A survey of once-daily dosage tobramycin therapy in patients with cystic fibrosis.

The purpose of this study was to quantify the prevalence of once-daily dosage of tobramycin (ODDT) among Cystic Fibrosis Foundation-accredited care centers and affiliated programs (CFFACCs) and characterize the ODDT approaches used by these institutions. An anonymous cross-sectional survey of CFFACCs was performed using an electronic survey tool. This tool was electronically mailed to the program directors. Eighty-four out of 195 institutions completed the survey (response rate = 43%). Fifty-one (61%) of 84 centers reported using ODDT. Of those 51 institutions, 34 (67%) use a dosage of 10 mg/kg/dose. Serum creatinine was measured routinely in 51 centers (100%) with weekly monitoring being used in 40 centers (78%). Audiometric evaluation was performed routinely in 22 (43%) centers with annual assessment performed in 14 (64%) of these 22 centers. In conclusion, a majority of responding institutions use ODDT. The most common reported dosage is 10 mg/kg. Serum creatinine was routinely measured in all institutions with weekly assessment being the most common frequency. Audiometic assessment is routinely performed in <50% of centers. Of the institutions performing audiograms routinely, annual assessment is the most common frequency.