Urine output Health Dictionary

The volume of blood pumped out per minute by the ventricles of the heart. It is one measure of the heart’s e?ciency. At rest, the heart of a healthy adult will pump between 2.5 and 4.5 litres of blood every minute. Exercise will raise this to as much as 30 litres a minute but, if this ?gure is low, it suggests that the heart muscle may be diseased or that the person has suffered severe blood loss.... cardiac output

Waste substances resulting from the body’s metabolic processes, selected by the KIDNEYS from the blood, dissolved in water, and excreted. Urine is around 96 per cent water, the chief waste substances being UREA (approximately 25 g/1), common salt (approximately 9 g/l), and phosphates and sulphates of potassium, sodium, calcium, and magnesium. There are also small amounts of URIC ACID, ammonia, creatinine, and various pigments. Poisons, such as MORPHINE, may be excreted in the urine; and in many infections, such as typhoid fever (see ENTERIC FEVER), the causative organism may be excreted.

The daily urine output varies, but averages around 1,500 ml in adults, less in children. The ?uid intake and ?uid output (urine and PERSPIRATION) are interdependent, so as to maintain a relatively constant ?uid balance. Urine output is increased in certain diseases, notably DIABETES MELLITUS; it is diminished (or even temporarily stopped) in acute glomerulonephritis (see under KIDNEYS, DISEASES OF), heart failure, and fevers generally. Failure of the kidneys to secrete any urine is known as anuria, while stoppage due to obstruction of the ureters (see URETER) by stones, or of the URETHRA by a stricture, despite normal urinary secretion, is known as urinary retention.

Normal urine is described as straw- to amber-coloured, but may be changed by various diseases or drugs. Chronic glomerulonephritis or poorly controlled diabetes may lead to a watery appearance, as may drinking large amounts of water. Consumption of beetroot or rhubarb may lead to an orange or red colour, while passage of blood in the urine (haematuria) results in a pink or bright red appearance, or a smoky tint if just small amounts are passed. A greenish urine is usually due to BILE, or may be produced by taking QUININE.

Healthy urine has a faint aroma, but gives o? an unpleasant ammoniacal smell when it begins to decompose, as may occur in urinary infections. Many foods and additives give urine a distinctive odour; garlic is particularly characteristic. The density or speci?c gravity of urine varies normally from 1,015 to 1,025: a low value suggests chronic glomerulonephritis, while a high value may occur in uncontrolled diabetes or during fevers. Urine is normally acidic, which has an important antiseptic action; it may at times become alkaline, however, and in vegetarians, owing to the large dietary consumption of alkaline salts, it is permanently alkaline.

Chemical or microscopical examination of the urine is necessary to reveal abnormal drugs, poisons, or micro-organisms. There are six substances which must be easily detectable for diagnostic purposes: these are ALBUMINS, blood, GLUCOSE, bile, ACETONE, and PUS and tube-casts (casts from the lining of the tubules in the kidneys). Easily used strip tests are available for all of these, except the last.

Excess of urine It is important to distinguish urinary frequency from increase in the total amount of urine passed. Frequency may be due to reduced bladder capacity, such as may be caused by an enlarged PROSTATE GLAND, or due to any irritation or infection of the kidneys or bladder, such as CYSTITIS or the formation of a stone. Increased total urinary output, on the other hand, is often a diagnostic feature of diabetes mellitus. Involuntary passage of urine at night may result, leading to bed wetting, or NOCTURNAL ENURESIS in children. Diagnosis of either condition, therefore, means that the urine should be tested for glucose, albumin, gravel (fragments of urinary calculi), and pus, with appropriate treatment.... urine

See URINE RETENTION.... retention of urine

Severe burning sensation during micturition... scalding of urine

This occurs when URINE is produced by the kidneys but not voided by the bladder. It is generally less serious than ANURIA, in which urine is not produced.

Causes Neurological injury, such as trauma to the spinal cord, may cause bladder weakness, leading to retention, although this is rare. Obstruction to out?ow is more common: this may be acute and temporary, for example after childbirth or following surgery for piles (HAEMORRHOIDS); or chronic, for example, with prostatic enlargement (see PROSTATE GLAND). Commonly seen in elderly men, this leads to reduced bladder capacity, with partial emptying every few hours. Total retention is rare, but may result from a stricture, or narrowing, of the URETHRA (see also URETHRA, DISEASES OF AND INJURY TO) – usually the result of infection or injury – or to pressure from a large neighbouring tumour.

Retention is generally treated by regular use of a urethral catether (see CATHETERS), various types of which are available. Tapping of the bladder with a needle passed above the pubis is rarely necessary, but may occasionally be required in cases of severe stricture.... urine retention

See urinalysis.... urine tests

(aminoacidopathy) an inborn defect of amino acid metabolism causing an excess of valine, leucine, isoleucine, and alloisoleucine in the urine, which has an odour like maple syrup. Treatment is dietary; if untreated, the condition leads to learning disabilities and death in infancy.... maple syrup urine disease

(MSU) a specimen of urine that is subjected to examination for the presence of microorganisms. In order to obtain a specimen that is free of contamination, the periurethral area is cleansed and the patient is requested to discard the initial flow of urine before collecting the specimen in a sterile container.... midstream specimen of urine

Bladder instability. Urine is usually passed 4 to 6 times daily; anything in excess of this is known as ‘frequency’. In the elderly it may be due to weak bladder muscles and sphincter, or to unrecognised overflow due to prostatic obstruction.

Causes may also be psychological: worry, excitement, emotional crises such as school exams. Where the trouble is persistent attention should be focussed on the bladder (cystitis), inflammation of the kidneys, even the presence of stone.

Simple frequency may arise from cold weather, nervous excitement, or early pregnancy. Other predisposing factors are: diabetes mellitis, enlarged prostate gland, stone in the kidney or bladder. Alternatives. Teas. American Cranesbill, Agrimony, Cornsilk, Horsetail, Passion flower, Plantain, Skullcap, Uva Ursi, Huang Qi (Chinese). Saw Palmetto (prostate gland).

Tablets/capsules. Cranesbill (American), Gentian, Liquorice.

Powders. Equal parts: Cranesbill, Horsetail, Liquorice. Mix. Dose: 500mg (two 00 capsules or one-third teaspoon). Thrice daily.

Tinctures. Equal parts: Cramp bark and Horsetail. Dose: 30-60 drops, thrice daily.

Practitioner. Tinctures. Alternatives:–

Formula 1. Ephedra 30ml; Geranium 20ml; Rhus aromatica 20ml; Thuja 1ml. Aqua to 100ml. Sig: 5ml (3i) tds aq cal pc.

Formula 2. Equal parts: Ephedra and Horsetail. 15-60 drops thrice daily; last dose bedtime.

A. Barker FNIMH. Dec Jam Sarsae Co Conc BPC 1 fl oz (30ml) . . . Liquid extract Rhus 240 minims (16ml) . . . Liquid extract Passiflora 60 minims (4ml) . . . Syr Althaea 2 fl oz (60ml) . . . Aqua to 8oz (240ml). Dose: 2 teaspoons thrice daily; last dose bedtime.

Tincture Arnica. German traditional. 1 drop in honey at bedtime.

Pelvic exercises. Alternate hot and cold Sitz baths. Swimming, Cycling.

Address. Incontinence Advisory Service, Disabled Living Foundation, 380-384 Harrow Road, London W9 2HU. ... frequency of urine

Urine may be produced in abnormal amounts or have an abnormal appearance or composition.

Conditions of abnormal production of urine include excessive production (see urination, excessive), oliguria, and anuria. Abnormal appearances of urine include cloudiness (which may be caused by a urinary tract infection, a calculus, or the presence of salts); haematuria; discoloration from certain foods or drugs; and frothiness (which may be caused by an excess of protein).Abnormal composition of the urine may occur in diabetes mellitus, kidney failure, and sometimes glomerulonephritis and nephrotic syndrome, as well as in other kidney disorders such as Fanconi’s syndrome and renal tubular acidosis.... urine, abnormal