Lipid emulsion therapy of local anesthetic systemic toxicity due to dental anesthesia

Abstract

Local anesthetic systemic toxicity (LAST) refers to the complication affecting the central nervous system (CNS) and cardiovascular system (CVS) due to the overdose of local anesthesia. Its reported prevalence is 0.27/1000, and the representative symptoms range from dizziness to unconsciousness in the CNS and from arrhythmias to cardiac arrest in the CVS. Predisposing factors of LAST include extremes of age, pregnancy, renal disease, cardiac disease, hepatic dysfunction, and drug-associated factors. To prevent the LAST, it is necessary to recognize the risk factors for each patient, choose a safe drug and dose of local anesthesia, use vasoconstrictor , confirm aspiration and use incremental injection techniques. According to the treatment guidelines for LAST, immediate application of lipid emulsion plays an important role. Although lipid emulsion is commonly used for parenteral nutrition, it has recently been widely used as a non-specific antidote for various types of drug toxicity, such as LAST treatment. According to the recently published guidelines, 20% lipid emulsion is to be intravenously injected at 1.5 mL/kg. After bolus injection, 15 mL/kg/h of lipid emulsion is to be continuously injected for LAST. However, caution must be observed for >1000 mL of injection, which is the maximum dose. We reviewed the incidence, mechanism, prevention, and treatment guidelines, and a serious complication of LAST occurring due to dental anesthesia. Furthermore, we introduced lipid emulsion that has recently been in the spotlight as the therapeutic strategy for LAST.

Mechanisms and Efficacy of Intravenous Lipid Emulsion Treatment for Systemic Toxicity From Local Anesthetics

“…In dental uses, lidocaine accounts for the majority of LAST experiences, perhaps because lidocaine is used very frequently in dental procedures. It is unlikely that lidocaine is more toxic than bupivacaine ( 14 ). However, the use of bupivacaine in obstetrics is higher, and bupivacaine crosses placental barrier and so threatens the safety of the mother and the baby.…”

Mechanism of fat emulsion-mediated PTEN-PI3K-AKT signaling pathway on neurotoxicity of Bupivacaine

“…The cardiac function of the heart can be directly affected by fat, and inhibiting the oxidative metabolism of fatty acids will inhibit the cardiotoxic reaction caused by Bupivacaine. The fat emulsion can increase the concentration of fatty acids in cardiomyocytes and improve cardiac muscle strength (18). The inhibition of Bupivacaine on sodium channel current can be inhibited by free fatty acids, and fat emulsion can improve the metabolism of cardioid mitochondria and reduce the inhibition of Bupivacaine on intima carnitine lipoyltransferase (19).…”