Therefore, we aimed to evaluate the association selleck of factors at RRT initiation and especially cumulative fluid accumulation with 90-day mortality in critically ill adults.Materials and methodsPatientsWe performed a prospective, observational cohort study, the FINNAKI study, from 1 September 2011 to 1 February 2012, in 17 Finnish ICUs. The referral areas of these ICUs cover 85% of the Finnish adult population. The Ethics Committee of the Department of Surgery, Hospital District of Helsinki and Uusimaa approved the study protocol and the use of deferred consent with a signed, informed consent from the patient or a proxy obtained as soon as possible. The Finnish National Institute of Health approved the collection of data from medical records of deceased patients if an informed consent could not be obtained.

We included all adult patients with either emergency ICU admission or elective post-operative ICU admission with an expected ICU stay of more than 24 hours. We excluded patients 1) with end-stage renal disease (ESRD) on chronic dialysis 2) who had already participated in the FINNAKI study and had received RRT during that previous ICU admission 3) not permanently living in Finland or having insufficient language skills for giving an informed consent, and 4) on intermediate care (Figure (Figure1).1). Of patients receiving RRT, we excluded those who received RRT only for intoxication or plasmapheresis for non-renal indications. For analyses regarding fluid accumulation, we excluded patients with incomplete data on fluid balance.

The decision to initiate RRT and the choice of RRT modality were based on the judgment of the treating clinician.Figure 1Study flow chart with 90-day mortality rates. *ICU, intensive care unit; RRT, renal replacement therapy.Data collectionWe collected physiological data, laboratory values, Sequential Organ Failure Assessment (SOFA) [20] and Simplified Acute Physiology Score (SAPS) II [21] scores, Acute Physiology and Chronic Health Evaluation (APACHE) III diagnoses, and patients’ baseline weight with the help of the Finnish Intensive Care Consortium database using electronic patient records. We collected data on patients’ chronic illnesses, baseline creatinine (latest creatinine value a week to a year prior to ICU admission), and treatment prior to ICU admission.

The patients’ daily fluid balance was calculated in the electronic patient records by summing GSK-3 the amount of fluids given (maintenance and resuscitation fluids, blood products, drug infusions, and enteral and parenteral nutrition), from which losses (urine output, bleeding, output from drains, rectal and nasogastric tube, and surrogate for evaporation (1000 mL for normothermic patients, and an addition per each Celsius degree of fever per hour)) were subtracted.