| 
      
        |  | Group A(n=20) | Group E (n=20) | Group N (n=20) | p value |  
        | Mephentermine used | 1 (5%) | 1 (5%) | 12 (60%) | 0.01* |  
        | Bradycardia | 0 | 0 | 8 (40%) | 0.01* |  
        | Tachycardia | 1 (5%) | 0 (0%) | 0 (0%) | 0.48 |  
        | Other adverse effects | 0 | 0 | 0 |  |  
        | Data described as number (percentage); *p<0.05    considered statistically significant. |  |