Lidocaine Injections for Labor Pain

Overseen By Jeremy Reeves, BS

Age: 18+

Sex: Female

Trial Phase: Academic

Sponsor: Ohio State University

Must not be taking: Opioids, IV magnesium sulfate

Disqualifiers: Cesarean delivery, Diabetes, BMI ≥ 35, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Approved in 3 Jurisdictions This treatment is already approved in other countries

Compensation: Varies

Number of Visits: 1

Duration: 1 day

50 Participants Needed

Trial Summary

Will I have to stop taking my current medications?

The trial does not specify if you need to stop taking your current medications, but it excludes those who have taken opioids in the last 4 hours or IV magnesium sulfate in the last 24 hours.

What evidence supports the effectiveness of the drug lidocaine for labor pain relief?

Research shows that a lower concentration of lidocaine (0.5%) can quickly and effectively provide pain relief when used as an epidural during early labor. This suggests that lidocaine is a fast-acting and safe option for managing labor pain. ^{1 2 3 4 5}

Is lidocaine safe for use in humans?

Lidocaine is generally safe for use in humans, but there are rare cases of allergic reactions and potential overdose risks, especially in children. Most side effects are mild, such as bruising or swelling at the injection site, but serious allergic reactions can occur, so sensitivity testing is important. ^{6 7 8 9 10}

How does the drug lidocaine differ from other treatments for labor pain?

Lidocaine injections for labor pain are unique because they provide fast-onset and effective pain relief when administered as an epidural bolus, unlike other local anesthetics like bupivacaine or ropivacaine, which have a slower onset. This makes lidocaine a quick and safe option for initiating pain relief during the early stages of labor. ^{1 2 11 12 13}

What is the purpose of this trial?

The purpose of this study is to explore the differences between the pain associated with epidural Tuohy needle insertion with prior administration of subcutaneous or intradermal lidocaine using two different pain assessment tools (numerical rate scale (NRS) and Critical-Care Pain Observation Tool (CPOT)) in parturient women requesting epidural analgesia for laboring pain. Subjects will go through the following study procedures: review of medical history prior to surgery. Subjects will be randomly assigned to one of the two study groups in a 1:1 ratio to one of the two different standard methods to administer lidocaine prior to epidural Tuohy needle insertion: intradermal or subcutaneous lidocaine administration. Prior to insertion of the Tuohy epidural needle, each patient will receive an injection of 3 mL 1% lidocaine either intradermally (Group Intradermal) or subcutaneously (Group Subcutaneous). A blinded observer (positioned in front of the patient and unable to see the procedure) will record baseline NRS scores, HR, and BP after the patient has been positioned for the epidural procedure and prior to the administration of lidocaine. During the procedure, the blinded observer will objectively record patient's vocal responses, facial expressions, bodily movements, and muscle tension (caused by pain reflex) using the CPOT and NRS scales during lidocaine administration and the first Tuohy needle insertion. After each injection, the blinded observer will record the corresponding heart rate. When the procedural anesthesiologist has exited the room, the blinded observer will then collect the patient's procedure satisfaction score from 0 (worst satisfaction) to 10 (most satisfaction) at the conclusion of the procedure. Likewise, the blinded observer will also collect the final post-procedure heart rate and blood pressure.

Eligibility Criteria

This trial is for women in labor who want epidural analgesia to manage pain. Participants must be eligible for the study based on their medical history reviewed before surgery. There are no specific inclusion or exclusion criteria provided.

Inclusion Criteria

I can understand and give consent in English.

Parturient women requesting epidural analgesia for laboring pain

Exclusion Criteria

BMI ≥ 35

Chronic pain patients

Opioid use disorder

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants receive either intradermal or subcutaneous lidocaine prior to epidural Tuohy needle insertion, with pain and physiological responses recorded

1 day

1 visit (in-person)

Follow-up

Participants' procedural satisfaction and physiological responses are assessed 30 minutes after the procedure

30 minutes

Treatment Details

Interventions

• 1% Lidocaine Injection

Trial Overview The study compares two ways of giving lidocaine, a numbing medication, before inserting an epidural needle: one group gets it under the skin (subcutaneous), and another just below the surface of the skin (intradermal). Pain levels will be measured using two scales by someone who can't see which method was used.

Participant Groups

Group I: INTRADERMAL Active Control 1 Intervention

Prior to insertion of the Tuohy epidural needle, each patient will receive an injection of 3 mL 1% lidocaine either intradermally (Group Intradermal).

Group II: SUBCUTANEOUS Active Control 1 Intervention

Prior to insertion of the Tuohy epidural needle, each patient will receive an injection of 3 mL 1% lidocaine subcutaneously (Group Subcutaneous).

Who Is Running the Clinical Trial?

Ohio State University

Lead Sponsor

Trials

891

Recruited

2,659,000+

Findings from Research

In a study involving 48 unmedicated laboring parturients, lidocaine 100 mg was found to be a highly sensitive marker for detecting intravascular injection, achieving a sensitivity of 100% when combined with symptoms of tinnitus and metallic taste.

The combination of tinnitus and metallic taste was identified as the most reliable indicator of intravenous injection, while the specificity for these symptoms was lower, indicating that while they are good indicators, they may not be definitive on their own.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Epidural test dose: lidocaine 100 mg, not chloroprocaine, is a symptomatic marker of i.v. injection in labouring parturients. Colonna-Romano, P., Lingaraju, N., Braitman, LE.[2018]

In a study of 32 patients, 0.5% lidocaine was found to be a fast-onset and effective local anesthetic for initiating epidural analgesia in early labor, compared to traditional agents like bupivacaine.

The use of lidocaine for labor analgesia demonstrated safety and efficacy, suggesting it could be a preferable option for quicker pain relief during the early stages of labor.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Low concentration lidocaine (0.5%) bolus epidurally can initiate fast-onset, effective and safe analgesia for early stage labor. Liu, H., Yao, S., Rosinia, F.[2014]

In a study involving 81 women in labor, bupivacaine was found to be significantly more potent than lidocaine, with a minimum local analgesic concentration (MLAC) of 0.065% for bupivacaine compared to 0.37% for lidocaine, indicating that bupivacaine is 5.7 times more effective in providing pain relief.

The study established a clinical model to determine effective concentrations of local anesthetics, which can help in assessing the analgesic potency of other epidural analgesics in future research.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Determination of the minimum local analgesic concentrations of epidural bupivacaine and lidocaine in labor. Columb, MO., Lyons, G.[2022]

In a study of 144 women, the use of lidocaine-prilocaine (LP) cream resulted in significantly lower pain scores during perineal repair compared to lidocaine infiltration, indicating it is a more effective analgesic option.

The LP cream not only reduced pain but also shortened the duration of the repair process and led to higher satisfaction rates among participants, with no significant differences in side effects between the two methods.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Topical lidocaine-prilocaine cream versus lidocaine infiltration for pain relief during repair of perineal tears after vaginal delivery: randomized clinical trial. Abbas, AM., Abdel Hafiz, HA., Abdelhafez, AM., et al.[2019]

In a study of 57 first-time mothers, those who delivered vaginally required significantly lower concentrations of bupivacaine for epidural analgesia compared to those who underwent cesarean sections, suggesting that higher local anesthetic needs may indicate more intense pain due to dystocia.

The findings imply that women experiencing dystocia during labor require more local anesthetic, which could influence the relationship between epidural analgesia and labor progression, highlighting the importance of pain management strategies in labor.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Local anesthetic requirements are greater in dystocia than in normal labor. Panni, MK., Segal, S.[2022]

Viscous lidocaine can pose a high risk of overdose in pediatric patients due to their altered pharmacokinetics, making doses safe for adults potentially toxic for children.

Benzocaine is recommended as a safer alternative for treating painful mouth lesions in children, as it has a lower incidence of side effects, but if lidocaine must be used, clear and specific dosing instructions should be provided to parents.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Lidocaine overdose: another preventable case? Gonzalez del Rey, J., Wason, S., Druckenbrod, RW.[2019]

The needle-free powder lidocaine delivery system provided significantly better pain relief compared to a sham placebo in pediatric patients undergoing venipuncture, as shown by lower pain scores on the Wong-Baker FACES scale (P = 0.0022).

The treatment was well tolerated with only minor side effects, such as erythema and petechiae, and no serious adverse events were reported, indicating it is a safe option for providing analgesia in children.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Safety and Efficacy of a Needle-free Powder Lidocaine Delivery System in Pediatric Patients Undergoing Venipuncture or Peripheral Venous Cannulation: Randomized Double-blind COMFORT-004 Trial. Schmitz, ML., Zempsky, WT., Meyer, JM.[2018]

Lidocaine hydrochloride is the most commonly used anesthetic in dermatology, and adverse reactions are very rare, primarily consisting of vasovagal responses and local effects like bruising and swelling.

This report highlights an extremely rare case of a true type I hypersensitivity allergy to lidocaine, which is believed to account for only 1% of all adverse reactions to this anesthetic.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Case reports: type I hypersensitivity to lidocaine. Haugen, RN., Brown, CW.[2013]

In a study of 23 samples of a lidocaine and phenylephrine topical solution, only 3 samples showed bacterial contamination, indicating a low risk of infection when using a modified application technique.

The modified technique, which involves keeping the spray nozzle pressed while withdrawing it from the patient, suggests that this topical solution could be safely used as a multi-use spray, potentially reducing costs without increasing infection risk.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Single-use lidocaine hydrochloride 5 per cent w/v and phenylephrine hydrochloride 0.5 per cent w/v topical spray; can it now be employed as a multi-use atomiser? Jog, M., Zudovaite, I., O'Dwyer, M., et al.[2020]

A case study highlighted a reproducible anaphylactic reaction to lidocaine hydrochloride, a common local anesthetic used in surgeries, emphasizing the need for caution in patients with potential allergies.

Early intervention with epinephrine, oxygen, and intravenous fluids effectively relieved the symptoms, underscoring the importance of prompt treatment in allergic reactions and the necessity of sensitivity testing before using lidocaine.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Anaphylactic reaction to lidocaine. Kennedy, KS., Cave, RH.[2022]

In a study involving 570 pregnant women undergoing amniocentesis, Xylocaine spray significantly reduced pain scores during the procedure compared to both a placebo and a control group, with median pain scores of 2.3, 3.3, and 2.8 respectively (p < 0.001).

Despite the reduction in pain during the procedure, the pain scores 30 minutes after the procedure were similar across all groups, suggesting that while Xylocaine is effective for immediate pain relief, the overall clinical significance may be limited due to the mild and short-lived nature of discomfort associated with amniocentesis.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effect of Xylocaine spray for analgesia during amniocentesis: a randomized controlled trial. Homkrun, P., Tongsong, T., Srisupundit, K.[2020]

Chloroprocaine provided a significantly faster onset of labor analgesia compared to lidocaine, with parturients receiving 1.5% chloroprocaine achieving adequate analgesia in an average of 7 minutes versus 12 minutes for those receiving lidocaine.

The study suggests that 6 mL of 1.5% chloroprocaine is the optimal regimen for labor analgesia, as it resulted in lower pain scores and higher maternal satisfaction without increasing adverse effects compared to both lidocaine and a lower concentration of chloroprocaine.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

A Randomized Clinical Trial Comparing Different Concentrations of Chloroprocaine with Lidocaine for Activating Epidural Analgesia During Labor. Zhu, HJ., He, Y., Wang, SY., et al.[2022]

Over the past 20 years, there has been a significant increase in the variety of topical anesthetics available for preventing neonatal pain, moving beyond just lidocaine injections to include creams, gels, and heat-activated patches.

While lidocaine injections are still commonly used for painful procedures in newborns, this review highlights the need for practical information on newer topical anesthetic options to improve pain management in neonates.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Topical anesthesia in neonates: clinical practices and practical considerations. Lehr, VT., Taddio, A.[2007]

References

1. United States pubmed.ncbi.nlm.nih.gov

Epidural test dose: lidocaine 100 mg, not chloroprocaine, is a symptomatic marker of i.v. injection in labouring parturients. [2018]

2. Lebanon pubmed.ncbi.nlm.nih.gov

Low concentration lidocaine (0.5%) bolus epidurally can initiate fast-onset, effective and safe analgesia for early stage labor. [2014]

3. United States pubmed.ncbi.nlm.nih.gov

Determination of the minimum local analgesic concentrations of epidural bupivacaine and lidocaine in labor. [2022]

4. England pubmed.ncbi.nlm.nih.gov

Topical lidocaine-prilocaine cream versus lidocaine infiltration for pain relief during repair of perineal tears after vaginal delivery: randomized clinical trial. [2019]

5. United States pubmed.ncbi.nlm.nih.gov

Local anesthetic requirements are greater in dystocia than in normal labor. [2022]

6. United States pubmed.ncbi.nlm.nih.gov

Lidocaine overdose: another preventable case? [2019]

7. United States pubmed.ncbi.nlm.nih.gov

Safety and Efficacy of a Needle-free Powder Lidocaine Delivery System in Pediatric Patients Undergoing Venipuncture or Peripheral Venous Cannulation: Randomized Double-blind COMFORT-004 Trial. [2018]

8. United States pubmed.ncbi.nlm.nih.gov

Case reports: type I hypersensitivity to lidocaine. [2013]

9. England pubmed.ncbi.nlm.nih.gov

Single-use lidocaine hydrochloride 5 per cent w/v and phenylephrine hydrochloride 0.5 per cent w/v topical spray; can it now be employed as a multi-use atomiser? [2020]

10. United States pubmed.ncbi.nlm.nih.gov

Anaphylactic reaction to lidocaine. [2022]

11. England pubmed.ncbi.nlm.nih.gov

Effect of Xylocaine spray for analgesia during amniocentesis: a randomized controlled trial. [2020]

12. New Zealand pubmed.ncbi.nlm.nih.gov

A Randomized Clinical Trial Comparing Different Concentrations of Chloroprocaine with Lidocaine for Activating Epidural Analgesia During Labor. [2022]

13. United States pubmed.ncbi.nlm.nih.gov

Topical anesthesia in neonates: clinical practices and practical considerations. [2007]