Dexmedetomidine Premedication Increases Preoperative Sedation and Inhibits Stress Induced by Tracheal Intubation in Adult

A Prospective Randomized Double-blind Clinical Study

Jun Xiong; Jie Gao; Yanan Pang; Yafen Zhou; Yongxing Sun; Yanyan Sun


BMC Anesthesiol. 2022;22(398) 

In This Article

Abstract and Introduction


Objective: The aim of this prospective randomized double-blind study is to evaluate whether oral dexmedetomidine (DEX) premedication could increase sedation in order to reduce preoperative anxiety and inhibit stress response during general anesthesia tracheal intubation.

Materials: A total of 100 ASA I and II adult patients undergoing elective neurosurgery were randomly divided into the control group (C group, n = 50) and the oral DEX premedication (DEX group, n = 50). Patients were administrated 4 μg/kg dexmedetomidine orally pre-anesthesia 120 min. Hemodynamic variables were monitored and recorded from premedication to 10 min after tracheal intubation. The primary outcome, the sedation level of all participants, was evaluated by Richmond Agitation Sedation Scale (RASS), and Numerical Rating Scale was to measure their intensity of thirst and satisfaction of patients' family members. During general anesthesia induction, the total dosage of induction anesthetics and complications relative to anesthesia induction were recorded. After tracheal intubation, blood sample was drain from radial atrial line to measure levels of adrenocorticotropic hormone (ACTH) and cortisol.

Results: RASS scores at 60 min after premedication and on arrival in the operating room were significantly reduced in the DEX group (P < 0.001). Oral DEX premedication not only increased the intensity of thirst but also the satisfaction of their family members (P < 0.001). The cortisol level after tracheal intubation was deduced by oral DEX premedication (P < 0.05). Oral DEX premedication reduced heart rate (HR) and mean arterial pressure (MAP) on arrival in the operating room, and HR when tracheal intubation (P < 0.05). During the whole process of anesthesia induction, although the lowest MAP in two groups were not significantly different, the lowest HR was significantly lower in the DEX group (P < 0.05). Oral DEX premedication might reduce HR from premedication to 10 min after tracheal intubation. However MAP was reduced just from premedication to on arrival in the operating room. Total induction dosages of propofol, midazolam, sulfentanil and rocuronium were similar in two groups (P > 0.05), as well as the complications relative to anesthesia induction and cases of rescue dopamine therapy were similar (P > 0.05).

Conclusion: Oral DEX 4 μg/kg premedication was an efficient intervention to increase preoperative sedation and reduce stress reaction induced by general anesthesia tracheal intubation, but also it was with the stable hemodynamic during the process of general anesthesia tracheal intubation, and improved the satisfaction of patients' family members. In this study, the sparing-anesthetic effect of 4 μg/kg DEX oral premedication was not significant, and this would be needed to study in future.

Trial Registration: This trail was registered at Chinese Clinical Trial Registry (, Jie Gao) on 15/04/2021, registration number was ChiCTR2100045458.


The preoperative time is expected to be a stressful period for the majority of patients and their family members. Preoperative or pre-anesthesia anxiety is a huge impact on patients' emotion and psychiatry, which produces physical problems correlated with autonomic fluctuation and incidence of nausea and vomiting, as well as postoperative pain. This stress also affects potentially anesthesia, for example increasing requirement of anesthetic.[1] If not be relieved, it could be detrimental to postoperative outcomes. Therefore, it stands to reason that adequate relief of preoperative anxiety translates into better perioperative outcomes.[2]

To manage preoperative anxiety with premedication might demonstrate some effects against peri-operative anxiety, pain and other discomfort for surgeon and anesthesiologist to improve quality of anesthesia and surgical recovery.[3] Various medicines have been used preemptively to ameliorate preoperative discomfort and reduce side-effects of anesthetic,[4] including midazolam, opioids, atropine, and so on. Opioids are the most usually used premedication,[5] however which have to do with respiratory depression, nausea, and urinary retention. Midazolam, a benzodiazepine anxiolytic, is common for patients to experience preoperative anxiety because adequate sedation might ameliorate anxiety,[6] which with not only rapid onset of action and a minimum hemodynamic effect, but also muscle relaxant properties.[7] However the most adverse effects secondary to midazolam include respiratory depression and postoperative cognitive changes.[8] Additionally, although sedative premedication is widely used to improve patients' own experience, there is little clinical evidence to support sedative premedication or routine sedative premedication was demonstrated to be benefit in general anesthesia.[9] Hence consistent relieve of preoperative anxiety is still a major challenge, and there is a need for an ideal method which provides better preoperative stress relief with minimal side effects.[10]

Dexmedetomidine (DEX) is a highly selective agonist activating pre- and postsynaptic α2 adrenoceptor. Because of a significantly greater α2:α1 adrenoceptor affinity ratio, DEX demonstrates both pharmacokinetic and pharmacodynamics advantages without directed γ-aminobutyric acid (GABA)-ergic effect.[11] With sedative, anxiolytic, and analgesic features, it is a useful adjuvant to the anesthesia protocol. Additionally, it has been shown anesthetic-sparing and conscious sedation effects without causing deleterious respiratory depression, these properties make it superior to other agents in perioperative setting, especially in the elderly and pediatric population.[12] Thus it has been extensively studied in pediatric patients recently for premedication.[13] Although with various routes of administration, DEX is most usually used as continuous infusion, now it has been increasingly studied as an alternative to standard medicine for oral and intranasal administration.[14,15] Compared to intravenous and intranasal administration, oral route is noninvasive and easier to administer, meanwhile it has better medication acceptance for patients, particular for pediatric patients.[16]

However, there has been lack of studies on oral DEX premedication in adult patients. The aim of this prospective randomized double-blind study is to evaluate whether oral DEX premedication could increase sedation in order to reduce preoperative anxiety and inhibit stress response during general anesthesia tracheal intubation.