A healthy human being has two kidneys. These are bean-shaped organs located in the rear abdominal cavity, left and right of the spine, slightly beneath the diaphragm under the rib cage, with the left kidney sitting behind the spleen and the right one behind the liver.
Each kidney is encapsulated by a solid cover of connective tissue (renal capsule) and embedded in further layers of fat and connective tissue, which protect the organ from trauma and anchor it to the rear abdominal wall
The inner organ can be divided into three major parts: the outer renal cortex, the inner renal medulla and the renal pelvis in the area of the hilum.
The kidney tissue (parenchyma) contains about one million little filter units, the so-called nephrons. These nephrons filter the blood and produce the urine. Each nephron consists of a so-called renal corpuscle followed by a tubule.
Together, corpuscle and tubule form a functional unit
Functions of the kidney-
draining the blood from metabolic waste – such as uric acid, urea (nitrogen) and creatinine – and from toxins (for example medication) by making urine that is released via the urinary tract
controlling the body’s fluid balance, thereby regulating blood pressure
controlling mineral and acid-base balance (by regulating the urine’s composition)
secreting hormones, such as erythropoietin for stimulating the production of blood cells, and renin for regulating blood pressure
excretion of peptide hormones
A Loss of kidney function is called as kidney failure. It doesn’t necessarily mean end-stage kidney failure. Even a creatinine of 2mg/dl is called kidney failure. There are stages of kidney failure, which are determined based on the glomerular filtration rate.
A commonly used formula called as Cockcroft gault formula or MDRD helps determine the estimated GFR (Glomerular Filtration Rate). Kidney failure is staged as follows based on the GFR.
Signs and symptoms of chronic kidney disease develop over time if kidney damage progresses slowly. Signs and symptoms of kidney disease may include:
In the presence of symptoms that can lead to suspicion of kidney disease, your doctor can do very simple tests to check for kidney disease:
Measure the level of serum creatinine in your blood to estimate your glomerular filtration rate (GFR)
Measure the level of protein in your urine (increased levels of protein show your kidneys are not working right)
Check your blood pressure.
Unlike Acute Kidney Injury (AKI), Chronic Kidney Disease (CKD) is a progressive disease. If diagnosed at an earlier stage, there are means to slow down the speed of worsening of your kidneys. This may be achieved by the following means-
1. Good control of your Blood Pressure.
2. Good control of blood sugar levels.
3. Restriction of protein in the diet along with a medicine called alfa-ketoanalogue.
4. Avoid drugs causing damage to your kidneys-such as painkiller tablets/injections and certain antibiotics. Even certain ayurvedic and herbal medicines may damage your kidneys.
5. Avoid getting dehydrated.
Despite all measures, your kidneys may reach end stage renal failure someday – when your nephrologist has no option but to offer you some form of renal replacement therapy.
Renal replacement Therapy – Renal replacement therapy comprises either transplantation or dialysis. Some people decide not to receive renal replacement therapy but choose conservative management, which comprises full supportive management (including advance care planning and control of symptoms and complications.
What you need to know:
Chronic kidney disease (CKD) is a progressive disease-the progression of which can be retarded with suitable measures. They include-
1. Good control of blood pressure and blood sugar.
2. Avoiding medications that could potentially harm your kidneys further.eg. painkillers, ayurvedic medications, etc.
3. Avoiding dehydration.
4. Controlling the protein intake in your diet esp. red meat.
5. Ask your doctor regarding role of alfaketoanalogues in retarding the progression of CKD.
It should be understood that progression of CKD cannot be halted but retarded and the patient is going to need some form of Renal Replacement Therapy (RRT) after a few years.
Dialysis is started when the estimated Glomerular Filtration Rate (eGFR) is below 10ml/m in non-diabetics and below 15ml/m in case of diabetics. However, it’s just not the figures that matter. The clinical symptoms of the patient-presence of breathlessness, swelling over the body, low appetite, vomiting and other uremic symptoms may warrant early dialysis.
If hemodialysis is chosen, then a pre-emptive arterio-venous fistula as a suitable vascular access is constructed when the eGFR is around 20ml/min. If an AV fistula is not done pre-emptively before the start of dialysis, then the nephrologist needs to insert a dialysis catheter through the vein in the neck or the groin. These are however temporary vascular accesses and for a patient choosing to remain on dialysis may still need to undergo an AV fistula surgery as a permanent venous access.
Hemodialysis is a treatment to filter wastes and water from your blood, as your kidneys did when they were healthy. Hemodialysis helps control blood pressure and balance important minerals, such as sodium, potassium and calcium in your blood.
Hemodialysis can help you feel better and live longer, but it’s not a cure for kidney failure.
During hemodialysis, your blood goes through a filter, called a dialyzer, outside your body. A dialyzer is sometimes called an “artificial kidney.”
At the start of a hemodialysis treatment, a dialysis nurse or technician places two needles into your arm. You may prefer to put in your own needles after you’re trained by your health care team. A numbing cream or spray can be used if placing the needles bothers you. Each needle is attached to a soft tube connected to the dialysis machine.
The dialysis machine pumps blood through the filter and returns the blood to your body. During the process, the dialysis machine checks your blood pressure and controls how quickly
blood flows through the filter
fluid is removed from your body
The actual process of movement of urea, creatinine and electrolytes from the blood to the waste water happens in the filter, also called as the dialyzer.
Hemodialysis can replace part, but not entire kidney function. Hence a patient still needs to restrict fluids, phosphorus and potassium in the diet; plus take anti-hypertensive medications and erythropoietin injections.
The optimum frequency of dialysis is debatable. Most patients are advised to take thrice a week hemodialysis. However, a few may need even more depending on the need to take care of extra fluid in the body. Short daily sessions are the new norm in western countries which help the patients remain healthy and fit.
Most patients wish to reduce dialysis sessions done in a week for logistics or financial reasons. However, it is in the best interest of the patient that he continues dialysis at a minimum of 2-3 sessions per week because it is the better toxin removal that helps get them to a healthy state. Reducing dialysis will worsen the uremia and in turn reverse all the good work done until then.
Staying fit and healthy on dialysis is not a rocket science at all.
A few important points which help a good healthy life, while on dialysis are as follows-