Figure 2.

Changes in physiological measures. Depicted are the changes across time in heart rate (a), respiratory volume over time (b), and end‐tidal CO₂, and the change in blood pressure between pre‐ and post‐drug, for placebo (red), ketamine (blue), and midazolam (green). Infusion started at time 0, and error bars/shading are the standard error of the mean. Only ketamine significantly modulated the first three parameters, with increases in HR (p < .001) and RVT (p = .04), and decreases in end‐tidal CO₂ (p = .003). Ketamine also significantly increased both systolic (p = .01) and diastolic (p = .002) blood pressure, while midazolam decreased these (systolic: p < .001, diastolic: p = .005)