Blood tests for potassium and sodium identify ________.

Which of the following devices is considered to be the first electrically powered nega-tive-pressure ventilator?

a. The Bird b. The iron lung c. The chest cuirass d. The rocking bed

A ________ pacemaker is one where a lead wire is inserted through the skin and threaded into a large vein leading into the right side of the heart.

A. transcutaneous B. transvenous C. subcutaneous D. substernal