From Dr Daniel Lin, Renal Physician, CMDHB

Renal Replacement Therapies (RRTs)
腎臟替代療法

RRTs are treatments for people whose kidneys have failed almost totally to work as a cleaning organ in the body. Their aim is to replace what native kidneys do normally, so toxins and extra body water can be excreted from body. RRTs include two main groups: Dialysis and kidney transplantation.
當腎臟病病程進入末期腎衰竭時，亦即腎功能不及正常的十分之一，血液中之尿毒指數不斷攀升，尿毒症狀慢慢產生，而且藥物及飲食控制已無法延長疾病之進展，就需要選擇一種適合自己的腎臟替代療法，來代替腎臟工作。目前腎臟替代療法計有血液透析、腹膜透析及腎臟移植三種，依病況可供選擇。

What is dialysis? 什麼是透析？

Dialysis is a way of replacing kidney function by using a filter membrane ( either native or artificial) to clean blood and filter out toxins, wastes, and extra body water that produced by normal metabolism. It is important to know that it does not treat the kidneys, which means, it will not improve the original kidney function.
透析是利用過濾膜（人體本身或人工）清潔血液和過濾掉毒素、廢物、以及正常代謝產生的多餘的水的換腎功能之方式。重要的是要知道，透析並沒有治療腎臟，這意味著：它不會提高原腎功能。

Who needs dialysis? Is dialysis absolutely necessary? When to start? Do I need dialysis life-long once started?
誰需要透析？透析是絕對必要的？什麼時候開始？一旦開始之後，是否需要透析終生？

In general, people who have severe chronic kidney disease (stage 5) with either glomerular filtration rate (GFR) below 10 ml/min or symptoms of uraemia will need to be started on dialysis. However, it also subjects to other factors, such as people’s wishes and preference, functional capacity, and other medical conditions that may subject dialysis to cause more harm.
一般情況下，若是有嚴重的慢性腎臟病（ 5級），無論是腎小球濾過率（GFR）低於10毫升/分鐘，或是有尿毒症的症狀（當病人呈現尿毒症狀 ： 噁心、嘔吐、食慾不振、皮膚搔癢、呼吸困難、四肢及心肺積水、口腔有異味），亦即腎功能不及正常的十分之一等情形，都會建議開始接受透析治療。然而，也有其他因素需要考量，如個人的意願和喜好，病人平時的自理能力，和其他可能使透析造成更多傷害的醫療病史。

Dialysis is necessary to prolong life when kidney function fails completely. People who have end stage kidney failure will only have few weeks to months to live if dialysis is not started promptly. People started on dialysis in average will have 5 or more years to live depending on other medical conditions. People on dialysis die later mostly not due to dialysis itself, but due to heart attack, stroke, and infections. These are mainly caused by their underlying health problems such as diabetes and high blood pressure. Again, dialysis is life-saving.
當腎功能不及正常的十分之一等情形、腎臟是無法維持生命，透析是必要的。如果透析不及時開始的話，終末期腎功能衰竭的病人通常只會有幾週到幾個月的生命。根據其他醫療條件，一般病人在開始透析之後，都有平均 5 年或以上的生命。這些病人後來的死因大多不是由於透析本身，而是由於心臟發作，中風和感染。這些主要是因為他們的潛在的健康問題，如糖尿病和高血壓。透析是救命的腎臟替代療法。

The decisions on the timing of starting dialysis are normally made by kidney physicians in conjunctions with patient’s understanding and agreement. It is important to understand the concept of dialysis and start the process of preparing for dialysis way before the time comes. The entire process of preparation for dialysis may take up to few months. This process include patient education, medical and psychological assessment, choosing type of dialysis, and dialysis access formation. Although dialysis can be started urgently without this process via a neck line, but the fact is that people who had planned dialysis do better and have less complications compared to those who started urgently.
開始透析的時間，通常是由腎臟醫師與病人進行協議而決定。病人必須事先了解透析的概念，並開始準備透析的方法，這是非常重要的。準備透析的整個過程可能需要長達數個月。這個過程包括病人教育、醫療和心理評估、透析所選擇的類型、和透析通路的安裝。透析雖然可以通過頸部線條緊急啟動。但事實是，透析準備計劃做得好的病人通常較少有並發症。

Once dialysis is started, almost all will need it life-long. It has a huge impact on people’s daily activity, family, occupation, finance, and mental health. People will need lots of support from family, social services, and health professionals. Kidney department in Hospital can provide most of supports for difference aspects.
透析一旦開始，幾乎都是病人一輩子的。這對病人們的日常活動，家庭，職業，財務和心理健康都可能產生巨大的影響。病人們將需要大量的支持，家庭，社會服務和衛生專業人員。腎科醫院可以為病人提供各方面的支持。

There are other indications for start on dialysis such as severe acute kidney injury, poisoning, or some haematological malignancies and conditions. In most of these cases, dialysis is temporary until the kidney function returns.
還有其他少數病情需要透析治療，例如：嚴重急性腎損傷，中毒，或一些惡性血液病例。對於這些病人，大多數情況下，透析是暫時的，直到腎功能回復正常。

How to do dialysis? Are there different types of dialysis? 如何做透析？有不同類型透析？

There are two main type of dialysis: Haemodialysis and Peritoneal dialysis.
有兩種主要類型的透析方式：血液透析和腹膜透析。

Haemodialysis (HD) uses an artificial membrane filter to clean blood. It needs blood to be transported out of body into the filter for cleaning before returning to the body. It needs a large blood vessel access such as an arteriovenous fistula (AVF) or a large venous catheter to transport large volume of blood per minute for cleaning. Once started, most of people will need 3 sessions per week, 4-5 hours per session. This can be done in a hospital or in-centre setting, or sometimes people can be trained to do it themselves at home or community houses with machine provided.
血液透析俗稱「洗血」，是利用血液透析機器及人工腎臟，進行透析治療，應用體外循環進行血液淨化。治療前先以外科手術建立動靜脈管，一至二個月後方可進行透析治療。治療時在手臂瘻管處插入兩支針頭，血液由其中一支針頭流向體外，進入人工腎臟，將身體的「毒素」和水分移除，淨化後的血液再由另一支針頭流回體內，病人每週須到透析中心進行3次透析治療，每次治療時間約需4-5小時。這可以在醫院或在洗腎中心設置來完成，或者有時人們可以訓練自己做在家裡或社區洗腎（若是有血液透析機器）。

Peritoneal dialysis (PD) uses people’s own peritoneal membrane overlying the abdominal organs as the filter. It is an effective natural filter to excrete toxins and extra water in the body. People who chose PD needs to have a tube to be inserted into their abdominal cavity. Clean dialysis fluid (normally with glucose in it) is infused into the cavity and stays in for 3-4 hours allowing toxins and extra water to be exchanged. The resultant fluid in the cavity (dirty fluids) is then drained out before another clean bag is infused in. In general, people need to do 4 exchanges a day. In between exchanges, PD patients are able to carry on with their normal activities. Instead of being attached or hooked to a machine for hours 3 times a week like in haemodialysis, PD provides more freedom and all can be done in the community with minimal hospital contact.
腹膜透析俗稱「洗肚子」，腹膜是腹腔內一層包覆在內臟器官的薄膜，有豐富的微血管分佈，腹膜透析就是利用腹膜作為過濾、排除體內水分及廢物的一種方式，乃利用人體的腹膜作為半透膜，藉由進入肚子的透析液將身體過多的水分及代謝廢物進行移除。首先需在腹腔內植入一條永久性導管，經由導管將透析液灌入腹腔存留一段時間，將體內廢物及水分移除至腹腔內的透析液中，再引流出來，且透析液留置在腹腔內的時間，平均約 4 至 6 個小時，在這段時間，行動不受限制，可以做自己想做的事， 4 至 6 小時後，再重複換液，每天依醫囑進行數次換液，換液的時間和地點，可依日常生活作息調整。換液場所可以選擇在家裡、辦公室或其他常去且密閉之空間，換液環境必須符合特定的條件，以避免受到感染。

The choice of dialysis modality is dependent on individual circumstances and largely people’s choice to suit their life style. There are limited data suggesting which one is better or worse, and they can be inter-changed when situation changes.
透析方式的選擇取決於個人情況，在很大程度上是依據病人的選擇以滿足他們的生活方式。目前的研究只有有限的數據，並無法結論出哪一種方式較好。

What are the side effects of dialysis? 透析的副作用？

Although dialysis is an artificial way of mimicking what normally good kidneys will do, it does not replace all functions of kidneys. Hormones such as vitamin D and erythropoietin that are processed or secreted by kidneys are not produced by dialysis. People need medications to replace these hormones while they are on dialysis.
雖然透析是模仿腎臟功能的一種人工方式，它並不能代替腎臟的全部功能。由腎臟加工或分泌的激素（如維生素 D 和促紅細胞生成素）是不會因為透析過程而產生的。透析治療的病人需要透過藥物來攝取這些激素。

Dialysis itself may also create side effects or complications. These include bleeding due to clotting disturbance, low blood pressure, stress to heart causing irregular heartbeats, stroke, infections, cramps, nerve damage, immune system suppression, skin changes and calcium deposition, etc. Most of complications only develop after years of dialysis.
透析本身也可能產生副作用或並發症。這些包括因為凝血障礙而造成的出血，低血壓，對心臟壓力而造成的心律不齊，中風，感染，痛性痙攣，神經損傷，免疫系統抑制，皮膚的變化和鈣沉積等。多數並發症只會在經過多年透析的治療之後才會產生。