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20.0 Module Overview

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ANATOMY & PHYSIOLOGY II · MODULE 20

One leaking filter behind every number

Swollen ankles, a low calcium, and a drift toward acid — three findings, three pieces of advice, one visit. This module builds fluid, electrolyte, and acid-base physiology and shows that all three are the same failure read from different angles.

The findings this module reads together

Cut the salt, take calcium, drink more water. On its own each instruction sounds reasonable. But her edema means fluid has left the vessels for the tissues, and her albumin is low because she is losing it through a damaged filter.

Low albumin drops oncotic pressure, so fluid leaks. Roughly half of blood calcium rides on albumin, so the total calcium reads low while the free calcium is fine. And a failing kidney stops reclaiming bicarbonate, so the pH drifts. Three findings, one leaking filter.

PATIENT CHART · STINA · CHART CLUE #20

  • Exam — Swollen ankles, pitting edema
  • Labs — Low albumin
  • Labs — ‘Low’ total calcium
  • Labs — Low bicarbonate, acid drift

Seven parts, one chart

Each part opens with a finding from Stina’s chart and asks you to commit to a prediction before any video plays, then alternates short videos with H5P activities. Work them in order.

20.1

The Swollen Ankles

Three findings, three errands, and what connects them.

EDEMA

OPEN →

20.2

Fluid Compartments & Water Movement

Where body water sits and what moves it.

FLUID COMPARTMENTS

OPEN →

20.3

Hydrostatic vs Oncotic Pressure

Why low albumin floods the tissues.

STARLING FORCES

OPEN →

20.4

Electrolytes & Corrected Calcium

Why a low total calcium can mean nothing at all.

ELECTROLYTES

OPEN →

20.5

Acid-Base & the Bicarbonate Buffer

The buffer system that holds pH steady.

BUFFERS

OPEN →

20.6

Metabolic Acidosis from a Failing Kidney

What happens when the kidney stops reclaiming base.

ACIDOSIS

OPEN →

20.7

One Filter, Not Three Problems

A scattered handful of lab flags, collapsed into one cause.

CHART CLUE #20

OPEN →

◆

The Evidence Behind the Case

Every step of this module’s reasoning, paired with the peer-reviewed literature behind it.

REFERENCES

OPEN →

What you’ll be able to do

By the end of Module 20 you will be able to:

1

Describe the body’s fluid compartments and the forces that move water between them.

2

Explain hydrostatic and oncotic pressure and predict the effect of hypoalbuminemia.

3

Identify the major electrolytes and calculate an albumin-corrected calcium.

4

Explain the bicarbonate buffer system and the roles of lung and kidney in pH control.

5

Distinguish metabolic from respiratory acid-base disturbances.

6

Integrate edema, hypoalbuminemia, and acidosis as consequences of one renal lesion.

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All pages for Module 20 — Fluids, Electrolytes & Acid–Base Balance

20.0 Module Overview
20.1 The Swollen Ankles That Point Back to the Kidney
20.2 The Body’s Fluid Compartments & Water Movement
20.3 Hydrostatic vs Oncotic Pressure
20.4 The Major Electrolytes & the Albumin-Corrected Calcium
20.5 Acid-Base Balance & the Bicarbonate Buffer System
20.6 Metabolic Acidosis from a Failing Kidney
20.7 One Filter, Not Three Problems
20.8 Conclusion and Assessment
20.9 Evidence Behind the Case

All Modules
  1. Anatomical Language, Membranes & Homeostasis
  2. Just Enough Chemistry
  3. The Cell & Its Transport
  4. Making Cells & Proteins
  5. The Integumentary System
  6. The Skeletal System
  7. The Muscular System
  8. Nervous Tissue & the Senses
  9. The Spinal Cord
  10. The Brain & the Blood–Brain Barrier
  11. The Autonomic Nervous System
  12. Special Senses (in development)
  13. The Endocrine System
  14. Blood
  15. The Heart
  16. Blood Vessels
  17. The Digestive System
  18. The Respiratory System
  19. The Urinary System
  20. Fluids, Electrolytes & Acid–Base Balance
  21. The Reproductive System
  22. The Immune System

List of terms