Algorithm for optimal dialysis access timing.
BACKGROUND
Acute initiation of dialysis is associated with increased morbidity due to access and uremia complications. It is frequent despite early referral and regular out-patient control. We studied factors associated with end-stage renal disease (ESRD) progression in order to optimize the timing of dialysis access (DA).


METHODS
In a retrospective longitudinal study (Study 1), the biochemical and clinical course of 255 dialysis and 64 predialysis patients was registered to determine factors associated with dialysis-free survival (DFS). On the basis of these results an algorithm was developed to predict timely DA, defined as >6 weeks and <26 weeks before dialysis initiation, with too late placement weighted twice as harmful as too early. The algorithm was validated in a prospective study (Study 2) of 150 dialysis and 28 predialysis patients.


RESULTS
Acute dialysis was associated with increased 90-day hospitalization (17.9 vs. 9.0 days) and mortality (14% vs. 6%). P-creatinine and p-urea were poor indicators of DFS. At any level of p-creatinine, DFS was shorter with lower creatinine clearance and vice versa. Patients with systemic renal disease had a significantly shorter DFS than primary renal disease, due to faster GFR loss and earlier dialysis initiation. Short DFS was seen with hypoalbuminemia and cachexia; these patients were recommended early DA. The following algorithm was used to time DA (units: 1iM and ml/min/1.73 m2): P-Creatinine - 50 x GFR + (100 if Systemic Renal Disease) >200. Use of the algorithm was associated with earlier dialysis placement and a fall in acute dialysis requirements from 50% to 23%. The incidence of too early DA was unchanged (7% vs. 9%), and was due to algorithm non-application. The algorithm failed to predict imminent dialysis in 10% of cases, primarily due to acute exacerbation of stable uremia. Dialysis initiation was advanced by approximately one month.


CONCLUSIONS
A predialysis program based on early dialysis planning and GFR-based DA timing may reduce the requirement for acute dialysis initiation and patient morbidity and mortality, at the cost of slightly earlier dialysis initiation.
Heaf
J G
JG
Department of Nephrology, Copenhagen University Hospital, Herlev, Denmark. heaf@dadlnet.dk
D000328:Adult; D000368:Aged; D000465:Algorithms; D015331:Cohort Studies; D003404:Creatinine / Q000097:blood*; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007676:Kidney Failure, Chronic / Q000097:blood* / Q000628:therapy*; D008137:Longitudinal Studies; D008297:Male; D008485:Medical Audit; D008875:Middle Aged; D011785:Quality Assurance, Health Care; D006435:Renal Dialysis / Q000379:methods / Q000592:standards*; D012189:Retrospective Studies; D013997:Time Factors
D003404:Creatinine