The SuDDICU Study of Antibiotic Prophylaxis in Critical Illness

Selective Decontamination of the Digestive Tract (SDD) is a treatment designed to reduce the risk of infection and improve survival for critically ill patients. SDD is the application of antibiotics and antifungal drugs to the throat and their instillation into the stomach, combined with a short course of intravenous antibiotics. Although many trials suggest that SDD works, the research results have not been convincing enough to lead to the widespread uptake of SDD around the world. Additionally clinicians are concerned that SDD will increase antibiotic resistance amongst endemic bacteria. As a result, SDD is not currently widely practiced. This trial aims to resolve this uncertainty. We will be conducting the definitive randomised study examining the effect of implementing SDD. For 24 months, ICUs in Australia will be randomly assigned to either deliver SDD in the first 12-month period and be a control ICU in the second 12-month period, or to be a control ICU first and deliver SDD in the second period. 8000 critically ill mechanically ventilated patients will be enrolled. Mortality rates will be compared between the SDD and control groups antibiotic resistance rates will be evaluated in samples from all patients prior to, during and after the trial to determine the effect of SDD on the microbial ecology. The SuDDICU trial will provide definitive answer to a fundamental question in intensive care medicine - does SDD reduce critically ill patients’ risk of dying without increasing antibiotic resistance rates? If SDD is found to be effective without increasing antibiotic resistance, the study will have a global impact, leading to improved survival and reduced infection rates in critically ill patients. The results of this study will change practice and be of immense value to clinicians, policy makers and regulators.