Alex Jacoby is 18 years old and a senior in high school. He comes to the office complaining of severe pain in his left shoulder. His vital signs are as follows: temperature 98.5\deg F, pulse 48 beats/ min, respirations 12 breaths/min, and blood pressure 108/68 mm Hg. Alex is an outstanding competitive swimmer and is currently ranked first in the state in the 100-yard butterfly. Alex has an important swim meet coming up and must do well so that he can get a college athletic scholarship. He says he thinks he can take 2 s off his best time at this meet and he doesn't want anything to interfere with that. Alex wants the physician to do whatever he can to make his shoulder better and thinks that a steroid injection and pain pills might be the answer. Alex also wants to know why his pulse rate is so slow.