A child diagnosed with strep throat 3 days ago enters the clinic crying hysterically. The parent tells the practical nurse (PN) that the child screams in pain even with a light touch. The child is short of breath and anxious. Which manifestations warrant immediate intervention by the PN?

A. A slightly raised rash with ragged edges might indicate a mild skin condition but isn't typically an immediate concern for intervention in this scenario. B. Red, hot, and swollen joints could indicate a serious condition like septic arthritis and would require immediate attention. C. While an elevated heart rate can be a concern, it might be expected in a distressed child and might not be as urgent as other symptoms in this case. D. A pulse oximetry reading of 88% O2 saturation indicates a significant decrease in oxygen levels and requires immediate intervention to ensure adequate oxygenation.