Association between acute kidney injury, delirium and outcomes in patients with critical illness: a protocol for a systematic review.

INTRODUCTION

Acute kidney injury (AKI) and delirium are common clinical complications of critical illness. Relatively few studies have evaluated the relationship between AKI and delirium. This systematic review will assess this association among critically ill patients.

METHODS AND ANALYSIS

We will conduct comprehensive searches of databases, including Ovid MEDLINE, Ovid Embase, CINAHL, Scopus, Web of Science Core Collection and the Cochrane Library, using keywords to capture the existing literature related to AKI and delirium. Searches will range from inception to January 2025. Two reviewers will independently screen, select and extract studies using the web-based tool, Covidence. Inclusion criteria will include clinical trials or observational cohorts reporting both AKI and delirium in patients admitted to intensive care units. Case reports, case series and preclinical or experimental studies will be excluded. The quality and risk of bias will be assessed using the Newcastle-Ottawa Scale for observational studies and the Cochrane Risk-of-Bias tool for randomised controlled trials. The primary outcome will be the proportion of critically ill patients with AKI who develop delirium. Secondary outcomes will include the proportion of patients with delirium stratified by AKI severity or receipt of renal replacement therapy as well as clinical factors associated with delirium, mortality and health service outcomes, including organ support use and lengths of stay.

ETHICS AND DISSEMINATION

Ethics approval is not required for this study, as all data included in this evaluation are already published, and our study will not directly involve human participants. Findings will be disseminated through academic conferences and published in a peer-reviewed journal.

PROSPERO REGISTRATION NUMBER

CRD420251001864.