An obligatory urine loss occurs because of the need to remove various solutes from the body. ... The minimal amount of fluid loss from the body that can occur is referred to as the obligatory water loss. This sets a figure for the minimal amount of fluid intake that is required to maintain total water balance.

What is obligatory water excretion?

The obligatory water loss refers to the lowest volume of urine that must be produced to eliminate solutes.

What is obligatory water output?

Obligatory fluid output is the minimum output of urine necessary to remove wastes and is estimated to be roughly 700 mL per day or 30 mL per hour.

What is the obligatory water loss per day?

o·blig·a·to·ry wa·ter loss

Minimal volume of urine that must be produced to dispose of dissolved wastes, which amounts to about 600 mOsm/day. Individuals who cannot concentrate urine must produce a larger volume to excrete the daily metabolic load, subjecting them to greater obligatory water loss.

What is obligatory urine volume?

Obligatory urine volume (OUV) is the water volume necessary to excrete all urine solutes. To calculate OUV, a threshold of maximum urine osmolality of 830 mOsm/kg is used for a 20 years old individual [21].

Renal System - Physiology - Part 4 - (Ureters, Bladder, Urethra, Obligatory Water Loss)

42 related questions found

What is the difference between obligatory and facultative water loss?

Water reabsorption together with solutes in tubular fluid is called obligatory water reabsorption. Reabsorption of the final water, facultative reabsorption, is based on need and occurs in the collecting ducts and is regulated by ADH.

Why is fluid restriction in renal failure?

When you are on dialysis, your kidneys are no longer able to keep the right balance of fluid in your body. They cannot remove enough. That's why it's so important to limit how much sodium (salt) and fluid you have between dialysis treatments.

What factors influence a person's water requirement?

Factors that influence water needs

• Exercise. If you do any activity that makes you sweat, you need to drink extra water to cover the fluid loss. ...
• Environment. Hot or humid weather can make you sweat and requires additional fluid intake. ...
• Overall health. ...
• Pregnancy or breast-feeding.

Which factors are involved in regulation of water metabolism?

Balance is controlled by thirst, access to water, solute intake, antidiuretic hormone, cortisol, aldosterone, natriuretic peptides, renal receptors for hormone action, renal water channels called aquaporins, level of kidney function, and drugs.

Why fluid balance is important?

Maintenance of an adequate fluid balance is vital to health. Inadequate fluid intake or excessive fluid loss can lead to dehydration, which in turn can affect cardiac and renal function and electrolyte management. Inadequate urine production can lead to volume overload, renal failure and electrolyte toxicity.

What is the daily obligatory urine volume required for excretion wastes from the body?

A daily output of 400 to 500 ml of urine is required to excrete obligatory nitrogenous wastes. In adults an inadequate urine output (oliguria) is often defined as <0.5 ml/kg/hr.

How do you calculate obligatory urine volume?

Thus, the obligatory urine volume obtained by dividing the daily osmolar excretion (mOsm/day) by the maximum urine osmolality (mOsm/kg H2O), is approximately 500ml of urine in its highest concentration.

What is abnormal fluid loss?

The body may lose too much fluid due to diarrhea, vomiting, severe blood loss, or high fever. Lack of a hormone called antidiuretic hormone (ADH) can cause the kidneys to get rid of too much fluid. This results in extreme thirst and dehydration.

What is the major hormone that regulates water loss?

The body's homeostatic control mechanisms ensure that a balance between fluid gain and fluid loss is maintained. The hormones ADH (antidiuretic hormone, also known as vasopressin ) and aldosterone play a major role in this.

What are three conditions that would increase a persons water needs?

What about the advice to drink 8 glasses a day?

• Exercise. If you do any activity that makes you sweat, you need to drink extra water to cover the fluid loss. ...
• Environment. Hot or humid weather can make you sweat and requires additional fluid. ...
• Overall health. ...
• Pregnancy and breast-feeding.

What factors decrease our fluid output?

Environmental temperature and humidity, altitude, volume of air inspired, air currents, clothing, blood circulation through skin, and water content of the body can all affect insensible water loss (15).

Why is water important for metabolic reactions?

Water is an essential part of most metabolic processes within organisms. ... In catabolic reactions, water is used to break bonds in larger molecules in order to make smaller molecules. Water is central to two related, fundamental metabolic reactions in organisms: photosynthesis and cellular respiration.

How does the body regulate fluid and electrolyte including ph balance?

One lies... read more by filtering electrolytes and water from blood, returning some to the blood, and excreting any excess into the urine. Thus, the kidneys help maintain a balance between daily consumption and excretion of electrolytes and water.

Can water be metabolized?

The body obtains water primarily by absorbing it from the digestive tract. Additionally, a small amount of water is produced when the body processes (metabolizes) certain nutrients. The body loses water primarily by excreting it in urine from the kidneys.

Does requirement of water vary?

Given the extreme variability in water needs which are not solely based on differences in metabolism, but also in environmental conditions and activity, there is not a single level of water intake that would ensure adequate hydration and optimal health for half of all apparently healthy persons in all environmental ...

Which disease factor increases fluid requirements?

Other conditions such as bladder infections, urinary tract stones, gout and constipation may also require increased water or fluid intake.

What increases fluid needs?

Most of your fluid needs are met through the water and beverages you drink. However, you can get some fluids through the foods that you eat as well. For example, broth soups and foods with high water content – such as celery, tomatoes, or melons – can contribute to fluid intake. Carry a water bottle with you.

How does kidney failure affect water balance?

With kidney failure, your kidneys can't get rid of extra water. Taking in too much water can cause swelling, raise your blood pressure, and make your heart work harder.

How can we control water intake?

6 Simple Ways to Reduce Water Retention

1. Eat Less Salt. Salt is made of sodium and chloride. ...
2. Increase Your Magnesium Intake. Magnesium is a very important mineral. ...
3. Increase Vitamin B6 Intake. Vitamin B6 is a group of several related vitamins. ...
4. Eat More Potassium-Rich Foods. ...
5. Try Taking Dandelion. ...
6. Avoid Refined Carbs.

Is fluid restriction needed in heart failure?

Conclusion: Fluid restriction should not be recommended to all heart failure patients. However, temporary fluid restriction can be considered in decompensated heart failure and/or patients with hyponatremia. Tailored fluid restriction based on body weight (30 ml/kg per day) seems to be most reasonable.