hospital: medical and nursing assessment, training for
home O2
• Community facilities: community nursing (or GPs??),
follow up appt, weaning.
• Oxygen supplies,
• Parents: No demographic data, but s.e. status and
parental education likely to be an important factor. How
important are the cultural differences between here and
America, eg in acceptance of Rx?
12. Do the results of this study fit with other
available evidence?
• Yes - admission rates, ave. length of stay, percentage of
children eligible for home oxygen.
What’s good about this paper?
• Simple
• Good numbers of patients
• Interesting new take on an old problem
What’s not good?
• Brushed over the community follow up a bit
• Could have covered other adverse outcomes, including
history of apnoea.
Any comments?
(Some other relevant papers to follow)
Other relevant papers: 1
‘Outpatient management of patients with bronchiolitis
discharged home on oxygen: a survey of general
paediatricians’ (Utah)
Sandweiss DR , Kadish HA , Campbell KA
Clin Pediatr (Phila) May 2012; Vol 51 ( 5 ) P 442-6
“Pediatricians are not routinely managing home oxygen for
hypoxic bronchiolitis patients. Variable weaning process,
difficulties in determining oxygen stoppage, multiple
follow-up visits, and prolonged home oxygen usage
highlight the need to evaluate the impact of this
emerging practice.”
Other relevant papers: 2
‘Impact of home oxygen therapy on hospital stay for infants
with acute bronchiolitis.’
Gauthier M , Vincent M , Morneau S , Chevalier I
Eur. J. Pediatr. Dec 2012; Vol 171 (12 ) 1839-1844
University of Montreal, Canada. Looked at sending home
on O2 after 24 hours.
“7.1 % of patients, a mean of 1.8 days prior to real
discharge[…] The number of patient-days of
hospitalization which would have been saved would be
3.0 % of total in-patient-days[…] not significantly
decrease the overall burden of hospitalization for
bronchiolitis.”
Other relevant papers: 3
‘Home oxygen for children with acute bronchiolitis.’
Tie SW , Hall GL , Peter S et al
Arch. Dis. Child. Aug 2009; Vol 94 (8 ) 641-3
Perth, Australia.
D/C after 24 hrs. Randomised to home oxygen or inpatient
care. Reduced hospital stay by 2 days.
Discussion
Thankyou