A novel murine island skin flap for ischemic preconditioning.
BACKGROUND
Ischemia reperfusion injury is a well-known phenomenon affecting skin flap viability. One method to improve flap viability is ischemic preconditioning. Previous murine flap models used random flaps. We developed a single pedicle island skin flap which allows us to create true ischemia by clamping the single pedicle. Our first aim was to describe a novel murine skin flap model with a definable, reproducible injury. Our second aim was to test the usefulness of this model by demonstrating mitigation of injury via ischemic preconditioning.


METHODS
Dorsal lateral thoracic artery pedicle island skin flaps (3.5 x 1.5 cm) were elevated in 39 male C57/BL6 mice: a Control group (n = 7), 10 h of ischemia (n = 21), and Preconditioning (2 cycles of 20 min ischemia: 20 minutes reperfusion) + 10-h ischemia (n = 11). After flap elevation, a silicon sheet barrier was placed. The axial pedicles were occluded, and the flaps were inset with 6-0 prolene. In all mice, ischemia was followed by 1 wk of reperfusion. At 1 wk, percent necrosis was measured and an analysis of variance was performed.


RESULTS
The percent of flap necrosis was 1.1% +/- 1.11% in controls. Animals that were subjected to 10 h of ischemia developed 33.14% +/- 7.23% necrosis. Preconditioned animals that underwent 10 h of ischemia demonstrated a 43% reduction in necrosis (18.82% +/- 5.68%). There was a statistically significant difference among all groups (P < or = 0.001).


CONCLUSIONS
Rat models have been the standard for skin flap experiments. We have developed a novel murine single pedicle island skin flap model with reproducible injury. This model has numerous advantages, including ease of handling, low cost, appropriateness for biomedical studies, and the availability of genetically altered animals. We also confirmed this model's usefulness in a study of mitigation of ischemia reperfusion injury through ischemic preconditioning.
Tatlidede
Soner
S
Plastic Surgery Research Laboratory, Division of Plastic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114, USA.
McCormack
Michael C
MC
Eberlin
Kyle R
KR
Nguyen
John T
JT
Randolph
Mark A
MA
Austen
William G
WG
D000818:Animals; D062109:Dermatologic Surgical Procedures; D019194:Ischemic Preconditioning / Q000379:methods*; D051379:Mice; D008810:Mice, Inbred C57BL; D009336:Necrosis; D051381:Rats; D015427:Reperfusion Injury / Q000517:prevention & control; D013524:Surgical Flaps / Q000098:blood supply / Q000473:pathology / Q000502:physiology*; D013895:Thoracic Arteries / Q000601:surgery; D014945:Wound Healing