Ambu AuraGain versus intubating laryngeal tube suction as a conduit for endotracheal intubation.

BACKGROUND AND AIMS: Newly developed supraglottic airway devices (SGAs) are designed to be used both for ventilation and as conduits for endotracheal intubation with standard endotracheal tubes (ETTs). We compared the efficacy of the Ambu AuraGain (AAG) and the newly developed intubating laryngeal tube suction disposable (ILTS-D) as conduits for blind and fiber-optically guided endotracheal intubation in an airway mannequin. MATERIAL AND METHODS: This is a prospective, randomized, crossover study in an airway mannequin, with two arms: blind ETT insertion by medical students and fiber-optically guided ETT insertion by anesthesiologists. The primary outcome variable was the time to achieve an effective airway through an ETT using AAG and ILTS-D as conduits. Secondary outcome variables were the time to achieve effective supraglottic ventilation and successful exchange with an ETT, and the success rates for blind endotracheal intubation and fiber-optically guided intubation techniques for both SGAs. RESULTS: Forty participants were recruited to each group. All participants were able to insert both devices successfully on the first attempt. For blind intubation, the success rate for establishing a definitive airway with an ETT using the SGA as a conduit was significantly higher with ILTS-D (82.5%) compared with AAG (20.0%) (P < 0.001). None of the participants were able to successfully complete the exchange of the SGA for the ETT with the AAG. In the fiber optic guided intubation group, the rate of successful exchange was significantly higher with ILTS-D (84.6%) compared with AAG (61.5%) (P = 0.041). CONCLUSION: The ILTS-D successfully performs in an airway mannequin with higher success rate and shorter time for blindly establishing an airway with an ETT using the SGA as a conduit, compared with AAG. Further clinical trials are warranted.

Comparison of 2 techniques of laryngeal tube exchange in a randomized controlled simulation study.

BACKGROUND: Laryngeal tubes (LT) are often used as rescue airway devices. Among prehospital medical personnel, the success rates are high and significantly faster compared to an endotracheal tube (ETT). Therefore, LTs are increasingly used in the prehospital setting. The exchange of an LT for an ETT may often be desirable. Two fiberoptic bronchoscope-facilitated techniques have been described to exchange an LT for an ETT: an intraluminal technique using an Aintree intubating catheter and an extraluminal technique using a nasal route alongside the LT. In this randomized cross-over mannequin study, we compared the intraluminal with the extraluminal exchange technique. The primary outcome was time to achieve an effective airway through an ETT. We hypothesized that the intraluminal technique would be significantly faster. METHODS: Thirty anesthesia providers were recruited to the study. Each participant attempted both techniques in an intubation simulation model. The tube exchange time was recorded from picking up the fiberoptic bronchoscope until confirmation of ventilation with the ETT. RESULTS: Four participants in each group had a failed attempt at intubation. Time to establish an endotracheal intubation was significantly shorter with the intraluminal technique vs the extraluminal technique (77.5 vs 140 seconds; P=.03). CONCLUSION: Based on the results of our study, we suggest that the intraluminal technique may be a suitable alternative for a fiberoptic-guided rapid exchange of an LT for an ETT to establish an effective airway in a challenging situation.

Emergent airway management in a case of fibrodysplasia ossificans progressiva.

Fibrodysplasia ossificans progressiva (FOP), or Stone man syndrome, is rare and one of the most disabling genetic conditions of the connective tissue due to progressive extraskeletal ossification. It usually presents in the first decade of life as painful inflammatory swellings, either spontaneously or in response to trauma, which later ossify and lead to severe disability. Progressive spinal deformity including thoracolumbar kyphoscoliosis leads to thoracic insufficiency syndrome, increasing the risk for pneumonia and right sided heart failure. We present the airway management in a 22-year-old male, diagnosed with FOP with severe disability, who required urgent airway intervention as a result of respiratory failure from pnuemonia. Tracheostomy triggers ossification and consequent airway obstruction at the tracheostomy site and laryngoscopy triggers temporomandibular joint ankylosis. Therefore, awake fiber-optic endotracheal intubation is recommended in these patients. Use of an airway endoscopy mask enabled us to simultaneously maintain non-invasive ventilation and intubate the patient in a situation where tracheostomy needed to be avoided.

The prediction of difficult intubation in obese patients using mirror indirect laryngoscopy: A prospective pilot study.

BACKGROUND: The incidence of difficult laryngoscopy and intubation in obese patients is higher than in the general population. Classical predictors of difficult laryngoscopy and intubation have been shown to be unreliable. We prospectively evaluated indirect mirror laryngoscopy as a predictor of difficult laryngoscopy in obese patients. MATERIALS AND METHODS: 60 patients with a body mass index (BMI) greater than 30, scheduled to undergo general anesthesia, were enrolled. Indirect mirror laryngoscopy was performed and was graded 1-4 according to Cormack and Lehane. A view of grade 3-4 was classified as predicting difficult laryngoscopy. Additional assessments for comparison were the Samsoon and Young modification of the Mallampati airway classification, Wilson Risk Sum Score, neck circumference, and BMI. The view obtained upon direct laryngoscopy after induction of general anesthesia was classified according to Cormack and Lehane as grade 1-4. RESULTS: Sixty patients met the inclusion criteria; however, 8 (13.3%) patients had an excessive gag reflex, and examination of the larynx was not possible. 15.4% of patients who underwent direct laryngoscopy had a Cormack and Lehane grade 3 or 4 view and were classified as difficult. Mirror laryngoscopy had a tendency toward statistical significance in predicting difficult laryngoscopy in these patients. CONCLUSIONS: This study is consistent with previous studies, which have demonstrated that no one individual traditional test has proven to be adequate in predicting difficult airways in the obese population. However, the new application of an old test - indirect mirror laryngoscopy - could be a useful additional test to predict difficult laryngoscopy in obese patients.

Rhythmic movement disorder after general anesthesia.

Dystonic movements after general anesthesia are very rare. The differential diagnosis includes adverse drug reaction, local anesthetic reaction, emergence delirium, hysterical response, and shivering. We present a case of a 10-year-old, otherwise healthy girl undergoing outpatient foot surgery. Involuntary jerking movements of her arms and torso every time she would drift off to sleep started about 2.5 hours after emergence from general anesthesia. The patient was easily arousable and absolutely unaware of the movements. These movements lasted for several days before they resolved completely. We believe to present the first case of sleep-related rhythmic movement disorder after general anesthesia, considering the nature of the movements in our patient.

A proposed classification of simulators.

This paper provides a coherent and comprehensive classification of simulators, using a five letter coding system, and is based on the characteristics of the user interface and the logic controller.