Evaluation of different treatment thresholds in a clinical pathway for children with acute asthma

The administration of bronchodilators for acute asthma is based on serial
assessments of the patient*s respiratory status. In daily practice, this may
result in variability and/or delay in the decision-making process to wean or
intensify bronchodilator administration. We aim to improve the quality of care
by standardizing inpatient asthma care and reduce the length of stay. Clinical
pathways for acute asthma outline a sequence for assessment and interventions.
They have reduced admission time and healthcare costs. Several asthma scores
have proven to be useful in clinical pathways. However, all asthma scores
require auscultation of the lungs to score the degree of wheezing or air entry.
Therefore, all healthcare providers should be sufficiently trained in
auscultation of the lungs before the possible implementation of such a score.
This prompted us to develop an asthma score that does not require auscultation
of the lungs. This innovative asthma score was adapted from the physical
findings in pediatric asthma scores validated previously. We recently
demonstrated that this childhood asthma score (CAS) could accurately predict
the bronchodilator nebulization requirement compared to the routine clinical
judgment of the attending physician to administer bronchodilators.
Subsequently, we conducted a study to implement a nurse-driven clinical pathway
based on our innovative asthma score.

This pathway included standardized respiratory assessments and a protocol for
the nursing staff to administer bronchodilators without a specific order from
the physician. We compared the length of stay and the number of readmissions to
a historical cohort. Patients treated according to the nurse-driven protocol
were 3.3 times more likely to be discharged earlier (hazard ratio, 3.29; 95%
confidence interval, 2.33-4.66; P < 0.05), and length of stay was significantly
reduced (median 28 versus 53 h) compared to the historical standard practice.
Patient safety was not compromised, and none of the patients were removed from
the pathway.
Although the nurse-driven clinical pathway decreased length of stay without
compromising patient safety, one major drawback was frequently reported.
Patients who need supplemental oxygen had a CAS score of at least 4, indicating
the need for bronchodilator therapy, even though it appeared that the patient
was not tachypnic nor dyspneic (eg, when the patient was asleep). This can be
explained by the fact that low oxygen saturation may result from atelectasis
and ventilation/ perfusion mismatch without small airway obstruction.
The results of our previous study encourage us to further evaluate and adapt
the pathway for patients who need supplemental oxygen. In this randomised
study, length of stay and safety for patients who need supplemental oxygen
treated according to the current pathway will be compared to a pathway with
adjusted treatment thresholds.

Evaluation of the effect of different treatment thresholds in a clinical
pathway for children with acute asthma who are treated with supplemental oxygen

A randomized non-inferiority study. We aim to demonstrate that adjustment of
the treatment threshold for children who are treated with supplemental oxygen
does not result in a longer length of stay. We consider a difference of 8 hours
as clinically relevant.

The intervention comprises adjusted treatment thresholds for patients with
acute asthma who need supplemental oxygen.
If randomised to the standard care nurse-driven pathway the treatment
thresholds will be according to current cut-off values, CAS <4, CAS 4-6, CAS
7-8 and CAS 9-12. Figure 2 page 17 protocol.

If the patient is randomised to the new pathway, patients treated with
supplemental oxygen will be treated with bronchodilators based on adjusted CAS
scores. The cut off values for the first two treatment thresholds will be CAS
<5, CAS 5-6, respectively.
Treatment thresholds will not change for moderate or severe acute asthma (CAS
7-8 en CAS 9-12).
Figure 3 page 18 protocol.

Acute asthma is one of the most common reasons for hospital admission in
childhood.
We have demonstrated that a nurse-driven clincial pathway significantly reduces
admisson time without compromising patient safety.
The results of our previous study encourage us to further evaluate and adapt
the pathway for patients who need supplemental oxygen.
Patients are treated with bronchodilators, and as needed systemic
corticosteroids, supplemental oxygen and intravenous
magnesiumsulphate.according to the current Dutch guideline for acute asthma.
For patients who need supplemental oxygen, only the treatment thresholds for
mild acute asthma will be adjusted.
Furthermore
-In case of severe asthma (score >8) the attending physician is called to
assess the patient's respiratory status
-The nurse can call the attending physician to assess the patient at their own
discretion
-Patients heartrate, respiratory rate and transcutaneous oxygen saturation are
continously monitored.
-Pediatric early warning scores are used in our department to detect
deterioration of the patient

With these precautions we expect minimal risk for the patients.