Sodium bicarbonate injected into a blood vessel transforms to carbon dioxide and water. The increase in carbon dioxide production can be detected by measuring the exhaled carbon dioxide in the lungs.

This study is conducted to access the clinical application of measuring exhaled carbon dioxide to verify the correct position of intravenous catheters.Once the catheter is in the correct position the injected bicarbonate will be detected as a distinct elevation of exhaled carbon dioxide. A similar study was already performed in adults and was found useful. The investigators now extend the clinical application to children.

Extravasation is the unintentional injection or leakage of fluids into the perivascular or subcutaneous space resulting in potential tissue injury. This prospective controlled study, will assesse the diagnostic utility of using intravenous diluted sodium bicarbonate to confirm placement of intravenous (IV) catheters in ventilated children. Diluted sodium bicarbonate will be created using undiluted standard 8.4% (1 meq/mL) sodium bicarbonate mixed in a 1:3 ratio with sterile water to achieve a final diluted concentration of 2.1% (0.25 mEq/mL). In 20 ASA I-II mechanically ventilated children age 2-8 years, the effects of 1 ml/kg of diluted 2.1% sodium bicarbonate or 0.9% normal saline,injected in a randomized order, will be analyzed. All children will have venous blood samples taken prior to injection and 10 minutes after injection for analysis of venous blood pH and electrolytes.

Inclusion Criteria:

• ASA I,II
• age 2-8 years

Exclusion Criteria:

• ASA III or higher