Labor Pain
Conditions
Keywords
Local anesthetic, Labor epidural
Brief summary
This study will compare and determine the most ideal local anesthetic (LA) solution to activate a labor epidural: lidocaine, bupivacaine, or a combination of bupivacaine plus lidocaine.
Detailed description
The most common and effective method for controlling labor pains is a local anesthetic (LA) infusion through a lumbar epidural. To achieve adequate pain control during the first stage of labor - onset of contractions to complete cervical dilation - nerve fibers up to the T10 dermatome must be anesthetized. When a patient is in active labor and an epidural catheter is placed, the anesthesiologist must activate the epidural by administering LA through the epidural to promote spread of the LA in the epidural space to anesthetize the nerve fibers involved in the conduction of labor pains. The ideal LA to achieve this goal is one that would allow for the fastest onset to achieve quick pain relief with the fewest side effects. Two commonly used LA to provide labor analgesia are bupivacaine and lidocaine. When low concentrations - 0.25% bupivacaine and 1% lidocaine - are used for labor analgesia, both of these LA can be administered safely with very little concern of major adverse effects associated with LA toxicity. Given that there is limited and conflicting evidence for the usefulness of the bupivacaine and lidocaine mixture especially as it relates to labor epidural activation, we hope to readdress these questions in an effort to determine whether or not the LA combination offers any distinct advantage over the individual LA. The investigators intend to determine the time it takes to achieve an adequate level (T10) for labor analgesia, the total spread of local anesthetic, and the degree of motor block as these factors will be important in determining the most optimal LA solution to activate a labor epidural. With the results from this study, the investigators hope to recommend a LA solution that will allow for the fastest pain relief in the laboring mother with the fewest side effects.
Interventions
DRUG1% Lidocaine
10 mL of 1% lidocaine
10 mL of 0.25% bupivacaine
5 mL of 1% lidocaine and 5 mL of 0.25% bupivacaine
Sponsors
University of Alabama at Birmingham
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
TRIPLE (Subject, Caregiver, Investigator)
Eligibility
Sex/Gender
FEMALE
Age
19 Years to 60 Years
Healthy volunteers
Yes
Inclusion criteria
* Pregnant patients over the age of 19 who are scheduled for an induction of labor and request an epidural are eligible for the study
Exclusion criteria
* age \<19 * allergy to the drug or drug class * preexisting neuropathy * history of back pain prior to pregnancy or history of back surgery * history of chronic opioid use * history of hypertension or hypertensive disorders of pregnancy * congenital or acquired cardiac disease * contraindication to epidural placement (patient refusal, severe coagulopathy, infection at site of epidural needle insertion, severe hypovolemia)
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Time to Achieve an Adequate Epidural Level for Labor Analgesia | Baseline to 1 hour | time it takes to achieve a T10 dermatome level by pinprick. A T10 dermatome level is what is needed to control labor pain. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Number of Patients Who Achieve Adequate Analgesia | Baseline to 1 hour | The number of patients who received an adequate epidural level of T10 or higher |
| Degree of Motor Block | Baseline to 1 hour | degree of motor block which means the amount of weakness in the legs experienced by the participants. this was determined by using the Bromage scale where 4 = greatest amount of motor block or muscle weakness and 0 = the least amount of motor block. |
| Number of Patients Who Experienced of Maternal Hypotension | Baseline to 1 hour | Number of patients who experienced maternal hypotension defined as a blood pressure (BP) \>20% decline from baseline and need for vasopressor therapy |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| 1% Lidocaine Patients randomized into the lidocaine group will receive 10 mL of 1% lidocaine
1% Lidocaine: 10 mL of 1% lidocaine | 25 |
| 0.25% Bupivacaine Patients randomized into the bupivacaine group will receive 10 mL of 0.25% bupivacaine
0.25% Bupivacaine: 10 mL of 0.25% bupivacaine | 25 |
| Bupivacaine Plus Lidocaine Patients randomized into the bupivacaine group will receive 5 mL of 0.25% bupivacaine and 5 mL of 1% lidocaine.
Bupivacaine plus Lidocaine: 5 mL of 1% lidocaine and 5 mL of 0.25% bupivacaine | 25 |
| Total | 75 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 | FG002 |
|---|---|---|---|---|
| Overall Study | Adverse Event | 1 | 0 | 0 |
| Overall Study | Physician Decision | 1 | 0 | 2 |
Baseline characteristics
| Characteristic | 1% Lidocaine | 0.25% Bupivacaine | Bupivacaine Plus Lidocaine | Total |
|---|---|---|---|---|
| Age, Categorical <=18 years | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical >=65 years | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical Between 18 and 65 years | 25 Participants | 25 Participants | 25 Participants | 75 Participants |
| Race (NIH/OMB) American Indian or Alaska Native | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Asian | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Black or African American | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) More than one race | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 25 Participants | 25 Participants | 25 Participants | 75 Participants |
| Race (NIH/OMB) White | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Sex: Female, Male Female | 25 Participants | 25 Participants | 25 Participants | 75 Participants |
| Sex: Female, Male Male | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk | EG002 affected / at risk |
|---|---|---|---|
| deaths Total, all-cause mortality | 0 / 23 | 0 / 25 | 0 / 23 |
| other Total, other adverse events | 1 / 23 | 0 / 25 | 0 / 23 |
| serious Total, serious adverse events | 0 / 23 | 0 / 25 | 0 / 23 |
Outcome results
Primary
Time to Achieve an Adequate Epidural Level for Labor Analgesia
time it takes to achieve a T10 dermatome level by pinprick. A T10 dermatome level is what is needed to control labor pain.
Time frame: Baseline to 1 hour
Population: In the 1% lidocaine group, 1 participant experienced an adverse event and was removed from analysis and 1 participant was removed because they did not receive the study drug. In the bupivacaine plus lidocaine group 2 patients were removed because they did not receive the study drug.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| 1% Lidocaine | Time to Achieve an Adequate Epidural Level for Labor Analgesia | 7.0 minutes | Standard Deviation 3.9 |
| 0.25% Bupivacaine | Time to Achieve an Adequate Epidural Level for Labor Analgesia | 11.0 minutes | Standard Deviation 5.8 |
| Bupivacaine Plus Lidocaine | Time to Achieve an Adequate Epidural Level for Labor Analgesia | 8.5 minutes | Standard Deviation 4.6 |
Secondary
Degree of Motor Block
degree of motor block which means the amount of weakness in the legs experienced by the participants. this was determined by using the Bromage scale where 4 = greatest amount of motor block or muscle weakness and 0 = the least amount of motor block.
Time frame: Baseline to 1 hour
Population: In the 1% lidocaine group, 1 participant experienced an adverse event and was removed from analysis and 1 participant was removed because they did not receive the study drug. In the bupivacaine plus lidocaine group 2 patients were removed because they did not receive the study drug.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| 1% Lidocaine | Degree of Motor Block | 2.0 Bromage Score | Standard Deviation 0.6 |
| 0.25% Bupivacaine | Degree of Motor Block | 1.7 Bromage Score | Standard Deviation 1 |
| Bupivacaine Plus Lidocaine | Degree of Motor Block | 1.9 Bromage Score | Standard Deviation 0.9 |
Secondary
Number of Patients Who Achieve Adequate Analgesia
The number of patients who received an adequate epidural level of T10 or higher
Time frame: Baseline to 1 hour
Population: In the 1% lidocaine group, 1 participant experienced an adverse event and was removed from analysis and 1 participant was removed because they did not receive the study drug. In the bupivacaine plus lidocaine group 2 patients were removed because they did not receive the study drug.
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| 1% Lidocaine | Number of Patients Who Achieve Adequate Analgesia | 23 Participants |
| 0.25% Bupivacaine | Number of Patients Who Achieve Adequate Analgesia | 25 Participants |
| Bupivacaine Plus Lidocaine | Number of Patients Who Achieve Adequate Analgesia | 23 Participants |
Secondary
Number of Patients Who Experienced of Maternal Hypotension
Number of patients who experienced maternal hypotension defined as a blood pressure (BP) \>20% decline from baseline and need for vasopressor therapy
Time frame: Baseline to 1 hour
Population: In the 1% lidocaine group, 1 participant experienced an adverse event and was removed from analysis and 1 participant was removed because they did not receive the study drug. In the bupivacaine plus lidocaine group 2 patients were removed because they did not receive the study drug.
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| 1% Lidocaine | Number of Patients Who Experienced of Maternal Hypotension | 4 Participants |
| 0.25% Bupivacaine | Number of Patients Who Experienced of Maternal Hypotension | 0 Participants |
| Bupivacaine Plus Lidocaine | Number of Patients Who Experienced of Maternal Hypotension | 0 Participants |