Comparison of the Myotoxic Effects of Levobupivacaine, Bupivacaine, and Ropivacaine: An Electron Microscopic Study

Abstract

The aim of this study was to investigate the myotoxic effects of bupivacaine, ropivacaine, and levobupivacaine which were applied intramuscularly to rat skeletal muscle. Forty Wistar-Albino rats were divided into four groups. In the study, .5% bupivacaine (Group B), .5% ropivacaine (Group R), .5% levobupivacaine (Group L), or .9% normal saline (Group SF) was applied intramuscularly to the right gastrocnemius muscle of rats. The rats in each group were sacrificed on the second day after injection. Sections of muscle samples were stained with hematoxylin-eosin for light microscopic investigation and prepared for the evaluation of ultrastructural changes in the subcellular level with transmission electron microscopy. All three local anesthetic agents caused qualitatively similar skeletal muscle damage. The most observed muscle damage was in Group B, muscle damage of Group R was less than that of Group B, and the least damage was seen in Group L quantitatively. Electron microscopic examination of each group that caused cellular damage was qualitatively similar. The most subcellular damage was observed in the group receiving bupivacaine, less was seen in the ropivacaine group, and the least was observed in the levobupivacaine group. The results indicated that bupivacaine caused more myotoxic damage than the other two agents in the skeletal muscle of rats and that levobupivacaine caused less myotoxic damage than both bupivacaine and ropivacaine at the cell and tissue levels.

Low-level laser therapy (LLLT) accelerates the sternomastoid muscle regeneration process after myonecrosis due to bupivacaine

“…This framework is observed ultrastructurally through disorganized myofibrils, a fragmented and discontinued Z line, abundant central nuclei, the presence of inflammatory cells, and areas of fibrosis and edema. Due to the excessive accumulation of Ca 2+ , there are alterations in the morphology and function of the mitochondria, which trigger inhibition of enzymatic activity and block the synthesis of ATPase, resulting in myonecrosis [58,59].…”

Local anaesthetic-induced myotoxicity in regional anaesthesia: a systematic review and empirical analysis

“…Regardless of concentration, the site of LA injection in muscle tissue became the site of a localised inflammatory response, 2,58,61,63 marked by aggregation of inflammatory cells, including neutrophils, lymphocytes, and macrophages. 2,22,26,51,52,60,61,63,72,74,81 Injections of low concentrations of any of bupivacaine, 61,63 mepivacaine, 2 lidocaine, 2,63 procaine, 2 ropivacaine, 58 and liposomal ropivacaine 58 into muscle tissue resulted in a purely inflammatory infiltrate that appeared between 24 h and 1 week 2,58,61,63 at the injection site. Similar inflammatory changes were observed with high concentrations of mepivacaine, 2 lidocaine, 2 and procaine.…”

“…11,12,16,19,22,46,54,55,59,61,67,68,72e74,78 Degeneration was more extensive with bupivacaine compared with ropivacaine and levobupivacaine. 57,60,69,70…”

“…I.M., 8,58e60,62,63 percutaneous, 61 s.c. 59 Bupivacaine 8,60,62,63 bupivacaine with triamcinolone, 62 levobupivacaine, 60 lidocaine, 61 mepivacaine, 59 procaine 62 procaine with triamcinolone, 62 ropivacaine, 8,58,60 liposomal ropivacaine 58 0 mM, 8,61,62 8.66 mM, 62 10.59 mM, 62 17.3 mM, 8,60,63 18.2 mM, 8,60 85.4 mM, 61 121.8 mM, 59 4.6e18.2 mM 58 100 ml, 60 0.1 ml, 8,58 0.5 ml, Major, 58,63 partial, 61,63 minimal, 60,62 NS 8,58,59 Continued Rats 16,59,64e67 Femoral nerve block, 65 I.M., 59 S.C., 16,59,66,67 sciatic nerve block 64 Bupivacaine, 16,64e66 lidocaine, 16 lidocaine with epinephrine, 67 mepivacaine, 16,…”

The Potential Protective Effects of 2-aminoethyl Diphenylborinate against Inner Ear Acoustic Trauma: Experimental Study Using Transmission and Scanning Electron Microscopy

“…Semi-thin sections of 700-800 nm were stained with toluidine blue. Thin sections (70-80 nm) were double stained by uranyl acetate and lead citrate [12] . Images were obtained using an FEI (Biotwin, Netherlands) TEM.…”