Perfusion Index and Hemodynamic Responses During Propofol Induction with Fentanyl or Ketamine–Lidocaine Adjuncts: A Prospective Randomized Pilot Clinical Study

Background and Objectives: Hemodynamic instability during anesthesia induction and endotracheal intubation remains a clinically important concern. Low-dose ketamine and intravenous lidocaine may provide complementary effects that improve cardiovascular stability and peripheral perfusion. This pilot study evaluated effects of adding ketamine and lidocaine to a propofol-based induction regimen using mean arterial pressure (MAP) and perfusion index (PI) as monitoring parameters. Materials and Methods: In this prospective observational pilot study, 30 adult patients undergoing elective surgery requiring general anesthesia and endotracheal intubation were allocated to either a standard induction regimen (Group 1: propofol 2 mg/kg and fentanyl 2 μg/kg) or an adjunctive regimen (Group 2: propofol 2 mg/kg, ketamine 0.4 mg/kg, lidocaine 1 mg/kg, and fentanyl 1 μg/kg). Hemodynamic variables and PI were recorded at baseline, after induction, and after intubation. Postoperative sore throat and cough-reflex responses were also assessed. Results: No significant differences between-groups were observed in heart rate, systolic blood pressure, diastolic blood pressure, MAP, or oxygen saturation at any time point. However, MAP decreased significantly within Group 1 after induction (94.9 ± 10.1 vs. 76.9 ± 13.8 mmHg, p < 0.001) and remained lower after intubation (p = 0.001), whereas no significant MAP changes occurred within Group 2. PI increased in both groups but was significantly higher in Group 2 after induction (5.35 ± 2.34 vs. 3.46 ± 2.90, p = 0.043) and after intubation (7.02 ± 2.89 vs. 4.71 ± 2.22, p = 0.020). Postoperative sore throat scores were lower in Group 2 (0.53 ± 0.91 vs. 1.67 ± 1.76, p = 0.035), and cough-reflex scores were also reduced (p = 0.024). Conclusions: The addition of low-dose ketamine and intravenous lidocaine to propofol-based induction was associated with higher perfusion index values and reduced airway-related adverse effects. No statistically significant between-group difference in mean arterial pressure (MAP) was detected. These findings are hypothesis-generating and warrant confirmation in larger randomized trials.