Guy A Richards
Charlotte Maxeke Johannesburg Academic Hospital, South Africa
Title: Antibiotic Stewardship: Optimising the administration of antibiotics in critically ill patients
Biography
Biography: Guy A Richards
Abstract
Optimal outcome and a reduction in the potential for resistance require that appropriate pharmacokinetic (PK) targets are achieved. Consequently, we need to target drug concentrations that are significantly higher than those conventionally presumed to be adequate. Drug exposure varies according to the molecular weight, degree of ionisation, protein binding and lipid solubility of each agent. In critically ill patients, hypoalbuminaemia increases the free fraction of hydrophilic drugs, which in turn increases the volume of distribution and clearance (CL), both of which result in reduced drug levels. Similarly, augmented renal clearance (ARC), defined as a creatinine clearance (CLcr) of >130 mL/min/1.73 m2, which occurs frequently in critically ill patients, particularly younger patients with normal or near-normal creatinine levels, may also significantly reduce drug exposure. Studies have demonstrated a greater mortality and lower cure with ARC, particularly with the additive effects of obesity, hypoalbuminaemia and increasing resistance, if conventional dosages are used. These concepts apply to antibiotics targeting Gram-negative and -positive organisms. Knowledge of PK and the resistance profiles of organisms in each environment is necessary to prescribe appropriately. This article discusses these issues and the doses that should be used.
Biography: Prof Richards specialised in internal medicine in 1985 and subsequently as a pulmonologist and intensivist. He was awarded his PhD in medicine in 1992 and has authored 12 book chapters, 126 peer reviewed scientific papers and has 1196 citations. His Score on ResearchGate is 39.58. He has reviewed for the International Journal of Antimicrobial Agents, European Journal of Clinical microbiology and Infectious Diseases, BMC infectious diseases, antimicrobial agents and chemotherapy, Thorax , the International journal of Tuberculosis, Critical Care and others.