Percentage Of Glottic Opening Score Research Articles

Non-inferiority randomized controlled trial comparing CricOid pressure and para-laryngeal pressure in parturients undergoing cesarean delivery: NiCOP trial

BackgroundCricoid pressure has been surrounded with controversies regarding its effectiveness. Application of ultrasound-guided para-laryngeal (PL) force has been shown to occlude the esophagus effectively compared with cricoid pressure (CP) in awake patients. We hypothesized that there would be no meaningful difference in the change in antero-posterior esophageal diameter from with application of cricoid or para-laryngeal pressure in parturients undergoing cesarean delivery under general anesthesia. MethodsIn this prospective, randomized, non-inferiority trial, 40 parturients scheduled for elective cesarean delivery under general anesthesia were randomized to receive rapid sequence induction with either cricoid pressure (n = 20) or para-laryngeal pressure (n = 20). The antero-posterior diameter of the esophagus, measured by sonography, was the primary outcome. Visualization of the esophagus, its position in relation to the glottic aperture, esophageal occlusion, percentage of glottic opening (POGO), time to intubation, first pass success rate, overall success rate and adverse events like desaturation or bronchospasm were secondary outcomes. ResultsThe mean change in anterior-posterior diameter in the CP group was 0.17 ±0.1 cm vs. 0.28 ±0.1 cm in the PL group. The mean difference (CP-para-laryngeal pressure) between the groups was -0.11 (95% CI −0.17 to −0.1) cm. As the upper limit of the 95% CI was lower than the prespecified non-inferiority margin (δ = −0.2), non-inferiority was established (P <0.001]. There was no significant difference in the POGO score (P = 0.818), time to intubation (P =0.55), or intubation attempts (P = 0.99). ConclusionsPara-laryngeal pressure was non-inferior to CP in occluding the esophagus in parturients undergoing cesarean delivery under general anesthesia and furthermore, no significant deterioration in intubation parameters was seen.

Comparative Evaluation of Linscope and King Vision Video Laryngoscopes in Tracheal Intubation: A Randomized Controlled Trial.

Introduction Indirect laryngoscopy has become a widely accepted method for learning the techniques of airway management. The incorporation of small, less expensive, and yet more reliable video cameras in laryngoscopes has given the process of laryngoscopy and intubation a big leap. The King Visionvideo laryngoscope (Medline Industries, USA) has demonstrated promise in several settings while the Linscope video laryngoscope(Centrum, Turkey) is a newly launched device and no literature is available to the best of our knowledge. Therefore, we aimed to compare the performance of the Linscope video laryngoscope (VL) and King Vision video laryngoscope. Method This is a randomized controlled trial study. Seventy patients, after approval from the institute's ethical clearance, were divided into two groups. In Group A, patients were intubated with Linscope VL and in Group B patients were intubated with King Vision VL as per the protocol. The primary outcome measure was the duration of tracheal intubation. Secondary outcomes were measured by the number of attempts, ease of intubation, and glottic view. Results Both Linscope VL and King Vision VL groups were comparable in terms of mean intubation time (20.34 s vs. 19.45 s). The endotracheal intubation with both devices was 100% successful at the first attempt. Both the devices provided a percentage of glottic opening (POGO) score of > 70% and a clear vision of the glottis. The POGO score obtained with King Vision VL was 83.57 ± 11.41% and with Linscope VL was 87.85 ± 10.31%. POGO score was greater with Linscope VL compared to King Vision VL, but the difference was not statistically significant (p-value>0.05). Conclusion King Vision demonstrated shorter intubation time and fewer optimization maneuvers. Both devices achieved a 100% success rate on the first attempt. While both devices are viable first-line options, King Vision's well-established efficacy in the literature suggests its preference over Linscope till extensive evidence is available in the future.

Influence of Curved Video Laryngoscope Blade Sizes and Patient Heights on Video Laryngoscopic Views: A Randomized Controlled Trial.

This study aimed to compare the video laryngoscope views facilitated by curved blades 3 and 4 with an exploration of the relationship between these views and patient height. Conducted as a randomized controlled trial, this study enrolled adults scheduled for surgery under general anesthesia. Intubation procedures were recorded, and the percentage of glottic opening was measured before tube insertion. Multivariate analysis validated the impact of various factors, including blade size and patient height, on the percentage of glottic opening scores. A total of 192 patients were included. The median percentage of glottic opening scores for curved blades 3 and 4 were 100 and 83, respectively (p < 0.001). The unstandardized coefficient indicated a significant negative impact of blade 4 on the percentage of glottic opening scores (-13, p < 0.001). In the locally estimated scatterplot smoothing analysis, blade 3 exhibited a steady rise in glottic opening scores with increasing height, whereas blade 4 showed a peak followed by a decline around 185 cm. The unstandardized coefficient of height showed no significant association (0, p = 0.819). The study observed superior laryngoscopic views with blade 3 compared to blade 4. However, no significant association was found between laryngoscopic views and patient height.

I-gel Plus acts as a superior conduit for fiberoptic intubation than standard i-gel

The supraglottic airway (SGA) is widely used. I-gel Plus is a next-generation i-gel with some improvements, including facilitation of fiberoptic tracheal intubation (FOI). To compare the performance of i-gel Plus and standard i-gel as conduits for FOI, a Thiel-embalmed cadaveric study was conducted. Twenty-two anesthesiologists were enrolled as operators in Experiment 1. The i-gel Plus and standard i-gel were inserted into one cadaver, and the FOI was performed through each SGA. The primary outcome was time required for FOI. The secondary outcomes were the number of attempts and visual analog scale (VAS) score for difficulty in FOI. Moreover, fiberoptic views of the vocal cords in each SGA were assessed by an attending anesthesiologist using nine cadavers in Experiment 2. The percentage of glottic opening (POGO) score without fiberscope tip upward flexion and upward angle of the fiberscope tip to obtain a 100% POGO score were evaluated as secondary outcomes. The time for FOI through i-gel Plus was significantly shorter than that through standard i-gel (median (IQR), i-gel Plus: 30.3 (25.4–39.0) s, vs standard i-gel: 54.7 (29.6–135.0) s; median of differences, 24.4 s; adjusted 95% confidence interval, 3.0–105.7; adjusted P = 0.040). Although the number of attempts for successful FOI was not significantly different, the VAS score for difficulty in the i-gel Plus group was significantly lower (easier) than that in the standard i-gel group. Moreover, i-gel Plus required a significantly smaller upward angle of the fiberscope tip to obtain a 100% POGO score. FOI can be performed more easily using i-gel Plus than using standard i-gel because of the improved fiberoptic visibility of vocal cords.

Direct versus indirect epiglottis elevation in cervical spine movement during videolaryngoscopic intubation under manual in-line stabilization: a randomized controlled trial

BackgroundDuring videolaryngoscopic intubation, direct epiglottis elevation provides a higher percentage of glottic opening score than indirect epiglottis elevation. In this randomized controlled trial, we compared cervical spine movement during videolaryngoscopic intubation under manual in-line stabilization between the two glottis exposure methods.MethodsVideolaryngoscopic intubation under manual in-line stabilization was performed using C-MAC® D-blade: direct (n = 51) and indirect (n = 51) epiglottis elevation groups. The percentage of glottic opening score was set equally at 50% during videolaryngoscopic intubation in both groups. The primary outcome measure was cervical spine movement during videolaryngoscopic intubation at the occiput–C1, C1–C2, and C2–C5. The secondary outcome measures included intubation performance (intubation success rate and intubation time).ResultsCervical spine movement during videolaryngoscopic intubation was significantly smaller at the occiput–C1 in the direct epiglottis elevation group than in the indirect epiglottis elevation group (mean [standard deviation] 3.9 [4.0] vs. 5.8 [3.4] °, P = 0.011), whereas it was not significantly different at the C1–C2 and C2–C5 between the two groups. All intubations were successful on the first attempt, achieving a percentage of glottic opening score of 50% in both groups. Intubation time was longer in the direct epiglottis elevation group (median [interquartile range] 29.0 [24.0–35.0] vs. 22.0 [18.0–27.0] s, P < 0.001).ConclusionsWhen performing videolaryngoscopic intubation under manual in-line stabilization, direct epiglottis elevation can be more beneficial than indirect epiglottis elevation in reducing cervical spine movement during videolaryngoscopic intubation at the occiput–C1.Trial registrationClinical Research Information Service (number: KCT0006239, date: 10/06/2021).

Medcaptain® video laryngoscope improves nasotracheal intubation in maxillofacial surgery: A randomized clinical trial

BackgroundNasotracheal intubation may be required to secure the airway in oral and maxillofacial surgery. AimTo evaluate the effectiveness of the video laryngoscope compared with the Macintosh laryngoscope for nasotracheal intubation in maxillofacial surgery. MethodsThis prospective, randomized, single-blind trial compared the video laryngoscope with the Macintosh laryngoscope for nasotracheal intubation in the adult population.The patients were randomized into two groups: Group M, which underwent intubation with a Macintosh laryngoscope; and Group V, which underwent intubation with a video laryngoscope (Medcaptain®), using an adapted blade (no. 3 for women and no. 4 for men). The modified nasotracheal intubation difficulty scale (NIDS), the three-step evaluation of nasotracheal intubation, the Cormack–Lehane score, the percentage of glottic opening (POGO) scale, and complications were compared. ResultsIn total, 62 patients (31 in each group) were included in the study. The total intubation duration, oropharynx–glottis time, and glottis–trachea time were significantly lower in Group V compared with Group M (p = 0.001, p = 0.007, and p = 0.008, respectively). Group V also had a significantly lower NIDS score (p = 0.001), a higher POGO score (p = 0.002), and a lower Cormack–Lehane score (p = 0.034) compared with Group M. The use of Magill forceps was less frequent in Group V (p = 0.002). The two groups showed comparable results for nose–oropharynx time, epistaxis, and hoarseness (p = 0.068, p = 0.43, and p = 0.74, respectively). ConclusionVideo laryngoscopy appears to provide easier and faster nasotracheal intubation in maxillofacial surgery. Clinical trial registrationThis study was registered in the Pan African Clinical Trials Registry (PACTR) under the reference PACTR202303563303199.

Pilot Study Examining Bed Angles and Heights During Ramped Position Intubation in the Emergency Department.

Ramped positioning during emergent endotracheal intubation has been associated with fewer peri-intubation complications, including a decrease in difficult intubations, esophageal intubations, pulmonary aspiration, and hypoxemia. However, the optimal bed angle and height for ramped position intubation have not been determined. Our objective was to examine the effect bed angle and height in the ramped position may have on laryngeal views during emergent intubation in the emergency department (ED). We performed a secondary analysis of prospectively collected quality improvement data on intubations from our ED. All adult medical intubations performed with ramped positioning in the ED over a 24-month study period (September 1, 2020, through August 30, 2022) were eligible. We compared laryngeal views using the percentage of glottic opening (POGO) score between ramp angles (≥30° and <30° from horizontal) and bed heights (relative to the intubator, including xiphoid or above, umbilicus or below, and between xiphoid and umbilicus). Of the 251 patients intubated during the study period, 201 were intubated in the supine position and 50 in the ramped position. Data forms were completed for 25 patients intubated using ramped position in the ED during the study period. The median ramp angle was 30° (interquartile range (IQR) 25, 40) with 16 (64%) subjects intubated at ≥30° and 9 (36%) subjects at <30°. The median POGO scores for bed angles ≥30° and <30° were 95% (IQR 79, 100) and 90% (IQR 75, 100), respectively. Bed heights varied, with four (16%) intubated at the xiphoid or above height, one (4%) at the umbilicus or below, and 20 (80%) between the xiphoid and umbilicus. The median POGO scores at each position were 95% (IQR 76, 100), 0% (IQR 0, 0), and 95% (IQR 79, 100), respectively. ED clinicians use a variety of bed angles and heights when intubating in the ramped position. More robust investigations are necessary to determine the optimal bed angle and height for ramped position intubation in the ED.

A novel technique of handling the blade for videolaryngoscopy intubation in patients with a semi-rigid neck collar: a prospective randomized controlled trial.

Semi-rigid neck collars to protect the cervical spine can limit the extent of neck movement and mouth opening; this may further complicate orotracheal intubation. We aimed to compare intubation environments obtained with videolaryngoscopy using the technique of gliding a blade under the epiglottis and that obtained using the conventional Macintosh blade technique of blade tip placement on the vallecula. This prospective randomized study included patients aged ≥ 20 years with American Society of Anesthesiologists physical status I-III scheduled for cervical spine surgery between October 2020 and August 2021. Patients were divided into two groups according to the placement of the blade of the McGrathTM videolaryngoscope: the gliding and conventional groups. The percentage of glottic opening (POGO) score was the primary endpoint. We also recorded the time to obtain the optimal laryngoscopic view, intubation duration, and ease and satisfaction of the researcher performing intubation. Among 176 patients, the POGO scores were significantly higher in the gliding group than in the conventional group (88.9 ± 14.7 vs. 63.8 ± 27.4, P < 0.001). The time to achieve the optimal glottic view for intubation and duration of intubation were also shorter, and ease and satisfaction in performing intubation were better in the gliding group than in the conventional group. Our findings demonstrated a superior glottic view and more favorable intubation environments when the blade tip was placed under the epiglottis than using the conventional Macintosh technique in patients with immobilized cervical spine.

Efficiency, limitations, and familiarization of a novel negative pressure aerosol box for intubation: a simulation-based randomized crossover study.

This study aimed to introduce a novel negative pressure aerosol box (Carrycure Isolator) and to test its efficiency and limitations, with the hope of suggesting improvements and further directions. A novel aerosol box (Carrycure Isolator) was invented. A single-center, randomized, crossover simulation study of 28 emergency medicine physicians was designed. Three trials of each participant using an intubation manikin were conducted, including intubation without the aerosol box (trial A), intubation with the aerosol box (trial B), and intubation with the aerosol box after familiarization (trial C). The primary endpoint was the time to intubation. The secondary endpoints were first-attempt success, number of attempts, percentage of glottic opening score, and Cormack-Lehane view. Collected data were statistically analyzed for their significance. The median times to intubation of trials A, B, and C were 30.5 (interquartile range [IQR], 28.0-40.0 seconds), 59.0 (IQR, 50.0-75.5 seconds), and 34.0 seconds (IQR, 30.5-47.0 seconds), respectively. Post hoc analysis showed that the time to intubation in trial B was significantly longer than that in trial A (P<0.05), while that the time to intubation in trial C was significantly shorter than that in trial B (P<0.05). concerning secondary endpoints showed similar patterns. Participants reported performing intubation with Carrycure Isolator to be relatively difficult, necessitating significant arm movement and view restrictions while increasing their time to intubation. Physicians took a longer time to intubate a manikin using the Carrycure Isolator, a novel negative pressure aerosol box. However, the time was improved after a period of familiarization.

Comparison of C-MAC Miller blade video laryngoscope with conventional Miller blade in infants undergoing elective surgery- A prospective randomised trial.

Endotracheal intubation (ET) in infants is considered a challenging task over the decades. Infants have short safe apnoea time, and this difficulty has been vanquished to some extent by using the videolaryngoscopes (VLs), but there exists a dearth of research particularly in this vulnerable subset. Therefore, this trial was conducted to evaluate intubation times obtained with C-MAC VL and conventional Miller laryngoscopes in infants. A total of 80 infants aged between 1 month and 1 year with American Society of Anesthesiologists physical status I-II requiring ET were randomised in two groups; the C-MAC VL or Miller laryngoscope ML. Anaesthesia was induced with sevoflurane 1-8% and atracurium 0.5 mg/kg IV. The primary outcome was evaluated as the total time taken to intubate. Secondary outcomes were time to achieve best glottic view (TBGV), tube insertion time (TIT), percentage of glottic opening (POGO) score, number of attempts and intubation difficulty score (IDS). The median (interquartile range) of time taken for ET was less in VL; 22.5 (20.75-26) compared to ML; 26 (21.75-31). TBGV was achieved early in VL group than the ML group (6.03 ± 1.33s/7.88 ± 2.44) respectively (P-value < 0.001). POGO was better in VL (99.12 ± 4.795s) compared to ML (85.50 ± 31.13s). IDS was less in the VL group (0.07 ± 0.27) than in ML (0.70 ± 1.14). Other parameters, such as the number of attempts, bougie usage, adverse effects and TIT, were comparable across the two groups. When compared to the ML group, the C-MAC VL group exhibited a decreased intubation time, early TBGV, better POGO score, reduced IDS and subjective intubation difficulty. As a result, we consider VL to be a more efficacious device for intubating the trachea in infants.

Comparative evaluation of King Vision videolaryngoscope channeled and non-channeled blades with direct laryngoscope for intubation performance and skill retention by medical students: a randomized cross over two period study.

A videolaryngoscope(VL) with an intubation conduit like KingVision channeled(KVC) blade may provide an added advantage over a non-channeled VL like a KingVision non-channeled (KVNC) blade and direct laryngoscope (DL) for acquiring and retention of intubation skills, especially in novices. In this prospective two-period randomized crossover trial, one hundred medical students used three laryngoscopes KVC, KVNC and DL for intubation following standardized training with the study devices using a Laerdal Airway Management Trainer. After one month, all participants attempted intubation, in the same manner, using all devices. The duration of intubation, modified Cormack-Lehane (CL) grade, percentage of glottic opening (POGO) score, first-attempt success, number of attempts, ease of intubation and dental trauma was recorded. The retention of intubation skills after 1 month was also assessed on the same parameters. Median intubation times of KVC and DL were comparable and significantly better than KVNC (P < 0.001). The median POGO score was better with both videolaryngoscopes when compared with DL. The ease of intubation (P < 0.0012) and first-attempt success rate (P = 0.001) at the time '0' was significantly better with KVC compared to KVNC and DL. KVC fared better with respect to these intubation parameters during intubation after one month as well. KVC performed better in terms of time to intubation, success rate and ease of procedure as compared to KVNC and DL, both for acquisition and retention of skill. Hence, we advocate that KVC should be the preferred device over KVNC and DL for teaching intubation skills to novices.

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.

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. 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. 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 <CL-2b, 3), mean POGO scores without ELP (group D > group M), need for ELP and lifting force (group D < group M), and hemodynamic responses after intubation (group D < group M). 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.

Comparison of C-MAC and McGrathMAC Videolaryngoscopes for Intubation in Patients with Normal Airway by Donned Anaesthesiologists Using an Intubation Box During COVID-19 Pandemic: A Prospective, Randomized Study.

Objective:Intubation is a highly aerosol-generating procedure. Recent airway management guidelines advocate the use of appropriate personal protective equipment, videolaryngoscope, and “intubation box” while intubating a suspected or infected coronavirus patient. We undertook a study to compare C-MAC videolaryngoscope with McGrath videolaryngoscope for tracheal intubation using an intubation box by donned anaesthesiologists.Methods:The patients were randomly allocated to 2 groups by computer-generated random numbers, depending upon the videolaryngoscope used. In group C, C-MAC videolaryngoscope (n = 30) was used, whereas McGrath videolaryngoscope was used in group M (n = 30). The primary outcome was the total time required for successful intubation. The secondary outcomes included the number of attempts required, Cormack and Lehane grade, the percentage of glottis opening score, the difficulty faced while using the device, and the user’s preference.Results:The time to intubation was 57.17 ± 19.98 seconds with C-MAC videolaryngoscope as compared to 57.93 ± 14.92 seconds with McGrath. Both the devices had a good percentage of glottis opening score. Twelve patients in each group were found to have a Cormack and Lehane grade of 1. The time to glottis visualization was more with McGrath than with C-MAC although not significant (23.8 ± 14.03 vs 20.10 ± 10.78 seconds). Both the devices were easy to use.Conclusions:Both C-MAC and McGrath videolaryngoscopes are equally effective devices for intubation by a donned anaesthesiologist using an intubation box. McGrath with a disposable blade should be preferred for intubation in these conditions.

Ultrasound-guided esophageal compression during mask ventilation in small children: a prospective observational study

BackgroundThe use of cricoid compression to prevent insufflation remains controversial, and its use in children is limited. This study aimed to examine the effect of real-time ultrasound-guided esophageal compression on the prevention of gastric insufflation.MethodThis prospective observational study was conducted with fifty children aged < 2 years undergoing general anesthesia. Patients were excluded if they were at an increased risk for gastric regurgitation or pulmonary aspiration. Following anesthetic induction under spontaneous breathing, ultrasound-guided esophageal compression was performed during pressure-controlled face-mask ventilation using a gradual increase in peak inspiratory pressure from 10 to 24 cm H2O to determine the pressure at which gastric insufflation occurred. The primary outcome was the incidence of gastric insufflation during anesthetic induction with variable peak inspiratory pressure after real-time ultrasound-guided esophageal compression was applied.ResultsData from a total of 42 patients were analyzed. Gastric insufflation was observed in 2 (4.7%) patients. All patients except one had their esophagus on the left side of the trachea. Applying ultrasound-guided esophageal compression did not affect the percentage of glottic opening scores (P = 0.220).ConclusionsThe use of real-time ultrasound-guided esophageal compression pressure can aid preventing gastric insufflation during face-mask ventilation in children less than 2 years old.Trial registrationClinicaltrials.gov identifier: NCT04645043.

Comparison of time to intubate and intubation conditions with CMAC Miller blade size 1 and CMAC Macintosh blade size 2 in pediatric patients-A prospective randomized controlled study

BackgroundIntubating conditions with CMAC Miller and Macintosh blade have not been compared. AimThe primary aim was an evaluation of intubation time with a CMAC Miller blade & Macintosh blade in children. The secondary aim was an evaluation of the best glottic view time, ease of blade insertion & intubation, maneuvers and complications. MethodsA total of 160 children aged 1–4 years were included. After anesthesia, intubation was attempted with either a CMAC Miller blade size 1 (group Mil) or Macintosh blade size 2 (group Mac) by a second year resident. Intubation time, best glottic view time, procedure time, Cormack-Lehane (CL) grade, percentage of glottis opening (POGO) score, ease of blade insertion and intubation were noted. ResultsThe demographic data was comparable. Mean time for intubation (22.73 ± 9.06 vs 23 ± 8.34 s) (p = 0.84), best glottic view (11.79 ± 7.97 vs 12.66 ± 5.93 s) (p = 0.43) and procedure (28.54 ± 9.57 vs 29.24 ± 10 s) (p = 0.65) was comparable between group Mil and group Mac respectively. Ease of intubation was significantly more in group Mac (p = 0.02). The need for cheek retraction during intubation was significantly more in group Mil (p=<0.0001). The ease of blade insertion, intubation attempts, CL grading, POGO score and complications were comparable. ConclusionThe mean time for intubation was comparable with a CMAC Miller blade size 1 and Macintosh blade size 2 in 1–4 years old children. Significantly more children required cheek retraction during intubation with a Miller blade.

Effects of head-elevated position on tracheal intubation using a McGrath MAC videolaryngoscope in patients with a simulated difficult airway: a prospective randomized crossover study

BackgroundThe head-elevated laryngoscopy position has been described to be optimal for intubation, particularly in obese patients and those with anticipated difficult airways. Horizontal alignment of the external auditory meatus and sternal notch (AM-S) can be used as endpoints for optimal positioning. Thus, we aligned the head-elevated position with the AM-S in the horizontal plane and evaluated its effect on laryngeal visualization and ease of intubation using a McGrath MAC videolaryngoscope in patients with a simulated difficult airway.MethodsSixty-four patients were included in this prospective, crossover, randomized controlled trial. A cervical collar was used to restrict neck movement and mouth opening. The head-elevated position was achieved by raising the back section of the operation room table and ensuring that the end point was horizontally aligned with the AM-S (table-ramp method). The laryngeal view was randomly assessed in both head-flat and head-elevated positions based on the percentage of glottic opening (POGO) score and modified Cormack–Lehane (MCL) grade. External laryngeal manipulation was not permitted when laryngeal visualization was scored. The trachea was intubated only once (in the second position). The ease of intubation was assessed based on the need for optimization maneuvers, intubation difficulty scale (IDS) scores and time to intubation.ResultsThe mean table-ramp angle required to achieve the horizontal alignment of AM-S was 17.5 ± 4.1°. The mean POGO score improved significantly in the head-elevated position (59.4 ± 23.8%) when compared with the head-flat position (37.5 ± 24%) (P < 0.0001). MCL grade 1 or 2a was achieved in 56 (85.9%) and 28 (43.7%) of patients in the head-elevated and head-flat positions, respectively (P < 0.0001). Optimization maneuvers for intubation were required in 7 (21.9%) and 17 (53.1%) patients in the head-elevated and head-flat positions, respectively (P < 0.0001). The IDS scores and time to intubation did not differ significantly between the two positions.ConclusionIn the head-elevated position, aligning the AM-S in the horizontal plane consistently improved laryngeal visualization without worsening the view when the McGrath MAC videolaryngoscope was used in patients with simulated difficult airways. It also improved the ease of intubation, which reduced the need for optimization maneuvers.Trial registrationThis trial was registered with www.clinicaltrials.gov, NCT04716218, on 20/01/2021.

The study of head elevated position for prediction of intubation difficulty using video laryngoscope in adult patients

Background and Aim: Proper positioning of the head and neck is one of the most important steps towards laryngoscopy and tracheal intubation. We aimed to determine the effect of head elevation on the quality of laryngeal view and ease of intubation using video laryngoscopy.Method: In this prospective observational study, 100 patients who were ASA grade I/II between 18 years and 60 years with anticipated easy intubation were placed on a surgical table with non-compressible pillows under the head till horizontal alignment was achieved between the external auditory meatus and the sternal notch and the pillow height was measured. The Glottic visualization was assessed by using the modified Cormack Lehane classification and the Percentage of glottic opening (POGO) score. Intubation difficulty was assessed by the Intubation Difficulty Scale (IDS).Results: None of the patients in the study had CL Grade > 2, POGO score <50%, and IDS > 3. The mean pillow height of patients with POGO score 100% was 9.27 ± 1.27 and with POGO score 50% was 10.5 ± 1.20 (p< 0.001). Similarly, the mean pillow height of patients with CL Grade I was 9.27 ± 1.23 cm and with CL Grade II was 10.44 ± 1.20 (p< 0.001) which was highly significant. Conclusion: We concluded that alignment of the external auditory meatus and sternal notch in the horizontal plane resulted in better visualisation of the glottis and ease of intubation using a video laryngoscope. A pillow height of approximately 9cm was optimum while intubating.

Comparison of supine and upright face-to-face cadaver intubation

IntroductionOptimal patient positioning during intubation improves laryngeal view and first pass success, as well as reducing incidence of hypoxia. In certain pre-hospital situations, it may be impractical or impossible for the operator to stand behind the patient. ObjectiveWe compared intubation in the supine and upright face-to-face positions, with regards to time to intubate and the view of the vocal cords obtained. MethodsThis was a pilot comparison study. One investigator intubated 25 cadavers with the use of a bougie in the supine and upright face-to-face positions. Each attempt was recorded on a video laryngoscope. Recordings of each attempt were reviewed by five blinded emergency physicians, who allocated both a percentage of glottic opening (POGO) score and Cormack-Lehane (CL) grade. Time to insertion of the endotracheal tube (ETT) through the vocal cords was measured from the video. ResultsThe median intubation time was 1 s longer for upright cadavers than for supine cadavers, with greater variation in intubation times for upright cadavers compared with supine cadavers (IQR 9.0 vs 3.5 excluding the outlier case). The mean POGO score (averaged across raters) was 4.7% lower for upright intubation attempts (excluding the outlier case) with a moderate-to-good degree of inter-rater reliability, however this difference was not statistically significant. The median CL grade (averaged across raters) was 0.2 higher for upright intubation attempts (excluding the outlier case) with a poor-to-moderate degree of inter-rater reliability, and this difference was also not statistically significant. ConclusionsThis pilot study suggests that upright, face-to-face intubation may be clinically similar to supine intubation in terms of time to intubation and difficulty. Further studies utilising a larger number of operators and cadaver types are indicated.

Comparison of airtraq™ versus C-MAC® videolaryngoscope for tracheal intubation in children with normal airways

Background and Aims: When compared with direct laryngoscopes, videolaryngoscopes can provide a significantly better view of the larynx. There are no studies in children directly comparing Airtraq™ and C-MAC® videolaryngoscopes. We aimed to compare intubating characteristics between these two devices in pediatric patients. The primary outcome measure was the time needed for successful intubation and secondary outcome measures were the number of attempts to intubate, ease of intubation, percentage of glottic opening (POGO) score, optimization maneuvers and complications such as airway trauma and esophageal intubation. Materials and Methods: One hundred and twelve children aged 1–12 years undergoing elective surgery under general anesthesia are quiring tracheal intubation were enrolled. Children were randomized into two groups using computer generated randomization sequence. The t-test was used for analyzing quantitative data, nonparametric data were analyzed using Mann–Whitney test, and categorical data were analyzed using the Chi-square test. Results: Time to tracheal intubation was significantly longer with Airtraq™ (41.0 s) compared to C-MAC® (23.4 s); P < 0.001. The number of attempts at tracheal intubation was more with Airtraq™ (P = 0.008). Seventy-five percent of anesthesiologists found C-MAC® easy to use. POGO score was >90% in both groups without maneuvers. Conclusion: The study found that in pediatric patients with normal airways, time to intubation was faster with C-MAC® as compared to AirtraqTM. C-MAC® also performed better in aspects like the number of attempts and ease of intubation.

Comparison of double lumen tube insertion using the McGrath MAC versus direct laryngoscopy in adult patients with a limited glottis view: A prospective interventional study.

Passage of double-lumen tubes (DLT) can be challenging in patients with limited glottis view. This study aims to determine the usefulness of McGrath® MAC videolaryngoscope (VL) in cases with limited glottis view on direct laryngoscopy with Macintosh blade. After study approval and registration of trial, consent was sought from all adult patients planned for elective DLT insertion for lung isolation during the course of general anesthesia. Patients not consenting, less than 18 years, with anticipated difficult mask ventilation or need for rapid sequence induction were excluded. Following routine anesthetic induction, laryngoscopy was attempted by an experienced anesthesiologist using Macintosh scope. If the view obtained was Cormack and Lehane (CL) view IIB and above or the attempt at intubation using DLT failed despite a CL I/IIA view, the patient was included in the trial. The laryngoscope was removed and after ensuring adequate oxygenation and depth of anesthesia, intubation was attempted using McGrath® MAC VL. The percentage of glottis opening (POGO) score was noted for both the scopes. DLT insertion was attempted in 76 patients in the study period. Eight patients were included in the trial on account of limited glottis view/failure with Macintosh scope. Insertion of DLT with McGrath MAC was tried only in six patients, in two patients, the VL was not available for use. The mean (standard deviation) POGO score with Macintosh scope was 9 (±20), which significantly improved with the use of VL to 71 (±24), P = 0.01. McGrath MAC is helpful in inserting DLT in patients with limited glottis view with Macintosh scope.