Downloaded from http://journals.lww.com/annalsplasticsurgery by BhDMf5ePHKbH4TTImqenVHHw8h8Dt9kei2HMH/f7/YgiOxHLrnB5YXEYCLxpSFAe on 07/03/2020 Platelet-Rich Plasma for Skin Graft Storage An Experimental Study Using Rabbit Ears Ali Gökkaya, MD, a Metin Görgü, MD, a Jehat Kızılkan, MD, a Ertuğrul Karanfil, MD, a Ali Doğan, MD, a and Hesna Müzeyyen Astarcı, MD b Background: Storage of surplus grafts for later use is one of the standard proce- dures used in plastic surgery. For the delayed use of skin grafts, various methods and media have been investigated for short-term storage. This study aimed to in- vestigate the effect of platelet-rich plasma (PRP) skin graft storage on the survival of skin grafts obtained from rabbit ears. Materials and Methods: Twelve rabbits were used in this study. A total of 12 skin grafts measuring 1 Â 1 cm 2 were obtained from the inner surfaces of the rab- bits' ears. The grafts were stored at +4°C in saline, Hartmann's, and PRP media. On days 3, 7, 10, and 14, the grafts were implanted into the ears in areas measur- ing 1 Â 1 cm 2 where the skin, cartilage, and perichondria were excised. After the implantation of the grafts, the survival rates were evaluated by measuring the graft areas on day 0, day 10, and day 30. Results: The graft survival rate decreased as the storage period increased in all 3 of the media. The decrease in survival rate was higher in the grafts that were stored in the Hartmann's media in comparison with the saline and PRP media, and the difference was statistically significant. The decrease in graft survival was similar between the storage in saline and PRP media; however, the differences were statistically insignificant. Conclusions: Although in vitro criteria are important for evaluating graft sur- vival, in vivo studies showing the graft take rate in the recipient area are required. When the in vivo criteria are evaluated, the use of PRP is not superior to the use of saline for graft storage. However, additional studies are required to evaluate the effects of PRP media on graft quality. Key Words: skin graft, storage, preservation, platelet-rich plasma, rabbit ears, secondary contraction (Ann Plast Surg 2020;85: 68–75) R eliable short-term skin graft preservation is desirable in particular clinical situations, such as burn surgery and also for defects where the circulation is partially compromised. In plastic surgery, grafts in short-term storage are generally used for delayed grafting purposes, for example, if the initially adapted grafts do not take or if the unaccept- able receiving areas during operation become ready in subsequent days. 1–3 The viability of stored grafts must be maintained for the re- quired process because the presence of a prepared graft will allow the defect or wound to be covered without requiring a new operation. Sur- plus skin grafts are cooled and safely maintained in various solutions for up to 10 days. In plastic surgery, protecting the skin grafts wrapped in saline-soaked gauze in a refrigerator at +4°C is the preferred method for skin graft storage because it is simple and easy. 1,2,4 Nutritional and/or protective solutions of different properties have been tested for the long-term preservation of skin grafts. 2,4,5 Although current tech- niques for graft storage are successful and inexpensive, the graft-intake rate decreases and graft viability and quality deteriorate with longer preservation times. Different methods and storage environments are be- ing developed to increase the graft preservation time and preserve the amount and quality of graft survival in the recipient area. The aim of the present study was to investigate graft storage techniques and mate- rials that are cheaper and easier to manage. To be considered superior, new methods should offer longer preservation times, with at least the same survival rate or better graft quality than existing methods. The present study used platelet-rich plasma (PRP) because of its physiolog- ical and autologous properties, and it is investigated the survival rates of the grafts that were stored in PRP after they were implanted. MATERIALS AND METHODS The study was approved by the Abant Izzet Baysal University Animal Ethics Committee (2017/199). Twelve female New Zealand white rabbits, weighing 2 kg to 3 kg, were used in the experiments. All proce- dures were performed under general anesthesia using ketamine hydro- chloride (35 mg/kg) (Ketalar, Eczacıbası-Baxter, Turkey) and xylazine (5 mg/kg) (Rompun, Bayer, Germany). A total of 12 skin grafts measur- ing 1 Â 1 cm 2 were harvested from the inner surface of the rabbits' ears (6 grafts from the right ear and 6 from the left ear) (Table 1). The grafts were stored at +4°C in saline, Hartmann's, and PRP media for 3, 7, 10, and 14 days (Table 1). In the right ears of the rabbits, 2 columns, consisting of 3 to 1 cm 2 areas, were created. The external columns were used to implant the grafts that were stored for 3 days. The internal columns were used to implant the grafts that were stored for 7 days (Figs. 1-3). The same procedure was performed on the left ear for the implantation of the grafts that had been stored for 10 days and 14 days (Figs. 1, 2, 4). The grafts implanted into the rabbit ears were photographed on day 10, day 30, and day 90 (Figs. 3-5) and evaluated with a dermatoscope (Figs. 3-5). After 3 months (90 days), punch biopsies were taken from the central points of the grafts before the rabbits were sacrificed (Fig. 3). After suturing, 1-mm celluloid graph paper was placed on the graft, and the areas of the grafts were measured. The areas of the grafts that had survived on day 10 and day 30 were measured by the same way. The survival percentage was then calculated, as follows: survival per- centage = surviving graft area mm 2 / initial graft area mm 2 Â 100. Sta- tistical analysis was performed to evaluate the values of the viable areas of the grafts. Grafts A 1-cm 2 full thickness skin graft (FTSG) was harvested from the inner surface of the rabbits' ears, just over the perichondrium. The donor area was left exposed and treated with antibiotic ointment. Every piece of the graft was stored immediately in a refrigerator at +4°C after wrap- ping it in a media-soaked gauze and placing it in a sterile bottle. Receiving Area Preparation On the day of implantation, cartilaginous tissue and the perichon- dria were excised from inner sides of the rabbits' ears, and the 1 cm 2 re- cipient sites were prepared, which consisted of subcutaneous tissue of Received April 29, 2019, and accepted for publication, after revision November 26, 2019. From the a Departments of Plastic Reconstructive Surgery, and b Pathology, Abant Izzet Baysal University, Bolu, Turkey. Conflicts of interest and sources of funding: This project was supported by the BAP (Scientific Research Project) unit of Abant İzzet Baysal University (project number, 2018.08.18.1394). The authors declare no conflict of interest. Reprints: Metin Görgü, MD, Department of Plastic Reconstructive Surgery, Abant Izzet Baysal University, Gölköy, Bolu, Turkey 14280. E-mail: metingorgu@gmail.com. Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved. ISSN: 0148-7043/20/8501–0068 DOI: 10.1097/SAP.0000000000002253 RESEARCH 68 www.annalsplasticsurgery.com Annals of Plastic Surgery • Volume 85, Number 1, July 2020 Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.