Reversing the Effects of 0.5% Bupivacaine

Phase 4

Completed

• Conditions: Anesthesia, Local
• Interventions: Drug: Saline Water (Control); Drug: OraVerse

• Registration Number: NCT02995291
• Lead Sponsor: Dalhousie University

Brief Summary

Clinical trials have shown phentolamine mesylate (PM), brand name OraVerse, to be effective at reducing the amount of time to reversal of local anesthesia with different dental anesthetics. However, to date no study investigated the efficacy of phentolamine mesylate to reverse anesthesia induced with the use of Bupivacaine.

The objective of the proposed research is to conduct a pilot-scale randomized clinical trial evaluating the difference in time required for the return of normal soft-tissue sensation and function in participants who have received 0.5% Bupivacaine HCl, 1:200,000 epinephrine, followed by an injection with either 1) OraVerse (phentolamine mesylate) or 2) sterile physiological water (control).

Detailed Description

Dental procedures often require the use of local anesthesia. The most common local anesthetic used is 2% Lidocaine 1:100,000 epinephrine. This local anesthetic can achieve soft tissue anesthesia for 180-300 minutes and pulpal anesthesia for 60 minutes. Unfortunately, for longer treatments this relatively short duration can lead to the loss of anesthetic effect before the end of the interventions. Time-demanding dental appointments include oral and periodontal surgeries, extensive restorative treatments, and even minor treatments when completed by dental students. Unfortunately, if a short acting anesthetic such as Lidocaine is being used during long lasting procedures, once the patients start feeling pain again, it may be difficult to reestablish deep pulpal anesthesia with a repeated injection due to tachyphylaxis. To avoid this situation long-acting local anesthetics could be selected instead. The only long-acting anesthetic available in dentistry is 0.5% Bupivacaine HCl, 1:200,000 epinephrine. Bupivacaine can produce soft tissue anesthesia for up to 12 hours (commonly 4 to 9 hours) and pulpal anesthesia for up to 7 hours (commonly 1.5 to 3 hours). Unfortunately, Bupivacaine is not often used for non-surgical procedures due to its very long soft tissue anesthesia that outlast treatments by several hours.

The effects of soft tissue anesthesia linger for some time after the administration of long acting local anesthetics such as Bupivacaine. This can lead to discomfort and occasionally injury from lip/tongue biting. Clinical trials have shown phentolamine mesylate (PM), brand name OraVerse, to be effective at reducing the amount of time to reversal of local anesthesia with different dental anesthetics. However, to date no study investigated the efficacy of phentolamine mesylate to reverse anesthesia induced with the use of Bupivacaine.

The objective of the proposed research is to conduct a pilot-scale randomized clinical trial evaluating the difference in time required for the return of normal soft-tissue sensation and function in participants who have received 0.5% Bupivacaine HCl, 1:200,000 epinephrine, followed by an injection with either 1) OraVerse (phentolamine mesylate) or 2) sterile physiological water (control). This will further advance our knowledge of both Bupivacaine and phentolamine mesylate as there are no current studies evaluating reversing the effect of Bupivacaine with PM.

It is hypothesized that phentolamine mesylate will reduce the duration of soft tissue anesthesia by 2.5 hours when compared with a control injection of saline water. It is anticipated that this study will determine the feasibility and sample size needed to conduct a full-scale multi-centre trial.

Study Timeline

• Study First Submitted: 2016-12-14
• Study First Submitted QC: 2016-12-15
• Study First Posted: 2016-12-16
• Study Start: 2017-02-10
• Primary Completion: 2019-05-15
• Study Completion: 2019-09-15
• Status Verified: 2020-01
• Last Update Submitted: 2020-01-27
• Last Update Posted: 2020-01-29

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 44

Inclusion Criteria

• 18 years of age or older
• capable of providing informed consent

Exclusion Criteria

• contra-indications for regular dental treatment
• medical history that contraindicates the use of epinephrine
• participant taken an opioid or an opioid like analgesic within 24 hours
• pregnant

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Control	Saline Water (Control)	1.7ml saline water
OraVerse	OraVerse	1.7ml OraVerse

Primary Outcome Measures

Name	Time	Method
Time to reversal of local anesthesia	8 hours

Trial Locations

Locations (1)

Dalhousie University Faculty of Dentistry; 🇨🇦 Halifax, Nova Scotia, Canada