Clinical Study Of The Applicat Ion Of He Video Laryngoscope And Macintosh Laryngoscope In Simulated Difficult Airway

ObjectiveIn this study, to evaluate feasibility and effectiveness of ordinary airway becoming difficult airway through using inflatable neck immobilization device. And to evaluate efficacy and safety of intubation by observation He video laryngoscope used in patients with simulated difficult airwayMethods1. The pre-test,100female volunteers, recording age, body mass index (BMI).use improved inflatable cervical collar measured on volunteers,when no discomfort, record its maximum inflation volume, and calculate the mean pressure value.2. Choose60patients from May2012to January2013requiring endotracheal intubation general anesthesia and gynecological laparoscopy, The60patients of ASA Ⅰ and Ⅱ, aged20-60yr, BMI18～30kg/m2,Get patient consent and signe informed consent preoperative, Do airway assessment visit before surgery the day before surgery, and record mouth opening. All used inhalational general anesthesia.Excluse patients with difficult mask ventilation or foreseeable difficulties endotracheal intubation, another history of difficult intubation were also excluded. Randomly divide into2groups:H group (He video laryngoscopes group) and M (Macintosh laryngoscope group)(n=30). Use inhalational general anesthesia, after the patient enters the operating room connecting the monitor. After supine rest, inhalation anesthesia using neck immobilization device inflatabled with the previous pre-test pressure to simulate difficult airway, measure mouth degrees.3. laryngoscope intubationUsing the Macintosh laryngoscope and He video laryngoscopes respectively in two group, and recording Cormack-Lehane laryngeal criteria classification. Each patient was allowed up to twice the cannula in ensure good ventilation and pulse oximetry or when the anesthesiologist considere inserted try once is dangerous to the patient, the neck holder will have to be removed, then intubate using a direct laryngoscope. Record MAPandHR of that before intubation, best the glottis revealed, the immediatel when endotracheal tube inserted and when lmin,2min,3min after the endotracheal tube inserted and postoperative sore throat discomfort and traumaResults1Mouth opening was significantly smaller in patients when used inflatable cervical collar analog difficult airway (P<0.05)2. Glottis exposed graded in simulated difficult airway patients (Cormack-Lehane standard), compared to the Macintosh laryngoscope, He video laryngoscopes may reduce the glottal grade level, He video laryngoscopes provide better exposure of the glottis.3. Rate of success intubation in H group is greater than M group. Time of intubation was no significant difference between the two groups.4. Hemodynamic fluctuation in that times best revealed the glottis, immediate when the endotracheal tube inserted, lmin after endotracheal tube insertion, Fluctuation in H group is less than M group, with statistical significance (P<0.05)5. Eleven cases (36.7%) patients had a sore throat after extubation in M group, and three (10%) in H group, with statistical significance P<0.05Four (13.3%) patients in M group, with endotracheal tube with blood, was significantly higher than the zero cases in H group (P<0.05), pain and pharyngeal mucosa bleeding was mitigation and rehabilitation in the first two days after. Patients of two groups had no other significant adverse events.ConelusionsSimulating difficult airway with cervical fixation device is safe and effective; the HC video laryngoscope used in simulated difficult airway compared with the Macintosh laryngoscope, can reduce the glottic exposure (Cormack-Lehane standard), improve vision, raise the success rate of intubation, reduce influence on hemodynamics and throat complications.