Critically evaluate the use of selective decontamination of the digestive tract (SDD) in the ICU.
SDD is a prophylactic strategy to prevent or minimise the incidence of nosocomial infection from endogenous organisms and to prevent or minimise cross-infection by the application of nonabsorbable oral and enteric antibiotics and parenteral antibiotics.
Classically SDD has four components:
Nosocomial infections cause significant morbidity and mortality in the ICU. These infections arise from a limited number of potentially pathogenic micro-organisms (PPM) carried by healthy individuals (e.g. Staph aureus, E coli and C albicans) and opportunistic, aerobic Gram-negative bacilli (e.g. Klebsiella, Pseudomonas Acinetobacter) that colonise individuals when critically ill. The goal of SDD is to prevent or eradicate, if already present, at the start of ICU admission, the carriage of PPMs from the oropharynx and GI tract, leaving the indigenous flora, which protect against overgrowth with resistant bacteria, largely undisturbed.
Summary statement and Personal approach Any reasonable statement of candidate’s own approach, for example
This question is identical to Question 14 from the second paper of 2013. The answer has been reproduced below without any alterations. The college had also made minimal effort to change the answer since 2014, except where they deleted the middle words from the phrase "Patient groups studied include general ICU, burns, gastrointestinal surgery and transplant patients", leaving behind only "Patients patients" in an amusing proofreader fail.
The beneficial effects are expected to manifest in the following ways:
Critique of the evidence
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