***TASK*** the task is to summarize an input biomedical literature in six sentences 
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    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    Input: Controlled trials have shown that bleeding peptic ulcers can be successfully treated by endoscopy and injection of adrenaline , with or without sclerosant . However , these trials have been done in major research centres , and endoscopic treatment of upper gastrointestinal bleeding has not yet become routine in general hospitals . We have done a prospect i ve , r and omised , controlled trial of injection treatment for bleeding peptic ulcers in a district general hospital . Between April , 1989 , and June , 1991 , all patients with acute upper gastrointestinal bleeding ( n = 555 ) underwent endoscopy by an experienced endoscopist within 24 h of admission . 98 patients were found to have an ulcer with a visible vessel , of whom 93 were r and omised to injection ( n = 48 ) or st and ard treatment alone ( n = 45 ) .  Injection treatment consisted of 1 - 2 ml of 1 in 10,000 adrenaline injected at four to six sites around the ulcer . Adrenaline and 5 % ethanolamine oleate ( 1 - 2 ml ) were then injected directly into the vessel . The medical team managing the patient was unaware of the endoscopic treatment given . The two groups were similar for age , initial haemoglobin concentration , shock , and ulcer site . Rebleeding ( injected 8 [ 16.7 % ] vs control 21 [ 46.7 % ] , p = 0.011 ) was significantly reduced in treated patients . The treated group also had lower mortality ( 4 [ 8.3 % ] vs 9 [ 20 % ] ) , requirement for surgery ( 4 [ 8.3 % ] vs 8 [ 17.8 % ] ) , and mean blood-transfusion requirement ( 5 vs 7.5 units ) . Endoscopic injection treatment in our patients significantly reduced rebleeding rate and may have other benefits . This cheap and widely applicable treatment can be used routinely in the management of patients with bleeding peptic ulcers who are at high risk of rebleeding In a r and omized , controlled clinical trial omeprazole was compared with ranitidine plus somatostatin in the treatment of severe acute gastrointestinal bleeding due to peptic pathology . Intravenous infusion of the drugs was administered until clinical stabilization or surgical operation . The two regimens were equally effective in controlling bleeding . The need for blood transfusion and surgical operation together with the mortality rate did not differ significantly between groups . No toxic effects were observed as a result of the infusion of omeprazole . In this study the infusion of omeprazole alone showed an efficacy comparable to the association of ranitidine and somatostatin in the treatment of severe acute peptic bleeding BACKGROUND Does profound acid inhibition by continuous infusion of omeprazole for 72 h reduce further bleeding in elderly patients with peptic ulcer bleeding ( PUB ) ? METHODS Three hundred and thirty-three patients > or = 60 years old with PUB were r and omized to omeprazole ( 80 mg + mg/h ) or placebo as continuous infusion for 72 h. From day 4 to 21 all patients received 20 mg omeprazole orally once daily . RESULTS When evaluated on day 3 , the primary variable ' overall outcome ' ( based on an ordinal ranking scale ; see Study variables ) ( P = 0.017 ) and the secondary variables , surgery ( P = 0.003 ) , degree ( P = 0.004 ) and duration of bleeding ( P = 0.003 ) all favored the omeprazole group . Blood transfusions , need for endoscopic treatment , and mortality were not statistically different . On follow-up , by day 21 , the mortality in the group initially receiving intravenous omeprazole was 6.9 % , while the intravenous placebo group showed an extremely low mortality , 0.6 % . CONCLUSION Three days ' infusion of omeprazole improved overall outcome and reduced need for intervention in PUB patients Twenty four hour intragastric acidity was measured in five duodenal ulcer patients studied at least three times . The effects of different dosage regimens of intravenous omeprazole was compared with placebo .  Mean intragastric acidity from 1000 to 0800 was 34.3 + /- 4.3 mmol/l on placebo . After omeprazole 80 mg at 0900 and 40 mg at 1700 mean acidity was 2.1 + /- 0.9 mmol/l and after omeprazole 80 mg at 0900 and 80 mg at 1700 it was 0.7 + /- 0.2 mmol/l . pH remained above 4.0 for about 80 % of recordings with these regimens and for only 5 % with placebo . Three of the five patients also received omeprazole 80 mg at 0900 , 40 mg at 1700 and 40 mg at 0100 when pH remained above 4.0 for 90 % of recordings with 99 % inhibition of acidity .  Omeprazole rapidly raised intragastric pH in all patients and maintained a gastric pH of greater than 4.0 for most of the time . Large doses of IV omeprazole were required compared with studies using the oral compound Peptic ulcer bleeding often stops spontaneously but rebleeding may be catastrophic . Emergency surgery carries risks so safe medical therapies are needed . Since platelet function and plasma coagulation are both pH sensitive and since pepsin lyses clot at low pH the maintenance of gastric pH close to neutrality might influence rebleeding rates . Previous trials with H2 antagonists have been inadequate although a 1985 meta- analysis did support an important clinical effect . We report here a large multicentre trial of famotidine in ulcer bleeding . 1005 patients admitted to one of sixty-seven hospitals in the UK or Eire with haemorrhage from peptic ulcer with endoscopic signs of oozing , black slough , fresh clot or visible vessel were r and omly allocated to famotidine ( 10 mg bolus followed by 3.2 mg/h intravenously ) or matching placebo for 72 h. This famotidine regimen had previously been shown to maintain pH near 7 in such patients . 497 patients received famotidine and 508 placebo .  The treatment groups were similar in respect of age , sex , ulcer site , and signs and severity of bleeding . Case fatality ( 6.2 % famotidine vs 5.0 % placebo ) , rebleeding ( 23.9 % vs 25.5 % placebo ) , and surgery ( 15.5 % vs 17.1 % placebo ) rates were not significantly different between the two groups . This trial suggests that potent inhibition of gastric secretion does not influence the natural history of peptic ulcer haemorrhage Simultaneous 24-h intragastric and plasma gastrin concentrations were measured in 36 healthy subjects , when receiving placebo ( day 0 ) and on days 1 and 8 of dosing with either placebo ( n = 8) , or  high-dose H2-blockade with either ranitidine 300 mg q.d.s . ( n = 8) , ranitidine 1200 mg o.m . ( n = 8) , or sufotidine 600 mg b.d . ( n = 12 ) . Triplicate placebo studies demonstrated good reproducibility for this technique , with no significant differences of acidity or plasma gastrin concentration between the studies . There was a decrease in the anti-secretory activity of all three high-dose H2-antagonist regimens on day 8 , when compared with that observed on day 1 . This occurred in the presence of sustained or increasing hypergastrinaemia . It is concluded that a degree of tolerance develops during continued H2-blockade , and that this could be due to increasing gastrin drive to the parietal cells BACKGROUND AND STUDY AIMS Although high rates of initial hemostasis can be achieved with endoscopic injection therapy in actively bleeding ulcers , the incidence of rebleeding is not negligible . Optimal conditions for clotting may require achieving deep and sustained acid inhibition to avoid the deleterious effect of acid and pepsin secretions on the hemostatic process . The aim of this study was to assess whether omeprazole could improve the efficacy of ranitidine as an adjunct treatment in endoscopic injection therapy to avoid rebleeding . PATIENTS AND METHODS Eighty-six patients with active arterial bleeding from a peptic ulcer disclosed at emergency endoscopy were included in this prospect i ve trial . All patients received injections of 1:10,000 adrenaline . Subsequently , they were r and omized to receive either intravenous omeprazole ( n = 45 ) , with an initial dose of 80 mg followed by 40 mg every eight hours for four days and thereafter with oral administration ; or ranitidine ( n = 41 ) , 50 mg every six hours for 12 to 24 hours and thereafter with oral administration . RESULTS The two groups were well matched in terms of clinical and endoscopic data . There were no statistically significant differences between the groups with regard to : further bleeding ( 29 % in both groups ) , need for emergency surgery ( 20 % in the omeprazole group vs. 22 % in the ranitidine group ) , transfusion requirements ( 2.4 + /- 2.2 vs. 2.2 + /- 2.1 units ) , length of hospital stay ( 14.1 + /- 13.9 vs. 15.3 + /- 15.4 days ) , or mortality ( 7 % vs. 2 % ) . CONCLUSIONS Our results suggest that omeprazole does not improve the efficacy of ranitidine after endoscopic injection therapy in patients with an active arterial bleeding ulcer We studied the effects of tranexamic acid ( an antifibrinolytic agent ) and cimetidine on acute upper-gastrointestinal-tract bleeding in a double-blind r and omized placebo-controlled trial in 775 patients with hematemesis or melena or both .  Mortality was significantly reduced in patients receiving either tranexamic acid ( mortality , 6.3 per cent ) or cimetidine ( 7.7 per cent ) , as compared with patients receiving placebo ( 13.5 per cent ) ( P = 0.0092 for tranexamic acid vs. placebo , P = 0.045 for cimetidine vs. placebo ) . Ninety-nine patients were withdrawn before the code was broken , mainly because their primary illness was considered not to be due to acute upper-gastrointestinal-tract bleeding .  Mortality among those withdrawn was high ( 22 per cent ) , and their exclusion reduced death rates to 4 per cent in those given tranexamic acid , 8 per cent in those given cimetidine , and 11 per cent in those given placebo ( P = 0.0072 for tranexamic acid vs. placebo , P greater than 0.50 for cimetidine vs. placebo ) . The reduced mortality associated with tranexamic acid was detectable at both participating hospitals and in most of the main subgroups of patients classified according to site of bleeding . However , treatment with this agent was not associated with any decrease in the rate of rebleeding or the need for operation OBJECTIVE --To investigate the possible therapeutic role of omeprazole , a powerful proton pump inhibitor , in unselected patients presenting with upper gastrointestinal bleeding . DESIGN --Double blind placebo controlled parallel group study . Active treatment was omeprazole 80 mg intravenously immediately , then three doses of 40 mg intravenously at eight hourly intervals , then 40 mg orally at 12 hourly intervals . Treatment was started within 12 hours of admission and given for four days or until surgery , discharge , or death . SETTING --The medical wards of University and City Hospitals , Nottingham . SUBJECTS--1147 consecutive patients aged 18 years or more admitted over 40 months with acute upper gastrointestinal bleeding . MAIN OUTCOME MEASURES --Mortality from all causes ; rate of rebleeding , transfusion requirements , and operation rate ; effect of treatment on endoscopic appearances at initial endoscopy . RESULTS --Of 1147 patients included in the intention to treat analysis , 569 received placebo and 578 omeprazole . No significant differences were found between the placebo and omeprazole groups for rates of transfusion ( 302 ( 53 % ) placebo v 298 ( 52 % ) omeprazole ) , rebleeding ( 100 ( 18 % ) v 85 ( 15 % ) ) , operation ( 63 ( 11 % ) v 62 ( 11 % ) ) , and death ( 30 ( 5.3 % ) v 40 ( 6.9 % ) ) . However , there was an unexpected but significant reduction in endoscopic signs of upper gastrointestinal bleeding in patients treated with omeprazole compared with those treated with placebo ( 236 ( 45 % ) placebo v 176 ( 33 % ) omeprazole ; p less than 0.0001 ) . CONCLUSIONS --Omeprazole failed to reduce mortality , rebleeding , or transfusion requirements , although the reduction in endoscopic signs of bleeding suggests that inhibition of acid may be capable of influencing intragastric ble 
    Output:
    
Proton-pump inhibitors may improve outcome in acute peptic ulcer bleeding , but the available clinical data remain inconsistent .