Blind Intubation through Self-pressurized, Disposable Supraglottic Airway Laryngeal Intubation Masks

Pharyngolaryngeal Morbidity With the Laryngeal Mask Airway SupremeTM at Different Fiberoptic Bronchoscopy Grades: An Observational Study

OBJECTIVE

To assess whether the different fiberoptic bronchoscopy (FOB) grades of laryngeal mask airway (LMA) Supreme™ affects pharyngolaryngeal morbidity (PLM, including sore throat, dysphonia, pharyngoxerosis, and dysphagia) after general anesthesia.

METHODS

A total of 235 adult patients scheduled for elective laser lithotripsy undergoing general anesthesia with the placement of LMA Supreme™ were enrolled. The position of LMA Supreme™ was assessed by FOB and categorized into five grades. Meanwhile, patients were divided into four groups (grades A-D); none was assessed as grade E. We collected blinded data on PLM at 2 (H+2), 6 (H+6), and 24 hours (H+24) postoperatively. The incidence and severity of PLM as the primary outcome and incidence of PLM at three time points as a secondary outcome were compared.

RESULTS

The incidence of PLM was higher at 2 and 6 hours than at 24 hours; however, no significant difference was found between the incidence of PLM in the FOB groups. Furthermore, the severity of sore throat and dysphonia between groups were obviously differed at H+6 and H+24, but similar at H+2. The severity of postoperative pharyngoxerosis and dysphagia were similar between groups at three time points.

CONCLUSIONS

A positive association was found between the severity of postoperative sore throat and dysphonia and FOB grade after LMA Supreme™ placement. PLM secondary to placement of the LMA Supreme™ was short lasting.

Association Between Age- and Sex-Specific Body Mass Index Percentile and Multiple Intubation Attempts: A Retrospective Cohort Analysis

BACKGROUND

Obesity distorts airways and slightly complicates intubations in adults, but whether obesity complicates pediatric intubations remains unclear. We, therefore, tested the primary hypothesis that increasing age- and sex-specific body mass index (BMI) percentile is associated with difficult intubation, defined as >1 intubation attempt.

METHODS

We conducted a retrospective analysis of pediatric patients between 2 and 18 years of age who had noncardiac surgery with oral endotracheal intubation. We assessed the association between BMI percentile and difficult intubation, defined as >1 intubation attempt, using a confounder-adjusted multivariable logistic regression model. Secondarily, we assessed whether the main association depended on preoperative substantial airway abnormality status or age group.

RESULTS

A total of 9339 patients were included in the analysis. Median [quartiles] age- and sex-specific BMI percentile was 70 [33, 93], and 492 (5.3%) patients had difficult intubation. There was no apparent association between age- and sex-specific BMI percentile and difficult intubation. The estimated odds ratio (OR) for having difficult intubation for a 10-unit increase in BMI percentile was 0.98 (95% confidence interval [CI], 0.95-1.005) and was consistent across the 3 age groups of early childhood, middle childhood, and early adolescence (interaction P = .53). Patients with preoperative substantial airway abnormalities had lower odds of difficult intubation per 10-unit increase in BMI percentile, with OR (95% CI) of 0.83 (0.70-0.98), P = .01.

CONCLUSIONS

Age- and sex-specific BMI percentile was not associated with difficult intubation in children between 2 and 18 years of age. As in adults, obesity in children does not much complicate intubation.

New Devices, Innovative Technologies, and Non-Standard Techniques for Airway Management: A Narrative Review

A wide range of airway devices and techniques have been created to enhance the safety of airway management. However, airway management remains a challenge. All techniques are susceptible to failure. Therefore, it is necessary to have and know the greatest number of alternatives to treat even the most challenging airway successfully. The aim of this narrative review is to describe some new devices, such as video laryngeal masks, articulated stylets, and non-standard techniques, for laryngeal mask insertion and endotracheal intubation that are not applied in daily practice, but that could be highly effective in overcoming a difficulty related to airway management. Artificial intelligence and 3D technology for airway management are also discussed.

Application of visual placement of a nasojejunal indwelling feeding tube in intensive care unit patients receiving mechanical ventilation

Background

Compared with nasogastric nutrition, nasojejunal nutrition may prevent some complications of critically ill patients by maintaining better nutritional status, and blind placement of nasojejunal dwelling feeding tubes is widely used. However, the visual placement seems to be safer and more effective than the blind placement, and is still seldom reported.

Objective

We tried to develop visual placement of a nasojejunal feeding tube in intensive care unit patients.

Methods

A total of 122 patients receiving mechanical ventilation were admitted to the Department of Critical Care Medicine of the Fifth Affiliated Hospital of Wenzhou Medical University and received the placement of nasojejunal feeding tubes. These patients were randomly and evenly assigned into two groups, one group receiving visual placement of nasojejunal dwelling feeding tubes and another group receiving blind placement. Actual tube placement was confirmed by X-ray. The primary outcome included the success rates of first placement of feeding tubes. The secondary outcome included the time of tube placement, complications, the total cost, heart rates and respiratory rates.

Results

The primary outcome showed that the success rates of first placement were 96.70% (59 cases/61 cases) in the visual placement group, and two cases failed due to pyloric stenosis and gastroparesis. The success rates were 83.6% (51 cases/61 cases) in the blind placement group and 10 cases failed due to either wrong placement or retrograde tube migration. The success rates in the visual placement group were higher than that in the blind placement group (P = 0.015). The secondary outcome showed that the time of tube placement in the visual placement group was shorter than that in the blind placement group (P < 0.0001). The cost of tube placement in the visual placement group was higher than that in the blind placement group (P < 0.0001). The statistical differences in complications, heart and respiratory rates were insignificant between the two groups (P > 0.05).

Conclusion

Compared with the blind placement, the visual placement shortened the time of nasojejunal tube placement and increased success rates of first placement. The visual placement was more efficient, easy to operate, safe, and has potential clinical applications.

Tracheal intubation using intubating laryngeal tube iLTS-D™ and LMA Fastrach™ in 99 adult patients: A prospective multicentric randomised non-inferiority study

STUDY OBJECTIVE

This study aimed to investigate the overall success of tracheal intubation using the intubating Laryngeal Tube Suction-Disposable (iLTS-D™, VBM, Sulz a. N., Germany) compared to the Laryngeal Mask Airway (LMA) Fastrach™ (Teleflex, Athlone, Ireland). We hypothesised that the iLTS-D™ would be non-inferior to the LMA Fastrach™ for tracheal intubation and ventilation.

DESIGN

Multicentric, non-inferiority, randomised controlled study.

SETTING

Operating rooms from two tertiary and one secondary centre in Switzerland from January 2017 to July 2019. The investigators were trained anaesthetists with extensive experience with laryngeal masks but limited to laryngeal tubes. The study was discontinued after the planned interim analysis.

PATIENTS

Ninety-nine adult patients were included after randomisation. The inclusion criteria were American Society of Anesthesiologists physical status 1 to 3 in patients scheduled for elective surgery requiring tracheal intubation. Patients with a history of difficult intubation were excluded.

INTERVENTION(S)

After anaesthesia induction and once neuromuscular blockade was obtained, ventilation was initiated, and tracheal intubation was performed through the randomised device with the flexible endoscope tip placed proximally to the tip of the tracheal tube (visualised blind intubation).

MEASUREMENTS

The primary outcome was the intubation success rate after two attempts. The secondary outcomes were time to intubation, successful ventilation rate, time to achieve ventilation, and gastric access success rate.

MAIN RESULTS

The overall intubation success rate was significantly higher in the Fastrach™ group than in the iLTS-D™ group (91.8% vs 70.0%, p = 0.006). No difference was found in the ventilation success rate (94% for iLTS-D™ and 100% for LMA Fastrach™ [p = 0.829]). The time to achieve ventilation and intubation were similar between the groups. No major airway complications were noted.

CONCLUSIONS

Although both supraglottic devices provided the same effective ventilation rate, the LMA Fastrach™ was superior to the iLTS-D™ as a conduit for intubation in 99 adult patients without a known difficult intubation. These preliminary results need to be confirmed in studies that include a larger population.

TRIAL REGISTRATION

Clinicaltrials.gov, 21.09.2016, Identification Number NCT02922595.

Emergency Surgery in the Elderly: Could Laparoscopy Be Useful in Frailty? A Single-Center Prospective 2-Year Follow-Up in 120 Consecutive Patients

Background: the general population is aging across the world. Therefore, even surgical interventions in the elderly—in particular those involving emergency surgical admissions—are becoming more frequent. The elderly population is often frail (in multiple physiological systems, this is often defined as age-related cumulative decline). This study involved a 2-year follow-up evaluation of frail elderly patients treated with urgent surgical intervention at Santa Maria Regina della Misericordia Hospital, General Surgery Department, in Adria (Italy). Method: a prospective, single-center, 2-year follow-up study of 120 patients >65 years old, treated at our department for surgical abdominal emergencies. We considered co-morbidities (ASA—American Society of Anesthesiologists Physical Status Classification System—score), type of surgery (laparoscopy, laparotomy or converted), frailty score, mortality, and complications at 30 days and at 2 years. Conclusions: 70 (58.4%) patients had laparoscopy, 49 (40.8) had laparotomy, and in 1 (0.8%) case, surgery was converted from laparoscopy to laparotomy. Mortality strictly depends on the type of surgery (laparotomy vs. laparoscopy), complications during recovery, and a lower Fried frailty criteria score, on average. The long-term follow-up can be a useful tool to highlight a safer surgical approach, such as laparoscopy, in frail elderly patients. We consider the laparoscopic approach feasible in emergency situations, with similar or better outcomes than laparotomy, especially in frail elderly patients.

Macintosh Videolaryngoscope for Intubation in the Operating Room: A Comparative Quality Improvement Project

BACKGROUND

"Macintosh"-videolaryngoscopes (VLs) are VLs that allow both direct and indirect laryngoscopy for intubation. We describe the decision-making and implementation-processes that our hospital used regarding the choice of device. We compared the performances of 4 Macintosh-VLs both in direct and indirect laryngoscopy.

METHODS

A quality-improvement-project for airway management aiming at implementing Macintosh-VL for all intubation procedures performed in the operating room, involving 4 Macintosh-VLs (McGrath-Mac, C-MAC-S, C-MAC-S-Pocket-Monitor [PM], and APA). Three consecutive steps were described: (1) direct laryngoscopy with Macintosh-VL, (2) indirect laryngoscopy with Macintosh-VL (intubation attempt with Macintosh-style blade in case of Cormack I or II), (3) intubation attempt with hyperangulated blade in case of Cormack III/IV or failure of Macintosh-style blade. The main end point was the need to move to step III and use a hyperangulated blade. A mixed-effects multivariable logistic regression analysis was performed to compare devices on the main end point while considering site as a random effect. Comparison of means was performed using analysis of variance and Tukey's test for multiple comparisons (number of laryngoscopy attempts, numeric rate scale [NRS] difficulty of intubation and NRS user-friendliness). Comparison of percentages was performed using a χ2 test for the need to move to step III and a Kruskal-Wallis test for the quality of image (bad, passable, good, very good, excellent). A P value ≤.008 was considered statistically significant.

RESULTS

From May to September 2017, 589 patients were included. Using the McGrath-Mac (22/180 [12%]) was associated with less use of hyperangulated blade than using the C-MAC-S (39/132 [30%], odds ratio [OR] [99.2% confidence interval {CI}] 0.34 [0.16-0.77], P = .0005), the APA (35/138 [25%], OR [99.2% CI] 0.42 [0.19-0.93]; P = .004), but not the C-MAC-S-PM (29/139 [21%], OR [99.2% CI] 0.53 [0.23-1.2]; P = .04).Overall, the number of intubation attempts was significantly lower using the McGrath Mac than the C-MAC-S or the C-MAC-S-PMVLs. Subjective appreciation of intubation difficulty and user-friendliness of the devices showed respectively lower and higher NRS scores for the McGrath-Mac compared to the other devices, whereas subjective assessment of image quality showed higher quality for the C-MAC-S and C-MAC-S-PM compared to the APA or McGrath-Mac.

CONCLUSIONS

Among 4 single-use Macintosh-VLs, glottic visualization in direct and indirect laryngoscopy with the Macintosh-style blade was significantly improved with the McGrath-Mac compared to other Macintosh-VLs, leading to a less frequent need to resort to the hyperangulated blade and reduced overall number of intubation attempts.

McGrath Video Laryngoscope Versus Macintosh Direct Laryngoscopy for Intubation of Morbidly Obese Patients: A Randomized Trial

BACKGROUND

Two-thirds of the US population is considered obese and about 8% morbidly obese. Obese patients may present a unique challenge to anesthesia clinicians in airway management. Videolaryngoscopes may provide better airway visualization, which theoretically improves intubation success. However, previous work in morbidly obese patients was limited. We therefore tested the primary hypothesis that the use of McGrath video laryngoscope improves visualization of the vocal cords versus Macintosh direct laryngoscopy (Teleflex, Morrisville, NC) in morbidly obese patients.

METHODS

We enrolled 130 surgical patients, aged 18-99 years, with a body mass index ≥40 kg/m and American Society of Anaesthesiologists (ASA) physical status I-III. Patients were randomly allocated 1:1-stratified for patient's body mass index ≥50 kg/m-to McGrath video laryngoscope versus direct laryngoscopy with a Macintosh blade. The study groups were compared on glottis visualization, defined as improved Cormack and Lehane classification, with proportional odds logistic regression model.

RESULTS

McGrath video laryngoscope provided significantly better glottis visualization than Macintosh direct laryngoscopy with an estimated odds ratio of 4.6 (95% confidence interval [CI], 2.2-9.8; P < .01). We did not observe any evidence that number of intubation attempts and failed intubations increased or decreased.

CONCLUSIONS

McGrath video laryngoscope improves glottis visualization versus Macintosh direct laryngoscopy in morbidly obese patients. Large clinical trials are needed to determine whether improved airway visualization with videolaryngoscopy reduces intubation attempts and failures.

Novel airway device Vie Scope in several pediatric airway scenario: A randomized simulation pilot trial

CONTEXT

Endotracheal intubation of pediatric patients is challenging, especially in the pre-hospital emergency setting and if performed by less experienced providers. Securing an airway should be achieved with a single intubation attempt, as each intubation attempt contributes to morbidity and mortality. A new airway device, the VieScope, was recently introduced into clinical market, but efficacy to reduced intubation attempts remains unclear thus far.

OBJECTIVE

We aimed to compare endotracheal intubation by paramedics using the Vie Scope in different pediatric airway simulation conditions.

METHODS

We conducted a randomized, cross-over simulation study. Following a theoretical and practical training session, paramedics performed endotracheal intubation in 3 different pediatric emergency scenarios: normal airway; tongue edema; cardiopulmonary resuscitation using the VieScope. Overall intubation success rate was the primary outcome. Secondary outcomes included number of intubation attempts, time to intubation, Cormack-Lehane grade, POGO score, and ease of use (using 1-100 scale).

RESULTS

Fifty-five paramedics with at least 2 years of clinical experience and without any previous experience with the VieScope participated in this study. The overall intubation success rate was 100% in all 3 scenarios. The median intubation time was 27 (24-34) versus 27 (25-37) versus 29 (25-40) s for scenarios A, B, and C, respectively. In scenario A, all paramedics performed successful intubation with 1 single intubation attempt, whereas 2% of the paramedics had to perform 2 intubation attempts in scenario B and 9% in scenario C.

CONCLUSIONS

Results of this simulation study indicate preliminary evidence, that the VieScope enables adequate endotracheal intubation in the pediatric setting. Further clinical studies are needed to confirm these results.

Comparison of the new flexible tip bougie catheter and standard bougie stylet for tracheal intubation by anesthesiologists in different difficult airway scenarios: a randomized crossover trial

Background

Incidence of difficult endotracheal intubation ranges between 3 and 10%. Bougies have been recommended as an airway adjunct for difficult intubation, but reported success rates are variable. A new generation flexible tip bougie appears promising but was not investigated so far. We therefore compared the new flexible tip with a standard bougie in simulated normal and difficult airway scenarios, and used by experienced anesthesiologists.

Methods

We conducted a observational, randomized, cross-over simulation study. Following standardized training, experienced anesthesiologists performed endotracheal intubation using a Macintosh blade and one of the bougies in six different airway scenarios in a randomized sequence: normal airway, tongue edema, pharyngeal obstruction, manual cervical inline stabilization, cervical collar stabilization, cervical collar stabilization and pharyngeal obstruction. Overall success rate with a maximum of 3 intubation attempts was the primary endpoint. Secondary endpoints included number of intubation attempts, time to intubation and dental compression.

Results

Thirty-two anesthesiologist participated in this study between January 2019 and May 2019. Overall success rate was similar for the flexible tip bougie and the standard bougie. The flexible tip bougie tended to need less intubation attempts in more difficult airway scenarios. Time to intubation was less if using the flexible tip bougie compared to the standard bougie. Reduced severity of dental compression was noted for the flexible tip bougie in difficult airway scenarios except cervical collar stabilization.

Conclusion

In this simulation study of normal and difficult airways scenarios, overall success rate was similar for the flexible tip and standard bougie. Especially in more difficult airway scenarios, less intubation attempts, and less optimization maneuvers were needed if using the flexible tip bougie.

Trial registration

clinicaltrials.gov Identifier: NCT03733158. 7th November 2018.

Comparison of Direct and Video Laryngoscopes during Different Airway Scenarios Performed by Experienced Paramedics: A Randomized Cross-Over Manikin Study

Introduction. Airway management plays an essential role in anaesthesia practice, during both elective and urgent surgery procedures and emergency medicine.

Comparison of blind intubation via supraglottic airway devices versus standard intubation during different airway emergency scenarios in inexperienced hand: Randomized, crossover manikin trial

BACKGROUND

Securing the airway and enabling adequate oxygenation and ventilation is essential during cardiopulmonary resuscitation (CPR). The aim of the study was to evaluate the success rate of blind intubation via the I-Gel and the Air-Q compared with direct laryngoscopy guided endotracheal intubation by inexperienced physician and to measure time to successful intubation.

METHODS

The study was designed as a randomized, cross-over simulation study. A total of 134 physicians, from specialties other than Anesthesia or Emergency Medicine, who considered themselves skilled in endotracheal intubation but who have never used any kind of supraglottic airway device performed blind intubation via the I-Gel and Air-Q and direct laryngoscopy guided endotracheal intubation in 3 randomized scenarios: normal airway without chest compression during intubation attempt; normal airway with continuous chest compression during intubation attempt; difficult airway with continuous chest compression.

RESULTS

Scenario A: Success rate with initial intubation attempt was 72% for endotracheal intubation, 75% in Air-Q, and 81% in I-Gel. Time to endotracheal intubation and ease of intubation was comparable with all 3 airway devices used. Scenario B: Success rate with the initial intubation attempt was 42% for endotracheal intubation, compared with 75% in Air-Q and 80% in I-Gel. Time for endotracheal intubation was significantly prolonged in endotracheal intubation (42 seconds, 35-49), compared with Air-Q (21 seconds, 18-32) and I-Gel (19 seconds, 17-27). Scenario C: The success rate with the initial intubation attempt was 23% in endotracheal intubation, compared with 65% in Air-Q and 74% in I-Gel. Time to intubation was comparable with both supraglottic airway devices (20 vs 22 seconds) but was significantly shorter compared with endotracheal intubation (50 seconds, P < .001).

CONCLUSIONS

Less to moderately experienced providers are able to perform endotracheal intubation in easy airways but fail during ongoing chest compressions and simulated difficult airway. Consequently, less to moderately experienced providers should refrain from endotracheal intubation during ongoing chest compressions during CPR and in expected difficult airways. Supraglottic airway devices are reliable alternatives and blind intubation through these devices is a valuable airway management strategy.

Thyromental height test as a new method for prediction of difficult intubation with double lumen tube

Background

Predicting difficult intubation is of high clinical interest.

Methods

237 patients aged ≥18 years were included in the study. Preoperative airway evaluation included: Mallampati test, thyromental distance, sternomental distance and thyromental height test. During direct laryngoscopy Cormack & Lehane classification was graded. We calculated the ROC AUC, sensitivity and specificity for thyromental height test as a primary end point of our study.

Results

Only thyromental height test and Cormack-Lehane scale proved significant on occurrence of difficult intubation. The optimal sensitivity and specificity values of thyromental height test were met with a cut off value of 50 mm. With 1 mm increase in thyromental height test, risk of difficult intubation decreased by 7%.

Conclusion

Thyromental height test is a simple, easy to perform and non-invasive test to predict difficult intubation in patients scheduled for elective double lumen tube intubation during thoracic surgical procedures. With 1 mm above 50 mm increase in thyromental height test the risk of difficult intubation decreased by 7%.

Trial registration

Clinicaltrials.gov Identifier: NCT02988336.

Degree of obesity is not associated with more than one intubation attempt: a large centre experience

BACKGROUND

The role of obesity as a risk factor for difficult intubation remains controversial. We primarily assessed the association between body mass index (BMI) and difficult tracheal intubation.

METHODS

We analysed electronic records of more than 67 000 adults having elective non-cardiac surgery requiring tracheal intubation at the Cleveland Clinic between 2011 and 2015. The association between BMI and difficult intubation, defined as more than one intubation attempt, was assessed using multivariable logistic regression adjusting for pre-specified confounders.

RESULTS

Amongst 40 183 patients with BMI <30 kg m^-2 and 27 519 with BMI ≥30 kg m^-2, 9% required more than one intubation attempt. Increasing BMI up to 30 kg m^-2 was significantly associated with increased odds of more than one intubation attempt [odds ratio (OR): 1.03; 97.5% confidence interval (CI): 1.02, 1.04] per unit increase in BMI, P < 0.001. However, the odds of difficult intubation remained unchanged once BMI exceeded 30 kg m^-2 (P = 0.08). The results were similar when analysis was restricted to patients without history of airway abnormalities in whom intubation was attempted using a standard direct laryngoscope (OR: 1.03; 99.4% CI: 1.01, 1.04) per kg m^-2 increase in BMI <30 kg m^-2).

CONCLUSIONS

Increasing BMI was associated with increasing odds of difficult intubation in the lean range. At higher BMI, the odds of difficult intubation remain elevated, but there is no additional increase in odds with further increase in BMI. Obese patients were thus harder to intubate than lean ones, but difficult intubation was no more likely in morbidly obese patients than in those who were only slightly obese.