Vascular access in patients carries a significant risk of accidental extravasation of intravenous (IV) fluids and medications with the potential for tissue injury. This prospective controlled study assessed the diagnostic utility of using intravenous diluted sodium bicarbonate to confirm placement of IV catheters in volunteers . Diluted sodium bicarbonate or 0.9% normal saline, will be injected in a randomized order while end-tidal carbon dioxide in the exhaled air will be monitored. The investigators hypothesize that the injected bicarbonate will dissolve into carbon dioxide and water and cause a transient increase in the measured exhaled CO2. Arbitrary increase of more than 10%in end-tidal carbon dioxide is considered as a positive response.