Laryngoscopy Intubation Research Articles

Evaluation of laryngoscopic view, intubation difficulty and sympathetic response during direct laryngoscopy in sniffing position versus simple head extension: a clinical comparative study

Background: Proper position of the head and the neck is important for optimizing laryngoscopic view and for ease of endotracheal intubation.We compared two different positions, sniffing position and simple head extension during direct laryngoscopy on the basis of laryngoscopic view, intubation difficulty and sympathetic response. Methodology: One hundred twenty patients of age group 20-50 years, scheduled for elective surgeries under general anaesthesia were divided into two equal groups in a randomized fashion. In group A (n = 60), sniffing position during laryngoscopy and intubation; and in group B(n =60),simple head extension position during laryngoscopy and intubation. Laryngoscopy view, ease of intubation and hemodynamic parameters were recorded. Results: Demographic data and the different parameters for assessment of difficult airway were similar in both groups. Glottic visualization grade was superior in group A and intubation difficulty score were higher in Group B (P < 0.05), Hemodynamic parameters at different time intervals were comparable. Conclusion: Sniffing position during laryngoscopy was found to be superior to simple head extention position in respect of better glottis visualization and ease of intubation though no difference in sympathetic response to intubation was found.

The Utility of the C-MAC as a Direct Laryngoscope for Intubation in the Emergency Department

BackgroundAlthough the C-MAC (Karl Storz, Tuttlingen, Germany) is a video laryngoscope (VL), it can also be used as a direct laryngoscope (DL). ObjectiveThe goal of this study was to evaluate the utility of the C-MAC as a DL for intubations in the emergency department (ED). MethodsThis was an analysis of prospectively collected continuous quality-improvement data during the 6-year period from February 1, 2009 to January 31, 2015, when both the C-MAC and Macintosh DL (Mac DL) were clinically available in our ED. This analysis included adult patients who underwent rapid sequence intubation by an emergency medicine resident in the ED with a C-MAC initially used as a DL or a Mac DL. The primary outcome measure was the first pass success (FPS). ResultsWhen the C-MAC was used as a DL, the initial DL attempt was successful in 199 of 346 (57.6%) cases. When the attempt could not be completed using the C-MAC as a DL, the operator utilized the video monitor and successfully completed the intubation using VL in 104 of 134 (77.6%) cases, thus achieving an overall FPS of 303 of 346 (87.6%). When the Mac DL was used, the FPS was 505 of 671 (75.3%). ConclusionsThe C-MAC is a useful device for DL because in the event of a failed DL attempt, operators have the option of switching to the video monitor to successfully complete the intubation using VL without having to make a second attempt.

Comparison of the GlideRite to the conventional malleable stylet for endotracheal intubation by the Macintosh laryngoscope: a simulation study using manikins.

ObjectiveTo compare the effectiveness of the GlideRite stylet with the conventional malleable stylet (CMS) in endotracheal intubation (ETI) by the Macintosh laryngoscope.MethodsThis study is a randomized, crossover, simulation study. Participants performed ETI using both the GlideRite stylet and the CMS in a normal airway model and a tongue edema model (simulated difficult airway resulting in lower percentage of glottic opening [POGO]).ResultsIn both the normal and tongue edema models, all 36 participants successfully performed ETI with the two stylets on the first attempt. In the normal airway model, there was no difference in time required for ETI (TETI) or in ease of handling between the two stylets. In the tongue edema model, the TETI using the CMS increased as the POGO score decreased (POGO score was negatively correlated with TETI for the CMS, Spearman’s rho=-0.518, P=0.001); this difference was not seen with the GlideRite (rho=-0.208, P=0.224). The TETI was shorter with the GlideRite than with the CMS, however, this difference was not statistically significant (15.1 vs. 18.8 seconds, P=0.385). Ease of handling was superior with the GlideRite compared with the CMS (P=0.006).ConclusionPerformance of the GlideRite and the CMS were not different in the normal airway model. However, in the simulated difficult airway model with a low POGO score, the GlideRite performed better than the CMS for direct laryngoscopic intubation.

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

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

Comparison of the C-MAC video laryngoscope to the Macintosh laryngoscope for intubation of blunt trauma patients in the ED

ObjectivesWe aimed to compare the performance of the C-MAC video laryngoscope (C-MAC) to the Macintosh laryngoscope for intubation of blunt trauma patients in the ED. Material and methodsThis was a prospective randomized study. The primary outcome measure is overall successful intubation. Secondary outcome measures are first attempt successful intubation, Cormack–Lehane (CL) grade, and indicators of the reasons for unsuccessful intubation at the first attempt with each device. Adult patients who suffered from blunt trauma and required intubation were randomized to video laryngoscopy with C-MAC device or direct laryngoscopy (DL). ResultsDuring a 17-month period, a total of 150 trauma intubations were performed using a C-MAC and DL. Baseline characteristics of patients were similar between the C-MAC and DL group. Overall success for the C-MAC was 69/75 (92%, 95% CI 0.83 to 0.96) while for the DL it was 72/75 (96%, 95% CI 0.88 to 0.98). First attempt success for the C-MAC was 47/75 (62.7%, 95% CI 0.51 to 0.72) while for the DL it was 44/75 patients (58.7%, 95% CI 0.47 to 0.69). The mean time to achieve successful intubation was 33.4 ± 2.5 s for the C-MAC versus 42.4 ± 5.1 s for the DL (p = 0.93). There was a statistically significant difference between the DL and C-MAC in terms of visualizing the glottic opening and esophageal intubation in favor of the C-MAC (p = 0.002 and p = 0.013 respectively). Discussion and conclusionThe overall success rates were similar. The C-MAC demonstrated improved glottic view and decrease in esophageal intubation rate.

Effects of airway evaluation parameters on the laryngeal view grade in mandibular prognathism and retrognathism patients.

BackgroundFailure to maintain a patent airway can result in brain damage or death. In patients with mandibular prognathism or retrognathism, intubation is generally thought to be difficult. We determined the degree of difficulty of airway management in patients with mandibular deformity using anatomic criteria to define and grade difficulty of endotracheal intubation with direct laryngoscopy.MethodsMeasurements were performed on 133 patients with prognathism and 33 with retrognathism scheduled for corrective esthetic surgery. A case study was performed on 89 patients with a normal mandible as the control group. In all patients, mouth opening distance (MOD), mandibular depth (MD), mandibular length (ML), mouth opening angle (MOA), neck extension angle (EXT), neck flexion angle (FLX), thyromental distance (TMD), inter-notch distance (IND), thyromental area (TMA), Mallampati grade, and Cormack and Lehane grade were measured.ResultsCormack and Lehane grade I was observed in 84.2%, grade II in 15.0%, and grade III in 0.8% of mandibular prognathism cases; among retrognathism cases, 45.4% were grade I, 27.3% grade II, and 27.3% grade III; among controls, 65.2% were grade I, 26.9% were grade II, and 7.9% were grade III. MOD, MOA, ML, TMD, and TMA were greater in the prognathism group than in the control and retrognathism groups (P < 0.05). The measurements of ML were shorter in retrognathism than in the control and prognathism groups (P < 0.05).ConclusionsLaryngoscopic intubation was easier in patients with prognathism than in those with normal mandibles. However, in retrognathism, the laryngeal view grade was poor and the ML was an important factor.

Airway Management with Cervical Spine Immobilisation: A Comparison between the Macintosh Laryngoscope, Truview Evo2, and Totaltrack VLM Used by Novices--A Manikin Study.

Airway management in patients with suspected cervical spine injury plays an important role in the pathway of care of trauma patients. The aim of this study was to evaluate three different airway devices during intubation of a patient with reduced cervical spine mobility. Forty students of the third year of emergency medicine studies participated in the study (F = 26, M = 14). The time required to obtain a view of the entry to the larynx and successful ventilation time were recorded. Cormack-Lehane laryngoscopic view and damage to the incisors were also assessed. All three airway devices were used by each student (a novice) and they were randomly chosen. The mean time required to obtain the entry-to-the-larynx view was the shortest for the Macintosh laryngoscope 13.4 s (±2.14). Truview Evo2 had the shortest successful ventilation time 35.7 s (±9.27). The best view of the entry to the larynx was obtained by the Totaltrack VLM device. The Truview Evo2 and Totaltrack VLM may be an alternative to the classic Macintosh laryngoscope for intubation of trauma patients with suspected injury to the cervical spine. The use of new devices enables achieving better laryngoscopic view as well as minimising incisor damage during intubation.

Sniff to see. Comparing sniffing position versus simple head extension position for glottic exposure - A prospective, randomized cross over study

Background: Traditional teaching dictates that direct laryngoscopy is best performed with the patient's head in the sniffing position. However, of late, many authors have challenged this concept. In a recent meta-analysis, based on studies involving 2759 participants researchers have found that sniffing position affords no added advantage over simple head extension. Our study highlights an important scientific fact overlooked in all previously done studies on the subject. Aim: We aimed to compare sniffing position and simple head extension position for ease of laryngoscopic intubation using an interval scale. Materials and Methods: A prospective single-blind crossover study of 200 patients, where glottic exposure in both positions was compared in the same patient using Cormack-Lehane (CL) grading and percentage of glottic opening (POGO) score. Intubation difficulty was compared using the intubation difficulty score. Results: In every study, CL grading, an ordinal scale, has been used for comparison of glottic exposure. In our set of patients, CL grading showed 'no change' in glottic exposure quality in 85% of the laryngoscopies. When we used POGO system of classification which is an interval scale, for the same laryngoscopies in the same patients, sniffing position improved exposure in 106 patients, whereas simple head extension position improved exposure in 76 patients. Only 18 patients showed no glottic exposure. Statistical Analysis: Two-sample Wilcoxon rank-sum (Mann-Whitney) test and Chi-square tests showed sniffing position to be significantly better position for glottic exposure and for ease of intubation. Conclusion: Sniffing position provides better glottis exposure and it is easier to intubate a patient in the sniffing position as compared to simple head extension position. Sniffing position should therefore be used as initial position when attempting intubation.

Comparison of the C-MAC Videolaryngoscope and Rigid Fiberscope with Direct Laryngoscopy in Easy and Difficult Airway Scenarios: A Manikin Study

BackgroundIntubation is a fundamental skill in maintaining adequate oxygenation and ventilation of seriously ill patients. ObjectivesTo compare the C-MAC video laryngoscope and Bonfils intubation fiberscope with direct laryngoscopy in simulated easy and difficult airway scenarios. MethodsThis was a prospective, randomized-controlled cross-sectional study. Thirty emergency medicine residents attempted to intubate a manikin using four progressively more difficult airway settings (normal airway [scenario 1], cervical spine immobilization [scenario 2], cervical spine immobilization + tongue swelling scenario [scenario 3], and cervical spine immobilization + tongue swelling + limited jaw opening scenario [scenario 4]) with both the C-MAC video laryngoscope and the Bonfils intubation fiberscope and direct laryngoscope. ResultsIn the first and the second scenarios, there were no statistically significant differences between the airway devices in terms of the duration of endotracheal intubation, the viewing duration of the glottic opening, and endotracheal tube insertion time. There was no statistically significant difference between the laryngoscopes in terms of the duration of endotracheal intubation and endotracheal tube insertion time in the third scenario. The overall success rates and the viewing duration of the glottic opening were shorter with the C-MAC and Bonfils in scenarios 3 and 4. Furthermore, the duration of intubation was better with Bonfils in scenario 4. The severity of dental trauma was lowest with the Bonfils in all scenarios. The device difficulty score was greatest with the Macintosh blade, except in the normal airway scenario. The most preferred airway device was the C-MAC. ConclusionThe Bonfils and C-MAC enabled better visualization of the glottic opening when compared with the Macintosh laryngoscope.

A comparison between size 3 and 4 blades in direct laryngoscopic orotracheal intubation by incoming interns: A randomized controlled manikin study

A comparison between size 3 and 4 blades in direct laryngoscopic orotracheal intubation by incoming interns: A randomized controlled manikin study

Using Video-recorded Laryngoscopy to Evaluate Laryngoscopic Blade Approach and Adverse Events in Children.

Using recordings of endotracheal intubation attempts obtained with a video-enabled laryngoscope with Miller and Macintosh blades, the authors sought to evaluate the association between laryngoscopic approach (right-sided vs. midline) and intubation success, as well as adverse event rates in the pediatric emergency department (ED). This was a retrospective cohort study of children younger than 21 years who underwent endotracheal intubation with a C-MAC video laryngoscope in a tertiary care ED between August 2009 and May 2013. The primary outcome was successful endotracheal intubation on the first attempt. The secondary outcomes included time to intubation, video-recorded adverse events (oropharyngeal mucosal injury and aspiration), and physiologic adverse events. Multivariate regression models were used to determine the relationship between laryngoscope blade position and outcome measures adjusted for patient and provider factors. The cohort consisted of complete video recordings for 105 of 143 (73%) patient encounters with intubations. The first-pass success rate did not significantly differ based on laryngoscopic approach (adjusted odds ratio [aOR] = 0.76, 95% confidence interval [CI] = 0.29 to 2.0). Among patients successfully intubated on the first attempt, the median time to intubation was longer for the right-sided approach compared to the midline approach (42 seconds vs. 31.5 seconds; p < 0.05). The odds of mucosal injury and aspiration were higher among patients intubated using a right-sided approach compared to a midline approach (aOR = 4.1, 95% CI = 1.2 to 14.5; aOR = 7.7, 95% CI = 1.5 to 39.5, respectively). Rates of physiologic adverse events did not differ based on approach. First-pass success rate did not differ based upon laryngoscopic approach type; however, a right-sided approach was associated with a longer time to intubation, as well as higher rates of mucosal injury and aspiration among patients undergoing video-enabled intubation in a pediatric ED.

The reflective intubation manoeuvre increases success rate in moderately difficult direct laryngoscopy: A prospective case-control study.

Reflective intubation is a recently described technique to facilitate tracheal intubation. The aim of the study was to assess success rate of reflective intubation in patients undergoing tracheal intubation and to correlate its application with laryngeal visibility. A prospective case-control study. Operating theatre suite of a university hospital. One hundred randomly selected patients undergoing elective surgery who required tracheal intubation as part of standard anaesthesia care. All patients underwent an initial intubation attempt using conventional direct laryngoscopy. Successfully intubated patients formed group E (easy), and the remaining patients underwent a single reflective intubation attempt. Patients with successful reflective intubation formed group M (moderate). The remaining patients underwent tracheal intubation using a suitable alternative intubation technique (group D, difficult). Primary outcomes were the success rate and time to successful intubation. Laryngeal visibility scores, changes in arterial oxygen saturation and incidence of sore throat were secondary outcomes. Forty-six patients underwent successful tracheal intubation using conventional laryngoscopy (group E), 42 patients presented moderate difficulty (group M) and 12 patients required alternative intubation techniques (group D). Reflective intubation was successful in 78% of patients in the 'noneasy' subgroup, but was unsuccessful in 22%. Intubation times were 9 ± 3 (group E), 15 ± 9 (group M) and 46 ± 38 s (group D). Oxygen saturation was comparable in all patients. Sore throat occurred significantly more often in group D. Reflective intubation proved to be successful in moderately difficult intubation conditions (Cormack and Lehane classes 2 and 3a). Reflective intubation represents a very useful first-line methodological extension of direct laryngoscopic tracheal intubation.

Management and maintenance of the airway in cervical necrotising fasciitis: a retrospective analysis of 15 cases

Cervical necrotising fasciitis is a progressive deep infection of the neck associated with high mortality, and skillful management of the airway is critical for operations under general anaesthesia. Tracheostomy under local anaesthesia has been considered the gold standard of airway management in patients with deep neck infections, but it may be difficult or impossible in advanced cases. We report here our experience over 6 years (January 2008 and December 2013) during which a total of 15 patients was diagnosed with cervical necrotising fasciitis. Of 6 patients, admitted between January 2008 and March 2010, 5 had routine tracheostomy under local anaesthesia, 1 had direct laryngoscopy intubation, and 9 who were admitted between Spring 2010 and December 2013 were treated with nasotracheal intubation. Postoperatively all patients were given moderate sedation and analgesia. Nasotracheal intubation was continued until the infection had been controlled. During intubation patency of the endotracheal tube was maintained by humidification with a continuous pump of 0.45% sodium chloride and suction. All 15 patients (10 men and 5 women, mean age 62 years, range 36-93) required an emergency drainage procedure under general anaesthesia. Fourteen of the 15 had evidence of compromise of the airway, but emergency intervention was not required. Since Spring 2010, 9 consecutive patients had required nasotracheal intubation, including 7 video laryngoscopies and 2 fibreoptic bronchoscopies. No other interventions were required. Patients were intubated postoperatively from 3 to 14 days, and there were no problems with the airway. Advanced techniques for control of the airway have a high rate of success in patients with necrotising fasciitis and could be an appropriate alternative to a traditional airway. Postoperative sedation and analgesia should be considered as routine management of pain and anxiety.

A randomized comparison of the Laryngoscope with Fiber Optic Reusable Flexible Tip English Macintosh blade to the conventional Macintosh laryngoscope for intubation in simulated easy and difficult child airway with chest compression scenarios

IntroductionWe hypothesized that the Laryngoscope with Fiber Optic Reusable Flexible Tip English Macintosh blade (TMAC) is beneficial for the intubation of child manikins while performing cardiopulmonary resuscitation (CPR). In the present study, we evaluated the effectiveness of the conventional Macintosh laryngoscope (MAC) and TMAC in 3 simulated CPR scenarios. MethodsA randomized crossover simulation trial was designed. One hundred seven paramedics intubated the trachea of a PediaSIM CPR training manikin (FCAE HealthCare, Sarasota, FL) using the MAC and TMAC in a normal airway scenario (scenario A), normal airway with chest compression scenario (scenario B), and difficult airway with chest compression scenario (scenario C). The participants were directed to make a maximum of 3 attempts in each scenario. The success rate, time required for intubation, Cormack-Lehane grade, dental compression, and the ease of intubation were measured. ResultsThe median time of intubation with MAC and TMAC in scenario A was 19.6 (interquartile range [IQR], 18-23) vs 19 (IQR, 16.2-21.8); in scenario B, 29.5 (IQR, 25-31) vs 26 (IQR, 23.5-29) seconds; and in scenario C, 38 (IQR, 32.5-45) vs 29 (IQR, 25-31) seconds, respectively. The overall efficacy for each of the scenarios was as follows: in scenario A, it was 100% vs 100%; in scenario B, it was 79.4% vs 100% (P = .007); and in scenario C, it was 68.2% vs 90.7% (P < .001), respectively. ConclusionsThe TMAC seems to be a superior intubating device compared with the conventional MAC when used in simulated normal and difficult child airway with chest compression scenarios. Future studies should explore the efficacy of TMAC in pediatric clinical emergency settings.

Comparison of Macintosh laryngoscope and C-MAC video laryngoscope for intubation in lateral position.

Background and Aims:Endotracheal intubation is conventionally performed when the patient is in supine position. It may be required to secure airway in laterally positioned patient. Tracheal intubation in lateral position seems to be difficult because the laryngeal view is compromised. Hence, C-MAC video laryngoscope (Karl Storz, Germany), a newer device using a modified macintosh blade may be useful for intubation in lateral position.Material and Methods:A total of 100 American Society of Anesthesiologists Grade I and II patients, randomly allotted to C-MAC or direct laryngoscopy group. Patients with difficult airway were excluded. After induction of anesthesia, patient was put in right-lateral position and intubation was carried out by consultant who is well-versed in using C-MAC laryngoscope. Time for intubation, number of attempts, Modified Cormack – Lehane grade, mucosal injury, and external laryngeal manipulation applied were noted.Statistical Analysis:Demographics and baseline airway assessments were analyzed using summary statistics. Unpaired t-test was used to assess intubation time. Number of attempts, esophageal intubation, dental injury, mucosal injury, use of stylet, and application of external laryngeal manipulation were analyzed using Chi-square test.Results:Overall intubation success rate was 100%. The time taken in C-MAC group was 24.8 ± 8.5 s and in direct group was 33.8 ± 9.12 s. The number of intubation attempts was not significant. Cormack – Lehane grade was better with C-MAC laryngoscope. Mucosal injury and use of external laryngeal manipulation was more in direct group.Conclusion:C-MAC is better than Macintosh laryngoscope for intubation in lateral position.

Hemodynamic responses to endotracheal intubation: A comparison between Bonfils intubation fiberscope and direct laryngoscopy

Background: Laryngoscopy and intubation are intensely stimulating procedures and can induce marked sympathetic responses. We hypothesized that by minimizing the oropharyngeal stimulus with Bonfils rigid fiberscope intubation, the hemodynamic responses to endotracheal intubation will be lesser. Therefore, we compared Bonfils intubation with conventional direct laryngoscopic intubation in adult patients with normal airway. Materials and Methods: Sixty adult patients of either sex, belonging to American Society of Anesthesiologists grade 1 or 2, were randomized into Bonfils group and laryngoscopy group, and studied over a 2-year period. Anesthet ic technique was standardized in both the groups. Hemodynamic variables were recorded at pre-induction, induction, post-induction at laryngoscopy and intubation, thereafter for every minute for 10 min, and half hourly till the end of surgery for both the groups. Intubation time, intubation attempts, and postoperative complications like hoarse voice and sore throat were compared between the two groups. Results: There was no statistically significant difference between the two groups with respect to systolic blood pressure, mean blood pressure, and heart rate changes throughout the study period. There was a statistically significant difference in the diastolic blood pressure (DBP) values between the groups (P < 0.05) for the first 10 min following intubation. The time required for intubation was significantly longer in the Bonfils group (36 ± 6 s) compared to the laryngoscopy group (28 ± 6 s) (P = 0.000). The incidence of postoperative sore throat (P = 0.009) and hoarseness of voice (P = 0.045) was significantly lesser in the Bonfils group compared to the laryngoscopy group. Conclusion: There was no clinically significant difference in the hemodynamic changes following intubation using either Bonfils fiberscope or conventional laryngoscope. Bonfils intubation required longer time, but was associated with lesser incidence of sore throat and hoarseness of voice when compared to laryngoscopic intubation.

Anesthetic Management for Laser Excision of Ball-Valving Laryngeal Masses

A 47-year-old obese woman with GERD and COPD presents for CO2-laser excision of bilateral vocal fold masses. She had a history of progressive hoarseness and difficulty in breathing. Nasopharyngeal laryngoscopy revealed large, mobile, bilateral vocal cord polyps that demonstrated dynamic occlusion of the glottis. We describe the airway and anesthetic management of this patient with a topicalized C-MAC video laryngoscopic intubation using a 4.5 mm Xomed Laser Shield II endotracheal tube. We examine the challenges of anesthetic management unique to the combined circumstances of a ball-valve lesion and the need for a narrow-bore laser compatible endotracheal tube.

Comparison of the C-MAC D-Blade, Conventional C-MAC, and Macintosh Laryngoscopes in Simulated Easy and Difficult Airways.

Recently, to further enhance the potential in the management of difficult airways, the highly angulated D-Blade was added to the C-MAC system. The purpose of this study was to investigate the laryngoscopic view and intubation parameters using the new C-MAC D-Blade in comparison to the conventional C-MAC video laryngoscope and Macintosh direct laryngoscope in simulated easy and difficult airways. We recruited 26 experienced anaesthesia providers into a randomized trial. Each performed tracheal intubation of a Laerdal SimMan(®) manikin with each laryngoscope in the following laryngoscopy scenarios: (1) normal airway, (2) cervical spine immobilization, and (3) tongue edema. The intubation times, success rates, number of intubation attempts, laryngoscopic views, and severity of dental compression were recorded. In all scenarios, video laryngoscopes provided better laryngeal exposure than the ML and appeared to produce less dental pressure. In the cervical spine immobilization scenario, D-Blade caused less dental pressure and showed better Cormack-Lehane (CL) classes than the other devices (p<0.001). There were no differences between video laryngoscopes in success of tracheal intubation (p>0.05). The CMAC provided the most rapid intubation. The rate of failure was 19% with ML. In the tongue edema scenario, the CMAC provided the most rapid and successful intubation (p<0.001). There were no differences between video laryngoscopes in laryngoscopic views according to CL classification and dental pressure (p>0.05). The rate of failure was 46% with the ML and 7% with the D-Blade. The CMAC D-Blade caused less dental pressure than the conventional C-MAC and ML in the cervical immobilization scenario. The conventional CMAC performed better than the D-Blade and ML in the tongue edema scenario. These two video laryngoscopes may complement each other in various difficult airway situations.

A Comparative Study of Tracheal Intubation Characteristics Using Macintosh and Airtraq Laryngoscope

Background: Direct laryngoscopy for endotracheal intubation with the Macintosh blade is most commonly used for establishing a patent airway. Airtraq Tm Optical Laryngoscope, does not require the alignment of the 3 airway axes for glottic visualization. Objective: We aim to compare these two laryngoscopes in view of laryngoscopic grading, ease of tracheal intubation and hemodynamic changes associated with laryngoscopy and intubation. Materials and Methods: 50 ASA I and II patients were randomly divided into Macintosh (M) group and Airtraq (A) group. Cormack Lehane grading, ease of intubation, laryngeal intubation time in secs and incidence of sore throat was noted. HR&BP was recorded at 0, 1, 3, 5&10 minutes following intubation. Unpaired 't' test compared inter-group data, while paired 't' test compared within group cardiovascular data. (p<0.05 statistically significant). Results: The demographic data of both groups were comparable. Cormack-Lehane grading was better in group A than in group M [grade I group A(84%) and group M(60%)]. The mean time for laryngeal intubation (Mean ± SD) for group A (8.3 ± 4.6 secs) and group M (20.46 ± 6.6 secs) (t = 7.6, p< 0.01). Ease of intubation was better in group A than group M. The rise in blood pressure and heart rate was significantly less in Group A as compared to Group M. Conclusion: Airtraq laryngoscope was superior to Macintosh laryngoscope as it provided better laryngoscopic views, shorter laryngoscopy and intubation time, easier intubation and the rise in heart rate and systolic blood pressure was significantly less.

English

Laryngoscopy and endotracheal intubations are frequently conducted in general anesthesia. However, it can stimulate symphatic and sympatoadrenal activities. Several non and pharmacological interventions have been used to reduce the symphatic stimulation. Fentanyl is one of the opioid drugs that frequently used to decrease the cardiovascular responses after the intubations. In order to obtain an optimal effect, fentanyl should be administered in appropriate time. This study was conducted to compare the time of fentanyl administration at 2, 5 and 7 minutes before endotracheal intubation to reduce hemodynamic responses. This was an obervational study with a prospective cohort design on patients who were going to undergo elective sugical using general anesthesia followed laryngoscopy intubation in Dr Sardjito General Hospital and met the inclusion and exclusion criteria. The patients were then divided into 3 groups i.e patients who received fentanyl 1.5 μg/kg body weight (BW) intravenously (IV) 2 minutes (Group A), 5 minutes (Group B) and 7 minutes (Group C) before laryngoscopy intubations. The hemodynmic responses including sistolic and diastolic blood pressure (SBP and DBP), mean arterial pressure (MAP), heart rate (HR) and rate pressure product (RPP) were monitored and recorded every 1 minute during 7 minutes period. The result showed that fentanyl administration 5 minutes before laryngeal intubation was more effective in the decrease hemodynamic response that those 2 and 7 minutes. Significantly different in SBP in 2, 3, 4 and 7 minutes observations was observed (p&lt;0.05). Furthermore, significantly different in MAP in 2, 3 and 4 minutes observation and in RPP in 1, 2, 3, 4 and 7 minute observation were also observed (p&lt;0.05). No significantly different was observed in HR during observation (p&gt;0.05). In conclusion, the administration of fentanyl 1.5 μg/kg BW IV at 5 minutes before intubation is more effective against hemodynamic responses in endotracheal intubation.