Effect of nitroglycerine versus phentolamine on P300 latency and amplitude
groups,*P-value ≤
The values of P300 latency showed a significant delay one week following surgery in both Nitroglycerine and Phentolamine groups (P-value ≤ 0.001, 0.001), but in Nitroglycerine group, the delay is significantly higher than in Phentolamine group (P-value = 0.003). The values of P300 amplitude significantly decreased one week following surgery in both Nitroglycerine and Phentolamine groups (P-value ≤ 0.001, 0.001). There was no statistically significant difference between Nitroglycerine and Phentolamine groups in the postoperative decrease in P300 amplitude (P-value = 0.099) (Table 
Pre and post-operative P300 latency and amplitude, in patients in Nitroglycerine and Phentolamine groupsValues are expressed as median (Q1-Q3)Wilcoxon test was used for comparison between pre and post-operative quantitative variables, Mixed ANOVA test was used for comparing pre and post-operative quantitative variables in the two groups,*P-value ≤ 0.05 is considered significantThe percent of change in P300 latency was significantly higher in Nitroglycerine group in comparison to Phentolamine group (P-value ≤ 0.001), but there was no statistically significant difference between Nitroglycerine and Phentolamine groups in the percent of change in P300 amplitude (P-value = 0.482) (Table 
Percent of change in P300 latency and amplitude in both Nitroglycerine and Phentolamine groupsValues are expressed as median (Q1-Q3)Mann-Whitney test was used for comparison between Nitroglycerine and Phentolamine groups*P-value ≤ 0.05 is considered significant