Haemodynamic Response to Four Different Laryngoscopes

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

BACKGROUND

Endotracheal intubation (ETI), which is the gold standard in coronary artery bypass grafting (CABG), may cause myocardial ischaemia by disturbing the balance between haemodynamic changes and oxygen supply and consumption of the myocardium as a result of sympathetic stimulation. In this study, we aimed to compare two different videolaryngoscopes (C-MAC and Airtraq) in the hemodynamic response to ETI.

METHODS

Fifty ASA II...III CABG surgery patients were randomly assigned to C-MAC or Airtraq. The hemodynamic data included arterial blood pressure [systolic (SAP), diastolic (DAP) and mean (MAP)] and heart rate (HR) and were recorded at six different points in time: before laryngoscopy-T1, during laryngoscopy-T2, immediately after intubation-T3, and 3 (T4), 5 (T5) and 10 (T6) minutes after intubation. Intraoperative complications were recorded. Patients were questioned about postoperative complications 2 and 24...hours following extubation.

RESULTS

The hemodynamic response to ETI was significantly greater with C-MAC. The increase in HR started with the laryngoscopy procedure, whereas increases in SAP, DAP, and MAP started immediately after ETI (p...=...0.024; p...=...0.012; p...=...0.030; p...=...0.009, respectively). In group analyses, T1...T2, T2...T3 and T1...T3 comparisons did not show any significant differences in HR with Airtraq. However, with C-MAC, HR after intubation increased significantly compared to the pre-laryngoscopy values (T1...T3) (p...=...0.004). The duration of laryngoscopy was significantly reduced with C-MAC (p...<...0.001), but the duration of intubation and total intubation were similar (p...=...0.36; p...=...0.79).

CONCLUSIONS

Compared to C-MAC, the hemodynamic response to ETI was less with Airtraq. Thus, Airtraq may be preferred in CABG patients for ETI.

Curriculum and assessment tool for less invasive surfactant administration: an international Delphi consensus study

BACKGROUND

Training and assessment of operator competence for the less invasive surfactant administration (LISA) procedure vary. This study aimed to obtain international expert consensus on LISA training (LISA curriculum (LISA-CUR)) and assessment (LISA assessment tool (LISA-AT)).

METHODS

From February to July 2022, an international three-round Delphi process gathered opinions from LISA experts (researchers, curriculum developers, and clinical educators) on a list of items to be included in a LISA-CUR and LISA-AT (Round 1). The experts rated the importance of each item (Round 2). Items supported by more than 80% consensus were included. All experts were asked to approve or reject the final LISA-CUR and LISA-AT (Round 3).

RESULTS

A total of 153 experts from 14 countries participated in Round 1, and the response rate for Rounds 2 and 3 was >80%. Round 1 identified 44 items for LISA-CUR and 22 for LISA-AT. Round 2 excluded 15 items for the LISA-CUR and 7 items for the LISA-AT. Round 3 resulted in a strong consensus (99-100%) for the final 29 items for the LISA-CUR and 15 items for the LISA-AT.

CONCLUSIONS

This Delphi process established an international consensus on a training curriculum and content evidence for the assessment of LISA competence.

IMPACT

This international consensus-based expert statement provides content on a curriculum for the less invasive surfactant administration procedure (LISA-CUR) that may be partnered with existing evidence-based strategies to optimize and standardize LISA training in the future. This international consensus-based expert statement also provides content on an assessment tool for the LISA procedure (LISA-AT) that can help to evaluate competence in LISA operators. The proposed LISA-AT enables standardized, continuous feedback and assessment until achieving proficiency.

A Preliminary Feasibility Study on Hemodynamic Changes Following Feyh-Kastenbauer Retractor Insertion During Transoral Robotic Surgeries

 Introduction Transoral robotic surgery (TORS) has become increasingly popular for the removal of pharyngeal and laryngeal cancers with the objective to improve functional and aesthetic outcomes. Feyh-Kastenbauer (FK) retractor is one such routinely used retractor during TORS. The setting up of this retractor has been seen to be accompanied by hemodynamic fluctuations. Methodology This prospective observational study was carried out on 30 patients undergoing TORS. All patients were administered general anesthesia using a pre-defined anesthesia protocol. The primary outcome was to compare hemodynamic fluctuations following endotracheal intubation with that after FK retractor insertion. Any requirement of a bolus dose of sevoflurane and fentanyl was recorded in response to hemodynamic fluctuations recorded in secondary outcomes. Results There was no statistically significant increase in mean heart rate, systolic, diastolic, and mean arterial blood pressure from baseline to endotracheal intubation and following retractor insertion (p=0.810, p=0.2, p=0.6, p=0.3 respectively). On subgroup analysis, hypertensive patients reported a greater rise in blood pressure following two minutes post FK retractor insertion compared to non-hypertensive patients (p=0.03). Out of 30 patients, five patients required a bolus dose of sevoflurane. Conclusion FK retractor insertion had a comparable hemodynamic response as endotracheal intubation during TORS. Hypertensive patients showed a rise in blood pressure at both endotracheal intubations and at FK retractor insertion.

The Use of McGrath MAC Video Laryngoscope Versus McCoy Laryngoscope in Adults with Anticipated Difficult Airway Undergoing Elective Surgery

Background

Difficult airway management remains one of the most challenging clinical situations encountered by anaesthetists.

Aim

The study compared the effectiveness of the McGrath MAC video laryngoscope to the McCoy® laryngoscope in patients with difficult airway.

Materials and Methods

Following the institution's ethical approval, the randomised controlled trial was conducted involving 74 adults with American Society of anaesthesiologists' physical status (ASA) grading of I-III scheduled for elective surgery. The Patients were randomised into either group MVL (McGrath MAC) or group MCC (McCoy) and intubated after preoxygenation with 100% oxygen and administration of IV propofol and suxamethonium. The Intubation Difficulty Score (IDS), success rate of intubation, time to intubation, number of optimising manoeuvres and complications was assessed. Statistical analysis was performed using the statistical Package for Social Sciences (SPSS) version 24.0 computer software (IBM SPSS Statistics, IBM Corp. NY, United States). Numerical and categorical data were compared using the student's t-test and Chi square (χ2) test respectively. A value of P < 0.05 was considered statistically significant.

Results

Lower IDS scores were noted in the McGrath group; 54.1% vs. 5.4% of patients had IDS score of 0 in the McGrath and McCoy groups respectively, (P < 0.001). Overall success rate was higher in the McGrath group (100% vs. 89.1%), P = 0.040.

Conclusion

Lower IDS scores and improved intubation success rate was achieved with the McGrath compared with the McCoy laryngoscope in patients with predicted difficult airway. The McGrath has proved to be useful in managing patients with difficult airway.

Comparison of the stress response and intubating performance in endotracheal intubation with Macintosh and McCoy laryngoscopes

Introduction: Laryngoscopy and intubation cause stress response and sympathetic stimulation within the body. Attenuation of these changes by pharmacological means and improved technique with modified instruments is of absolute importance, for stable hemodynamics of the patients. Aim: Comparison of stress response to laryngoscopy and intubation, Intubation Difficulty Score (IDS) using Macintosh and McCoy laryngoscopes. Material and methods: After obtaining institutional ethical committee approval and patient consent in this randomized study, sixty patients of ASA grade I and II, posted for elective surgery under general anaesthesia were intubated with Macintosh or McCoy laryngoscopes. Changes in heart rate, mean arterial pressure, systolic and diastolic blood pressure were observed upto 15 minutes after laryngoscopy, along with IDS. Results: McCoy group when compared with Macintosh group had significant reduction in heart rate at T0 (p value <0.0001), systolic blood pressure at T0, T1 and T15 (p value < 0.001), diastolic blood pressure at T0, T10 and T15 (p value <0.05), mean arterial blood pressure at T0, T10 and T15 (p value <0.05) was observed in this study. Conclusion: Hemodynamic stress response with McCoy blade laryngoscope was reduced in magnitude in comparison with Macintosh blade laryngoscope.

Videolaryngoscopy versus direct laryngoscopy for adults undergoing tracheal intubation

BACKGROUND

Tracheal intubation is a common procedure performed to secure the airway in adults undergoing surgery or those who are critically ill. Intubation is sometimes associated with difficulties and complications that may result in patient harm. While it is traditionally achieved by performing direct laryngoscopy, the past three decades have seen the advent of rigid indirect videolaryngoscopes (VLs). A mounting body of evidence comparing the two approaches to tracheal intubation has been acquired over this period of time. This is an update of a Cochrane Review first published in 2016.

OBJECTIVES

To assess whether use of different designs of VLs in adults requiring tracheal intubation reduces the failure rate compared with direct laryngoscopy, and assess the benefits and risks of these devices in selected population groups, users and settings.

SEARCH METHODS

We searched MEDLINE, Embase, CENTRAL and Web of Science on 27 February 2021. We also searched clinical trials databases, conference proceedings and conducted forward and backward citation searches.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) and quasi-RCTs with adults undergoing laryngoscopy performed with either a VL or a Macintosh direct laryngoscope (DL) in any clinical setting. We included parallel and cross-over study designs.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. We collected data for the following outcomes: failed intubation, hypoxaemia, successful first attempt at tracheal intubation, oesophageal intubation, dental trauma, Cormack-Lehane grade, and time for tracheal intubation.

MAIN RESULTS

We included 222 studies (219 RCTs, three quasi-RCTs) with 26,149 participants undergoing tracheal intubation. Most studies recruited adults undergoing elective surgery requiring tracheal intubation. Twenty-one studies recruited participants with a known or predicted difficult airway, and an additional 25 studies simulated a difficult airway. Twenty-one studies were conducted outside the operating theatre environment; of these, six were in the prehospital setting, seven in the emergency department and eight in the intensive care unit.  We report here the findings of the three main comparisons according to videolaryngoscopy device type. We downgraded the certainty of the outcomes for imprecision, study limitations (e.g. high or unclear risks of bias), inconsistency when we noted substantial levels of statistical heterogeneity and publication bias. Macintosh-style videolaryngoscopy versus direct laryngoscopy (61 studies, 9883 participants) We found moderate-certainty evidence that a Macintosh-style VL probably reduces rates of failed intubation (risk ratio (RR) 0.41, 95% confidence interval (CI) 0.26 to 0.65; 41 studies, 4615 participants) and hypoxaemia (RR 0.72, 95% CI 0.52 to 0.99; 16 studies, 2127 participants). These devices may also increase rates of success on the first intubation attempt (RR 1.05, 95% CI 1.02 to 1.09; 42 studies, 7311 participants; low-certainty evidence) and probably improve glottic view when assessed as Cormack-Lehane grade 3 and 4 (RR 0.38, 95% CI 0.29 to 0.48; 38 studies, 4368 participants; moderate-certainty evidence). We found little or no clear difference in rates of oesophageal intubation (RR 0.51, 95% CI 0.22 to 1.21; 14 studies, 2404 participants) but this finding was supported by low-certainty evidence. We were unsure of the findings for dental trauma because the certainty of this evidence was very low (RR 0.68, 95% CI 0.16 to 2.89; 18 studies, 2297 participants). We were not able to pool data for time required for tracheal intubation owing to considerable heterogeneity (I2 = 96%). Hyperangulated videolaryngoscopy versus direct laryngoscopy (96 studies, 11,438 participants) We found moderate-certainty evidence that hyperangulated VLs probably reduce rates of failed intubation (RR 0.51, 95% CI 0.34 to 0.76; 63 studies, 7146 participants) and oesophageal intubation (RR 0.39, 95% CI 0.18 to 0.81; 14 studies, 1968 participants). In subgroup analysis, we noted that hyperangulated VLs were more likely to reduce failed intubation when used on known or predicted difficult airways (RR 0.29, 95% CI 0.17 to 0.48; P = 0.03 for subgroup differences; 15 studies, 1520 participants). We also found that these devices may increase rates of success on the first intubation attempt (RR 1.03, 95% CI 1.00 to 1.05; 66 studies, 8086 participants; low-certainty evidence) and the glottic view is probably also improved (RR 0.15, 95% CI 0.10 to 0.24; 54 studies, 6058 participants; data for Cormack-Lehane grade 3/4 views; moderate-certainty evidence). However, we found low-certainty evidence of little or no clear difference in rates of hypoxaemia (RR 0.49, 95% CI 0.22 to 1.11; 15 studies, 1691 participants), and the findings for dental trauma were unclear because the certainty of this evidence was very low (RR 0.51, 95% CI 0.16 to 1.59; 30 studies, 3497 participants). We were not able to pool data for time required for tracheal intubation owing to considerable heterogeneity (I2 = 99%). Channelled videolaryngoscopy versus direct laryngoscopy (73 studies, 7165 participants) We found moderate-certainty evidence that channelled VLs probably reduce rates of failed intubation (RR 0.43, 95% CI 0.30 to 0.61; 53 studies, 5367 participants) and hypoxaemia (RR 0.25, 95% CI 0.12 to 0.50; 15 studies, 1966 participants). They may also increase rates of success on the first intubation attempt (RR 1.10, 95% CI 1.05 to 1.15; 47 studies, 5210 participants; very low-certainty evidence) and probably improve glottic view (RR 0.14, 95% CI 0.09 to 0.21; 40 studies, 3955 participants; data for Cormack-Lehane grade 3/4 views; moderate-certainty evidence). We found little or no clear difference in rates of oesophageal intubation (RR 0.54, 95% CI 0.17 to 1.75; 16 studies, 1756 participants) but this was supported by low-certainty evidence. We were unsure of the findings for dental trauma because the certainty of the evidence was very low (RR 0.52, 95% CI 0.13 to 2.12; 29 studies, 2375 participants). We were not able to pool data for time required for tracheal intubation owing to considerable heterogeneity (I2 = 98%).

AUTHORS' CONCLUSIONS

VLs of all designs likely reduce rates of failed intubation and result in higher rates of successful intubation on the first attempt with improved glottic views. Macintosh-style and channelled VLs likely reduce rates of hypoxaemic events, while hyperangulated VLs probably reduce rates of oesophageal intubation. We conclude that videolaryngoscopy likely provides a safer risk profile compared to direct laryngoscopy for all adults undergoing tracheal intubation.

Video screen visualization patterns when using a video laryngoscope for tracheal intubation: A systematic review

OBJECTIVE

Published studies of video laryngoscopes are often limited by the lack of a clear definition of video laryngoscopy (VL). We performed a systematic review to determine how often published studies of VL report on video screen visualization.

METHODS

We searched PubMed, EMBASE and Scopus for interventional and observational studies in which a video laryngoscope equipped with a standard geometry blade was used for tracheal intubation. We excluded simulation based studies. Our primary outcome was data on video laryngoscope screen visualization. Secondary outcomes were explicit methodology for screen visualization.

RESULTS

We screened 4838 unique studies and included 207 (120 interventional and 87 observational). Only 21 studies (10% of 207) included any data on video screen visualization by the proceduralist, 19 in a yes/no fashion only (ie, screened viewed or not) and 2 with detail beyond whether the screen was viewed or not. In 11 more studies, visualization patterns could be inferred based on screen availability and in 16 more studies, the methods section stated how screen visualization was expected to be performed without reporting data collection on how the proceduralist interacted with the video screen. Risk of bias was high in the majority of included studies.

CONCLUSIONS

Published studies of VL, including many clinical trials, rarely include data on video screen visualization. Given the nuances of using a video laryngoscope, this is a critical deficiency, which largely prevents us from knowing the treatment effect of using a video laryngoscope in clinical practice. Future studies of VL must address this deficiency.

Split Type Postman videolaryngoscope: The newer device versus the standard Macintosh laryngoscope in simulated difficult airway – A new hope for difficult intubation scenarios

Background and Aims:

Methods:

Results:

Conclusion:

Hemodynamic Response to Laryngoscopy and Intubation Using McCoy Laryngoscope: A Descriptive Cross-sectional Study

Introduction:

Laryngoscopy and intubation are stressful as they lead to a rise in heart rate and blood pressure. Though transient, it may be detrimental to the cardiac and neurosurgical patients. There is a need to explore the possibility of obtunding the pressor response to laryngoscopy and intubation with the use of McCoy blade laryngoscope. We aimed to find out the hemodynamic response to laryngoscopy and intubation using McCoy laryngoscope in adult patients undergoing general anesthesia.

Methods:

The descriptive cross-sectional study was conducted in 37 American Society of Anesthesiologists' Physical Status I/IIpatients, with normal airway from December 2019-May 2020 in a tertiary care hospital. Ethical approval was obtained from Institutional Research Committee (reference number.: MEMG/IRC/290/GA). Convenience sampling method was used. The mean systolic and diastolic blood pressures were measured at baseline, one, three and five minutes after laryngoscopy and intubation. Data were analyzed using the Statistical Package for the Social Sciences Version 21.0.

Results:

In the first minute after laryngoscopy and intubation, the rise in mean blood pressure was noted in 14 (37.83%) cases. The peak rise in mean blood pressure was 3%, note done minute after laryngoscopy and intubation.

Conclusions:

We noted better attenuation of pressor response to laryngoscopy and intubation using McCoy blade laryngoscope in adult patients undergoing general anesthesia.

Evaluation of lightwand-guided endotracheal intubation for patients with missing or no teeth: a randomized controlled study

Background

Unhealthy teeth can seriously affect general health and increase the risk of death in elderly people. There has been no confirmation of which device is most effective for elderly patients with teeth loss. Therefore, we compared four intubation devices in elderly patients with partial and total tooth loss aiming to reduce risk during anesthesia.

Methods

Two hundred patients were randomized to undergo tracheal intubation with the Macintosh laryngoscope, the Glidescope, the Fiberoptic bronchoscope or the Lightwand as part of general anesthesia. A unified protocol of anesthetic medications was used. HR and BP were measured at T₀, T₁, T₂, T₃, T₄ and T₅. Catecholamine (epinephrine and norepinephrine) blood samples were drawn at T₀, T₁ and T₂. Intubation time and postoperative complications, including dental damage and losses, were recorded.

Results

Reduced fluctuations in HR, DBP, and SBP were observed in the Lightwand group. Intubation time was significantly shorter in the Lightwand group (p < 0.05). There was no statistically significant difference between the groups in epinephrine levels, but norepinephrine levels were less volatile in the Fiberoptic bronchoscope and Lightwand groups. Fewer patients in the Lightwand group experienced dental damage and other postoperative complications than in the other three groups. Although a higher success rate on the first attempt was as high as in the Fiberoptic bronchoscope group, shorter intubation time was observed only in the Lightwand group.

Conclusion

The Lightwand offers less hemodynamic stimulation than the Macintosh laryngoscope, Glidescope, and Fiberoptic bronchoscope. Because it had the shortest intubation time, the Lightwand caused the least damage to the teeth and throat of elderly patients. Our findings showed that tracheal intubation with the Lightwand was advantageous for preventing cardiovascular stress responses with short intubation times and fewer postoperative complications.

Utility of a Modified Oropharyngeal Airway for Performing Tracheal Intubation Using a Fiberoptic Bronchoscope and Video Stylet: A Randomized Crossover Trial Using a Manikin

Purpose

The purpose of this study was to assess if a modified airway (MA), developed by the authors, would act as a guide and improve the performance of intubation when used with a video stylet (VS) or fiberoptic bronchoscope (FOB) for endotracheal intubation.

Methods

This randomized crossover simulation study using manikins was conducted with 36 novice operators. Time to complete intubation, time to see the glottis, and success rate of intubation of each device were measured and compared with or without use of MA.

Results

For intubation using FOB with MA, the median time to complete intubation significantly reduced from 46 to 31 seconds with a medium effect size (p=0.004, r = 0.483), and the median time to see the glottis significantly reduced from 7 to 5 seconds with a medium effect size (p=0.032, r = 0.357). The overall success rate was not statistically different between FOB with MA (33/36, 91.7%) and FOB alone (31/36, 86.1%); however, the cumulative success rate over time for FOB with MA was higher than that for FOB alone (p=0.333). For intubation using VS, there were no differences in the time to see the glottis and time to complete intubation between VS with MA and VS alone (p=0.065 and p=0.926, respectively), and the cumulative success rate was not statistically significant (p=0.594).

Conclusion

Adjunct use of MA helped reduce time to complete intubation in FOB, but not in VS. If an inexperienced operator uses FOB, it would be helpful to use MA as an adjunct device.

Comparison of direct laryngoscope and McGrath videolaryngoscope in terms of glottic view and hemodynamics in bariatric surgery

Background/aim

In the recent years, videolaryngoscopes (VL) have emerged as alternative devices to direct laryngoscopes (DL) in difficult intubation situations. Therefore, we aimed to compare the Macintosh DL and McGrath VL in terms of the glottic image quality, intubation success, intubation time, hemodynamic response after intubation, and complications in bariatric surgery patients.

Material and methods

After obtaining approval by the ethics committee and receiving informed consent, we recorded the demographic and physical data of patients undergoing bariatric surgery. Patients were divided into 2 groups: Group M was intubated with the Macintosh DL, and Group V was intubated with the McGrath VL. After intubation, we noted the Cormack–Lehane score, the duration of intubation, the number of intubation interventions, and the hemodynamic data of patients.

Results

A total of 62 patients (ASA II, body mass index of >35 kg/m2) were included in the study. All patients except 1 patient were intubated on the first attempt. Although there was a decrease in heart rate and blood pressure with induction, similar hemodynamic data were obtained between groups during the operation. In group V, we obtained a better glottic image (P = 0.011), but intubation success was similar between the study groups. We also measured the intubation time in group M as 45.9 ± 19.1 s and group V as 57.1 ± 15.8 s (P = 0.015).

Discussion

Although we measured longer intubation times with the McGrath VL compared with the Macintosh DL, we obtained a better glottic image without causing hemodynamic changes. However, these findings did not make any difference in terms of intubation success.

Less invasive surfactant administration: a word of caution

Surfactant is a cornerstone of neonatal critical care, and the presumed less (or minimally) invasive techniques for its administration have been proposed to reduce invasiveness of neonatal critical care interventions. These techniques are generally known as less invasive surfactant administration (LISA) and have quickly gained popularity in some neonatal intensive care units. Despite the increase in the use of LISA, we believe that the pathobiological background supporting its possible clinical benefits is unclear. Similarly, it is unclear whether there are any ignored drawbacks, as LISA has been tested in only a few trials and some physiopathological issues seem to have gone unnoticed. Active research is warranted to fill these knowledge gaps before LISA can be firmly recommended. In this Viewpoint, we provide an in-depth analysis of LISA techniques, based on physiological and pathobiological factors, followed by a critical appraisal of available clinical data, and highlight some possible future research directions.

Tracheal intubation with the McGrath MAC X-blade videolaryngoscope in morbidly obese and nonobese patients

Background/aim

Increased body mass index (BMI) and neck circumference are the two independent predictors of difficult intubation. McGrath MAC X-Blade is a videolaryngoscope specifically designed for difficult intubations.

Materials and methods

Eighty patients with the American Society of Anesthesiologists (ASA) physical status I–III undergoing elective surgery requiring endotracheal intubation were enrolled in the study. Patients were divided into two groups, nonobese (BMI < 30) and morbidly obese (BMI > 35). All patients were intubated with the McGrath MAC X-Blade in both groups. View optimization and tube insertion maneuvers such as reinsertion of the device, slight removal of the device, cricoid pressure, handling force, 90° anticlockwise rotation of the tube, use of stylet, and head flexion maneuvers were recorded. Cormack–Lehane grades, insertion times, intubation, and total intubation times were recorded. The hemodynamic changes and postoperative minor complications were also recorded.

Results

Body mass index, neck circumference, Mallampati scores, and ASA physical status were statistically higher in the morbidly obese group (P < 0.001 and P < 0.05). Sternomental distances were shorter in the morbidly obese (P < 0.05). Cormack–Lehane grades were comparable among the groups. The morbidly obese patients required more reinsertion attempts and cricoid pressure maneuvers during intubation than the nonobese patients (P = 0.019 versus P = 0.012, respectively). Slight removal of the device, handling force, use of the stylet, 90° anticlockwise rotation of the tube, and head flexion maneuvers were also helpful in both groups. Although device insertion times were similar between the groups, intubation and total intubation times were longer in the morbidly obese group (P = 0.009 and P = 0.034, respectively). The groups were comparable in hemodynamic changes and postoperative minor complications.

Conclusion

The McGrath MAC X-Blade videolaryngoscope could safely be used both in nonobese (BMI < 30) and morbidly obese (BMI > 35) patients with the aid of some key maneuvers and with a statistically significant but clinically negligible prolongation of the intubation time.