Successful reversal of remimazolam anesthesia in a "cannot intubate, can ventilate" situation: a case report.

BACKGROUND: Compared to other intravenous anesthetics, availability of a specific antagonist flumazenil is a clear advantage of remimazolam. We report a patient who could be rapidly woken up when laryngoscopy and tracheal intubation were unexpectedly difficult. CASE PRESENTATION: A 62-year-old man was scheduled to have resection of a small gingival tumor. Preoperative airway examination was unremarkable except for an omega-shaped epiglottis. Anesthesia was induced with remifentanil/remimazolam infusion and rocuronium. A small omega-shaped edematous epiglottis precluded identification of glottis. Consciousness and spontaneous ventilation were rapidly restored after administration of flumazenil and sugammadex. Tracheostomy was done under local anesthesia while the patient breathed spontaneously. CONCLUSIONS: Remimazolam can be a reasonable induction agent when there are concerns regarding airway management. Avoiding repeated airway manipulations is extremely important to prevent deterioration into a "cannot intubate, cannot ventilate (CICV)" emergency.

Coagulation assessment with thromboelastography during abdominal endovascular aneurysm repair in a patient with hemophilia A.

BACKGROUND: As both APTT and APTT-based coagulation method cannot distinguish heparin effect from intrinsic coagulation factor deficiency, we implemented thromboelastography (TEG) for the coagulation assessment in a patient with hemophilia A undergoing an endovascular surgery with heparinization. CASE PRESENTATION: A 68-year-old male with hemophilia A underwent endovascular aortic repair for abdominal aortic aneurism. TEG results showed recovery of coagulation time (R) in both kaolin assay (CK) and kaolin-heparinase assay (CKH) after factor VIII replacement before heparinization. Against our expectations, R-CKH was slightly prolonged (9.0 min) during heparinization. After the administration of protamine sulfate, R in both assays showed similar values within the normal ranges. CONCLUSIONS: The combination of CK and CKH assays could be useful to estimate factor VIII (FVIII) level when heparin concentration is low or without heparin; however, caution should be necessary for estimation of FVIII level by TEG under the effect of medium- or high-dose heparin.

Effect of availability of video laryngoscopy on the use of fiberoptic intubation in school-aged children with microtia.

BACKGROUND: With the increasing popularity of video laryngoscopy during intubation of pediatric patients with normal or difficult airways, fiberoptic-assisted tracheal intubation, traditionally considered the gold standard for difficult intubation, may become underused. AIM: We aimed to assess the use of airway management techniques before and after introduction of video laryngoscopy in a cohort of school-aged children with microtia, who are at increased risk of difficult intubation. METHODS: We retrospectively reviewed intubation devices used for all pediatric patients with microtia who had undergone reconstructive ear surgery at a single institution during the period January 2008 to December 2012. In each case, we identified the original airway management technique and success rate, as well as success rate for subsequent rescue techniques. The use of fiberoptic-assisted tracheal intubation was compared before and after introduction of a pediatric blade for the Pentax-AWS video laryngoscope. RESULTS: This study included 537 consecutive intubation procedures; 264 before and 273 after introduction of the pediatric airway scope. Elective use of fiberoptic-assisted tracheal intubation for anticipated difficult intubation was significantly less after introduction of the pediatric airway scope (before: 19 of 79, 24% vs after: 3 of 79, 4%; odds ratio 8.02; 95% confidence interval, 2.27 to 28.39; P = .0003), which achieved a 100% success rate when used as the primary technique in both routine and difficult airways. All 5 cases of failed direct laryngoscopy were rescued by the pediatric airway scope, thus eliminating emergency use of fiberscopy. CONCLUSION: Introduction of a pediatric video laryngoscope resulted in a substantial decrease in the use of fiberoptic-assisted tracheal intubation. This change in intubation method might not influence the success rate of intubation in experienced hands but could be relevant for novice users.

Application of gum elastic bougie to nasal intubation.

Gum elastic bougie (GEB), a useful device for difficult airway management, has seldom been used for nasotracheal intubation. Among 632 patients undergoing dental procedures or oral surgery, GEB was used successfully in 16 patients in whom conventional nasal intubation had failed because of anatomical problems or maldirection of the tip of the tracheal tube. We recommend that GEB should be applied from the first attempt for nasal intubation in patients with difficult airways.

[Postoperative analgesia after remifentanil].

Providing analgesia is the most important, yet the most difficult aspect of remifentanil anaesthesia, as its effect wears off quickly after infusion is terminated. Longer-acting opioids such as morphine and fentanyl must be given well before patients wake up. Bolus administration of fentanyl approximately 20 minutes before the end of surgery may provide adequate analgesia at emergence and tracheal extubation. However, fentanyl concentration decreases quite rapidly and patients may need repeated dosing until analgesia is attained. Continuous intraoperative low-dose infusion of fentanyl may lead to better analgesia than bolus dosing, because its context-sensitive half-time increases as the infusion lasts longer. Regional anaesthetic technique, such as epidural analgesia and peripheral nerve block can also be used in patients without coagulation abnormalities. Issue of acute tolerance after intraoperative use of remifentanil still awaits further study before final conclusion is reached. Some data suggest that we should not use an unnecessary and high dose of opioid without clear indication. Theoretically, remifentanil infusion can be used in ICU and surgical wards to manage postoperative pain in ventilated as well as spontaneously breathing patients. However, in some susceptible patients, even a very low-rate infusion can still cause significant respiratory depression more than 30 minutes after starting infusion. Pulse oximetry is not sensitive enough to detect early ventilatory depression when patients breathe oxygen-enriched air. Without continuous observation by trained anaesthetists, infusion of remifentanil should not be used casually particularly in non-ventilated patients.