When administering nitrous oxide, monitoring of which vital sign is most critical?

Monitoring oxygen saturation is critical when administering nitrous oxide because it directly indicates the patient's oxygen levels and their respiratory function. Nitrous oxide can cause sedation and impact a person's ability to breathe effectively. If oxygen saturation levels drop, it may signify that the patient is not receiving adequate oxygen, potentially leading to hypoxia or respiratory distress.

Maintaining adequate oxygenation is paramount during procedures that involve nitrous oxide, as the sedative effects can alter the respiratory drive. In many cases, nitrous oxide is administered in conjunction with oxygen, and continuous monitoring ensures that the balance between sedation and sufficient oxygenation is maintained. If oxygen saturation falls below normal levels, it may be necessary to intervene and provide supplemental oxygen or adjust the nitrous oxide administration.

Other vital signs, such as heart rate, respiratory rate, and blood pressure, are certainly important and provide valuable information about a patient's hemodynamic stability and overall condition, but they do not offer the same immediate insight into the patient's respiratory status and potential hypoxemia as oxygen saturation does.