Incidence and Outcomes of Acute Kidney Injury in Postoperative ICU Patients - a Retrospective Data Analysis

Acute kidney injury (AKI) is a common complication in critically ill patients. Based on the sensitive KDIGO criteria, the incidence of AKI on ICU varies between 30-60 %. These large variations of incidence of AKI are due to different baseline characteristics of studied patients, the length of observation period, use of creatinine criteria only or use of creatinine and urine output criteria. Furthermore, back estimation of baseline creatinine instead of measured creatinine in patients with missing laboratory values may lead to overestimation of AKI severity and outcomes. Major surgery, trauma, infection, sepsis or a complication of severe illness can lead to an abrupt decrease in glomerular filtration in critically ill patients. Such episode of AKI is associated with short term adverse effects such as fluid overload, electrolyte imbalance, acid-base derangements, immune dysfunction, coagulation abnormalities and alterations in mental status. Additionally, AKI in critically ill patients leads to prolonged ICU length of stay, increase in morbidity and mortality as well as higher costs. Multiple large studies found, after correction for potential confounders, that AKI was independently associated with worse outcomes. Moderate and severe AKI stages were associated with 2.9 - 6.9 fold increased in-hospital mortality (3). Increasing AKI severity in ICU patients was not only associated with increased mortality, AKI patients had also worse renal function at the time of hospital discharge. The individual condition leading to AKI in combination with increased susceptibility to AKI may significantly influence outcome. Indeed, current data from many studies show that mortality from AKI differs in various clinical settings.

However, there are not enough data on different types of surgery and their effect on AKI yet. The aim of our epidemiological study is to investigate the occurrence and outcomes of AKI in different types of surgery in postoperative ICU patients at the Vienna General Hospital.

Study Overview

• Status: Completed
• Conditions: Acute Kidney Injury; ICU; Postoperative Patients

• Study Type: Observational
• Enrollment (Actual): 5000

Contacts and Locations

Study Locations

• Austria
  • Vienna, Austria
    • Medical University of Vienna

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

retrospective data analysis of postoperative ICU patients admitted to anaesthesiological and surgical ICUs of the General Hospital Vienna, Austria between January 1, 2016 and December 31, 2018.

Description

Inclusion Criteria:

• age > 18 years
• postoperative ICU admission
• preoperative serum creatinine within 2 weeks prior surgery

Exclusion Criteria:

• age < 18 years
• no surgery prior to ICU admission
• renal transplantation prior ICU admission
• chronic renal replacement therapy
• peritoneal dialysis
• missing preoperative serum creatinine within 2 weeks prior surgery

Study Plan

How is the study designed?

Design Details

• Observational Models: Cohort
• Time Perspectives: Retrospective

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
28 day mortality	primary outcome is the 28-day mortality in different stages of AKI according to KDIGO criteria in patients admitted in the ICU after surgery.	28 days

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
ICU length of stay	secondary outcomes are length of stay in the ICU, receipt and duration of mechanical ventilation, receipt and duration of renal replacement therapy and 1- year all-cause mortality	1 year
receipt and duration of mechanical ventilation		1 year
receipt and duration of renal replacement therapy		1 year
1-year all cause mortality		1 year

Collaborators and Investigators

• Sponsor: Medical University of Vienna

Study record dates

Study Major Dates

• Study Start (Actual): June 13, 2019
• Primary Completion (Actual): June 30, 2021
• Study Completion (Actual): July 30, 2021

Study Registration Dates

• First Submitted: July 30, 2019
• First Submitted That Met QC Criteria: July 30, 2019
• First Posted (Actual): August 1, 2019

Study Record Updates

• Last Update Posted (Actual): November 30, 2021
• Last Update Submitted That Met QC Criteria: November 29, 2021
• Last Verified: November 1, 2021

More Information

Terms related to this study

• Keywords: ICU; postoperative; AKI; KDIGO
• Additional Relevant MeSH Terms: Kidney Diseases; Urologic Diseases; Renal Insufficiency; Wounds and Injuries; Acute Kidney Injury
• Other Study ID Numbers: EK Nr. 1419/2019

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: No

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No