Pain
Conditions
Brief summary
For pain relief during a first trimester surgical aspiration, most providers use the paracervical block, either alone or in combination with other pain control techniques. Some providers use buffered lidocaine due to a belief that it decreases pain. Others use plain lidocaine. At our clinics, the standard pain management protocol is using 20 cc of 1% plain lidocaine in a two site injection. Few studies have compared buffered versus unbuffered lidocaine for paracervical blocks during first trimester uterine aspirations. This study seeks to determine if buffered lidocaine decreases injection pain versus plain lidocaine for paracervical blocks.
Detailed description
Potential participants will be identified at their office visits to the University Women's Health Specialists. If a patient desires uterine aspiration of a first trimester pregnancy or management of a failed pregnancy in the first trimester, they will first receive standard counseling. Only after providing written informed consent for the procedure will the patient's be screened for eligibility for our study. If the patient is eligible, she will be asked by a member of the research team if she is interested in participating. If she is, the study will be explained to her and written consent will be obtained after she is given the opportunity to have all of her questions answered. The patient will then complete a written questionnaire to collect demographic data. This prospective randomized control trial will consist of two study arms. Participants will be randomly assigned to Arm 1, where a paracervical block will be administered with 20 cc of 1% lidocaine, which is our standard office protocol, or to Arm 2, where a paracervical block will be administered with 20 cc of 1% lidocaine buffered with 8.4% sodium bicarbonate. Prior to the start of the study, study assignments will be generated in a 1:1 ratio. All patients who consent to the study will receive standard counseling prior to their procedure. The procedure will start with a bimanual exam by the provider. Next, the provider will place a speculum, cleanse the cervix with betadine solution, and place a single-tooth tenaculum on the anterior lip of the cervix. At this point, participants assigned to Arm 1 will receive a paracervical block loaded with 20 cc of 1% lidocaine and injected at 2, 4, 8 and 10 o'clock positions of the cervicovaginal junction. Participants assigned to Arm 2 will receive a paracervical block loaded with 18 cc of 1% lidocaine and 2 cc of 8.4% sodium bicarbonate and inject the block in the same fashion. The research assistant will ask the patient to verbally report their level of pain based on the 100 mm visual analog scale (VAS) at the following points of the procedure: 1. Prior to the start of the procedure (baseline anxiety) 2. After speculum placement 3. After paracervical block 4. After cervical dilation 5. After suction curettage 6. At end of procedure
Interventions
Paracervical block will be injected at 2 points at the cervicovaginal junction to decrease pain
Paracervical block will be injected at 2 points at the cervicovaginal junction to decrease pain
Sponsors
Study design
Masking description
A statistician not involved with the conduct of the study will use a computer random number generator to generate random permuted blocks. This statistician will place allocation assignment cards in sequentially numbered, sealed, opaque envelopes. A different randomization scheme will be used for each location, one at the Kapi'olani office and one at the Queen's office. A clinic staff member not involved with the conduct of the study will be trained specifically in the opening of the allocation envelopes. The staff member will be trained to open the envelope and remove the study card to read the allocation group: buffered lidocaine or plain lidocaine. The clinic staff member will then prepare the buffered lidocaine or plain lidocaine in an unlabeled syringe, and place it on the surgical tray.
Intervention model description
Randomized controlled trial
Eligibility
Inclusion criteria
* Pregnant women 14 years and older * Desiring uterine aspiration for pregnancy or surgical management of a miscarriage * Gestational age up to 13 weeks and 6 days to be established by best dating (i.e. last menstrual period or earliest ultrasound) * Treatment plan involves outpatient uterine aspiration * Participant able to provide informed consent in English and willing to participate in the study
Exclusion criteria
* Unable to read, speak, or understand English * Unable to provide informed consent * Currently incarcerated * Under the age of 14 years * Contraindications to receiving lidocaine or buffered lidocaine
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Injection Pain | Immediately after injection of the paracervical block | For the primary outcome, pain immediately after paracervical block injection was measured by a scale. The scale used was the 100-mm visual analog scale. The minimum score was 0 and the maximum score was 100. Higher numbers indicate worse pain. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Pain After Speculum Placement, Cervical Dilation, and Aspiration | Immediately after speculum placement, cervical dilation, uterine aspiration | Pain scores were measured at multiple points throughout the procedure. Pain scores were measured using a 100 mm visual analog scale with 0 being no pain and 100 being the worst pain ever. |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Standard Paracervical Block A paracervical block will be administered with 20 cc of 1% lidocaine, which is our standard office protocol
Lidocaine: Paracervical block will be injected at 4 points at the cervicovaginal junction to decrease pain | 48 |
| Buffered Lidocaine Paracervical Block A paracervical block will be administered with 20 cc of 1% lidocaine buffered with 8.4% sodium bicarbonate
Lidocaine-Sodium Bicarbonate: Paracervical block will be injected at 4 points at the cervicovaginal junction to decrease pain | 50 |
| Total | 98 |
Baseline characteristics
| Characteristic | Standard Paracervical Block | Buffered Lidocaine Paracervical Block | Total |
|---|---|---|---|
| Age, Continuous | 30 years STANDARD_DEVIATION 6 | 28 years STANDARD_DEVIATION 6 | 29 years STANDARD_DEVIATION 6 |
| Race/Ethnicity, Customized American Indian/Alaska Native | 3 Participants | 2 Participants | 5 Participants |
| Race/Ethnicity, Customized Asian | 26 Participants | 31 Participants | 57 Participants |
| Race/Ethnicity, Customized Black/African American | 3 Participants | 2 Participants | 5 Participants |
| Race/Ethnicity, Customized Hispanic/Latino | 5 Participants | 4 Participants | 9 Participants |
| Race/Ethnicity, Customized Native Hawaiian/Pacific Islander | 23 Participants | 22 Participants | 45 Participants |
| Race/Ethnicity, Customized Other | 0 Participants | 1 Participants | 1 Participants |
| Race/Ethnicity, Customized White/Caucasian | 18 Participants | 17 Participants | 35 Participants |
| Sex: Female, Male Female | 48 Participants | 50 Participants | 98 Participants |
| Sex: Female, Male Male | 0 Participants | 0 Participants | 0 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 48 | 0 / 50 |
| other Total, other adverse events | 0 / 48 | 0 / 50 |
| serious Total, serious adverse events | 0 / 48 | 0 / 50 |
Outcome results
Injection Pain
For the primary outcome, pain immediately after paracervical block injection was measured by a scale. The scale used was the 100-mm visual analog scale. The minimum score was 0 and the maximum score was 100. Higher numbers indicate worse pain.
Time frame: Immediately after injection of the paracervical block
| Arm | Measure | Value (MEDIAN) |
|---|---|---|
| Standard Paracervical Block | Injection Pain | 44.5 units on a scale |
| Buffered Lidocaine Paracervical Block | Injection Pain | 30 units on a scale |
Pain After Speculum Placement, Cervical Dilation, and Aspiration
Pain scores were measured at multiple points throughout the procedure. Pain scores were measured using a 100 mm visual analog scale with 0 being no pain and 100 being the worst pain ever.
Time frame: Immediately after speculum placement, cervical dilation, uterine aspiration
| Arm | Measure | Group | Value (MEDIAN) | Dispersion |
|---|---|---|---|---|
| Standard Paracervical Block | Pain After Speculum Placement, Cervical Dilation, and Aspiration | After insertion of speculum | 13 units on a scale | Standard Deviation 20.7 |
| Standard Paracervical Block | Pain After Speculum Placement, Cervical Dilation, and Aspiration | After cervical dilation | 60.06 units on a scale | Standard Deviation 26.3 |
| Standard Paracervical Block | Pain After Speculum Placement, Cervical Dilation, and Aspiration | After uterine aspiration | 67.5 units on a scale | Standard Deviation 26.44 |
| Buffered Lidocaine Paracervical Block | Pain After Speculum Placement, Cervical Dilation, and Aspiration | After insertion of speculum | 17 units on a scale | Standard Deviation 21.85 |
| Buffered Lidocaine Paracervical Block | Pain After Speculum Placement, Cervical Dilation, and Aspiration | After cervical dilation | 55 units on a scale | Standard Deviation 29.57 |
| Buffered Lidocaine Paracervical Block | Pain After Speculum Placement, Cervical Dilation, and Aspiration | After uterine aspiration | 69 units on a scale | Standard Deviation 28.54 |