Understanding and treating Local Anesthetic Systemic Toxicity: narrative review

Local Anesthetic Systemic Toxicity (LAST) is a rare but life-threatening adverse event caused by accidental high plasma levels of local anesthetic (LA). Instant LAST manifests within minutes because of intravascular injection of large amounts of LA. Slow LAST occurs up to ≥ 30 min after LA injection due to either excessive local tissue absorption, or slowly increasing level from continuous infusions of LA. As plasma LA rises beyond safe levels, initial excitation occurs in both the central nervous and cardiovascular systems, followed by a profound depression. Although neurological presentation is most common, LAST often presents atypically, and the documented clinical variability demands that the practitioners must maintain high index of suspicion of possible LAST, whenever any unexplained physiological changes are noticed after administration of LA.
Risk of LAST depends mostly on the anesthetic techniques and the patient risk-factors such as extreme of ages, pregnancy and comorbidities. Prevention is the most important element to increase patient safety and avoid morbidity and mortality associated with LAST. Early recognition and intervention, including modified advanced cardiorespiratory support and intravenous 20% lipid emulsion, are the mainstays of treatment.
The scope of this narrative review is to address LAST, discuss its mechanisms, and provide an update on prevention, diagnosis, and management of local anesthetic systemic toxicity.

Per continuare la lettura gli abbonati possono scaricare l’allegato