Healthy
Conditions
Keywords
To determine if topical nitroglycerin acts to vasodilate the radial artery by a direct local action, or by systemic vasodilation, To determine if topical nitroglycerin dilates the radial artery in the presence of local anesthetic agents used in cardiac catheterization
Brief summary
The radial artery, which is located on the outer side of the forearm, can be used in interventional procedures, such as cardiac catheterization, to provide access to the arterial blood supply. In order to facilitate successful catheterization of the artery, a dilated artery and one free of arterial spasm is desirable. The proposed study will randomize twenty three healthy subjects in 2 visits to determine the effect of topical nitroglycerin on radial artery vasodilation. Radial artery diameter will be measured with ultrasound at regular intervals up to two hours.
Detailed description
During the first study visit, as a dose-optimizing study, each subject will be randomly assigned to one of two Dose-Test arms to receive either 15mg or 30mg of nitroglycerin on one wrist and placebo on the other. Radial artery diameter will be measured with ultrasound at regular intervals up to two hours. On the second study visit, the same participants will be randomly assigned to one of two Combination-Test arms to receive bilateral topical application of either 20mg or 40mg of lidocaine; the lidocaine will be applied in combination with 30mg of nitroglycerin on one wrist and in combination with placebo on the other wrist. Measurements of radial artery diameter will be performed as in the first visit.
Interventions
DRUGNitroglycerin 15mg
15mg Nitroglycerin applied topically to one wrist
DRUGNitroglycerin 30mg
30mg Nitroglycerin applied topically to one wrist
DRUGLidocaine 20mg
20mg Lidocaine applied topically to one wrist in combination with nitroglycerin or placebo
DRUGLidocaine 40mg
40mg Lidocaine applied topically to one wrist in combination with nitroglycerin or placebo
DRUGPlacebo
Topical skin moisturizing cream with same appearance as active agent
Sponsors
University of California, San Francisco
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
OTHER
Masking
SINGLE (Subject)
Eligibility
Sex/Gender
ALL
Age
18 Years to 35 Years
Healthy volunteers
Yes
Inclusion criteria
* Willing and able to give written informed consent and comply with study requirements * Patient who speak English
Exclusion criteria
* Presence or history of liver, cardiovascular, rheumatologic, cancer or renal disease. * Current treatment with any vasodilator therapy * Systolic blood pressure of less than 90 mmHg * History of radial artery catheterization within the previous year * Absence of radial artery blood flow in one or both arms * Pregnancy. * Active infection * Staff members of the Cardiac Catheterization Laboratory.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Percent Change in Diameter of Radial Artery as a Dose Test for Nitroglycerin | Baseline, 10 minutes, 30 minutes, 60 minutes, and 120 minutes after topical application at Visit 1 | Radial artery diameter was measured with ultrasonography using a high-frequency (13 MHz) linear array transducer 2 cm proximal to the radial styloid process. |
| Percent Change From Baseline in Radial Artery Diameter to Compare Combination of Nitroglycerin or Placebo and Lidocaine (20mg or 40mg) | Baseline, 10 minutes, 30 minutes, 60 minutes, and 120 minutes after topical application at Visit 2 | Radial artery diameter was measured with ultrasonography using a high-frequency (13 MHz) linear array transducer 2 cm proximal to the radial styloid process. To compare combination of (Lidocaine + Nitroglycerin) or (Lidocaine + placebo), at visit 2, participants randomized to Comparison A received 30mg NTG + 20mg Lidocaine on one wrist, and placebo + 20mg Lidocaine on the other wrist; participants randomized to Comparison B received 30mg Nitroglycerin + 40mg Lidocaine on one wrist, and placebo + 40mg Lidocaine on the other wrist. |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Overall Study Healthy subjects older than 18 years were recruited and randomly assigned to one of two study arms on each of two separate study visits. Visit 1: 15mg Nitroglycerin vs. 30 mg Nitroglycerin on one wrist and placebo on the other wrist. Visit 2: 20mg Lidocaine vs. 40mg Lidocaine in combination with Nitroglycerin on one wrist and with placebo on the other wrist. | 19 |
| Total | 19 |
Baseline characteristics
| Characteristic | Overall Study |
|---|---|
| Age, Categorical <=18 years | 0 Participants |
| Age, Categorical >=65 years | 0 Participants |
| Age, Categorical Between 18 and 65 years | 19 Participants |
| Age, Continuous | 29 years STANDARD_DEVIATION 4 |
| Region of Enrollment United States | 19 participants |
| Sex: Female, Male Female | 13 Participants |
| Sex: Female, Male Male | 6 Participants |
Adverse events
| Event type | EG000 affected / at risk |
|---|---|
| deaths Total, all-cause mortality | — / — |
| other Total, other adverse events | 0 / 19 |
| serious Total, serious adverse events | 0 / 19 |
Outcome results
Primary
Percent Change From Baseline in Radial Artery Diameter to Compare Combination of Nitroglycerin or Placebo and Lidocaine (20mg or 40mg)
Radial artery diameter was measured with ultrasonography using a high-frequency (13 MHz) linear array transducer 2 cm proximal to the radial styloid process. To compare combination of (Lidocaine + Nitroglycerin) or (Lidocaine + placebo), at visit 2, participants randomized to Comparison A received 30mg NTG + 20mg Lidocaine on one wrist, and placebo + 20mg Lidocaine on the other wrist; participants randomized to Comparison B received 30mg Nitroglycerin + 40mg Lidocaine on one wrist, and placebo + 40mg Lidocaine on the other wrist.
Time frame: Baseline, 10 minutes, 30 minutes, 60 minutes, and 120 minutes after topical application at Visit 2
Population: 10 participants (20 wrists) received 30mg NTG + 20mg Lidocaine on one wrist, and placebo + 20mg Lidocaine on the other wrist; 9 participants (18 wrists) received 30mg NTG + 40mg Lidocaine on one wrist, and placebo + 40mg Lidocaine on the other wrist.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Placebo | Percent Change From Baseline in Radial Artery Diameter to Compare Combination of Nitroglycerin or Placebo and Lidocaine (20mg or 40mg) | 10 minutes | 4 percent diameter change | Standard Deviation 3.6 |
| Placebo | Percent Change From Baseline in Radial Artery Diameter to Compare Combination of Nitroglycerin or Placebo and Lidocaine (20mg or 40mg) | 30 minutes | 5.3 percent diameter change | Standard Deviation 5.8 |
| Placebo | Percent Change From Baseline in Radial Artery Diameter to Compare Combination of Nitroglycerin or Placebo and Lidocaine (20mg or 40mg) | 60 minutes | 8.4 percent diameter change | Standard Deviation 7.4 |
| Placebo | Percent Change From Baseline in Radial Artery Diameter to Compare Combination of Nitroglycerin or Placebo and Lidocaine (20mg or 40mg) | 120 minutes | 5.7 percent diameter change | Standard Deviation 6.8 |
| 15mg Nitroglycerin | Percent Change From Baseline in Radial Artery Diameter to Compare Combination of Nitroglycerin or Placebo and Lidocaine (20mg or 40mg) | 30 minutes | 11.0 percent diameter change | Standard Deviation 10.6 |
| 15mg Nitroglycerin | Percent Change From Baseline in Radial Artery Diameter to Compare Combination of Nitroglycerin or Placebo and Lidocaine (20mg or 40mg) | 60 minutes | 18.2 percent diameter change | Standard Deviation 9.4 |
| 15mg Nitroglycerin | Percent Change From Baseline in Radial Artery Diameter to Compare Combination of Nitroglycerin or Placebo and Lidocaine (20mg or 40mg) | 120 minutes | 18.5 percent diameter change | Standard Deviation 8.7 |
| 15mg Nitroglycerin | Percent Change From Baseline in Radial Artery Diameter to Compare Combination of Nitroglycerin or Placebo and Lidocaine (20mg or 40mg) | 10 minutes | 4.9 percent diameter change | Standard Deviation 7.2 |
| 30mg Nitroglycerin | Percent Change From Baseline in Radial Artery Diameter to Compare Combination of Nitroglycerin or Placebo and Lidocaine (20mg or 40mg) | 60 minutes | 2.5 percent diameter change | Standard Deviation 3.2 |
| 30mg Nitroglycerin | Percent Change From Baseline in Radial Artery Diameter to Compare Combination of Nitroglycerin or Placebo and Lidocaine (20mg or 40mg) | 30 minutes | 2.9 percent diameter change | Standard Deviation 1.8 |
| 30mg Nitroglycerin | Percent Change From Baseline in Radial Artery Diameter to Compare Combination of Nitroglycerin or Placebo and Lidocaine (20mg or 40mg) | 120 minutes | 4.1 percent diameter change | Standard Deviation 3.9 |
| 30mg Nitroglycerin | Percent Change From Baseline in Radial Artery Diameter to Compare Combination of Nitroglycerin or Placebo and Lidocaine (20mg or 40mg) | 10 minutes | 1.6 percent diameter change | Standard Deviation 3 |
| Lidocaine 40mg + Nitroglycerin 30mg | Percent Change From Baseline in Radial Artery Diameter to Compare Combination of Nitroglycerin or Placebo and Lidocaine (20mg or 40mg) | 120 minutes | 22.1 percent diameter change | Standard Deviation 12 |
| Lidocaine 40mg + Nitroglycerin 30mg | Percent Change From Baseline in Radial Artery Diameter to Compare Combination of Nitroglycerin or Placebo and Lidocaine (20mg or 40mg) | 30 minutes | 10.6 percent diameter change | Standard Deviation 6.5 |
| Lidocaine 40mg + Nitroglycerin 30mg | Percent Change From Baseline in Radial Artery Diameter to Compare Combination of Nitroglycerin or Placebo and Lidocaine (20mg or 40mg) | 10 minutes | 3.4 percent diameter change | Standard Deviation 3 |
| Lidocaine 40mg + Nitroglycerin 30mg | Percent Change From Baseline in Radial Artery Diameter to Compare Combination of Nitroglycerin or Placebo and Lidocaine (20mg or 40mg) | 60 minutes | 17.2 percent diameter change | Standard Deviation 9.2 |
Primary
Percent Change in Diameter of Radial Artery as a Dose Test for Nitroglycerin
Radial artery diameter was measured with ultrasonography using a high-frequency (13 MHz) linear array transducer 2 cm proximal to the radial styloid process.
Time frame: Baseline, 10 minutes, 30 minutes, 60 minutes, and 120 minutes after topical application at Visit 1
Population: 19 participants were randomized to receive 15mg (n=12) or 30mg (n=7) nitroglycerin on one wrist, and placebo on the other
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Placebo | Percent Change in Diameter of Radial Artery as a Dose Test for Nitroglycerin | 10 minutes | -0.8 percent diameter change | Standard Deviation 0.5 |
| Placebo | Percent Change in Diameter of Radial Artery as a Dose Test for Nitroglycerin | 30 minutes | 2.5 percent diameter change | Standard Deviation 12.5 |
| Placebo | Percent Change in Diameter of Radial Artery as a Dose Test for Nitroglycerin | 60 minutes | 3.3 percent diameter change | Standard Deviation 6.5 |
| Placebo | Percent Change in Diameter of Radial Artery as a Dose Test for Nitroglycerin | 120 minutes | 5.9 percent diameter change | Standard Deviation 6.5 |
| 15mg Nitroglycerin | Percent Change in Diameter of Radial Artery as a Dose Test for Nitroglycerin | 120 minutes | 8.8 percent diameter change | Standard Deviation 10.1 |
| 15mg Nitroglycerin | Percent Change in Diameter of Radial Artery as a Dose Test for Nitroglycerin | 10 minutes | -0.2 percent diameter change | Standard Deviation 2.8 |
| 15mg Nitroglycerin | Percent Change in Diameter of Radial Artery as a Dose Test for Nitroglycerin | 60 minutes | 10.2 percent diameter change | Standard Deviation 5.4 |
| 15mg Nitroglycerin | Percent Change in Diameter of Radial Artery as a Dose Test for Nitroglycerin | 30 minutes | 0.8 percent diameter change | Standard Deviation 3.5 |
| 30mg Nitroglycerin | Percent Change in Diameter of Radial Artery as a Dose Test for Nitroglycerin | 120 minutes | 28.5 percent diameter change | Standard Deviation 12.1 |
| 30mg Nitroglycerin | Percent Change in Diameter of Radial Artery as a Dose Test for Nitroglycerin | 30 minutes | 14.9 percent diameter change | Standard Deviation 18.1 |
| 30mg Nitroglycerin | Percent Change in Diameter of Radial Artery as a Dose Test for Nitroglycerin | 60 minutes | 21.5 percent diameter change | Standard Deviation 6.6 |
| 30mg Nitroglycerin | Percent Change in Diameter of Radial Artery as a Dose Test for Nitroglycerin | 10 minutes | 6.4 percent diameter change | Standard Deviation 4.5 |