"A method for quantitative analysis of lumen changes in microvascular anastomoses"Cook, A F; Grossman, J A; Herpy, E S; Dinner, M I
"The effects of storage media and perfusion on osteoblast and osteocyte survival in free composite bone grafts"erggren A; Weiland AJ; Ostrup LT; Dorfman H
GRANTS:1-R01-AM25791-01/AM/NIADDK NIH HHS/United States
Twenty-two adult mongrel dogs were used to investigate the effects of storage alone and storage and perfusion in 3 different storage media on the survival of osteocytes and osteoblasts in free bone grafts revascularized by microvascular anastomoses. Evaluation of the grafts at 2 weeks demonstrated that storage in chilled (+ 5 degrees C) physiologic saline or Collins-Terasaki solution resulted in greater survival of osteocytes and osteoblasts than did storage in chilled BGJb solution or in room temperature air. No beneficial effect could be detected from perfusing the bone grafts with their storage media. On the contrary, deleterious effects were noted at the sites of the anastomoses, with thromboses of vessels secondary to endothelial damage.
"The effects of preservation on microvascular vein grafts in rats"Razaboni RM; Greco MA; Harper AD; Shaw WW; Ballantyne DL
Segments 15 mm in length were excised from the femoral veins of rats and preserved by refrigeration at 4 C in lactated Ringer's solution for periods up to 21 days. The findings show that veins can be preserved for up to seven days and successfully grafted to recipients. Although there was some success in preserving vein segments for more than seven days, a high rate of thrombosis occurred after implantation in the recipients. It is generally accepted that damaged endothelium causes thrombosis. The light and electron microscopic observations in this study, however, suggest that the condition of the endothelium may not be the only important factor in the patency of small vessels. A thickened and prominent elastic lamina may also play a role in keeping the lumen open.
"Transcutaneous PO2 monitoring for assessing viability and predicting survival of skin flaps: experimental and clinical correlations"Serafin D; Lesesne CB; Mullen RY; Georgiade NG
Rectangular skin flaps based on the right superficial epigastric vessels were designed on the groins of 36 rats. Preoperative control, intraoperative, and postoperative readings of oxygen tension (PO2) were made at proximal, central, and distal sites on the flaps with a transcutaneous PO2 (tcPO2) monitor under various conditions of oxygen inspiration. The results of this experimental work indicated that the tcPO2 monitor was useful in continuously and rapidly measuring changes in oxygen concentration in skin flaps in a noninvasive fashion. The monitoring demonstrated that the response time of the flaps to changes in the concentration of inspired oxygen was rapid (less than 15 seconds). The monitoring also was valuable in assessing viability of the flaps, in predicting flap survival, and in detecting any systemic factors influencing oxygen transport, such as pneumonia. As a result of the experimental series, tcPO2 monitoring was used clinically to evaluate 18 flaps in 16 patients. As in the experimental series, the clinical measurements were significant and reproducible. They demonstrated that the tcPO2 monitor provides safe, reliable monitoring of peripheral oxygenation in the microcirculation that is rapid, continuous, and totally noninvasive. It is concluded that simultaneous tcPO2 measurements at control and flap sites provides a continuous record of the status of a flap that can improve the postoperative management of the surgical patient.
"The effects of short-term preservation on microvascular free groin flaps in rats"Ballantyne DL; Reid CA; Harper AD; Shaw WW
Free groin flaps taken from rats were preserved by refrigeration at 4 degrees C in either lactated Ringers solution or tissue culture medium for various periods of time. The results indicate that a high survival rate can be expected at periods up to 72 hours, but there was no success in preserving flaps longer than 72 hours. These preliminary experimental findings suggest that, clinically, a high survival rate can be achieved in free flaps following excision from donor sites even if the microvascular transfer must be postponed for a period up to but not exceeding 48 hours.
"The microvascular technique of vein grafting in rats as a training and experimental model"Razaboni RM; Ballantyne DL; Harper AD; Shaw WW
Techniques for obtaining and implanting vein grafts in the femoral arteries of rats are described. Grafts 5 mm in length can be removed from the femoral vein without ligating any side branches; a 15-mm segment is the maximum graft that can be obtained from the femoral vein in a rat. This requires ligation and division of all the branches between the inguinal ligament and the great saphenous vein. The superficial epigastric vein also can be used as a source of grafts to be used in the femoral artery. In this study, neither the femoral nor the superficial epigastric vein appeared to have functioning valves. Therefore, reversing the vein graft before implantation was not necessary.