Chapter 17 of Lewis’s Medical-Surgical Nursing (12th Edition) provides an in-depth exploration of fluid, electrolyte, and acid-base imbalances, conditions that frequently accompany major illnesses, surgical stress, and medical treatments. The chapter begins by explaining the critical role of body fluids in homeostasis, the distribution between intracellular and extracellular compartments, and mechanisms like diffusion, osmosis, active transport, and hydrostatic and oncotic pressure that regulate fluid shifts. It discusses fluid volume imbalances, highlighting hypovolemia and hypervolemia, their causes, manifestations, and interprofessional management. Detailed sections address sodium (hypernatremia and hyponatremia), potassium (hyperkalemia and hypokalemia), calcium (hypercalcemia and hypocalcemia), magnesium (hypermagnesemia and hypomagnesemia), and phosphate (hyperphosphatemia and hypophosphatemia) imbalances, with emphasis on etiology, clinical signs, and nursing interventions. The chapter also explains acid-base regulation via buffer systems, the respiratory system, and renal function, before analyzing disorders such as metabolic acidosis, metabolic alkalosis, respiratory acidosis, and respiratory alkalosis, including ABG interpretation and compensatory mechanisms. Nursing management focuses on patient safety, daily weights, intake and output, cardiovascular and respiratory monitoring, skin care, oral rehydration, and IV therapies. The chapter concludes with guidelines for central venous access devices (CVCs, PICCs, implanted ports) and IV fluid solutions, emphasizing their indications, complications, and nursing responsibilities. Together, this comprehensive content equips nurses with the knowledge to assess, prevent, and correct life-threatening electrolyte, fluid, and acid-base imbalances. 📘 Read full blog summaries for every chapter: https://lastminutelecture.com 📘 Have a book recommendation? Submit your suggestion here: https://forms.gle/y7vQQ6WHoNgKeJmh8 Thank you for being a part of our little Last Minute Lecture family! ⚠️ Disclaimer: These summaries are created for educational and entertainment purposes only. They provide transformative commentary and paraphrased overviews to help students understand key ideas from the referenced textbooks. Last Minute Lecture is not affiliated with, sponsored by, or endorsed by any textbook publisher or author. All textbook titles, names, and cover images—when shown—are used under nominative fair use solely for identification of the work being discussed. Some portions of the writing and narration are generated with AI-assisted tools to enhance accessibility and consistency. While every effort has been made to ensure accuracy, these materials are intended to supplement—not replace—official course readings, lectures, or professional study resources. Always refer to the original textbook and instructor guidance for complete and authoritative information.