什麼時候該開始準備洗腎廔管？不是等到要洗腎才處理
When Should You Start Planning a Dialysis Fistula?
中文版
「醫師說腎功能可能會繼續下降，我現在就要做廔管嗎？」開始準備血管通路，不等於立刻開始透析，也不代表每一位慢性腎臟病病人都需要做廔管。
真正的目的，是在血液透析可能成為未來選項時，預留足夠時間評估血管、選擇通路，並降低到了緊急洗腎時只能先放置中央靜脈導管的機會。
大家常說的「洗腎廔管」，正式名稱是動靜脈廔管（arteriovenous fistula, AV fistula）。醫師會將一條動脈和一條表淺靜脈連接，讓靜脈逐漸變粗、血流增加，之後才能承受規律血液透析的穿刺。
eGFR 的中文是「估算腎絲球過濾率」，常被簡單稱為腎功能數字。它是利用抽血中的肌酸酐，配合年齡、性別等資料，估算腎臟過濾血液與清除廢物的能力。可以把它想成腎臟的「過濾能力指標」：一般而言，數字越低，代表腎臟的過濾功能越差。eGFR 不是百分比，也不能只用一次檢查結果決定是否需要透析。
- eGFR（估算腎臟過濾功能）低於約 15–20 mL/min/1.73m²，且腎功能持續下降
- 預估兩年內需要腎臟替代治療的風險高於 40%
- 腎臟科評估血液透析很可能成為未來選項
- 血管條件可能較困難，需要提早保留與評估手臂血管
1.哪些人應該開始討論血管通路？
- KDIGO 2024 慢性腎臟病指引建議，成人若 eGFR 低於約 15–20 mL/min/1.73m²，或預估兩年內需要腎臟替代治療的風險高於 40%，可以開始規劃腎臟移植或透析通路。
- 臨床上還要看數次抽血的腎功能趨勢、蛋白尿、反覆急性腎損傷，以及水分、血鉀、酸鹼、血壓或營養狀況是否越來越難控制。不能只根據一次 eGFR 決定。
- 若腎臟科醫師評估未來較可能選擇血液透析，就可以開始了解廔管、人工血管與導管的差異，並安排血管評估。
2.哪些情況需要更早評估手臂血管？
- 糖尿病、周邊動脈疾病、手臂血管較細，或過去已有血管通路失敗。
- 曾放置中央靜脈導管、PICC 或心律調節器；這些病史可能影響中央靜脈與未來通路選擇。
- 在醫療團隊指示下，應避免在預計保留的手臂做不必要的抽血、點滴或 PICC，以免可用靜脈受損。先詢問腎臟科哪一側需要保留，不要自行指定。
3.為什麼不能等到要洗腎時才做？
- 動靜脈廔管建立後需要時間成熟，有些廔管也可能成熟不足，需要額外評估、血管擴張或手術調整。
- 提早規劃可以先用理學檢查與超音波了解手臂動脈、靜脈的大小、走向、深度與血流，並依預計透析時間安排合適的建立時點。
- 但也不是越早做越好。若腎功能長期穩定、可能先接受腎臟移植、選擇腹膜透析，或整體健康狀況使血液透析的好處有限，過早建立廔管可能成為不必要的手術。
4.廔管、人工血管與導管，哪一種比較適合？
- 自體動靜脈廔管適合有合適動脈與靜脈、而且有時間等待成熟的人；但不是每一條廔管都能順利成熟。
- 人工血管可能用於自體靜脈條件不足，或需要較快建立可用通路的情況；之後仍要持續追蹤狹窄與感染。
- 中央靜脈導管多用於必須緊急透析，或暫時沒有其他可用通路時；通常視為暫時性通路。
- KDOQI 指引強調個人化的 ESKD Life-Plan：透析方式、移植可能性、血管條件、預計使用時間、共病與個人選擇都要一起考慮。動靜脈廔管是合適病人的重要選項，但不是每個人的唯一答案。
5.第一次血管通路評估會做什麼？
- 了解慣用手、過去導管、心律調節器與手術病史，以及腎臟科規劃的腎臟替代治療方向。
- 檢查雙手脈搏、皮膚、靜脈與血液循環，再以超音波測量動脈與靜脈。
- 血管外科與腎臟科一起決定是否需要建立通路、適合的種類、位置與時間。準備廔管和開始透析，是兩個不同的決定。
💡 看到這些情況，可以先做什麼？
| 目前情況 | 可以先做的事 | 不代表什麼 |
|---|---|---|
| eGFR 約 15–20，或兩年腎衰竭風險升高 | 和腎臟科討論透析、移植與保守治療選項 | 不是立刻開始洗腎 |
| 血液透析很可能成為未來選擇 | 轉介血管外科，安排手臂血管超音波 | 不是每個人都一定做自體廔管 |
| 血管細，或曾放中央導管、PICC、心律調節器 | 提早說明病史並評估可用血管與中央靜脈 | 不是自行決定保留哪一側 |
| 出現難控制的水腫、高血鉀、酸中毒或尿毒症狀 | 儘快由腎臟科評估是否接近需要腎臟替代治療 | 不能只靠 eGFR 判斷 |
常見問題
腎功能第四期，就一定要做廔管嗎？
不一定。需要把腎功能下降速度、兩年腎衰竭風險、預計透析方式、血管條件、整體健康與個人意願一起評估。
做了廔管，就代表很快要開始洗腎嗎？
不是。建立通路是為可能的血液透析預作準備；真正開始透析的時機，仍由症狀、生活品質、腎功能、檢驗結果與病人意願共同決定。
第一次評估就會安排手術嗎？
不一定。第一次通常先確認腎臟科的治療方向、既往導管與手術史，再做手臂血管檢查與超音波。是否手術及時間點要個別討論。
⚠️ 溫馨提醒：開始規劃廔管，不等於立刻開始透析。是否需要血管通路、選擇哪一種以及何時建立，都要由腎臟科、血管外科與病人共同決定。
ENGLISH
“My kidney function may continue to decline. Does that mean I need a fistula now?” Planning a dialysis access does not mean that dialysis must start immediately, and not every person with advanced chronic kidney disease needs a fistula.
The purpose is to allow enough time to assess the arm vessels, choose an appropriate access and reduce the chance of needing an urgent central venous catheter if haemodialysis becomes necessary.
An arteriovenous fistula (AV fistula) is created by connecting an artery to a superficial vein. The increased blood flow allows the vein to enlarge and strengthen so it can later support repeated haemodialysis cannulation.
eGFR stands for estimated glomerular filtration rate. It is calculated from a blood creatinine result together with factors such as age and sex, and estimates how well the kidneys filter blood and remove waste. Think of it as a kidney filtration indicator: in general, a lower number means poorer filtering function. eGFR is not a percentage, and a single result does not decide whether dialysis is needed.
- eGFR (an estimate of kidney filtering function) below approximately 15–20 mL/min/1.73m² with progressive decline
- An estimated 2-year risk of kidney replacement therapy above 40%
- Haemodialysis is likely to become the preferred future option
- Vascular anatomy may be difficult and needs earlier preservation and assessment
1.Who should start discussing dialysis access planning?
- The KDIGO 2024 CKD guideline advises considering planning for kidney transplantation and/or dialysis access in adults when eGFR is below approximately 15–20 mL/min/1.73m², or when the estimated 2-year risk of kidney replacement therapy is above 40%.
- The decision also considers the trend across repeated tests, proteinuria, recurrent acute kidney injury, and whether fluid status, potassium, acid–base balance, blood pressure or nutrition are becoming difficult to control. A single eGFR result is not enough.
- If the nephrology team believes haemodialysis is likely to become the preferred future option, it is reasonable to learn about fistulas, grafts and catheters and arrange vascular assessment.
2.Who may need earlier vessel assessment?
- People with diabetes, peripheral arterial disease, small arm vessels or a previous failed access.
- People with previous central venous catheters, PICCs or pacemaker leads, because these may affect central veins and future access options.
- When instructed by the care team, avoid unnecessary blood draws, intravenous lines or PICCs in the arm being preserved. Ask nephrology which arm should be protected rather than choosing a side yourself.
3.Why not wait until dialysis is urgent?
- An AV fistula needs time to mature, and some fistulas require further assessment, angioplasty or surgical revision before use.
- Earlier planning allows physical examination and ultrasound mapping of artery and vein size, course, depth and blood flow, followed by access creation at a time matched to the expected course of kidney disease.
- However, earlier is not always better. A fistula may be unnecessary when kidney function is stable, pre-emptive transplantation or peritoneal dialysis is preferred, or the expected benefit of haemodialysis is limited by overall health and personal goals.
4.Fistula, graft or catheter—which access is suitable?
- A native AV fistula may suit someone with appropriate arteries and veins and enough time for maturation, but not every fistula matures successfully.
- An AV graft may be considered when native veins are unsuitable or access may be needed sooner. Ongoing assessment for stenosis and infection is still required.
- A central venous catheter is commonly used when dialysis is urgent or no other access is immediately available and is usually considered temporary.
- The KDOQI guideline emphasizes an individualized ESKD Life-Plan. Dialysis modality, transplantation, anatomy, urgency, comorbidities and personal preferences should be considered together. An AV fistula is an important option for a suitable patient, but it is not the only correct option for everyone.
5.What happens during the first vascular access assessment?
- We review hand dominance, previous catheters, pacemaker leads, surgery and the kidney replacement plan discussed with nephrology.
- Pulses, skin, veins and circulation are examined in both arms, followed by ultrasound mapping of the arteries and veins.
- Vascular surgery and nephrology then coordinate whether an access is needed and select its type, location and timing. Access planning and starting dialysis are separate decisions.
💡 What can you do at each stage?
| Current situation | Useful next step | What it does not mean |
|---|---|---|
| eGFR around 15–20 or rising 2-year kidney-failure risk | Discuss dialysis, transplantation and conservative care with nephrology | Dialysis does not start automatically |
| Haemodialysis is likely to be a future choice | Arrange vascular-surgery review and arm-vein ultrasound | Not everyone automatically needs a native fistula |
| Small vessels or previous catheter, PICC or pacemaker | Share this history early and assess available veins and central venous outflow | Do not choose the preservation arm yourself |
| Uncontrolled fluid overload, hyperkalaemia, acidosis or uraemic symptoms | Seek prompt nephrology assessment for kidney replacement therapy | eGFR alone does not decide dialysis timing |
Frequently asked questions
Does every person with stage 4 CKD need a fistula?
No. Progression rate, 2-year kidney-failure risk, expected dialysis modality, vascular anatomy, overall health and personal goals all matter.
Does fistula creation mean dialysis will start soon?
No. Access creation prepares for possible haemodialysis. Dialysis initiation is based on symptoms, quality of life, kidney function, laboratory findings and patient preferences.
Will surgery be booked at the first visit?
Not necessarily. The first assessment usually reviews the nephrology plan and previous procedures, then examines and maps the arm vessels before timing is discussed.
Note: Planning an access does not mean starting dialysis immediately. Whether an access is needed, which type is suitable and when to create it should be decided together by the patient, nephrology and vascular surgery teams.
延伸閱讀
References
- Kidney Disease: Improving Global Outcomes (KDIGO) CKD Work Group. KDIGO 2024 Clinical Practice Guideline for the Evaluation and Management of Chronic Kidney Disease. Kidney International. 2024;105(Suppl 4S):S117–S314. 查看來源
- Lok CE, Huber TS, Lee T, et al. KDOQI Clinical Practice Guideline for Vascular Access: 2019 Update. American Journal of Kidney Diseases. 2020;75(4 Suppl 2):S1–S164. 查看來源
本文提供一般衛教資訊，不能取代個別診斷與治療。腎功能變化、透析方式、通路選擇與建立時機需由醫療團隊個別評估。
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