Background : Video laryngoscopes such as the McGRATH^® MAC with X blade^TM (Xb) are reportedly effective in cases of tracheal intubation for difficult airway scenarios. However, the intubation time is strongly dependent on familiarity with the device. The purpose of this study was to investigate the minimum number of training experiences required to perform video laryngoscopy using Xb successfully in less than 30 seconds in a mannequin model.

  Methods : This study was conducted in 7 participants with less than 100 intubation experiences (group L) and in 10 participants with 100 to 200 intubation experiences (group H). Each participant was asked to perform a total of 10 video laryngoscopy procedures, taking turns one at a time, on a mannequin with a limited mouth opening (20 mm) and no back bending of the head using Xb. Video laryngoscopy was considered to have failed if more than 30 seconds were required or the maxillary anterior teeth were displaced. The success rate of video laryngoscopy and the time required to obtain an optimal view of the larynx were recorded. A two-way repeated measures analysis of variance using the linear mixed model and the Bonferroni test were used. A p value less than 0.05 was considered statistically significant.

  Results : A two-way repeated measures analysis of variance showed no interaction between the groups and the number of successful attempts or the time required to obtain an optimal view of the larynx. Four participants failed their first attempt, while all the participants succeeded at their nineth attempt. The time required to obtain an optimal view of the larynx became significantly faster at the seventh attempt and thereafter.

  Conclusions : Practice using a mannequin model successfully reduced the video laryngoscopy time. All the participants were able to perform video laryngoscopy successfully at their ninth attempt.

  We report the case of a 61-year-old woman whose severe neuropathic pain, caused by the extraction of the right maxillary lateral incisor, temporarily disappeared for seven months because of the development of tongue cancer. The patient’s right maxillary lateral incisor had been extracted because of a suspected tooth fracture 5 months prior to her first visit. After the extraction, she began to feel a tingling pain in the area of the tooth extraction site. Although the extraction site had healed well, she visited several dentists because of the pain but a cause could not be identified. Diclofenac sodium and over-the-counter analgesics were completely ineffective, and carbamazepine, which was prescribed for suspected trigeminal neuralgia, was ineffective.

  At the time of the patient’s first visit to our hospital, her Visual Analogue Scale (VAS) result was 72/100 mm, and she complained of a tingling pain that lasted all day. No macroscopic abnormalities of the mucosa were visible, but allodynia was observed.

  The patient was diagnosed with neuropathic pain following tooth extraction. Stellate ganglion blocks (SGB), adenosine 5-triphosphate (ATP) infusion, and oral pregabalin were ineffective. Fortunately, topical capsaicin therapy and oral tramadol (300 mg/day) almost eliminated the pain.

  Seven years and seven months after the first visit, the patient suddenly developed tongue cancer near the right lateral incisor ; at this time, the neuropathic pain in the right maxillary lateral incisor disappeared.

  The onset of the cancer might have caused conditioned pain modulation (CPM), which is a diffuse noxious inhibitory controls (DNIC)-like phenomenon.

  The tongue cancer was resected, and the neuropathic pain in the maxillary gingiva remained absent for 7 months from the onset of the tongue cancer, but gradually reappeared thereafter. At present, the patient’s pain is being controlled using oral tramadol (300 mg/day) and oral pregabalin (150 mg/day).

  We report a patient with Ramsay Hunt syndrome in whom the infusion of adenosine triphosphate (ATP) significantly alleviated neuropathic pain developing as a result of herpes zoster in the trigeminal nerve region.

  The patient was a 74-year-old man who complained of severe pain in the third branch region of the left trigeminal nerve and auricle at the time of his first visit and who exhibited edematous erythema and blisters. Since peripheral facial nerve paralysis appeared 6 days after the initial diagnosis, the administration of a stellate ganglion block (SGB), near-infrared therapy, prednisolone (30 mg/day, gradually decreasing), and mecobalamin (1.5 mg/day) was initiated. Two weeks later, neuropathic pain appeared, so pregabalin (50 mg/day, gradually increasing to 450 mg/day) and amitriptyline (10 mg/day, gradually increasing to 60 mg/day) were additionally administered. After repeated SGB and near-infrared therapy, the facial nerve paralysis nearly disappeared, but the improvement in the neuropathic pain was insufficient.

  Therefore, the intravenous administration of magnesium sulfate hydrate and lidocaine hydrochloride was performed. Since the pain relief was temporary, ATP infusion (100 μg/kg/min) was subsequently performed. The ATP infusion resulted in continuous pain relief ; thereafter, a total of 4 ATP infusions were performed. The pain gradually decreased and ultimately disappeared completely.

  A patient with takotsubo cardiomyopathy (TCM) underwent an open reduction and internal fixation under general anesthesia for a mandibular fracture. The patient had no history of cardiac disease, and TCM was thought to have been triggered by a fracture of the articular process of the mandible. Although the exact causes of TCM are not fully elucidated, it is known to be a stress-induced cardiomyopathy. The prevalence of TCM is high among postmenopausal women. The patient presented with no characteristic chest symptoms on admission to the hospital. However, she was diagnosed as having TCM according to the Mayo Clinic criteria. Since no specific treatment for TCM exists, it is important to avoid stress to prevent deteriorating symptoms. During surgery, her heart rate was controlled to avoid tachycardia and adequate intravascular volume was maintained using the FloTrac System, which enables the evaluation of stroke volume variations and invasive arterial blood pressure measurements. The use of sevoflurane and remifentanil hydrochloride, both of which have low cardiac depression effects and are easily adjustable, ensured good anesthetic management. The patient was carefully monitored and managed during the perioperative period to avoid the recurrence of TCM.