Yang et al studied the natural history of high risk stigmata in 34 patients with or without injection therapy. They found that, within three or four days, more than one-half of the visible vessels had converted to flat spots or clean-based ulcers, and 90% of all high risk lesions were gone by six days. The only type of lesion that appeared to respond to endoscopic injection therapy was the visible vessel, for which progression to a lower risk lesion was accelerated by approximately half a day. Similarly, almost all adherent clots were gone by three or four days. Because this study found that a small percentage of patients still harboured high risk stigmata at the time of planned discharge (72 h), it appears reasonable to at least consider a predischarge endoscopy.
Nonrandomized trials in this area are difficult to interpret for a few reasons. First, the residual rebleeding rate varies with the baseline clinical and endoscopic factors and the type of medical and endoscopic therapy applied. Therefore, it is difficult to confirm a reduction in this rate compared with a nonrandom or historical control group. Second, patients who undergo repeat endoscopic therapy are often those whom one is most worried about at the initial endoscopy, and have a higher residual rebleeding rate.