Chapter 10: Fluid and Electrolytes

The text delineates the distribution of body fluids into intracellular and extracellular compartments, further dividing the latter into intravascular, interstitial, and transcellular spaces, while explaining the transport mechanisms of osmosis, diffusion, filtration, and active transport that govern fluid movement. It explores the crucial regulatory roles of the kidneys, lungs, heart, and endocrine system, specifically focusing on the Renin-Angiotensin-Aldosterone System (RAAS) and Antidiuretic Hormone (ADH) in controlling fluid volume and osmolality. The content thoroughly contrasts Fluid Volume Deficit (hypovolemia), characterized by weight loss and oliguria, with Fluid Volume Excess (hypervolemia), manifested by edema and distended jugular veins, offering specific nursing interventions for each. A significant portion of the chapter analyzes electrolyte imbalances, detailing the clinical manifestations and management for sodium disorders like hyponatremia and hypernatremia, which primarily affect the central nervous system, and potassium imbalances such as hypokalemia and hyperkalemia, which pose severe cardiac risks including arrhythmias and arrest. It further categorizes calcium imbalances, noting the risk of tetany and positive Chvostek and Trousseau signs in hypocalcemia, alongside magnesium, phosphorus, and chloride disturbances. The chapter also provides a deep dive into acid-base balance, explaining the bicarbonate-carbonic acid buffer system and differentiating between metabolic and respiratory acidosis and alkalosis based on arterial blood gas (ABG) analysis, pH levels, PaCO2, and bicarbonate values. Finally, the text covers parenteral fluid therapy, distinguishing between isotonic, hypotonic, and hypertonic intravenous solutions, and outlining the management of systemic and local complications such as fluid overload, air embolism, phlebitis, infiltration, and extravasation.