Dialysis Overview

Our kidneys regulate body levels of water and minerals, and remove waste products. The kidneys also produce hormones like renin, erythropoietin and 1, 25-dihydroxycholecalciferol.

Dialysis is a life-saving treatment for kidney failure. It helps remove nitrogenous waste, extra fluid and minerals from the blood when kidneys can no longer function adequately.

Dialysis may be used in two main situations:

• Acute kidney injury (AKI): This is sudden onset kidney problem happening over hours or days. Some people need dialysis for a short time while their kidneys recover.
• End stage kidney disease (ESKD) or chronic kidney disease stage V (CKD V): This is the last stage of a progressive kidney disease (eGFR is less than 15).

Dialysis is of two types:

•     Haemodialysis
•     Peritoneal Dialysis

Dialysis is recommended when waste, fluid, potassium or acid accumulates in the body and cannot be managed safely with medicines, dietary changes or other treatments. It also depends on persistent/ worsening symptoms such as nausea, vomiting, loss of appetite, weight loss, itching, swelling, breathlessness, tiredness or confusion etc

 

HEMODIALYSIS

Hemodialysis is a technique whereby the patient’s blood is processed in special filters (dialysers) where they are exposed to a specially created fluid (dialysate) against a semipermeable membrane; thus helping to filter out the waste products from the blood via the process of diffusion. The process of removal of excess fluid from the body is known as ultrafiltration. Both processes happen simultaneously, the processed blood is then returned to the patient’s body. Each session lasts approximately 4 hours and International guidelines recommend at least 12 hrs of treatment per week.

 

Image source: National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)

Access

In order to do hemodialysis, your care team needs a safe way to reach your blood - vascular access or dialysis access.

A V Fistula: A connection is made between an artery and a vein in the hand or arm. This is the preferred access because of minimal complications.

A V Graft: An artificial vein is used to connect an artery and a vein, usually in the arm. It may be associated with complications like thrombosis, stenosis etc

Catheter: A tube made of inert material is placed in a large vein, often in the neck, chest or groin. This may be used when dialysis needs to start quickly or while waiting for a fistula or graft to be ready. In some cases when a fistula or graft is not feasible a cuffed tunnelled catheter may be used as a long term access. Complications include infections, stenosis, thrombosis and loss of major veins.

Intradialytic complications

• Sudden fall in blood pressure
• Muscle cramps
• Headache
• Nausea
• Dizziness or weakness
• Feeling very tired after treatment
• Bleeding or bruising near the access
• Infection or blockage in the access·

Take care of your access

Report to the dialysis unit immediately in case of

• Bleeding from access site that will not stop
• Severe pain, swelling, redness, warmth, or drainage near your access
• A fistula or graft that stops buzzing or vibrating like usual

 

PERITONEAL DIALYSIS

Peritoneal dialysis relies on use of inner lining of the abdomen – known as peritoneum, to filter blood inside the body. A specially created dialysis solution—water with dextrose and other additives—flows from a bag through a catheter into the abdominal cavity.  This dialysis solution absorbs wastes and extra fluid from the body. After a few hours, the solution and the waste are drained out the abdomen into an empty bag and a fresh bag of dialysis solution is instilled. This process is called an exchange.

 

 

Image source: National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)

Access

A few weeks before the planned start of peritoneal dialysis, a specially designed catheter is surgically placed in the abdomen often below and a little to the side of the belly button.

Types of peritoneal dialysis

• continuous ambulatory peritoneal dialysis (CAPD)
• automated peritoneal dialysis (APD)

CAPD

Exchanges are done manually in a clean, well-lit place. Each exchange takes about 30 to 40 minutes. The solution in left in the abdomen for 6 to 8 hours - the dwell time. Generally, 3 exchanges per day are required. Each CAPD exchange takes about 30 minutes to perform and can be timed to be done around scheduled breaks for lunch etc.

APD

Exchanges are done with the help of a machine called the cycler. It fills and empties the abdomen three to five times during one cycle. Automated peritoneal dialysis can be done at night. Before going to sleep the cycler is connected and then disconnected the next day morning.

Complications

Possible problems from peritoneal dialysis include infection, hernia and weight gain.

One of the most serious problems related to peritoneal dialysis is infection. Infection can involve the skin around catheter exit site or can develop peritonitis. Bacteria can enter through your catheter during connection or disconnection.

Dialysis training

Patients and at least one family member or friend are trained to do exchanges and avoid infections. This takes about a week to 10 days and then most people can perform both types of peritoneal dialysis on their own. Training includes the correct way to connect & disconnect, assessment of UF volume, care of skin around the catheter - exit site, prevention of infections, watching out for potential complications etc. Both CAPD and automated peritoneal dialysis can be performed in any clean, private place, including at home, at work or when travelling.

 

Comparison

• Hemodialysis is often done in a health care setting, such as a dialysis centre or hospital. Peritoneal dialysis can be done at home, work or in any other space that is clean and dry. Therefore it is beneficial for people who have a job, travel or live far from a hemodialysis centre.
• Peritoneal dialysis is a more continuous therapy than hemodialysis and leads to less potassium, sodium and fluid accumulation in the body. This allows a more flexible diet and fluid intake pattern than hemodialysis.
• Better preservation of residual renal function in patients on peritoneal dialysis.
• Since there is no need for puncturing the fistula with needles before each dialysis sessions, there is no pain associated with peritoneal dialysis. 

 

Dialysis Adequacy

With good quality dialysis there will be improvement in symptoms such as increased appetite, better quality of sleep, no breathlessness, no swelling, feeling energetic and overall better quality of life. People on dialysis can continue to work, go to school, care for family and continue other daily activities.

In addition, there are clinical markers indicating good quality dialysis including better blood pressure control, minimal interdialytic weight gain, maintained levels of haemoglobin, potassium, phosphorus, albumin etc. Certain parameters like URR, kt/v are studied for Hemodailysis adequacy and PET and clearance studies are done to assess adequacy of Peritoneal dialysis.

 

Dialysis is a form of renal replacement therapy. Dialysis can replace some functions of healthy kidneys, but it does not cure your kidney disease. It is also important to understand that dialysis does not replace the endocrine functions of failed kidneys. Therefore, patients need to take additional medications and precautions as well.

 Dialysis is a bridge to kidney transplant.

 Talk to your treating team for individualised advice.

Kidney Transplant - An Introduction

▶️ Watch Dr Anupam Roy Explain about Kidney Transplant

Organ Donation Awareness

Kidney transplant is the treatment of choice in End Stage Renal Disease (ESRD) or Chronic Kidney Disease Stage 5 (CKD V). Compared to dialysis, survival is better after transplantation. This advantage is irrespective of age, sex, gender, ethnicity and with diabetic or non-diabetic kidney disease.

Herrick twin brothers were the world's first successful kidney transplant pair. The transplant was carried out by Dr Murray on December 23^rd 1954, at The Peter Bent Brigham Hospital Boston USA. In India first successful renal transplantation was done in 1971 in Vellore.

A kidney transplant is a surgery in which a healthy kidney from a donor is placed into the body of a patient whose own kidneys are no longer working properly. The new kidney takes over filtering waste, removing extra fluid and helping the body maintain balance.

In most kidney transplants, the patient's own failed kidneys are not removed — they are left in place. The donated kidney is placed in the lower abdomen, close to the bladder.

Benefits of Kidney Transplant

A successful transplant offers many benefits compared to long-term dialysis:

Better energy levels and appetite

Freedom from regular dialysis sessions / hospital visits

Fewer food and fluid restrictions

Better ability to work, study, travel and spend time with family

Improved emotional well-being and mental health

Better long-term survival outcomes

 

Who Can Get a Kidney Transplant?

Not every patient with kidney failure is automatically suitable. The transplant team conducts a thorough evaluation to check whether the patient can safely undergo surgery and take lifelong medicines afterwards.

The evaluation considers:

Heart health and overall fitness for surgery

Diabetes control and blood pressure management

Absence of active serious infections

Cancer history, reviewed where relevant

Liver/ chest condition

Weight and nutritional status

Blood group and tissue compatibility with the donor

Reliability in taking medicines on time

Family, emotional and financial support available

 

Tests and Evaluation Before Transplant

Before a transplant, both the patient and the donor require detailed evaluation. These tests help doctors minimise risks and plan the safest treatment.

Blood group

Haemoglobin, Kidney function tests including electrolytes, Urine tests

Blood pressure, diabetes and heart health checks

Imaging for kidney structure / function/ blood supply

Infection screening (viral, bacterial)

Cancer screening where indicated by history

Tissue matching and crossmatch tests

Psychological and social support review

For deceased donor transplant, patients are evaluated first and then placed on a waiting list if found suitable

In case of transplant across incompatible blood groups further testing including isoagglutinin antibody titres is done

 

Donor Evaluation and Safety

Many families worry about whether the donor will be safe. A donor is never accepted simply because the family is willing. Doctors first carefully check whether donation is truly safe for the donor. The donor's safety is considered equally as important as the transplant recipient's success

• A donor must be medically fit and emotionally prepared before donation is approved

• Donation must be completely voluntary and free from pressure or coercion

• Doctors explain all surgical risks, recovery expectations and long-term precautions to the donor

• Most healthy, well-evaluated donors live entirely normal lives with one kidney

• Donors are advised to continue periodic health check-ups after donation

 

Life After Transplant

After a kidney transplant, patients must take anti-rejection medicines (immunosuppressants) every day, for life. In addition regular check-up including blood & urine tests are done to check kidney function. The following precautions are recommended:

Take medicines exactly as prescribed — same time every day

Never skip a dose, even when you feel completely well

Never stop or change medicines without consulting your transplant doctor

Attend all follow-up appointments and blood tests on schedule

Inform your team before starting any new medicine, herbal product or supplement

Carry your medicine list at all times and keep spare supplies when travelling

 

High Creatinine: How to interpret?

Creatinine is a waste product of muscle breakdown. It is removed from the blood through your kidneys and high levels can signal kidney issues. This test therefore helps assess kidney function.

Some people with a “normal” creatinine levels can also have kidney disease. This is because a “normal” creatinine level can change depending on multiple factors like age, sex and body size0.

The best way to understand how well your kidneys are functioning is to look at eGFR (estimated glomerular filtration ratio) which is calculated using serum (blood) creatinine level, age and sex, height and weight.

The serum (blood) creatinine derived eGFR is used:

• To establish a diagnosis of kidney dysfunction - AKI (acute kidney injury) or CKD (chronic kidney disease)
• To classify the stage of CKD
• To monitor changes in kidney function over time in people with CKD
• To decide if any medication needs to be stopped or modification of dose

Evaluation of kidney functions includes a combination of history, clinical examination and laboratory tests.

The baseline blood tests range from CBC, blood urea/ creatinine, electrolytes (Na/K), calcium/ phosphorus/ uric acid, serum protein/ albumin etc. Urine examination involves physical examination for colour/ turbidity, chemical analysis for protein/ blood/ sugar, microscopic evaluation for WBC/ RBC/ Casts/ Crystals etc and urine culture. Radiological studies include USG, X Ray, CT scan & Radionuclide scan. Specialized tests like iPTH, iron studies and serological/ immunological tests may also be required depending on associated illness.

Kidney biopsy may be indicated in certain situations. It is a bedside procedure done under L/A using real-time USG guidance. Tissue is examined after staining with special stains.

Therefore only looking at a creatinine level is not the best way to completely understand kidney health.

 

Chronic Kidney Disease - An introduction

▶️ Watch Dr Anupam Roy Explain about Chronic Kidney Disease (CKD)

How to Detect CKD

CKD Causes & symptoms

Stages of CKD

 Precautions for patients with CKD

Chronic Kidney Disease (CKD) is a progressive, irreversible decline in kidney function occurring over months to years. Globally, CKD affects nearly 10–15% of adults. In India, prevalence estimates range from 8–12%.

Definition and Classification: CKD is defined as abnormalities of kidney structure or function present for more than 3 months.

Classified into 5 stages based on

a. Glomerular Filtration Rate (GFR): G1 to G5, with G3 split into 3a and 3b

b. Subcategorized according to the spot urinary albumin-creatinine ratio : 3 levels of albuminuria (A1, A2, and A3), with each stage of CKD

CKD classification also recommends specifying the cause of CKD (e.g., diabetic nephropathy, hypertensive nephrosclerosis)

Etiology

Diabetes Mellitus (Diabetic Nephropathy)

Hypertension (Hypertensive Nephrosclerosis)

Glomerulonephritis

Polycystic Kidney Disease

Obstructive Uropathy

Prolonged use of nephrotoxic drugs (NSAIDs, certain antibiotics)

Risk factors:

Age >60 years

Family history of CKD

Cardiovascular disease

Obesity and metabolic syndrome

Smoking

Recurrent urinary tract infections

Low birth weight (predisposing to reduced nephron number)

 

Pathophysiology: CKD results from chronic and sustained insults leading to a gradual loss of functioning nephrons. The remaining nephrons undergo hyperfiltration to compensate, which increases intraglomerular pressure. This intraglomerular hypertension in turn leads to increased glomerular permeability and filtration resulting in proteinuria. Increased tubular resorption of protein results in tubulointerstitial inflammation & fibrosis. Over time, this leads to glomerulosclerosis, tubulointerstitial fibrosis, vascular sclerosis and further nephron loss - a vicious cycle culminating in end stage kidney disease (ESKD).

 

Clinical Features:

CKD often remains asymptomatic until advanced stages. Symptoms do not appear till more than 50% kidney function is lost.

Early (nonspecific) manifestations:

Fatigue and malaise

Loss of appetite/ Nausea or vomiting

Nocturia or polyuria

Mild edema

Late manifestations:

Generalized swelling

Shortness of breath

Generalised Pruritus

Cardiovascular manifestations- Arrhythmias, Ischaemic heart disease.

Bone pain or fractures (renal osteodystrophy)

Cognitive impairment or drowsiness (uremic encephalopathy)

 

Diagnosis:

CKD is diagnosed through a combination of laboratory tests and imaging studies.

Laboratory Evaluation:

a.       Serum Creatinine and eGFR: cornerstone for staging kidney function.

b.       Urinalysis: to detect protein, sugars, RBC, WBC or casts

c.       Urine Albumin Creatinine Ratio (UACR): quantify albuminuria, an early marker.

d.       Serum Electrolytes: Na, K, Ca, Phosphorus

e.       iPTH, Sr HCO^3-

f.         Hemoglobin

g.        Lipid profile: to assess metabolic risk factors

h.       HbA1c: to assess degree of blood sugar control.

Imaging Studies:

a.       Ultrasonography: to check size, alteration in echogenicity & corticomedullary differentiation, to detect obstruction etc.

b.       CT/MRI: in selected cases to evaluate structure or vascular causes.

Renal Biopsy: Indicated when the cause is uncertain or glomerulonephritis is suspected.

 

Complications: CKD is a systemic disorder with multiple complications:

1.       Cardiovascular disease: present in approx. 75% patients.

2.       Anemia

3.       Mineral and Bone Disorder (CKD-MBD

4.       Metabolic acidosis

5.       Electrolyte disturbances: hyperkalemia, hyperphosphatemia, hypocalcemia.

6.       Fluid overload

7.       Uremic complications: pericarditis, encephalopathy, neuropathy.

 

Management: The goals of CKD management are to treat the underlying disease, slow disease progression, treat complications, and prepare for renal replacement therapy.

Treat the Underlying Cause:

1.       Glycemic control: maintain HbA1c <7%.

2.       Blood pressure control: target <130/80 mmHg.

3.       Control of proteinuria

4.       Avoid nephrotoxic drugs: NSAIDs, contrast agents, and certain antibiotics.

Lifestyle Modifications:

1.       Dietary salt restriction (3-5 g/day).

2.       Moderate protein intake (0.8 g/kg/day).

3.       Maintain ideal body weight.

4.       Avoid smoking and alcohol.

5.       Encourage regular physical activity.

Prepare for Renal Replacement Therapy: Options include

1.       Hemodialysis,

2.       Peritoneal dialysis

3.       Kidney transplantation

 

Prognosis: The prognosis depends on the stage at diagnosis and control of underlying conditions. Earlier diagnosis helps prevent further damage to kidneys and also slow down progression of disease. Patients with well controlled diabetes and blood pressure can stabilize for years. Newer medications to slow progression of kidney damage can help improve outcomes. In patients with End Stage Kidney disease kidney transplant is the renal replacement therapy of choice.