In most cases, your drinking restrictions will be lifted after transplantation. This means that you can and should drink normally again. Despite this newfound freedom, you drinking quantity is still important after transplantation. In this article, you will learn why your drinking quantity is important and how to keep an eye on it.
When you receive a new kidney and it works properly, it is also responsible for urine production. It filters excess minerals and toxins from the blood and then removes them from the body through urine. In this way, your new kidney prevents waste products and excess water from remaining in your body. Likewise, it protects your body from water retention (=edema) or high blood pressure.
Before your transplant, dialysis partly took over this job. Since hemodialysis removed water from your body only selectively (e.g. every 2 days), you probably had significant restrictions on how much fluid you could drink. The good news is that if your new kidney is working properly, there is usually no restriction on how much you can drink after the transplant!
How does my new kidney produce urine?
Unlike your old kidneys, your new kidney was probably placed in the area called “small pelvis” during surgery. This is also where your urinary bladder and rectum are located. The advantage of this spot is that it is easier access during surgery. Also, your new kidney can be connected directly to your pelvic vessels there. In other words, it will be connected to your bloodstream via the pelvic arteries to clean your blood.
After your blood has been cleansed by your new kidney, it flows back into your bloodstream through your pelvic vein. But what happens to all the urine that your new kidney has filtered out of your blood? During your transplant surgery, the surgeon will connect your ureter to your new kidney. This connects your new kidney to your bladder which allows the urine to flow out again and be excreted as usual.
How much should I drink now?
It is not possible to make a general statement about how much you should drink after transplantation. This often depends on the time after the operation, the function of your new kidney and your urine output. The exact amount you should drink after the transplant is therefore always determined by your transplant team. If you have any questions or uncertainties, you can always discuss them with your medical team. Often the prescribed amount to drink after transplantation - with normal kidney function - ranges between 2 and 3 liters per day.
What role does my excretion play?
In order for you to be able to drink again without restriction, your kidney should function properly. In the period shortly after the transplant, your new organ often needs some time to properly acclimatize to its new workplace. As such, during this period, your urine output may still be a little low.
If there are any doubts, your new kidney will be supported short-term by dialysis. So don't worry if you need to go on dialysis again after the transplant. This is only to protect your new kidney. To keep an eye on the function of the transplant, regular laboratory checks are carried out immediately after the operation. Kidney function is primarily reflected in the estimated glomerular filtration rate (=eGFR) and your creatinine level. Your eGFR indicates how much blood your new kidney cleans per minute - the higher your eGFR, the better your kidney is working. To calculate the eGFR, the levels of creatinine in your blood are measured. Creatinine is a byproduct of the energy production cycle of your muscles. The better your new kidney cleans your blood of waste products, the lower your blood creatinine levels will usually be.
In addition to your lab values, your urine output will be monitored. For this purpose, your medical team prepares a so-called balance sheet. In this balance sheet, your fluid intake is compared with your fluid excretion. If your fluid intake is high, your urinary excretion should naturally also be higher, and vice versa. Only if this interplay works, your kidney is able to keep your water balance in equilibrium. How exactly the balance works and what values you should pay attention to, you will also learn in the other articles of the Mizu App.
What does science say?
The ideal drinking quantity after transplantation has been investigated in numerous studies to date. In particular, normal drinking amounts of about 2 liters per day were compared with high drinking amounts of more than 3 to 4 liters per day. An examination of these studies showed that a very high drinking quantity, compared to the normal drinking quantity, has no further positive effect on the survival and function of your new kidney.
Therefore, many transplant centers have guidelines that range from 2 to 3 liters per day. The idea that a high fluid intake is necessary to flush your new kidney and keep it fit is just a myth. It's just important that you don't drink too little fluid and that you stick to the target corridor given to you by your medical team.
What are the targets for healthy people?
In comparison, drinking recommendations for healthy people are usually calculated based on their body weight. Between 19 and 50 years of age, a daily fluid intake of 35 ml/kg body weight is recommended. From the age of 65, this is 30 ml/kg body weight per day. For a 70 kg adult, this corresponds to a daily fluid intake of just over 2 liters. These values therefore coincide relatively well with the minimum limit for transplant recipients.
What beverages are appropriate after transplantation?
After transplantation, the principles of a low-bacteria diet apply. This is necessary to protect your body from infections during the suppression of your immune system by your medications. You need this immunosuppression to protect your kidney from being rejected by your own immune system.
The principles of a low-bacteria diet also apply to your drinks. Simple tips that can help you do this include:
- It's best to always drink from your own bottle and your own glasses. You should store bottles in a cool and dark spot after opening.
- Tap water should only be drunk fresh and cold. Filters or Sodastreams should be avoided. Water from beverage dispensers is also not a good idea, because who knows how long it has been there.
- Coffee and tea are best drunk freshly brewed or from a regularly cleaned machine. Tea should be made with boiling water.
- Juices should be drunk fresh or home-squeezed whenever possible. Water is better for your post-transplant health than sweetened juices, as you should also keep an eye on your weight.
In any case, you should avoid St. John's wort tea and grapefruit juice. These two drinks can affect the action and elimination of your medications that help protect your new kidney (especially the immunosuppressants).
How do I keep track of how much I drink?
To keep track of how much you drink, you can keep a so-called drinking diary. This is available in electronic form or in the form of apps, such as the Mizu app. It is important that you know how much liquid is in the jars and bottles you use at home. This way, you can easily document the amount you drink in your diary and share it with your transplant team.
