While the majority of reported cases of perforation of augmented bladders occur with no history of preceding trauma, there are a reports of perforation occurring following trauma, e.g., after motor vehicle accidents. It is difficult to know whether the augmented bladder is more likely to rupture after abdominal trauma than is the normal, nonaugmented bladder, as such cases occur with very low frequency. It is, however, difficult to imagine
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that a surgical scar is stronger than the 'normal' bladder, and so augmented bladders are very probably at greater risk of spontaneous or traumatic rupture than is the normal, nonaugmented bladder.
These patients usually have underlying conditions such as spina bifida and spinal cord injury, and therefore usually have limited awarness of bladder filling or of pelvic pain. Perforation of an augmented bladder, unless it occurs in a patient with normal sensation, may therefore present a diagnostic challenge because pain, though usually present, is not usually severe enough to make one think that a serious event has occurred. A high index of suspicion is therefore needed to make the diagnosis. The usual presentation is one of abdominal pain that may be vague in onset and nature, fever, or sepsis. The diagnosis may be confirmed by a cystogram, or by CT with contrast instillation into the bladder. However, a normal cystogram or CT does not necessarily exclude a diagnosis of perforation. Where there are clinical sign such as persistent or progressive abdominal disten-tion, one should consider exploratory laparotomy even though imaging studies may be normal. Management usually consists of immediate laparotomy and repair of the perforation, but in cases where there is severe sepsis, this should be managed prior to exploration.
This alternative form of bladder augmentation has gained popularity over the last few years because it avoids the complications associated with harvesting a loop of small bowel and of implanting it into the urinary tract. A disc of detrusor muscle is removed from the dome of the bladder, so increasing bladder compliance and thus improving continence. It is perhaps surprising that more of these bladders do not rupture spontaneously when one considers how very thin the bladder is once the muscle of the detrusor has been dissected off of the underlying urothelium and connective tissue. Spontaneous rupture was reported in one of 50 of cases after myectomy in Stohrer's (1997) series.