Home‎ > ‎Nursing Notes‎ > ‎Medical & Surgical Nursing‎ > ‎

Acid-Base Imbalances




Acid–base imbalance is an abnormality of the human body’s normal balance of acids and bases that causes the plasmapH to deviate out of the normal range (7.35 to 7.45).


I. Respiratory Alkalosis

Respiratory Alkalosis is an acid-base imbalance characterized by decreased partial pressure of arterial carbon dioxide and increased blood pH

Contributing Factors:
  • hyperventilation due to anxiety
  • hypoxia
  • improper mechanical ventilation
  • fever
  • salicylate poisoning
Signs and Symptoms/ Clinical Manifestations:
  • light headedness
  • inability to concentrate
  • convulsions
  • positive Chvostek’s sign nausea and vomiting
  • muscle twitching
  • Labs indicated: arterial blood gas (ABG) studies reveal abnormal values: pH above 7.45 and partial pressure of carbon dioxide below 35 mmHg.
Nursing Diagnoses:
  • Impaired gas exchange
  • Ineffective Breathing pattern
  • Ineffective Tissue perfusion
  • Acute confusion
  • Risk for injury
Medical Management / Nursing Interventions:
  • Institute safety measures for the patient with vertigo or the unconscious patient.
  • Encourage the anxious patient to verbalize fears
  • Administer sedation as ordered to relax the patient
  • Keep the patient warm and dry
  • Encourage the patient to take deep, slow breaths or breathe into a brown paper bag (inspire CO2).
  • Monitor vital signs
  • Monitor ABGs, primarily PaCO2; a value less than 35 mmHg indicates too little CO2 (carbonic acid)

II. Respiratory Acidosis


Respiratory Acidos is is an acid-base imbalance characterized by increased partial pressure of arterialcarbon dioxide and decreased blood pH.

Contributing Factors:
  • chronic obstructive respiratory disorders
  • chest wall trauma, pulmonary edema, atelactasis, pneumothorax, drug overdose, pneumonia, Guillain-Barre syndrome
  • any condition that results in hypoventilation
  • Signs and Symptoms/ Clinical Manifestations:
  • increased pulse and respiratory rate
  • Increased blood pressure
  • mental cloudiness and feeling of fullness in head
  • weakness
  • dull headache
  • Labs indicated: arterial blood gas (ABG) studies reveal abnormal values: pH below 7.35 and partial pressure of carbon dioxide above 45 mmHg.
Nursing Diagnoses:
  • Impaired gas exchange
  • Ineffective Breathing pattern
  • Ineffective Tissue perfusion
  • Acute confusion
  • Risk for injury
Medical Management / Nursing Interventions:
  • Institute safety measures
  • Assist with positioning
  • Monitor I&O and administer fluids as ordered
  • Administer oxygen and medications for order; monitor hourly vital signs and respiratory status (may requires mechanical ventilation)
  • Monitor arterial blood gases (ABGs); pH, PaCO2, HCO3

III. Metabolic Alkalosis

Metabolic Alkalosis is an acid-base imbalance characterized by excessive loss of acid or excessive gain of bicarbonate.

Contributing Factors:
  • vomiting
  • gastric suctioning
  • excessive intake of alkali (antacids, baking soda)
Signs and Symptoms/ Clinical Manifestations:
  • tingling of fingers
  • dizziness, confusion
  • tetany
  • slow, shallow respirations, possibly apnea
  • Labs indicated: arterial blood gas (ABG) studies reveal abnormal values: pH above 7.45 and HCO3 above 26 mEq/L; urine chloride concentrations help to differentiate between vomiting or diuretic ingestion or one of the causes of mineralocorticoid excess.

IV. Metabolic Acidosis


Metabolic Acidosis is an acid-base imbalance resulting from excessive absorption or retention of acid or excessive excretion of bicarbonate.

Contributing Factors:
  • ketoacidosis
  • lactic acidosis
  • prolonged fasting
  • salicylic poisoning
  • oliguric renal disease
  • abnormal bicarbonate losses, which can occur in loss of fluid from the lower GI tract from surgery, drains or severe diarrhea
Signs and Symptoms/ Clinical Manifestations:
  • headache
  • drowsiness and confusion
  • weakness
  • increased respiratory rate and depth
  • nausea and vomiting
  • diminished cardiac output with pH below 7, which results in hypotension, cold clammy skin and cardiac arrhythmias.
  • Labs indicated: arterial blood gas (ABG) studies reveal abnormal values: pH below 7.35 and HCO3 below 22 mEq/L; serum potassium level reveals hyperkalemia

image by : http://compepid.tuskegee.edu
Comments