As the kidneys are vital organs, there is no way we survive without them are functioning minimally. When the kidneys stop working, the patient only has three options: kidney transplantation, hemodialysis or peritoneal dialysis. These three treatments are part of what we call renal replacement therapy, which, as the name implies, are treatments that seek to replace the natural kidney.
Hemodialysis (HD), a subject that we will deal with here, is therefore one of the treatment options that allow patients with severe renal impairment and irreversible can stay alive and active for several years.
This article will aim to explain to the family or to the very patient who is about to go on hemodialysis, are made as hemodialysis sessions, how long they last and what usually happens during each treatment.
Hemodialysis is a treatment used for patients with acute renal failure (ARF) or chronic renal failure (CRF). The first case occurs when a patient who previously had adequate renal function has a problem that causes their kidneys stop working for another one hour. The IRA usually occurs in cases of exogenous intoxication, use of nephrotoxic drugs, severe dehydration or urinary tract obstruction. In acute renal failure, once treated the cause, the kidneys return to function properly. Therefore hemodialysis sessions are made just as the kidneys do not recover, which usually occurs after a few days.
Have chronic kidney disease is a progressive, irreversible kidney disease. It is a kidney injury usually caused by years and years of continued aggression to the kidneys, as in cases of diabetes or high blood pressure. Patients with chronic renal failure when they arrive in advanced stages of the disease requiring hemodialysis and, except rare cases, are dependent on the machine for the rest of my life because there is no chance of recovery of renal function.
From that point, let's talk about hemodialysis in patients with chronic renal failure.
Patients with chronic renal failure who need to start hemodialysis are usually allocated in a hemodialysis clinic. Hemodialysis clinics are outpatient units, whose sole function is to offer this kind of treatment to patients.
The hemodialysis rooms usually have several machines being capable of receiving, sometimes up to 20 patients in one room. Large clinics can be 4 or 5 rooms, which allows them to dialyze patients tens of each turn.
Each patient is entitled to an armchair, which is fully reclining and contains two supports for the arm. Most of the rooms have one or more televisions so that patients can watch programs while dialyzed.
The team responsible for hemodialysis rooms consists of one or two doctors and a group of nurses.
The hemodialysis usually last for 4 hours and is carried out 3 times a week. The patient may opt for odd days (Tuesday, Thursday and Saturday) or peer days (Monday, Wednesday and Friday). You can also choose one of the three shifts of the day: morning, afternoon or evening.
Each clinic sets its time, but in general, the morning shift is made from 7 to 11 am, the 12-hour afternoon shift at 16h and 17 night shift at 21pm. Some clinics are shorter breaks between shifts and can offer a 4th shift, which usually starts at 20h and end at midnight.
The younger patients still active professionally tend to prefer the night shift while the elderly usually do their HD session in the morning shift.
The patient should remain fixed in the chosen shifts and days, but in individual cases it can advance order replacements hours or days.
There are already clinics that provide dialysis sessions late at night. The patient arrives at the clinic in the late evening and subjected to a longer session, 6 to 8 hours. That is, the patient 3 times a week hemodialysis in sleep while taking their clinical hemodialysis session. This HD mode seems to be unattractive, but is the one that has shown the best results regarding complications and long-term mortality rate.
Once the patient arrives at the clinic, he must wait until the nurse call you to enter the room. When authorized, the patient goes to the HD room, weigh yourself and then and sits in the chair next to the machine that is reserved for you. After a short conversation, in order to know if there is a problem or complaint by the patient, the nurse measures the blood pressure. If everything is okay, the nurse prepares to start the session.
For hemodialysis machine can do their job to clean toxins from the blood and remove excess body fluids, it must have access to the patient's blood. This is done through an arteriovenous fistula (AVF) or a central venous catheter (CVC).
Let's use the AVF as an example, as this is the preferred vascular access to perform a hemodialysis session. The fistula of the patient to be punctured by two needles, one for pulling blood into the machine direction and one for returning blood already filtered back into the patient. This means that the patient will be crushed twice whenever starting the hemodialysis session. In general, the stings are made at the same place, which creates a small tunnel, which facilitates the puncture and reduces the incidence of pain.
By logging, the extracorporeal circuit of the machine is filled with about 300 milliliters of blood from the patient, through a pump is taken into the dialysis filter, which is the structure that effectively filters the blood and removes excess liquid. For 4 hr, the patient's blood is continuously through the circuit and the filter.
The cleaning process of blood and the removal of excess water is controlled by a computer. As the dialysis patient does not urinate (or hardly urine), between an HD session and he wins another 3 kilos, it means he has accumulated about 3 liters of fluid during this period. That is, is the amount of water that the machine will pull out of the body during the 4-hour session. If the patient is little disciplined and drinking water indiscriminately from session to session, he can win 5 or 6 kilos in this range, which is a very large amount of water to be removed in just 4 hours session.
Once or twice every hour session, the patient's vital signs, including blood pressure, heart rate and body temperature are measured to make sure that everything is running well during treatment. If there is any problem, the doctor is called to the area to assess the patient. In the vast majority of the time, complications are simple, and the doctor does not need to take any aggressive action.
After 4 hours, the extracorporeal circuit HD machine is emptied and the whole blood returns to the patient. If everything is fine, the nursing staff removes a needle at a time and prompts the patient to use your fingers to press the puncture site to prevent that there is any bleeding. In general, this process takes about 5 minutes. After that time, the nursing staff makes sure that the puncture site no longer presents a risk of bleeding and cover with a bandage.
Blood pressure is measured again, and if all is well, the patient is free to go to your house. Before leaving, she weighs up to confirm the removal of liquid. If the machine was programmed to remove 3 liters of water, the patient needs to get out of HD with about 3 kilograms unless entered.
