Guided Lecture Notes
Chapter 6: Disorders of Fluid, Electrolyte, and Acid-Base Balance
Learning Objective 1.
Define the terms electrolyte, ion , and nonelectrolyte .

Differentiate between electrolytes and nonelectrolytes.

Describe the relationship of electrolytes to ions.

Define anion and cation.

Discuss the importance of electrolytes to cell function, and explain how they are measured.

State the normal values for electrolyte concentrations (refer to Table 6-1 ).
Learning Objective 2.
Differentiate intracellular from extracellular compartments in terms of distribution and composition of water, electrolytes, and other osmotically active solutes.

Describe the composition of intracellular and extracellular cell compartments
(refer to PowerPoint Slide 2 and Fig. 6-1 ).

Identify the components that are measured clinically.
Learning Objective 3.
Discuss diffusion and osmosis and how the two processes differ.

Using examples, explain diffusion and osmosis (refer to PowerPoint Slide 3 and
Fig. 6-2 ).

Discuss the relationship between tonicity and osmosis (refer to Fig. 6-3 ).
Learning Objective 4.
Cite the rationale for the use of concentration rather than absolute values in describing electrolyte content of body fluids.

List common units used to express electrolyte concentration.
Learning Objective 5.
Describe the control of cell volume and the effect of isotonic, hypotonic, and hypertonic solutions on cell size.


Explain how isotonic solutions are equivalent to ICF.

Describe what will happen to cells that are exposed to hypertonic and isotonic solutions.
Learning Objective 6.
Describe factors that control fluid exchange between the vascular and interstitial fluid compartments, and relate them to the development of edema and third spacing in extracellular fluids.

List the four forces that control the movement of water between the capillary and interstitial spaces, and give examples of each (refer to PowerPoint Slide 6 ).

Using examples, describe the physiologic mechanisms that lead to the development of edema (refer to Chart 6-1 ).

Explain what is meant by third-space fluid accumulation, and define hydrothorax, ascites, and effusion.
Learning Objective 7.
Describe the manifestations and treatment of edema.

Describe the clinical presentation of edema, and explain how to assess the degree of edema (refer to PowerPoint Slide 10 and Fig. 6-5 ).

Discuss the treatments for edema.
Learning Objective 8.
Describe the relationship between body water and extracellular sodium concentration.

Describe the % composition of body water and sodium in ICF and ECF.

Define total body water (TBW), and list factors that cause it to increase or decrease (refer to Fig. 6-6 ).
Learning Objective 9.
Discuss sources of both sodium loss and sodium gain.


Define the normal extracellular sodium level in mEq/L (refer to PowerPoint
Slide 9 ).

Identify factors that cause sodium to be gained or lost.
Learning Objective 10.
Describe the causes, manifestations, and treatment of psychogenic polydipsia.

Discuss the physiologic mechanisms that regulate body water (refer to Fig. 6-7 ).

Define polydipsia.

Identify the psychiatric disorder with which psychogenic polydipsia is associated, and list factors that may exacerbate the condition.

Explain the physiologic result of psychogenic polydipsia, and discuss its treatment.
Learning Objective 11.
Compare the pathophysiology, manifestations, and treatment of diabetes insipidus and the syndrome of inappropriate antidiuretic hormone.

Describe the cause of DI.

Identify the two types of DI (refer to PowerPoint Slide 15 ).

Describe signs and symptoms of DI, and list treatment options.

Identify the cause of SIADH, and differentiate between transient and chronic conditions (refer to PowerPoint Slide 15 ).

Describe signs and symptoms of SIADH, and list treatment options.
Learning Objective 12.
Compare and contrast the causes, manifestations, and treatment of isotonic fluid volume deficit, isotonic fluid volume excess, hyponatremia with water excess, and hypernatremia with water deficit (refer to Fig. 6-8 ).

Give the normal range for sodium in ECF (refer to PowerPoint Slide 16 ).


Identify the two main categories of disorders of sodium and water balance, and explain where they are most likely to occur.

Describe the causes, signs and symptoms, diagnosis, and treatment of isotonic fluid volume deficit (refer to Table 6-3 ).

Describe the causes, signs and symptoms, diagnosis, and treatment of isotonic fluid volume excess (refer to Table 6-3 ).

Describe the causes, signs and symptoms, diagnosis, and treatment of hyponatremia (refer to PowerPoint Slide 16 and Table 6-4 ).

Describe the causes, signs and symptoms, diagnosis, and treatment of hypernatremia (refer to PowerPoint Slide 16 and Table 6-4 ).
Learning Objective 13.
Characterize the distribution of potassium in the body, and explain how extracellular potassium levels are regulated in relation to body gains and losses.

Describe the composition of potassium in ICF and ECF, giving its normal value in mEq/L (refer to PowerPoint Slide 18 ).

Using examples, explain renal regulation of potassium, as well as extracellular to intracellular shifts (refer to Fig. 6-9 ).
Learning Objective 14.
State the causes of hypokalemia and hyperkalemia in terms of altered intake, output, and transcellular shifts.

Describe the causes of hypokalemia.

Describe the causes of hyperkalemia.
Learning Objective 15.
Relate the functions of potassium to the manifestations of hypokalemia and hyperkalemia.


Explain the functions of potassium in the cell (refer to PowerPoint Slide 18 ).

Describe how potassium levels affect resting membrane potential (RMP) (refer to
PowerPoint Slides 22–24 and Fig. 6-10 ).

Describe the signs and symptoms of hypokalemia, and explain how they relate to diminished levels of potassium (refer to Table 6-5 ).

Describe the signs and symptoms of hyperkalemia, and explain how they relate to an excess of potassium (refer to Table 6-5 ).
Learning Objective 16.
Describe methods of diagnosis and treatment of hypokalemia and hyperkalemia.

Explain how hypokalemia is diagnosed and treated.

Discuss precautions associated with potassium infusion.

Explain how hyperkalemia is diagnosed and treated.
Learning Objective 17.
List and describe the three forms of extracellular calcium that exist in the body.

Describe where calcium is found in the body.

Identify the three forms of extracellular calcium, and their % contribution to total extracellular calcium (refer to Fig. 6-12 ).
Learning Objective 18.
Describe the associations among intestinal absorption, renal elimination, bone stores, and the function of vitamin D and parathyroid hormone in regulating calcium and phosphate.

Trace the path of calcium from its entrance into the body through intestinal absorption to its storage and eventual elimination through the renal system (refer to PowerPoint Slide 28 and Fig. 6-14 ).


Identify the main sources of dietary calcium.

Explain the importance of vitamin D and parathyroid hormone in the absorption of calcium and phosphate.
Learning Objective 19.
Describe hypocalcemia and hypercalcemia in relation to causes, manifestations, diagnosis, and treatment.

Give the normal value of serum calcium in mg/dL, and explain its function (refer to PowerPoint Slide 27 )

Describe the causes, signs and symptoms, diagnosis, and treatment of hypocalcemia (refer to Table 6-6 ).

Describe the causes, signs and symptoms, diagnosis, and treatment of hypercalcemia (refer to Table 6-6 ).
Learning Objective 20.
Describe the mechanisms of magnesium regulation and relate them to the causes of hypomagnesemia and hypermagnesemia.

Describe where magnesium is found in the body, and give the normal serum concentration in mg/dL (refer to PowerPoint Slide 30 ).

Explain the importance of magnesium to body function (refer to PowerPoint
Slide 30 ).

Trace the path of magnesium from its entrance into the body through intestinal absorption to elimination through the renal system, explaining its regulation by the kidneys.

Identify the main sources of dietary magnesium.

Identify causes of hypomagnesemia and hypermagnesemia.

Learning Objective 21.
Relate the functions of magnesium to the manifestations of hypomagnesemia and hypermagnesemia.

Describe the signs and symptoms of hypomagnesemia, and explain how they relate to diminished levels of magnesium (refer to Table 6-7 ).

Describe the signs and symptoms of hypermagnesemia, and explain how they relate to an excess of magnesium (refer to Table 6-7 ).
Learning Objective 22.
Discuss the diagnosis and treatment of hypomagnesemia and hypermagnesemia.

Describe how a diagnosis of hypomagnesemia is made, and discuss treatment options.

Describe how a diagnosis of hypermagnesemia is made, and discuss treatment options.
Learning Objective 23.
Characterize an acid and a base.

Describe an acid and a base with regard to their ability to accept or donate hydrogen ions.

Give the normal pH of ECF (refer to PowerPoint Slide 35 ).
Learning Objective 24.
Cite the source of metabolic acids.

Identify the inorganic acids that are the result of dietary protein metabolism.

Describe the net result of acid and base production.
Learning Objective 25.
Describe the three forms of carbon dioxide transport and their contribution to acid-base balance (refer to PowerPoint Slide 36 ).

List the three ways in which calcium is transported in the circulation, and explain how carbonic anhydrase catalyzes the reaction between CO
2
and water.


Give the normal serum level of PCO
2
.

Explain how to calculate bicarbonate levels using PCO
2
.
Learning Objective 26.
List the three major mechanisms of pH regulation.

Using examples, cite the mechanisms by which intracellular and extracellular buffering systems, the lungs, and the kidneys control pH levels (refer to
PowerPoint Slide 41 and Fig. 6-15 ).
Learning Objective 27.
Describe the intracellular and extracellular mechanisms for buffering changes in body pH.

Define buffer system.

Identify the three major buffer systems that regulate the pH of body fluids, and explain their mechanisms of action.
Learning Objective 28.
Compare the role of the kidneys and respiratory system in regulation of acid-base balance.

Explain the relationship between PCO
2
levels and pH, describing how ventilation patterns affect PCO
2
levels (refer to PowerPoint Slides 36 and 37 ).

Explain the relationship between HCO
3
-
levels and pH (refer to PowerPoint
Slides 42 and 43 ).

Compare the response times of the lungs and kidneys when adjusting pH levels.
Learning Objective 29.
Explain how potassium and hydrogen ions and how bicarbonate and chloride ions interact in pH regulation.

Describe how the effects of potassium–H
+
exchange and the levels of HCO
3
-
and
Cl
– affect pH.

Learning Objective 30.
Define the terms acidosis and alkalosis .

Describe the terms arterial blood gas (ABG), acidosis , and alkalosis .

Give normal ABG values.
Learning Objective 31.
Define metabolic acidosis, metabolic alkalosis, respiratory acidosis, and respiratory alkalosis.

Using examples, interpret ABGs using the terms metabolic acidosis, metabolic alkalosis, respiratory acidosis , and respiratory alkalosis (refer to PowerPoint
Slides 36–37, 42–43, and Table 6-8 ).
Learning Objective 32.
List common causes of metabolic and respiratory acidosis and metabolic and respiratory alkalosis.

Using examples, list causes of metabolic and respiratory acidosis and metabolic and respiratory alkalosis.
Learning Objective 33.
Contrast and compare the clinical manifestations and treatment of metabolic and respiratory acidosis and of metabolic and respiratory alkalosis.

Describe the signs, symptoms, and treatment of metabolic acidosis (refer to Table
6-9 ).

Describe the signs, symptoms, and treatment of respiratory acidosis (refer to
Table 6-10 ).

Describe the signs, symptoms, and treatment of metabolic alkalosis (refer to
Table 6-9 ).

Describe the signs, symptoms, and treatment of respiratory alkalosis (refer to
Table 6-10 ).