Related Experiment Videos
Hypokalemia induced by inhaled bronchodilators
D M Gelmont1, J R Balmes, A Yee
1Barlow Hospital for Respiratory Diseases, Los Angeles.
Chest
|October 1, 1988
Summary
Inhaled beta 2-adrenergic agonists, like metaproterenol, can significantly lower potassium levels in patients on mechanical ventilation. This study investigated the hypokalemic effects of inhaled bronchodilators.
Area of Science:
- Pulmonary Medicine
- Pharmacology
- Critical Care
Background:
- Parenteral administration of beta 2-adrenergic agonists is known to cause hypokalemia.
- The potential for inhaled beta 2-agonists to induce similar effects in patients receiving mechanical ventilation requires investigation.
Purpose of the Study:
- To determine if inhaled beta 2-adrenergic agonists, commonly used as bronchodilators, can induce hypokalemia in mechanically ventilated patients.
- To compare the potassium-lowering effects of metaproterenol and isoetharine with atropine.
Main Methods:
- Six subjects on assisted mechanical ventilation received nebulized metaproterenol, isoetharine, or atropine in a randomized order.
- Plasma potassium levels were measured every 5 minutes for 50 minutes post-administration.
- Arterial blood gases were monitored at 15-minute intervals.
Main Results:
- All tested bronchodilators, including metaproterenol and atropine, caused a decline in plasma potassium.
- Metaproterenol and atropine showed a statistically significant decrease in plasma potassium (p=0.04 and p=0.001, respectively).
- Metaproterenol induced the largest average decline in plasma potassium (-0.6 mEq/L).
Conclusions:
- Inhaled beta 2-adrenergic agonists, particularly metaproterenol, can lead to hypokalemia in mechanically ventilated patients.
- Clinicians should monitor potassium levels when administering these inhaled bronchodilators to this patient population.