Clinical Scenario 1:
L.A. and her husband are doing yard work on a hot and humid day. L.A. spends ~3 hours outside and is exposed to direct sunlight, sweating profusely in an attempt to cool herself. She begins to feel disoriented and weak and when she summons her husband for help she ends up collapsing. She wakes up in the emergency department hooked up to an IV.

1.3 What is the composition of the fluid remaining in the body compartment affected?

Clinical Scenario 2:
B.D. is in a vehicular accident and suffers significant trauma, including a sizeable laceration to his leg. He is bleeding when the emergency responders arrive and continues bleeding during transport to the emergency room.

2.3 What is the composition of the fluid remaining in the body compartment affected?

Clinical Scenario 3:
G.R. is running a marathon (26.2 miles) for a local charity on a warm day. Thankfully, the course organizers have set up aid stations at every mile of the run, offering up ice-cold water. G.R. takes a few cups at each station and, by mile 18, is feeling bloated and disorientated. She stumbles to the side of the course and collapses. G.R. wakes up in the emergency department hooked up to an IV.

3.4 Justify an IV fluid treatment most appropriate for the scenario. Support with your understanding of physiology and cell volume regulation.

CASE II
Meg Newton is a 32 year old assistant at a veterinary clinic. She feeds, grooms, and exercises the animals housed for prolonged stays. At age 27, she had an episode of blurred vision and was having trouble reading the newspaper and the fine print on labels. Concerned, she made an appointment with an optometrist, but when her vision cleared on its own, she was relieved and canceled the appointment. Ten months later the blurred vision returned, this time with other symptoms that could not be ignored. She had double vision and a ‘pins and needles’ feeling with severe weakness in her legs. She was even too weak to perform her routine activities at work.

Meg was referred to a neurologist, who ordered a series of test. MRI of the brain showed lesions typical of multiple sclerosis. Visual-evoked potentials had a prolonged latency that was consistent with decreased nerve conduction. Since the diagnosis, Meg has had two relapses, and she is currently being treated with interferon beta.

3. Is the axial/intracellular resistance of Meg’s axon changing? Why or why not? How do you change an axial/intracellular resistance and can that be achieved under normal circumstances?

5. What is occurring at the nodes of Ranvier distal to the stimulus in multiple sclerosis? What has occurred to saltatory conduction in this patient and why?

Clinical Scenario 1: L.A. and her husband are doing yard work on a...