Fluid and Electrolyte Balance Review

Flashcards covering fluid compartments, movement mechanisms (osmosis, diffusion, active transport), dehydration, hypovolemia, hypervolemia, IV therapy types, and major electrolyte imbalances (Na, K, Ca, Mg, PO4).

What is the definition of Homeostasis in the context of fluids and electrolytes?

A process where various physiological mechanisms within the body respond to internal changes to maintain relative constancy in the internal environment.

According to the lecture, what are the total body water percentages for males, women, and babies?

Males: $60\%$, women: about $54\%$, and babies/young children: about $70\%$.

Which fluid compartment contains $2/3$ of the total body water?

Intracellular fluid (ICF).

What are the three components that make up the Extracellular fluid (ECF)?

Intravascular fluid (plasma), Interstitial fluid, and Transcellular fluid.

Define 'Third Spacing' as described in the transcript.

The abnormal shift of fluid into areas where the body cannot use it, such as ascites or pericardial effusion.

How does Osmosis differ from Diffusion?

Osmosis is the movement of water from an area of lesser to greater solute concentration, while Diffusion is the passive movement of particles from higher to lower concentration.

What is required for Active Transport to move ions against osmotic pressure?

Energy from $ATP$.

Which part of the brain regulates the thirst mechanism and what stimulates it?

The hypothalamus; it is stimulated by an increase in extracellular fluid osmolality and drying of the mucous membrane.

What is the goal of the Renin-Angiotensin-Aldosterone System (RAAS)?

To manage blood pressure by stimulating sodium and water retention to increase blood volume.

Distinguish between Sensible and Insensible fluid loss.

Sensible loss is measurable (e.g., urine, emesis, wound drainage), while Insensible loss cannot be measured or seen (e.g., perspiration, respiration, exhaled air).

What is the specific definition of Dehydration provided in the notes?

Excess water loss without a loss of sodium.

What level of urinary output is considered oliguria?

$<30\,ml/hr$.

What is the formula for Cardiac Output (CO) and what is the normal resting range?

$CO = \text{Stroke Volume} \times \text{HR}$; the normal range is $4-6\,L/min$.

What criteria define Orthostatic Hypotension?

A drop in Systolic Blood Pressure (SBP) $\ge 20\,mmHg$ or a drop in Diastolic Blood Pressure (DBP) $\ge 10\,mmHg$ when standing.

How does Hypovolemia differ from Dehydration?

Hypovolemia is caused by a loss of both water and electrolytes, leading to decreased circulating blood volume.

What are the common laboratory findings in a client with Dehydration or Hypovolemia?

Increased $BUN$, increased Creatinine ($CR$), increased Hematocrit ($Hct$) and Hemoglobin ($Hgb$), and increased Urine Specific Gravity ($SG$).

What is the difference between Crystalloids and Colloids in IV therapy?

Crystalloids contain small molecules that pass through cell membranes; Colloids contain large molecules that do not pass through membranes and pull fluid into the bloodstream.

Which isotonic IV solution is the only one used with blood product administration?

$0.9\%$ Sodium Chloride ($NaCl$), also known as Normal Saline ($NS$).

What is the purpose of administering a Hypotonic solution like $0.45\%$ Sodium Chloride?

To make the 'cell swell' by moving water from the extracellular space into the cells.

What are the clinical manifestations of Hypervolemia (Fluid Volume Excess)?

Acute weight gain, peripheral edema, ascites, distended jugular veins (JVD), crackles in the lungs, shortness of breath, and a bounding pulse.

What are the characteristics of 3+ Pitting Edema?

A deep pit ($6\,mm$) that remains for several seconds after pressing, with obvious skin swelling.

In fluid management, how much fluid volume is equivalent to $1\,kg$ ($2.2\,lb$) of body weight?

$1\,liter$ of fluid.

How are ice chips measured for fluid intake?

Ice chips are measured as half of their frozen volume (e.g., $8\,oz$ of ice chips equals $4\,oz$ of intake).

What is the normal serum range for Sodium ($Na^+$)?

$136-145\,mEq/L$.

What neurological symptoms can result from Hyponatremia?

Headache, restlessness, confusion, irritability, lethargy, seizures, and coma.

What is the normal serum range for Potassium ($K^+$)?

$3.5-5.0\,mEq/L$.

What is a critical safety rule for IV Potassium administration?

It must always be diluted and administered slowly ($5$ to $10\,mEq/hr$); never give it via IV push due to the high risk of cardiac arrest.

What are Chvostek's sign and Trousseau's sign indicative of?

Hypocalcemia ($Ca^+$ deficiency) and potential neuromuscular irritability.

What is the normal serum range for Magnesium ($Mg^+$)?

$1.3-2.1\,mEq/L$.

What are the primary roles of Phosphorus in the body?

$ATP$ production, bone and teeth formation, cell membrane structure, oxygen delivery, and acid-base buffering.

What is the normal pH range of blood and which organs help maintain it?

The normal range is $7.35-7.45$; the kidneys and lungs help maintain this balance.