Ace the Rosh Pediatrics Practice Exam 2025 – Bring Your A-Game to the Future of Care!

In the context of this 17-year-old girl presenting with sore throat, subjective fever, and fatigue, a heart rate of 105 beats per minute indicates tachycardia. Tachycardia is generally defined as a resting heart rate elevated above the normal range, which is typically considered to be greater than 100 beats per minute in adults and older children.

Understanding this vital sign is essential, as it reflects the body’s response to factors such as infection, pain, or stress. In this case, the girl's presentation raises suspicion for an infectious process, which could lead to increased cardiac output and, consequently, a faster heart rate.

Blood pressure, respiratory rate, and body temperature provide important clinical information but do not directly indicate tachycardia. A blood pressure of 120/80 mm Hg is within normal limits and does not suggest tachycardia. A respiratory rate of 20 breaths per minute falls within the normal range for adolescents, and while a body temperature of 101.6°F indicates fever, it does not specifically address heart rate. Therefore, the heart rate of 105 bpm is the clear indicator of tachycardia in this patient.