Does premedication with dexmedetomidine provide perioperative hemodynamic stability in hypertensive patients?

Perioperative hemodynamic fluctuations are seen more often in hypertensive patients than in normotensive patients. The purpose of our study was to investigate the perioperative hemodynamic effects of dexmedetomidine and midazolam used for premedication in hypertensive patients relative to each other and in comparison to normotensive patients.

One-hundred-forty female, normotensive or hypertensive patients undergoing myomectomies or hysterectomies. They were randomly enrolled into the subgroups: Group ND (normotensive-dexmedetomidine); Group HD (hypertensive-dexmedetomine); Group NM (normotensive-midazolam); Group HM (hypertensive- midazolam). Dexmedetomidine was administered at a concentration of 0.5 μg.kg⁻¹, and midazolam was administered at a concentration of 0.025 μg.kg⁻¹ via intravenous (IV) infusion before the induction of anaesthesia. Haemodynamic parameters were recorded at several times (T_beginning, T_{preop5 min}, T_{preop 10 min}, T_induction, T_intubation, T_{intubation 5 min}, T_{initial surgery}, T_{surgery 15 min}, T_{surgery 30 min}, T_extubation, T_{extubation 5 min}). Propofol amount for induction, time between induction and initial surgery, demand of antihypertensive therapy, rescue atropine were recorded. Quantitative clinical and demographic characteristics were compared using One Way ANOVA. The values were compared using One-way Analysis of Variance. Additionally periodic variations were examined by One way Repeated Measures Analysis of Variance for groups separately.

SBP was significantly different between normotensive and hypertensive groups at the following time points: T_{preop 5 min}, T_{preop 10 min}, T_induction, T_intubation , T_{intubation 5 min} and T_{initial surgery}. MBP was significantly different in the hypertensive groups at T_induction, T_intubation, T_{intubation 5 min,} T_{initial surgery}, T_{surgery 15 min}, T_{surgery 30 min,} T_extubation and T_{extubation 5 min}. The perioperative requirements for antihypertensive drugs were significantly higher in Group HM.

In the hypertensive patients, dexmedetomidine premedication provides better hemodynamic stability compared with midazolam, and because it decreases the antihypertensive requirements, its use might be beneficial.

Trial registration: Clinicaltrials.gov identifier: NCT02058485.