Detectable Concentrations of Inhaled Tobramycin in Critically Ill Children Without Cystic Fibrosis: Should Routine Monitoring Be Recommended?

OBJECTIVES

To determine the percentage of detectable tobramycin troughs and acute kidney injury in critically ill children without cystic fibrosis on inhaled therapy.

DESIGN

Historic cohort.

SETTING

Academic hospital.

PATIENTS

Forty children less than 18 years receiving inhaled tobramycin across 6.5 years.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The primary objective was to determine the percentage of detectable tobramycin troughs greater than or equal to 0.5 µg/mL. Secondary objectives included a comparison of acute kidney injury in children with and without detectable troughs. Twenty-two (55%) had trough concentrations obtained. Ten of these (45.5%) had detectable concentrations, with a median of 0.85 µg/mL (interquartile range, 0.5-2.0). There was no statistical significance between the detectable and nondetectable groups in age, gender, and method of administration. However, patients in the detectable group tended to be younger than nondetectable group and more likely to have a tracheotomy. There was a clinically significant decrease in estimated glomerular filtration rate in the detectable trough group.

CONCLUSIONS

Detectable troughs were noted in almost half of patients with concentrations obtained. A clinically significant decrease in estimated glomerular filtration rate was noted in patients with detectable concentrations. Continued work should be directed to better understand outcomes and monitoring in children requiring inhaled tobramycin.