Comparison of subdermal and perforator delay techniques on a rat flap model

Comparison of the Effect of Delay Phenomenon and Quercetin Application on the Viability of Dorsal Skin Island Flaps in Rats: An Experimental Study

BACKGROUND

Surgical delay is any surgical intervention performed 7-14 days before flap elevation, separating part of flap from its vascular bed and aiming to decrease flap necrosis. However, delay surgery needs to be planned and performed as a separate surgical operation. Quercetin is a flavonoid with anti-inflammatory, and vasodilator effects. This study compares the effects of quercetin and surgical delay on flap survival.

MATERIALS AND METHODS

The study included 32 male Wistar rats divided into four groups: control group (group 1), surgical delay group (group 2), quercetin group (group 3), and both surgical delay and quercetin group (group 4). All dorsal skin island flaps were elevated based on deep circumflex iliac artery and 7 days were selected as waiting period after flap elevation, 50 mg/kg (0.5 mL) intraperitoneal quercetin administration period, and surgical delay period. Macroscopically flap necrosis rates were calculated and histopathological examination was performed to evaluate number of vessels, vessel lumen diameters, inflammation, epidermal damage, and dermal fibrosis scores. All rats were euthanized.

RESULTS

Flap necrosis rates, inflammation, epidermal damage, and dermal fibrosis scores of group 3 and 4 were found to be lower than group 1 and 2 ( P < 0.05). Vascular lumen diameter of group 2, 3, and 4 were found to be higher than group 1 ( P < 0.05) but no statistically significant difference was found for this parameter between group 2, 3, and 4 ( P > 0.05). The number of vessels were found to be higher in group 2, group 3, and group 4 compared with group 1, but this difference was not to be found statistically significant ( P = 0.534).

CONCLUSIONS

This study shows that quercetin application is more effective in reducing flap necrosis rates and anti-inflammatory effect than surgical delay and also has superior effect in terms of vasodilation.

Comparison of incisional delay patterns on a rat random flap model

One of the simplest form of surgical delay can be performed by placing an incision around the flap without undermining, prior to flap elevation. In this study, we have compared the efficiency of different patterns of skin incision to improve flap survival. Twenty-eight animals were used in four groups. Incisional delay was performed prior to flap elevation in the three experiment groups. Complete incision of the three flap edges was performed in the all experiment groups with the exception of an intact skin section on the middle 1/3rd of the bilateral edges in group 1 (bilateral skin edge preserved delay: BSEPD), of a unilateral edge in group 2 (unilateral skin edge preserved delay: USEPD) and of the superior edge in group 3 (superior skin edge preserved delay: SSEPD) without any undermining. Two weeks following the delay procedure, dorsal skin flaps were raised and reinserted back to their place. The results were evaluated with the measurement of necrotic flap area, microangiographic imaging and histological evaluation. The mean percentage of necrotic flap area to whole flap area was 16.94%, 7.54%, 23.34% and 50.6% in the BSEPD, USEPD, SSEPD and control groups, respectively. In selected microangiographic images, vessels were more prominent in the delay groups. The results of the study indicate that three sided incision with an intact skin on the superior edge is not effective in providing a sufficient delay and flap survival improvement when compared to incisions with intact skin on the unilateral and bilateral edges.