This document discusses fluid and electrolyte balance, imbalances, and treatment. It covers maintaining balance through the kidneys, adrenal glands, and ADH hormone. Common imbalances are fluid volume deficit and excess. Fluid volume deficit can be isotonic, hypertonic, or hypotonic and is assessed through various systems before being treated with oral or IV fluid replacement. Fluid volume excess can also be isotonic, hypertonic, or hypotonic and is assessed in a similar way before being treated with diuretics and fluid restriction.