Reducing the Frequency of Surveillance Blood Work in Patients Treated With Maintenance Hemodialysis: A Local Quality Improvement Initiative

TL;DR

This study found that reducing blood tests for dialysis patients from every 6 to 8 weeks did not harm outcomes and saved costs.

Contribution

The study provides local evidence supporting the safety of less frequent blood work in hemodialysis patients.

Findings

Reducing blood work frequency to every 8 weeks did not increase hospitalizations or deaths.

There was a slight increase in hyperkalemia cases and fewer phosphate values in target range.

The change saved $32,962 in costs related to anemia and mineral bone disease testing.

Abstract

There is little evidence on the ideal frequency of routine blood work in maintenance dialysis patients to manage complications, including anemia, mineral bone disease (MBD), and hyperkalemia. Recent quality improvement studies from Ontario showed no negative impacts when decreasing the frequency from monthly to every 6 weeks in conventional in-center hemodialysis (ICHD) patients. In December 2020, Alberta Kidney Care–South (AKC-S) reduced the frequency of routine blood work from every 6 weeks to every 8 weeks for ICHD patients.

We aimed to assess the impact of reducing blood work frequency on patient outcomes.

We compared prevalent AKC-S ICHD patients in 2 cohorts: (1) retrospective control (October 31, 2019-October 31, 2020) and (2) prospective intervention (December 1, 2020-December 1, 2021). Primary outcomes were true frequency of routine blood work, odds of patients being within target for anemia and MBD, and proportion of lab values of hyperkalemia. Furthermore, we compared hospitalizations and mortality.

A total of 972 patients in Calgary’s ICHD program were included, 787 in each period (with 602 patients overlapping both cohorts). The frequency of routine blood work decreased from every 39.5 days in the control period to every 54.2 days in the intervention period (P < .01). There was a reduction in the odds of phosphate values in targets (P = .02), and an increase in the odds of labs with hyperkalemia (>6.0 mmol/L) during the intervention period (P = .01). There was no significant change in the odds of being within the accepted targets during the intervention period compared with the control period for hemoglobin, Tsat, calcium, or parathyroid hormone (PTH). Fewer patients were hospitalized during the intervention period and the risk of death decreased as well, although additional factors such as the COVID-19 pandemic may have affected this. A cost-savings of $32 962 occurred from the reduced anemia and MBD blood work during the intervention period.

When ICHD units in Calgary reduced routine blood work frequency from every 6 weeks to 8 weeks, there were no negative impacts on hospitalizations or deaths. A slightly lower proportion of phosphate values were within target, and a 0.7% increase in potassium values greater than 6 mmol/L was demonstrated. Our study suggests that blood work frequency in ICHD dialysis patients may be further reduced to every 8 weeks safely. Ultimately, additional pragmatic trials are needed to identify the optimal frequency of routine blood work.

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