Acid, Base, Fluid 9/15


Terms in this set (...)

state of equilibrium of the internal environment of the body

Maintained by adaptive responses

Maintenance of volume of body fluids

Nursing must anticipate the potential for alteration in fluid and electrolytes in response to medical disorders
Water content of the Body
60% of the body weight

Solvent for which salts, nutrients and waste are dissolved and transported

Greater in men than women

Older adult:45-55%-therefore react quicker
Infants: 70-80%
Body Fluid Compartments
separated by semipermeable membranes

Intracellular fluid: 2/3 of the body fluid is located within cells

Extracellular fluid: located in the space between cells and lymph

Interstitial fluid: fluid in space between cells
Plasma: liquid part of blood
Transcellular fluid: fluid found in cavities, cerebrospinal, GI fluid, peritoneal fluid, lungs like moisture
ions: electrically charged particles
Cations: positively charged
Anions: negatively charged
Electrolyte Composition
Prevalent cation is potassium
Prevalent anion in phosphate

Prevalent cation is sodium
Prevalent anion is chloride

Prevalent cation is calcium
Mechanisms Controlling Fluid and Electrolyte Movement
Facilitated diffusion
Active transport
Hydrostatic pressure
Oncotic pressure-a form of osmotic pressure exerted by proteins, notably albumin, in a blood vessel's plasma
movement of molecules form high to low
Occurs in liquids solids and gases

Membrane separating two areas must be permeable to diffusing substance

Requires no energy
Facilitated diffusion
Movement of molecules from high to low concentration without energy using specific carrier molecules to accelerate diffusion
EX glucose, sodium potassium, these use carrier protiens
Active Transport
process in which molecules move against concentration gradient, required energy ex sodium potassium pump
movement of water between two compartments by a membrane permeable to water but not solute

Low solute to high solute

Requires no energy
Osmotic pressure
amount of pressure required to stop osmotic flow of water
Determined by concentration of solutes in solution

Hypotonic env: results in cellular swelling

Isotonic env: results in no change

Hypertonic env: results in cellular shrinkage
Hydrostatic pressure
force within a fluid compartment

Major force that pushes water out of the vascular system at capillary level

In blood vessels, hydrostatic pressure is the blood pressure generated by the contraction of the heart
Oncotic Pressure
osmotic pressure exerted by colloids in solution, keeps pressure in vasculature

Protein is a major colloid
Protein molecules attract water, pulling fluid form the tissue to the vascular space

Ex: starving child, big belly, lacks protein to keep fluid from leaking into interstitial space, or think liver patient, thin legs, large belly

Without protein, pressure decreases, fluid leaks out
Fluid movements in capillaries
fluid shifts: plasma to interstitial fluid results in edema

Shifts of interstitial fluids to plasma: occurs with an increase in plasma osmotic or oncotic pressure, may be achieve with compression stockings

Nursing evaluation is key, I and O, body weight
Fluid Spacing
first spacing: normal distribution of fluid in the ICF and ECF compartments

Second spacing: abnormal accumulation of interstitial fluid

Third spacing: (lot of edema) when fluid accumulates in a portion of the body from which it is not easily exchanged with the rest of the ECF, Fluid is trapped

Ascites-the accumulation of fluid in the peritoneal cavity, causing abdominal swelling.

Edema associated with burns or trauma

Peritonitis inflammation of the peritoneum — a silk-like membrane that lines your inner abdominal wall and covers the organs within your abdomen
Regulation of water Balance
hypothalamic regulation

Pituitary regulation

Adrenal cortical regulation

Renal regulation

Cardiac regulation

Gastrointestinal regulation

Insensible water loss: invisible vaporization via lungs and skin
Gerontology Consideration:
structural changes in kidneys decrease ability to conserve water

Less efficient sodium and water regulation

Hormonal changes lead to decrease in ADH and ANP

Loss of subcutaneous tissue leads to increased loss of moisture

Reduced thirst mechanism results in decreased fluid intake

Nurse must assess for these changes and implement treatment accordingly

Summary: lose water (poor kidneys, subcu tissue), lose thrist
Causes of Fluid and Electrolyte Imbalances
Common in most patients with major illness or injury

Directly caused by illness or disease (burns or heart failure)

Results of therapeutic measures (IV fluid replacement or diuretics
Extracellular Fluid Volume Imbalances
Causes ECF volume deficit (Hypovolemia)

Insensible water loss
High fever or heat stroke

Diabetes insipidus

Osmotic diuresis


Gi loss
Vomiting, ng tube suction, diarrhea, fistula drainage


Decrease fluid intake

Third spacing
Clinical Manifestation hypovolemia
low BP, postural hypotension, increase pulse

Restlessness, drowsiness, lethargy, confusion

Thirst, dry mucous membranes

Decrease skin turgor

Decrease cap refill

Decrease urine output, concentrated urine

Increase resp rate

Weakness, dizziness

Weight loss

Seizures, coma
Hypovolemia Nursing Diagnoses
fluid volume deficit

Decreased cardiac output

Risk for deficit fluid volume

Hypovolemic shock

Excess fluid volume-accidentally give too much fluid

Risk for imbalance fluid volume

Ineffective airway clearance

Risk for impaired skin integrity

Disturbed body image

Potential complications: pulmonary edema, ascites
IV Fluids
Hypervolemia Nursing Implementation
I & O

Daily weights

Monitor cardiovascular changes

Resp changes


Skin assessment

Neurological function

Voluntary movement of extremities
Muscle strength

Treatment: remove fluid without changing electrolyte composition or osmolality
Hypervolemia definition and causes
excess fluid volume, big up in the extracellular space

Impaired gas exchange

Risk for impaired skin integrity

Activity intolerance

Disturbed body image

Potential complications: pulmonary edema ascites
Clinical Manifestations Hypervolemia
Jugular vein distention

Dyspnea, crackles, pul edema

Headache, confusion, lethargy

Peripheral edema

Bounding pulse, increase BP


Muscle spasms

Weight gain

Seizure coma
has similar osmolarity as blood
Will remain inside the blood vessel
Useful with hypovolemia and hypotension
.9% normal saline
Osmolarity is less than blood
Pull water from the intravascular system to the interstitial fluid compartments
DSW (.45%) .5 NS (normal saline)
Osmolarity is higher than blood
Pull fluid and electrolytes from intracellular and interstitial places to the intravascular space
Increase urine output, decrease edema, burns
DSNS, DS (.45%).5NS, D50W(used for hypo), D10W (used when need a little sugar boost), 3% NS
Water status on RBC insert image
Peripheral IV lines
superficial lines

For short term use

Need to assess site for signs of infection and infiltration( through vein)
Care for peripheral IVs
Nursing assessment

Nursing interventions for
Stop infusion
Discontinue IV
Notified MD
Replace IV
Document infiltration
Peripherally inserted central catheter
central lines are inserted peripherally but end in the superior vena cave

Long term use: 1 week to 6 months

Flushed with saline and heparin 3cc in small, 10cc in picc

Flush before and after
Porta-Cath insert photo
Sodium Na+
normal values 135-145mEq/L (write previous number so we can know trends)

Main cation in ECF

Maintaining the concentration and volume of ECF and influencing H20 distribution between ECF and ICF

Primary regulator of fluids

GI tract absorbs Na from food
Cause of Hypernatremia
excessive sodium intake
IV fluids
Hypertonic tube feeding
Near drowning

Inadequate water intake

Excessive water loss
High fever
Heat stroke
Prolonged hyperventilation
Diuretic therapy

Disease states
Diabetes insipidus
Primary hyperaldosteronism
Cushing's syndrome
Clinical Manifestations Hypernatremia
With decrease ECF volume
Restlessness, agitation, seizures, and coma
Intense thirst, Dry swollen tongue
Postural Hypotension, weight loss, increased pulse
Weakness, lethargy

With normal or increased ECF volume
Flushed skin
Weight gain, peripheral/pul edema, increased BP

Treat underlying cause
If oral fluids cannot be ingested, IV solution of 5 % dextrose in water or hypotonic saline
Hypernatremia nurse diagnoses
electrolyte imbalance

Riske injury related to altered sensorium and seizures

Risk for fluid volume deficit

Potential complications
Hypernatremia nurse implementation
treat underlying causes

Monitor labs

Promote safety

Monitor weights and I& Os
Causes of Hyponatremia
GI loss- Diarrhea, vomiting, fistula NG suctioning

Renal loss-diuretics, adrenal insufficiency, sodium wasting renal disease

Skin loss-burns, wound damage

Inadequate intake-fasting diets

Excessive water gain

Disease states-SIADH, heart failure, primary hypoaldosteronism
Clinical manifestation of hyponatremia
With decrease ECF volume
Confusion, irritability, apprehension, dizziness, personality changes, tremors, seizures,
Dry mucous membranes
Postural hypotension, decrease jugular venous filling, increase pulse, thread pulse
Cold and clammy skin

With normal or increase ECF volume
Confusion, headaches, apathy, muscle spasms, seizures, coma
Nausea, vomiting, diarrhea, abdominal cramps
Weight gain, increase BO and CVP
Hyponatremia nursing diagnoses
electrolyte imbalance

Risk for acute confusion

Risk for injury to related to altered sensorium and seizures

Risk for fluid volume increase

Potential complications
Nursing implementation hyponatremia
Treat underlying cause

Replace sodium

Fluid restrictions-restrict free water

Monitor labs


I & O

Daily weights
Potassium K+
Normal values 3.5-5 mEq/L

Most important intracellular electrolyte

Main cation in ICF (98%)

K regulates intracellular osmolality and promotes cellular growth

Diet is our source of K
Causes Hyperkalemia
Excess K intake
Rapid parenteral administration
K containing medications
K containing salt substitute

Shifts of K out of the cell
Tissue catabolism (Fever, sepsis, burns)
Tumor lysis syndrome

Failure to eliminate K
Renal disease
K sparing diuretics
Adrenal insufficiency
ACE inhibitors
Clinical Manifestation: Hyperkalemia


Abdominal cramping, diarrhea

Weakness of lower extremities


Irregular pulse

Cardiac arrest

Tall pealed t waves
Prolonged p waves
Widening QRS
Ventricular fibrillation
EKG hyperkalemia insert photo
Nursing Diagnoses hyperkalemia
electrolyte imbalance

Risk for activity intolerance

Risk for injury related to muscle weakness

Risk for fluid volume increase

Potential complications
Hyperkalemia Nursing Implementation
Monitor cardiac functions

Monitor labs

Eliminate oral or parenteral k intake

Increase elimination of K
Kayexalate 15 g PO 4 times a day

Force K from ECF to ICF
Sodium bicarbonate 50mEq
Regular insulin
Sometimes albuterol

Iv calcium gluconate
Acid-Base Balance
part of homeostasis

Acid-contains hydrogen + ions

Base-compound accepts hydrogen ions

Measured by arterial blood gases


PaCO2- 35-45 mmHG

HCO3- 22-26 mEq per liter
Acid Base Regulation
Buffer systems-react immediately

Respiratory mechanisms
Respond in minutes

Renal mechanisms
Respond in 2-3 days
Acid base imbalances
Respiratory Acidosis
Anything that causes hypoventilation
CNS depression to head injury, spina cord injury, narcotics, sedatives or anesthesia
Impair respiratory muscle function to neuromuscular disease
Pulmonary Disorders
Atelectasis, Pneumonia, Pneumothorax, pulmonary edema, bronchial obstruction, large pulmonary embolus, chest wall injury.
Serum ph below 7.5
PaCO2 greater than 4.5 mm HG
Respiratory cause: retention of CO2
Metabolic cause: loss of bicarbonate
Respiratory Alkalosis
Any condition involving hyperventilation
Psychological responses: anxiety or fear
Increased metabolic demands, fever, sepsis pregnancy
Medication: respiratory stimulants
Central nervous system lesions
Serum pH above 7.45
Respiratory cause: blowing off CO2
Metabolic cause: increase in bicarbonate
Metabolic Acidosis
bicarbonate level of less than 22m Eq per L

Ph of less than 7.35

Any condition can increase acid other than CO2;
Renal failure
Diabetic ketoacidosis
Salicylate intoxication
Metabolic alkalosis
bicarbonate level of greater than 26 mEq per L

Ph >7.45

Any condition that can make it more basic
Gastric suction
Excess use of diuretics
High level aldosterone
Insert comparison diagram of respiratory clinical manifestation
Insert diagram metabolic clinical manifestations
Nursing Assessment : Fluid, Electrolyte, Acid-Base imbalance
Head-to-toe physical assessment

Vital signs: temp, pulse, respiration, blood pressure

Daily weight

Fluid intake & output

Laboratory studies
Respiratory Acidosis- resolve respiratory issues, provide manual ventilation, provide 02,

Respiratory Alkalosis-resolve underlying causes
Metabolic Acidosis-resolve underlying causes

Metabolic Alkalosis- can be difficult to treat, IV administration of acid
Fully vs Partial chart
Too much calcium- flabby muscles
Not enough hyperactive muscles
Clinical Manifestation of Hypokalemia
Muscle weakness, leg cramps
Soft, flabby muscles
Parenthesis, decrease reflexes
Weak, irregular pulse
Causes Hypokalemia
K loss
Gi loss

Shifts of K into cell
Increase insulin
Tissue repair
Increase epinephrine

Lack of K intake
Diet to low in K
Failure to include in parenteral fluid if NPO
Nursing Diagnoses Hypokalemia
electrolyte imbalance
Risk for activity intolerance
Risk for injury related to muscle weakness
Risk for fluid volume increase
Potential complications
EKG changes with hypokalemia
Flatten T wave
ST segment depression
Presence if U wave
Prolonged QRS
PVC, Bradycardia
Normal lvls 8.6-10.2 mg per dl
In teeth and bones

Transmission of nerve impulses

Myocardial contraction

Muscle contraction

Body Content:1200g of Ca

Controlled by parathyroid hormone and calcitonin
Nursing implementation Hypokalemia
monitor cardiac functioning
Repletion of K
IV (no more than 10mEq per L)
PO does 20-40 mEq per L

Monitor renal Function-adequate urine output, BUN or Creat
Monitor labs
Causes of hypercalcemia

Multiple myeloma

Malignancies with bone metastasis

Prolonged immobilization

VT D overdose

Thiazide diuretics

Milk-alkali syndrome
Clinical manifestations
Decrease reflexes
Lethargy, weakness

Decreased memory

Confusion, personality changes

Anorexia, nausea, vomiting

Bone pain, fractures

Polyuria, dehydration

Stupor, coma,
EKG changes hypercalcemia
Shortened ST segments
Shortened QT interval
Ventricular dysrhythmias
Diagnosing Hypercalcemia
Potential complication: dysrhythmias

Electrolyte imbalance related to excessive bone destruction

Risk of injury related to neuromuscular and sensorium changes

Risk for activity intolerance related to generalized muscle weakness
Nursing Implementations Hypercalcemia
loop diuretics

IV fluids: Isotonic Saline

Drink 3k-4k mL of fluid

Calcitonin IM
Monitor I & Os, calcium levels, monitor EKGs
Hypocalcemia Causes
primary hypoparathyroidism

Chronic kidney disease

Elevated Phos

Vit D deficiency

Acute pancreatitis

Loop diuretic

Chronic alcoholism


Decreased serum albumin
Clinical manifestation insert picture
increased fatigue

Depression, anxiety confusion

Numbness and tingling

Hyperreflexia, muscle cramps,

Chvosteks sign

Trousseau sign

Laryngeals spasms

Tetany seizures
Hypocalcemia EKG
Elongated ST segments
Prolonged QT intervals
Ventricular tachycardia
potential complications: Dysthymias

Fractures, respiratory arrest
Ineffective breathing patterns related to laryngospasms

F & E imbalance

Risk for injury related to tetany and seizure

Acute pain related to sustained muscle contractions
Nursing implementation of hypocalcemia
treat underlying cause

Replete Ca IV

Oral Ca supplements

Increased Ca in diet

Monitor respiration status

Monitor EKGs

Monitors Ca levels

Treat pain and anxiety
Normal values 2.4-4.44 mg per dl

Second most abundant element in the body

Essential for functions of :muscle, RBCS, nervous system

Involved in the acid-base buffering

Mitochondrial formations of ATP

Cellular uptake and use of glucose

Reciprocal relationship exists between phos and calcium
Hyperphosphatemia cause
renal failure

Chemo drugs
Enemas containing
Excessive ingestion(milk, phos contain laxatives)
Sickle cell anemia
Clinical Manifestations of hypophosphatemia
Numbness and tingling in extremities and mouth
Hyperreflexia, muscle cramps
Tetany seizures
Nursing Diagnosis hyperphosphatemia
Look up
Nursing Implementations
Treat underlying cause-restrict foods high in phosphate,
monitors phos and ca levels


Causes of Hypophosphatemia
malabsorption syndrome


Glucose or insulin therapy

Total parenteral nutrition

Alcohol withdrawal

Phosphate binding antacids

Recovery form diabetic ketoacidosis

Respiratory alkalosis
Clinical manifestations
CNS depression

Muscle weakness

Polyneuropathy seizures


Nursing Diagnosis hypophosphatemia
Look up
nursing implementation hypophosphatemia
Monitoring of Ca and Phos levels

Repletion oral supplements, neutral Phos

IV repletion for very low phosphate levels: sodium Phos, K Phos
homeostasis of calcium and Phosphate
look up relationship
normal values:1.5-2.5 mEq per L

Second most abundant intracellular cation

Coenzyme in the metabolism of carbs and proteins

Role in normal Ca and K balance

50-60 percent of mag is found in bone
Hypermagnesmia Causes
Renal failure

Adrenal insufficiency

Excessive administration of mag for eclampsia

Tumor lysis syndrome

Diabetic ketoacidosis
Clinical manifestation Hypermagnesmia
lethargy, drowsiness,
Nausea, vomiting

Diminishing deep tendon reflexes

Flushes warm skin

Decreased pulse, BP

Muscle weakness

Nursing implementation hypermagnesemia

Decrease medication containing mg

Limit mg congaing foods: green veg, nuts, bananas, oranges, penut butter, chocolate

Promote urinary excretion-lasix
Hypermagnesemia diagnosis
Look up


Chronic alcoholism

Malabsorption syndrome

Prolonged malnutrition

Increase urine output

NG section

Poorly controlled diabetes
Hypomagnesemia clinical manifestations

Tremors, seizures

Hyperactive deep tendon reflexes


Increase pulse and BP

Muscle cramping
Nursing diagnosis hypomagnesemia
look up
Hypomagnesemia nursing implementation
treat underlying causes
Replete Mag

Monitor VS

Monitor EKG
She said
Know how to treat for all fluid and electrolyte imbalances
Electrolytes are base for other medications

Hypomagnesemia-avoid citrus fruit, lemonade doesn't count