Part I—The Accident

Suzie Jones felt her heart pounding and the sweat dripping from her forehead as she ran the last mile through her neighborhood. She had left home at noon and had run around the high school track for what seemed like hours. She felt tired when she started, but found it pleasurable to drive her body to a point of exhaustion, believing that she could run forever on that warm spring afternoon. As a child, she had hated exercising, but now she found it helped clear her head and get her thoughts into perspective. Suzie felt light-headed as she rounded the corner for home.

“Funny,” she thought. “Where’s Mom’s car?”

She saw a note taped to the garage door.

David’s had an accident, come to the hospital ASAP.

“This time next year I’ll be able to drive,” muttered Suzie as she started to run the mile to the hospital.

Suzie entered the Emergency Room and saw her mother sitting with her brother Dave’s baseball coach.

“What happened?” asked Suzie.

Mrs. Jones looked at the coach and he answered: “A freak accident. Dave rolled his ankle as he was rounding first base. He hit the ground and we all thought that his leg was broken, but the x-rays proved us wrong. It’s just a badly sprained ankle.”

Suzie nodded her head in response as she walked the short distance to the water fountain. Just then, Mrs. Jones noticed one of the nurses and said to Suzie, “Isn’t that your friend’s sister at the nurse’s station? Why don’t you ask her how your brother is and how much longer this will take?”

“Mom, I’ve been running for hours and I smell. I look a mess. If it hadn’t been for your note telling me to come right away, I would have showered and changed before coming here.”

“Fine, Susan. We’ll just wait then,” replied Mrs. Jones, making her daughter feel guilty.

After about 10 minutes, a nurse called Mrs. Jones into the examination room, and after another 15 minutes she appeared with Dave, who was sitting in a wheel chair, awkwardly holding crutches. Suzie and the coach rose to meet them.

“I’ve given you a prescription for a more powerful analgesic than your regular over-the-counter pain medicine,” said the doctor. Mrs. Jones held up the piece of paper and smiled at the young intern.

“Inflammation is caused by fluid moving from the blood and accumulating in the space between the cells. To minimize the inflammation of Dave’s ankle, just remember PRICE—Protect, Rest, Ice, Compression, and Elevation. Call your family physician if his pain becomes severe,” said the young doctor as he walked back to the examination rooms.

Questions

1. What two parameters are responsible for creating the movement (filtration and reabsorption) of fluid across the capillary wall?
2. Draw a diagram of a capillary and label arteriole at one end and venule at the other. With pressure on the vertical axis, draw two lines to show how the two parameters (see question 1 above) vary along the length of the capillary.
3. Under normal circumstances, what components of the blood cross the capillary wall?
4. Cytokines, like histamine and leukotrienes, are secreted by damaged cells in Dave’s ankle. How do these cytokines cause inflammation?
5. How does the application of ice to the ankle affect blood flow through the capillaries?
6. How does the removal of ice from the ankle affect blood flow through the capillaries and the cytokines?
7. How does compression, which is provided by an elastic (Ace) bandage wrapped around the damaged ankle, decrease inflammation?
8. How does elevation of the damaged ankle decrease inflammation?

Date Posted: 03/18/07.

Image Credit: Photograph © scarpi/FOTOLIA.

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