Uticaj epinefrina i medetomidina na sistemsku resorpciju epiduralno primenjenog lidokaina kod anesteziranih svinja

Abstract

Epinephrine and alpha 2 agonist drugs are often used with epidural anesthesia to minimize local anesthetic systemic absorption, as well as to prolong the duration of the block. The aim of the current study was to determine by which extent epinephrine and medetomidine influenced lidocaine systemic absorption rate following epidural application. This was achieved by monitoring the serum lidocaine concentration in a porcine model. During general anesthesia, the first group received epidurally plane lidocaine, the second received lidocaine containing epinephrine (1 : 80.000), and the third lidocaine with medetomidine (15 μg/kg). Venous blood samples were taken before and 5, 10, 20, 30, 45, 60 and 90 minutes following epidural administration of the anesthetic. The effects of epinephrine and medetomidine were comparable. They both failed to cause a significant decrease in serum lidocaine concentration (p>0.05). In these settings we were unable to demonstrate a greater capacity of these two adrenergic agonists for reducing lidocaine systemic uptake and, accordingly, its systemic toxicity potential.

Epinefrin i alfa 2 agonisti se uvek koriste u epiduralnoj anesteziji da umanje sistemsku apsorpciju lokalnog anestetika i da produže trajanje epiduralnog bloka. U serumu svinja se određivala koncentracija lidokaina, stoga je cilj ove studije da se odredi do koje mere epinefrin i medetomidin utiču na sistemsku apsorpciju lidokaina nakon epiduralne primene. Tokom opšte anestezije prvoj grupi je epiduralno aplikovan lidokain, drugoj lidokain s epinefrinom (1: 80000), a trećoj lidokain sa medetomidinom (15 μg/ kg). Krv iz vene je uzorkovana pre, 5, 10, 20, 30, 45, 60 i 90 minuta nakon epiduralne primene anestetika. Poređeni su efekti epinefrina i medetomidina, ali ni jedan nije signifi kantno smanjio serumsku koncentraciju lidokaina (p>0,05). Ove kombinacije adrenergičnih agonista nisu smanjile sistemsku resorpciju lidokaina. U skladu s tim, potencijalno je moguća sistemska toksičnost lidokaina.