ABSTRACT
UNLABELLED: Sevoflurane, an inhalational hypotensive anesthetic agent with a vasodilatory property, has been commonly used as a single agent to induce hypotension and effectively decrease blood loss in orthognathic surgery. However, it is common for patients to receive other hypotensive anesthetic agents in combination with sevoflurane. The purpose of our retrospective cohort study is to investigate whether administering an additional hypotensive agent has greater effect at reducing mean arterial pressure (MAP), estimated blood loss (EBL) and surgery time during orthognathic surgery. MATERIAL AND METHODS: 57 subjects, aged 0-89 of both genders, who underwent orthognathic surgery were investigated in this study. Each patient's anesthesia records were reviewed to record the following variables of interest: EBL, duration of surgery, and MAP reduction in %. 41 subjects were placed in Group I and they received sevoflurane alone. 16 subjects were placed in Group II and they received sevoflurane plus a "supportive" agent. These "supportive" agents were esmolol, labetalol, metoprolol, nicardipine, and dexmedetomidine. The significant differences between two groups were assessed by using ANCOVA and p < 0.05 was regarded as significant. Wilcoxon signed-rank test was used to look for differences in surgery time. RESULTS: Subjects in Group II experienced a greater reduction in MAP during surgery than subjects in Group I, 27.30% and 20.44%, respectively (p = 0.027). There was no significant difference for sex (p = 0.417) or age group (p = 0.113) in estimated blood loss, however. The mean surgery time in Group I was 1.93, 2.77, and 4.54 h with respect to LeFort, BSSO/IVRO, and double jaw surgery. Patients in Group II had a mean surgery time of 1.73, 2.07, and 5.64 h with respect to LeFort, BSSO/IVRO, and double jaw surgery. No statistically significant difference was demonstrated in surgery time between Group I vs. Group II (p > 0.05). Subjects in Group II experienced, on average, more blood loss than subjects in Group I, 355.50 ml and 238.90 ml, respectively. CONCLUSION: The use of multi-drug combination may offer significant advantage of reducing patients' mean arterial pressure. However, this has no significant effect on reducing blood loss or surgery time in comparison to sevoflurane alone.
