BSc MB BS BDS FDSRCSEng MRCS LRCP DRCOG...
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nhsManagers.net | Briefing | 14 April 2018 Medicine for Managers Dr Paul Lambden BSc MB BS BDS FDSRCSEng MRCS LRCP DRCOG MHSM FRSM The kidneys are bean-shaped structures located in the upper part of the abdomen behind the lining (peritoneum) of the abdominal cavity. Amazingly, each healthy kidney contains about one million nephrons. Each nephron is a functional filtration unit. Unfiltered blood from the arterial system enters through a knot of small vessels and the pressure in the vessels forces water and small molecules from the blood vessels and into the tubular nephron. The water passes down the tube. Required molecules are cleverly reabsorbed into the blood and the remaining water and unwanted molecules (such as urea) pass from the nephron into a collecting system which carries what is then urine into the bladder where it can be passed. In a healthy young adult the kidneys filter about 130 millilitres of water per minute which equates to about 180 litres (or about 40 gallons) a day. Kidney disease leads to the progressive loss of nephrons which die off and this gradual loss of kidney function is called chronic renal (kidney) failure. In the early stages of chronic renal failure, there are few, if any, symptoms but the ability of the kidney to filter out unwanted products and to retain essential chemicals is gradually compromised. Doctors can do a simple blood test from which an eGFR (estimated Glomerular Filtration Rate) can be derived. It is mathematically derived from results obtained through the measurement of a serum waste product called creatinine and adjusted for age, sex and race. The normal eGFR is between 90 and 120 ml/ min for an average build patient. If the figure drops below 60 ml/min for a period of three months, it indicates kidney deterioration and renal failure. Signs and symptoms of chronic renal failure are initially insidious and include progressive features such as: • Loss of appetite and nausea • Fatigue and weakness Kidney (Renal) Failure There are two kidneys of which the principal role is the elimination of waste material and the regulation of the volume and composition of body fluid. They provide, in fact an active filtration system, filtering out from the blood a variety of molecular components and selectively reabsorbing the elements of the filtrate which must be kept.
Transcript of BSc MB BS BDS FDSRCSEng MRCS LRCP DRCOG...
nhsManagers.net | Briefing | 14 April 2018
Medicine for Managers
Dr Paul Lambden BSc MB BS BDS FDSRCSEng MRCS LRCP DRCOG MHSM FRSM
The kidneys are bean-shaped structures located in the upper part of the abdomen behind the lining (peritoneum) of the abdominal cavity.
Amazingly, each healthy kidney contains about one million nephrons. Each nephron is a functional filtration unit. Unfiltered blood from the arterial system enters through a knot of small vessels and the pressure in the vessels forces water and small molecules from the blood vessels and into the tubular nephron. The water passes down the tube.
Required molecules are cleverly reabsorbed into the blood and the remaining water and unwanted molecules (such as urea) pass from the nephron into a collecting system which carries what is then urine into the bladder where it can be passed.
In a healthy young adult the kidneys filter about 130 millilitres of water per minute which equates to about 180 litres (or about 40 gallons) a day.
Kidney disease leads to the progressive loss of nephrons which die off and this gradual loss of kidney function is called chronic renal (kidney) failure. In the early stages
of chronic renal failure, there are few, if any, symptoms but the ability of the kidney to filter out unwanted products and to
retain essential chemicals is gradually compromised.
Doctors can do a simple blood test from which an eGFR (estimated Glomerular Filtration Rate) can be derived.
It is mathematically derived from results obtained through the measurement of a serum waste product called creatinine and adjusted for age, sex and race.
The normal eGFR is between 90 and 120 ml/min for an average build patient. If the figure drops below 60 ml/min for a period of three months, it indicates kidney deterioration and renal failure.
Signs and symptoms of chronic renal failure are initially insidious and include
progressive features such as: • Loss of appetite and nausea • Fatigue and weakness
Kidney (Renal) Failure There are two kidneys of which the principal role is the elimination of waste material and the regulation of the volume and composition of body fluid. They provide, in fact an active filtration system, filtering out from the blood a variety of molecular components and selectively reabsorbing the elements of the filtrate which must be kept.
• Poor sleep • Mental dulling • Swollen feet and ankles • Muscle twitching • Sleep problems • Itching • Breathlessness • Raised blood pressure which is
difficult to control
These days there is a much greater awareness of renal function and eGFR now enables early signs of renal failure to be detected.
Chronic Kidney Disease (CKD) may be classified by eGFR in ml/min
• 90+ normal or high • 60-89 mild reduction related to
normal range for young adult • 45-59 mild to moderate reduction • 30-44 moderate to severe reduction • 15-29 severe reduction • <15 end stage renal failure
The lower the number, the more severe the renal disease.
CKD is caused by a number of diseases
• High blood pressure (hypertension). Raised blood pressure over time gradually damages the small blood vessels in the kidneys
• Diabetes, particularly poorly controlled. Too mmuh glucose in the blood can damage the filtration mechanism
• Raised cholesterol builds up fatty deposits in the arteries supplying the kidneys and resulting in blockages and loss of function
• Kidney infections damage the kidney in general, particularly if not effectively treated
• Gloerulonephritis is kidney inflammation which damages the nephrons
• Polycystic Ovarian Disease is an inherited condition where, as the name suggests, mutliple cysts may distort, damage and destroy kidney tissue
• Blockage of urine passage, e.g. by kidney stones or an enlarged prostate
• Some medications may damage the kidney especially when used long-term
Treatment of CKD Even with all the miracles of modern medicine, there is no cure for CKD.
Treatment is aimed at diagnosis of any factors which may contribute to deterioration of renal function and its effective elimination or management. Treatment will depend on the severity of the disease.
As you have seen me write so many times before in respect of so many different diseases, the first rule of treatment is to control any problem that makes the deterioration worse. Therefore
1. Control raised blood pressure 2. Control diabetes as effectively as
possible 3. Lower blood cholesterol 4. Treat any kidney diseases that are
amenable to treatment 5. Treat any factor affecting urine
outflow 6. Stop any medication likely to further
damage the kidney
At the same time it is important to review lifestyle to enable the sufferer to remain as healthy as possible.
If the kidney disease is very severe such that the function has been largely or virtually destroyed, treatment may be increased to include
1. Dialysis – This is a system of filtering blood. There are a variety of different systems which replicate some of the blood cleansing functions of the kidney and support the patient for months or years.
2. Renal transplant. This involves the transplantation of a healthy kidney into a patient with little or no kidney function. As long as the patient is fit enough to withstand the surgery and
a suitable donor can be found, anyone can have a transplant. The kidney may be taken from a close living relative or it may be a cadaveric (deceased) donation. About 3,000 such procedures are done a year. About three quarters of patients who undergo renal transplant survive for ten years or more.
Acute renal failure This is an abrupt deterioration in kidney function over a short period (days or weeks). The result is a severe or catastrophic reduction in the body’s ability to filter waste products or to control fluid balance and toxic products accumulate in the body.
The principal waste product is urea and the resulting condition is called uraemia. Urine output declines often to little or nothing.
Causes There are a variety of reasons why the kidneys may fail
• Acute tubular necrosis. This is a complex term which means that the filter units deteriorate and die. It is commonly caused by low blood pressure or some sort of agent which is poisonous to the kidney.
• Sudden, severe dehydration • Some auto-immune diseases
affecting the kidneys. These are diseases where the body mistakes itself as ‘foreign’ and attacks itself. They include nephrotic syndrome and nephritis.
• Complication of surgical operations • Poisons or medication • Urinary tract obstruction
Course and Outcome The course of the condition is variable and depends on how severe the damage to the kidney is.
With appropriate treatment (medical support and treatment of the cause) recovery is normally within 7-21 days but may be prolonged in situations such as
sepsis. However there is still a significant mortality.
Modern intensive care improvements are gradually improving the survival and recovery rates.
The kidney is an amazing organ, so often taken for granted but vital for the body’s continuing function and homeostasis… maintenance of stable operation of all the bodily functions.
