All parenteral delivery systems require a device/tissue site interface, where design, human factors, and tissue biomechanics impact successful function for consistent, reliable delivery. Limited published data exists quantifying these factors and their interaction effects on delivery success. This in vivo study examines pen needle (PN) hub design and skin application force impacts on needle penetration depth (NPD).

PN injections (2µl contrast agent) were administered to Yorkshire swine flanks at clinically measured skin application forces (0.25, 0.75, 1.25 and 2.0 lbf). In vivo NPD from four 32G x 4mm PN devices (investigational BD Nano™ PRO and three commercial PN devices; n=75/device/force, 1200 total) were measured by fluoroscopic imaging.

The BD Nano™ PRO more closely achieved the 4mm target NPD with significantly less variability (p<0.006) than the commercial PN devices across injection forces. Estimates of IM injection potential, calculated using human tissue measurements, displayed a commensurate reduction in IM risk.

Quantifiable differences observed between PN devices indicate that design features, coupled with aspects of variable use, influence injection consistency. The BD Nano™ PRO design may reduce impact of unintended individual injection technique differences and IM injection potential, which could decrease insulin absorption variability leading to more consistent glycemic control.


C. Rini: Employee; Self; Becton, Dickinson and Company. B.C. Roberts: Employee; Self; Becton, Dickinson and Company. D. Morel: Employee; Self; Becton, Dickinson and Company. R. Klug: None. B.L. Selvage: None. R.J. Pettis: Employee; Self; Becton, Dickinson and Company. Stock/Shareholder; Self; Becton, Dickinson and Company. Research Support; Self; JDRF. Board Member; Self; JDRF.

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