NURS 3372 FINAL EXAM BLUEPRINT- SPRING 2024
1) Blood components and body fluids- values, compartments
Blood Components
Blood is a complex fluid with several key components:
• Plasma: The liquid portion of blood, making up about 55% of its volume. It contains water,
electrolytes, proteins (like albumin, globulins, and fibrinogen), hormones, nutrients, and
waste products.
• Red Blood Cells (RBCs): Also called erythrocytes, these cells carry oxygen from the lungs to
the body's tissues and return carbon dioxide to the lungs. RBCs make up about 40-45% of
blood volume.
• White Blood Cells (WBCs): Also known as leukocytes, they are part of the immune system.
They include neutrophils, lymphocytes, monocytes, eosinophils, and basophils. WBCs make up
about 1% of blood volume.
• Platelets: Also called thrombocytes, they are involved in blood clotting and make up less
than 1% of blood volume.
Normal Values for Blood Components
• RBC count:
• Males: 4.7–6.1 million cells per microliter
• Females: 4.2–5.4 million cells per microliter
• WBC count: 4,500–11,000 cells per microliter
• Platelet count: 150,000–450,000 per microliter
• Hematocrit: The percentage of RBCs in blood.
• Males: 40.7–50.3%
• Females: 36.1–44.3%
• Hemoglobin: The oxygen-carrying protein in RBCs.
• Males: 13.8–17.2 g/dL
• Females: 12.1–15.1 g/dL
Body Fluid Compartments
The human body contains various fluid compartments:
• Intracellular Fluid (ICF): Fluid within cells, comprising about 40% of total body weight.
, • Extracellular Fluid (ECF): Fluid outside cells, accounting for about 20% of total body weight. It
is further divided into:
• Interstitial Fluid (ISF): Fluid between cells, about 75% of ECF.
• Plasma: The liquid component of blood, about 20% of ECF.
• Transcellular Fluid: Specialized fluids in compartments like cerebrospinal fluid,
synovial fluid, and others, accounting for about 5% of ECF.
Normal Values for Body Fluids
• Total Body Water (TBW): About 60% of total body weight in males, 50–55% in females.
• Intracellular Fluid (ICF): About 25–28 liters.
• Extracellular Fluid (ECF): About 14–17 liters.
• Plasma: About 3–3.5 liters.
• Interstitial Fluid (ISF): About 10–11 liters.
• Transcellular Fluid: A few hundred milliliters to 1 liter.
2) Starling forces, movement of fluids between compartments, under what conditions it moves in
a particular direction.
Starling forces, also known as Starling's Law of Capillarity, describe the forces that control the
movement of fluid into and out of capillaries. There are four key forces at play:
1. Capillary Hydrostatic Pressure (Pc): This is the pressure exerted by blood within the capillaries.
It tends to push fluid out of the capillaries into the interstitial space. This pressure is higher at
the arterial end of the capillary and lower at the venous end.
2. Interstitial Hydrostatic Pressure (Pi): This is the pressure in the interstitial fluid surrounding the
capillaries. It tends to push fluid back into the capillaries. Normally, this pressure is relatively
low.
3. Capillary Oncotic (Colloid Osmotic) Pressure (πc): This pressure is created by plasma
proteins (like albumin) within the capillaries, which tend to pull fluid back into the capillaries
from the interstitial space.
4. Interstitial Oncotic Pressure (πi): This pressure is due to proteins in the interstitial fluid,
which tends to pull fluid out of the capillaries.
Increased Capillary Hydrostatic Pressure: Conditions like hypertension or venous congestion can increase
this pressure, leading to increased filtration and potential edema (fluid accumulation in tissues).
Decreased Capillary Oncotic Pressure: A reduction in plasma proteins (e.g., due to malnutrition, liver
disease, or kidney disease) reduces the pulling force into the capillaries, leading to increased filtration
and edema.
,Increased Interstitial Oncotic Pressure: Increased proteins in the interstitial space (due to inflammation
or tissue damage) can also lead to increased filtration.
Decreased Interstitial Hydrostatic Pressure: This can enhance fluid movement out of the capillaries.
3) Electrolytes (Na, K, Ca, Mg, PO4)- organ systems affected, values, conditions, and the
relation between water balance and electrolytes.
Sodium (Na)
• Normal Values: 135–145 mEq/L
• Organ Systems Affected: Mainly the nervous system and muscles.
• Role: Sodium is critical for maintaining fluid balance and regulating blood pressure. It also plays
a role in nerve transmission and muscle function.
• Conditions:
• Hyponatremia: Low sodium, often due to excess water intake, certain medications,
or conditions like SIADH (Syndrome of Inappropriate Antidiuretic Hormone
Secretion). Symptoms include headache, confusion, seizures, and muscle cramps.
• Hypernatremia: High sodium, typically from dehydration or excess sodium intake. It
can lead to thirst, dry mouth, confusion, seizures, and coma.
Potassium (K)
• Normal Values: 3.5–5.0 mEq/L
• Organ Systems Affected: Cardiac and muscular systems.
• Role: Potassium is crucial for cardiac muscle contraction and nerve function.
• Conditions:
• Hypokalemia: Low potassium, often due to diuretics, vomiting, or diarrhea. It can
cause muscle weakness, cardiac arrhythmias, and paralysis.
• Hyperkalemia: High potassium, possibly from kidney failure or certain medications.
It can lead to muscle weakness, cardiac arrhythmias, and cardiac arrest.
Calcium (Ca)
• Normal Values: 8.5–10.5 mg/dL (total calcium)
• Organ Systems Affected: Skeletal, cardiac, and nervous systems.
• Role: Calcium is vital for bone health, muscle contraction, and neurotransmitter release.
• Conditions:
, • Hypocalcemia: Low calcium, often due to hypoparathyroidism or vitamin D
deficiency. Symptoms include muscle cramps, tetany, and cardiac arrhythmias.
• Hypercalcemia: High calcium, potentially from hyperparathyroidism or cancer. It
can lead to kidney stones, bone pain, and confusion.
Magnesium (Mg)
• Normal Values: 1.7–2.2 mg/dL
• Organ Systems Affected: Muscular and cardiac systems.
• Role: Magnesium is involved in over 300 enzymatic reactions and contributes to muscle
and nerve function.
• Conditions:
• Hypomagnesemia: Low magnesium, often due to alcoholism, malnutrition, or
diuretics. It can cause muscle weakness, tetany, and cardiac arrhythmias.
• Hypermagnesemia: High magnesium, possibly from kidney failure or excessive
supplementation. It can lead to muscle weakness, decreased reflexes, and
respiratory depression.
Phosphate (PO4)
• Normal Values: 2.5–4.5 mg/dL
• Organ Systems Affected: Skeletal, muscular, and cardiac systems.
• Role: Phosphate is important for bone health, energy storage (as ATP), and cellular signaling.
• Conditions:
• Hypophosphatemia: Low phosphate, often due to malnutrition or
hyperparathyroidism. It can cause muscle weakness, respiratory failure, and seizures.
• Hyperphosphatemia: High phosphate, possibly from kidney disease or
hypoparathyroidism. It can lead to calcification of tissues and bone
pain.
Relation Between Water Balance and Electrolytes
Water balance and electrolytes are closely linked. Here's how:
• Water Regulation: Sodium is the key driver of water balance. The body uses sodium levels to
regulate water volume and distribution. When sodium levels are high, the body retains
water, leading to increased blood volume and blood pressure. When sodium levels are low,
the body loses water.
• Osmotic Pressure: Sodium is the primary determinant of extracellular osmotic pressure. It
affects the movement of water between compartments, such as between the blood and
interstitial fluid. Imbalances in sodium can lead to fluid shifts that cause edema or
dehydration.
