Fig. 1

Relation of a heart rate (r² = 0.031, p = 0.04), b respiratory rate (r² = 0.001, p = 0.68), c episodes of apnea (r² < 0.001, p = 0.97) recorded during the physical exam in the day of TDM as a function of caffeine serum concentration. Note: b · min⁻¹, beats per minute; br · min⁻¹, breaths per minute