Comparison of Force Distribution during Laryngoscopy with the C-MAC D-BLADE and Macintosh-Style Blades: A Randomised Controlled Clinical Trial.

Background: The geometry of a laryngoscope's blade determines the forces acting on the pharyngeal structures to a relevant degree. Knowledge about the force distribution along the blade may prospectively allow for the development of less traumatic blades. Therefore, we examined the forces along the blades experienced during laryngoscopy with the C-MAC D-BLADE and blades of the Macintosh style. We hypothesised that lower peak forces are applied to the patient's pharyngeal tissue during videolaryngoscopy with a C-MAC D-BLADE compared to videolaryngoscopy with a C-MAC Macintosh-style blade and direct laryngoscopy with a Macintosh-style blade. Beyond that, we assumed that the distribution of forces along the blade differs depending on the respective blade's geometry. Methods: After ethical approval, videolaryngoscopy with the D-BLADE or the Macintosh blade, or direct laryngoscopy with the Macintosh blade (all KARL STORZ, Tuttlingen, Germany), was performed on 164 randomly assigned patients. Forces were measured at six positions along each blade and compared with regard to mean force, peak force and spatial distribution. Furthermore, the duration of the laryngoscopy was measured. Results: Mean forces (all p < 0.011) and peak forces at each sensor position (all p < 0.019) were the lowest with the D-BLADE, whereas there were no differences between videolaryngoscopy and direct laryngoscopy with the Macintosh blades (all p > 0.128). With the D-BLADE, the forces were highest at the blade's tip. In contrast, the forces were more evenly distributed along the Macintosh blades. Videolaryngoscopy took the longest with the D-BLADE (p = 0.007). Conclusions: Laryngoscopy with the D-BLADE resulted in significantly lower forces acting on pharyngeal and laryngeal tissue compared to Macintosh-style blades. Interestingly, with the Macintosh blades, we found no advantage for videolaryngoscopy in terms of force application.

A comparative evaluation of fibreoptic bronchoscopy versus C-MAC® D-BLADE-guided videolaryngoscopy for nasotracheal intubation under general anesthesia in oropharyngeal carcinoma surgery patients.

PURPOSE: Nasotracheal intubation (NTI) is required for surgery in oropharyngeal (OP) carcinoma patients, but it may be challenging because of distorted anatomy, mucosal congestion, and increased risk of bleeding. Flexible bronchoscopy (FB)-guided NTI is preferred in these cases but has limitations. In this randomized controlled study, we sought to compare C-MAC® D-BLADE-guided videolaryngoscopy (VL) (Karl Storz SE & Co. KG, Tuttlingen, Germany) with FB for NTI under general anesthesia in patients with OP carcinomas. METHODS: We randomized a total of 100 patients with OP carcinoma and El-Ganzouri's risk index (EGRI) < 7 to undergo NTI under general anesthesia with FB (n = 50) or C-MAC D-BLADE-guided VL (n = 50). The primary outcome was the total intubation time. We also recorded the time to glottis view, nasal intubation difficulty scale (NIDS) score, best percentage of glottis opening score, and complications. RESULTS: The median [interquartile range (IQR)] total intubation time was shorter with VL than with FB (total intubation time, 38 [26-43] sec vs 60 [52-65] sec; difference, -20 sec [95% confidence interval (CI), -27 to -11]; P < 0.001). Similarly, the median [IQR] time to glottis view was shorter with VL compared to FB (8 [6-9] sec vs 22 [14-25] sec; difference, -13 sec [95% CI, -17 to -10]; P < 0.001). The median NIDS score was higher with VL (difference, 2 [95% CI, 2 to 3]; P < 0.001). The incidences of airway trauma (two cases with FB vs seven with VL; P = 0.30) and postoperative sore throat (ten cases in both groups; P = 0.56) were similar. CONCLUSION: Compared to FB, C-MAC D-BLADE-based VL reduced the total time for nasal intubation oropharyngeal carcinoma patients, potentially representing an acceptable alternative in selected cases. TRIAL REGISTRATION: CTRI.nic.in (2018/11/0162830); first submitted 8 November 2018.

RéSUMé: OBJECTIF: L'intubation nasotrachéale est nécessaire pour la chirurgie chez la patientèle atteinte de carcinome oropharyngé, mais elle peut être difficile en raison d'une anatomie déformée, d'une congestion des muqueuses et d'un risque accru de saignement. Dans ces cas, il est préférable d'utiliser une intubation nasotrachéale guidée par bronchoscopie flexible (BF), mais cette modalité a ses limites. Dans cette étude randomisée contrôlée, nous avons cherché à comparer la vidéolaryngoscopie guidée par lame D-BLADE C-MAC® (VL) (Karl Storz SE & Co. KG, Tuttlingen, Allemagne) à la BF pour réaliser l'intubation nasotrachéale sous anesthésie générale chez les patient·es ayant un carcinome oropharyngé. MéTHODE: Au total, nous avons randomisé 100 personnes atteintes d'un carcinome oropharyngé et présentant un indice de risque d'El-Ganzouri (EGRI) < 7 à bénéficier d'une intubation nasotrachéale sous anesthésie générale par BF (n = 50) ou par VL guidée par lame D-BLADE C-MAC (n = 50). Le critère d'évaluation principal était le temps d'intubation total. Nous avons également enregistré le temps écoulé jusqu'à la visualisation de la glotte, le score sur l'échelle de difficulté de l'intubation nasale (NIDS), le meilleur pourcentage de score d'ouverture de la glotte et les complications. RéSULTATS: La durée totale d'intubation médiane [écart interquartile (ÉIQ)] était plus courte avec la VL qu'avec la BF (durée totale d'intubation, 38 [26­43] sec vs 60 [52 à 65] secondes; différence, −20 sec [intervalle de confiance (IC) à 95 %, −27 à −11]; P < 0,001). De même, le temps médian [ÉIQ] jusqu'à la visualisation de la glotte était plus court avec la VL qu'avec la BF (8 [6­9] sec vs 22 [14 à 25] secondes; différence, −13 sec [IC 95 %, −17 à −10]; P < 0,001). Le score médian sur l'échelle NIDS était plus élevé avec la VL (différence, 2 [IC 95 %, 2 à 3]; P < 0,001). L'incidence des traumatismes des voies aériennes (deux cas avec la BF vs sept avec la VL; P = 0,30) et le mal de gorge postopératoire (dix cas dans les deux groupes; P = 0,56) étaient similaires. CONCLUSION: Par rapport à la BF, la VL guidée par lame D-BLADE C-MAC a réduit le temps total d'intubation nasale pour les personnes atteintes d'un carcinome oropharyngé, ce qui représente potentiellement une alternative acceptable dans certains cas. ENREGISTREMENT DE L'éTUDE: CTRI.nic.in (2018/11/0162830); première soumission le 8 novembre 2018.

A comparative study of the C-MAC D-blade videolaryngoscope and McCoy laryngoscope for oro-tracheal intubation with manual in-line stabilization of neck in patients undergoing cervical spine surgery.

Background and Aims: Airway management in cervical spine injury patients requires manual in-line stabilization (MILS) of the neck to avoid exacerbation of cord injury, which impedes visualization of glottis during laryngoscopy. Specially designed blades such as McCoy and C-MAC D-blades can improve laryngoscopic view in such patients. This study was performed to compare the efficacy of C-MAC D-blades and the McCoy laryngoscope for oro-tracheal intubation using MILS in patients undergoing cervical spine surgery. Material and Methods: This randomized, prospective study was performed in 60 adult patients of American Society of Anesthesiologists grade I-III, either sex, 18 to 60 years of age undergoing elective cervical spine surgery. Patients were randomly categorized into two groups, group D and group M. Intubation was performed using a C-MAC D-blade videolaryngoscope in group D and a McCoy laryngoscope in group M using MILS. The intubation difficulty scale (IDS) score, laryngoscopy and intubation times, percentage of glottic opening (POGO) score, Cormack Lehane (CL) grading with and without external laryngeal pressure (ELP), need for bougie or change of blade or operator, and change in hemodynamics following intubation were recorded. Results: Group D showed lower mean IDS scores than group M (P value < 0.0001). There were statistically significant differences found in duration of laryngoscopy (group D < group M), CL grading without ELP (group D: CL-1,2a >CL-2b, 3; group M: CL-1,2a group M), need for ELP and lifting force (group D < group M), and hemodynamic responses after intubation (group D < group M). Conclusion: A C-MAC D-blade videolaryngoscope provides better and rapid visualization of glottis with less intubation difficulties than a McCoy laryngoscope during intubation using MILS in patients with cervical spine injury.

GlideScope versus C-MAC D-blade videolaryngoscope for double-lumen tube intubation in patients with anticipated difficult airways: A multi-center, prospective, randomized, controlled trial.

STUDY OBJECTIVE: Videolaryngoscopes are widely used to visualize difficult airways. Our aim was to compare the GlideScope and C-MAC D-blade videolaryngoscopes for double-lumen tube (DLT) intubation in patients with difficult airways. DESIGN: A multi-center, prospective, randomized controlled trial. SETTING: Three comprehensive tertiary, high-volume hospitals from 5 December 2020 to 4 November 2021. PATIENTS: We included 348 adult patients with anticipated difficult airways who underwent elective thoracic surgery. INTERVENTIONS: Patients were randomized into two groups: GlideScope and C-MAC D-blade. Following anesthesia induction, DLT intubation was performed using different videolaryngoscopes. MEASUREMENTS: The primary outcome was the first-pass success rate of DLT intubation. All other results were recorded as secondary outcomes. MAIN RESULTS: No significant differences were observed in the first-pass success rate of DLT intubation between the GlideScope and C-MAC D-blade (86.21% and 89.66%, respectively; P = 0.323). However, compared with the GlideScope, the C-MAC D-blade provided a lower Cormack-Lehane grade (P < 0.001), lower rates of external laryngeal pressure (48 vs. 15, P < 0.001), and postprocedure sore throat (26 vs. 8, P < 0.001). The numerical rating score for difficulty of videolaryngoscope insertion into the oral cavity, delivery to the glottis, and intubation into the main bronchus were significantly lower when using the C-MAC D-blade (P < 0.001). Moreover, the duration of DLT intubation was shorter in the C-MAC D-blade group (81 s [70-97 s] vs. 95 s [78-115 s], P < 0.001). In each group, two patients underwent fiberoptic intubation after three attempts with a videolaryngoscope failed. CONCLUSIONS: In patients with difficult airways, the GlideScope and C-MAC D-blade provided a similar success rate on the first DLT intubation attempt; however, the C-MAC D-blade offers a better glottic view, easier and faster intubation, and lower incidence of sore throat.

Factors Influencing the Time of Intubation Using C-MAC D-Blade® Video Laryngoscope: An Observational Cross-Sectional Study.

Purpose C-MAC D-Blade® (Karl Storz, Tuttlingen, Germany) video laryngoscope (VL) has proved to be of immense utility in difficult intubation. But unfortunately, in an urgent situation, the predictable correct curvature of the endotracheal tube for effortless intubation is not met. We hypothesized that expertise is the most important variable in intubation and that novice students will be unable to intubate if the angle of curvature is incorrect. Methods An observational cross-sectional study was planned with 30 anesthesia residents, categorized into three groups based on their expertise in laryngoscopy. Students had to intubate an airway mannequin using the C-MAC D-Blade® VL with three different stylet angulations. The curvatures were 80, 100, and 120 degrees, which are commonly encountered in routine day-to-day practice. The time to get a stable glottic view, time to intubate, and ease of intubation were measured. Results The mean time to intubate was the least with 100-degree angulation in group C (19.60 ± 0.97) while the maximum time was in group A with 80-degree angulation (61.49 ± 3.69). A significant difference was noted in time to get a stable glottic view when compared between the groups. There was no difference in time to intubate with different stylet angulations when compared between groups. Conclusions Novices and experts could intubate even if the angle of curvature was incorrect taking more time. The time to laryngoscopy is significantly dependent on experience, but the time to intubate is influenced by the angle of curvature of the stylet.

Comparison of haemodynamic response to tracheal intubation with two different videolaryngoscopes: A randomized clinical trial.

BACKGROUND: Endotracheal intubation (ETI), which is the gold standard in coronary artery bypass grafting (CABG), may cause myocardial ischaemia by disturbing the balance between haemodynamic changes and oxygen supply and consumption of the myocardium as a result of sympathetic stimulation. In this study, we aimed to compare two different videolaryngoscopes (C-MAC and Airtraq) in the hemodynamic response to ETI. METHODS: Fifty ASA II...III CABG surgery patients were randomly assigned to C-MAC or Airtraq. The hemodynamic data included arterial blood pressure [systolic (SAP), diastolic (DAP) and mean (MAP)] and heart rate (HR) and were recorded at six different points in time: before laryngoscopy-T1, during laryngoscopy-T2, immediately after intubation-T3, and 3 (T4), 5 (T5) and 10 (T6) minutes after intubation. Intraoperative complications were recorded. Patients were questioned about postoperative complications 2 and 24...hours following extubation. RESULTS: The hemodynamic response to ETI was significantly greater with C-MAC. The increase in HR started with the laryngoscopy procedure, whereas increases in SAP, DAP, and MAP started immediately after ETI (p...=...0.024; p...=...0.012; p...=...0.030; p...=...0.009, respectively). In group analyses, T1...T2, T2...T3 and T1...T3 comparisons did not show any significant differences in HR with Airtraq. However, with C-MAC, HR after intubation increased significantly compared to the pre-laryngoscopy values (T1...T3) (p...=...0.004). The duration of laryngoscopy was significantly reduced with C-MAC (p...<...0.001), but the duration of intubation and total intubation were similar (p...=...0.36; p...=...0.79). CONCLUSIONS: Compared to C-MAC, the hemodynamic response to ETI was less with Airtraq. Thus, Airtraq may be preferred in CABG patients for ETI.

Comparison of haemodynamic response to tracheal intubation with two different videolaryngoscopes: A randomized clinical trial

Abstract Background: Endotracheal intubation (ETI), which is the gold standard in coronary artery bypass grafting (CABG), may cause myocardial ischaemia by disturbing the balance between haemodynamic changes and oxygen supply and consumption of the myocardium as a result of sympathetic stimulation. In this study, we aimed to compare two different videolaryngoscopes (C-MAC and Airtraq) in the hemodynamic response to ETI. Methods: Fifty ASA II-III CABG surgery patients were randomly assigned to C-MAC or Airtraq. The hemodynamic data included arterial blood pressure [systolic (SAP), diastolic (DAP) and mean (MAP)] and heart rate (HR) and were recorded at six different points in time: before laryngoscopy-T1, during laryngoscopy-T2, immediately after intubation-T3, and 3 (T4), 5 (T5) and 10 (T6) minutes after intubation. Intraoperative complications were recorded. Patients were questioned about postoperative complications 2 and 24hours following extubation. Results: The hemodynamic response to ETI was significantly greater with C-MAC. The increase in HR started with the laryngoscopy procedure, whereas increases in SAP, DAP, and MAP started immediately after ETI (p = 0.024; p = 0.012; p = 0.030; p = 0.009, respectively). In group analyses, T1-T2, T2-T3 and T1-T3 comparisons did not show any significant differences in HR with Airtraq. However, with C-MAC, HR after intubation increased significantly compared to the pre-laryngoscopy values (T1-T3) (p = 0.004). The duration of laryngoscopy was significantly reduced with C-MAC (p < 0.001), but the duration of intubation and total intubation were similar (p = 0.36; p = 0.79). Conclusions: Compared to C-MAC, the hemodynamic response to ETI was less with Airtraq. Thus, Airtraq may be preferred in CABG patients for ETI.

Comparison of Time to Intubation of a Double-Lumen Endobronchial Tube Utilizing C-MAC® Versus GlideScope® Versus Macintosh Blade: A Randomized Crossover Manikin Study.

BACKGROUND: Macintosh blade direct laryngoscopy is widely used for endotracheal intubation. It may, however, provide an incomplete view of the glottis in patients with challenging airway anatomy. Consequently, various video laryngoscopes have been developed to enhance the visualization of the glottis and facilitate intubation. Yet, the effectiveness of these video laryngoscopes for intubation using a double-lumen endotracheal tube (DLT), which is longer, larger, and more rigid and has a linear configuration as opposed to the naturally semicircular curvature of a single-lumen endotracheal tube, remains uncertain. We hypothesized that video laryngoscopes would be more efficient for DLT intubation compared to the Macintosh blade in an adult manikin. METHODS: Ninety-four anesthesia providers, comprising 67 residents, 15 fellows, and 12 attendings, attempted to intubate an adult manikin with normal airway anatomy (Laerdal, Wappingers Falls, NY, USA) using a 37 Fr left-sided DLT. Three different intubation devices were used: the C-MAC® video laryngoscope (Karl Storz GmbH & Co. KG, Tuttlingen, Germany), the GlideScope® video laryngoscope (Verathon Inc., Bothell, WA), and the Macintosh blade direct laryngoscope-were used. Each participant intubated a manikin once with each of the three devices. Participants were randomized via a crossover design with the order of devices determined by using a Latin square design. Time to intubation and the number of failed intubations (esophageal intubation) were compared across the three different devices. RESULTS: Mean times to intubation for the C-MAC®, GlideScope®, and Macintosh blades were 18.57 ± 0.77, 36.26 ± 2.69, and 20.76 ± 0.96 seconds, respectively. There was a statistically significant difference (P<0.001) between the GlideScope® and the other two laryngoscopes. The times for C-MAC® and Macintosh blades were not significantly different. There were two instances of first-attempt failed intubation with the Macintosh. CONCLUSION: Both the C-MAC® and the Macintosh blades proved more efficient in terms of time to DLT intubation in the manikin with normal airway anatomy, when compared to the GlideScope®. Considering the occurrence of first-attempt failed intubation, the C-MAC® was the most effective device among the three laryngoscopes for timely successful DLT intubation in the adult manikin. Further studies are needed to confirm these results in human subjects.

A randomized comparative evaluation of C-MAC video-laryngoscope with Miller laryngoscope for neonatal endotracheal intubation.

Background and Aims: An efficient neonatal airway management is peculiarly challenging even in the most experienced hands. Considering the recent interest in assessing the performance of various video-laryngoscopes (VL) in pediatric cohort, the prospective randomized study was contemplated to stage a comparative evaluation of C-MAC with Miller laryngoscope for neonatal endotracheal intubation. Material and Methods: 150 neonates were randomized to undergo intubation with either the C-MAC VL (n = 75) or the Miller laryngoscope (n = 75) performed by an experienced anesthesiologist in a tertiary care perioperative setting. The percentage of glottic opening (POGO), time to best glottic view (TTBGV), time to intubation (TTI), number of attempts, optimal external laryngeal manipulation (OELM) employed, and the complications were assessed and compared between the two groups. Results: C-MAC group demonstrated a significantly higher POGO, compared to the Miller group (88 ± 26.7%;76.8 ± 32.1%, respectively, P = 0.022). TTBGV was significantly lower in the C-MAC (7.7 ± 0.1s) group as opposed to the Miller group (11.3 ± 1.1s). The C-MAC group displayed higher TTI values compared to the Miller group (25.4 ± 1.6s; 19.7 ± 1.2s, respectively, P < 0.01). The first-attempt intubation success rate and the number of attempts were comparable in both the groups. OELM was required in 24% of the patients in the Miller group as opposed to 10.7% in the C-MAC group (P = 0.031). Higher patient percentage in the C-MAC group required the need of stylet for assisting a successful intubation, although the difference between the two groups was not statistically significant. Conclusion: Despite an improved view of the glottis, the TTI was higher for C-MAC compared to direct laryngoscopy with a comparable first-attempt success rate in the two techniques.

Comparison Between McCoy Laryngoscope and C-MAC Video Laryngoscope in Anticipated Difficult Airway: A Prospective Randomised Study.

OBJECTIVE: Prolonged laryngoscopy and failure to intubate are associated with increased morbidity and mortality. Need to improve glottic visualisation and ease of intubation has led to the introduction of various types of laryngoscopes. This study compares the effectiveness of C-MAC video laryngoscope (VL) with McCoy laryngoscope in patients with an anticipated difficult airway. METHODS: This prospective randomised single-blinded single-centre study included patients with modified Mallampati grades 3 and 4, divided into two groups I and II of 65 patients each. Group I was intubated using C-MAC and group II with McCoy Laryngoscope. Modified Cormack Lehane grade of visualisation, time to intubate, intubation difficulty scale score and complications were recorded. RESULTS: C-MAC VL provides a higher proportion of modified Cormack Lehane grade I visualisation (63% vs 35.3, p=0.0017), the lesser median time of intubation in seconds (15 vs 18, p=0.0007) and significantly lesser median intubation difficulty score (0 vs 3) when compared to McCoy. CONCLUSIONS: C-MAC VL provided better visualisation of glottis and easier tracheal intubation that too in a significantly lesser time. We conclude and recommend the use of C-MAC VL over McCoy for endotracheal intubation in patients with predicted difficult airways, especially in modified Mallampati grades 3 and 4.

Successful laryngoscope view using oversized C-Mac® D-blade in children presenting with difficult airway.

Management of the difficult paediatric airway is challenging due to anatomical differences, congenital anomalies, paucity of paediatric airway management algorithms, and the limited availability of paediatric-sized airway devices. In this case report, we describe two cases highlighting the potential use of seemingly oversized videolaryngoscopes in the management of the difficult paediatric airway. Recognising the cause of difficult airway in the paediatric population is potentially useful in the selection of a larger videolaryngoscope blade to aid laryngoscopy and intubation.

Comparative Evaluation of C-MAC Videolaryngoscope with Macintosh Direct Laryngoscope in Patients with Normal Airway Predictors.

Background: Video laryngoscopes (VL) assist in securing the airway faster and more accurately in difficult airways. However, data regarding its usefulness in patients with normal airways are sparse. Aim: We designed this study to compare the ease and success of endotracheal intubation between C-MAC and Macintosh direct laryngoscope (DL) in adult patients with no anticipated airway difficulty. Settings and Design: The design involves prospective randomized case - control study. Subjects and Methods: One hundred and twenty adult patients with predicted normal airway were randomized into two groups and were intubated using VL (C-MAC VL) and DL (Macintosh DL), respectively. The Cormack-Lehane (CL) grade, time taken for intubation, attempts taken (number), and need for laryngeal maneuvers or stylets were recorded and analyzed for statistical significance. Results: Thirty-eight patients in the DL group and 48 patients in the VL group had CL I view, 20 patients in the DL group and 16 patients in the VL group had CL II, and two patients in the DL group had CL III view. None of the patients in Group VL had CL III view. In seven out of 60 cases in the DL group, difficulty was experienced during insertion of the laryngoscope blade as compared to two cases out of 60 in the VL group. The mean time taken for intubation was lesser in Group DL (28.48 s) as compared to 39.3 s in Group VL. Nine patients in Group DL and 16 patients in Group VL required external laryngeal manipulation. Stylets were used, in seven patients in group DL and in 11 patients in group VL. Conclusions: In patients with a predicted normal airway, C-MAC provides a better glottic view compared to Macintosh DL. Time taken for intubation using the C-MAC video laryngoscope was more. However, success rates on the first attempt at endotracheal intubation and the number of intubation attempts with either laryngoscope were similar.

A Randomised Control Study Comparing C-MAC D-Blade Video Laryngoscope (Hyper Angulated Blade) and Macintosh Laryngoscope for Insertion of a Double-Lumen Tube in Patients Undergoing Elective Thoracotomy.

Background: The use of a double-lumen endotracheal tube is one of the common anesthetic techniques for operations in the thoracic cavity. However, when compared to a single-lumen tube, placement of a double-lumen tube is technically more difficult as a result of which it takes more time to insert and is associated with more complications such as mucosal injury, hoarseness, and sore throat, even in patients with no anticipated airway difficulty. The CMAC D-blade that is usually used in patients with anticipated airway difficulty, could assist in smooth and quick placement of double-lumen tube (DLT) even in patients with no anticipated airway difficulty. Aim of the Study: This study aimed to evaluate the effectiveness of the C-MAC D-blade in reducing the time taken to visualize the glottis and intubate patients with normal airway with a double-lumen tube. Setting and Design: This was a prospective open-label randomized control trial in a tertiary hospital. Materials and Methods: Seventy-three consenting adult patients with physical status classes I and II, as determined by the American Society of Anesthesiologists, scheduled to undergo elective thoracotomy, were randomly allocated to receive either C-MAC D-blade (Group D) or Macintosh blade (Group M). The primary objective was to compare the time taken for visualization of the glottis and intubation. Statistical Analysis Used: Chi-square/Fisher's exact test and t-test were used for statistical analysis. Results: Seventy-three patients were randomized (Group D = 36; Group M = 37). Time to visualize the glottic structures (4.56 ± 2.396 s vs. 7.27 ± 4.891 s, P = 0.01) was significantly better in Group D; however, the mean intubation time was comparable (55.92 ± 18.749 s vs. 51.08 ± 15.269 s, P = 0.61). Conclusion: C-MAC D-blade videolaryngoscope offers a better glottic view and lesser time to visualize glottis when compared with the Macintosh laryngoscope. However, the time taken to insert the DLT after visualization was longer. We infer that there is no advantage in the routine use of C-MAC D-blade for DLT insertion in patients with no anticipated airway difficulty.

A comparison of intubating conditions for nasotracheal intubation with standard direct Macintosh laryngoscope versus C-MAC® video laryngoscope employing cuff inflation technique in adult patients.

BACKGROUND AND AIMS: While performing laryngoscopy during nasotracheal intubation (NTI), the tip of the advancing endotracheal tube (ETT) generally lies along the posterior pharyngeal wall. The inflation of the ETT cuff brings it anterior towards the glottis. The present study was planned to compare the intubating conditions for NTI with standard direct Macintosh laryngoscope versus C-MAC® video laryngoscope (VL) employing ETT cuff inflation technique. METHODS: This prospective randomised study was carried out on 50 patients, American Society of Anesthesiologists physical status I-II, age 18-60 years of either sex with an indication for NTI under general anaesthesia. They were randomly divided into two groups: group VL (n = 25): C-MAC® VL and group ML (n = 25): Macintosh laryngoscope. The primary outcome was to compare the total duration of NTI (T), while the secondary outcomes were to compare the need for cuff inflation or assistance with Magill forceps for successful NTI, the total number of attempts to achieve successful NTI, haemodynamic effects and complications. RESULTS: T was significantly higher in group ML than group VL (P < 0.001). The intubation was successful with cuff inflation in all the patients in group VL, however, six patients of group ML required assistance with Magill forceps (P = 0.022). The haemodynamic parameters were all significantly higher at 3 min in group ML in comparison to group VL. CONCLUSION: The cuff inflation technique when used along with C-MAC® VL had more success rate, required lesser time and had minimal postoperative complications in comparison to the Macintosh laryngoscope.

Comparison of performance characteristics of C-MAC video, McCoy, and Macintosh laryngoscopes in elective cervical spine surgery.

Background and Aims: To compare the performance characteristics of C-MAC video, McCoy, and Macintosh laryngoscopes in elective cervical spine surgery. The primary objective was to assess the ease of intubation with the three study devices. The secondary objectives were the time to intubation and hemodynamic responses during intubation. Material and Methods: The prospective observational comparative study was conducted in a tertiary care hospital. Adult ASA 1 and 11 patients who underwent elective cervical spine surgery were included in the study. Patients with unstable spine and trauma were excluded. The analysis of variance, Bonferroni test, Chi square test and multiple comparison tests were used to compare the performance characteristics of laryngoscopes. Results: The C-MAC video laryngoscope improved glottis view by improving the modified Cormack-Lehane (CL) score and the percentage of glottis opening (POGO) score compared to McCoy and Macintosh laryngoscopes. The ease of intubation was better with the C-MAC video laryngoscope compared to the McCoy and Macintosh laryngoscopes. The time to intubation was comparable between the three laryngoscopes. The C-MAC video and McCoy laryngoscopes had 100% successful first attempt intubations while it was 90% for the Macintosh laryngoscope. Hemodynamic variables observed during intubation were comparable between the three groups. Conclusion: The use of C-MAC video laryngoscope resulted in better visualization of the glottis and easier tracheal intubation as compared to the Macintosh and McCoy laryngoscopes in cervical spine surgery. Both C-MAC video and McCoy laryngoscopes had 100% successful first attempt intubation.

Randomized crossover trial comparing cervical spine motion during tracheal intubation with a Macintosh laryngoscope versus a C-MAC D-blade videolaryngoscope in a simulated immobilized cervical spine.

BACKGROUND: Maintaining cervical immobilization is essential during tracheal intubation in patients with unstable cervical spines. When using the Macintosh laryngoscope for intubation in patients with cervical immobilization, substantial neck extension is required for visualization of the glottis. However, the C-MAC D-Blade videolaryngoscope may require less neck extension due to its acute angulation. We hypothesized that C-MAC D-Blade videolaryngoscopic intubation would result in less cervical spine movement than Macintosh laryngoscopic intubation. We compared the effects of C-MAC D-Blade videolaryngoscopic intubation and Macintosh laryngoscopic intubation in terms of cervical spine motion during intubation in patients with simulated cervical immobilization. METHODS: In this randomized crossover study, the cervical spine angle was measured at the occiput-C1, C1-C2, and C2-C5 segments before and during tracheal intubation with either a C-MAC D-Blade videolaryngoscope or Macintosh laryngoscope in 20 patients, with application of a neck collar for simulated cervical immobilization. Cervical spine motion was defined as the change in angle measured before and during tracheal intubation. RESULTS: The cervical spine motion at the occiput-C1 segment was measured at 12.1 ± 4.2° and 6.8 ± 5.0° during Macintosh laryngoscopic and C-MAC D-blade videolaryngoscopic intubation, respectively, corresponding to a 44% reduction in cervical spine motion when using the latter device (mean difference, - 5.3; 98.33% CI: - 8.8 to - 1.8; p = 0.001). However, there was no significant difference between the two intubation devices at the C1-C2 segment (- 0.6; 98.33% CI: - 3.4 to 2.2; p = 0.639) or C2-C5 segment (0.2; 98.33% CI: - 6.0 to 6.4; p = 0.929). CONCLUSIONS: The C-MAC D-Blade videolaryngoscope causes less upper cervical spine motion than the Macintosh laryngoscope during tracheal intubation of patients with simulated cervical immobilization. TRIAL REGISTRATION: This study was registered at ClinicalTrials.gov on June 26, 2018 ( NCT03567902 ).

GlideScope® versus C-MAC®(D) videolaryngoscope versus Macintosh laryngoscope for double lumen endotracheal intubation in patients with predicted normal airways: a randomized, controlled, prospective trial.

BACKGROUND: The double lumen endotracheal tube (DLT) is the most widely-used device for single lung ventilation in current thoracic anesthesia practice. In recent years, the routine application of the videolaryngoscope for single lumen endotracheal intubation has increased; nevertheless there are few studies of the use of the videolaryngoscope for DLT. We wondered whether there were benefits to using the videolaryngoscope for DLT placement in patients with predicted normal airways. Therefore, this study was designed to compare the performances of the GlideScope®, the C-MAC®(D) videolaryngoscope and the Macintosh laryngoscope in DLT intubation. METHODS: This was a randomized, controlled, prospective study. We randomly allocated 90 adult patients with predicted normal airways into three groups. All patients underwent routine anesthesia using different laryngoscopes according to group allocation. We compared DLT insertion times, first-pass success rates, numerical rating scales (NRS) of DLT delivery and DLT insertion, Cormack-Lehane degrees (C/L), hemodynamic changes and incidences of intubation complications. All outcomes were analyzed using SPSS13.0. RESULTS: Compared with the GlideScope, the Macintosh gave shorter times for DLT insertion (median: 96 (IQR: 51 [min-max: 62-376] s vs 73 (26 [48-419] s, p = 0.003); however, there was no difference between the Macintosh and C-MAC(D) (p = 0.610). The Macintosh had a significantly higher successful first attempt rate than did the GlideScope or C-MAC(D) (p = 0.001, p = 0.028, respectively). NRS of DLT delivery and insertion were significantly lower in the Macintosh than in the others (p < 0.001). However, the C/L degree in the Macintosh was significantly higher than in the others (p < 0.001). The incidences of oral bleeding, hoarseness, sore throat and dental trauma were low in all groups (p > 0.05). There were no significant differences in DLT misplacement, fiberoptic time or hemodynamic changes among the groups. CONCLUSIONS: Compared with the Macintosh laryngoscope, the GlideScope® and C-MAC®(D) videolaryngoscopes may not be recommended as the first choice for routine DLT intubation in patients with predicted normal airways. TRIAL REGISTRATION: The study was prospectively registered at the Chinese Clinical Trial Registry (no. ChiCTR1900025718); principal investigator: Z.L.H.; date of registration: September 6, 2019.

Comparison of conventional C-MAC video laryngoscope guided intubation by anesthesia trainees with and without Frova endotracheal introducer: A randomized clinical trial.

BACKGROUND AND AIMS: Successful intubation with video laryngoscopes necessitates good hand-eye coordination and the use of intubation adjuncts like bougie and stylet. We proposed this study to find whether using Frova introducer with C-MAC video laryngoscope will reduce the intubation time in trainee anesthesiologists. MATERIAL AND METHODS: We enrolled 140 adults without any difficult airway predictors. They were randomly assigned to undergo C-MAC video laryngoscope guided intubation by anesthesia residents using tracheal tube preloaded over Frova introducer (n = 70) or without Frova introducer (n = 70). Primary outcome was the intubation time. Secondary outcomes were the number of redirections of tracheal tube or Frova introducer toward glottis, need for external laryngeal maneuvers (ELMs), first attempt intubation success rate, and ease of intubation. RESULTS: The median actual intubation time (IQR) in Frova and non-Frova group, respectively, were 25.46 (28.11-19.80) and 19.96 (26.59-15.52) s (P = 0.001). The number of redirections of TT or Frova introducer toward glottis, first attempt success rate, and ease of intubation were comparable. The need for ELMs [n (%)] was 15 (21.4) and 26 (37.1) in Frova and non-Frova group, respectively (P = 0.04). CONCLUSION: Frova introducer guided endotracheal intubation with C-MAC videolaryngoscope in patients with normal airways had a marginally prolonged intubation time with a significant reduction in the need of external laryngeal manoeuvres but with a comparable number of redirections and attempts. Further research is needed to generalize these findings to patients with difficult airways.

Comparison of Laryngoscopic Views betweenC-MAC™ and Conventional Laryngoscopy in Patients with Multiple Preoperative Prognostic Criteria of Difficult Intubation. An Observational Cross-Sectional Study.

Background and Objectives: Video laryngoscopy has been proven useful under difficult airway scenarios, but it is unclear whether anticipated improvement of visualization is related to specific difficult intubation prognostic factors. The present study evaluated the change in laryngoscopic view between conventional and C-MAC® laryngoscopy and the presence of multiple difficult intubation risk factors. Materials and Methods: Patients scheduled for elective surgery with >2 difficult intubation factors, (Mallampati, thyromental distance (TMD), interinscisor gap, buck teeth, upper lip bite test, cervical motility, body mass index (BMI)) were eligible. Patients underwent direct laryngoscopy (DL) followed by C-MAC™ laryngoscopy (VL) and intubation. Change of view between DL and VL, time for best view, intubation difficulty scale (IDS) and correlation between prognostic factors, laryngoscopic view improvement, and IDS were measured. Results: One-hundred and seventy-six patients completed the study. VL lead to fewer Cormarck-Lehane (C/L) III-IV, compared to DL (13.6% versus 54.6%, p < 0.001). The time to best view was also shorter (VL: 10.82 s, DL: 12.08 s, p = 0.19). Mallampati III-IV and TMD ≤ 6 cm were related to improvement of C/L between DL and VL. Logistic regression showed these two factors to be a significant risk factor of the glottis view change (p = 0.006, AUC-ROC = 0.57, 95% CI: 0.47-0.66). 175/176 patients were intubated with VL. 108/176 were graded as 0 < IDS ≤ 5 and 12/176 as IDS > 5. IDS was only correlated to the VL view (p < 0.0001). Conclusion: VL improved laryngoscopic view in patients with multiple factors of difficult intubation. Mallampati and TMD were related to the improved view. However, intubation difficulty was only related to the VL view and not to prognostic factors.

Hemodynamic Response to Orotracheal Intubation: Comparison between Macintosh, McCoy, and C-MAC Video Laryngoscope.

BACKGROUND: The most commonly used devices for direct visualization of the larynx and tracheal intubation are Macintosh and McCoy laryngoscopes. C-MAC video laryngoscope, based on the principles of indirect laryngoscopy, has been introduced into clinical practice in recent years. Video laryngoscope may be useful in difficult tracheal intubation situations. AIM: We aimed at comparing the McCoy and C-MAC video laryngoscope with conventional Macintosh laryngoscope for hemodynamic responses of orotracheal intubation among adults receiving general anesthesia for elective surgeries. SETTINGS AND DESIGN: This was a hospital-based randomized, double-blind, comparison, done between June 2015 and October 2016 after permission of institutional ethical committee. MATERIALS AND METHODS: One hundred and fifty patients with normal airways undergoing elective general anesthesia were randomly allocated to undergo intubation using either Macintosh (Group A), McCoy (Group B), or C-MAC video laryngoscope (Group C). Hemodynamic changes associated with intubation were recorded immediately before and after laryngoscopy and intubation, every minute for 5 min and at 10 min after intubation by an independent observer. The time taken to perform endotracheal intubation and Cormack and Lehane score were also noted in all three groups. STATISTICAL ANALYSIS: Data were compiled, and statistical analysis was performed using SPSS 17.0 version. RESULTS: Hemodynamic response after intubation was least in Group B (McCoy) as compared to Group A (Macintosh) and Group C (C-Mac) (P = 0.001). Ninety-two percentage patients were in Cormack and Lehane score Class I in Group C in comparison to 52% in Group A and 48% in Group B (P = 0.000). Time for intubation taken in Group A, Group B, and Group C was 15.53 ± 1.53 min, 18.65 ± 0.44 min, and 22.82 ± 1.323 min, respectively (P = 0.000). CONCLUSION: The McCoy laryngoscope provided better attenuation of hemodynamic responses to laryngoscopy and intubation than the Macintosh and C-Mac video laryngoscope whereas more appearance of Cormack and Lehane score Class I was seen with the C-MAC video laryngoscope. Furthermore, the time taken to perform endotracheal intubation was the longest with the C-MAC video laryngoscope.