Background
Controlled hypotension is a technique that is used to limit intraoperative blood loss, improve operative field, decrease duration of surgery, and thus decrease the amount of blood transfused.
Objective
The aim of this double-blind, randomized, controlled study is to compare the effects of sevoflurane combined with dexmedetomidine (DEX) or nimodipine (NIMO) on blood loss in the surgical field, recovery time, and patient tolerability in spine surgery.
Methods
Forty-eight (48) patients, 20–50 years of age, ASA I-II, randomly divided into DEX group ( = 24) and NIMO group ( = 24). In the DEX group, a loading dose of DEX infused over 10 min at a rate of 1 μg/kg/h, followed by a maintenance rate of 0.4–0.8 μg/kg/h. In the NIMO group, the dose infused at 15 μg/kg/h for 2 h (approximately 1 mg/h). The infusion rates were titrated to maintain mean arterial pressure (MAP) of 60–65 mm. Hg. We recorded MAP, intraoperative blood loss, total recovery time, total fentanyl consumption, incidence of arrhythmia or ischemia, and postoperative nausea and vomiting.
Results
No significant difference in the amount of blood loss between the two groups was observed. Total fentanyl consumption was significantly higher in the NIMO group (350 ± 8.9 μg) versus (200 ± 5.5 μg) in the DEX group ( = 0.002). Recovery time was shorter in the NIMO group (6.8 min) versus (8.9 min) in the DEX group ( = 0.001).
Conclusions
Dexmedetomidine and Nimodipine provided effective method of controlled hypotension limiting the blood loss, and NIMO was associated with significantly shorter extubation and recovery times compared with DEX.