Metabolic alkalosis occurs when the body contains excessive amounts of base or alkali. This occurs when there is a loss of acid or hydrogen or a gain in bicarbonate. A normal pH level is 7.35 – 7.45. An increase above this range is alkalosis. If bicarbonate (HCO3) increases or carbon dioxide (CO2) decreases, alkalosis will occur. HCO3 is regulated by the renal system, so if the kidneys are functioning properly, hydrogen will be reabsorbed and bicarbonate will be excreted.
Causes of metabolic alkalosis include:
- Hypokalemia (intracellular shift of hydrogen)
- Vomiting (loss of GI acid and hydrogen)
- Excessive use of antacids
- Hypovolemia
- Hyperaldosteronism
- Diuretic use
- Renal failure
- Cystic fibrosis
Clinical manifestations of metabolic alkalosis include:
- Irritability
- Muscle spasms, cramps, or twitching
- Confusion
- Fatigue
- Tremors
- Arrhythmias
- Tingling and numbness
- Seizures
- Coma
To confirm metabolic alkalosis, a physical exam is initiated to evaluate symptoms. ABGs and electrolyte levels are drawn to monitor acid-base balance. Urinalysis may also be performed to confirm the underlying cause.
There is also metabolic acidosis, which occurs when there is an excessive accumulation of acid in the body.
Nursing Process
Nursing management and care for patients with metabolic alkalosis will depend on the cause and severity of the symptoms. For mild cases of metabolic alkalosis, treatment may not be required. Severe cases, however, will require immediate medical attention. Nurses must monitor symptoms and abnormalities, assist with identifying the underlying cause, and initiate appropriate treatment interventions, including intravenous fluids and electrolytes, to correct the imbalance.
Nursing Care Plans Related to Metabolic Alkalosis
Deficient Fluid Volume
Metabolic alkalosis is often caused by severe vomiting, leading to fluid loss and chloride and potassium depletion.
Nursing Diagnosis: Deficient Fluid Volume
Related to:
- Severe vomiting
- Disease process
- Insufficient fluid intake
- Electrolyte imbalances
- Dehydration
As evidenced by:
- Altered skin turgor
- Dry mucous membranes
- Dry skin
- Decreased blood pressure
- Decreased urine output
- Increased body temperature
- Increased heart rate
- Increased urine concentration
- Altered mental status
- Sunken eyes
- Thirst
- Weakness
Expected outcomes:
- Patient will remain free from signs of dehydration, with vital signs within normal limits.
- Patient will demonstrate interventions to manage vomiting and correct fluid loss.
Assessment:
1. Assess for signs of dehydration.
Early signs of dehydration include restlessness, thirst, and inability to concentrate, while the late signs include weak and thready pulse, confusion, and oliguria. These signs occur when the body has compensated fluid loss by moving fluids from interstitial space to the vascular compartment.
2. Assess causative factors contributing to fluid loss.
Fluid loss occurs due to vomiting or diarrhea, which causes metabolic alkalosis due to acid loss, creating an imbalance between acid and bicarbonate. Early identification of the risk factors can help manage and prevent complications.
3. Assess medication use.
Loop diuretics cause the body to excrete potassium which can cause hypokalemia. Excessive consumption of antacids can cause alkalosis since sodium bicarbonate is an ingredient in these medications.
Interventions:
1. Monitor and evaluate electrolyte levels.
Fluid loss in metabolic alkalosis is associated with electrolyte imbalance (hypokalemia and hypochloremia) and will require correction.
2. Administer fluid replacement IV or orally.
If oral fluid intake is difficult due to excessive vomiting, intravenous fluid replacement may be necessary to correct and manage fluid loss in metabolic alkalosis.
3. Monitor the patient’s intake and output.
Decreased urine output can indicate kidney dysfunction, further aggravating metabolic alkalosis if the kidneys cannot reabsorb hydrogen or excrete bicarbonate.
4. Administer medications to treat symptoms.
If severe vomiting or diarrhea is causing hypovolemia and subsequent metabolic alkalosis, administer antiemetics or antidiarrheals to prevent fluid loss.
Acute Confusion
Central nervous system symptoms of metabolic alkalosis can range from confusion to coma and affect muscle contraction and sensations.
Nursing Diagnosis: Acute Confusion
Related to:
- Disease process
- Severe dehydration
- Electrolyte imbalances
As evidenced by:
- Altered psychomotor performance
- Decreased level of consciousness
- Muscle twitching
- Tremors
- Numbness and tingling
- Restlessness
- Seizures
Expected outcomes:
- Patient will remain oriented to person, place, and time.
- Patient will maintain a normal level of consciousness without tremors or muscle weakness.
- Patient will not experience a seizure.
Assessment:
1. Assess the patient’s level of consciousness.
The acid-base balance is a delicate system, and slight alterations in pH can result in irritability, confusion, muscle twitching, and more.
2. Assess laboratory values.
ABGs and electrolytes should be monitored closely if the patient is displaying alterations in mental status.
Interventions:
1. Provide reality orientation.
Keeping the patient oriented as needed can help reduce confusion and encourage cooperation with the treatment regimen.
2. Use therapeutic communication and reassurance.
This promotes a trusting relationship with the patient. Reassure family members that confusion is temporary and explain why it is occurring.
3. Limit exposure to stimuli and keep the environment free from excess noise.
Excessive stimulation can aggravate confusion and irritability in patients with metabolic alkalosis.
4. Provide safety against seizures.
Seizures are a risk with metabolic alkalosis. Keep the patient safe in the event of a seizure by preventing injury or aspiration and maintaining a patent airway.
Deficient Knowledge
Patient education is a vital part of the management of metabolic alkalosis. Patients may need to be made aware of how their medical conditions, medications, or ailments can disrupt their pH.
Nursing Diagnosis: Deficient Knowledge
Related to:
- Unfamiliarity with the medical condition
- Poor health literacy
- Inability to recall information
- Inadequate understanding of information
- Inadequate interest in learning
As evidenced by:
- Inaccurate follow-through of instructions
- Misconceptions about treatment
- Inaccurate statements about alkalosis
- Nonadherence to medication regimen
- Recurrence of alkalosis
Expected outcomes:
- Patient will verbalize an understanding of metabolic alkalosis, its signs and symptoms, possible complications, and treatment regimen.
- Patient will verbalize ways to prevent alkalosis.
Assessment:
1. Assess the health literacy of the patient.
Assessment of health literacy allows accurate care planning and ensures an appropriate teaching approach. Patients with poor health literacy often have poorer health outcomes.
2. Assess the patient’s motivation to learn.
Willingness and motivation to learn impacts health teaching outcomes. If the patient is not cognitively aware, direct teaching towards a support person.
Interventions:
1. Educate the patient about the signs and symptoms of metabolic alkalosis.
Metabolic alkalosis doesn’t always have obvious signs, and the patient may be unaware. The nurse can educate on potential causes and to monitor for changes in alertness, muscle control, or numbness and tingling in the extremities.
2. Discuss medication and alkali ingestion.
Patients who take diuretics are at a higher risk of experiencing metabolic alkalosis from electrolyte imbalances. Educate patients and families that antacids contain sodium bicarbonate, and baking soda is sodium bicarbonate. Excessive ingestion of these can result in metabolic alkalosis.
3. Discuss severe complications with patients with renal failure.
Renal failure prevents the body’s natural buffering system from correcting the acid-base balance. These patients may require dialysis and intense inpatient management.
4. Educate on sources of potassium and calcium.
Electrolytes can be lost with metabolic alkalosis. If the patient can tolerate PO consumption, have them eat dried fruits, potatoes, avocado, and bananas for potassium and cheese, almonds, salmon, and dairy for calcium.
References
- ACCN Essentials of Critical Care Nursing. 3rd Edition. Suzanne M. Burns, MSN, RRT, ACNP, CCRN, FAAN, FCCM, FAANP. 2014. McGraw Hill Education.
- Alkalosis. MedlinePlus. Reviewed: November 6, 2021. From: https://medlineplus.gov/ency/article/001183.htm
- Medical-Surgical Nursing: Concepts for Interprofessional Collaborative Care. 9th Edition. Donna D. Ignatavicius, MS, RN, CNE, ANEF. 2018. Elsevier, Inc.
- Metabolic Alkalosis. Journal of the American Society of Nephrology. February 11, 2000. From: https://jasn.asnjournals.org/content/11/2/369
- Physiology, Metabolic Alkalosis. Brinkman JE, Sharma S. [Updated 2022 Jul 18]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK482291/
