Mechanical strain to maxillary incisors during direct laryngoscopy

BMC Anesthesiology

Research Article

Mary Golinski¹  Lauryn R. Rochlen²  Elizabeth Jewell²  Milo Engoren³  Paul Begeman⁴  John M. Cavanaugh⁴  Matthew V. Diehl⁴  Sarah S. Sherman⁴ 

[1] Beaumont Graduate Program of Nurse Anesthesia, Oakland University, Rochester, MI, USA;Department of Anesthesiology, University of Michigan, Ann Arbor, MI, USA;Department of Anesthesiology, University of Michigan, Ann Arbor, MI, USA;Department of Anesthesiology, Mercy St. Vincent Medical Center, Toledo, OH, USA;Department of Biomedical Engineering, Wayne State University, Detroit, MI, USA;

关键词: Laryngoscopy;    Dental injury;    Strain;    Intubation;   

DOI  :  10.1186/s12871-017-0442-z

 received in 2017-07-09, accepted in 2017-10-31,  发布年份 2017

来源: Springer

【 摘 要 】

BackgroundWhile most Direct laryngoscopy leads to dental injury in 25–39% of cases. Dental injury occurs when the forces and impacts applied to the teeth exceed the ability of the structures to dissipate energy and stress. The purpose of this study was to measure strain, (which is the change produced in the length of the tooth by a force applied to the tooth) strain rate, and strain-time integral to the maxillary incisors and determine if they varied by experience, type of blade, or use of an alcohol protective pad (APP).MethodsA mannequin head designed to teach and test intubation was instrumented with eight single axis strain gauges placed on the four maxillary incisors: four on the facial or front surface of the incisors and four on the lingual or back, near the insertion of the incisor in the gums to measure bending strain as well as compression. Anesthesiology faculty, residents, and certified registered nurse anesthetists intubated with Macintosh and Miller blades with and without APP. Using strain-time curves, the maximum strain, strain rate, and strain time integral were calculated.ResultsAcross the 92 subjects, strain varied 8–12 fold between the 25th and 75th percentiles for all four techniques, but little by experience, while strain rate and strain integral varied 6–13 fold and 15–26 fold, respectively, for the same percentiles. Intubators who had high strain values with one blade tended to have high strains with the other blade with and without the APP (all pairwise correlation rho = 0.42–0.63).ConclusionsStrain varies widely by intubator and that the use of the APP reduces strain rate which may decrease the risk of or the severity of dental injury.

【 授权许可】

CC BY   
© The Author(s). 2017