Cervical Spine Motion During Tracheal Intubation Using an Optiscope Versus the McGrath Videolaryngoscope in Patients With Simulated Cervical Immobilization: A Prospective Randomized Crossover Study.

BACKGROUND: In patients with an unstable cervical spine, maintenance of cervical immobilization during tracheal intubation is important. In McGrath videolaryngoscopic intubation, lifting of the blade to raise the epiglottis is needed to visualize the glottis, but in patients with an unstable cervical spine, this can cause cervical spine movement. By contrast, the Optiscope, a rigid video-stylet, does not require raising of the epiglottis during tracheal intubation. We therefore hypothesized that the Optiscope would produce less cervical spine movement than the McGrath videolaryngoscope during tracheal intubation. The aim of this study was to compare the Optiscope with the McGrath videolaryngoscope with respect to cervical spine motion during intubation in patients with simulated cervical immobilization. METHODS: The primary outcome of the study was the extent of cervical spine motion at the occiput-C1, C1-C2, and C2-C5 segments. In this randomized crossover study, the cervical spine angle was measured before and during tracheal intubation using either the Optiscope or the McGrath videolaryngoscope in 21 patients with simulated cervical immobilization. Cervical spine motion was defined as the change in angle at each cervical segment during tracheal intubation. RESULTS: There was significantly less cervical spine motion at the occiput-C1 segment using the Optiscope rather than the McGrath videolaryngoscope (mean [98.33% CI]: 4.7° [2.4-7.0] vs 10.4° [8.1-12.7]; mean difference [98.33% CI]: -5.7° [-7.5 to -3.9]). There were also fewer cervical spinal motions at the C1-C2 and C2-C5 segments using the Optiscope (mean difference versus the McGrath videolaryngoscope [98.33% CI]: -2.4° [-3.7 to -1.2]) and -3.7° [-5.9 to -1.4], respectively). CONCLUSIONS: The Optiscope produces less cervical spine motion than the McGrath videolaryngoscope during tracheal intubation of patients with simulated cervical immobilization.

Intubation of non-difficult airways using video laryngoscope versus direct laryngoscope: a randomized, parallel-group study.

BACKGROUND: The video laryngoscope is recommended for intubating difficult airways. The present study aimed to determine whether the video laryngoscope can further improve intubation success rates compared with the direct laryngoscope in patients with non-difficult airways. METHODS: In total, 360 patients scheduled for elective abdominal surgeries were randomly assigned to undergo intubation using either a video laryngoscope (n = 179) or a direct laryngoscope (n = 181). The following parameters were measured: mouth opening; thyromental distance; sternomental distance; shape angle of the tracheal catheter; and glottic exposure grade. RESULTS: The percentage of patients with level I-II of total glottic exposure in the video laryngoscope group was 100% versus 63.5% in the direct laryngoscope group (P < 0.001). The one-attempt success rate of intubation was 96.1% using a video laryngoscope versus 90.1% using a direct laryngoscope (P = 0.024). The intubation success rate using a video laryngoscope was 100% versus 94.5% using a direct laryngoscope (P = 0.004). Immediate oropharyngeal injury occurred in 5.1% of patients intubated using a direct laryngoscope versus 1.1% using a video laryngoscope (P = 0.033). On postoperative day 1, obvious hoarseness was exhibited by 7.9% of patients intubated using a direct laryngoscope versus 2.8% using a video laryngoscope (P = 0.035). The grade of glottic exposure and catheter shape angle were independent risk factors for tracheal intubation failure. Thyromental distance, shape angle, glottic exposure time, and surgical position were independent risk factors for postoperative complications. Thyromental distance and glottic exposure time were independent risk factors for complications lasting > 2 days. CONCLUSIONS: Intubation using a video laryngoscope yielded significantly higher intubation success rates and significantly fewer postoperative complications than direct laryngoscopy in patients with non-difficult airways. TRIAL REGISTRATION: Chinese Clinical Trial Registry. No: ChiCTR-IOR-16009023 . Prospective registration.

Outcomes in video laryngoscopy studies from 2007 to 2017: systematic review and analysis of primary and secondary endpoints for a core set of outcomes in video laryngoscopy research.

BACKGROUND: Airway management is crucial and, probably, even the most important key competence in anaesthesiology, which directly influences patient safety and outcome. However, high-quality research is rarely published and studies usually have different primary or secondary endpoints which impedes clear unbiased comparisons between studies. The aim of the present study was to gather and analyse primary and secondary endpoints in video laryngoscopy studies being published over the last ten years and to create a core set of uniform or homogeneous outcomes (COS). METHODS: Retrospective analysis. Data were identified by using MEDLINE® database and the terms "video laryngoscopy" and "video laryngoscope" limited to the years 2007 to 2017. A total of 3351 studies were identified by the applied search strategy in PubMed. Papers were screened by two anaesthesiologists independently to identify study endpoints. The DELPHI method was used for consensus finding. RESULTS: In the 372 studies analysed and included, 49 different outcome categories/columns were reported. The items "time to intubation" (65.86%), "laryngeal view grade" (44.89%), "successful intubation rate" (36.56%), "number of intubation attempts" (23.39%), "complications" (21.24%), and "successful first-pass intubation rate" (19.09%) were reported most frequently. A total of 19 specific parameters is recommended. CONCLUSIONS: In recent video laryngoscopy studies, many different and inhomogeneous parameters were used as outcome descriptors/endpoints. Based on these findings, we recommend that 19 specific parameters (e.g., "time to intubation" (inserting the laryngoscope to first ventilation), "laryngeal view grade" (C&L and POGO), "successful intubation rate", etc.) should be used in coming research to facilitate future comparisons of video laryngoscopy studies.

Invasive EEG-electrodes in presurgical evaluation of epilepsies: Systematic analysis of implantation-, video-EEG-monitoring- and explantation-related complications, and review of literature.

INTRODUCTION: Stereoelectroencephalography (sEEG) is a diagnostic procedure for patients with refractory focal epilepsies that is performed to localize and define the epileptogenic zone. In contrast to grid electrodes, sEEG electrodes are implanted using minimal invasive operation techniques without large craniotomies. Previous studies provided good evidence that sEEG implantation is a safe and effective procedure; however, complications in asymptomatic patients after explantation may be underreported. The aim of this analysis was to systematically analyze clinical and imaging data following implantation and explantation. RESULTS: We analyzed 18 consecutive patients (mean age: 30.5 years, range: 12-46; 61% female) undergoing invasive presurgical video-EEG monitoring via sEEG electrodes (n = 167 implanted electrodes) over a period of 2.5 years with robot-assisted implantation. There were no neurological deficits reported after implantation or explantation in any of the enrolled patients. Postimplantation imaging showed a minimal subclinical subarachnoid hemorrhage in one patient and further workup revealed a previously unknown factor VII deficiency. No injuries or status epilepticus occurred during video-EEG monitoring. In one patient, a seizure-related asymptomatic cross break of two fixation screws was found and led to revision surgery. Unspecific symptoms like headaches or low-grade fever were present in 10 of 18 (56%) patients during the first days of video-EEG monitoring and were transient. Postexplantation imaging showed asymptomatic and small bleedings close to four electrodes (2.8%). CONCLUSION: Overall, sEEG is a safe and well-tolerated procedure. Systematic imaging after implantation and explantation helps to identify clinically silent complications of sEEG. In the literature, complication rates of up to 4.4% in sEEG and in 49.9% of subdural EEG are reported; however, systematic imaging after explantation was not performed throughout the studies, which may have led to underreporting of associated complications.

Measurement of forces applied using a Macintosh direct laryngoscope compared with a Glidescope video laryngoscope in patients with predictors of difficult laryngoscopy: A randomised controlled trial.

BACKGROUND: In patients with predictive features associated with easy direct laryngoscopy, videolaryngoscoy with the GlideScope has been shown to require less force when compared with Macintosh direct laryngoscopy. OBJECTIVE: The aim of this study was to compare forces applied with Glidescope vs. Macintosh laryngoscopes in patients with predictive features associated with difficult direct laryngoscopy. DESIGN: A randomised study. SETTING: Toronto General Hospital, a university tertiary centre in Canada. PATIENTS: Forty-four patients aged over 18 years, with one or more features of difficult intubation, undergoing elective surgery requiring single-lumen tracheal intubation. INTERVENTION: We measured the force applied to oropharyngeal tissues by attaching three FlexiForce Sensors (A201-25) to the concave surface of Macintosh and GlideScope laryngoscope blades.Anaesthetists or experienced anaesthesia residents performed laryngoscopies with both devices in a randomised sequence. MAIN OUTCOME MEASURES: The primary outcome was peak force. The secondary outcomes were average force and impulse force. The latter is the integral of the force over the time during which the force acted. RESULTS: Complete data were available for 40 individuals. Peak and average forces decreased with GlideScope (17 vs. 21 N, P = 0.03, and 6 vs. 11 N, P < 0.001, respectively). Laryngoscopy time increased with the GlideScope (30 vs. 18 s, P < 0.001), resulting in similar median impulse forces (206 vs. 175 N, P = 0.92). CONCLUSION: GlideScope laryngoscopy resulted in reduced peak and average forces, but as the laryngoscopy duration increased, the product of force and time (impulse force) was similar with both devices. TRIAL REGISTRATION: Clinicaltrials.gov Identifier: NCT01814176.

Hemodynamic responses to tracheal intubation with Bonfils compared to C-MAC videolaryngoscope: a randomized trial.

BACKGROUND: Direct laryngoscopy (DL) produce tachycardia and hypertension that could be fatal in a patient with a brain injury. Bonfils fiberscope and C-MAC videolaryngoscope are associated with little hemodynamic instability compared to DL. Scientific evidence comparing these two alternatives does not exist. We conducted this study to determine the hemodynamic effects of Bonfils compared to C-MAC in patients undergoing elective surgery. METHODS: Fifty (50) patients listed for elective surgery were randomly assigned to endotracheal intubation with Bonfils or C-MAC. After a standardized induction, intubation was done via the retromolar approach (Bonfils group) or via videolaryngoscopy (C-MAC group). A research assistant, who was not blinded to the intervention, recorded heart rate (HR) and arterial blood pressure (systolic, diastolic and mean arterial blood pressure [MAP]) at induction and at every minute during the 5 min post intubation. The primary outcome was the hemodynamic response to intubation, as verified every minute for the first 5 min compared to baseline value. RESULTS: After randomization, the two groups were comparable except for ASA I/II ratio which was slightly higher in the C-MAC group (p = 0.046). Heart rate (p = 0.40) and MAP (p = 0.30) were comparable between the two groups within 5 min post intubation. Intubation time was shorter with C-MAC than with Bonfils (30 ± 2 s vs 38 ± 2 s; p = 0.02). CONCLUSION: Hemodynamic responses to tracheal intubation using the Bonfils fiberscope is comparable to the C-MAC videolaryngoscope among patients scheduled for an elective surgery. In light of these findings, using either technique appears to be a reasonable course of action. TRIAL REGISTRATION: ISRCTN #34923 , retrospectively registered, 26/03/2018.

A Comparison of 3 Videolaryngoscopes for Double-Lumen Tube Intubation in Humans by Users With Mixed Experience: A Randomized Controlled Study.

OBJECTIVES: To test the hypothesis that laryngoscopy using the Airtraq (Prodol Limited, Viscaya, Spain) or King Vision laryngoscope (KVL) (Ambu A/S, Ballerup, Denmark) would result in a shorter time for successful double-lumen endobronchial tube (DLT) intubation by users with mixed experience than the time required using the Macintosh or GlideScope (Verathon Inc., Bothell, WA) laryngoscopes. DESIGN: A randomized, prospective, blind study. SETTING: A single university hospital. PARTICIPANTS: The study comprised 133 patients undergoing elective thoracic surgery. INTERVENTIONS: Patients were randomly allocated into the following 4 groups of DLTs: Macintosh (n = 32), GlideScope (n = 34), Airtraq (n = 35), or KVL (n = 32). MEASUREMENTS AND MAIN RESULTS: The following data were recorded: time required for achieving successful DLT intubation; glottis visualization; optimization maneuvers; first-pass success rate; intubation difficulty; failure to intubate, defined as an attempt taking >150 seconds to perform or if peripheral oxygen saturation <92% was noted; and postoperative sore throat and hoarseness were recorded. Compared with GlideScope, the Airtraq resulted in shorter times for achieving successful DLT intubation (median times: 21 s [95% confidence interval 23.9-70.8 s] v 57.5 s [95% confidence interval 46.2-89.1 s], respectively; p = 0.021); a lower score for difficult intubations (p = 0.023); and fewer optimization maneuvers. The 4 laryngoscopes were associated with comparable glottis visualization; first-pass success rate (100%, 100%, 94.4%, and 100%, respectively; p = 0.522); incidence of oropharyngeal trauma; postoperative sore throat; and hoarseness of voice. There were 2 (5.7%) endobronchial intubation failures using the Airtraq due to the inability to advance the DLT through the glottis opening. The experience of the anesthesiologists in using the 4 devices had a statistically significant negative correlation with the time to confirmation of endobronchial intubation (Spearman r -0.392; p < 0.001). CONCLUSION: When used by operators with mixed experience, the channeled Airtraq required less time for DLT intubation and was easier to use than the GlideScope, although failures did occur with the Airtraq, whereas they did not occur with the other systems.

A Randomized Controlled Trial Comparing the Utility of Lighted Stylet and GlideScope for Double-Lumen Endobronchial Intubation.

OBJECTIVE: To compare GlideScope and lighted stylet for double-lumen endobronchial tube (DLT) intubation in terms of intubation time, success rate of first attempt at intubation, difficulty in DLT advancement toward the glottis, and postoperative sore throat and hoarseness. DESIGN: A prospective, randomized study. SETTING: Medical center governed by a university hostpial. PARTICIPANTS: Sixty-two adult patients undergoing thoracic surgery using DLT intubation. INTERVENTION: After the induction of anesthesia, DLT intubation was performed using GlideScope (n = 32) or lighted stylet (n = 32). MEASUREMENTS AND MAIN RESULTS: Number of intubation attempts, difficulty of DLT advancement toward the glottis, time taken for DLT intubation, and the incidence and severity of postoperative sore throat and hoarseness at 1 and 24 hours after surgery were evaluated. Time taken for DLT intubation was shorter in the lighted stylet group compared with the GlideScope group (30 [28-32] s v 45 [38-53] s, median [interquartile range], respectively; p < 0.001). DLT advancement toward the glottis was easier in the lighted stylet group than in the GlideScope group (p = 0.016). The success rate of DLT intubation in the first attempt (96.9% v 90.6% for lighted stylet and GlideScope, respectively), and the incidence and severity of postoperative sore throat and hoarseness were not different between the two groups. CONCLUSIONS: The use of lighted stylet allowed easier advancement of the DLT toward the glottis in the oropharyngeal space and reduced time for achieving DLT intubation compared with GlideScope.

Bronchoscopy versus an endotracheal tube mounted camera for the peri-interventional visualization of percutaneous dilatational tracheostomy - a prospective, randomized trial (VivaPDT).

BACKGROUND: Percutaneous dilatational tracheostomy (PDT) in critically ill patients often involves bronchoscopic optical guidance. However, this procedure is not without disadvantages. Therefore, we aimed to study a recently introduced endotracheal tube-mounted camera (VivaSightTM-SL tube [VST]; ETView, Misgav, Israel) for guiding PDT. METHODS: This was a randomized controlled trial involving 46 critically ill patients who received PDT using optical guidance with a VST or with bronchoscopy. The primary outcome measure was visualization of the tracheal structures (i.e., identification and monitoring of the thyroid, cricoid, and tracheal cartilage and the posterior wall) rated on 4-point Likert scales. Secondary measures were the quality of ventilation (before puncture and during the tracheostomy procedure rated on 4-point Likert scales) and blood gases sampled at standardized time points. RESULTS: The mean ratings for visualization (lower values better; values given for per-protocol analysis) were 5.4 (95% CI 4.5-6.3) for the VST group and 4.0 (95% CI 4.0-4.0) for the bronchoscopy group (p < 0.001). Mean ventilation ratings were 2.5 (95% CI 2.1-2.9) for VST and 5.0 (95% CI 4.4-5.7) for bronchoscopy (p < 0.001). Arterial carbon dioxide increased to 5.9 (95% CI 5.4-6.5) kPa in the VST group vs. 8.3 (95% CI 7.2-9.5) kPa in the bronchoscopy group (p < 0.001), and pH decreased to 7.40 (95% CI 7.36-7.43) in the VST group vs. 7.26 (95% CI 7.22-7.30) in the bronchoscopy group (p < 0.001), at the end of the intervention. CONCLUSIONS: Visualization of PDT with the VST is not noninferior to guidance by bronchoscopy. Ventilation is superior with less hypercarbia with the VST. Because visualization is not a prerequisite for PDT, patients requiring stable ventilation with normocarbia may benefit from PDT with the VST. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02861001 . Registered on 13 June 2016.

Bougies as an aid for endotracheal intubation with the Airway Scope: bench and manikin comparison studies.

BACKGROUND: When encountering a difficult airway with an Airway Scope (AWS) a bougie can be inserted into the endotracheal tube in the AWS channel. The angulated tip of the bougie can be guided toward the glottis by rotating it. We tested the ease of rotating bougies (Venn reusable, Boussignac, Portex single-use, and Frova) in an endotracheal tube when placed in the AWS channel. METHODS: Bench study: Seven anesthesiologists inserted each of the four types of bougies into a 7.0 mm endotracheal tube in an AWS channel and rotated the bougie end (side of bougie operated by hand) clockwise or counterclockwise to an angle of 0°-180° in 45° increments. The rotation angle of the bougie tip (tracheal side) was measured for each bougie and the degree of force required to rotate them was examined. Manikin study: Using the same four bougies, the same seven anesthesiologists attempted to intubate a manikin that simulated a difficult airway. Success rate and time required for successful intubation were compared between the four bougies. RESULTS: Bench study: The difference in the rotation angle between the bougie tip and end was significantly larger with Portex single-use and Frova bougies than with Venn reusable and Boussignac bougies (P < 0.01). The rotation angles of the tips of Venn reusable, Boussignac, Portex single-use, and Frova bougies were 145°/123° (clockwise / counterclockwise), 92°/108°, 46°/56°, and 39°/51°, respectively, when their ends were rotated to an angle of 180°. Venn reusable and Boussignac bougies could be rotated in the endotracheal tube by clinically acceptable rotational force. Manikin study: Times to intubation with Venn reusable [25 (SD, 5) s] and Boussignac bougies [35 (6) s] were significantly shorter than with Portex single-use [61 (17) s] and Frova bougies [69 (22) s] (P < 0.01). There were no significant differences in success rate between the four bougies. CONCLUSIONS: Venn reusable and Boussignac bougies are a useful aid for intubation with an AWS. Portex single-use and Frova bougies seem to be less suitable for this technique. Different bougies may be of varying utility when used with an AWS or airway device with an endotracheal tube channel.

Less is more: time to expand the indications for minimally invasive video-assisted parathyroidectomy.

PURPOSE: Minimally invasive video-assisted parathyroidectomy (MIVAP) is one of the most widespread targeted parathyroid surgeries for primary hyperparathyroidism (PHP). The aim of this study was to assess its limits and propose an expansion of its indications in the management of parathyroid pathology. METHODS: A retrospective analysis of 77 consecutive patients who underwent MIVAP for PHP between Jan and Oct 2016 was conducted. The adequacy of the procedure and/or the need to convert to a standard cervicotomy was the main outcome of interest. Secondary outcomes of interest included: operative time, postoperative morbidity, postoperative pain assessed by the visual analogue scale (VAS) score, and the length of the surgical incision. RESULTS: There were 64 females and 13 males with a mean age of 51 years. In one patient a concomitant en bloc thyroid lobectomy was required due to features suspicious of parathyroid carcinoma while exploration was required in two other patients. None of these three cases required conversion to standard cervicotomy. The mean operative time, length of incision and VAS score was 31 min, 17 mm and 1.6, respectively. Biochemical cure was achieved in all patients, and no postoperative morbidities were reported. CONCLUSION: MIVAP offers the ability to perform a neck exploration and/or an en bloc thyroid lobectomy without the need to convert to a standard cervicotomy. Therefore, it not only serves as a targeted parathyroid procedure but also a potential alternative to full neck exploration.

[Primary Hyperthyroidism. Minimally invasive video-assisted parathyroidectomy] / Hiperparatiroidismo primario. Paratiroidectomia miniinvasiva videoasistida

Objective: Show our experience performing the minimally invasive video-assisted parathyroidectomy with central approach for the treatment of patients with primary hyperparathyroidism without using intraoperative parathyroid hormone monitoring (IPTHM) based solely on the concordance of two preoperative localization studies. Material and methods: An informed consent for the accomplishment of a minimally invasive approach was performed on 27 selected patients diagnosed with primary hyperparathyroidism who underwent pre-operative cervical ultrasound and sesta-MIBI scintigraphy studies, which were consistent across them. None had a family history that might indicate a multiple endocrine neoplasia (MEN), known thyroid disease, previous neck incision, or suspicion of carcinoma. Surgery was performed through a 1.5 cm central cervical incision and the use of harmonic scalpel. IPTHM was not performed in either case. Results: In all cases the topographic location of the adenoma was confirmed. No signs of hyperparathyroidism persistence or recurrence were registered after a follow-up period of 42 months. There were no recurrent nerve lesions. The average operative time was 24.5 minutes and all patients were discharged within 24 hours. The analgesic requirement was minimal and the cosmetic result satisfactory. Conclusion: The minimally invasive unilateral exploration of the parathyroids with video-assisted magnification without IPTHM, under the guidance of two concordant localization studies is safe and feasible, with comparable results to those of standard technique as well as aesthetic advantages, less postoperative pain and reduced hospitalization.

Objetivo: Mostrar nuestra experiencia realizando la paratiroidectomía miniinvasiva video-asistida con abordaje central para el tratamiento de pacientes con hiperparatiroidismo primario, sin utilizar el monitoreo intraoperatorio de paratohormona (mipth), basados únicamente en la concordancia de dos estudios de localización preoperatorios. Material y métodos: Se seleccionaron 27 pacientes con diagnóstico de hiperparatiroidismo primario, a los cuales se les realizó previo su consentimiento para la realización de un abordaje miniinvasivo, una ecografía cervical y una centellografía sesta-MIBI como estudios de localización pre-operatorios, los cuales fueron concordantes en todo ellos. Ninguno presentó antecedentes familiares que hicieran sospechar una neoplasia endócrina múltiple (NEM), enfermedad tiroidea conocida, cervicotomía previa, ni sospecha de carcinoma. La cirugía se realizó a través de una incisión cervical central de 1,5 cm. con el empleo del bisturí harmónico. El mipth no se realizó en ninguno de los casos. Resultados: En todos los casos se confirmó la ubicación topográfica del adenoma. No registramos persistencias del hiperparatiroidismo ni recidivas después de un período de seguimiento de 42 meses. No hubo lesiones recurrenciales. El tiempo quirúrgico promedio fue de 24,5 minutos y todos los pacientes se fueron de alta antes de las 24 horas. El requerimiento analgésico fue mínimo, y el resultado estético satisfactorio. Conclusión: La exploración unilateral miniinvasiva de las paratiroides con magnificación videoasistida sin mipth, bajo la guía de dos estudios de localización concordantes, es un procedimiento seguro y factible, con resultados comparables a los de la técnica estándar y con ventajas en lo estético, menor dolor postoperatorio y hospitalización reducida.

Comparison of Macintosh, McCoy and C-MAC D-Blade video laryngoscope intubation by prehospital emergency health workers: a simulation study.

The aim of the this study is to evaluate the intubation success rates of emergency medical technicians using a Macintosh laryngoscope (ML), McCoy laryngoscope (MCL), and C MAC D-Blade (CMDB) video laryngoscope on manikin models with immobilized cervical spines. This randomized crossover study included 40 EMTs with at least 2 years' active service in ambulances. All participating technicians completed intubations in three scenarios-a normal airway model, a rigid cervical collar model, and a manual in-line cervical stabilization model-with three different laryngoscopes. The scenario and laryngoscope model were determined randomly. We recorded the scenario, laryngoscope method, intubation time in seconds, tooth pressure, and intubation on a previously prepared study form. We performed Friedman tests to determine whether there is a significant change in the intubation success rate, duration of tracheal intubation, tooth pressure, and visual analog scale scores due to violations of parametric test assumptions. We performed the Wilcoxon test to determine the significance of pairwise differences for multiple comparisons. An overall 5 % type I error level was used to infer statistical significance. We considered a p value of less than 0.05 statistically significant. The CMDB and MCL success rates were significantly higher than the ML rates in all scenario models (p < 0.05). The CMDB intubation duration was significantly shorter when compared with ML and MCL in all models. CMDB and MCL may provide an easier, faster intubation by prehospital emergency health care workers in patients with immobilized cervical spines.

C-MAC videolaryngoscope compared with direct laryngoscopy for rapid sequence intubation in an emergency department: A randomised clinical trial.

BACKGROUND: Airway management in the emergency room can be challenging when patients suffer from life-threatening conditions. Mental stress, ignorance of the patient's medical history, potential cervical injury or immobilisation and the presence of vomit and/or blood may also contribute to a difficult airway. Videolaryngoscopes have been introduced into clinical practice to visualise the airway and ultimately increase the success rate of airway management. OBJECTIVE: The aim of this study was to test the hypothesis that the C-MAC videolaryngoscope improves first-attempt intubation success rate compared with direct laryngoscopy in patients undergoing emergency rapid sequence intubation in the emergency room setting. DESIGN: A randomised clinical trial. SETTING: Emergency Department of the University Hospital, Zurich, Switzerland. PATIENTS: With approval of the local ethics committee, we prospectively enrolled 150 patients between 18 and 99 years of age requiring emergency rapid sequence intubation in the emergency room of the University Hospital Zurich. Patients were randomised (1 : 1) to undergo tracheal intubation using the C-MAC videolaryngoscope or by direct laryngoscopy. INTERVENTIONS: Owing to ethical considerations, patients who had sustained maxillo-facial trauma, immobilised cervical spine, known difficult airway or ongoing cardiopulmonary resuscitation were excluded from our study. All intubations were performed by one of three very experienced anaesthesia consultants. MAIN OUTCOME MEASURES: First-attempt success rate served as our primary outcome parameter. Secondary outcome parameters were time to intubation; total number of intubation attempts; Cormack and Lehane score; inadvertent oesophageal intubation; ease of intubation; complications including violations of the teeth, injury/bleeding of the larynx/pharynx and aspiration/regurgitation of gastric contents; necessity of using further alternative airway devices for successful intubation; maximum decrease of oxygen saturation and technical problems with the device. RESULTS: A total of 150 patients were enrolled, but three patients had to be excluded from the analysis, resulting in 74 patients in the C-MAC videolaryngoscopy group and 73 patients in the direct laryngoscopy group. Tracheal intubation was achieved successfully at the first attempt in 73 of 74 patients in the C-MAC group and all patients in the direct laryngoscopy group (P = 1.0). Time to intubation was similar (32 ±â€Š11 vs. 31 ±â€Š9 s, P = 0.51) in both groups. Visualisation of the vocal cords, represented as the Cormack and Lehane score, was significantly better using the C-MAC videolaryngoscope (P < 0.001). CONCLUSION: Our study demonstrates that visualisation of the vocal cords was improved by using the C-MAC videolaryngoscope compared with direct laryngoscopy. Better visualisation did not improve first-attempt success rate, which in turn was probably based on the high level of experience of the participating anaesthesia consultants. TRIAL REGISTRATION: Clinicaltrials.gov identifier NCT02297113.

Hands-Off Time for Endotracheal Intubation during CPR Is Not Altered by the Use of the C-MAC Video-Laryngoscope Compared to Conventional Direct Laryngoscopy. A Randomized Crossover Manikin Study.

INTRODUCTION: Sufficient ventilation and oxygenation through proper airway management is essential in patients undergoing cardio-pulmonary resuscitation (CPR). Although widely discussed, securing the airway using an endotracheal tube is considered the standard of care. Endotracheal intubation may be challenging and causes prolonged interruption of chest compressions. Videolaryngoscopes have been introduced to better visualize the vocal cords and accelerate intubation, which makes endotracheal intubation much safer and may contribute to intubation success. Therefore, we aimed to compare hands-off time and intubation success of direct laryngoscopy with videolaryngoscopy (C-MAC, Karl Storz, Tuttlingen, Germany) in a randomized, cross-over manikin study. METHODS: Twenty-six anesthesia residents and twelve anesthesia consultants of the University Hospital Zurich were recruited through a voluntary enrolment. All participants performed endotracheal intubation using direct laryngoscopy and C-MAC in a random order during ongoing chest compressions. Participants were strictly advised to stop chest compression only if necessary. RESULTS: The median hands-off time was 1.9 seconds in direct laryngoscopy, compared to 3 seconds in the C-MAC group. In direct laryngoscopy 39 intubation attempts were recorded, resulting in an overall first intubation attempt success rate of 97%, compared to 38 intubation attempts and 100% overall first intubation attempt success rate in the C-MAC group. CONCLUSION: As a conclusion, the results of our manikin-study demonstrate that video laryngoscopes might not be beneficial compared to conventional, direct laryngoscopy in easily accessible airways under CPR conditions and in experienced hands. The benefits of video laryngoscopes are of course more distinct in overcoming difficult airways, as it converts a potential "blind intubation" into an intubation under visual control.

Use-Dependent Curvature Changes in the GlideRite® Reusable Intubation Stylet.

The Glidescope® is one of the most widely used video laryngoscopes in the market. It is often used with a purpose-built, reusable, "nonmalleable" stainless steel stylet, the GlideRite®. In this study, we investigated whether this stylet retains its original curvature with repeated use and sterilization. To evaluate the shape and curvature of the stylets, high-resolution digital photographs were made of 55 GlideRite stylets (5 new and 50 randomly selected from operating room stock) laid on a grid background and analyzed using Adobe Photoshop®. In a similar fashion, 1 new stylet was inserted into and removed 100 times from an endotracheal tube and photographed every 20 cycles to determine the impact of use on stylet shape. For the 5 new stylets, the handle-to-tip angle was very consistent (23.44° ± 1.04°). The stylets in clinical use varied widely in their configuration. For analysis, they were divided into 3 groups based on the handle-to-tip angle: ±1 SD of the new stylets, those with a shallower angle (straighter), and those with a steeper angle (more curved). The handle-to-tip angles were as follows: 23.07° ± 0.80° (±1 SD), 18.39° ± 2.59° (straighter), and 27.65° ± 2.73° (more curved). Analysis of variance showed that the new and ±1 SD groups were not significantly different, but both the straighter (P = 0.0002) and more curved (P = 0.0048) groups were significantly different from new. The repeated insertion and removal of a new stylet resulted in gradual straightening of the curve of the stylet from 22° at baseline to 19.2° after 100 insertion/removal cycles. Used GlideRite reusable stylets are not reliably equivalent to new ones in terms of their shape or curvature. Given that the repeated insertion and removal of a new stylet from an endotracheal tube resulted in their straightening, it is likely that clinical use has the same effect. Because many used stylets were actually more curved than the new ones, we hypothesize that practitioners likely bend the nonmalleable stylets to improve clinical utility, but often fail to recapture the manufacturer-intended curve. The clinical relevance of the change in shape of the GlideRite stylet remains to be determined; it is that possible intubation may be more difficult than expected compared with the use of new stylets.

Comparison of GlideScope video laryngoscopy and Macintosh laryngoscope in ear-nose and throat surgery.

AIM: Endotracheal intubation procedure employed during general anaesthesia is the most effective way for keeping the airways and respiration under control and has low risk of complications. We have aimed in this study to compare the first-attempt success and duration of the endotracheal intubation process and its effects on haemodynamics using the Macintosh laryngoscope and the GlideScope video laryngoscope. METHODS: In this prospective randomized single-centre study, 100 patients of 18-65 years of age, and classified within the American Society of Anaesthesiologists' (ASA) I-II risk groups before elective ear-nose and throat surgery were included. The patients were randomly divided into two groups, designated as Group M, to be intubated using the Macintosh laryngoscope, and as Group G, to be intubated using the GlideScope video laryngoscope. The Mallampati scores, Cormack-Lehane classifications, intubation duration, number of attempts at intubation, the haemodynamic response and the complications were recorded. RESULTS: There were not intergroup differences with respect to the number of intubation attempts, the Mallampati and Cormack-Lehane classifications. Duration of intubation was found to be longer in group G. The haemodynamic response values of group M were higher than those of group G. Although there was no statistically significant difference between the two groups in the number of intubation attempts, two of the patients in group M were intubated in the second attempt. CONCLUSION: In our study, despite the longer intubation times in group G, the haemodynamic response was significantly lower in this group. It is believed that especially in cases with vital requirement of haemodynamic stability, the GlideScope video laryngoscope would be safer to employ.