Driving Can Be Dangerous to Your Health by Phil Stephens
Part IV—Tests, Tests, and More Tests
John held his wife’s hand. The hip replacement surgery had worried her, but at least she understood what was going on. Tests using computers and X-rays were something else because she did not understand them. He smiled as he remembered how she would spend hours on the Internet doing research before surgery.
“I didn’t know that they could do another X-ray so soon after the ones I had for the surgery, but the technician said that it was necessary to rule out a lot of possibilities. Did you go on the Internet, as I asked you? What did you find out about the V/Q scan I had?” Barbara asked John.
“The Internet is a wonderful, thing, Barb. I think I may be your first convert,” said John as a fumbled in his pocket. He put on his glasses and read his notes on the folder paper.
“Did they get you to inhale a powder and take pictures, and then take more pictures after they injected something into your vein?” asked John.
“Yes. The technician said that they were radioactive tracers, but the radiation was at such low levels that it was not dangerous.”
“Well, that sounds right. This ventilation quantification scan, or V/Q scan as you called it, allows them to see air flow and blood flow through your lungs,” said John.
“They seemed to get the results quick enough, because then they took me for a spiral CT scan, which apparently takes a bunch of x-rays and then uses a computer to make a 3-dimensional picture of me! It’s really amazing what they can do these days.”
“What I don’t understand,” Barbara continued, “is why they scanned my legs with the CT and then did an ultrasound. I know my legs are swollen, perhaps a little worse than usual, but they always swell up after long car trips.”
John stood up and walked around the bed. He picked up the chart hanging on the bottom of the bed and glanced at the notes written when his wife was admitted.
| Test | Barbara | Normal |
|---|---|---|
| ECG | Normal (fast) | Normal |
| Heart rate (b/m) | 95 | 75 |
| Blood pressure | 90/58 | 110/65 |
| Arterial PO2 | 78 | 100 |
| Arterial PCO2 | 45 | 40 |
| Blood pH | 7.25 | 7.4 |
| Blood creatine phosphokinase-2 | 2.7 nanograms/mL | 3 nanograms/mL |
| Blood troponin-I | 1.9 micrograms/L | <3 micrograms/L |
| Breathing rate | 20; labored | 12 |
| Breathing sounds | Wheezing | — |
| Asthmatic | Yes | — |
Questions
- What do the ECG and the blood levels of creatine phosphokinase-2 and troponin-I tell you about the likelihood that Barbara had a heart attack?
- Why are Barbara’s arterial PO2, PCO2, and pH values different from normal?
- Are your ideas consistent with her blood pressure and heart rate?
- What conditions cause contraction of the bronchiole smooth muscle?
- What conditions cause contraction of the (pulmonary) arteriole smooth muscle?
- Why did the doctor ask for a CT scan and ultrasound of Barbara’s legs?
- With Barbara’s symptoms in mind, and the tests that were performed, do you wish to speculate about her condition?
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