Abstract Background: The use of anesthetic ketamine at usual doses has been limited by side effects such as sympathetic stimulation, treatment-emergent delirium, and prolonged recovery time. Recently, there has been a growing interest in combining subanesthetic doses of ketamine with subanesthetic doses of drugs such as propofol and dexmedetomidine to mitigate the unwanted effects of ketamine. Hence, we aimed to compare the effectiveness, in terms of postoperative Aldrete scores, intraoperative pain, sedation scores, hemodynamic changes, respiratory effects, surgeon satisfaction, and postoperative delirium, of continuous infusions of ketamine with adjuvant dexmedetomidine versus continuous infusions of ketamine with adjuvant propofol among patients undergoing elective upper limb surgery under brachial plexus block. Methods: We performed a double-blind, randomized, controlled trial among 60 participants randomly allocated into two groups. Group A patients (n = 30) received ketamine 0.5 mg/kg mixed with dexmedetomidine 0.5 μg/kg in 100 mL/h lipid emulsion as an infusion, whereas Group B patients received ketamine 0.5 mg/kg mixed with propofol 1 mg/kg in 100 mL/h normal saline as an infusion. Results: The mean Aldrete score at 0 min, 30 min, and 1 h was significantly higher among Group B patients (P = 0.001, P = 0.001, and P = 0.043, respectively). The mean diastolic blood pressure at 2 h was significantly higher in Group A compared to Group B (87.8 vs. 77.8, P = 0.001). Similarly, the mean arterial pressure at 45 min and 90 min was significantly higher in Group A compared to Group B (97.1 ± 6.7 vs. 92.2 ± 6.0, P = 0.004; 95.5 ± 5.5 vs. 90.8 ± 6.3, P = 0.005, respectively). The mean sedation score was not significantly different between groups. Conclusion: Propofol, when used as an adjuvant to ketamine, provides better hemodynamic stability and better Aldrete score in patients who receive brachial plexus block for elective upper limb surgeries compared to adjuvant dexmedetomidine.