A randomized controlled trial of platelet rich fibrin PRF versus dartos flap use in TIP urethroplasty in anterior hypospadias A pilot study

This a prospective randomized controlled pilot study in which we will be focusing on the outcomes and benefits in using autologous Platelet rich Fibrin membrane (PRF)  as 2nd coverage layer in Snodgrass Tubularized Incised plate (TIP) urethroplasty. All primary cases between 18 months to 12 years of age diagnosed with distal and mid-penile hypospadias with minimal/no chordee will be included in the study. We have a total sample size of 42 patients which will be divided into two groups after randomization. Group A  will be provided with autologous PRF membrane  and group B will be provided with traditionally used Dartos flap as 2nd coverage layer in Snodgrass TIP urethroplasty.  There are high complication rates with traditional techniques being used like dartos flaps/tunica vaginalis flaps with urethrocutaneous fistulas being one the most common. Platelet rich fibrin membrane is being used because of its  better tolerance, immunogenic properties,  lesser /minimal chances of allergic reaction and its promising results in promoting natural wound healing.

PRF membrane will be made by using 10-20ml of patients venous blood collected in a blood bag having CPDA (Citrate-Phosphate-Dextrose and Adenine) as anticoagulants.

This whole blood will then be transferred into a sterile tube using a blood transfusion set.  PRF will be prepared with the double spin platelet pellet method. Using a tabletop centrifuge , the initial spin will be done at 1300rpm for 15 mins. The supernatant plasma (which has all the platelets and a few WBCs) will be pipetted out and transferred to another sterile tube. Inj. calcium gluconate will be diluted with normal saline (1:7) to make calcium content (M/40) inside the biosafety cabinet, under aseptic conditions. This calcium solution will be added before second step of centrifugation. It causes formation of autogenous thrombin but prevents activation of platelets. It will then be subjected to a second spin at 2300 rpm (885g) for 5 min. During 2nd step of centrifugation, dense fibrin network will be formed (Fig 1). Intact platelets will be trapped in this matrix. Fibrin acts as scaffold and trapped platelets slowly release growth factors GFs over a period of 7 days. Thereafter the final step will be securing the fixation by using a few 6–0 interrupted polyglactin/Vicryl sutures.

Postoperative course and outcomes will be compared among both groups in the subsequent follow up at POD 3 and at the end of 1st,2nd and 3rd month. Our main objective shall remain the comparison in the urethrocutaneous fistula rate between the two groups as we hypothesize that use of Platelet rich fibrin membrane has a low urethrocutaneous fistula rate in comparison with traditional dartos flap when they are used as coverage layer over urethroplasty.