Proton Pump Inhibitors vs. Histamine-2 REceptor Blockers for Ulcer Prophylaxis Therapy in the Intensive Care Unit

Patients who require treatment in the Intensive Care Unit (ICU) can develop stomach ulcers or duodenal (small intestine) ulcers. This occurs most commonly when life support (a breathing machine) is required or when the patient develops a bleeding tendency as a result of their illness. These kinds of ulcers are known as ‘stress ulcers’ and may cause life-threatening bleeding. Patients who require life support in the ICU are typically given one of two types of medicine to try and prevent the development of stress ulcers. The two types of medicines are called ‘proton pump inhibitors’ (PPIs) and ‘histamine-2 receptor blockers’ (H2RBs). While the prevention of stress ulcers is very important, the medicines used to prevent ulcers may have important side effects including an increased risk of developing certain kinds of infections. The risk of side effects may depend on the medication used. This study will establish which of the two types of medicines that are commonly used for stress ulcer prophylaxis in ICU patients who require life support leads to the lowest risk of upper gastrointestinal bleeding, prolonged mechanical ventilation, and Clostridium difficile infection. The study will use a design known as a ‘cluster crossover registry design’. In this type of study, data are collected primarily from existing data sources rather than the medical records of individual patients. There will be two study treatment periods. During the first treatment period, half of the participating ICUs will be randomly (like the toss of a coin) instructed to use PPIs for stress ulcer prophylaxis in patients who require life-support while the other half will use H2RBs. During the second treatment period each ICU will swap to using the opposite treatment. This means that, in situations where PPIs and H2RBs are regarded as being equivalent by the treating clinician, the treatment administered to the patients will be determined based on the treatment assigned to the patient’s ICU. However, if there is a specific indication for either PPI treatment or H2RB treatment (for example, an allergy), the treatment indicated for the particular patient concerned will be administered irrespective of the treatment assigned to the ICU.