Premedication with Dexmedetomidine increases sedation and reduces stress due to tracheal intubation

The preoperative time is stressful for both patients and family members. Preoperative anxiety should be relieved adequately to improve perioperative outcomes. Various medicines like midazolam, opioids and atropine have been used. Respiratory depression and cognition changes postoperatively are adverse effects secondary to midazolam.

Dexmedetomidine (DEX) has sedative, anxiolytic, and analgesic features and is superior for the elderly and children. There is a lack of data on oral DEX premedication in adult patients.

Considering the above background, a prospective randomized, double-blind study was conducted by Jun Xiong and colleagues to evaluate if oral DEX premedication increases sedation, reduces preoperative anxiety, and inhibits stress response during general anaesthesia tracheal intubation.

The study points are:

• 100 adult patients (ASA I and II) undergoing elective neurosurgery were divided into a control group and a DEX group.
• The Control group had 50 patients, and the DEX group had 50 patients.
• DEX administration was done orally two hours before general anaesthesia induction.
• After induction and confirmation of muscle relaxation, tracheal intubation was performed with a video laryngoscope.
• Patients were given 4 μg/kg dexmedetomidine orally pre-anesthesia 120 min.
• Hemodynamic variables were monitored and recorded. (premedication to 10 min after tracheal intubation).
• Richmond Agitation Sedation Scale (RASS) and Numerical Rating Scale were used to evaluate the sedation level of all patients.(primary outcome).
• After tracheal intubation, the blood sample was drain from the radial atrial line to measure levels of hormone (ACTH and cortisol).
• DEX administration increased sedation level compared to the placebo group, with RASS scores of -0.90 and 1.12 in the DEX and control group.
• DEX premedication reduced blood cortisol levels suggesting lower stress levels than the control group.
• RASS scores at 60 min after premedication and on arrival in the operating room were significantly reduced in the DEX group.
• Oral DEX premedication increased thirst intensity and satisfaction of family members.
• The cortisol level was deduced after tracheal intubation by oral DEX premedication.
• Oral DEX premedication reduced heart rate (HR) and mean arterial pressure (MAP).
• The lowest HR was significantly lower in the DEX group.
• Oral DEX premedication might reduce HR from premedication to 10 min after tracheal intubation.
• MAP was reduced just from premedication to on arrival in the operating room.
• There were similarities in the total induction dosages of propofol, midazolam, sulfentanil and rocuronium in two groups.
• The complications of anaesthesia induction and rescue dopamine therapy cases were similar in the two groups.

To conclude, oral dexmedetomidine as premedication before neurosurgery increases preoperative sedation. This also reduced the stress reaction induced by tracheal intubation under general anaesthesia.

The sparing-anaesthetic effect of 4 μg/kg DEX oral premedication was not significant in this study and this should be studied in the future, they said.

Further reading:

Xiong, J., Gao, J., Pang, Y. et al. Dexmedetomidine premedication increases preoperative sedation and inhibits stress induced by tracheal intubation in adult: a prospective randomized double-blind clinical study. BMC Anesthesiol 22, 398 (2022). https://doi.org/10.1186/s12871-022-01930-z