0000000000309085
AUTHOR
Xavier Sala-blanch
ESRA19-0618 Vulnerability of different nerves to intrafascicular injection with different needle bevel types and needle angles: a mathematical model
Background and aims Intrafascicular injection of a local anesthetic, its toxicity, and direct needle trauma to nerve tissue are generally considered the primary reasons for nerve injury after intraneural injection. We hypothesize that the only way that the local anesthetic can enter the fascicle is if at least 80% of the distal needle orifice is inside the fascicle. the aim of this study was to calculate the theoretical vulnerability of nerve fascicles given their actual sizes and that of different needle openings. Methods We superimposed microscopic images of two routinely used nerve block needles (a 22-G, 15 ‘StimuplexOD’ needleand a 22-G, 30 ‘StimuplexOUltra 360O’ needle) over microscopi…
Blocs nerveux périphériques, paresthésies et injections intraneurales
Resume Les fibres nerveuses, myelinisees ou non, sont disposees en faisceaux et entourees de plusieurs membranes l’endonerve, l’epinerve et la perinerve. La transmission de l’influx nerveux se fait de facon saltatoire d’un noeud de Ranvier a l’autre sur les fibres myelinisees et de facon continue sur les fibres non myelinisees. La compression ou le traumatisme d’un nerf produit une rafale de potentiels d’action que le patient interprete comme une paresthesie. Ce phenomene persiste tant que dure la lesion axonale. Les aiguilles a biseau court penetrent moins souvent la perinerve mais donne des lesions plus importantes dans ce cas. L’echoguidage montre que des injections intraneurales interfa…
Vulnerability of different nerves to intrafascicular injection by different needle types and at different approach angles: a mathematical model
Background and objectivesWe assume that intrafascicular spread of a solution can only occur if a large enough portion of the distal needle orifice is placed inside the fascicle. Our aim is to present and evaluate a mathematical model that can calculate the theoretical vulnerability of fascicles, analyzing the degree of occupancy of the needle orifice in fascicular tissue by performing simulations of multiple positions that a needle orifice can take inside a cross-sectional nerve area.MethodsWe superimposed microscopic images of two routinely used nerve block needles (22-gauge, 15° needle and 22-gauge, 30° needle) over the microscopic images of cross-sections of four nerve types photographed…