From the Guidelines
The least cardiotoxic local anesthetics are ropivacaine and levobupivacaine, with ropivacaine having approximately 40% less cardiotoxicity than bupivacaine, and levobupivacaine having about 30% less cardiotoxicity than bupivacaine. These agents are preferred when cardiac safety is a concern, particularly in patients with cardiovascular disease or when large volumes of anesthetic are required. Both medications are amide-type local anesthetics that have been specifically developed to reduce the cardiac risks associated with older agents like bupivacaine.
Key Characteristics of Ropivacaine and Levobupivacaine
- Ropivacaine has a maximum dose of 3 mg/kg, and levobupivacaine has a maximum dose of 2.5-3 mg/kg, as indicated in the study 1.
- The reduced cardiotoxicity of these agents is due to their decreased affinity for cardiac sodium channels and more rapid dissociation from these channels compared to bupivacaine.
- These agents cause less depression of cardiac conduction, less negative inotropy, and have a higher threshold for inducing ventricular arrhythmias.
Clinical Use
- Ropivacaine and levobupivacaine are safer options for epidural anesthesia, peripheral nerve blocks, and other procedures requiring significant local anesthetic volumes, especially in patients with cardiac risk factors.
- When using these medications, standard dosing guidelines should still be followed, and the maximum allowable safe dosage should be calculated before administration, as recommended in the study 1.
- The use of these agents can help minimize the risk of cardiotoxicity and ensure a safer outcome for patients, as supported by the study 1.
From the Research
Least Cardiotoxic Local Anesthetics
The least cardiotoxic local anesthetics are a subject of interest in the medical field, with various studies comparing the cardiotoxicity of different local anesthetics.
- Ropivacaine and levobupivacaine are considered to be less cardiotoxic than bupivacaine, with studies showing that they have a lower risk of cardiovascular toxicity 2, 3, 4, 5, 6.
- A study comparing the electrocardiographic cardiotoxic effects of racemic bupivacaine, levobupivacaine, and ropivacaine in anesthetized swine found that the lethal doses for levobupivacaine and ropivacaine were significantly higher than for bupivacaine 6.
- The cardiotoxicity potency ratios for the three anesthetics based on lethal dose were 2.1:1.2:1 for bupivacaine, levobupivacaine, and ropivacaine, respectively 6.
- Another study found that ropivacaine has a greater margin of safety than levobupivacaine, with fewer cardiotoxic effects 2.
- Levobupivacaine has been shown to have a lower risk of cardiovascular and CNS toxicity than bupivacaine in animal studies 3.
- Ropivacaine and levobupivacaine have been developed as alternatives to bupivacaine, with the goal of reducing the risk of systemic toxicity related to overdosing or unintended intravascular injection 4, 5.
Comparison of Local Anesthetics
The following local anesthetics have been compared in terms of their cardiotoxicity:
- Bupivacaine: considered to be more cardiotoxic than ropivacaine and levobupivacaine 2, 3, 4, 5, 6.
- Levobupivacaine: considered to be less cardiotoxic than bupivacaine, with a lower risk of cardiovascular toxicity 3, 6.
- Ropivacaine: considered to be less cardiotoxic than bupivacaine, with a greater margin of safety than levobupivacaine 2, 6.