Which of the following indicates the appropriate breathing instructions for a transthoracic lateral humerus radiograph?

For a transthoracic lateral humerus radiograph, instructing the patient to breathe normally is appropriate because it helps ensure that the respiratory system's motion does not interfere with the imaging quality, specifically in regions where lung structures or other vital organs could obscure the humerus on the x-ray.

Normal breathing allows for consistent exposure times and minimizes potential motion artifacts that could occur with shallow or deep breathing techniques. Shallow breathing could lead to underexposure and affect the clarity of the humerus, while deep breaths may increase movement and create a similar risk of blurring the image. Requiring the patient to hold their breath is typically reserved for different types of imaging where motion must be completely eliminated, often in chest or abdominal views, and isn’t usually standard for an upper extremity radiograph.

Therefore, normal breathing is the ideal instruction, as it strikes a balance, allowing for sufficient exposure while maintaining stability for accurate imaging of the lateral humerus.