Shin Chi Won, Son Won-Gyun, Jang Min, Kim Hyunseok, Han Hyungjoo, Cha Jeesoo, Lee Inhyung
Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea.
Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea; Ian Animal Diagnostic Imaging Center, Seoul, Republic of Korea.
Vet Anaesth Analg. 2018 Jan;45(1):13-21. doi: 10.1016/j.vaa.2017.10.002. Epub 2017 Nov 7.
To determine the optimal endotracheal tube size in Beagle dogs using thoracic radiography.
Prospective, randomized, crossover experimental study.
A total of eight healthy adult Beagle dogs.
Lateral thoracic radiographs were used to measure the internal tracheal diameter at the thoracic inlet. This measurement was multiplied by 60, 70 and 80% to determine the outer diameter of the endotracheal tube for each dog. In each treatment, medetomidine (5 μg kg) was administered intravenously (IV) for premedication. Anesthesia was induced with alfaxalone (2 mg kg) IV and maintained with isoflurane. After induction of anesthesia, the resistance to passage of the endotracheal tube through the trachea was scored by a single anesthesiologist. Air leak pressures (P) were measured at intracuff pressures (P) of 20 and 25 mmHg (27 and 34 cmHO). The results were analyzed using Friedman tests and repeated measures anova.
There were statistically significant increases in resistance as the endotracheal tube size increased (p = 0.003). When P was 20 mmHg, mean P for the 60, 70 and 80% treatments were 9.7 ± 6.7, 16.2 ± 4.2 and 17.4 ± 3.9 cmHO, respectively, but no significant differences were found. When P was 25 mmHg, mean P for the 60, 70 and 80% treatments were 10.6 ± 8.5, 19.7 ± 4.9 and 20.8 ± 3.6 cmHO, respectively, and statistically significant increases were found between treatments 60 and 70% (p = 0.011) and between treatments 60 and 80% (p = 0.020). Three dogs in the 80% treatment had bloody mucus on the endotracheal tube cuff after extubation.
Results based on resistance to insertion of the endotracheal tube and the ability to achieve an air-tight seal suggest that an appropriately sized endotracheal tube for Beagle dogs is 70% of the internal tracheal diameter measured on thoracic radiography.
通过胸部X光摄影确定比格犬的最佳气管内导管尺寸。
前瞻性、随机、交叉实验研究。
总共8只健康成年比格犬。
使用胸部侧位X光片测量胸廓入口处气管内径。将该测量值分别乘以60%、70%和80%，以确定每只犬的气管内导管外径。在每次治疗中，静脉注射美托咪定（5μg/kg）进行术前用药。用阿法沙龙（2mg/kg）静脉诱导麻醉，并用异氟烷维持麻醉。麻醉诱导后，由一名麻醉医生对比气管内导管通过气管的阻力进行评分。在气囊内压力为20和25mmHg（27和34cmH₂O）时测量漏气压力（P）。结果采用Friedman检验和重复测量方差分析进行分析。
随着气管内导管尺寸的增加，阻力有统计学意义的增加（p = 0.003）。当P为20mmHg时，60%、70%和80%治疗组的平均P分别为9.7±6.7、16.2±4.2和17.4±3.9cmH₂O，但未发现显著差异。当P为25mmHg时，60%、70%和80%治疗组的平均P分别为10.6±8.5、19.7±4.9和20.8±3.6cmH₂O，在60%和70%治疗组之间（p = 0.011）以及60%和80%治疗组之间（p = 0.020）发现有统计学意义的增加。80%治疗组中有3只犬在拔管后气管内导管气囊上有血性黏液。
基于气管内导管插入阻力和实现气密密封能力的结果表明，比格犬合适尺寸的气管内导管为胸部X光片测量的气管内径的70%。
