The SNaP system: biomechanical and animal model testing of a novel ultraportable negative-pressure wound therapy system.
BACKGROUND
Negative-pressure wound therapy is traditionally achieved by attaching an electrically powered pump to a sealed wound bed and applying subatmospheric pressure by means of gauze or foam. The Smart Negative Pressure (SNaP) System (Spiracur, Inc., Sunnyvale, Calif.) is a novel ultraportable negative-pressure wound therapy system that does not require an electrically powered pump.


METHODS
Negative pressure produced by the SNaP System, and a powered pump, the wound vacuum-assisted closure advanced-therapy system (Kinetic Concepts, Inc., San Antonio, Texas), were compared in vitro using bench-top pressure sensor testing and microstrain and stress testing with pressure-sensitive film and micro-computed tomographic scan analysis. In addition, to test in vivo efficacy, 10 rats underwent miniaturized SNaP (mSNaP) device placement on open wounds. Subject rats were randomized to a system activation group (approximately -125 mmHg) or a control group (atmospheric pressure). Wound measurements and histologic data were collected for analysis.


RESULTS
Bench measurement revealed nearly identical negative-pressure delivery and mechanical strain deformation patterns between both systems. Wounds treated with the mSNaP System healed faster, with decreased wound size by postoperative day 7 (51 percent versus 12 percent reduction; p < 0.05) and had more rapid complete reepithelialization (21 days versus 32 days; p < 0.05). The mSNaP device also induced robust granulation tissue formation.


CONCLUSIONS
The SNaP System and an existing electrically powered negative-pressure wound therapy system have similar biomechanical properties and functional wound-healing benefits. The potential clinical efficacy of the SNaP device for the treatment of wounds is supported.
Fong
Kenton D
KD
Stanford and Sunnyvale, Calif. From the Division of Plastic and Reconstructive Surgery, Department of Surgery, Stanford University School of Medicine, Stanford University; the Department of Bioengineering, Stanford University; and Spiracur, Inc.
Hu
Dean
D
Eichstadt
Shaundra
S
Gupta
Deepak M
DM
Pinto
Moshe
M
Gurtner
Geoffrey C
GC
Longaker
Michael T
MT
Lorenz
H Peter
HP
D000818:Animals; D001696:Biomechanical Phenomena; D004867:Equipment Design; D006097:Granulation Tissue / Q000502:physiology; D054843:Negative-Pressure Wound Therapy / Q000295:instrumentation; D011312:Pressure; D051381:Rats; D014618:Vacuum; D014945:Wound Healing