You are with a group of hikers on the third day of an 11,000-foot mountain ascent. One of the hikers has not been feeling well for a couple of days. Today, members of the group notice that he is having difficulty getting dressed and speaking. From your training in outdoor emergency care, you recognize that these signs and symptoms are most often associated with:

Which one of the following actions indicates that the EMT is correctly using a nonrebreather face mask on an adult patient?

A) He ensures that the reservoir fully collapses with each breath. B) He instructs the patient to take deeper breaths when the mask is on. C) He sets the oxygen flow rate to between 6 and 16 liters per minute. D) He fully inflates the reservoir prior to placing it on the patient.

Which of the following will impair cardiac output?

A) Improperly functioning valves B) Increased perfusion to the heart C) Elevated blood pressure D) Increase in mean arterial pressure