Original Investigation 

November 3, 2022

Association Between Preoperative Hemodialysis Timing and Postoperative Mortality in Patients With End-stage Kidney Disease

Vikram Fielding-Singh, Matthew W. Vanneman, Tristan Grogan, et al

JAMA. 2022;328(18):1837-1848. doi:10.1001/jama.2022.19626

Key Points

Question  Is there an association between the timing of preoperative hemodialysis relative to surgery and postoperative mortality in patients with end-stage kidney disease who are treated with hemodialysis?

Findings  In this retrospective cohort study of 1 147 846 surgical procedures among 346 828 Medicare beneficiaries with end-stage kidney disease treated with hemodialysis, longer intervals between hemodialysis and subsequent surgical procedure were significantly associated with increased risk of postoperative 90-day mortality in a dose-dependent manner (2 days vs 1 day: adjusted hazard ratio [HR], 1.14; 3 days vs 1 day: adjusted HR, 1.25; and 3 days vs 2 days: adjusted HR, 1.09), although the findings were attenuated after accounting for receipt of hemodialysis on the same day as surgery.

Meaning  Among Medicare beneficiaries with end-stage kidney disease, longer intervals between hemodialysis and surgery were associated with higher risk of postoperative mortality, mainly among those who did not receive hemodialysis on the day of surgery, although the magnitude of the absolute risk differences was small and the findings are susceptible to residual confounding.

Abstract

Importance  For patients with end-stage kidney disease treated with hemodialysis, the optimal timing of hemodialysis prior to elective surgical procedures is unknown.

Objective  To assess whether a longer interval between hemodialysis and subsequent surgery is associated with higher postoperative mortality in patients with end-stage kidney disease treated with hemodialysis.

Design, Setting, and Participants  Retrospective cohort study of 1 147 846 procedures among 346 828 Medicare beneficiaries with end-stage kidney disease treated with hemodialysis who underwent surgical procedures between January 1, 2011, and September 30, 2018. Follow-up ended on December 31, 2018.

Exposures  One-, two-, or three-day intervals between the most recent hemodialysis treatment and the surgical procedure. Hemodialysis on the day of the surgical procedure vs no hemodialysis on the day of the surgical procedure.

Main Outcomes and Measures  The primary outcome was 90-day postoperative mortality. The relationship between the dialysis-to-procedure interval and the primary outcome was modeled using a Cox proportional hazards model.

Results  Of the 1 147 846 surgical procedures among 346 828 patients (median age, 65 years [IQR, 56-73 years]; 495 126 procedures [43.1%] in female patients), 750 163 (65.4%) were performed when the last hemodialysis session occurred 1 day prior to surgery, 285 939 (24.9%) when the last hemodialysis session occurred 2 days prior to surgery, and 111 744 (9.7%) when the last hemodialysis session occurred 3 days prior to surgery. Hemodialysis was also performed on the day of surgery for 193 277 procedures (16.8%). Ninety-day postoperative mortality occurred after 34 944 procedures (3.0%). Longer intervals between the last hemodialysis session and surgery were significantly associated with higher risk of 90-day mortality in a dose-dependent manner (2 days vs 1 day: absolute risk, 4.7% vs 4.2%, absolute risk difference, 0.6% [95% CI, 0.4% to 0.8%], adjusted hazard ratio [HR], 1.14 [95% CI, 1.10 to 1.18]; 3 days vs 1 day: absolute risk, 5.2% vs 4.2%, absolute risk difference, 1.0% [95% CI, 0.8% to 1.2%], adjusted HR, 1.25 [95% CI, 1.19 to 1.31]; and 3 days vs 2 days: absolute risk, 5.2% vs 4.7%, absolute risk difference, 0.4% [95% CI, 0.2% to 0.6%], adjusted HR, 1.09 [95% CI, 1.04 to 1.13]). Undergoing hemodialysis on the same day as surgery was associated with a significantly lower hazard of mortality vs no same-day hemodialysis (absolute risk, 4.0% for same-day hemodialysis vs 4.5% for no same-day hemodialysis; absolute risk difference, −0.5% [95% CI, −0.7% to −0.3%]; adjusted HR, 0.88 [95% CI, 0.84-0.91]). In the analyses that evaluated the interaction between the hemodialysis-to-procedure interval and same-day hemodialysis, undergoing hemodialysis on the day of the procedure significantly attenuated the risk associated with a longer hemodialysis-to-procedure interval (P<.001 for interaction).

Conclusions and Relevance  Among Medicare beneficiaries with end-stage kidney disease, longer intervals between hemodialysis and surgery were significantly associated with higher risk of postoperative mortality, mainly among those who did not receive hemodialysis on the day of surgery. However, the magnitude of the absolute risk differences was small, and the findings are susceptible to residual confounding.