Interventions to prevent hemodynamic instability during renal replacement therapy for acute kidney injury: a systematic review protocol

Background: Hemodynamic instability during renal replacement therapy (HIRRT) in the form of intradialytic hypotension (IDH) is a frequent complication of hemodialysis in end-stage kidney disease (ESKD), and most studies have focused on this chronic population. However, HIRRT is also an important concern for critically ill ICU patients with acute kidney injury (AKI), complicating an estimated 30% of dialysis treatments in this population. HIRRT can exacerbate organ hypoperfusion in the setting of critical illness and may negatively impact renal recovery in the AKI population. This is a protocol for a systematic review to synthesize the evidence surrounding dialysis-related interventions used to minimize HIRRT in critically ill patients with RRT-requiring AKI. This protocol has been registered with the International Prospective Register of Systematic Reviews (PROSPERO) database. Methods/design: We will search MEDLINE, EMBASE, and CENTRAL databases in collaboration with a health information specialist using a comprehensive search strategy. We will also supplement our search with a scan of the "gray literature"to identify relevant ongoing trials or conference abstracts. Observational studies and clinical trials will be included in our analysis. Our outcomes will include the incidence of HIRRT, dialysis-related complications, in-hospital mortality, and renal recovery. Prior to our search, we performed an initial search of these databases and PROSPERO, which yielded no prior or ongoing systematic reviews on this topic. Two reviewers will independently screen the list of identified abstracts using pre-defined inclusion and exclusion criteria. Two reviewers will then independently extract data from selected studies and undertake an assessment of their quality using validated tools. Discussion: HIRRT is a common complication of renal replacement therapy not only in ESKD but also in the critically ill AKI population. It can result in early discontinuation of dialysis, further organ injury from hypoperfusion, and possibly negatively impact renal recovery. This systematic review will synthesize the existing evidence on the interventions employed to predict or prevent episodes HIRRT in critically ill patients with RRT-requiring AKI. This systematic review will allow for an understanding the current evidence for interventions to limit HIRRT in AKI and, in doing so, may also highlight areas in need of further research.