Use of the Microcuff® During General Anesthesia for Patients With Scoliosis.

Scoliosis may often be associated with a variety of cardiovascular and respiratory conditions or diseases, and depending on the severity of the spinal deformity, it may also complicate anesthetic management because of the difficulty of neck extension and tracheal deformity. Therefore, patients with scoliosis may require careful perioperative anesthetic considerations. A 14-year-old girl was scheduled to undergo extractions and restorative treatment for dental caries under general anesthesia. Her medical history was significant for intellectual disability and autism as well as previously undiagnosed scoliosis. After fixation of a 6.0 Portex® endotracheal tube (ETT), percutaneous oxygen saturation (SpO2) decreased to 93%, peak airway pressures increased, and unilateral lung ventilation was noted. Inadvertent mainstem bronchial intubation was immediately suspected, prompting removal of the Portex ETT and reintubation with a shorter 6.0 Microcuff® ETT. The dental treatment was completed successfully without further incident. Assessment of the ETTs used intraoperatively led to the determination that the distance from the glottis to the carina was considerably shorter than normal for this patient. It was speculated that the Microcuff ETT may be optimal for anesthetic management of scoliosis patients because of its shorter lengths compared with other style ETTs, which may reduce the risk of bronchial intubation in such cases.

The effectiveness of educational methods for cricothyroid membrane identification by dental students: A prospective study using neck photographs and tracheotomy trainers.

The purpose of this study was to evaluate the accurate identification of the cricothyroid membrane (CTM) by fifth grade dental students, before undergoing the relevant anesthesiology practicum. Moreover, we aimed to determine the educational effectiveness of the cricothyrotomy practicum in anesthesiology. Before the lecture and without prior notification, 119 students were provided with a photograph of a man's neck and instructed to attach a blue sticker to the cricothyrotomy puncture site and to a palpable tracheotomy trainer, after applying sufficient palpation. After this, students attended a 60-min lecture on the emergency airway management method. Two and 16 days after the lecture and practicum, students were presented with a new neck photograph and the tracheotomy trainer and asked again to place stickers (red stickers: at 2 days; green stickers: at 16 days) on the cricothyrotomy penetration site. The data were analyzed with an image processing software, by superimposing the 119 stickers on the neck photographs and tracheotomy trainers, to visually examine the accuracy of CTM identification. The rate of correct sticker placement in the neck photographs was 41.2% before the lecture, 80.7% 2 days after the lecture, and 77.3% 16 days after the lecture (before vs. 2 and 16 days after, p value < 0.01). For the tracheotomy trainer, the rate was 36.1% before the lecture, 97.5% 2 days after the lecture, and 94.1% 16 days after the lecture (before vs. 2 and 16 days after, p value < 0.01). Furthermore, the proportion of students with mistakes above and below the CTM was higher than that of students with mistakes to the right or left. In conclusion, the rate of accurate CTM identification among dental students was low before they underwent the relevant practicum, but most students were able to identify the CTM accurately after the lecture and practicum in a small class.

Effect of Topical Anesthesia Using an Adhesive Patch and Anesthetic Solution.

We analyzed trigeminal somatosensory evoked potentials (TSEP) to the alveolar mucosa to investigate the efficacy of an amide local anesthetic, 2% lidocaine hydrochloride with 12.5 µg/mL epinephrine (Lido treatment) as a topical anesthetic. Eighteen consenting healthy adult volunteers were enrolled. A volume of 0.06 mL of Lido, 0.06 g of 20% benzocaine, or 0.06 mL of physiological saline (control) was instilled onto a hemostatic adhesive patch, which was then applied to the alveolar mucosa at the maxillary right canine for 5 minutes. An electrical stimulus approximately 5 times that of the sensory threshold was applied using a surface stimulation electrode. The trigeminal somatosensory evoked potential was recorded immediately, 5 minutes, and 10 minutes after removal of the patch. Positive P125 and P310 peaks and negative N100 and N340 peaks were observed as a result of the electrical stimulation. A significant decrease in the percentage change in amplitude of N100-P125 was observed in the Lido treatment immediately, 5 minutes, and 10 minutes after patch removal. In the Lido treatment, trigeminal somatosensory evoked potential amplitude at N100-P125 decreased significantly, suggesting that topical anesthesia produced by an amide local anesthetic may have a topical anesthetic effect as potent as that produced by an ester local anesthetic.