For patients on oxygen therapy with no prior information, what is the initial FiO2 setting recommended?

The initial recommended FiO2 setting for patients on oxygen therapy, especially when there is no prior information available, is typically in the range of 40–60%. This level is often chosen as it provides sufficient oxygenation to address potential hypoxemia without overwhelming the patient with excessive oxygen, which could lead to complications such as oxygen toxicity or absorption atelectasis.

Setting the FiO2 at 40–60% is particularly useful in a clinical setting where the patient's oxygenation status is unknown, as it strikes a balance between offering adequate support while allowing for further assessment and adjustments based on the patient’s response. Once the patient's clinical status is better understood, and following arterial blood gas analysis or pulse oximetry, the healthcare provider can then tailor the oxygen therapy more specifically.

The other options, while they represent potential FiO2 settings, are either too low or potentially too high for initial settings in an acute situation where the patient’s condition is not yet fully understood. Starting with a moderate concentration allows for safe and effective initial management of their respiratory needs.