Table 2.

Piperacillin/tazobactam content during storage in Easypump II (B. Braun) elastomeric devices as determined using a stability indicating HPLC assay

Timepoint	90 mg/mL*		25 mg/mL†
	PIP+TAZ, % remaining	95% CI (%)	PIP+TAZ, % remaining	95% CI (%)
Day 0	100.0 (87.3±0.7 mg/mL)	99.2 to 100.8	100 (24.6±0.5 mg/mL)	97.9 to 102.1
Day 7	101.7	101.6 to 101.8	100.8	100.42 to 101.18
Day 11	101.1	99.83 to 102.37	102.2	102.13 to 102.27
Day 13	100.7	100.6 to 100.8	98.9	97.35 to 100.45
Day 13+1	100.8	100.22 to 101.38	101.0	100.91 to 101.09

*90 mg/ml total drug concentration: 80 mg piperacillin/10 mg tazobactam.

†25 mg/ml total drug concentration: 22 mg piperacillin/3 mg tazobactam.

PIP, piperacillin; TAZ, tazobactam.