Daily amount of urine in adults and children: how to determine what it depends on and why it changes

What is diuresis? This term is used to determine the amount of urine excreted over a specified period of time. In medicine, it is customary to measure the volume of urine released in 24 hours. An adult should produce 1 to 2 liters of urine per day. Pathological processes in the human body can significantly affect diuresis.

What is daily diuresis

Daily diuresis in adults and children is the volume of urine excreted per day. This indicator reflects the functioning of the kidneys and provides indirect information about the condition of the heart, liver, and endocrine system. The rates of fluctuations in diuresis in adults depend on:

• amount of liquid drunk;
• nature of nutrition;
• ambient temperature.

The definition of urinary output also includes the number of urinations during the day and at night. When examining urine, its density is determined, which indicates the capacity of the kidneys. A type of study is the Zimnitsky analysis, hourly diuresis.

Why does a doctor need to know the patient's hourly urine output?

In severely ill patients who are unable to void on their own, hourly urine output is measured using a urinary catheter. The volume of urine excreted per hour allows you to monitor the patient’s condition in a coma. The normal amount of urine is 30-50 ml every hour. If this indicator is less than 15 ml, this may indicate that the intensity of infusions should be increased. If blood pressure is normal with a simultaneous decrease in diuresis, the doctor makes an intravenous injection of Salnikov's drug, which stimulates urination.

Based on the tests, the doctor receives certain information about the functioning of organs

Normal values ​​for daily diuresis are relative and vague, as they depend on a combination of various factors, including the patient’s drinking regimen, his weight, gender, age, diet and medications. Therefore, the daily urine rate in women and men can be approximately the same, regardless of gender.

Table of urinary excretion indicators for men and women

For daily diuresis, the norms fluctuate slightly. In adult men and women the rate is almost the same; in children it varies by age.

Hourly diuresis varies depending on physical activity and diet. Until 3-4 o'clock in the afternoon it is higher than in the evening.

Symptoms of increased daily diuresis

Diuresis normally ranges from 1 to 1.5 liters per day, depending on the characteristics of the body. An increase or change in it indicates ongoing pathological processes. There are the following types of disturbances in daily diuresis in adults:

• polyuria - the volume of urine excreted is more than two liters;
• oliguria - the volume of urine excreted is less than 500 ml;
• nocturia - most of the urine is released at night;
• anuria - a person excretes less than 50 ml of urine per day.

An increase in daily urination is accompanied by frequent urination and a large volume of urine per urination. Depending on the underlying disease, a person feels pain in the lumbar region, thirst, and dry mouth.

Oliguria is characterized by infrequent urination with a small amount of urine. Abdominal and back pain, swelling, nausea, and headaches are observed.

Anuria is a serious condition that is accompanied by the accumulation of toxins in the blood, leading to the development of coma.

Reasons for increased daily diuresis

Fluctuations in urinary output are not an independent disease. This is a symptom that is observed in diseases of the kidneys, liver, heart, diabetes and some infections.

Polyuria is observed with:

• reduction of edema;
• diabetes mellitus or diabetes insipidus;
• in the second period of hemorrhagic fever with renal syndrome.

Physiological polyuria is observed with excessive fluid intake and diuretic medications. For pregnant women, slight polyuria is normal.

Oliguria and anuria occur with blood loss, vomiting, acute kidney inflammation, and renal failure.

Daytime diuresis should prevail over nighttime. If there is an inverse ratio, this indicates kidney damage.

Why are diuresis rates increased?

An increase in the amount of urine excreted is called “polyuria,” which can be physiological or pathological. Physiological polyuria can be triggered by the patient’s increased drinking regimen or consumption of diuretic products (for example, watermelon). This condition is not a disease and does not require treatment, and the volume of urine excreted will return to normal on its own.

Pathological polyuria is provoked by such processes as:

• fever;
• swelling;
• diabetes;
• Conn's syndrome - excessive secretion of aldosterone;
• dilated renal pelvis due to impaired urine outflow (hydronephrosis);
• hyperparathyroidism (a disease of the endocrine system in which the secretion of parathyroid hormone increases);
• mental disorders;
• acute renal failure;
• taking certain groups of medications, such as glycosides and diuretics.

Quite often, “polyuria” occurs in patients with diabetes mellitus

Violation of the proportion of daytime and nighttime urine volume (nocturia) can also be a manifestation of a malfunction in the functioning of the urinary system. A condition in which nocturnal diuresis exceeds daytime diuresis, even with normal daily values, is considered pathological. Nocturia can be caused by genitourinary tract infections, hypertension, cardiac decompensation, or taking medications to reduce edema.

Indications for the study of daily diuresis

Determination of diuresis in adults is indicated if the following diseases are suspected:

• diabetes mellitus or diabetes insipidus;
• infections with kidney damage;
• glomerulonephritis;
• renal failure;
• heart failure;
• cirrhosis of the liver.

The main symptoms indicating a urinary disorder: weakness, increased fatigue, nausea, dry mouth, thirst, headaches. These are signs of fluid retention, intoxication of the body with metabolic products.

Urinary control is constantly carried out in people with decompensated diseases of the heart, liver and kidneys. Determination of hourly and daily diuresis is shown. In adults with chronic pathologies, daily diuresis does not return to normal on its own; it needs to be supported with medications, diet, and daily routine.

Contraindications

There may be days in a patient’s life when a urine test is not reliable:

• After sexual contact. In this case, there will be quite a lot of protein substances, but normally they should not be present when taking the test.
• Menstruation. During bleeding, no matter how hard a woman tries to cover her vagina, blood can get into the urine. And the restructuring of the body during this period affects the composition of urine.
• Alcohol and caffeine. These drinks are contraindicated before donating urine. If you consumed them the day before, the analysis should be postponed.
• Physical activity. During intense training, protein gets into the urine; as already mentioned, it shouldn’t be there.
• Stress. During times of stress, protein masses also enter the urine in large quantities.

Let us remind you once again how to store daily urine. Only in the cold! Some people think that urine, collected at one time and left for a day, will be the necessary material. But no, this is completely wrong! Pere

How is daily diuresis determined?

The rate of daily diuresis is determined by comparing the fluid drunk and excreted. ¾ of the liquid you drink is excreted. If an adult drinks 3 liters of water per day, then he should excrete 2 liters of urine. And this will not be a pathology. If an adult drank 3 liters, but excreted the same amount, more or less, this is already a deviation.

Urine analysis for daily diuresis

To collect urine, an adult will need a three-liter container. In the morning you should urinate in the toilet and collect all subsequent portions. All day you need to record the amount of fluid you drink, then compare this figure with the volume of urine excreted.

Another way to determine the norm of daily diuresis is a urine test according to Zimnitsky. Here, not only the total volume of urine of an adult is determined, but also the hourly volume of urine. During the day, urine is collected every three hours, and eight labeled jars are given for analysis. The collection begins at 6 a.m., the adult empties into the toilet. All subsequent portions are collected in containers according to the time indicated on them. If there was no urination for some period, the jar is left empty.

Determination of hourly urination is carried out in intensive care patients. This is an important indicator of kidney function. The development of anuria is an unfavorable prognostic sign.

Rules for collecting urine for research

A special feature of this type of examination is that all urine is collected within 24 hours, so it is not recommended to plan trips or other events on this day.

Simple rules on how to correctly collect daily urine for analysis:

1. The first thing you need to do is prepare a sterile, dried 2 or 3 liter container with a wide neck and a tight lid, or buy a specialized 2.7 liter plastic container from the pharmacy chain.
2. Record the start time of collecting material so that exactly 24 hours have passed. If you take urine for the first time at 7 am, then the last portion should be taken at 7 am the next day.
3. Wash your intimate organs without using products that contain added fragrances. It is possible to use a weak solution of potassium permanganate or furatsilin.
4. The initial portion of urine is not collected in the morning, after sleep, but the time is recorded.
5. You should urinate in a dry and clean small container and immediately pour the urine into the main container and close the lid tightly.
6. Store the container with all the urine on the bottom shelf of the refrigerator, away from freezing, and make sure that the lid is closed as tightly as possible.
7. On the day of the test, after the last urine collection in the morning, the entire contents of the main container should be carefully stirred and 150-200 grams should be poured into a special small vessel.

On a note! The rules for collecting daily urine for analysis for pregnant women are exactly the same as for everyone.

Before starting the study, you should find out from your doctor how much urine you need to take for analysis. Sometimes the doctor recommends bringing the entire large container to determine exactly how much fluid is released over a twenty-four hour period.

Interpretation of urine test results for daily diuresis

When determining the norm of diuresis, the following criteria are taken into account:

• the total volume of daily urine is 1-1.5 liters;
• the amount of urine excreted is ¾ of the liquid drunk;
• predominance of daytime urination over nighttime urination.

Increased amount of urine - polyuria. Decreased - oliguria or anuria. The predominance of nocturnal diuresis is nocturia.

Additionally, the density of urine is determined; it should be 1010-1012. If this number is higher, the urine density is low. If the number is lower, the urine density is high. This indicates a violation of the concentration function of the kidneys.

How to bring daily diuresis back to normal

The main way to restore urination is to treat the disease that caused the disturbance. For diabetes mellitus, this means constant use of insulin or other glucose-lowering drugs. Patients with diabetes should adhere to special diet No. 9. For diabetes insipidus, antidiuretic hormone is prescribed.

Infectious diseases accompanied by kidney damage are treated with antiviral agents or antibiotics. For glomerulonephritis, steroid and anti-inflammatory drugs are indicated. Liver cirrhosis is treated taking into account the pathology that caused it. If it is viral hepatitis, antiviral drugs are prescribed. Toxic cirrhosis is treated with hepatoprotectors and detoxification agents. Avoidance of alcohol is strictly required.

There is no need to restore physiological polyuria. It is associated with increased fluid consumption and normalizes on its own when returning to the usual drinking regimen.

How to prepare for the test

To significantly reduce the risk of receiving erroneous readings, it is important to prepare properly. The doctor tells you how to prepare during the consultation and when submitting a referral for analysis. 2-3 days before the delivery of the material, you must fulfill the basic requirements:

• maintain hygiene of the external genitalia during the period of collecting material;
• on the eve of the study, remove from the diet foods that contribute to urine coloring: beets, bright berries, carrots;
• limit the consumption of spicy, fatty, salty and very sweet foods;
• You should maintain your usual drinking regimen throughout the day;
• stop using chemicals.

In cases where taking medications is vital, you should not stop taking them. To correct the accuracy of the analysis indicators, you should inform the laboratory technician who will conduct the laboratory test about the list of medications and their dosage.

Diet No. 9

The main disease leading to polyuria is diabetes mellitus. Patients with this disease must follow a special diet. It is needed to normalize carbohydrate metabolism and reduce blood sugar. Basic principles of the diet:

• quickly digestible carbohydrates;
• animal fats;
• protein;
• exclusion of sugar, sweets;
• exclusion of broths;
• salt restriction.

Diet (table) No. 9
Dishes are steamed, boiled, stewed, baked. Sugar is replaced with xylitol or sorbitol. Lean fish, seafood, cottage cheese, vegetables and fruits should prevail. Baked goods, bread - made from bran, wholemeal flour. Daily diuresis is an important study that provides information about the condition of the kidneys, liver, and heart. It is used to identify diseases, as well as to control chronic pathologies.