Incidence of Urethrocutaneous Fistula With and Without Caudal Epidural Block

Overview

The study is designed to explore any association between the caudal epidural block(CEB) given for perioperative analgesia and the occurrence of urethrocutaneous fistula postoperatively in children undergoing distal hypospadias repair .We also intend to study the duration of penile engorgement due to CEB causing penile oedema which may subsequently play a role in fistula formation. The pilot study will recruit children under 8 years of age diagnosed with distal hypospadias scheduled to undergo Tubularised Incised Plate Urethroplasty, operated by a single paediatric surgeon. General anaesthesia will be induced with sevoflurane in oxygen nitrous oxide mixture supplemented by fentanyl citrate and atracurium besylate in all children. LMA Pro SealTMof appropriate size will be inserted. Children in group I will then be given caudal epidural block (CEB) as per our practice protocol. Children in group II will be given additional intravenous fentanyl citrate. All children will be followed postoperatively till 3 months to evaluate incidence of urethtocutaneous fistula. The prospective study attempts to eliminate previously reported confounding factors.

CEB is routinely used along with general anaesthesia for inguinal and genital surgeries. It provides intraoperative and postoperative analgesia, is safe, simple and has success rate of more than 90% in children.It decreases the requirement of inhalational anaesthetics and narcotics, decreases stress hormone release and facilitates early recovery. Hypospadias is the most common congenital anomaly of penis, incidence being 1 in 300 live births. Hypospadias repair is a technical procedure that can be associated with significant complications such as meatal stenosis, stricture, glans dehiscence and flap necrosis Urethrocutaneous fisula formation is the most common complication after primary repair with an incidence of upto 20%. There have been controversies regarding the association of CEB with urethrocutaneous fistula. Some studies have reported a high incidence of postoperative urethrocutaneous fistula in children who received CEB while others have not confirmed any such relationship. Association between urethrocutaneous fistula and site of urethral opening, age of patient, duration of surgery, surgeon's expertise, use of subcutaneous epinephrine and use of preoperative testosterone has been found. Penile engorgement, post inflammatory response and tissue oedema may be contributory factors for development of fistula. However any association between CEB and fistula formation is not clear. All studies, except one, are retrospective, limited by small sample size and presence of various confounding factors. The present study is aimed to explore any association between CEB and urethrocutaneous fistula. The study will be conducted in children with distal hypospadias only; they will be operated by a single surgeon, without the use of subcutaneous epinephrine, so that any association, if at all between CEB and urethrocutaneous fistula becomes evident.