Figure 5.

Overplots of mean and 95% confidence intervals of extrapolated minute ventilation at PetCO₂ 55 mmHg (V_E55) vs. plasma morphine equivalents (morphine + 1.5x oxycodone concentrations) for each treatment. The values for “before” drug treatment (time = 0) are slightly staggered to show the values of V_E55 for drug concentration = 0.

Abbreviations: M15 = morphine 15 mg, M10/O5 = morphine mg + oxycodone 5 mg; M7.5/O7.5 = morphine 7.5 mg + oxycodone 7.5 mg; M5/O10 = morphine 5 mg + oxycodone 10 mg; O15 = oxycodone 15 mg. M15 (•); M10/O5 (▴); M7.5/O7.5 (▾); M5/O10 (▪); O15 (♦)