[Histologic effects of hyperbaric oxygen therapy administered immediately after or two hours after ischemia-reperfusion injury: a rat abdominal skin flap model].
OBJECTIVE
In a rat abdominal skin flap model, we investigated the histologic effects of hyperbaric oxygen (HBO) therapy on the skin flaps and the lung tissue immediately after and two hours after ischemia-reperfusion injury (IRI).


METHODS
Thirty Sprague-Dawley rats were assigned to three groups equal in number. The first group was left as controls. The left inferior abdominal skin flap based on the superficial inferior epigastric vessels was elevated. Following 10 hours of global ischemia, HBO therapy was started immediately after and two hours after reperfusion in groups 2 and 3, respectively. Our protocol included a course of 16 HBO treatments in six days at 2.5 ATA for 90 minutes, with four sessions on the first day, three sessions on the second and third days, and two sessions on the fourth, fifth, and sixth days. On the sixth day, survival rates for all flaps were calculated. Histologic examination was made on specimens taken from rat flaps and lungs.


RESULTS
The mean flap survival was 25.87% in the control group. It significantly increased to 90.93% and 84.34% in HBO-treated rats in groups 2 and 3, respectively (p<0.001). There was no significant difference between HBO-treated groups (p>0.05). Histologically, neither minor nor major changes were observed in HBO-treated rat lung tissues. Similarly, compared to the controls, thrombosis in flap microvasculature, intimal damage, edema, neutrophil infiltration, and necrosis were considerably less and neovascularization was significantly higher in HBO-treated flap tissues.


CONCLUSIONS
Intense HBO treatment protocol used in this study significantly increases flap survival in rat axial skin flap model and reduces deleterious effects of IRI.
Ağir
Hakan
H
Department of Plastic and Reconstructive Surgery, Medicine Faculty of Kocaeli University, Turkey. agirhakan@yahoo.com
Mersa
Berkan
B
Aktaş
Samil
S
Olgaç
Vakur
V
D000818:Animals; D004195:Disease Models, Animal; D006085:Graft Survival; D006931:Hyperbaric Oxygenation; D007511:Ischemia / Q000628:therapy; D008168:Lung / Q000098:blood supply*; D055370:Lung Injury; D051381:Rats; D017207:Rats, Sprague-Dawley; D015427:Reperfusion Injury / Q000628:therapy*; D012867:Skin / Q000098:blood supply* / Q000293:injuries; D013524:Surgical Flaps; D013997:Time Factors