Hospitalization for bleeding peptic ulcers has declined over past decades \[1\]. Bleeding from peptic ulcers however remains the commonest diagnosis in those who present with acute upper gastrointestinal bleeding (AUGIB). The incidence has been around 60-80/100,000 population. Endoscopic hemostatic therapy is the first treatment to those with active bleeding and major stigmata of bleeding. Endoscopic therapy stops bleeding and reduces rate of further bleeding, requirement for surgery and importantly deaths \[2\]. Adjunctive intravenous infusion of a high dose proton pump inhibitor (PPI) further reduces rebleeding. In a multicentre international placebo controlled trial that involved 767 patients with bleeding peptic ulcers, a PPI infusion reduced the rate of further bleeding (10.3 to 5.9% at 72 hour, P=0.026) In a subgroup analysis of a Cochrane meta-analysis over use of PPI in bleeding peptic ulcers, the adjunctive use of PPI in those who underwent endoscopic hemostatic treatment, when compared to those without PPI therapy, was associated with a reduction in deaths (17/954 vs. 32/ 969; OR 0.54; 95%CI 0.3-0.96) \[ 4 \] . Despite of aggressive endoscopic therapy and maximal acid suppression using a PPI infusion, further bleeding occurs in around 8% of patients. Further bleeding is the single most important adverse prognostic factor and is associated with a 4 fold increase in mortality. From a National United Kingdom Audit on the management of patients with AUGIB, those who needed surgery for further bleeding and failed endoscopic control had a mortality of 28% \[ 5 \]. In addition to initial control of bleeding with endoscopic therapy, the prevention of further bleeding is an important objective.

The use of routine second look endoscopy with re-treatment has been evaluated in several clinical trials. A recent meta-analysis \[ 6 \] of these clinical trials concluded that the use of routine second look endoscopy confers a modest reduction in rate of further bleeding. In this pooled analysis of 8 trials and 938 patients, the absolute risk reduction was 6.8% (16.5 to 9.7%). The number to treat to prevent one episode of recurrent bleeding was 15. Only one of these trials used high dose PPI infusion and epinephrine injection alone was used as endoscopic treatment. The use of epinephrine injection is no longer considered an optimal treatment. A second modality should be added to induce vessel thrombosis \[ 7 \]. Clinical practice in the reported trials was considered not contemporary. In the modern practice of combination endoscopic treatment and maximal acid suppression, the use of routine second look endoscopy cannot be recommended as the NNT to prevent further bleeding would likely be higher. A policy of routine second look endoscopy is generally not recommended as suggested by an International Consensus Group \[ 8 \].

Second look endoscopy in those at high risk of further bleeding is however a logical approach. The NNT to prevent further bleeding diminishes as risk of further bleeding increases. For instance, an ulcer \> 2 cm in size with Forrest I or Forrest II a bleeding would be associated with a re-bleeding risk of 15-20% even with high dose PPI infusion. Saeed et al. reported a study consisted of a small number of patients (n=40) and showed that endoscopic re-treatment in selected high risk patients based on a Baylor College score led to significant reduction in further bleeding (0 vs. 24%). This selective approach warrants investigation and could represent a dominant strategy in addition to high dose PPI infusion as a pre-emptive management of patients at high risk of further bleeding. A prerequisite to this approach is a risk score that predicts further bleeding in patients after endoscopic hemostasis and PPI infusion. This risk score needs to be derived from a large cohort of patients after uniform endoscopic treatment and acid suppression. The score will have to be validated in a prospective cohort of patients with bleeding peptic ulcers again after the same aggressive treatment. Furthermore, a randomized controlled trial on the use of second look endoscopy in high risk patients as identified by this risk score is required.