Fluids and Electrolyte Balance

Flashcards covering fluid and electrolyte balance, including distribution, transport mechanisms, regulation, and related concepts.

What is total body water (TBW)?

Makes up approximately 70% of adult body weight and is divided into intracellular and extracellular fluid.

What is intracellular fluid (ICF)?

This is the fluid inside cells, making up about two-thirds of total body water.

What is extracellular fluid (ECF)?

This is the fluid outside cells, including plasma (in blood vessels) and interstitial fluid (between cells), making up about one-third of total body water.

What is passive transport?

Movement of substances across the membrane without using energy, moving from high to low concentration.

What is diffusion?

It involves the movement of gas, liquids, and solutions from high to low concentration.

What is facilitated diffusion?

This type of diffusion needs carrier molecules to transport large molecules like glucose across the membrane.

What is osmosis?

Water moves from low solute to high solute concentration across a semipermeable membrane to dilute the concentrated solution until equilibrium is achieved.

What is active transport?

Movement from low to high concentration that requires energy (ATP) to move substances against the concentration gradient.

What does ATP stand for?

Adenosine Triphosphate; it’s a small molecule that stores and transfers energy in cells.

What is the sodium-potassium pump (Na+/K+ pump)?

Constant movement of potassium (K+) in and sodium (Na+) out to maintain homeostasis.

What is fluid balance?

Occurs when water is in the correct proportions in fluid compartments, with fluid intake equaling fluid output in 24 hours.

What is the average daily fluid intake?

Approximately 2500 ml of water obtained from eating, drinking, and metabolic processes.

What are the primary routes of fluid loss?

Urine, faeces, perspiration, and exhaled air.

What regulates thirst?

Thirst center in the brain that helps maintain homeostasis.

Which patients are at risk of fluid and electrolyte imbalances?

Postoperative patients, those with severe trauma or burns, chronic diseases (CHF, diabetes, cancer), NPO patients, those receiving IVIs or diuretics, and the elderly.

What are the types of body secretions?

Blood, saliva/mucus, tears, gastric content, urination, stool, perspiration, and evaporation.

What is the composition and function of blood?

RBCs, WBCs, platelets, plasma (water, proteins, nutrients, hormones); it transports oxygen, nutrients, waste, and immune cells.

What is the composition and function of saliva/mucus?

Water, enzymes, electrolytes, mucins; it provides lubrication, digestion, and protection.

What is the composition and function of tears?

Water, salt, lysozyme, antibodies; it lubricates eyes, flushes out debris, and has antimicrobial properties.

What is the average urine output?

Average urine output for adults is 1500 ml

What counts as intake?

Oral fluids, ice blocks, foods liquid at room temperature, IV fluids, and tube feedings.

What counts as output?

Urine, blood loss, drainage from wounds/tubes, sweating, emesis, and bowel movement.

Converting Common Measurements

1 Tbs = 15 ml. 2 Tbs = 30 ml. 1 cup = 250 ml. 1 L= 1000 ml

What is dehydration?

Occurs when output exceeds intake due to excessive perspiration, poor fluid intake, diarrhea, vomiting, bleeding, burns, etc.

What happens when TBW output exceeds intake?

Kidneys retain fluid and the urine output decreases to compensate.

Definition: output exceeds intake

excessive perspiration, poor fluid intake, diarrhoea, vomiting, bleeding, pneumonia, pyrexia, insufficient intake, exhaustion, burns, Elderly people, draining tubes, Post-op patients, Restricted intake e.g. kidney failure

Symptoms of edema

High salt intake, infections, injuries or burns, certain kidney diseases, certain heart diseases or heart inefficiencies, Sitting too long in one position, Infiltration of an IV

Urine PH

normal 6 or between 4.6-8

Specific gravity

1005-1030

Clear liquid diet foods

Tea, water, coffee, clear broths, ginger ale, juice, gelatin

Full liquid diet

Ice cream, vegetable juice, cream, butter, smooth peanut butter, yogurt

Soft diet

Scrambled eggs, mashed potatoes, banana, cooked oatmeal, desserts