Fluid and Electrolytes Flashcards
What are the three adaptive mechanisms for acid base imbalance?
- Chemical Buffer System
- Respiratory System
- Renal system
What is the primary regulator of acid base imbalance?
chemical buffer system
How fast is the chemical buffer system?
immediate actions
How does the chemical buffer system work?
chemicals that combine with acids and bases to minimize pH change
What is this?
Acidosis
What is this?
Alkalosis
What is the secondary system for acid base imbalance?
respirarory system
How long does the respiratory system take to respond?
minutes
What is the action of the respiratory system on acid base imbalance?
elimination or retention of carbon dioxide
What is the other secondary system for acid base imbalance?
renal system
How long does the renal system take to respond to acid base imbalance?
2-3 days
What is the renal system’s response to acid/base imbalance?
secretion or reabsorption of hydrogen and bicarbonate
How do you determine acid base imbalance?
arterial blood gas analysis
What does arterial blood gas assess?
- Acid/Base Balance
- Need for oxygen therapy
- Change in oxygen therapy
pH
7.35-7.45
paCo2
35-45mm Hg
HCO3
24-30mEq/L
paO2
75-100mm Hg
O2 sat
92-100%
What should you remember to indicate with ABG sample?
the use of O2
What should you avoid changing 20 minutes prior to obtaining ABG sample?
O2 therapy
What syringe should you use for ABG sample?
heparinized syringe
Why is it especially important to expel air bubbles with an ABG sample?
air bubbles contain gases that can mess with the results of test
What should be done after ABG sample has been taken?
put sample on ice and/or transfer immediately to lab
What should you apply after ABG sample?
pressure to artery for 5 minutes
Step One of Three Step Method
Look at pH
If >7.45 alkalosis
If <7.35 acidosis
Step Two in Three Step Method
Look at the pCO2
Respiratory conditions will have a change in the paCo2
Metabolic conditions - no change
Respiratory conditions - opposite pattern
ROME
Respiratory Opposite Metabolic Equal
pH UP PCO2 DOWN
Respiratory Alkalosis
pH DOWN PCO2 UP
Respiratory Alkalosis
pH UP HCO3 UP
Metabolic Alkalosis
pH DOWN HCO3 DOWN
Metabolic Acidosis
Step Three in Three Step Method
Look at the HCO3
Metabolic conditions will have a change in HCO3
Respiratory Acidosis
- Shallow Respirations
- Pain
- Narcotics
- Atelectasis
- Pneumonia
- COPD
- Asthma
Respiratory Acidosis Assessment
- Shallow Respirations
- Hypoxia
- Mental Changes
- Disorientation
- Drowsiness
- Dizziness
- Flushed, Warm Skin
- Weakness
Respiratory Acidosis Nur Dx
- Impaired Gas Exchange
- Disturbed Thought Processes
- Activity Intolerance
- Risk for injury
Respiratory Acidosis Interventions
- Assess
- Treat cause of shallow respirations
- TCDB
- Ambulate
- Treat Pain
- Reduce narcotic dose
- O2
- Protect from injury
Respiratory Acidosis
- Fast Respirations
- Anxiety
- Fever
- Respiratory Infections
- Pain
Respiratory Alkalosis Assessment
- Lightheadedness
- Confusion
- Teachycardia
- Numbness in extremities
- SOB
- Anxiety
Respiratory Alkalosis Nur Dx
- Ineffective Breathing Pattern
- Disturbed Thought Processes
- Risk for Injury
Respiratory Alkalosis Interventions
- Assess
- Treat underlying cause of hyperventilation
- Encourgae slow breathing
- Breathing into a paper bag
- Sedatives
- Protect from injury
Below Waist?
Loss of Base (poop)
Above waist?
Loss of acid (throw up)
Metabolic Acidosis
- Loss of intestinal contents
- Diarrhea
- Diabetes
- Renal Failure
Metabolic Acidosis Asessment
- Kussmaul Respirations
- Weakness
- Nausea and Vomiting
- Abdominal pain
- CNS symptoms
- Headache
- Confusion
- Drowsiness
Nursing Dx Metabolic Acidosis
- Deficient Fluid Volume
- Risk for Injury
Metabolic Acidosis Interventions
- Assessment
- Treat underlying cause
- Give IV sodium bicarbonate
- Protect from injury
Metabolic Alkalosis
- Loss of gastric acid contents
- Vomiting
- NG suction
- Diuretics
Metabolic Alkalosis Assessment
- CNS Symptoms
- Dizziness
- Confusion
- Irritability
- Tetany
- Tingling in extremities
- Tachycardia
- Hypoventilation
Metabolic Alkalosis Nur Dx
- Deficient Fluid Volume
- Risk for Injury
Metabolic Alkalosis Interventions
- Assessment
- Treat underlying cause
- IV fluid replacement
- Protect from injury
What % of the body is water?
50-60%
Older adult water %
45-55%
Infant water %
70-80%
Who is at a higher risk for fluid problems?
elderly people and infants
How much body water is located within the cells (intracellular fluid)
2/3
What does water do in the body?
regulates body temperaturre, lubricates joints and membranes and is a medium for food digestion
How much does one liter of water weigh?
2.2 lb or 1 kg
Fluid spacing
distribution of water
First Spacing
describes the normal distribution of fluid in the ICF and ECF compartments
Second Spacing
an abnormal accumulation of interstitial fluid, edema
Third Spacing
Occurs when fluid accumulates in a portion of the body (trancellular fluid) from which it is not easily exhanged with the rest of the ECF. Third spaced fluid is trapped and unavailable for functional use
Why are perioperative patients at risk for the development of fluid and electrolyte imbalances?
because of restriction of oral intake, GI prep, blood volume loss, fluid shifts
Hypovolemia is
ECF deficient
Hypervolemia is
ECF excess
Dehydration
the loss of pure water alone without corresponding loss of sodium
Why might fluid volume excess occur?
excessive intake of fluids, abnormal retention of fluids, or a shift of fluid from interstitial fluid into plasma fluid
What might be forms of therapy for fluid volume excess?
diuretics and fluid restriction
ECF volume excess signs and symptoms
full, bounding pulse, distended neck veins, increased blood pressure
Mild to moderate fluid volume deficit
sympathetic nervous system stimulation of the heart and peripheral vasoconstriction. orthostatic hypotension
Severe fluid volume deficit signs and symptoms
weak, thready, pulse that is easily obliterated as well as flattened neck veins, shock
ECF excess respiratory changes
pulmonary congestion and pulmonary edema as increased hydrostatic pressure in the pumonary vessels forces fluid into the alveoli
ECF excess resp. symptoms
SOB, irritative cough, moist crackles
ECF deficit resp. changes
increased resp. rate due to decreased tissue perfusion and resultant hypoxia
ECF excess neurologic changes
cerebral edema
ECF deficit neurologic changes
alteration in sensorium secondary to reduced cerebral tissue perfusion
Why does edemous skin feel cool?
because of the fluid accumulation and a decrease in blood flow secondary to the pressure of the fluid
Why should the patient with nasogastric suction not be allowed to drink water?
It will increase the loss of electrolytes. Water causes diffusion of electrolytes into the gastric lumen from mucosal cells; the electrolytes are then suctioned away.
What is the main cation of the ECF?
sodium
What does sodium do?
plays a major role in maintaining the concentration and volume of the ECF