From the Guidelines
Safety of Dental Blocks with Bupivacaine in Pregnancy
The use of dental blocks with bupivacaine (Marcaine) in pregnancy is considered safe when administered in recommended doses 1. A typical dose of 0.5% bupivacaine, not exceeding 2.5 mg/kg or 90 mg per procedure, is generally well-tolerated.
- Key Considerations:
- Bupivacaine is classified as a Category C drug by the US Food and Drug Administration, meaning that while animal reproduction studies have shown an adverse effect, there are no controlled studies in women, or studies in women and animals are not available 1.
- The duration of action for bupivacaine is approximately 6-12 hours, and it is essential to avoid excessive doses and prolonged use to minimize potential fetal exposure and risk of maternal toxicity.
- Important Factors:
- The addition of epinephrine to local anesthesia, such as bupivacaine, may be safe in small amounts for use in pregnant women, but clinicians should exercise caution and consider the risk-benefit ratio 1.
- The safety of bupivacaine in pregnancy has been demonstrated in dental surgery, but it is crucial to follow recommended dosages and guidelines to minimize potential risks 1.
From the FDA Drug Label
There are no adequate and well-controlled studies in pregnant women. Bupivacaine hydrochloride should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus Bupivacaine hydrochloride produced developmental toxicity when administered subcutaneously to pregnant rats and rabbits at clinically relevant doses.
The use of bupivacaine (Marcaine) for dental blocks during pregnancy is not supported by adequate and well-controlled studies. Bupivacaine should only be used during pregnancy if the potential benefit justifies the potential risk to the fetus. Key considerations include:
- Developmental toxicity: Bupivacaine produced developmental toxicity in pregnant rats and rabbits at clinically relevant doses.
- Risk vs. benefit: The decision to use bupivacaine during pregnancy should be made on a case-by-case basis, weighing the potential benefits against the potential risks to the fetus 2.
From the Research
Safety of Bupivacaine in Pregnancy
- The use of bupivacaine (Marcaine) in obstetrics for epidural analgesia has been studied, and it has been found to have a good sensory block with minimal side effects on the mother and newborn infant 3.
- A study on spinal anesthesia for elective cesarean section using different doses of hyperbaric bupivacaine associated with morphine and clonidine found no significant maternal and fetal repercussions 4.
- However, the provided studies do not directly address the safety of dental blocks with bupivacaine during pregnancy.
- A study on the effects of buprenorphine added to bupivacaine infraorbital nerve blocks in dogs found no adverse cardiorespiratory effects, but this study is not directly relevant to human pregnancy 5.
- Another study on reversing the effects of 0.5% bupivacaine using phentolamine mesylate found it to be safe and effective, but again, this study is not directly related to pregnancy 6.
- A review of levobupivacaine, a local anesthetic similar to bupivacaine, found it to have a lower risk of cardiovascular and CNS toxicity, but this study does not specifically address dental blocks during pregnancy 7.
Key Findings
- Bupivacaine has been found to be safe for use in obstetrics, but its safety for dental blocks during pregnancy is not well-studied.
- The available studies do not provide conclusive evidence on the safety of dental blocks with bupivacaine during pregnancy.
- More research is needed to determine the safety of dental blocks with bupivacaine during pregnancy.