RENAL FUNCTION IN PATIENTS UNDERGOING SURGERY

Abstract

<p>Reduced kidney function around the time of surgery is an important risk factor for postoperative mortality. Despite this there is limited information on how reduced kidney function prior to surgery alters prognosis, what causes sudden decrements in kidney function after surgery (known as acute kidney injury), or how they might be avoided. The studies in this thesis inform these knowledge gaps. Chapter 2 describes the results of a post hoc analysis of the interaction between preoperative estimated glomerular filtration rate, a marker of kidney function, and postoperative cardiac troponin T, a marker of heart damage, for predicting 30-day mortality in a prospective cohort study of patients undergoing noncardiac surgery. Chapter 3 uses administrative and clinical data from a single centre to inform the risk of acute kidney injury after noncardiac surgery by concentrations of preoperative hemoglobin and change in postoperative hemoglobin. Chapter 4 uses the same data to determine a definition of intraoperative hypotension that is prognostic of acute kidney injury, myocardial injury and death. Chapter 5 describes a randomized controlled trial that compares a novel therapeutic procedure called remote ischemic preconditioning to a sham procedure in patients undergoing cardiac surgery.</p>