Sauder School of Business, University of British Columbia, Vancouver, Canada.
Division of Nephrology, Department of Medicine, University of British Columbia, Vancouver, Canada.
Am J Kidney Dis. 2014 Jan;63(1):95-103. doi: 10.1053/j.ajkd.2013.06.021. Epub 2013 Aug 24.
The optimal time for arteriovenous fistula (AVF) referral is uncertain. Improving the timeliness of referral may reduce central venous catheter (CVC) use.
Monte Carlo simulation model.
SETTING & POPULATION: Patients with chronic kidney disease (CKD) followed up in a multidisciplinary clinic, overall and stratified by age.
MODEL, PERSPECTIVE, & TIMEFRAME: Decision analysis, patient, patient's lifetime.
AVF referral, using 1 of 2 strategies: refer when hemodialysis is anticipated to begin within a certain time frame or refer when estimated glomerular filtration rate (eGFR) drops below a certain threshold.
A range of values for each strategy are compared to each other with respect to incident vascular access type (AVF or CVC), percentage of patients with an unnecessary AVF creation, and life expectancy after dialysis therapy initiation.
A 15-month referral time frame gave 34% with incident CVCs, 14% with unnecessary AVFs, and a life expectancy of 1,751 days. Time frames of 12-18 months performed similarly. Referral at eGFR of 20 mL/min/1.73 m(2) gave 38% with incident CVCs, 20% with unnecessary AVFs, and life expectancy of 1,742 days. Using an eGFR threshold of 15 mL/min/1.73 m(2), 10% had an unnecessary AVF. Policy performance was affected by CKD progression rate and age. For fast progressors (ΔeGFR = -7mL/min/1.73 m(2) per year), referral at eGFR of 25 mL/min/1.73 m(2) achieved a similar incident CVC percentage (~40%) as referral at 15 mL/min/1.73 m(2) in slower progressors (ΔeGFR = -2.78 mL/min/1.73 m(2) per year). For patients aged 70-80 and 80-90 years, time frames of 15-18 months yielded 16%-22% with unnecessary AVFs (vs 9%-11% in 50- to 60-year-olds); an eGFR threshold strategy of 20 mL/min/1.73 m(2) yielded 24% unnecessary AVFs in 80- to 90-year-olds versus 16% in 50- to 60-year-olds.
Our model does not consider patients with nonlinear CKD progression or acute kidney injury. We did not include arteriovenous grafts or consider cost or quality of life.
In general, AVF referral within about 12 months of the estimated time to dialysis performed best among time frame strategies, and referral at eGFR < 15-20 mL/min/1.73 m(2) performed best among threshold strategies. The timing of referral should also be guided by the individual rate of CKD progression. Elderly patients with CKD could be referred later to reduce the risk of creating an AVF that is never used.
动静脉瘘（AVF）转介的最佳时间不确定。提高转介的及时性可能会减少中心静脉导管（CVC）的使用。
蒙特卡罗模拟模型。
在多学科诊所接受慢性肾脏病（CKD）治疗的患者，总体上和按年龄分层。
模型、观点和时间范围：决策分析，患者，患者的一生。
AVF 转介，使用以下两种策略之一：在预计在特定时间范围内开始血液透析时转介，或在估算肾小球滤过率（eGFR）降至特定阈值以下时转介。
与其他策略相比，每种策略的一系列值在血管通路类型（AVF 或 CVC）的发生率、不必要的 AVF 发生率以及透析治疗开始后的预期寿命方面进行了比较。
15 个月的转介时间框架导致 34%的患者出现 CVC，14%的患者出现不必要的 AVF，预期寿命为 1751 天。12-18 个月的时间框架表现类似。eGFR 为 20 mL/min/1.73 m(2)时转介导致 38%的患者出现 CVC，20%的患者出现不必要的 AVF，预期寿命为 1742 天。使用 eGFR 阈值为 15 mL/min/1.73 m(2)时，10%的患者出现不必要的 AVF。政策表现受 CKD 进展速度和年龄的影响。对于快速进展者（ΔeGFR=-7mL/min/1.73 m(2)每年），eGFR 为 25 mL/min/1.73 m(2)时的转介与较慢进展者（ΔeGFR=-2.78 mL/min/1.73 m(2)每年）的 eGFR 为 15 mL/min/1.73 m(2)时的转介具有相似的 CVC 发生率（~40%）。对于 70-80 岁和 80-90 岁的患者，15-18 个月的时间框架导致 16%-22%的患者出现不必要的 AVF（50-60 岁的患者为 9%-11%）；eGFR 阈值策略为 20 mL/min/1.73 m(2)导致 80-90 岁的患者出现 24%的不必要 AVF，而 50-60 岁的患者为 16%。
我们的模型不考虑 CKD 进展呈非线性或急性肾损伤的患者。我们没有包括动静脉移植物，也没有考虑成本或生活质量。
一般来说，在时间框架策略中，估计透析时间后约 12 个月内进行 AVF 转介表现最佳，而在阈值策略中，eGFR<15-20 mL/min/1.73 m(2)时表现最佳。转介时间也应根据 CKD 进展的个体速度来指导。患有 CKD 的老年患者可以推迟转介，以减少创建从未使用过的 AVF 的风险。
