The Effect of Lateral Approximations on the Survival of the Free Composite Flap

Non-vascularized free composite graft is one of the simple and effective reconstructive options, but its clinical use has been limited due to questionable survival rate. Early vascularization is essential for graft survival and is mainly carried out via recipient bed or repaired sites. This study was designed to investigate the effect of the lateral marginal approximations on the survival of the free composite flap using a model of skin-subcutaneous composite graft in rats. Thirty 1.5 x 1.5 cm2 sized square shape composite flaps were elevated freely and reposed in place immediately on the dorsum of five Sprague-Dawley rats, and divided into five groups of six flaps. In all groups, graft bed was isolated with silastic sheet. In the group I, all sides of flap were repaired with blockage of silastic sheet insertion. Three, two, and one sides of flap were treated with same method in the group II, III, and IV respectively. Other sides of flaps were repaired without blockage, so all sides of flap were repaired in the group V. At 14 days later, the survived rate of each flap was evaluated according to the numbers of the repair sites. Histological examination was done for the evaluation of new vessel development quantitatively. Overall survived rates were increased with the number of repaired sites, but the group V only showed increased survival rate up to more than fifty percentile of the flap size with a significant difference statistically. New vessels were also increased in proportion with the number of repaired sites, and the repair site more than two had significant effect on the increased number of new vessels. In conclusion, at least more than threefourth of flap circumference should be repaired in order to increase flap survival effectively under the condition of bed isolation.

Free Toe Tissue Transfer using Infiltration Method of Local Anesthetic Agent

This study was designed to introduce free toe tissue transfer using infiltration method of local anesthetic agent. Four toe pulp tissues were transferred to reconstruct finger tip defect in four patients who were not suitable for general anesthesia. Two flaps taken from the lateral side of the great toe was used for reconstruction of thumb defect and two flaps from the medial side of the second toe for resurfacing of the index and fifth finger. Flap sizes were various from 2.0x2.0 cm2 to 1.6x4.0 cm2. Anesthesia was induced by infiltration of 2% lidocaine hydrochloride (with 1:100,000 epinephrine) with dilution of normal saline in same volume unit, as like as in ordinary digital block. All vessels were anastomosed within 2 cm of distance from the proximal margin of the defect. Whole operative procedures were carried out by one team. All flaps were successfully taken without complication. The average operation time was 4 hours 10 minutes. The amount of anesthetic agent used in whole operative procedures was roughly 4 mL in the toe, 8 mL in the finger, and 12 mL totally. In conclusion, free toe tissue transfer using infiltration method of local anesthetic agent would be good strategy for finger tip reconstruction in the patient not suitable for general anesthesia.