From the FDA Drug Label
In cardiac arrest, a rapid intravenous dose of one to two 50 mL vials (44.6 to 100 mEq) may be given initially and continued at a rate of 50 mL (44. 6 to 50 mEq) every 5 to 10 minutes if necessary (as indicated by arterial pH and blood gas monitoring) to reverse the acidosis. In metabolic acidosis associated with shock, therapy should be monitored by measuring blood gases, plasma osmolarity, arterial blood lactate, hemodynamics and cardiac rhythm.
The acid-base imbalance with a pH of 7.53, low carbon dioxide (pCO2) levels of 17, low bicarbonate (HCO3) levels of 17, and a base excess of -6 is characterized as a metabolic acidosis with a respiratory alkalosis component, given the low pCO2 levels.
- The low bicarbonate level and negative base excess indicate a metabolic acidosis.
- The low pCO2 level suggests a respiratory alkalosis. This mixed disorder is likely due to a primary metabolic acidosis with a compensatory respiratory alkalosis 1.
From the Research
This acid-base imbalance represents respiratory alkalosis with partial metabolic compensation, as indicated by the elevated pH of 7.53, low pCO2, low bicarbonate level, and negative base excess of -6, according to the most recent and highest quality study 2. The elevated pH of 7.53 indicates alkalemia, while the low pCO2 points to respiratory alkalosis as the primary disturbance.
- The low bicarbonate level and negative base excess of -6 reflect the kidneys' compensatory response, attempting to normalize pH by decreasing bicarbonate retention.
- Respiratory alkalosis occurs when hyperventilation leads to excessive carbon dioxide elimination from the lungs, which can be caused by anxiety, high altitude, early sepsis, pulmonary disorders, or central nervous system stimulation, as discussed in 3 and 2.
- The body attempts to compensate by decreasing renal bicarbonate reabsorption, but this compensation is only partial, as evidenced by the still-elevated pH. This condition requires identifying and treating the underlying cause of hyperventilation rather than directly addressing the alkalosis.
- If the patient is symptomatic, they may experience lightheadedness, paresthesias, or carpopedal spasms. Management focuses on treating the primary cause while monitoring electrolytes and acid-base status until resolution, as emphasized in 3 and 2.