Perfusion, viability, and pedicle dependence in acute and delayed rat island skin flaps.
OBJECTIVE
Although surgical delay phenomenon has been widely investigated, its pathophysiology has not been fully elucidated.


METHODS
In 25 Spraque-Dawley rats, an 8 x 8 cm2 epigastric skin flap consisting of 4 vertical zones A through D (farthest from vascular pedicle) was outlined. All animals were perfused twice with colored fluorescent microspheres: immediately before and after flap elevation (Acute, n = 10) and before and after pedicle ligation on POD 8 (Delayed, n = 15).


RESULTS
After acute flap elevation, peripheral perfusion dropped significantly in zone C (0.29 +/- 0.01 vs. 0.19 +/- 0.04 ml g(-1) min(-1); P < 0.01) and zone D (0.33 +/- 0.09 vs 0.01 +/- 0.01 ml g(-1) min(-1); P < 0.01), while global flap perfusion remained unchanged. Total and regional blood flow did not change in the Delayed group after pedicle ligation.


CONCLUSIONS
Elevation of a pedicled flap caused significant decrease in distal flap perfusion while maintaining proximal and total flap perfusion. Eight-day delay was adequate to establish sufficient flap perfusion independent of the vascular pedicle.
Komorowska-Timek
Ewa
E
Division of Plastic and Reconstructive Surgery, Loma Linda University, Loma Linda, CA 92354, USA. etimek@sbcglobal.net
Timek
Tomasz A
TA
Brady
Sandra
S
Buncke
Harry J
HJ
D000818:Animals; D010477:Perfusion / Q000295:instrumentation / Q000379:methods; D051381:Rats; D017207:Rats, Sprague-Dawley; D012039:Regional Blood Flow / Q000502:physiology; D013524:Surgical Flaps / Q000098:blood supply* / Q000502:physiology; D013997:Time Factors