Conventional Versus Video Laryngoscopy for Tracheal Tube Exchange. Glottic Visualization, Success Rates, Complications, and Rescue Alternatives in the High Risk Difficult Airway Patient.

Tom Mort has focussed on the advanced technique of using Video Laryngoscopy to monitor the high risk activity of exchange catheter use. The video images allow timely rotation or manipulation of the Tube and AEC to assure completion of the procedure.

Mort, Thomas C. MD , Braffett , Barbara H. PhD.
Hartford Hospital , Hartford Connecticut.

    Building on previous work showing the increased level of complications associated with multiple attempts at intubation and demonstration that video laryngoscopy could be used effectively in conjunction with an exchange catheter ( AEC ) for endotracheal tube exchange, this work consolidates earlier ideas. (1-2).

Abstract:

BACKGROUND: Tracheal tube exchange is a simple concept but not a simple procedure because hypoxemia, esophageal intubation, and loss of airway may occur with life-threatening ramifications. Combining laryngoscopy with an airway exchange catheter (AEC) may lessen the exchange risk. Laryngoscopy is useful for a pre-exchange examination and to open a pathway for endotracheal tube (ETT) passage. Direct laryngoscopy (DL) is hampered by a restricted "line of sight"; thus, airway assessment and exchange may proceed blindly and contribute to difficulty and complications. We hypothesized that video laryngoscopy (VL), when compared with DL, will improve glottic viewing for airway assessment, and the VL-AEC method of ETT exchange will result in a reduction in airway and hemodynamic complications in high-risk patients when compared with a historical group of patients who underwent DL + AEC-assisted exchange.

METHODS: Critically ill patients requiring an ETT exchange underwent DL-assisted pre-exchange airway assessment. If the DL-assisted pre-exchange assessment rendered a "poor view," these patients underwent a VL-based airway assessment followed by a VL-assisted ETT exchange procedure. The DL and VL pre-exchange assessments were compared. The attempts, complications, and rescue devices required for ETT exchange were analyzed. These exchange results were then compared with a historical control group of patients who (1) were classified as a poor view on DL-assisted pre-exchange airway assessment; and (2) underwent a DL + AEC-assisted exchange. The airway assessment and ETT exchange were performed by a board-certified anesthesiologist from the Department of Anesthesiology alone or with anesthesia resident assistance.

RESULTS: Three hundred twenty-eight patients with a poor view on initial DL examination underwent a subsequent VL with comparison of views with the 337 patients in the historical control group (DL + AEC). A majority (88%) had a "full or near-full view" on VL examination. The first-pass success rate for ETT exchange was greater in the VL group (91.5% vs 67.7% with DL; P = 0.0001) and the number of patients requiring 3+ attempts was lower (1.2% vs 6.8% with DL; P = 0.0003). A commensurate difference in the incidence of mild and severe hypoxemia, esophageal intubation, bradycardia, and the need for rescue airway device intervention was also observed with VL exchange procedures when compared with the historical DL + AEC group.

CONCLUSIONS: These findings support the hypothesis that VL may result in better glottic viewing for airway assessment and may permit the ETT exchange procedure to be performed with fewer airway and hemodynamic complications. Execution of the ETT exchange over an AEC was augmented by improved glottic visualization to allow more efficient and timely ETT passage. Multiple attempts to resecure the airway increased the number of exchange complications. VL + AEC exchange led to fewer attempts and is consistent with the recommendation of the American Society of Anesthesiologists Difficult Airway Task Force to limit laryngoscopic attempts and, as a consequence, decrease complications. A VL-based pre-exchange airway assessment may be a valuable procedure for both planning the exchange and uncovering unrecognized airway maladies, for example, partial or complete self-extubation.

References:

1.Emergency Tracheal Intubation: Complications Associated
with Repeated Laryngoscopic Attempts
Thomas C. Mort, MDDepartment of Anesthesiology, Hartford Hospital, University of Connecticut School of Medicine
Anesth Analg 2004;99:607–13

2.Tracheal tube exchange: feasibility of continuous glottic viewing with advanced laryngoscopy assistance.Mort TC. Anesth Analg. 2009 Apr;108(4):1228-31. doi: 10.1213/ane.0b013e3181990a82.

A randomized multi-institutional crossover comparison of the GlideScope® Cobalt Video laryngoscope to the flexible fiberoptic bronchoscope in a Pierre Robin manikin

1. Pediatric Anesthesia   
2. John E. Fiadjoe^1,*, 
3. Matthew Hirschfeld¹, 
4. Stephan Wu¹, 
5. James Markley¹, 
6. Harshad Gurnaney¹, 
7. Abbas F. Jawad¹, 
8. Paul Stricker¹, 
9. Todd Kilbaugh¹, 
10. Patrick Ross² and
11. Pete Kovatsis³

Article first published online: 27 APR 2015
DOI: 10.1111/pan.12668

The Manikin study reported by John Fiadjoe et. al. illustrates findings that possibly indicate ease of learning the device handling features of equipment rather than effectiveness of the VL and FOB devices in the Pierre Roban complex . The jump from Manikin to Actual patient care is significant and is affected by secretions, relaxation, and muscular tone. 

This study did show that an institutional difference in results was apparent suggesting the need for disciplined training to achieve optimal results. The people are being measured as well as the devices in question. This study comes from a very experienced group of paediatric airway managers.

Summary

Background

The GlideScope Cobalt Video laryngoscope is being used more often in children with challenging laryngoscopy. There are, however, no pediatric trials comparing it to flexible fiberoptic bronchoscopy, the current accepted gold standard. This preliminary manikin study compares the first-attempt intubation success of the GlideScope Cobalt video laryngoscope to the flexible fiberoptic bronchoscope when performed by attending pediatric anesthesiologists at two major pediatric centers.

Methods

This prospective randomized, crossover study evaluated 120 attempts (60 with each study device) to intubate the AirSim Pierre Robin manikin (PRM) with fiberoptic bronchoscopy and video laryngoscopy (VL). Attending pediatric anesthesiologists from two quaternary pediatric centers were eligible to participate. Each attending anesthesiologist randomly performed a single tracheal intubation attempt with one of the study devices followed by the alternate method. The primary outcome was the first-attempt success rate of tracheal intubation. Blinding was not feasible. We hypothesized that first-attempt success would be higher with fiberoptic bronchoscopy.

Results

Thirty anesthesiologists from each center were randomized to use one of the study devices followed by the alternate method. We analyzed all participants' data. There was no overall difference in first-attempt success between VL and fiberoptic bronchoscopy (88.3% vs 85% respectively, P = 0.59). There were significant institutional differences in first-attempt success using VL (76.7% vs 100%).

Conclusions

There was no difference in first-attempt success of tracheal intubation using VL vs fiberoptic bronchoscopy when performed by attending anesthesiologists at two large pediatric centers. However, institutional differences exist in success rates with VL across the two centers. Results from single-center device evaluations should be verified by multi-center evaluations. A significant proportion of attending anesthesiologists lack experience with advanced airway devices; targeted education may enhance intubation success and patient safety.

Tracheal intubation in patients with odentogenous abscesses and reduced mouth opening- REPEAT POST

British Journal of Anaesthesia 112 (2): 348–54 (2014)

M. Schumann1, I. Biesler1, A. Borgers1, R. Pfortner2, C. Mohr2 and H. Groeben1*
1 Department of Anaesthesiology, Critical Care Medicine and Pain Therapy and 2 Department of Oral and Cranio-Maxillofacial Surgery, Kliniken
Essen-Mitte, Henricistr. 92, Essen 45136, Germany.

* Corresponding author. E-mail: h.groeben@kliniken-essen-mitte.de

Background. Odentogenous abscesses with involvement of the facial or cervical spaces can be

life-threatening andoften have to be drained under general anaesthesia. Trismus andswelling

can make intubation with a Macintosh laryngoscope difficult or even impossible. However,
indirect laryngoscopy has been successful when conventional direct laryngoscopy has
failed. Therefore, we evaluated the efficacy of the Glidescope laryngoscope in patients with
odentogenous abscesses and the improvement in mouth opening after neuromuscular block.
Methods. After approval of the ethics committee, 100 patients with odentogenous abscesses
were randomized to undergo tracheal intubation with the Glidescope or Macintosh
laryngoscope. Success rate, visualization of the glottis, intubation duration, and need for
supporting manoeuvres were evaluated.
Results. Intubation with the Glidescope was always successful, while conventional intubation
failed in 17 out of 50 patients (P,0.0001). In all patients in whom conventional tracheal
intubation failed, a subsequent attempt with the Glidescope was successful. The view at the
glottis (according to Cormack and Lehane; P,0.0001), intubation duration [34 s (CI 27–41)
vs 67 s (CI 52–82), mean (95% confidence interval); P.0.0001], and need for supporting
manoeuvres (P,0.0001) were significantly different. The inter-incisor distance improved
overall with induction of anaesthesia from 2.0 cm (CI 1.8–2.2) to 2.6 cm (CI 2.3–2.9;
P,0.0001) and was correlated with the duration of symptoms.
Conclusions. In patients with odentogenous abscesses, the use of a Glidescope laryngoscope
was associated with significantly faster tracheal intubation, with a better view, fewer
supporting manoeuvres, and a higher success rate than with a conventional laryngoscope.
Improvement of the inter-incisor distance after induction of anaesthesia correlated with
the duration of symptoms.
Keywords: intubation, difficult; intubation, tracheal; laryngoscope, Glidescope; laryngoscope,
Macintosh
Accepted for publication: 26 June 2013

Early clinical experience with a new videolaryngoscope (GlideScope) in 728 patients.

This landmark paper by Cooper Et. Al. was recognized as an important contribution to Airway understanding in Canada and the world. This was the first general use paper evaluating the GlideScope Video Laryngoscope.

Can J Anaesth. 2005 Feb;52(2):191-8.

Cooper RM1, Pacey JA, Bishop MJ, McCluskey SA.

Abstract

PURPOSE: 

To evaluate a new videolaryngoscope and assess its ability to provide laryngeal exposure and facilitate intubation.

METHODS: 

Five centres, involving 133 operators and a total of 728 consecutive patients, participated in the evaluation of a new video-laryngoscope [GlideScope (GS)]. Many operators had limited or no previous GS experience. We collected information about patient demographics and airway characteristics, Cormack-Lehane (C/L) views and the ease of intubation using the GS. Failure was defined as abandonment of the technique.

RESULTS: 

Data from six patients were incomplete and were excluded. Excellent (C/L 1) or good (C/L 2) laryngeal exposure was obtained in 92% and 7% of patients respectively. In all 133 patients in whom both GS and direct laryngoscopy (DL) were performed, GS resulted in a comparable or superior view. Among the 35 patients with C/L grade 3 or 4 views by DL, the view improved to a C/L 1 view in 24 and a C/L 2 view in three patients. Intubation with the GS was successful in 96.3% of patients. The majority of the failures occurred despite a good or excellent glottic view.

CONCLUSIONS: 

GS laryngoscopy consistently yielded a comparable or superior glottic view compared with DL despite the limited or lack of prior experience with the device. Successful intubation was generally achieved even when DL was predicted to be moderately or considerably difficult. GS was abandoned in 3.7% of patients. This may reflect the lack of a formal protocol defining failure, limited prior experience or difficulty manipulating the endotracheal tube while viewing a monitor.