The Bladder Flap at Cesarean Delivery: Establishing Evidence for Practice

BACKGROUND

Cesarean section is the most common major surgical procedure in women world wide. In the United States almost 25% of deliveries are by cesarean section and the rate continues to rise [1]. In performing this procedure, it is imperative that evidence based techniques are utilized to optimize outcomes and minimize complications. Recently, the case has been made for simplifying the procedure by eliminating unnecessary and potentially harmful steps [2].

Rationale for the Bladder Flap Challenged: While the creation of the bladder flap has long been an integral part of the standard cesarean section, there is no evidence of benefit. Creation of the bladder flap at cesarean section dates back to the pre-antibiotic era of the 19th century. One rationale was to enable the surgeon gain access to the lower uterine segment while minimizing injury to the bladder [3]. While some older case reports suggested inadequate bladder flap reflection as a risk factor for bladder injury, it has not been collaborated [4]. On the contrary, several studies have identified difficulty encountered while developing the bladder flap as a risk factor for bladder injury at cesarean section [5, 6]. Although uncommon, creation of the bladder flap may also be associated with complications such as bladder flap hematoma and dysuria, sometimes requiring re-operation to drain the collection or release the bladder flap [7-11]. It has also been suggested that disruption of the autonomic innervations by creation of the bladder flap results in an increased incidence of urinary retention. In the long term, creation of the bladder flap may result in thick adhesions in the lower uterine segment that may lead to difficult subsequent cesarean delivery and bladder perforation [3].

Another rationale for the creation and subsequent closure of the bladder flap was to protect the peritoneal cavity from intrauterine infection. With the use of antibiotics, closure of the bladder flap has been demonstrated to be unnecessary and associated with increased morbidity including febrile morbidity, adhesions and upward dislocation of the urinary bladder [12, 13]. This evidence resulted in abandonment of closure of the bladder flap at cesarean section. Yet its creation has remained part of standard practice.

Limited Data on Role of Bladder Flap: Data on the role of the bladder flap in cesarean section is very limited. A simplified method of cesarean section (Pelosi-type) involving omission of the bladder among other modifications has been shown to be safe and cost saving [2]. Only one published study evaluated omission of the bladder flap as the only modification [14]. This single randomized trial compared omission of the bladder flap in 53 patients to the standard technique of cesarean section in 49 patients. The results showed significant short term benefits of omitting the bladder flap including a reduction in operating time, blood loss, postoperative pain and microhematuria.