A patient presents with acute shortness of breath and pale skin. What is your best immediate step?

In a scenario where a patient presents with acute shortness of breath and pale skin, administering high-flow oxygen and assessing breathing adequacy is the most appropriate immediate step. High-flow oxygen can help ensure that the patient receives sufficient oxygen to mitigate the effects of hypoxia, especially since acute shortness of breath indicates a potential respiratory issue.

Assessing the adequacy of breathing is crucial as it allows you to evaluate whether the patient can maintain their own ventilation or requires assistance. This dual approach ensures that immediate oxygenation is provided while you gather vital information about their respiratory status.

Other options may not address the situation as effectively. For instance, placing the patient supine and ventilating with a bag-mask device could be appropriate in a different context but would not be the best initial action without first determining the adequacy of spontaneous breathing. Delivering humidified oxygen and administering an inhaled bronchodilator may be beneficial in cases of wheezing or chronic obstructive pulmonary disease but would potentially delay the necessary immediate intervention of oxygenation. Giving supplemental oxygen only if saturation is under 90% is not proactive enough in an emergency setting where acute symptoms are present, as the patient may already be in distress before reaching that threshold.