Adjunctive Pharmacotherapies in Children With Asthma Exacerbations Requiring Continuous Albuterol Therapy: Findings From The Ohio Pediatric Asthma Repository

Wide Institutional Variability in the Treatment of Pediatric Critical Asthma: A Multicenter Retrospective Study

OBJECTIVES

Children with status asthmaticus refractory to first-line therapies of systemic corticosteroids and inhaled beta-agonists often receive additional treatments. Because there are no national guidelines on the use of asthma therapies in the PICU, we sought to evaluate institutional variability in the use of adjunctive asthma treatments and associations with length of stay (LOS) and PICU use.

DESIGN

Multicenter retrospective cohort study.

SETTING

Administrative data from the Pediatric Health Information Systems (PHIS) database.

PATIENTS

All inpatients 2-18 years old were admitted to a PHIS hospital between 2013 and 2021 with a diagnostic code for asthma.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

This study included 213,506 inpatient encounters for asthma, of which 29,026 patient encounters included care in a PICU from 39 institutions. Among these PICU encounters, large variability was seen across institutions in both the number of adjunctive asthma therapies used per encounter (min: 0.6, median: 1.7, max: 2.5, p < 0.01) and types of adjunctive asthma therapies (aminophylline, ipratropium, magnesium, epinephrine, and terbutaline) used. The center-level median hospital LOS ranged from 1 (interquartile range [IQR]: 1, 3) to 4 (3, 6) days. Among all the 213,506 inpatient encounters for asthma, the range of asthma admissions that resulted in PICU admission varied between centers from 5.2% to 47.3%. The average number of adjunctive therapies used per institution was not significantly associated with hospital LOS ( p = 0.81) nor the percentage of encounters with PICU admission ( p = 0.47).

CONCLUSIONS

Use of adjunctive therapies for status asthmaticus varies widely among large children's hospitals and was not associated with hospital LOS or the percentage of encounters with PICU admission. Wide variance presents an opportunity for standardizing care with evidence-based guidelines to optimize outcomes and decrease adverse treatment effects and hospital costs.

Human microvascular reactivity: a review of vasomodulating stimuli and non-invasive imaging assessment

The microvasculature serves an imperative function in regulating perfusion and nutrient exchange throughout the body, adaptively altering blood flow to preserve hemodynamic and metabolic homeostasis. Its normal functioning is vital to tissue health, whereas its dysfunction is present in many chronic conditions, including diabetes, heart disease, and cognitive decline. As microvascular dysfunction often appears early in disease progression, its detection can offer early diagnostic information. To detect microvascular dysfunction, one uses imaging to probe the microvasculature's ability to react to a stimulus, also known as microvascular reactivity (MVR). An assessment of MVR requires an integrated understanding of vascular physiology, techniques for stimulating reactivity, and available imaging methods to capture the dynamic response. Practical considerations, including compatibility between the selected stimulus and imaging approach, likewise require attention. In this review, we provide a comprehensive foundation necessary for informed imaging of MVR, with a particular focus on the challenging endeavor of assessing microvascular function in deep tissues.

Randomized pilot trial of ipratropium versus placebo in children with critical asthma

OBJECTIVE

To test the effects of inhaled ipratropium on clinical outcomes of critical asthma in the first randomized trial of this adjunctive therapy in critically ill children.

DESIGN

Pilot, placebo-controlled, double-blinded, and randomized-controlled trial PATIENTS: Thirty children (15 per group) with critical asthma receiving high-intensity albuterol per a standardized pathway utilizing objective assessments to wean patients to less frequent albuterol administration.

INTERVENTIONS

Subjects were randomized to receive either nebulized ipratropium bromide (500 µg in 0.9% saline per dose) or an equivalent volume of nebulized 0.9% saline every 6 h until the patient was successfully weaned to albuterol doses every 2 h ("q2 albuterol").

MEASUREMENTS AND MAIN RESULTS

Demographics, initial clinical severity score, and asthma histories were similar between groups. There was no significant difference in the median duration of high-intensity albuterol between the treatment group (17.5 [10.3-22.1] h) and placebo group (14.6 [12.7-24.5] days; p = .56). Similarly, there was no significant difference in pediatric intensive care unit length of stay (22.6 [21.1-33.6] vs. 21.4 [16.1-35.8] h; p = .74) or hospital length of stay (48.0 [41.8-59.8] vs. 47.3 [37.2-63.1] h; p = .67). In multivariate linear regression adjusting for identified confounders, treatment with ipratropium was not significantly associated with any of the three outcomes. Side effects were rare and occurred with equally between both groups CONCLUSIONS: Adjunctive therapy with ipratropium was not associated with decreased duration of high-intensity albuterol or shortened length of stay when compared to placebo. A larger, multicenter trial is warranted to confirm that ipratropium does not improve clinical outcomes.

Quantifying continuous nebulization via high flow nasal cannula and large volume nebulizer in a pediatric model

BACKGROUND

Use of high flow nasal cannula (HFNC) to deliver aerosolized medications to children has gained considerable interest. However, data on continuous albuterol delivery (CAD) via HFNC are lacking. This study quantified CAD via HFNC/vibrating mesh nebulizer (VMN) and large-volume jet nebulizer (LVN) with face mask (FM) in a pediatric model. Aerosol delivery with two HFNC cannula designs were also compared.

METHODS

A pediatric manikin was connected to a lung simulator (Vt = 150 mL, RR = 28 breaths/minute, I:E 1:2.4) via collecting filter at the carina. XL Pediatric and SML Adult HFNC designs were tested to determine optimal cannula design for CAD. VMN was placed Before humidifier (37°C), albuterol (5 mg/mL) was nebulized at 3, 6, and 12 L/minute (n = 3). To compare HFNC/VMN with LVN and FM, albuterol (15 mg/hour) was aerosolized for 3 hours/device (n = 3). LVN was connected to FM and filled with 9 mL of albuterol (5 mg/mL) and 66 mL of normal saline to deliver 25 mL/hour at 13 L/minute. VMN was connected to the infusion pump to deliver 7.5 mL/hr of albuterol (2 mg/mL). Drug eluted from filters was assayed with UV spectrophotometry (276 nm).

RESULTS

Optimal aerosol delivery occurred at 3 L/minute (12.6% ± 0.5%) with SML Adult HFNC (P = .04). When used for CAD, inhaled drug delivery with HFNC/VMN (2.2 mg/hr ± 0.1, 14.8% ± 0.7%) was significantly greater than LVN and FM (0.48 ± 0.09 mg/hour, 3.2% ± 0.6%) (P = .001).

CONCLUSIONS

Administration of CAD via HFNC/VMN led to a greater than fourfold increase in drug delivery compared to LVN with FM. Optimal aerosol delivery occurred at 3 L/minute with SML Adult HFNC.

Prehospital management of pediatric asthma patients in a large emergency medical services system

BACKGROUND

Asthma is a common pediatric diagnosis for emergency medical services (EMS) transports, however there is a paucity of data on prehospital asthma management. The purpose of this study was to describe prehospital management of pediatric patients with suspected asthma exacerbation.

METHODS

We conducted a retrospective review of electronic medical records from 24 ground EMS agencies in Southwestern Pennsylvania between 1 January 2014 to 31 December 2017. We identified patients 2 to 17 years with documented wheezing, excluding those with suspected anaphylaxis. Patients with documented respiratory distress were classified as severe asthma. We report descriptive statistics of demographics, vital signs, and management including administration of medications and performance of procedures.

RESULTS

Of 19 246 pediatric transports, 1078 (5.6%) patients had wheezing. Of these, 532 (49%) met criteria for severe asthma. Patients with severe asthma were more likely to be adolescents compared to those with nonsevere asthma (49.6% vs 6%; P < .001). While rates of intravenous methylprednisolone administration were higher in patients with severe asthma (68/532, 12.8%) compared to those with nonsevere asthma (13/546, 2.4%; P < .001), overall use of steroids was low (7.5%). Other therapies provided included albuterol (n = 699, 64.8%), ipratropium bromide (n = 271, 25.1%), and oxygen (n = 280, 26.0%). One hundred eighty patients (16.7%) received a peripheral IV line. Two patients (0.4%) were given continuous positive airway pressure.

CONCLUSION

Approximately 6% of pediatric EMS transports are for asthma. Steroid usage was low in even those with severe asthma, representing an area of process improvement. These data provide a baseline to future research to identify interventions that may improve outcomes.

Development of an Antibiotic Guideline for Children With Suspected Ventilator-Associated Infections

OBJECTIVES

To develop a guideline for the decision to continue or stop antibiotics at 48-72 hours after their initiation in children with suspected ventilator-associated infection.

DESIGN

Prospective, multicenter observational data collection and subsequent development of an antibiotic guideline.

SETTING

Twenty-two PICUs.

PATIENTS

Children less than 3 years old receiving mechanical ventilation who underwent clinical testing and initiation of antibiotics for suspected ventilator-associated infection.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Phase 1 was a prospective data collection in 281 invasively ventilated children with suspected ventilator-associated infection. The median age was 8 months (interquartile range, 4-16 mo) and 75% had at least one comorbidity. Phase 2 was development of the guideline scoring system by an expert panel employing consensus conferences, literature search, discussions with institutional colleagues, and refinement using phase 1 data. Guideline scores were then applied retrospectively to the phase 1 data. Higher scores correlated with duration of antibiotics (p < 0.001) and higher PEdiatric Logistic Organ Dysfunction 2 scores (p < 0.001) but not mortality, PICU-free days or ventilator-free days. Considering safety and outcomes based on the phase 1 data and aiming for a 25% reduction in antibiotic use, the panel recommended stopping antibiotics at 48-72 hours for guideline scores less than or equal to 2, continuing antibiotics for scores greater than or equal to 6, and offered no recommendation for scores 3, 4, and 5. The acceptability and effect of these recommendations on antibiotic use and outcomes will be prospectively tested in phase 3 of the study.

CONCLUSIONS

We developed a scoring system with recommendations to guide the decision to stop or continue antibiotics at 48-72 hours in children with suspected ventilator-associated infection. The safety and efficacy of the recommendations will be prospectively tested in the planned phase 3 of the study.

The effectiveness of magnesium sulfate for status asthmaticus outside the intensive care setting

AIM

Magnesium is an adjunctive therapy used in patients with status asthmaticus who do not respond to conventional therapy. The optimal time from initiation of therapy, to determination of response and administration of magnesium has not yet been resolved. Our objective was to determine if magnesium administered in the non-intensive care setting can decrease duration of continuous albuterol and hospital length of stay.

METHODS

We performed a retrospective cohort analysis of children ages 2-18 years admitted to the pediatric unit on continuous albuterol between January 2014 and December 2015 in a tertiary care children's hospital. Cohorts were matched on respiratory assessment score (RAS) obtained at a similar duration of albuterol therapy and evaluated for the total duration of continuous albuterol, length of stay (LOS), and adverse events.

RESULTS

Thirty-three patients who received magnesium were matched to 33 patients with the same RAS at a similar duration of continuous albuterol therapy who did not receive magnesium. Those who received magnesium had longer duration on continuous albuterol (34 vs 18 h; P = 0.001; 95% confidence interval [CI] 4-20; effect size 0.41) and longer LOS (72 vs 49 h; P = 0.037; 95% confidence interval [CI] 1-33; effect size 0.26) than those who did not receive magnesium.

CONCLUSION

Children requiring continuous albuterol for status asthmaticus can be administered magnesium sulfate outside the PICU with a low incidence of adverse events; however, among a RAS matched cohort, those who received magnesium did not experience shorter time on continuous albuterol, or hospital length of stay.