Respiratory Alkalosis in Pediatrics
Respiratory Alkalosis in Pediatrics
Respiratory alkalosis is a condition wherein the body’s carbon dioxide level is low. Frequently, pain, anxiety, infection (gram negative septicaemia / bacteremia), meningitis, mechanical overventilation, hypoxemia, salicylate poisoning or intoxication, inappropriate ventilator setting and other conditions that cause the child to hyperventilate (blows off too much CO2 – causing a decrease in the plasma carbonic acid concentration) leads to respiratory alkalosis. Chronic respiratory alkalosis on the other hand results from chronic hypocapnia, chronic renal insufficiency and cerebral tumors. It is a condition where arterial pH is greater than 7.45 and the PaCO2 is less than 38 mm Hg. The child will eventually manifest numbness, faintness, tingling sensation on proximal extremities, light headedness and confusion.
Causes
The following is a summary of the predisposing factors of respiratory alkalosis:
- Alveolar hyperventilation
- Decreased pCO2 levels
- Overzealous mechanical ventilation
- Anxiety
- Heart failure
- Sepsis
- Hepatic failure
- Fever
- Hypermetabolic states
- Salicylate poisoning
Manifestations
The following are some of the presentations that may be present in a child with respiratory alkasis:
- Tachypnea
- Diaphoresis
- Numbness
- Tingling of toes
- Tingling of fingers
- Syncope
- Dizziness
- Light headedness (from vasoconstriction and decreased cerebral blood flow)
- Inability to concentrate
- Tinnitus
- Loss of consciousness
- Tachycardia
- Atrial dysrhythmias
Assessment and Diagnosis
The following assessment and diagnostic tool verifies the presence of respiratory alkalosis:
- Arterial blood gas studies
- The pH is above normal levels
- Low PaCO2
- Normal bicarbonate level
- Serum electrolyte studies
- Decrease in serum potassium (hydrogen is pulled out of the cells in exchange for potassium)
- Decrease in serum calcium (severe alkalosis reduces calcium ionization)
- Decrease in serum phosphate (in alkalosis, cells take up increased number of phosphates)
- Toxicology Screen – used to rule out salicylate poisoning or intoxication
Management
- To manage respiratory alkalosis, the health team needs to treat the underlying cause.
- If the child is in an anxious stage, he is instructed to breathe slowly in order for the carbon dioxide to accumulate. The child is also taught to breathe in a closed system (through a paper bag) to preserve the carbon dioxide inhaled.
- For the child’s hyperventilation, a prescribed sedative may be given as ordered. This relieves the anxiety and the over ventilation and thus decrease the acidosis.
- Administer sodium NaCl and KCl as ordered.
- Fluid volume replacement is initiated as indicted.
- Seizure precautions should be observed.
- Child’s intake and output monitoring is strictly observed.
- Electrolyte level is monitored.
Byron Webb Romero, RN, MSN
Finished BSN at Lyceum of the Philippines University, and Master of Science in Nursing Major in Adult Health Nursing at the University of the East Ramon Magsaysay Memorial Medical Center. Currently working at Manila Doctors College of Nursing as a Team Leader for Level I and II, Lecturer for Professional Nursing Subjects, and also a Clinical Instructor.
