Management of ischemic tissues and skin flaps in Re-Operative and complex hypospadias repair using vasodilators and hyperbaric oxygen

Introduction: Repeated and multiple surgeries for hypospadias result in varying degrees of scarring and hypovascularity of penile tissues which may result in poor healing and increasing complication rates with each additional repair. Vasodilator agents such as Nitroglycerine (NTG) can be helpful in the immediate postoperative period to improve flap viability. Hyperbaric oxygen therapy (HBOT) has well-established benefits to promote angiogenesis and wound healing. We hypothesized that NTG and HBOT, methods to promote blood flow and wound healing, would provide better outcomes in redo hypospadias surgeries and reduce complication rates; and, that HBOT and NTG would provide better outcomes compared to NTG alone.

Objectives: Herein, the authors review the results of their strategy of the past 5.5 years in managing these compromised hypovascular tissues using 2% NTG and HBOT for redo surgery of hypospadias.

Study design: Between 2014 and 2019, 82 patients (2-24 years old) exhibiting varying degrees of scarring of skin and subcutaneous tissues underwent re-operative repair of hypospadias complications following failed surgeries (3-9 operations, average 5.5 failed previous repairs). There were two groups of patients: Group I (49 patients) received trimodal therapy consisting of NTG, HBOT, and local steroids. The patients were examined every 3 weeks and every 3 months thereafter. The postoperative site was photographed by the parents or by the older patient prior to each visit. Group II (33 patients) received NTG and local steroids, but not HBOT for various reasons.

Results: In Group I: 44/49 (88.8%) of the repairs were successful. The complications in this group included a distal repair breakdown (n = 2) and urethral fistula (n = 3). In Group II, a successful outcome was noted in 23/33 (69.6%). The follow up of the 78 patients who completed their repairs varied between 5 months and 4 years. Results are highlighted in the table.

Discussion: In accordance to previously published data, the study results further support promising outcomes of application of NTG and HBOT to improve flap viability. Limitations include non-randomization of our treatment groups resulting in a retrospective evaluation of our protocol; and, the intrinsic heterogeneity of our patient population, previous surgical repairs, and scar tissues.

Conclusions: The proposed treatment of combining NTG and HBOT appears to result in reversal of tissue hypoxia and improved wound healing. This preliminary report shows improved outcomes with less morbidity in a group of patients with multiple hypospadias surgical failures and it warrants further application in a larger number of patients.

Keywords: Hyperbaric oxygen; Nitroglycerine; Redo hypospadias; Skin flap ischemia.