1 Fluid and electrolyte imbalance in surgical patients

Fluid and electrolyte imbalance in surgical patients

1. Introduction to Fluids &
Electrolytes

2. Learning Objective
On completion of this chapter, the learner will be able to:
1. Differentiate between osmosis, diffusion, filtration, and
active transport.
2. Describe the role of the kidneys, lungs, and endocrine
glands in regulating the body’s fluid composition and
volume.
3. Identify the effects of aging on fluid and electrolyte
regulation.
4. Plan effective care of patients with the following
imbalances: fluid volume deficit and fluid volume excess;
sodium deficit (hyponatremia) and sodium excess
(hypernatremia); potassium deficit (hypokalemia) and
potassium excess (hyperkalemia).
 .

3. 5. Describe the etiology, clinical manifestations,
management, and nursing interventions for the
following imbalances: calcium deficit (hypocalcemia)
and calcium excess (hypercalcemia); magnesium
deficit (hypomagnesemia) and magnesium excess
(hypermagnesemia); phosphorus deficit
(hypophosphatemia) and phosphorus excess
(hyperphosphatemia); chloride deficit (hypochloremia)
and chloride excess (hyperchloremia).
6. Explain the role of the lungs, kidneys, and chemical
buffers in maintaining acid–base balance.
7. Compare metabolic acidosis and alkalosis with
regard to causes, clinical manifestations, diagnosis,
and management.

4. 8. Compare respiratory acidosis and alkalosis
with regard to causes,
clinical manifestations, diagnosis, and
management.
9. Interpret arterial blood gas measurements.
10. Demonstrate a safe and effective
procedure of venipuncture.
11. Describe measures used for preventing
complications of intravenous therapy

5. Nursing Care is directed toward:
Assessing for clients at risk
Monitoring clients for EARLY manifestations
Implement collaborative and nursing
interventions to prevent or correct imbalances
What segment of the life span is at highest
risk of fluid imbalances?

6. Fluid Compartments
Intracellular (ICF) (2/3 of the fluid)
fluids contained withinthe cells
Extracellular (ECF) (1/3 of the fluid)
(Remember blood tests measure extracellular fluid only –
that’s why sodium is high and potassium is low!)
Interstitial(betweenthe cells)
Intravascular (plasma)
arteries, veins, capillaries
Transcellular
misc: urine, digestive secretions, perspiration etc.
Theoretical Third Space: trapped ECF in actual or
potential body space due to disease or injury
Important in burns, shock and cardiovascular

7. Movement of Body Fluids: Important
Concept
Body fluids are not static. Fluids &
electrolytes shift from compartment to
compartment.
Emphasis is always on maintaining
homeostasis

8. FLUID MOVEMENT:
review & see Table 11-2, p.
145 (Iggy)
Diffusion
Osmosis
Filtration
Active Transport

9. Osmosis
Movement of wateracross a semi-permeable
membrane from an area of low solute
concentration (lots of water) to an area of
high solute concentration (less water) until
even distribution (homeostasis) is achieved
Osmolarity = number of milli-osmoles in liter
of solution
Normal = 270 –300 (or 275 –295)
Osmolality = number of mill-osmoles in
kilogram of solution

10. Isotonic Fluids
example: normal saline 0.9% NaCl
No net fluid (water)
shifts occur because
the fluids are EQUALLY
concentrated

11. Hypotonic Fluids
example: 0.45% NaCl
When a LESS
concentrated fluid is
placed next to a MORE
concentrated solution,
watermoves to MORE
concentrated solution
to equalize the
solutions

12. Hypertonic Fluids
example: 3% NaCl
When a MORE
concentrated fluid is
placed next to a LESS
concentrated solution,
watermoves to the
MORE concentrated
solution to equalize the
solutions

13. Body Fluids
Sources of fluid intake
ingested fluids/foods
water as byproduct of metabolism
Fluid Loss
Urine
Respiration
Perspiration
Gastrointestinal tract

14. KIDNEY FUNCTIONS
Regulate fluid volume and osmolality
by selectively retaining & excreting fluids
Regulate electrolyte levels
by selectively retaining & excreting e-lytes
Regulate pH (acid/base balance)
by selectively retaining & excreting H+
Excrete metabolic wastes & toxic substances

15. THE NEPHRON

16. REGULATORY MECHANISMS
THIRST
KIDNEYS
Kidney Function
HORMONES
Renin-Angiotensin-Aldosterone
Anti-Diuretic Hormone
Parathormone

18. Anti-Diuretic Hormone
(think beer)

19. Parathyroid Hormone
Important for Calcium and Phosphorus
balance
Where are the parathyroid glands????

20. Dehydration
Isotonic dehydration: water & electrolytes lost
in equal proportions
Hypertonic dehydration: water loss exceeds
electrolyte loss
Hypotonic dehydration: electrolyte loss
exceeds water loss

21. Dehydration Etiology
Isotonic: inadequate fluid intake, fluids shifts
between compartments, excessive loss of
body fluids
Hypertonic: excessive perspiration,
hyperventilation, fever, diarrhea, ketoacidosis
Hypotonic: chronic illness such as renal
failure, excessive ingestion hypotonic fluids
(babies & water!)

22. DEHYDRATION: FLUID VOLUME
DEFICIT nsg dx
PATHOPHYSIOLOGY
Loss of GI fluids (vomiting, diarrhea, NG
suctioning, fistulas, intestinal drainage, chronic
abuse of laxatives and/or enemas)
Renal loss from diuretics
Water loss from sweating or heat
Blood loss (hemorrhage)
Fluid lost to Third Space (burns, trauma)

23. Dehydration
History (risk factors)
age (very young & very old)
check loss of body weight
history of fluid losses

24. Dehydration
ASSESSMENT/MANIFESTATIONS
Hypotension (decreased systolic, narrowed pulse
pressure, postural hypotension)
Weak, rapid pulse with collapsed veins
Decreased skin turgor, dry membranes
Output > Intake (urine high specific gravity)
Weight loss (1000 ml = 1000gm or 1 kg (2.2
pounds) ** very important

25. Dehydration
Lab Assessment
Serum electrolytes abnormal
Urine specific gravity high (urine is concentrated)
Low central venous pressure
Elevated hematocrit and BUN (blood urea nitrogen)
Caused by more solute, less water =
hemoconcentration

26. Nursing Diagnosis: FLUID VOLUME
DEFICIT
Diet therapy
Oral fluid replacement
Oral rehydration therapy
Pediatric implications to follow on future slide
Drug therapy (varies with type of dehydration)
IV = isotonic (safest)
0.9% NaCl, Ringer’s Lactate
Meds to treat underlying problem

27. Dehydration: Pediatric Implications
Assessment Manifestations
Tend to be subtle & happen quickly
You have a site to observe on an infant that no
longer exists on an adult -??
FONTANELS (anterior & posterior)
Give isotonic fluids
Pedialyte (Gatorade)
Professional Responsibility

28. Community Based Care: Adults &
Children
Health teaching
Diet, drugs, & avoidance in the future
Home care management
control environmental temperature & humidification
family offers fluids frequently (avoid large amounts plain
water in formula fed infant –see under hyponatremia)
Health care resources
Home care visit

29. Overhydration (nsg dx fluid volume excess)
PATHOPHYSIOLOGY
Isotonic = hypervolemia
Hypotonic = excessive fluid (water intoxication)
Hypertonic = rare, excessive sodium intake
SUMMARY: TOO MUCH FLUID!
Steroids, heart failure, cirrhosis of the liver, renal failure,
adrenal gland disorders, excessive intake IV fluids or Sodium
(foods, meds, IV solutions)

30. FLUID VOLUME EXCESS
ASSESSMENT/MANIFESTATIONS
Increased blood pressure
Strong, bounding pulse with neck vein distention
Taut skin turgor, moist mucous membranes
Intake > Output (urine low specific gravity)
Weight gain
Crackles in lung sounds, orthopnea, irritating cough

31. OVERHYDRATION (FVE)
Diagnostic Tests
Electrolytes
Decreased hematocrit & BUN (Blood urea
nitrogen)
Caused by more water, less solute = hemodilution
Increased central venous pressure
Drug therapy
Diuretics
Sodium & Water Restriction

32. Overhydration Nursing Diagnoses
Fluid Volume Excess
as above & assess I&O, vital signs, edema
daily weights
education: sodium
Risk for Impaired Skin Integrity
Potential: Respiratory Insufficiency