ABSTRACT
The effect of hyperbaric oxygen (HBO) on axial pattern skin flap survival in male
Wistar rats, when administered during and immediately following prolonged total flap
ischemia, was evaluated. Eighty-one 3 × 6 cm rectangular epigastric skin flaps were
elevated, and the inferior epigastric pedicle of each flap occluded for 8 hr. The
animals were divided into a control and three other experimental groups: Control (n
= 27)-8 hr flap ischemia, no HBO; Group 1 (n = 21) - HBO therapy (100 percent O2-three 1.75 hr dives at 2.5 atm) during ischemia; Group 2 (n = 21) - HBO therapy (two
1.75 hr dives) following ischemia; Group 3 (n = 12) - HBO treatment during ischemia
but with the flap contained in a metal-coated Mylar bag to prevent oxygen diffusion.
The percentage of flap necrosis was calculated on postoperative day 6.
Mean flap necrosis for controls was 28 percent (± 21 S.D.), while HBO treatment during
ischemia or during reperfusion significantly reduced this necrosis to 9 percent (±
11) and 12 percent (± 14), respectively (p < 0.01). The percentage of necrosis for Group 3, with the local effect of HBO on
the flap blocked by the diffusion barrier, was 5 percent (± 7), also significantly
better than the controls (p < 0.0005) but no different from the other two experimental groups.
HBO treatment increases the percentage of axial pattern skin flap survival when administered
during or immediately following total flap ischemia. The improved flap survival appears
to be a systemic and not a local effect.
