操作台高度与气管插管视野的影响.pdf

Higher operating tables provide better laryngeal views for tracheal intubation Lu Rui British Journal of Anaesthesia112(4): 749–55 (2014) Background the quality of laryngeal view the discomfort of the anaesthetist during enodotracheal intubation Methods Methods 纳入标准：ASA I –III 排除标准：body mass index (BMI)＞30 aged＜18 or ＞ 85 y congenital or acquired airway abnormalities loose teeth or edentulous jaws increased risk of aspiration Methods The airway assessments A: inter-incisor distance B: thyromental distance A B A: 正常值3.5~5.6cm B: 成人通常大于6.5cm Methods The airway assessments C: neck circumference C: neck circumference ＜45cm Methods The airway assessments D: Mallampati classification MP Class I- Soft palate, tonsillar fauces, tonsillar pillars, and uvula MP Class II- Soft palate, tonsillar fauces, partial uvula MP Class III- Soft palate, base of uvula MP Class IV- Hard palate only MP III and MP IV are associated with greater likelihood of a difficult airway. Methods (Group N) nipple (Group X) xiphoid process (Group R) lowest rib margin (Group U) umbilicus Methods i.v. midazolam (0.03 mg/kg) 10 min before anaesthesia (Group N) nipple Routine monitoring(non-invasive arterial pressure Measurement, SpO2, electrocardiography) (Group X) xiphoid process The height of the operating table was adjusted (Group R) lowest rib margin pre-oxygenation (Group U) umbilicus anaesthesia was induced with i.v. propofol (1.5 mg/ kg) and alfentanil (0.01Mg/kg) i.v. rocuronium (0.6 mg/kg) a gradual increase of inspired sevoflurane to 6– 8 vol% Two minutes after rocuronium injection, tracheal intubation was performed under direct laryngoscopy Methods Outcome measures A. Cormack and Lehane criteria Grade 1, complete visualization of the vocal cords; Grade 2, visualization of the inferior portion of the glottis; Grade 3, visualization of only the epiglottis; Grade 4, non-visualization of the epiglottis Methods Methods Outcome measures B. assessment of wrist exertion during mask ventilation and joint strains. C. The degrees of task discomfort during mask ventilation or tracheal intubation were graded. 1=no discomfort, 2=mild discomfort, 3=moderate discomfort, 4=severe discomfort Results Results Results Limitations 1. It was not possible to blind anaesthetists to the relative table height. 2. Objective assessment of muscle strains, such as electromyography of the biceps or trapezius, and measurements of three-dimensional orientation were not performed. 3. In more obese anaesthetists, the umbilicus and lowest rib margin have an uncertain vertical relationship to one another 4. The laryngeal viewswere not captured using an endoscope so as to be graded by other blinded investigators. 5. The patient’s head and neck posture during laryngoscopy was neither controlled nor monitored.