Comparative Study of TOF-Cuff, a New Neuromuscular Blockade Monitor, and TOF-Watch, an Acceleromyography.

Train-of-four ratios were recorded to assess the agreement between the TOF-Cuff and TOF-Watch, and residual paresis was assessed to evaluate the clinical utility of TOF-Cuff. Train-of-four ratios were evaluated using Lin concordance correlation coefficient and Bland-Altman analyses. Measured train-of-four ratios demonstrated high accuracy and precision over the entire range of train-of-four ratios. Although precision and Lin concordance correlation coefficients decreased with train-of-four ratios >0.7, none of the patients showed signs of residual paresis. Because TOF-Cuff underestimated train-of-four ratios in the recovery period, the clinical safety of train-of-four ratios >0.9 indicated by TOF-Cuff is unclear; the issue of residual paresis requires future research that rigorously evaluates outcomes.

[McGRATH® MAC Is Useful to Learn Tracheal Intubation Using a Macintosh Laryngoscope].

BACKGROUND: Learning tracheal intubation using a Macintosh laryngoscope (McL) is important although video laryngoscope is becoming popular. The purpose of this study was to compare the usefulness as a training device for intubation technique using McL with three devices; McGRATH® MAC (MAC), Airwayscope® (AWS) and McL. METHODS: In this prospective study, 60 nurses not experienced in tracheal intubation were randomly assigned to MAC, AWS, and McL groups (each group: n=20), and 10 times of practice using each device were carried out. We compared the intubation time using McL and the nurse's anatomical understanding of the larynx before and after the practice. RESULTS: The intubation time before the practice was comparable among the three groups, but the time after the practice was significantly shorter in the McL and MAC groups compared to the AWS group (P=0.001). The practice significantly improved anatomical understanding of the larynx in all groups (P<0.05), and in particular it was improved in the MAC and AWS groups compared with the McL group (P<0.001). CONCLUSIONS: The McGRATH® MAC may possess advantages compared to Airwayscope® and Macintosh laryngoscope as a training device for learning intubation technique using Macintosh laryngoscope and understanding anatomy of the larynx.

Cricothyrotomy for an Unexpected Cannot Intubate, Cannot Ventilate Situation for a Patient with Chronic Graft-Versus-Host Disease After Induction of General Anesthesia: A Case Report.

BACKGROUND Chronic graft-versus-host disease (GVHD) is a major complication of hematopoietic stem cell transplantations. Due to fibrotic changes, patients with GVHD are at risk for difficult airway management. We encountered a case of chronic GVHD that went into a "cannot intubate, cannot ventilate" (CICV) condition after induction of general anesthesia and was managed using cricothyrotomy. CASE REPORT A 45-year-old man with uncontrolled chronic GVHD developed pneumothorax of the right lung. Thoracoscopic dissection of the adhesions, closure of the pneumostomy, and drainage under general anesthesia were planned. In the preoperative airway assessment, we concluded that using a video laryngoscope or endotracheal fiber would be sufficient to intubate the patient after sedation and that airway management after the loss of consciousness would not be difficult. Therefore, general anesthesia was induced by rapid induction; however, the patient developed difficult mask ventilation. Intubation was attempted via a video laryngoscope or bronchofiber but failed. Ventilating using a supraglottic instrument was difficult. The patient was evaluated to have a CICV condition. Thereafter, because of a rapid decrease in oxygen saturation (SpO2) and bradycardia, a cricothyrotomy was performed. Subsequently, ventilation became adequate, SpO2 increased immediately and drastically, and respiration and circulatory dynamics recovered. CONCLUSIONS We believe that anesthesiologists should practice, prepare, and simulate airway emergencies that can be experienced during surgery. In this case, we recognized that skin sclerosis in the neck and chest could lead to CICV. It may be suitable for airway management of scleroderma-like patients to select conscious intubation with a bronchoscope as a first choice.