Long term outcomes in acute kidney injury patients

Published Date: 19th July 2016

Publication Authors: Tridente A

​

Introduction and Aims

Acute kidney injury (AKI) affects 40% of critically ill patients with UK data reporting 5% needing renal r​eplacement therapy (RRT). Hospital mortality is reported as being up to 60%. We sought to evaluate renal and long term patient survival outcomes in AKI patients receiving RRT on our ICU. 

 

Methods

Data was collected from our computerised information system on all AKI patients receiving RRT on our ICU, between Oct 2008 and Oct 2013. This included demographics, APACHE II and SOFA scores, modality & dose of RRT and ICU length of stay (LOS). Renal and patient survival at ICU discharge was collected, in addition to outcome data at 28 & 90 days and 12 months. Patient survival was followed up for a minimum of oner & maximum of six years. Data was examined using Cox proportional hazard  multivariate analysis, adjusted for age & sex, with Stata 10.1 

 

Results

620 patients with AKI received RRT on our ICU between Oct 2008 & Oct 2013. 61% were males. Median age was 65 years (IQR 54-74). Median APACHE II score was 23 (IQR 18-27). Median SOFA score was 11 (IQR 8-13). 55% were mechanically ventilated. 96.7% received CVVH as the principal RRT modality. 21% received a period of high volume hemofiltration (HVHF) (80ml/kg/hr), median LOS was 6 days (IQR 3-14). 331 (53.4%) patients recovered their renal function at ICU discharge, whilst 237 (38.2%), 220 (35.4%), 220 (35.4%) patients did not, at 28 & 90 days and 12 months respectively. 414 (66.7%) patients survived to ICU discharge, with 3​68 (59.3%), 341 (55%) & 308 (49.6%) patients being alive at 28 & 90 days and 12 months respectively. Overall patient survival at end of follow up was 43%. Adjusting for age & sex; APACHE II, SOFA score and use of HVHF were associated with worse patient survival at ICU discharge (HR 1.07, 95% CI:1.03-1.11, p<0.001, HR: 1.11, 95% CI:1.03-1.19, p=0.006 & HR: 2.27, 95% CI: 1.4-3.66, p=0.001, respectively). Adjusting for age & sex; APACHE II and use of HVHF were associated with worse renal recovery at ICU discharge (HR: 1.06, 95% CI: 1.03-1.09, p<0.001 & HR: 1.55, 95% CI: 1.03-2.3, p=0.032 respectively). SOFA score did not appear to significantly impact renal recovery (HR: 0.99, 95% CI: 0.94-1.04, p=0.81). 

 

Conclusions

Our Results suggest that, in patients with AKI presenting to ICU for RRT, long term patient survival is significantly impaired. Renal outcomes are poor with 35% being either dialysis-dependent or having severe chronic kidney disease (eGFR<15mls/min), at one year from ICU discharge. Our data does not suggest a benefit of using HVHF in AKI patients presen​ting to ICU for RRT.

 

Elsayad, I; Tridente, A et al. (2015). Long term outcomes in acute kidney injury patients receiving continuous renal replacement therapy on intensive care unit in a large teaching hospital​ . Nephrology Dialysis Transplantation. 30 (Suppl 3), iii452-iii453.

 

« Back