Efficacy of primed infusions with high dose ranitidine and omeprazole to maintain high intragastric pH in patients with peptic ulcer bleeding: a prospective randomised controlled study

Guidelines for the Management of Adult Acute and Acute-on-Chronic Liver Failure in the ICU: Neurology, Peri-Transplant Medicine, Infectious Disease, and Gastroenterology Considerations

OBJECTIVES

To develop evidence-based recommendations for clinicians caring for adults with acute liver failure (ALF) or acute on chronic liver failure (ACLF) in the ICU.

DESIGN

The guideline panel comprised 27 members with expertise in aspects of care of the critically ill patient with liver failure or methodology. We adhered to the Society of Critical Care Medicine standard operating procedures manual and conflict-of-interest policy. Teleconferences and electronic-based discussion among the panel, as well as within subgroups, served as an integral part of the guideline development.

INTERVENTIONS

In part 2 of this guideline, the panel was divided into four subgroups: neurology, peri-transplant, infectious diseases, and gastrointestinal groups. We developed and selected Population, Intervention, Comparison, and Outcomes (PICO) questions according to importance to patients and practicing clinicians. For each PICO question, we conducted a systematic review and meta-analysis where applicable. The quality of evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation approach. We used the evidence to decision framework to facilitate recommendations formulation as strong or conditional. We followed strict criteria to formulate best practice statements.

MEASUREMENTS AND MAIN RESULTS

We report 28 recommendations (from 31 PICO questions) on the management ALF and ACLF in the ICU. Overall, five were strong recommendations, 21 were conditional recommendations, two were best-practice statements, and we were unable to issue a recommendation for five questions due to insufficient evidence.

CONCLUSIONS

Multidisciplinary, international experts formulated evidence-based recommendations for the management ALF and ACLF patients in the ICU, acknowledging that most recommendations were based on low quality and indirect evidence.

Skipping the Drip: Intravenous Proton Pump Inhibitor Bolus Therapy Leads to Poor Outcomes in High-Risk Bleeding

Background and Aim The aim of this study was to evaluate the impact of a change in our institute's protocol from continuous intravenous (IV) proton pump inhibitor (PPI) therapy to bolus IV PPI therapy for the treatment of peptic ulcer-related bleeding on patient outcomes. Current guidelines recommend PPI therapy through high-dose IV bolus followed by continuous infusion for bleeding ulcers. Conflicting data have been reported regarding the practice shift to intermittent IV PPI therapy. Methods A retrospective record review was conducted of patients treated at West Virginia University between 2017 and 2018 for peptic ulcer related bleeding who underwent endoscopy and had high-risk stigmata. Relevant variables were identified. Outcomes were compared between groups based on PPI strategy. The primary endpoint was any poor outcome defined as rebleeding, need for embolization or surgery, or mortality during hospital stay. Results A total of 130 patients were included, with a mean age of 62.18 years. Continuous PPI infusion was used in 39.23%, whereas bolus IV PPI was used 60.76%. Poor outcome was encountered in 11 (21.57%) patients in the continuous and 33 (41.77%) patients in the bolus group (p = 0.028). On multivariable analyses, bolus PPI strategy was independently linked to poor outcome (Wald's odds ratio: 2.8; 95% CI: 1.21-6.84; p = 0.019) and an increased need for embolization/surgery (OR: 4.12, 95% CI: 1.14-19.99; p = 0.046). Conclusions IV bolus therapy showed worse outcomes compared with continuous IV PPI therapy for patients with peptic ulcer bleeding with high-risk features. More robust data are needed before a practice shift to bolus PPI may be appropriate.

Management of acute upper gastrointestinal bleeding: an update for the general physician

Acute upper gastrointestinal bleed (AUGIB) is one of the most common medical emergencies in the UK, with roughly one presentation every 6 min. Despite advances in therapeutics and endoscopy provision, mortality following AUGIB over the last two decades has remained high, with over 9,000 deaths annually in the UK; consequently, several national bodies have published UK-relevant guidelines. Despite this, the 2015 UK National Confidential Enquiry into Patient Outcome and Death in AUGIB highlighted variations in practice, raised concerns regarding suboptimal patient care and released a series of recommendations. This review paper incorporates the latest available evidence and UK-relevant guidelines to summarise the optimal pre-endoscopic, endoscopic, and post-endoscopic approach to and management of non-variceal and variceal AUGIB that will be of practical value to both general physicians and gastroenterologists.

ACVIM consensus statement: Support for rational administration of gastrointestinal protectants to dogs and cats

The gastrointestinal (GI) mucosal barrier is continuously exposed to noxious toxins, reactive oxygen species, microbes, and drugs, leading to the development of inflammatory, erosive, and ultimately ulcerative lesions. This report offers a consensus opinion on the rational administration of GI protectants to dogs and cats, with an emphasis on proton pump inhibitors (PPIs), histamine type-2 receptor antagonists (H2 RAs), misoprostol, and sucralfate. These medications decrease gastric acidity or promote mucosal protective mechanisms, transforming the management of dyspepsia, peptic ulceration, and gastroesophageal reflux disease. In contrast to guidelines that have been established in people for the optimal treatment of gastroduodenal ulcers and gastroesophageal reflux disease, effective clinical dosages of antisecretory drugs have not been well established in the dog and cat to date. Similar to the situation in human medicine, practice of inappropriate prescription of acid suppressants is also commonplace in veterinary medicine. This report challenges the dogma and clinical practice of administering GI protectants for the routine management of gastritis, pancreatitis, hepatic disease, and renal disease in dogs and cats lacking additional risk factors for ulceration or concerns for GI bleeding. Judicious use of acid suppressants is warranted considering recent studies that have documented adverse effects of long-term supplementation of PPIs in people and animals.

Value of Oral Proton Pump Inhibitors in Acute, Nonvariceal Upper Gastrointestinal Bleeding: A Network Meta-Analysis

BACKGROUND

Intravenous (IV) proton pump inhibitors (PPI) are the standard medical treatment in acute nonvariceal upper gastrointestinal bleeding (ANVGIB). Optimal route of PPI delivery has been questioned.

AIM

The aim was to perform a systematic review and network meta-analysis for the endpoints of risk of rebleeding, length of stay (LOS), surgery (ROS), mortality, and total units of blood transfused (UBT) among trials evaluating acid suppressive medications in ANVGIB.

METHODS

A total of 39 studies using IV PPI drip, IV scheduled PPI, oral PPI, H2-receptor antagonists, and placebo were identified. Network meta-analysis was used for indirect comparisons and Bayesian Markov Chain Monte Carlo methods for calculation of probability superiority.

RESULTS

No difference was observed between IV PPI drip and scheduled IV PPI for mortality (relative risk=1.11; 95% credibility interval, 0.56-2.21), LOS (0.04, -0.49 to 0.44), ROS (1.27, 0.64-2.35) and risk of rebleeding within 72 hours, 1 week, and 1 month [(0.98, 0.48-1.95), (0.59, 0.13-2.03), (0.82, 0.28-2.16)]. Oral PPIs were as effective as IV scheduled PPIs and IV PPI drip for LOS (0.22, -0.61 to 0.79 and 0.16, -0.56 to 0.80) and UBT (-0.25, -1.23 to 0.65 and -0.06, -0.71 to 0.65) and superior to IV PPI drip for ROS (0.30, 0.10 to 0.78).

CONCLUSION

Scheduled IV PPIs were as effective as IV PPI drip for most outcomes. Oral PPIs were comparable to scheduled IV for LOS and UBT and superior to IV PPI drip for ROS. Conclusions should be tempered by low frequency endpoints such as ROS, but question the need for IV PPI drip in ANVGIB.

Standard and double-dose intravenous proton pump inhibitor injections for prevention of bleeding after endoscopic resection

BACKGROUND AND AIM

Endoscopic resection is commonly used to remove gastric neoplasms. However, effective dosing or scheduling of proton pump inhibitors for the prevention of delayed bleeding after endoscopic resection remains unclear.

METHODS

One hundred sixty-six patients with gastric adenoma or early gastric cancer were enrolled. After an endoscopic procedure, each subject was randomly assigned to 40 mg every 24 h (standard dose group) or 40 mg every 12 h (double-dose group) of intravenous pantoprazole for 48 h. Second-look endoscopy was performed on day 2 after endoscopic resection to compare signs of rebleeding and ulcer status between the two groups.

RESULT

Eighty-one patients of the standard dose group and 81 of the double-dose group were analyzed. There were no significant differences in the incidence of delayed bleeding events (1.3% vs 6.2%, P = 0.21) and bleeding ulcer at the second-look endoscopy (6.2% vs 3.9%, P = 0.69) between standard and double-dose groups. There were no other significant variables associated with delayed bleeding or bleeding ulcer on second-look endoscopy.

CONCLUSIONS

Intravenous pantoprazole 40 mg every 24 h or 12 h for 2 days after endoscopic resection was equally effective for the prevention of delayed bleeding.

Repeated Famotidine Administration Results in a Diminished Effect on Intragastric pH in Dogs

Background

Famotidine is an acid suppressant commonly administered to dogs. Prolonged famotidine use in people results in decreased efficacy, but the effect in dogs is unknown.

Hypothesis/Objectives

To compare the effect of repeated oral administration of famotidine or placebo on intragastric pH and serum gastrin in dogs. We hypothesized that famotidine would have a diminished effect on intragastric pH on day 13 compared to day 1.

Animals

Six healthy adult colony Beagles.

Methods

Randomized, 2‐factor repeated‐measures crossover design. All dogs received oral placebo or 1.0 mg/kg famotidine q12h for 14 consecutive days. Intragastric pH monitoring was used to continuously record intragastric pH on treatment days 1–2 and 12–13. Mean pH as well as mean percentage time (MPT) that intragastric pH was ≥3 or ≥4 were compared between and within groups by analysis of variance. Serum gastrin was measured on days 0, 3, and 12 for each treatment.

Results

Continued administration of famotidine resulted in a significant decrease in mean pH, MPT ≥3, and MPT ≥4 (P < .0001) on day 12 and 13. This resulted in a mean decrease in pH by 1.63 on days 12 and 13 compared to days 1 and 2. Furthermore, a mean decrease of MPT ≥3 and MPT ≥4 by 33 and 45% was observed for the same time period, respectively.

Conclusions and Clinical Importance

Continued administration of famotidine results in a diminished effect on intragastric pH in dogs. Caution is advised when recommending long‐term, daily oral administration of famotidine to dogs.

Use of proton pump inhibitors in the management of gastroesophageal varices: a systematic review

OBJECTIVE

To review the efficacy and safety of proton pump inhibitors (PPIs) in gastroesophageal varices (GEVs).

DATA SOURCES

MEDLINE (1946 to September 2014), EMBASE (1974 to September 2014), International Pharmaceutical Abstracts (1970 to September 2014), Cochrane Central Register of Controlled Trials (1991 to September 2014), Google, and Google Scholar were searched using the following terms: esophageal varices, gastroesophageal varices, variceal hemorrhage, variceal bleeding, banding ligation, endoscopic variceal ligation, sclerotherapy, proton pump inhibitor, PPI, omeprazole, pantoprazole, lansoprazole, dexlansoprazole, rabeprazole, and esomeprazole.

STUDY SELECTION AND DATA EXTRACTION

Published and unpublished studies evaluating the clinical outcomes of PPI use for GEVs were included regardless of study design. Non-English and nonhuman studies were excluded.

DATA SYNTHESIS

Of 1156 studies, 20 were included after assessment. There was wide methodological heterogeneity and moderately high risk of bias among studies. Level I evidence suggests that PPIs reduce esophageal ulcer size post-elective esophageal ligation; the clinical importance of such findings is not known given the self-limiting nature of esophageal ulcer. Available evidence does not support a role of PPIs for long-term prophylaxis of portal hypertension-related bleeding and high-dose infusion for acute management of GEV hemorrhage. Retrospective data demonstrate a potential increase in the incidence of spontaneous bacterial peritonitis in patients with cirrhosis receiving PPIs.

CONCLUSIONS

The best available evidence supports the use of short-course (10 days) PPI post-endoscopic variceal ligation to reduce ulcer size if ulcer healing is a concern. Practices such as high-dose infusion and prolonged use should be discouraged until evidence of benefit becomes available.

Role of fidaxomicin for the treatment of Clostridium difficile infection

Clostridium difficile is a gram-negative, anaerobic, spore-forming emerging pathogen within health care systems and community-based populations that has a high associated morbidity and mortality as well as cost for the health care system. Recent studies reported high rates of recurrence thus a need for new pharmacological agents to treat C difficile infections (CDIs). Fidaxomicin is a novel macrocyclic antibiotic, originally isolated from fermentation broth of Dactylosporangium aurantiacum spp Hamdenensis, with selective spectrum, unique pharmacokinetic and pharmacodynamics profile, adverse effect profile, efficacy, and role in the treatment of and time to recurrent CDI. Fidaxomicin data have similar clinical cure, when compared to vancomycin, with lower recurrence rates and higher global cure rates in non-BI/NAP1/027 strains. Fidaxomicin also lacks activity against gram-negative bacteria; hence, its potential effect on resistance development among enteric bacteria appears to be low. It appears to have minimal need for renal or hepatic adjustments and minimal concerns for drug-drug interactions. Overall, fidaxomicin has been generally well tolerated with the most common adverse effects reported as mild gastrointestinal complaints. Fidaxomicin appears to have a role in the treatment of CDI with potential lower rates of recurrence, especially in patients with severe disease or risk factors for recurrent CDI.

0.5 mg/kg versus 1 mg/kg of intravenous omeprazole for the prophylaxis of gastrointestinal bleeding in critically ill children: a randomized study

OBJECTIVE

To compare the effect of 2 doses of intravenous omeprazole on gastric pH, gastrointestinal bleeding, and adverse effects in critically ill children.

STUDY DESIGN

We undertook a prospective randomized clinical trial in critically ill children at risk of gastrointestinal bleeding. The effect of 2 intravenous omeprazole regimens (0.5 or 1 mg/kg every 12 hours) on the gastric pH and incidence of gastrointestinal hemorrhage was compared. The efficacy criteria were a gastric pH >4 and the absence of clinically significant gastrointestinal bleeding.

RESULTS

Forty patients, 20 in each treatment group, were studied. Overall, the gastric pH was greater than 4 for 57.8% of the time, with no difference between the doses (P = .66). The percentage of time with a gastric pH > 4 increased during the study (47.8% between 0 and 24 hours vs 76% between 24 and 48 hours, P = .001); the greater dose showed a greater increase in the percentage of time with a pH > 4: between hours 24 and 48 of the study, the gastric pH was greater than 4 for 84.5% of the time with the 1 mg/kg dose and for 65.5% of the time with the 0.5 mg/kg dose (P = .036). Plasma omeprazole levels were greater with 1 mg/kg dose, but no correlation was found between omeprazole plasma levels and gastric pH. No toxic adverse effects were detected, and there was no clinically significant bleeding.

CONCLUSION

Neither of the 2 omeprazole regimens achieved adequate alkalinization of the gastric pH during the first 24 hours. Between 24 and 48 hours, the 1 mg/kg dose maintained the gastric pH greater than 4 for a greater percentage of the time.

Fidaxomicin: a macrocyclic antibiotic for the treatment of Clostridium difficile infection

Clostridium difficile is an emerging pathogen in certain health care systems and community-based populations that is associated with high rates of morbidity and mortality, as well as increased costs for the health care system. As recurrence rates increase, new pharmacologic agents to treat C. difficile infection are needed. Fidaxomicin, a novel macrocyclic antibiotic, was recently approved by the United States Food and Drug Administration for the treatment of C. difficile-associated diarrhea. Originally isolated from fermentation broth of Dactylosporangium aurantiacum subspecies hamdenensis, the drug has a selective spectrum, distinctive pharmacokinetic and pharmaco-dynamic properties, and a favorable adverse-effect profile. Fidaxomicin has demonstrated similar clinical cure rates (i.e., resolution of diarrhea) compared with vancomycin, with lower recurrence rates and higher global cure rates (i.e., resolution of diarrhea without recurrence) in non-restriction endonuclease analysis type BI, North American Pulsed Field type 1 (NAP1), polymerase chain reaction ribotype 027 (or non-BI/NAP1/027) strains. Overall, fidaxomicin has been generally well tolerated, with the most common adverse effects reported as mild gastrointestinal complaints. Fidaxomicin appears to be a useful agent in the treatment of severe C. difficile infection, demonstrating decreased rates of recurrence.

Meta-analysis: comparative efficacy of H2-receptor antagonists and proton pump inhibitors for reducing aspiration risk during anaesthesia depending on the administration route and schedule

H2-receptor antagonists (H2RA) and proton pump inhibitors (PPI) are widely used for aspiration prophylaxis in patients receiving general anaesthesia. Many randomized trials have compared these agents but it remains unclear which drug type is more effective in reducing the number of patients at risk of complications. The study aimed to compare their efficacy for decreasing the number of patients at risk of acid aspiration during general anaesthesia. Major databases were systematically searched. Randomized controlled trials comparing PPI and H2RA were selected. Sub-analyses were performed considering the dose, the dosing schedule, and the route of administration. Eighteen studies fulfilled the inclusion criteria. The main analysis showed a non-significant trend for H2RA being more effective than PPI. Only when both drugs were administered per os, as a single dose and immediately before surgery, was H2RA significantly more effective than PPI. By contrast, the effect of PPI and H2RA was similar when they were administered in two doses (the night before and on the morning of surgery) or when the drugs were given intravenously. A single H2RA dose before surgery is highly effective in reducing the number of patients at risk of acid aspiration. PPI administered in two oral doses or in a single intravenous infusion seems to be as effective as H2RA.

Proton Pump Inhibitor Therapy before and after Endoscopic Submucosal Dissection: A Review

Endoscopic submucosal dissection (ESD) is a novel endoscopic procedure first developed in the 1990s which enables en bloc resection of gastric neoplastic lesions that are difficult to resect via conventional endoscopic mucosal resection. However, given that ESD increases the risk of intra- and post-ESD delayed bleeding and that platelet aggregation and coagulation in artificial ulcers after ESD strongly depend on intragastric pH, faster and stronger acid inhibition via proton pump inhibitors (PPIs) and histamine 2-receptor antagonists (H(2)RAs) as well as endoscopic hemostasis by thermocoagulation during ESD have been used to prevent ESD-related bleeding. Because PPIs more potently inhibit acid secretion than H(2)RAs, they are often the first-line drugs employed in ESD treatment. However, acid inhibition after the initial infusion of a PPI is weaker in the early phase than that achievable with H(2)RAs; further, PPI effectiveness can vary depending on genetic differences in CYP2C19. Therefore, optimal acid inhibition may require tailored treatment based on CYP2C19 genotype when ESD is performed, with a concomitant infusion of PPI and H(2)RA possibly most effective for patients with the rapid metabolizer CYP2C19 genotype, while PPI alone may be sufficient for those with the intermediate or poor metabolizer genotypes.

PREDICTING EFFICACY OF PROTON PUMP INHIBITORS IN REGULATING GASTRIC ACID SECRETION

Developing drugs to treat gastric acid related illnesses such as ulcers and acid reflux disease is the leading focus of pharmaceutical companies. In fact, expenditure for treating these disorders is highest among all illnesses in the US. Over the last few decades, a class of drugs known as a proton pump inhibitors (PPIs) appeared on the market and are highly effective at abating gastric illnesses by raising stomach pH (reducing gastric acid levels). While much is known about the action of PPIs , there are still open questions regarding their efficacy, dosing and long-term effects. Here we extend a previous gastric acid secretion model developed by our group to incorporate a pharmacodynamic/pharmacokinetic model to study proton pump inhibitor (PPI) action. Model-relevant parameters for specific drugs such as omeprazole (OPZ) , lansoprazole (LPZ) and pantoprazole (PPZ) were used from published data, and we conducted simulations to study various aspects of PPI treatment. Clinical data suggests that duration of acid suppression is dependent on proton pump turnover rates and this is supported by our model. We found the order of efficacy of the different PPIs to be OPZ>PPZ>LPZ for clinically recommended dose values, and OPZ>PPZ=LPZ for equal doses. Our results indicate that a breakfast dose for once-daily dosing regimens and a breakfast-lunch dose for twice-daily dosing regimens is recommended. Simulation of other gastric disorders using our model provides atypical applications for the study of drug treatment on homeostatic systems and identification of potential side-effects.

Pharmacologic treatment of peptic ulcer bleeding

Over the last 3 decades, there has been extensive clinical research on the pharmacologic treatment of peptic ulcer bleeding. A critical review of randomized controlled trials and meta-analyses reveals insufficient evidence to recommend histamine-2 receptor antagonists (H(2)RAs), somatostatin, octreotide, or tranexamic acid in the routine management of patients with peptic ulcer bleeding. In contrast, there is good-quality evidence for recommending proton-pump inhibitor (PPI) treatment for patients with peptic ulcer bleeding. PPI treatment, compared with an H(2)RA or placebo, reduces rebleeding and the need for surgical intervention and, in patients with high-risk endoscopic stigmata, also reduces all-cause mortality. Patients with ulcers that demonstrate only low-risk endoscopic stigmata (clean base or flat pigmented spot) can be treated with an oral PPI at double the standard clinical dose. Patients with ulcers that demonstrate high-risk endoscopic stigmata (spurting, oozing, or nonbleeding visible vessel) should receive high-dose intravenous PPI treatment following appropriate endoscopic hemostatic treatment. The currently recommended dose is an initial intravenous bolus equivalent to 80 mg of omeprazole followed by an intravenous infusion equivalent to 8.0 mg/h of omeprazole for up to 72 hours. A switch to high-dose oral PPI treatment may be appropriate before completion of a 72-hour treatment period in some patients whose clinical status stabilizes early. Once the initial bleeding episode has been dealt with, patients will require standard pharmacologic treatment to heal the ulcer and prevent recurrence.

Intravenous proton pump inhibitors for peptic ulcer bleeding: Clinical benefits and limits

Peptic ulcer bleeding is a common disease and recurrent bleeding is an independent risk factor of mortality. Infusion with proton pump inhibitors (PPIs) prevents recurrent bleeding after successful endoscopic therapy. A gastric acidic environment of less than pH 5.4 alters coagulation function and activates pepsin to disaggregate platelet plugs. Gastric acid is secreted by H⁺, K⁺-ATPase, naming the proton pump. This update review focuses on the mechanism and the role of PPIs in the clinical management of patients with peptic ulcer bleeding. An intravenous omeprazole bolus followed by high-dose continuous infusion for 72 h after successful endoscopic therapy can prevent the recurrent bleeding. In the Asian, however, the infusion dosage can possibly be diminished whilst preserving favorable control of the intragastric pH and thereby still decreasing rates of recurrent bleeding. Irrespective of the infusion dosage of PPIs, rates of recurrent bleeding remain high in patients with co-morbidities. Because recurrent peptic ulcer bleeding may be prolonged in those with co-morbidities, a low-dose infusion of IV PPIs for up to 7-day may result in better control of recurrent bleeding of peptic ulcers. Due to the inter-patient variability in CYP2C19 genotypes, the infusion form of new generation PPIs, such as esomeprazole, should be promising for the prevention of recurrent bleeding. This article offers a comprehensive review of clinical practice, highlighting the indication, the optimal dosage, the duration, and the potential limitation of PPIs infusion for peptic ulcer bleeding.

Randomized controlled trial of standard versus high-dose intravenous omeprazole after endoscopic therapy in high-risk patients with acute peptic ulcer bleeding

Background

Rebleeding from peptic ulcers is a major contributor to death. This study compared standard (40-mg intravenous infusion of omeprazole once daily for 3 days) and high-dose (80-mg bolus of omeprazole followed by 8-mg/h infusion for 72 h) in reducing the rebleeding rate (primary endpoint), need for surgery, duration of hospital stay and mortality in patients with peptic ulcer bleeding after successful endoscopic therapy.

Methods

This was a single-institution prospective randomized controlled study based on a postulated therapeutic equivalence of the two treatments. All patients who had successful endoscopic haemostasis of a bleeding peptic ulcer (Forrest classification Ia, Ib, IIa or IIb) were recruited. Informed consent was obtained and patients were randomized to receive standard- or high-dose infusions of intravenous omeprazole.

Results

Two (3 per cent) of 61 patients in the high-dose group and ten (16 per cent) of 61 in the standard-dose group exhibited rebleeding, a difference of − 13 (95 per cent confidence interval − 25 to − 2) per cent. The upper limit of the one-sided confidence interval exceeded a predefined equivalence absolute difference of 16 per cent. Equivalence of standard- and high-dose omeprazole in preventing rebleeding was not demonstrated.

Conclusion

Intravenous standard-dose omeprazole was inferior to high-dose omeprazole in preventing rebleeding after endoscopic haemostasis for peptic ulcer bleeding. Registration number: NCT00519519 (http://www.clinicaltrials.gov).

Esomeprazole for the treatment of peptic ulcer bleeding

Peptic ulcer bleeding is the most common cause of acute bleeding in the upper GI tract. The incidence of peptic ulcer bleeding has slowly decreased and endoscopic treatment options have improved; nevertheless, it remains a very common condition with a 7-15% mortality. Acidic environments have a negative effect on hemostasis. Therefore, acid inhibitors have been applied in the adjuvant treatment of peptic ulcer bleeding, both in preventing rebleeding and in treating the underlying cause. This requires profound acid suppressive therapy aiming for a rapid onset of effect and a persistent intragastric pH above 6. This can only be achieved by proton pump inhibitors (PPIs). Esomeprazole is the S-isomer of omeprazole, and the first PPI to consist of only the active isomer. A number of studies have compared esomeprazole with other PPIs, demonstrating a faster and more persistent increase in intragastric pH with the use of esomeprazole than with other agents. Continuous high-dose intravenous treatment with esomeprazole decreases rebleeding, surgery, transfusion rates and hospital days in peptic ulcer bleeding.

Reversal of the tolerance phenomenon by the intermittent administration of a histamine H2-receptor antagonist

BACKGROUND AND AIM

The attenuated antisecretory activity of H2-receptor antagonists (H2RA) during continuous administration is referred to as the tolerance phenomenon. A previous study indicated that Helicobacter pylori (H. pylori) infection prevents the occurrence of tolerance to H2RA. In the present study, we investigated whether intermittent (every other day) administration prevents the tolerance phenomenon in H. pylori-negative patients.

METHODS

Ten H. pylori-negative, healthy volunteers were included in the study. All of the patients underwent two courses of H2RA (lafutidine) administration: 21-day continuous administration (every day), followed by 21-day intermittent administration (every other day), with at least a 21-day lafutidine-free period between the first and second courses. All of the patients were examined by ambulatory intragastric pH monitoring five times: before medication, and on days 1 and 21 of the first (continuous) and second (intermittent) courses of lafutidine (10 mg b.d.) in a crossover fashion.

RESULTS

The continuous administration of lafutidine had a significantly attenuated, acid-suppressing effect in H. pylori-negative patients, and showed evidence of the tolerance phenomenon. However, the tolerance phenomenon was not observed through intermittent administration.

CONCLUSIONS

These results demonstrated that in H. pylori-negative patients, tolerance to H2RA, induced by continuous lafutidine administration, was reversed by subsequent intermittent administration.

WITHDRAWN: Proton pump inhibitor treatment for acute peptic ulcer bleeding

BACKGROUND

Randomised controlled trials (RCTs) evaluating the clinical effect of proton pump inhibitors (PPIs) in peptic ulcer (PU) bleeding yield conflicting results.

OBJECTIVES

To evaluate the efficacy of PPIs in acute bleeding from PU using evidence from RCTs.

SEARCH STRATEGY

We searched CENTRAL, The Cochrane Library (Issue 4, 2004), MEDLINE (1966 to November 2004), EMBASE (1980 to November 2004), proceedings of major meetings to November 2004, and reference lists of articles. We contacted pharmaceutical companies and experts in the field.

SELECTION CRITERIA

RCTs of PPI treatment (oral or intravenous) compared with placebo or H(2)-receptor antagonist (H(2)RA) in acute bleeding from PU.

DATA COLLECTION AND ANALYSIS

Two reviewers extracted data independently, assessed study validity, summarised studies and undertook meta-analysis. The influence of study characteristics on the outcomes was examined by subgroup analyses and meta-regression.

MAIN RESULTS

Twenty-four RCTs comprising 4373 participants in total were included. Statistical heterogeneity was found among trials for rebleeding (P = 0.04), but not for all-cause mortality (P = 0.24) or surgery (P = 0.45). There was no significant difference in all-cause mortality rates between PPI and control treatment; pooled rates were 3.9% on PPI versus 3.8% on control (odds ratio (OR) 1.01; 95% CI 0.74 to 1.40). PPIs significantly reduced rebleeding compared to control; pooled rates were 10.6% with PPI versus 17.3% with control treatment (OR 0.49; 95% CI 0.37 to 0.65). PPI treatment significantly reduced surgery compared with control; pooled rates were 6.1% on PPI versus 9.3% on control (OR 0.61; 95% CI 0.48 to 0.78). There was no evidence to suggest that results on mortality and rebleeding were dependent on study quality, route of PPI administration, type of control treatment or application of initial endoscopic haemostatic treatment. PPIs significantly reduced surgery compared with placebo but not when compared with H(2)RA. There was no evidence to suggest that study quality, route of PPI administration or application of initial endoscopic haemostatic treatment influenced results on surgery. PPI treatment appeared more efficacious in studies conducted in Asia compared to studies conducted elsewhere. All-cause mortality was reduced only in Asian studies; reductions in rebleeding and surgery were quantitatively greater in Asian studies. Among patients with active bleeding or non-bleeding visible vessel, PPI treatment reduced mortality (OR 0.53; 95% CI 0.31 to 0.91), rebleeding and surgery.

AUTHORS' CONCLUSIONS

PPI treatment in PU bleeding reduces rebleeding and surgery compared with placebo or H(2)RA, but there is no evidence of an overall effect on all-cause mortality.

Gastric acid inhibition in the treatment of peptic ulcer hemorrhage

Upper gastrointestinal bleeding from peptic ulcer disease is a common clinical event, resulting in considerable patient morbidity and significant health care costs. Inhibiting gastric acid secretion is a key component in improving clinical outcomes, including reducing rebleeding, transfusion requirements, and surgery. Raising intragastric pH promotes clot stability and reduces the influences of gastric acid and pepsin. Patients with high-risk stigmata for ulcer bleeding (arterial bleeding, nonbleeding visible vessels, and adherent clots) benefit significantly from and should receive high-dose intravenous proton pump inhibitors (PPIs) after successful endoscopic hemostasis. For patients with low-risk stigmata (flat spots or clean ulcer base), oral PPI therapy alone is sufficient. For oozing bleeding (an intermediate risk finding), successful endoscopic hemostasis and oral PPI are recommended. Using intravenous PPIs before endoscopy appears to reduce the frequency of finding high-risk stigmata on later endoscopy, but has not been shown to improve clinical outcomes. High-dose oral PPIs may be as effective as intravenous infusion in achieving positive clinical outcomes, but this has not been documented by randomized studies and its cost-effectiveness is unclear.

How evidence-based are current guidelines for managing patients with peptic ulcer bleeding?

Current guidelines for managing ulcer bleeding state that patients with major stigmata should be managed by dual endoscopic therapy (injection with epinephrine plus a thermal or mechanical modality) followed by a high dose intravenous infusion of proton pump inhibitors (PPIs). This paper aims to review and critically evaluate evidence supporting the purported superiority of a continuous infusion over less intensive regimens of PPIs administration and the need for adding a second hemostatic endoscopic procedure to epinephrine injection. Systematic searches of PubMed, EMBASE and the Cochrane library were performed. There is strong evidence for an incremental benefit of PPIs over H2-receptor antagonists or placebo for the outcome of patients with peptic ulcer bleeding following endoscopic hemostasis. However, the benefit of PPIs is unrelated to either the dosage (intensive vs standard regimen) or the route of administration (intravenous vs oral). There is significant heterogeneity among the 15 studies that compared epinephrine with epinephrine plus a second modality, which might preclude the validity of reported summary estimates. Studies without second look endoscopy plus re-treatment of re-bleeding lesions showed a significant benefit of adding a second endoscopic modality for hemostasis, while studies with second-look and re-treatment showed equal efficacy between endoscopic mono and dual therapy. Inconclusive experimental evidence supports the current recommendation of the use of dual endoscopic hemostatic means and infusion of high-dose PPIs as standard therapy for patients with bleeding peptic ulcers. Presently, the combination of epinephrine monotherapy with standard doses of PPIs constitutes an appropriate treatment for the majority of patients.

Effect of oral lansoprazole on intragastric pH after endoscopic treatment for bleeding peptic ulcer

OBJECTIVE

Intravenous proton pump inhibitors (PPIs) induce a high intragastric pH and may thereby improve haemostasis in patients with bleeding peptic ulcer. The aim of this study was to investigate whether a similar therapeutic intragastric pH level could be reached when the PPI was administered orally.

MATERIAL AND METHODS

Twenty-four-hour intragastric pH was measured in patients treated endoscopically for bleeding peptic ulcer (Forrest class I or II). The patients received lansoprazole capsules (90 mg) after successful endoscopic treatment, followed by 30 mg every third hour for 72 h. The primary end-point was the percentage of the 0 to 24-h registration period with an intragastric pH of 6 or higher. Additionally, the total number of patients obtaining an intragastric pH above 6 for 80% or more of the 0 to 24-h period after start of treatment was evaluated.

RESULTS

Of the 14 patients included in the study (4 F, mean age 74 years, range 50-84 years), 10 patients had duodenal ulcer and 4 had gastric ulcer; median lowest Hgb: 8.9 mg/ml (range 5.8-12.4), blood transfusions: 2.7 SAG units (range 0-7). In the 0 to 24-h period, the median time duration of pH above 6 was 55% (range 6-99). One out of 14 patients (7%) reached a pH above 6 in at least 80% of this time period.

CONCLUSIONS

An increase in intragastric pH of therapeutic importance was reached with this oral medication regimen. However, there were large intra-individual differences. Treatment with oral lansoprazole may be a therapeutic alternative to intravenous administration of PPI.

Management of upper gastrointestinal bleeding

Upper gastrointestinal bleeding secondary to ulcer disease is common and results in substantial patient morbidity and medical expense. After initial resuscitation to stabilize the patient, carefully performed endoscopy provides an accurate diagnosis and identifies high-risk ulcer patients who are likely to rebleed with medical therapy alone and will benefit most from endoscopic hemostasis. For patients with major stigmata of ulcer hemorrhage--active arterial bleeding, nonbleeding visible vessel, and adherent clot--combination therapy with epinephrine injection and either thermal coagulation (multipolar or heater probe) or endoclips is recommended. High-dose intravenous proton pump inhibitors are recommended as concomitant therapy after successful endoscopic hemostasis. Patients with minor stigmata or clean-based ulcers will not benefit from endoscopic treatment and should receive high-dose oral proton pump inhibitor therapy. Effective medical and endoscopic management of ulcer hemorrhage can significantly improve outcomes and decrease the cost of medical care by reducing rebleeding, transfusion requirements, and the need for surgery.

High- versus low-dose proton pump inhibitors after endoscopic hemostasis in patients with peptic ulcer bleeding: a multicentre, randomized study

BACKGROUND

The most effective schedule of proton pump inhibitor (PPI) administration following endoscopic hemostasis of bleeding ulcers remains uncertain.

METHODS

Patients with actively bleeding ulcers and those with nonbleeding visible vessel or adherent clot were treated with epinephrine injection and/or thermal coagulation, and randomized to receive intravenous PPIs according to an intensive regimen (80 mg bolus followed by 8 mg/h as continuous infusion for 72 h) or a standard regimen (40 mg bolus daily followed by saline infusion for 72 h). After the infusion, all patients were given 20 mg PPI twice daily orally. The primary end point was the in-hospital rebleeding rate, as ascertained at the repeat endoscopy.

RESULTS

Bleeding recurred in 28 of 238 patients (11.8%) receiving the intensive regimen, and in 19 of 236 (8.1%) patients receiving the standard regimen (P= 0.18). Most rebleeding episodes occurred during the initial 72-h infusion: 18 (7.6%) and 19 events (8.1%) in the intensive and standard groups, respectively (P= 0.32). Mean units of blood transfused were 1.7 +/- 2.1 in the intensive and 1.5 +/- 2.1 in the standard regimen group (P= 0.34). The duration of hospital stay was <5 days for 88 (37.0%) and 111 patients (47.0%) in the intensive and standard groups (P= 0.03). There were fewer surgical interventions in the standard versus intensive regimen (1 vs 3). Five patients in each treatment group died.

CONCLUSIONS

Following endoscopic hemostasis of bleeding ulcers, standard-dose PPIs infusion was as effective as a high-dose regimen in reducing the risk of recurrent bleeding. (ClinicalTrials.gov number, NCT00374101).

Stress-related mucosal bleeding in critically ill oncology patients

Objective. To determine the incidence of stress-related mucosal bleeding (SRMB) in a critically ill oncology population receiving stress ulcer prophylaxis (SUP) with either a histamine-2 receptor antagonist (H2RA) or proton pump inhibitor (PPI). Design. Single-center, prospective, observational study.

Setting. Fifty-two bed medical-surgical intensive care unit of an academic oncology institution. Patients. A convenience sample of 100 medical and surgical critically ill oncology patients who received intensive care for more than 24 hours and at least one dose of a H2RA or PPI for prevention of SRMB.

Interventions. None.

Measurements and Main Results. Patients were followed throughout their intensive care unit stay for the development of an overt and/or clinically significant gastrointestinal (GI) bleed. More patients received a PPI (n = 81) in contrast to a H2RA (n = 19) for SUP. Overall, 94 patients (94%) had at least one risk factor for a SRMB with four patients (4%) experiencing an event (overt bleed, n=3; clinically significant bleed, n =1). All cases of GI bleeding occurred in patients receiving a PPI. No ICU deaths were considered directly related to a GI bleed.

Conclusions. The incidence of SRMB among high-risk critically ill oncology patients receiving SUP appears low; further, large-scale trials are needed to confirm this finding. J Oncol Pharm Practice (2009) 15: 9—16.

Intragastric pH with oral vs intravenous bolus plus infusion proton-pump inhibitor therapy in patients with bleeding ulcers

BACKGROUND & AIMS

Intravenous bolus plus infusion proton pump inhibitor (PPI) therapy is recommended for patients with bleeding ulcers and higher risk stigmata. If frequent oral dosing of PPIs provided similar antisecretory effect, this might be preferred based on ease and cost.

METHODS

Patients presenting with overt bleeding due to ulcers had intragastric pH probes placed after endoscopy and baseline pH recorded. They were randomly assigned to intravenous lansoprazole (90-mg bolus followed by 9-mg/h infusion) or oral lansoprazole (120-mg bolus followed by 30 mg every 3 hours). pH was recorded for 24 hours.

RESULTS

Intragastric pH was > 6 for 67.8% of the study period with intravenous PPI (n = 32) and 64.8% with oral PPI (n = 34): difference, 3.0%; 95% confidence interval (CI): -9.2% to 15.2%. Intragastric pH was > 6 for > 60% of the study period in 22 (68.8%) patients receiving intravenous and 22 (64.7%) patients receiving oral PPI: difference, 4.0%; 95% CI: -18.7% to 26.8%. At 1 hour, mean pHs for intravenous vs oral were 5.3 +/- 0.4 vs 3.3 +/- 0.4, respectively (difference, 2.0; 95% CI: 0.8-3.1; P = .001). At > or = 1.5 hours, 95% CIs of the differences for all hourly mean pHs included zero. Mean pH rose above 6 after 2-3 hours of intravenous PPI and 3-4 hours of oral PPI.

CONCLUSIONS

Frequent oral PPI may be able to replace the currently recommended intravenous bolus plus infusion PPI therapy in patients with bleeding ulcers, although the possibility that intravenous PPIs are superior cannot be definitively excluded given our relatively wide confidence intervals. Intravenous PPI provides more rapid increase in pH, reaching mean pH of 6 approximately 1 hour sooner than oral PPI.

Intravenous esomeprazole for prevention of peptic ulcer re-bleeding: rationale/design of Peptic Ulcer Bleed study

BACKGROUND

A limited number of trials have investigated the efficacy of proton pump inhibitors for peptic ulcer bleeding, and some study design issues have been identified.

AIM

To present the design of a large trial evaluating the effects of intravenous esomeprazole on clinical outcomes in high-risk patients who have undergone endoscopic haemostasis for peptic ulcer bleeding.

METHODS

The Peptic Ulcer Bleed study is an international, randomized, double-blind, placebo-controlled trial comparing either esomeprazole 80 mg intravenous bolus infusion for 30 min followed by esomeprazole 8 mg/h intravenously for 71.5 h, or placebo infusion for 72 h, after successful endoscopic haemostasis in patients with peptic ulcer bleeding and associated high-risk stigmata. All patients will receive once daily oral esomeprazole 40 mg for 27 days after intravenous therapy. The primary end point is the rate of clinically significant re-bleeding during the first 72 h after endoscopy. Secondary end points include: rate of re-bleeding during the first 7 and 30 days after treatment; length of hospitalization; mortality; blood transfusion; endoscopic re-treatment and surgery.

RESULTS

Expected 2008.

CONCLUSIONS

The carefully designed protocol and quality control measures represent a pragmatic approach to contemporary challenges in peptic ulcer bleeding management and, it is hoped, qualify the Peptic Ulcer Bleed study as a new standard for future interventional studies.

Omeprazole before endoscopy in patients with gastrointestinal bleeding

BACKGROUND

A neutral gastric pH is critical for the stability of clots over bleeding arteries. We investigated the effect of preemptive infusion of omeprazole before endoscopy on the need for endoscopic therapy.

METHODS

Consecutive patients admitted with upper gastrointestinal bleeding underwent stabilization and were then randomly assigned to receive either omeprazole or placebo (each as an 80-mg intravenous bolus followed by an 8-mg infusion per hour) before endoscopy the next morning.

RESULTS

Over a 17-month period, 638 patients were enrolled and randomly assigned to omeprazole or placebo (319 in each group). The need for endoscopic treatment was lower in the omeprazole group than in the placebo group (60 of the 314 patients included in the analysis [19.1%] vs. 90 of 317 patients [28.4%], P=0.007). There were no significant differences between the omeprazole group and the placebo group in the mean amount of blood transfused (1.54 and 1.88 units, respectively; P=0.12) or the number of patients who had recurrent bleeding (11 and 8, P=0.49), who underwent emergency surgery (3 and 4, P=1.00), or who died within 30 days (8 and 7, P=0.78). The hospital stay was less than 3 days in 60.5% of patients in the omeprazole group, as compared with 49.2% in the placebo group (P=0.005). On endoscopy, fewer patients in the omeprazole group had actively bleeding ulcers (12 of 187, vs. 28 of 190 in the placebo group; P=0.01) and more omeprazole-treated patients had ulcers with clean bases (120 vs. 90, P=0.001).

CONCLUSIONS

Infusion of high-dose omeprazole before endoscopy accelerated the resolution of signs of bleeding in ulcers and reduced the need for endoscopic therapy. (ClinicalTrials.gov number, NCT00164866 [ClinicalTrials.gov] .).

Continuous infusion of high-dose omeprazole is more effective than standard-dose omeprazole in patients with high-risk peptic ulcer bleeding: a retrospective study

High-dose omeprazole reduces the rate of recurrent bleeding after endoscopic treatment of peptic ulcer bleeding. However, the effectiveness of high-dose vs. standard-dose omeprazole in peptic ulcer bleeding has never been shown.

AIM

To compare the benefits of high-dose vs. standard-dose omeprazole in peptic ulcer bleeding.

METHODS

We reviewed the medical files of patients admitted between 1997 and 2004 for high-risk peptic ulcer bleeding who had undergone successful endoscopic treatment. We distinguished 2 periods: before 2001, standard-dose omeprazole (40 mg/day intravenously until alimentation was possible, then 40 mg/day orally for 1 week); after 2001, high-dose omeprazole (80 mg bolus injection, then 8 mg/h continuous infusion for 72 h, then 40 mg/day orally for 1 week). During both periods, patients subsequently received omeprazole, 20 mg/day, orally for 3 weeks.

RESULTS

We enrolled 114 patients (period 1, n = 45, period 2, n = 69). Therapy with high-dose omeprazole significantly decreased the occurrence of poor outcome (27 vs. 12%, P = 0.04), rebleeding (24 vs. 7%, P = 0.01), mortality due to haemorrhagic shock (11 vs. 0%, P < 0.001) and need for surgery (9 vs. 1%, P = 0.05).

CONCLUSIONS

In this retrospective study, high-dose omeprazole reduced the occurrence of rebleeding, need for surgery and mortality due to hemorrhagic shock in patients with high-risk peptic ulcer bleeding, as compared with standard-dose omeprazole.

Proton pump inhibitor therapy for peptic ulcer bleeding: Cochrane collaboration meta-analysis of randomized controlled trials

OBJECTIVE

To evaluate the efficacy of proton pump inhibitors (PPIs) in treating peptic ulcer bleeding.

MATERIAL AND METHODS

We searched the MEDLINE, EMBASE, CENTRAL, Cochrane Library, and metaRegister of Controlled Trials databases and published proceedings of major meetings through November 2004 for randomized controlled trials that compared oral or intravenous PPIs with placebo or a histamine2-receptor antagonist for peptic ulcer bleeding. Pharmaceutical companies and relevant experts were contacted. Data extraction and assessment of study validity were performed independently in duplicate. Assessed outcomes were 30-day all-cause mortality, rebleeding, surgery, and repeated endoscopic treatment. Influence of study characteristics on outcomes was examined by subgroup analyses and meta-regression.

RESULTS

We included 24 trials (4373 participants). Statistical heterogeneity was evident only for rebleeding. Treatment with PPIs had no significant effect on mortality (odds ratio [OR], 1.01; 95% confidence interval [CI], 0.74-1.40; number needed to treat [NNT], incalculable) but significantly reduced rebleeding (OR, 0.49; 95% CI, 0.37-0.65; NNT, 13) and the need for surgery (OR, 0.61; 95% CI, 0.48-0.78; NNT, 34) and repeated endoscopic treatment (OR, 0.32; 95% CI, 0.20-0.51; NNT, 10). Results were similar when analysis was confined to trials with adequate allocation concealment. Treatment with PPIs significantly reduced mortality in Asian trials (OR, 0.35; 95% CI, 0.16-0.74; NNT, 34) and in patients with active bleeding or a nonbleeding visible vessel (OR, 0.53; 95% CI, 0.31-0.91; NNT, 50).

CONCLUSIONS

In ulcer bleeding, PPIs reduce rebleeding and the need for surgery and repeated endoscopic treatment. They improve mortality among patients at highest risk.

Effect of oral esomeprazole on recurrent bleeding after endoscopic treatment of bleeding peptic ulcers

BACKGROUND

After endoscopic treatment of bleeding peptic ulcer, a high-dose infusion of omeprazole substantially reduces the risk of recurrent bleeding. The role of oral proton pump inhibitors for these patients is uncertain. The purpose of the present study was to assess whether the use of oral esomeprazole would reduce the frequency of recurrent bleeding after endoscopic treatment of bleeding peptic ulcers.

METHODS

Patients with actively bleeding ulcers or ulcers with non-bleeding visible vessels were treated with an epinephrine injection followed by thermocoagulation. After hemostasis had been achieved, they were randomly assigned in a double-blind fashion to receive esomeprazole (40 mg p.o. twice daily for 3 days) or placebo. The outcome measures studied were recurrent bleeding, blood transfusion requirement, surgery and death.

RESULTS

A total of 70 patients were enrolled, 35 in each group. Bleeding recurred within 30 days in two patients (5.7%) in the esomeprazole group, as compared with three (8.6%) in the placebo group (P = 0.999). Blood transfusion requirement was 2.8 +/- 1.4 units in the esomeprazole group and 2.7 +/- 1.3 units in the placebo group (P = 0.761). Duration of hospitalization was 4.82 +/- 1.8 days in the esomeprazole group and 4.58 +/- 2.7 days in the placebo group (P = 0.792). No patients needed surgery for control of bleeding and no patients died in both groups.

CONCLUSIONS

After successful endoscopic treatment of bleeding peptic ulcer, oral use of esomeprazole might offer no additional benefit on the risk of recurrent bleeding.

Some Observations on PPI Therapy for Bleeding Ulcer

Proton pump inhibitor (PPI) therapy improves some outcomes after peptic ulcer bleeding. Recent meta-analyses have consistently found reduced rates of rebleeding and surgical intervention but there has been some discordance about effects on overall mortality. In general, more impressive results have been reported from trials conducted in Asia than elsewhere. PPI treatment for ulcer bleeding is not a substitute for appropriate endoscopic hemostatic treatment.

Effect of frequent dosing of an oral proton pump inhibitor on intragastric pH

BACKGROUND

Treatment with a continuous i.v. proton pump inhibitor is presumed to promote clot formation and stability by sustaining intragastric pH > or = 6.

AIM

We postulated that very frequent oral dosing of proton pump inhibitors should simulate i.v. infusion and achieve similar pH control.

METHODS

Twenty healthy volunteers were stratified by Helicobacter pylori status (10 positive; 10 negative) and had determination of CYP2C19 status. After an overnight fast, an intragastric pH probe was placed. Subjects received 120 mg of lansoprazole at 8 am and 30 mg every 3 h until 8 pm. Intragastric pH was measured over 24 h, and lansoprazole plasma concentrations were determined at five time points.

RESULTS

Intragastric pH was > or = 6 for 41% (95% CI: 30-53%) of the 15-h period from 8 am-11 pm and 46% (95% CI: 35-56%) of the 24-h period (8-8 am). The mean proportion of patients with pH > or = 6 was not significantly different in H. pylori-positive vs. negative patients. Only 25% of subjects sustained pH > or = 6 for at least 60% of the 15-h period, and 35% had a sustained pH > or = 6 for at least 60% of the 24-h period.

CONCLUSIONS

A dose of 120 mg of oral lansoprazole followed by standard 30 mg doses of lansoprazole every 3 h did not reliably sustain pH at the desired level of 6.

Proton pump inhibitor treatment for acute peptic ulcer bleeding

BACKGROUND

Randomised controlled trials (RCTs) evaluating the clinical effect of proton pump inhibitors (PPIs) in peptic ulcer (PU) bleeding yield conflicting results.

OBJECTIVES

To evaluate the efficacy of PPIs in acute bleeding from PU using evidence from RCTs.

SEARCH STRATEGY

We searched CENTRAL, The Cochrane Library (Issue 4, 2004), MEDLINE (1966 to November 2004), EMBASE (1980 to November 2004), proceedings of major meetings to November 2004, and reference lists of articles. We contacted pharmaceutical companies and experts in the field.

SELECTION CRITERIA

RCTs of PPI treatment (oral or intravenous) compared with placebo or H(2)-receptor antagonist (H(2)RA) in acute bleeding from PU.

DATA COLLECTION AND ANALYSIS

Two reviewers extracted data independently, assessed study validity, summarised studies and undertook meta-analysis. The influence of study characteristics on the outcomes was examined by subgroup analyses and meta-regression.

MAIN RESULTS

Twenty-four RCTs comprising 4373 participants in total were included. Statistical heterogeneity was found among trials for rebleeding (P = 0.04), but not for all-cause mortality (P = 0.24) or surgery (P = 0.45). There was no significant difference in all-cause mortality rates between PPI and control treatment; pooled rates were 3.9% on PPI versus 3.8% on control (odds ratio (OR) 1.01; 95% CI 0.74 to 1.40). PPIs significantly reduced rebleeding compared to control; pooled rates were 10.6% with PPI versus 17.3% with control treatment (OR 0.49; 95% CI 0.37 to 0.65). PPI treatment significantly reduced surgery compared with control; pooled rates were 6.1% on PPI versus 9.3% on control (OR 0.61; 95% CI 0.48 to 0.78). There was no evidence to suggest that results on mortality and rebleeding were dependent on study quality, route of PPI administration, type of control treatment or application of initial endoscopic haemostatic treatment. PPIs significantly reduced surgery compared with placebo but not when compared with H(2)RA. There was no evidence to suggest that study quality, route of PPI administration or application of initial endoscopic haemostatic treatment influenced results on surgery. PPI treatment appeared more efficacious in studies conducted in Asia compared to studies conducted elsewhere. All-cause mortality was reduced only in Asian studies; reductions in rebleeding and surgery were quantitatively greater in Asian studies. Among patients with active bleeding or non-bleeding visible vessel, PPI treatment reduced mortality (OR 0.53; 95% CI 0.31 to 0.91), rebleeding and surgery.

AUTHORS' CONCLUSIONS

PPI treatment in PU bleeding reduces rebleeding and surgery compared with placebo or H(2)RA, but there is no evidence of an overall effect on all-cause mortality.

The effect of regular and high doses of omeprazole on the intragastric acidity in patients with bleeding peptic ulcer treated endoscopically: a clinical trial with continuous intragastric pH monitoring

OBJECTIVE

In peptic ulcer bleeding (PUB), pH level >4 is considered necessary to prevent dissolving of a formed fibrin clot. The effect of regular or high doses of omeprazole on the intragastric pH in patients with acute PUB was studied.

METHODS

In our earlier study, after endoscopic therapy, PUB patients were randomized to receive a regular dose of intravenous omeprazole (20 mg; i.e. 60 mg/3 days) or a high dose of omeprazole (80 mg bolus + 8 mg/h; i.e. 652 mg/3 days). Of these 142 analysed and reported patients, 13 PUB patients also had intragastric pH monitoring for these 3 days; seven of these patients had a regular dose and six received a high dose of omeprazole.

RESULTS

The mean 24-h intragastric pH (regular versus high dose) on day 1 was 4.9 +/- 1.6 versus 6.3 +/- 0.5 (P = 0.035), on day 2 was 4.9 +/- 1.8 versus 6.7 +/- 0.3 (P = 0.001), and on day 3 was 5.7 +/- 1.1 versus 6.7 +/- 0.5 (P = NS). The medians of the intragastric pH were 6 versus 6.5 (P = 0.082) on day 1, 5.8 versus 6.8 (P = 0.001) on day 2, and 6.2 versus 6.8 (P = 0.17) on day 3. The proportion of time when pH <4 on day 1 was 29.2 +/- 34.1 versus 5.4 +/- 5.7% (P = NS).

CONCLUSIONS

A regular dose of omeprazole raises the mean and median 24-h intragastric pH >4 in patients with PUB. This reduction in the acidity together with endoscopic therapy is probably sufficient to maintain haemostasis. A high dose of omeprazole keeps the pH almost constantly >6.

Differences among desensitization of histamine H2 receptor induced by three H2 receptor antagonists on rat gastric parietal cells

AIM: To investigate the differences of the desensitization of the histamine H₂ receptor induced by three H₂ receptor antagonists on the gastric parietal cells in rats.

METHODS: The gastric parietal cells were isolated by pronase digestion and then divided into three groups: cimetidine, ranitidine and famotidine treatment group. The activity of the H⁺-K⁺-ATPase was detected by H⁺-K⁺-ATPase kit after the cells were treated with different concentrations of the antagonists for different times.

RESULTS: Significant changes of the H⁺-K⁺-ATPase activity were observed after the cells were treated with different concentrations of the antagonists at different times. The activities of H⁺-K⁺-ATPase were significantly higher in famotidine group at 1, 2, and 4 h (589.34±2.7, 812.82±8.35, 637.15±4.59) than those in ranitidine (169.38±93.64, 343.46±44.88, 234.07±4.72) and cimetidine (118.42±5.91, 110.62±1.28, 102.43±3.44) group (P <0.01). The activity in ranitidine group was markedly higner than that in cimetidine group at 2 and 4 h. Famotidine increased the activities of H⁺-K⁺-ATPase significantly at the concentrations of 10 and 100 mg/L(178.21±20.38, 225.65±16.41) as compared with ranitidine and cimetidine did (70.88±21.44, 128.03±8.22; 123.62±4.32, 125.40±7.45)(P <0.01). At the concentration of 1000 mg/L, both famotidine and ranitidine increased the activity of H⁺-K⁺-ATPase obviously as compared with cimetidine did (233.44±6.24, 131.58±11.50 vs 109.88±0.69, P <0.01, P <0.05).

CONCLUSION: Three H₂ receptor antagonists can induce different desensitization of the H₂ receptor, among which famotidine induces the strongest and cimetidine does the weakest.