Epinephrine, absorption, and local anaesthetic systemic toxicity: insights from continuous fascial block pharmacokinetic models.

Fascial plane blocks have become increasingly popular owing to their technical ease and inclusion in postoperative analgesia guidelines, although uncertainties about their mechanisms and safety remain. A recent study of the impact of epinephrine on levobupivacaine pharmacokinetics in continuous fascial plane blocks proposes a potential safe dosing threshold and highlights the role of epinephrine in reducing systemic absorption. The study presents promising findings that advance our understanding of local anaesthetic pharmacokinetics in fascial blocks while raising important questions about drug absorption, patient-specific risk factors for local anaesthetic systemic toxicity, and the incompletely understood microanatomy of fascial tissues.