Fig. 4

Changes of ΔP (A) and ΔHR (B) before and after the induction of general anesthesia and intubation in groups. Values were expressed as median and interquartile range. ΔP and ΔHR were analyzed with Kruskal–Wallis test. *P < 0.05 vs. Group C. Abbreviations: ΔP: Degree of change in MBP at each time course from baseline [ΔP=(P-PBaseline)/ PBaseline]. ΔHR: Degree of change in HR at each time course from baseline [ΔHR=(HR-HRBaseline)/ HRBaseline]. Inb = before induction; Int = immediately after intubation; T1 = 1 min after intubation; T5 = 5 min after intubation. Group C (control): injected with normal saline. Group K0.1: injected with 0.1 mg/kg esketamine. Group K0.3: injected with 0.3 mg/kg esketamine. Group K0.5: injected with 0.5 mg/kg esketamine