Acute Kidney Injury Among Adults in the Pacific Islands: Incidence, Aetiology, Management and Outcome Measures From the Tertiary Referral Hospital of Samoa.

2. METHODS 2.1. Ethical approval Ethical approval for the present study was obtained from the Fiji National University College Health Research Ethics Committee (CHREC) and the Government of Samoa Ministry of Health - Health Research Committee (MoH-HRC). Gatekeeper approval was also obtained from the Deputy Director General of the TTM Hospital.

2.2. Study Design and Data Collection This was a single-centre prospective observational study. Participants were recruited from the hospital patient information system. The inclusion criteria for participation were (1) adults (>18 years) admitted to general wards of Tupua Tamasese Meaole (TTM) Hospital with a diagnosis of AKI between the 1st December 2019 and the 31st of May 2020, and (2) serum creatinine level of >200 micromol/L, and (3) compliance with the current Kidney Disease Improving Global Outcomes (KDIGO) criteria for AKI diagnosis. Patients with underlying chronic kidney disease who experienced an episode of AKI during the study period were also included in the present study. Exclusion criteria were (1) patients on chronic haemodialysis, (2) patients with underlying chronic kidney disease with no evidence of AKI, and (3) patients for whom it was not possible to ascertain a diagnosis (i.e., patients with one elevated serum creatinine result and no subsequent follow-up haematology).

The hospital Laboratory Database was accessed to identify all patients admitted to TTM Hospital during the study period with a serum creatinine level greater than 200 micromol/L. This is higher than the reference intervals for normal creatinine levels reported in the literature (60-110 micromol/L for adults males, 45-90 micromol/L for adult females) [10]. This criteria was chosen to align with the criteria used by the Fijian teaching hospital that is affiliated with the Fiji National University: the 200mcmol/L criteria reflects their AKI triage management guidelines based on the low-resourced context. The present study therefore adopted the same criteria to evaluate the similarly low-resourced context of Samoa. A total of 1185 patients were identified, and a request for their complete medical records was made to the Medical Record Department. Each record was reviewed for its suitability, and a total of 1071 records did not meet inclusion criteria. The sample size for the present study was therefore 114 patients.

The data collection form is an adaptation of the form used by the International Society for Nephrology for the Global Snapshot Project [11]. For each participant, the following information was collected:

2.2.1. Demographic and Baseline characteristics