Blythe knew that Vader would be in some degree of pain, but she couldn't determine how much, because he said nothing. She expected he was keen enough that he would say something if it became unbearable. But then, he had ruled an Empire, and the average man was already difficult enough to deal with in the first place.
Still, this was not the time to mull over such things. In the midst of surgery, with this man's life literally in her hands, any distraction was deadly. She could feel his lungs between her fingers, the crisp tissues cleaning away under her touch. The tissues were regrowing, new, vital, healthy. Once she finished with the organ itself, she would recreate the tissues that the machines had replaced.
For a moment, Blythe felt her breath seize, the corset not helping much. She realized at the rate she was going, she would be very sick by the end of this. But she never wavered. "Nod to answer. If you speak, I could damage your lungs. But I only wish to inform you that your lungs are nearly completely healed. It will only take me approximately ten more minutes."