Lehane Grade Research Articles

Determinants of Cormack–Lehane grading for glottic exposure in microlaryngeal surgery in Middle Delta Egyptian patients

BackgroundLaryngoscopy is a diagnostic procedure utilized in critical care to examine and visualize the larynx through the diversion of upper airway structures. Its primary functions are airway management and tracheal intubation. The objective of this study was to detect the predictors of laryngeal exposure during microlaryngeal surgery (MLS).MethodsAn analytical cross-sectional study was conducted on a consecutive sample of 100 patients presenting laryngeal lesions that were trans-orally microsurgeries to treat various glottic diseases (biopsies revealed 68% benign lesions such as vocal fold polyps, cysts, and nodules, and 32% glottic masses) and prepared for MLS.ResultsThis study included 100 patients presenting laryngeal lesions from both sexes with the age of 47.0 ± 14.7 years, in multivariate logistic regression analysis, all these parameters were significant predictors for Cormack–Lehane and Italian Grading (P < 0.05). Body mass index (BMI) (OR = 3.449, 95% CI = 2.463–8.187), mandibular protrusion test (OR = 2.981, 95% CI = 1.922–4.044), mento-sternal length (OR = 3.722, 95% CI = 1.980–7.794), and atlanto-occipital joint (AOJ) extension (OR = 1.572, 95% CI = 1.865–4.263). Cormack–Lehane and Italian Grading was significantly associated with BMI, mandibular protrusion test, Mallampati Index, mento-thyroid, mento-sternal length, and AOJ extension, it increased with BMI of > 35, with more protruded mandible (class C), higher Mallampati Index (class III) and shorter mento-sternal distance (≤ 12.5 cm).ConclusionsDuring microlaryngeal surgery, BMI, mandibular protrusion test, Mallampati Index, mento sternal and AOJ extension were significant predictors of Cormack–Lehane and Italian Grading which makes it easier for laryngeal exposure.

Comparison of AirAngel® vs. Storz® videolaryngoscope and Macintosh® laryngoscope for endotracheal intubation training: prospective randomized crossover study

BackgroundFor both normal and difficult airway management, VL is thought to be more effective. However, VL seems far from being offered as a standard option in both healthcare delivery and educational activities in low-income countries, considering its high costs. Therefore, three-dimensional(3D)printed VLs may be considered an alternative to conventional VLs in low-income countries and other places with limited resources. Our objective was to compare the efficacy of AirAngel 3D-printed VL (3D-PVL) with those of commercially available Storz® VL (SVL) and conventional Macintosh® laryngoscope (MCL) in normal and difficult airway scenarios in the hands of inexperienced users.MethodsThis is a prospective randomized crossover manikin study that included 126 senior medical students with no experience in intubation. The effectiveness of all three laryngoscopy devices in the hands of inexperienced users was evaluated in terms of intubation time, glottic visualization, ease of use, endotracheal tube placement, and intubation success rate. Between 2020 and 2022, 126 last year medical students participated in the study.ResultsMCL resulted in significantly longer intubation times than 3D-PVL and SVL in the difficult airway scenario, with no significant difference between 3DPVL and SVL (Wilcoxon test, p < 0.016; Bonferroni correction MCL: 28.54 s; SVL: 26.68 s; 3DPVL: 26.64 s). Both SVL and 3D-PVL resulted in significantly better Cormack − Lehane grades in both normal and difficult airway scenarios, and thus provided better glottic viewing than MCL, with no significant difference between 3D-PVL and SVL (Wilcoxon test, p < 0.016; Bonferroni correction, MCL: 1.73; SVL: 1.29; 3DPVL: 1.25). The SVL was the easiest device to use for normal airway scenarios (1: very easy, 5: very difficult), while the MCL was the most difficult (MCL: 2.64; 3DPVL: 1.98; SVL: 1.49). Conversely, no significant difference was found between 3DPVL and other devices in terms of ease of use in difficult airway scenarios and in terms of accurate placement of the endotracheal tube and successful intubation attempts.Conclusion3D-PVL is a good educational and possible clinical alternative to conventional VL, particularly in places with limited resources, due to its low cost.

Comparison of acromio-axillo-suprasternal notch index with thyromental height test to predict difficult visualization of larynx

Background: Securing and maintaining a patent airway for the conduct of general anesthesia are a major concern for an anesthesiologist. Unanticipated difficult intubation in anesthetized patients is the main cause of morbidity or mortality. Several predictors are proposed to anticipate difficult tracheal intubation, but no predictor is found to be 100% accurate. Acromio-axillo-suprasternal notch index (AASI) is a recent addition to the list of predictors. Aims and Objectives: The current study compared the usefulness of AASI and thyromental height test (TMHT) as predictors of difficult visualization of larynx (DVL). Materials and Methods: Following approval by the Institutional Ethics Committee and CTRI registration, written informed consent was taken. The study was conducted on 300 patients aged 18–65 years belonging to American Society of Anesthesiologists’ physical status I and II, with modified Mallampati (MMP) Scores of 1 and 2, over a period of 6 months. Preoperatively all patient’s airway was evaluated using AASI and TMHT. The DVL during direct laryngoscopy was noted as assessed by Cormack and Lehane grading. We compared the sensitivity and specificity for DVL with regard to AASI and TMHT. Results: The incidence of unanticipated DVL was 14%. The sensitivity, specificity, positive predictive value, and negative predictive value of AASI were 86.4%, 38.1%, 89.6%, and 31.4%, respectively, and for TMHT, they were 94.6%, 4.8%, 85.9%, and 12.5%, respectively. Pearson correlation coefficient was r = −0.068 (P=0.243) when AASI was compared with TMHT. Conclusion: AASI was found to be less sensitive when compared to TMHT and there was statistically no significant correlation between the two parameters to predict the DVL.

A comparative study of head-elevated positions at 25° versus 45° for intubation in obese patients posted for elective surgery under general anesthesia

Background: Obese patients generally present with an increased risk of difficult intubation. The head-elevated position has been shown to improve laryngeal view, reduce airway complications, and prolong safe apnea time during intubation as compared to the sniffing position. Aims and Objectives: The aim of this study is to compare the head-elevated positions at 25° versus 45° for intubation in obese patients, in terms of ease of intubation assessed by first-attempt intubation success rate and laryngeal exposure using Cormack–Lehane grading and to assess intubation time, use of intubation aides, changes in hemodynamic parameters, and hypoxia. Materials and Methods: In this randomized controlled trial, 100 consenting patients undergoing elective surgery requiring general anesthesia were selected who fulfilled the eligibility criteria and assigned to either of the two groups by block randomization: Group A – 25° or Group B – 45° head-elevated positions for intubation in a tertiary care hospital (February 2021–July 2022). Results: The 45° head-elevated position was found to provide a better laryngeal exposure, the mean time to intubate was lesser and the first attempt success rate was also higher. Further, 45° head-elevated position is better chosen as per anesthesiologist comfort, using Likert scale grading. Conclusion: This study concluded that 45° head-elevated position provides better ease of intubation in obese patients as compared to 25° head-elevation.

Comparison of different head positions for ease of intubation in obese patients using videolaryngoscopy

BackgroundIn direct laryngoscopy ramping is a recommended technique in obese patients to improve success of intubation. Recently 25° back up position has also been described for the same purpose. The effect of change in head neck positions have not been much studied in obese patients, while using videolaryngoscopy (VL). MethodsThis prospective randomized study included 150 adult obese surgical patients (BMI >30 kg/m2), requiring intubation using VL. Patients were randomly assigned one of the three groups: sniffing position, ramped up position and 25° back up position. The time taken for intubation was the primary outcome. Other parameters assessed were Cormack-Lehane grading, time to achieve best glottic view, ease and attempts required for intubation. ResultsThe study shows that, 25° back up position has reduced time taken for successful intubation 161.80 s as compared to ramped up position (172.56 s) and sniffing position (171.84 s) with p value of <0.0001. Mean time for best glottic view was 18.82 s in group C, compared to 38.24 s for group B, and 39.66 s in group A (p < 0.0001). The ease of intubation score was also very easy/easy in 9/28 patients in group C compared to 3/16 and 3/17 patients respectively in groups A and B (p = 0.007). First attempt at intubation was successful in 47 patients in group C compared to 32 and 40 patients in groups A and B respectively (p = 0.001). There was no significant difference in Cormack and Lehane grading in different positions. ConclusionsThe 25° back up position is a simple and useful technique in improving glottic view and intubation success rate with reduction in intubation time compared to ramped up and sniffing positions.

Evaluating the impact of intubation pillow on laryngoscopy grade in children: A Randomized controlled trial

Abstract Background: Laryngoscopy and intubation remain critical in pediatric patients as compared to adult patients due to different anatomy. This study was conducted to compare the Cormack and Lehane grade (CL) of laryngoscopy, percentage of glottic opening (POGO) score, and the efficacy of backward upward rightward pressure (BURP) maneuver to improve laryngoscopy grade with or without the use of intubation pillow. Subjects and Methods: A randomized controlled trial was done from January 2020 to July 2020 on 68 children with 34 children in Group 1 (with intubation pillow) and 34 patients in Group 2 (without intubation pillow). Children between 5 and 12 years of age (the American Society of Anesthesiologists class I and II) planned for surgery under general anesthesia with endotracheal tube were included in this study. Pillow of 4 cm size was used in 5–9 years and 6 cm pillow in 9–12 years of age group. Macintosh laryngoscope was used for intubation. CL grading and POGO score were assessed. BURP maneuver was given in cases of difficult laryngoscopy of CL grade above 2 and its effect on improvement in CL grading was measured. Results: Group 1 children had significantly more CL grade I (83.3% vs. 16.7%); significantly lesser CL Grade IIb (23.1% vs. 76.9%, P = 0.001); and significantly more POGO score (97% vs. 86%, P &lt; 0.05) than Group 2. The use of BURP maneuver significantly improved the laryngoscopy view in both the groups. Conclusions: The use of intubation pillow in children between 5 and 12 years of age facilitated better laryngoscopy view and POGO score.

Comparing the posture and comfort of anaesthesiologists during laryngoscopy and tracheal intubation in the head-elevated laryngoscopy position in supine position and with a 25° backup: A randomised clinical crossover trial.

The head-elevated laryngoscopy position (HELP) and a 25° backup have been proposed to enhance glottic visualisation, yet concerns about ergonomic discomfort hinder their widespread adoption. This study compares the comfort and posture adopted by anaesthesiologists while performing laryngoscopy and tracheal intubation with patients in HELP while in a supine position or with 25° backup. The study included 48 patients aged 18-60 years with normal airways and 12 experienced anaesthesiologists. Patients were randomised into two groups using permuted block randomisation. Anaesthesiologists performed laryngoscopy and intubation in supine HELP and 25° backup HELP positions. Anaesthesiologist's posture was determined by measuring the angles of neck, wrist, elbow, back and knee joints, which were compared using Student's t-test, and subjective comfort assessed on a Likert scale was compared using the Chi-square test. As mentioned by the anaesthesiologist, Cormack- Lehane grading was also noted and compared using a Chi-square test between groups, taking a P value <0.05 as significant. Both positions demonstrated comparable anaesthesiologist posture (P = 0.919) and comfort (P = 0.644). However, the 25° backup HELP positions significantly improved Cormack-Lehane grades, with 68% achieving grade 1 compared to 31% in the supine HELP group (P = 0.012). Haemodynamic stability and tracheal intubation time showed no significant differences between the groups (P = 0.475 and 0.117, respectively), and no complications were reported in either group. Anaesthesiologists' posture and comfort during laryngoscopy and tracheal intubation are similar between supine and 25° backup in patients with easy airways.

Comparison of Paraglossal Technique of Miller Blade Insertion with McCoy and Macintosh Adult Laryngoscopes on the Cormack–Lehane Grade in Patients with Simulated Restricted Neck Mobility—A Randomized Control Trial

Abstract Background The paucity in round-the-clock availability of advanced tools like flexible bronchoscopes and video laryngoscopes makes it preferable to have alternative easily available gadgets for securing the airway in patients with cervical spine injuries where head and neck movements must be strictly avoided. This study compared the paraglossal technique of Miller blade insertion with the McCoy and Macintosh laryngoscope blades on the Cormack and Lehane grading (CLG) in patients with simulated restricted neck mobility. Methods We randomized 90 patients undergoing general anesthesia to be intubated either using Miller blade (Group-Mill), McCoy blade (Group-McCoy), or Macintosh blade (Group-Mac) following neck restriction using a soft cervical collar. CLG grade, the number of intubation attempts, use of bougie, intubation time, and hemodynamic parameters were noted. Nonparametric data were compared using the chi-squared test and parametric data using one-way analysis of variance. Results Group-MILL had significantly higher patients with Grade-1 CLG compared to Group-Mac (p = 0.02). The number of attempts, use of bougie, and intubation time were, however, comparable among the three groups. The hemodynamic parameters at intubation were not significantly different among the groups. Conclusion In adult patients with simulated restricted neck, the Miller laryngoscope blade, despite providing a better laryngeal view, showed no benefit in decreasing the intubation time when compared to the McCoy or Macintosh blades.

Modified Mallampati Test in Supine versus Sitting Position as a Predictor for Difficult Intubation – An Observational Study

Abstract Background: The modified Mallampati test (MMT) is routinely employed to predict difficult laryngoscopy and tracheal intubation. This test, as a standard, when conducted with a patient in a sitting position, exhibits limited practicality due to its relatively low sensitivity and specificity in predicting difficult tracheal intubation (DTI). It is hypothesised that MMT, when performed with a patient lying supine, may improve its efficacy as a predictor of DTI. Methods: This single-centre prospective observational study was conducted involving 455 adult patients requiring general endotracheal anaesthesia. During preanaesthetic evaluation, MMT was performed in the sitting position as a standard (sitting MMT). Subsequently, independent observers recorded the MMT in the supine position (supine MMT) before administering general anaesthesia. The sitting and supine MMT were correlated with Cormack and Lehane grades using the Chi-square test. Diagnostic performance metrics, including the area under the receiver operating characteristic (ROC) curve, sensitivity, specificity, positive predictive values (PPV) and negative predictive values, were employed to assess the predictive capabilities of MMT in both positions. Results: Out of 455 patients, 72 (15.8%) experienced difficult intubation (defined as Cormack–Lehane Grade III and above). Both MMT in the sitting and supine positions demonstrated strong predictive capabilities for DTI, with areas under the ROC of 0.799 and 0.779, respectively. While sitting in the MMT position exhibited higher sensitivity (55.6% vs. 28.8%), supine MMT demonstrated a superior PPV (86.1% vs. 55.6%). Conclusion: MMT, when conducted with a patient in a supine position emerges as an alternative and a reliable predictor for predicting DTI.

Utility of ultrasonography for prediction of difficult airway and assessment of dynamic airway changes

Background: Several clinical tools are used for preoperative airway assessment. Ultrasound is an emerging tool in anesthesia, and its role in the upper airway needs to be explored. Aims and Objectives: We aimed to assess the role of airway ultrasound in predicting difficult laryngoscopy and airway changes following induction of anesthesia. Materials and Methods: Clinical airway assessment was performed with a modified Mallampati score in 100 elective surgical patients. Ultrasound variables in pre- and post-induction of anesthesia were: distance between the skin and vocal cords at the hyoid bone (DSVC hb), distance from the skin to the thyroid isthmus, distance from the skin to the tracheal ring at suprasternal notch level, and distance between the skin and the cricothyroid (DSCM). Cormack–Lehane (CL) grades 3b and 4 were classified as having a DL. Association of clinical, ultrasonography (USG) indicators and CL grading was correlated. Dynamic changes in anterior neck tissues following induction of anesthesia were also measured. Results: Pre-induction USG variables were significantly higher in the DL group compared to the NDL group (P&lt;0.05), except DSCM. Post-induction all USG parameters were significantly higher in the DL group. Among USG variables, DSVC hb and DTSI had the highest AUCs of 0.801 and 0.772, respectively. DSVC hb had a sensitivity of 76% and a specificity of 100% for DL. DTSI had a sensitivity of 92% and a specificity of 72%. There was a significant increase in depth after anesthetic induction of all USG parameters except DSCM. Conclusions: Ultrasound of anterior airway tissues can be considered for prediction of DL and allows dynamic airway assessment.

Usefulness of video laryngoscopy in tracheal intubation at thyroid surgical position for intraoperative neuromonitoring

This observational study aimed to compare the glottic view between video and direct laryngoscopy for tracheal intubation in the surgical position for thyroid surgery with intraoperative neuromonitoring. Patients scheduled for elective thyroid surgery with intraoperative neuromonitoring were enrolled. After the induction of anesthesia, patients were positioned in the thyroid surgical posture with a standard inclined pillow under their head and back. An investigator assessed the glottic view using the percentage of glottic opening (POGO) scale and the modified Cormack–Lehane grade in direct laryngoscopy and then video laryngoscopy sequentially while using the same McGRATH™ MAC video laryngoscope at once, with or without external laryngeal manipulation, at the surgical position. A total of thirty-nine patients were participated in this study. Without external laryngeal manipulation, the POGO scale significantly improved during video laryngoscopy compared to direct laryngoscopy in the thyroid surgical position (60.0 ± 38.2% vs. 22.4 ± 23.8%; mean difference (MD) 37.6%, 95% confidence interval (CI) = [29.1, 46.0], P < 0.001). Additionally, with external laryngeal manipulation, the POGO scale showed a significant improvement during video laryngoscopy compared to direct laryngoscopy (84.6 ± 22.9% vs. 58.0 ± 36.3%; MD 26.7%, 95% CI = [18.4, 35.0] (P < 0.001). The superiority of video laryngoscopy was also observed for the modified Cormack–Lehane grade. In conclusion, video laryngoscopy with the McGRATH™ MAC video laryngoscope, when compared to direct laryngoscopy with it, improved the glottic view during tracheal intubation in the thyroid surgical position. This enhancement may potentially facilitate the proper placement of the electromyography tracheal tube and prevent tube displacement due to positional change for thyroid surgery.

A comparison of the McGrath videolaryngoscope with direct laryngoscopy for rapid sequence intubation in the operating theatre: a multicentre randomised controlled trial.

Aspiration of gastric contents is a recognised complication during all phases of anaesthesia. The risk of this event becomes more likely with repeated attempts at tracheal intubation. There is a lack of clinical data on the effectiveness of videolaryngoscopy relative to direct laryngoscopy rapid sequence intubation in the operating theatre. We hypothesised that the use of a videolaryngoscope during rapid sequence intubation would be associated with a higher first pass tracheal intubation success rate than conventional direct laryngoscopy. In this multicentre randomised controlled trial, 1000 adult patients requiring tracheal intubation for elective, urgent or emergency surgery were allocated randomly to airway management using a McGrath™ MAC videolaryngoscope (Medtronic, Minneapolis, MN, USA) or direct laryngoscopy. Both techniques used a Macintosh blade. First-pass tracheal intubation success was higher in patients allocated to the McGrath group (470/500, 94%) compared with those allocated to the direct laryngoscopy group (358/500, 71.6%), odds ratio (95%CI) 1.31 (1.23-1.39); p < 0.001. This advantage was observed in both trainees and consultants. Cormack and Lehane grade ≥ 3 view occurred less frequently in patients allocated to the McGrath group compared with those allocated to the direct laryngoscopy group (5/500, 1% vs. 94/500, 19%, respectively; p < 0.001). Tracheal intubation with a McGrath videolaryngoscope was associated with a lower rate of adverse events compared with direct laryngoscopy (13/500, 2.6% vs. 61/500, 12.2%, respectively; p < 0.001). These findings suggest that the McGrath videolaryngoscope is superior to a conventional direct laryngoscope for rapid sequence intubation in the operating theatre.

Comparison of UESCOPE VL 400, I-View, Non-Channeled Airtraq Videolaryngoscopes and Macintosh Laryngoscope for Tracheal Intubation in Simulated Out-of-Hospital Conditions: A Randomized Crossover Manikin Study.

The aim of the study was to test the hypothesis that the results obtained with three different types of video laryngoscopes (UESCOPE VL-400, I-View, Non-Channeled Aitraq) with and without an endotracheal stylet should be better than the results obtained with a Macintosh laryngoscope in a simulated out-of-hospital scenario by a person without clinical experience. Primary outcome measures were the time taken to successfully achieve tracheal intubation (TI). Secondary outcomes included the grade of glottic view (Cormack and Lehane grades 1-4), the incidence of successful TI, the number of audible dental clicks indicating potential dental damage, the level of effort required to perform TI, and the operator's comfort during the procedure. The time required to achieve tracheal intubation successfully was significantly longer with the Macintosh laryngoscope and Airtraq than with the other video laryngoscopes. The use of the stylet significantly reduced the time required for tracheal intubation with the Macintosh laryngoscope (21.8 sec. vs. 24.0 sec., p = 0.026), UESCOPE VL 400 (18.1 sec. vs. 23.4 sec., p = 0.013), and Airtraq (22.7 sec. vs. 34.5 sec., p < 0.001). There were no significant differences in intubation time when using the I-View with or without stylets. No differences were observed in the Cormack-Lehane grading. The success rate of intubation was 100% for the Macintosh and I-View laryngoscopes used with or without stylets and for the UESCOPE VL 400 and Airtraq laryngoscopes used with stylets. Without stylets, the success rate of intubation was 96.6% for the UESCOPE VL 400 and 86.6% for the Airtraq. There were no significant differences in the risk of dental damage between the Macintosh, UESCOPE VL 400, I-View, and Airtraq laryngoscopes, regardless of the use of stylets (without and with stylets). The use of stylets significantly reduced dental damage only for the Airtraq laryngoscope: 8 (26.6%) vs. 2 (6.6%). Statistically significant differences in perceived exertion were observed between the mentioned laryngoscopes, both with and without stylets. However, there were no differences in the comfort of use between the laryngoscopes, regardless of the use of stylets (without and with stylets. The use of stylets led to better comfort in the case of the Macintosh (2.5 vs. 3, p = 0.043) and UESCOPE VL 400 (2 vs. 3, p = 0.008) laryngoscopes. In our study, the I-View and UESCOPE VL-400 video laryngoscopes provided better intubation results than the Macintosh laryngoscope in terms of time needed to intubate, glottis visibility, and reduction in dental damage. The use of the stylet did not significantly improve the intubation results compared to the results obtained in direct laryngoscopy. Due to the small study group and the manikin model, additional studies should be performed on a larger study group.

Topical Anaesthesia Using a Soft Mist Spray Device Allows Comfortable Awake Visualisation of the Airway via Self-Videolaryngoscopy in Volunteers.

Background: During endotracheal intubation, there is a 10% incidence of difficult laryngoscopy, which may result in serious complications. It is important to obtain as much information about the visibility of laryngeal structures before the patient is anaesthetised. Performing awake (video-) laryngoscopy on a patient is uncomfortable and can trigger gagging and coughing reflexes, making visualisation nearly impossible. The objective of this study is to evaluate the effectiveness of a soft mist spray device for airway anaesthesia during awake (video-) laryngoscopy. Methods: Twenty healthy volunteers inhaled through the Trachospray device, which was placed in their mouths. Two 2 mL syringes containing lidocaine at 4% were sprayed into the airway during inspiration. After several minutes, the subjects were asked to perform a videolaryngoscopy on themselves until the glottic structures and the vocal cords were visible. Upon completion of the procedure, all participants were asked to fill out a feedback form. Results: The duration of the videolaryngoscopy to visualisation of the vocal cords averaged 17 ± 13 s. After analysing the data, three distinct groups emerged as follows: Group 1 (70% of participants) showed no response, allowing for easy insertion of the videolaryngoscope. Group 2 (25% of participants) exhibited a light response but still permitted easy insertion and visualisation. One patient demonstrated a clear response with noticeable laryngeal contraction, requiring slightly more effort and discomfort for insertion. In 80% of the participants, the laryngeal structures were visualised according to Cormack-Lehane grade 1. All participants reported a high level of comfort, with an average rating of NRS 8. The anaesthesiologist assessed the level of anaesthesia as good to very good. No adverse events were observed. Conclusions: The Trachospray provided good, reliable, comfortable, and safe topical anaesthesia for awake videolaryngoscopy. This enables a direct visual assessment of the airway and may assist in making decisions regarding airway management for tracheal intubation.

A Comparative Exploration of Video Laryngoscopes (King Vision and Airtraq) as the Future of Intubation during General Anesthesia

Abstract Background: In the dynamic medical landscape, anesthesiology plays a pivotal role in ensuring patient safety and comfort during surgeries. Central to this is endotracheal intubation, a critical procedure for securing the airway under anesthesia. Innovations such as King Vision and Airtraq video laryngoscopes offer enhanced glottis visualization and Cormack Lehane scores compared to direct laryngoscopy, with a shorter learning curve. This study aims to assess King Vision and Airtraq’s efficiency in terms of laryngoscopy time, Cormack and Lehane grading, and single-attempt success rate, the number of intubation attempts and endotracheal intubation duration. Methodology: We conducted a study involving 90 patients, aged 20–40 years, undergoing elective surgeries in Departments of General Surgery, ENT, and Gynecology under General Anesthesia. They were divided into two groups, Group K (King Vision) and Group A (Airtraq). Anesthesiologists with at least 40 prior intubations using both devices performed intubations. Preoperative assessments included Alprazolam and Ranitidine, fasting for 8 h, and vital sign monitoring. Anesthesia induction comprised fentanyl, propofol, and succinylcholine, with Macintosh laryngoscopy as a backup. Anesthesia maintenance included nitrous oxide, oxygen, isoflurane, and rocuronium, while parameters were diligently recorded. Results: Our results indicate comparable age and gender distributions between Airtraq and King Vision groups, as well as no differences in Mallampati grading. Kings Vision showed significantly faster laryngoscopy and quicker intubation. Most patients required only one intubation attempt in both groups. Cormack and Lehane grading was unaffected by device choice. Conclusion: Our study shows that both Airtraq and King Vision perform similarly across patient characteristics, but King Vision offers faster laryngoscopy and intubation times, ideal for urgent airway management.

Comparison of TAScope (an Indigenous Videolaryngoscope) with McGrath MAC®: A Manikin Study

Background: Videolaryngoscopes are an important advancement in airway management. They are now commercially available in various designs and sizes, but are expensive. The Anaesthetist Society scope videolaryngoscope (TAScope) is an indigenously designed videolaryngoscope by a member of the anaesthesia fraternity and is economical. Before being adopted for clinical use, it is appropriate to study it rigorously. The objective of the present study was to compare the TAScope with the McGrath MAC® videolaryngoscope for time to successful intubation in an adult manikin. Methods: The present study was conducted on an adult intubation training manikin. The sequence of the use of either videolaryngoscope was chosen randomly by a computer-generated random sequence. The following parameters were noted: time of successful intubation, time required to obtain glottic view, glottic view obtained in terms of Cormack–Lehane grade and percentage of glottic opening score and number of attempts at intubation. Statistical analysis was done using SPSS version 23. Results: All intubations were successful with both videolaryngoscopes. The time for successful intubation was significantly faster with McGrath MAC® (18.31 ± 1.53 s) compared to TAScope (27.21 ± 3.03 s) (P &lt; 0.001). The time to obtain a glottic view was slightly shorter with TAScope (6.25 ± 1.78 s) compared to McGrath MAC® (6.66 ± 1.15 s). Conclusion: The time for intubation was longer with TAScope but with a similar glottic view and intubation success compared to McGrath videolaryngoscope.

A comparison of ratio of patient’s height to thyromental distance with modified mallampati test and upper lip bite test for prediction of difficult laryngoscopy

Various airway evaluation tests are performed to predict difficult intubation. The ratio of Height to thyromental distance has been reported to have a good predictability. This study tested the performance of ratio of height to thyromental distance and compared it with commonly performed airway evaluation tests: the modified Mallampati test and upper lip bite test. This descriptive study was conducted in 120 patients presenting for surgery under general anesthesia with endotracheal intubation. Preoperative airway assessment was done using Modified Mallampati test, upper lip bite test and ratio of height to thyromental distance. The Cormack and Lehane grading was done during laryngoscopy to determine easy or difficult visualization of larynx. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy of three tests were calculated. Difficult laryngoscopy was seen in 9 patients (7.5%). The sensitivity, specificity, positive predictive value, negative predictive value respectively for the tests were modified Mallampati test (22.2%, 89.2%, 14.3% and 93.4%), upper lip bite test (22.2%, 100%, 100% and 94.1%), ratio of height to thyromental distance (77.8%, 95.5%, 58.3% and 94.16%). In conclusion, we found that the ratio of patient’s height to thyromental distance performed better than MMT and ULBT in predicting difficult visualization of larynx in our population.

Systematic Review and Meta-Analysis of Randomized Controlled Trials (RCTs) Revealing the Future of Airway Management: Video Laryngoscopy vs. Macintosh Laryngoscopy for Enhanced Clinical Outcomes.

Since the 1940s, Macintosh laryngoscopy (Mac laryngoscopy) has been the gold standard for tracheal intubation, offering visualization of the glottis entrance. However, recent years have witnessed the emergence of various video laryngoscopy (VL) techniques. This systematic review and meta-analysis aims to assess the clinical outcomes of VL versus Mac laryngoscopy in an elective setting. We comprehensively searched five medical databases - PubMed, EMBASE, Medline, Cochrane Library, and Web of Science. All the databases were last searched in January 2023. We only included studies with full texts comparing VL to Mac laryngoscopy clinical outcomes. Studies were excluded if they were non-full text or non-randomized controlled trials (RCTs) and did not compare VL to Mac laryngoscopy. We extracted data comprising author names, publication year, key study outcomes (first-attempt intubation success rate, Cormack and Lehane grade, hypoxia incidence, and glottis view quality), video laryngoscope types, and sample sizes of both VL and Mac laryngoscopy groups. The Cochrane risk of bias tool was used to assess the risk of bias in the included studies. Statistical analysis was performed using Review Manager (RevMan, version 5.4;Cochrane Collaboration, London, UK), presenting results as odds ratio (OR) and risk ratios (RR) at a 95% confidence interval (CI). This facilitated the identification of relevant and appropriate studies of our analysis. The search produced 19 studies that were included in this review. The evaluated sample size ranges from 40 to 802, with 3,238 participants. The rate of success at the first attempt in the use of VL was 1,558/1,890 (82.43%), while the success rate for Mac laryngoscopy was 982/1,348 (72.85%; OR: 1.98 (1.25, 3.12)) at a 95% confidence interval. Pooled analysis indicated no significant difference for hypoxia concerning the type of device used RR (random effects: 1.02; 95% CI: 0.80-1.29). A video laryngoscope had a higher likelihood of visualizing the vocal cords categorized as category 1 in the Cormack-Lehane system of classification (RR: 2.45; 95% CI: 1.43-4.21). Additionally, considerably better glottis views were attained during VL than Mac laryngoscopy (OR: 1.77; 95% CI: 1.19-2.62). In elective tracheal intubation, VL demonstrates superior first-attempt success rates, offers improved glottis visualization, and reduces instances where the glottis cannot be viewed compared to Mac laryngoscopy.

Comparison of Disposcope endoscope with Macintosh laryngoscope for laryngoscopy

PurposeDisposcope is a novel fibreoptic intubation device that allows visualization of the glottis without aligning the oral, pharyngeal, and tracheal axes. This device may offer advantages in improving glottis exposure, or reducing hemodynamic disturbance, and minimizing movement of the upper cervical spine (C-spine). In this study, we aimed to evaluate laryngoscopy using Disposcope compared to Macintosh laryngoscope.MethodsThis study enrolled 60 adult patients (American Society of Anesthesiologists physical status 1 and 2), both male and female, underwent lumbar spine surgery, scheduled for general anesthesia with endotracheal intubation. We compared the Cormack and Lehane grade, hemodynamic response, and the maximal change in the angle between adjacent cervical vertebrae and cumulative upper C-spine movement between Disposcope and Macintosh laryngoscope. A crossover trial design was employed, with half of the patients being exposed to the glottis using the Macintosh laryngoscope first, followed by the Disposcope, and vice versa for the other half.ResultsThe intubation time in the Disposcope group was significantly lower than that in the Macintosh laryngoscope group (P < 0.01). Using the Disposcope resulted in improved views of the glottis (Z = −4.82, P < 0.01). Cormack and Lehane grade I views were achieved with the Disposcope in more patients than the Macintosh laryngoscope (36.7% versus 13.3%, P < 0.01). Grade II views were obtained in 58.3% of patients with the Disposcope, whereas a lower percentage (43.3%) was observed with the Macintosh laryngoscope. The incidence of grade III views was significantly lower with the Disposcope than with the Macintosh laryngoscope (5% versus 33.3%, P < 0.01). Additionally, there was significantly less hemodynamic disturbance (mean arterial pressure and heart rate) with the Disposcope compared to the Macintosh laryngoscope (P < 0.01). Finally, the median cumulative upper C-spine movement was greater with the Macintosh laryngoscope than with the Disposcope (26.9° versus 9.4°, P < 0.01).ConclusionsIn comparison to the Macintosh laryngoscope, the Disposcope provided improved views of the glottis and resulted in less hemodynamic disturbance and movement of the upper C-spine during laryngoscopy in patients.

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 objectiveVideolaryngoscopes 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. DesignA multi-center, prospective, randomized controlled trial. SettingThree comprehensive tertiary, high-volume hospitals from 5 December 2020 to 4 November 2021. PatientsWe included 348 adult patients with anticipated difficult airways who underwent elective thoracic surgery. InterventionsPatients were randomized into two groups: GlideScope and C-MAC D-blade. Following anesthesia induction, DLT intubation was performed using different videolaryngoscopes. MeasurementsThe primary outcome was the first-pass success rate of DLT intubation. All other results were recorded as secondary outcomes. Main resultsNo 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. ConclusionsIn 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.