Hyperbaric oxygen therapy for pediatric "hypospadias cripple" – Evaluating the advantages regarding graft-take

Summary Introduction Hypospadias cripple patients pose a major surgical challenge with high complication rates attributed mainly to graft contraction. Hyperbaric oxygen therapy (HBOT) is an established treatment for compromised grafts, and used extensively as a salvage therapy for compromised grafts and ischemic non-healing wounds. Objective We evaluated the graft take rates in hypospadias cripple cases undergoing a 2-stage tubularized auto-graft repair (STAG), and compared between patients treated with or without preemptive HBOT. Materials and methods All patients underwent a 2-stage tubularized auto-graft repair (STAG). Patients receiving preemptive HBOT were compared to patients receiving the standard surgical procedure without HBOT. The HBOT protocol included a daily session, 5 days per week for four weeks prior to the surgery and 10 additional daily sessions immediately after first stage surgery. Each HBOT session included 90 minute exposure to 100% O2 at 2 atmospheres absolute (ATA) with 5 minute air breaks every 20 minutes. The primary endpoint was graft take. Sequential tubularization without tension at second stage was defined as success. Results Seven boys received HBOT and 14 boys comprised the control group. All patients in the HBOT group had good graft take with no graft contraction. In the control group, 57% had good graft take and could proceed to the 2nd stage surgery, 43% had graft contraction (Table). Except for one patient who had claustrophobia while entering the chamber, no significant side effects developed during the HBOT. Discussion The basic pathophysiology of compromised flaps includes both ischemia and reperfusion injury, which can be attenuated by HBOT. The beneficial effects of HBOT relates to several mechanisms, including hyper-oxygenation, fibroblast proliferation, collagen deposition, angiogenesis, and vasculogenesis. Graft contraction is a well-known complication in hypospadias cripple population with reported failure rate of 39-63%. The HBOT procedure was found to be very effective and the entire HBOT group had a good graft take. Accordingly, all patients in the HBOT group proceeded to a successful 2nd stage tubularization. In addition, HBOT was found to be safe and generally well tolerated by this pediatric population. Study limitations were a relative small, non-homogenous sample size, and lack of prospective randomization. Success was defined as sufficient graft elasticity sufficing for tubulirization of the neourethra, and exact graft measurements are lacking in our study. Conclusions Preemptive HBOT can be used safely in the hypospadias cripple pediatric population and can potentially reduce the expected high surgical failure secondary to graft contraction.