Prism 5 for windows

In all experiments, a sample size of 5–10 animals was utilized. All data are presented as mean ± SEM. To compare differences between groups, one-way ANOVA was performed with Newman-Keuls test as post hoc. In some instances, behavioural data were analysed using two-way ANOVA followed by Bonferroni's test as post hoc. GraphPad Prism for Windows 5 (GraphPad Software, San Diego, CA, USA) was used for all statistical analysis. P < 0.05 (Newman-Keuls test or Bonferroni's test) was considered statistically significant.

A sample size of eight animals was used in all tests. All data are presented as mean ± standard error of the mean (SEM). To compare differences between groups, one-way analysis of variance (ANOVA) was performed with Newman-Keuls test as post hoc. Two‑way ANOVA with Bonferroni’s post hoc test (treatment × dose) was also performed to compare the NS and CMS groups. Time-course curves were subjected to two-way (treatment × time) repeated measures ANOVA with Bonferroni’s post hoc test. All statistical evaluations were performed using GraphPad Prism for Windows 5 (GraphPad Software, San Diego, CA, USA). Bonferroni’s test or Newman-Keuls test of P values < 0.05 were regarded as statistically significant.

GraphPad Prism for Windows 5.0 (GraphPad Software, Inc., San Diego, USA) was used for nonlinear regression to build dose-response of ΔBF. The equation of nonlinear regression is: $$Y=\mathit{\text{Bottom}}+\frac{\left(\mathit{Top}-\mathit{\text{Bottom}}\right)}{1+{10}^{\left(log{\mathit{EC}}_F-X\right)\times \mathit{\text{HillSlope}}}}$$
Where X is the logarithm of concentration of ropivacaine, Y is the relative blow flow ΔBF, F is a constant value between 0 and 100, Top is the Y value at the top plateau, Bottom is the Y value at the bottom plateau, is the X value when the response is halfway between Bottom and Top and HillSlope is the steepness of the curve.
Personal information, surgical details, MAP, HR, hemodynamics and T_s were collected and the data were presented as mean (SD) or numbers as appropriate. Paired-Samples T test was applied to compare hemodynamic parameters and skin temperature before and after brachial plexus block, Kruskal-Wallis H non-parametric test was applied to compare these variables among different concentration groups. Analysis of variance trend test and Jonckheere’s trend test were performed to detect the trend in changes of hemodynamic parameters and skin temperature as the concentration increased. Probit regression was used to calculate the ED₅₀ and ED₉₅ of ropivacaine on sensory block. For all tests, significance was defined as a p value <0.05. Statistical analysis was conducted using SPSS for Windows 16.0 (SPSS Inc., Chicago, USA).