Analgesic Effect of Peripheral Dexmedetomidine

NCT00971178 | Completed Phase 3 Results DMC

• 1 other identifier: 200807176008
• Study Type: interventional
• Target: 105
• Locations: 0 countries
• Sites: N/A

Brief Summary

Dexmedetomidine is an alpha 2-adrenoreceptor agonist, which provides sedation, analgesia and anxiolysis in clinical practice (Cortinez et al., 2004,Hall et al., 2000). Three types of alpha 2-adrenergic receptor subtypes are found in the human body and they have been designated alpha 2A, alpha 2B and alpha 2C. The alpha 2A subtype is most likely responsible for the analgesic properties of dexmedetomidine in both peripheral and central sites (Kingery et al., 2000, Smith et al., 2001). Activation of central alpha 2-adrenoreceptors in the locus ceruleus (Correa-Sales et al., 1992) and the dorsal horn of the spinal cord (Gaumann et al., 1992b) are responsible for both analgesic and sedative effects. Dexmedetomidine has a very high alpha 2 to alpha 1 selectivity, 1620 to 1, or approximately 8 times that of clonidine. It is also 4 to 6 times more potent than clonidine by weight (Bhana et al., 2000). Although dexmedetomidine produces dose dependent sedation upon intravenous administration, its the analgesic effect is of dexmedetomidine is more variable and controversial. In an ischaemic pain model in healthy volunteers, a single bolus of dexmedetomidine produced a 50% reduction in pain scores when compared to placebo (Jaakola et al., 1991). In another volunteer study using the cold pressor test, dexmedetomidine 1 µg/kg over 10 minutes followed by an infusion of 0.2 to 0.6 µg/kg/hour reduced pain by approximately 30% (Hall et al., 2000). However, when administered as a target controlled infusion at concentrations ranging from 0.09 to 1.23 ng/mL, dexmedetomidine had no analgesic effect in human volunteers subjected to heat and electrical pain, although sedation was produced (Memis et al., 2004). Clonidine and dexmedetomidine are two common alpha 2 agonists used clinically. Although clonidine former has been used successfully in regional analgesia and anesthesia (Gabriel et al., 2001)., There are only very few studies evaluating the peripheral analgesic effects of dexmedetomidine. Since acute postoperative dental pain is a common analgesia model (Cooper, 1991; US Food and Drug Administration 1992), the investigators conducted this study, aiming to assess the postoperative analgesic efficacy of peripheral dexmedetomidine after bilateral third molar surgery under general anaesthesia. The analgesic effects were compared up to the 72nd hour postoperatively in order to evaluate any potential preventive analgesic effect.

Conditions

Third Molar Extraction

Keywords

Analgesia; Dental pain; Dexmedetomidine; Pain; Peripheral effects

Outcome Measures

Primary Outcomes (1)

• Pain Score at Rest

  The Numerical Rating Scale (NRS) is used for pain score assessment at rest. It is a scale consists of 11 numbers in which 0 corresponds to no pain and 10 represents the worst pain imaginable. The NRS pain scores over postoperative 72 hours is expressed as Area Under Curve using the trapezoid rule and compared among the 3 groups using the Kruskal-Wallis test.

  72 hours after surgery

Study Arms (3)

Local Dexmedetomidine

ACTIVE COMPARATOR

Drug: local dexmedetomidine

Normal Saline

PLACEBO COMPARATOR

Drug: Peripheral normal saline

IV dexmedetomidine

ACTIVE COMPARATOR

Drug: IV dexmedetomidine

Interventions

local dexmedetomidine DRUG

Preoperative normal saline infusion and 1mcg/kg dexmedetomidine infiltrated locally to wound at the end of operation.

Also known as: Precedex

Local Dexmedetomidine

Peripheral normal saline DRUG

Same volume of normal saline as dexmedetomidine is infiltrated and IV infusion.

Normal Saline

IV dexmedetomidine DRUG

IV dexmedetomidine 1mcg/kg peroperative and normal saline infiltrated to wound at the end of operation

IV dexmedetomidine

Eligibility Criteria

• Age: 18 Years - 50 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64)

You may qualify if:

• American Society of Anesthesiologists (ASA) physical status I and II
• Age between 18 and 50 years of age with 4 bilateral impacted third molar teeth scheduled for extraction under general anaesthesia

You may not qualify if:

• Clinical history or electrocardiographic evidence of heart block
• Ischaemic heart disease
• Asthma
• Sleep apnoea syndrome
• Impaired liver or renal function
• Alcohol consumption in excess of 28 units per week
• Pregnancy
• Patient refusal
• Known psychiatric illness
• Chronic sedative or analgesic use, and regular use of or known allergy to dexmedetomidine, paracetamol or dextropropoxypheneopioids
• Patients with preoperative inflammation at the site of surgery were also excluded

Sponsors & Collaborators

• The University of Hong Kong: lead

MeSH Terms

Conditions

Agnosia; Toothache; Pain

Interventions

Dexmedetomidine

Condition Hierarchy (Ancestors)

Perceptual Disorders; Neurobehavioral Manifestations; Neurologic Manifestations; Nervous System Diseases; Signs and Symptoms; Pathological Conditions, Signs and Symptoms; Tooth Diseases; Stomatognathic Diseases; Facial Pain

Intervention Hierarchy (Ancestors)

Imidazoles; Azoles; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds

Results Point of Contact

• Title: Clinical Assistant Professor
• Organization: Department of Anaesthesiology, the University of Hong Kong

cheucw@hku.hk

852-22553303

Publication Agreements

• PI is Sponsor Employee: No
• Restrictive Agreement: No

Study Design

• Study Type: interventional
• Phase: phase 3
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor

Study Record Dates

• First Submitted: September 1, 2009
• First Posted: September 3, 2009
• Study Start: February 1, 2006
• Primary Completion: March 1, 2008
• Study Completion: March 1, 2008
• Last Updated: December 11, 2020
• Results First Posted: December 11, 2020

Record last verified: 2020-11