AIRWAY MANAGEMENT (GENERAL)

The evolution of airway management - new concepts and conflicts with traditional practice.

McNarry AF, Patel A

Br J Anaesth. 2017 Dec 1;119(suppl_1):i154-i166

ABSTRACT:In the last 25 yr, there have been several advances in the safe management of the airway. Videolaryngoscopes and supraglottic airways, now in routine use by new trainees in anaesthesia, have had their genesis in the recent past. The 4th National Audit Project of the Royal College of Anaesthetists and the Difficult Airway Society published in 2011 a seminal report that has influenced airway management worldwide. Understanding how the report's recommendations were constructed and how clinical guidelines compliment rather than contradict them is important in understanding the tenets of safe airway management. Over the last 25 yr there has been an increasing understanding of the effects of human factors in anaesthesiology: we may not perform in a predictable or optimal manner when faced with unusual and threatening challenges. The place of cricoid pressure in anaesthetic practice has also evolved. Current recommendations are that it be applied, but it should be released rapidly should airway difficulty be encountered. The need to prevent hypoxaemia by preoxygenation has long been recognized, but the role of high-flow nasal oxygen in anaesthesia is now being realized and developed. Clinicians must decide how novel therapies and long-standing practices are adapted to best meet the needs of our patients and prevent harm during airway management.

Association of prehospital intubation with decreased survival among pediatric trauma patients in Iraq and Afghanistan.

Schauer SG, Naylor JF, Hill GJ, Arana AA, Roper JL, April MD

Am J Emerg Med. 2017 Dec 1. pii: S0735-6757(17)30981-6

 

INTRODUCTION: Airway compromise is the second leading cause of preventable death on the battlefield among US military casualties. Airway management is an important component of pediatric trauma care. Yet, intubation is a challenging skill with which many prehospital providers have limited pediatric experience. We compare mortality among pediatric trauma patients undergoing intubation in the prehospital setting versus a fixed-facility emergency department.

METHODS: We queried the Department of Defense Trauma Registry (DODTR) for all pediatric encounters in Iraq and Afghanistan from January 2007 to January 2016. We compared outcomes of pediatric subjects undergoing intubation in the prehospital setting versus the emergency department (ED) setting.

RESULTS: During this period, there were 3439 pediatric encounters (8.0% of DODTR encounters during this time). Of those, 802 (23.3%) underwent intubation (prehospital=211, ED=591). Compared to patients undergoing ED intubation, patients undergoing prehospital intubation had higher median composite injury severity scores (17 versus 16) and lower survival rates (66.8% versus 79.9%, p<0.001). On univariable logistic regression analysis, prehospital intubation increased mortality odds (OR 1.97, 95% CI 1.39-2.79). After adjusting for confounders, the association between prehospital intubation and death remained significant (OR 2.03, 95% CI 1.35-3.06).

CONCLUSIONS: Pediatric trauma subjects intubated in the prehospital setting had worse outcomes than those intubated in the ED. This finding persisted after controlling for measurable confounders.

Management of right main bronchial rupture with a double lumen endotracheal tube in a patient with blunt chest trauma.

Seol SH, Lee WJ, Woo SH, Kim DH, Suh JH

Clin Exp Emerg Med. 2017 Dec 30;4(4):250-253

 

Tracheobronchial disruption is one of the most severe injuries caused by blunt chest trauma. It may cause airway obstruction and resulting life-threatening respiratory deficiency. However, the clinical presentations are variable and frequently difficult to diagnose. We report a case of a previously healthy 16-year-old man with complete right main bronchial transection sustained after a vehicular accident, who had progressive dyspnea, subcutaneous emphysema in the neck and anterior chest wall, and bilateral tension pneumothorax. Prompt chest tube drainage for suspected bilateral tension pneumothorax and a tracheal intubation were performed. Shortly after the positive pressure ventilation, severe subcutaneous emphysema developed and he was at risk for developing shock. Additional chest tubes were inserted. An emergency bronchoscopy showed rupture of the right main bronchus. After changing to a double lumen endotracheal tube, the patient's condition improved. A surgical closure was performed and postoperative bronchoscopy showed good repair. The patient was discharged without complications.

EXTRAGLOTTIC AIRWAYS

A randomised controlled trial comparing ProSeal laryngeal mask airway, i-gel and Laryngeal Tube Suction-D under general anaesthesia for elective surgical patients requiring controlled ventilation.

Das B, Varshney R, Mitra S

Indian J Anaesth. 2017 Dec;61(12):972-977.

Background and Aims: The ProSeal™ laryngeal mask airway (PLMA), i-gel™ and Laryngeal Tube Suction-D (LTS-D™) have previously been evaluated alone or in pair-wise comparisons but differing study designs make it difficult to compare the results. The aim of this study was to compare the clinical performance of these three devices in terms of efficacy and safety in patients receiving mechanical ventilation during elective surgical procedures.Methods: This prospective, randomised, double-blind study was conducted on 150 American Society of Anesthesiologists physical status I-II patients, randomly allocated into 3 groups, undergoing elective surgical procedures under general anaesthesia. PLMA, i-gel™ or LTS-D™ appropriate for weight or/and height was inserted. Primary outcome measured was airway sealing pressure. Insertion time, ease of insertion, number of attempts, overall success rate and the incidence of airway trauma and complications were also recorded. Intergroup differences were compared using one-way analysis of variance with post hoc correction for continuous data and Chi-square test for categorical variables.Results: Overall success rate was comparable between the three devices (i-gel™ 100%, LTS-D™ 94%, PLMA 96%). Airway sealing pressure was lower with i-gel™ (23.38 ± 2.06 cm H2O) compared to LTS-D™ (26.06 ± 2.11 cm H2O) and PLMA (28.5 ± 2.8 cm H2O; P < 0.0005). The mean insertion time was significantly more in PLMA (38.77 ± 3.2 s) compared to i-gel™ (27.9 ± 2.53 s) and LTS-D™ (21.66 ± 2.31 s; P < 0.0005).Conclusion: Airway sealing pressure and insertion time were significantly higher in PLMA compared to i-gel™ and LTS-D™.

Clinical Comparison of I-Gel Supraglottic Airway Device and Cuffed Endotracheal Tube for Pressure-Controlled Ventilation During Routine Surgical Procedures.

Dhanda A, Singh S, Bhalotra AR, Chavali S

Turk J Anaesthesiol Reanim. 2017 Oct;45(5):270-276

Objective: Recently, there has been a trend favouring the use of supraglottic airway devices over endotracheal tubes (ETT) during short surgical procedures. In this study, we are going to assess the suitability of one such supraglottic airway device, i-gel, for pressure-controlled ventilation (PCV) during routine surgical procedures.

Methods: The airway management for 60 patients was done with either i-gel (Group I) or cuffed tracheal tube (Group E) for this prospective, randomised, double-blinded study. Insertion time, number of attempts, ease of insertion and haemodynamic monitoring were recorded before, during and after insertion of these devices. Airway leak tests, leak volume and leak fraction were measured at 15, 20 and 25 cm H2O PCV, and pharyngolaryngeal morbidity was evaluated postoperatively.

Results: I-gel is easier to insert than a tracheal tube (p=0.0056). The increase in heart rate and MAP was higher following insertion of tracheal tube in the first few minutes (p<0.001) and subsequently became comparable between the two groups. The leak volume and leak fraction between the two groups were comparable at 15 cm H2O PCV, but significant difference was seen at 20 and 25 H2O PCV between the two groups (p=0.232, p<0.001, p<0.001). Thirty minutes later, the leak volume and leak fraction between groups were comparable at 15 cm H2O PCV (p=0.495, p=0.104) but not at 20 and 25 H2O PCV (p<0.001, p<0.001). Pharyngolaryngeal morbidity was significantly lesser in the i-gel group.

Conclusion: I-gel provides a reasonable alternative to cuffed ETT for pressure-controlled ventilation provided the pressures can be limited to 15 to 20 cm H2O.

Advantages, Disadvantages, Indications, Contraindications and Surgical Technique of Laryngeal Airway Mask.

Jannu A, Shekar A, Balakrishna R, Sudarshan H, Veena GC, Bhuvaneshwari S

Arch Craniofac Surg. 2017 Dec;18(4):223-229

ABSTRACT:The beauty of the laryngeal mask is that it forms an air tight seal enclosing the larynx rather than plugging the pharynx, and avoid airway obstruction in the oropharynx. The goal of its development was to create an intermediate form of airway management face mask and endotracheal tube. Indication for its use includes any procedure that would normally involve the use of a face mask. The laryngeal mask airway was designed as a new concept in airway management and has been gaining a firm position in anesthetic practice. Despite wide spread use the definitive role of the laryngeal mask airway is yet to be established. In some situations, such as after failed tracheal intubation or in oral surgery its use is controversial. There are several unresolved issues, for example the effect of the laryngeal mask on regurgitation and whether or not cricoids pressure prevents placement of mask. We review the techniques of insertion, details of misplacement, and complications associated with use of the laryngeal mask. We then attempt to clarify the role of laryngeal mask in air way management during anesthesia, discussing the advantages and disadvantages as well as indications and contraindications of its use in oral and maxillofacial surgery.

Comparison Of The I-Gel Supraglottic And King Laryngotracheal Airways In A Simulated Tactical Environment.

March JA, Tassey TE, Resurreccion NB, Portela RC, Taylor SE.

Prehosp Emerg Care. 2018 Jan 24:1-5

BACKGROUND: When working in a tactical environment there are several different airway management options that exist. One published manuscript suggests that when compared to endotracheal intubation, the King LT laryngotracheal airway (KA) device minimizes time to successful tube placement and minimizes exposure in a tactical environment. However, comparison of two different blind insertion supraglottic airway devices in a tactical environment has not been performed. This study compared the I-Gel airway (IGA) to the KA in a simulated tactical environment, to determine if one device is superior in minimizing exposure and minimizing time to successful tube placement.

METHODS: This prospective randomized cross over trial was performed using the same methods and tactical environment employed in a previously published study, which compared endotracheal intubation versus the KA in a tactical environment. The tactical environment was simulated with a one-foot vertical barrier. The participants were paramedic students who wore an Advanced Combat Helmet (ACH) and a ballistic vest (IIIA) during the study. Participants were then randomized to perform tactical airway management on an airway manikin with either the KA or the IGA, and then again using the alternate device. The participants performed a low military type crawl and remained in this low position during each tube placement. We evaluated the time to successful tube placement between the IGA and KA. During attempts, participants were videotaped to monitor their height exposure above the barrier. Following completion, participants were asked which airway device they preferred. Data was analyzed using Student's t-test across the groups for time to ventilation and height of exposure.

RESULTS: In total 19 paramedic students who were already at the basic EMT level participated. Time to successful placement for the KA was 39.7 seconds (95%CI: 32.7-46.7) versus 14.4 seconds (95%CI: 12.0-16.9) for the IGA, p < 0.001. Maximum height exposure of the helmet above a one foot vertical barrier for the KA resulted in 1.42 inches of exposure (95%CI: 0.38-0.63) compared to the IGA with 1.42 inches, 95%CI:0.32-0.74, p = 0.99. On questioning 100% of the participants preferred the IGA device over the KA.

CONCLUSION: In a simulated tactical environment placement of the IGA for airway management was faster than with the KA, but there was no difference in regard to exposure. Additionally, all the participants preferred using the IGA device over the KA.

Extraglottic Airways in Tactical Combat Casualty Care: TCCC Guidelines Change 17-01 28 August 2017.

Otten EJ, Montgomery HR, Butler FK Jr.

J Spec Oper Med. Winter 2017;17(4):19-28.

ABSTRACT:Extraglottic airway (EGA) devices have been used by both physicians and prehospital providers for several decades. The original TCCC Guidelines published in 1996 included a recommendation to use the laryngeal mask airway (LMA) as an option to assist in securing the airway in Tactical Evacuation (TACEVAC) phase of care. Since then, a variety of EGAs have been used in both combat casualty care and civilian trauma care. In 2012, the Committee on TCCC (CoTCCC) and the Defense Health Board (DHB) reaffirmed support for the use of supraglottic airway (SGA) devices in the TACEVAC phase of TCCC, but did not recommend a specific SGA based on the evidence available at that point in time. This paper will use the more inclusive term "extraglottic airway" instead of the term "supragottic airway" used in the DHB memo. Current evidence suggests that the i-gel® (Intersurgical Complete Respiratory Systems; http://www.intersurgical.com/info/igel) EGA performs as well or better than the other EGAs available and has other advantages in ease of training, size and weight, cost, safety, and simplicity of use. The gel-filled cuff in the i-gel both eliminates the need for cuff pressure monitoring during flight and reduces the risk of pressure-induced neuropraxia to cranial nerves in the oropharynx and hypopharynx as a complication of EGA use. The i-gel thus makes the medic's tasks simpler and frees him or her from the requirement to carry a cuff manometer as part of the medical kit. This latest change to the TCCC Guidelines as described below does the following things: (1) adds extraglottic airways (EGAs) as an option for airway management in Tactical Field Care; (2) recommends the i-gel as the preferred EGA in TCCC because its gel-filled cuff makes it simpler to use than EGAs with air-filled cuffs and also eliminates the need for monitoring of cuff pressure; (3) notes that should an EGA with an air-filled cuff be used, the pressure in the cuff must be monitored, especially during and after changes in altitude during casualty transport; (4) emphasizes COL Bob Mabry's often-made point that extraglottic airways will not be tolerated by a casualty unless he or she is deeply unconscious and notes that an NPA is a better option if there is doubt about whether or not the casualty will tolerate an EGA; (5) adds the use of suction as an adjunct to airway management when available and appropriate (i.e., when needed to remove blood and vomitus); (6) clarifies the wording regarding cervical spine stabilization to emphasize that it is not needed for casualties who have sustained only penetrating trauma (without blunt force trauma); (7) reinforces that surgical cricothyroidotomies should not be performed simply because a casualty is unconscious; (8) provides a reminder that, for casualties with facial trauma or facial burns with suspected inhalation injury, neither NPAs nor EGAs may be adequate for airway management, and a surgical cricothyroidotomy may be required; (9) adds that pulse oximetry monitoring is a useful adjunct to assess airway patency and that capnography should also be used in the TACEVAC phase of care; and (10) reinforces that a casualty's airway status may change over time and that he or she should be frequently reassessed.

ProSeal Laryngeal Mask Airway versus Cuffed Endotracheal Tube for Laparoscopic Surgical Procedures under General Anesthesia: A Random Comparative Study.

Parikh SS, Parekh SB, Doshi C, Vyas V

Anesth Essays Res. 2017 Oct-Dec;11(4):958-963

Context: The Proseal LMA(PLMA), which has been designed especially for positive pressure ventilation and protection against aspiration can act as an alternative to Endotracheal Tube (ETT) as an effective airway device for patients undergoing elective Laparoscopic surgeries.

Aims: To compare the efficacy and safety of PLMA with ETT in patients undergoing Laparoscopic surgeries under general anaesthesia.Settings and Design: A prospective, randomized study was conducted in a tertiary care teaching hospital with 60 patients of ASA grade I/II undergoing elective Laparoscopic surgery under general anaesthesia. Ethical committee clearance and written consent taken. The patients were randomly divided into two equal groups to the PLMA group (Group S) and to the ETT group (Group C) Heart rate (HR), mean blood pressure (MAP), ETCO2 values, intraoperative complications such as regurgitation- aspiration, and Postoperative complications such as nausea or vomiting, throat soreness and oral injuries were monitored.

Results: There was no difference demographically. Insertion success rate was 100% for both the groups. The mean increase in HR was seen all throughout the duration of the surgery to 8 % above the baseline in Group C and to 3% above the baseline in Group S. On comparing the MAP in Group C, there was a increased by 2.5% to 78.300 ± 14.2615 mmHg as compared to an increase by 5% to 76.233 ± 6.2072 mmHg in Group S. EtCO2 showed a rise in both groups after pneumoperitoneum, which returned to baseline values after completion of surgery. Gastric aspirate values showed no difference in each group. Post op complications were seen mainly inGroup C with statistical significance.

Conclusions: A properly positioned PLMA is a suitable and safe alternative to ETT for airway management in adequately fasted, adult patients undergoing elective Laparoscopic surgeries.

Emergency insertion of the LMA protector airway in patients in the lateral position.

Ueshima H, Otake H

J Clin Anesth. 2018 Feb;44:116

 

No Abstract on PubMed

Highlights:

•The LMAR Protector™ Airway is a new type of second generation airway.

•Protector has an integrated cuff pressure indicator.

•Protector is effective for an emergency insertion in the lateral position.

CRICOTHYROIDOTOMY

Cricothyroid Membrane Puncture-Guided Tracheostomy: A New Technique for Emergency Airway Access.

Chen Y, Han Y, August M, Ferraro NF, Zhang Q, Zhang H

J Oral Maxillofac Surg. 2018 Jan 9. pii: S0278-2391(18)30005-3. doi: 10.1016/j.joms.2017.12.028.

PURPOSE: We sought to compare cricothyroid membrane puncture-guided tracheostomy (CMPGT) with surgical cricothyroidotomy (SC) and percutaneous tracheostomy with Griggs' guidewire dilating forceps (GWDF) for establishing an emergency airway in a porcine model. We hypothesized that CMPGT would be associated with a shorter time to ventilation and more rapid restoration of oxygenation.

MATERIALS AND METHODS: We implemented a small pilot animal study. Eighteen miniature pigs were randomly assigned to undergo CMPGT, SC, or GWDF. The predictor variable was the technique used. The primary outcome variable was time to ventilation. Other outcome variables were efficiency of oxygenation restoration, procedure duration, and procedure-related complications. The data were assessed using 1-way analysis of variance and Bonferroni correction. The oxygen saturation (SpO2) changes over time were graphed using a time-series line plot. Statistical significance was set at P < .05.

RESULTS: Airways were successfully established in all 18 pigs. SC (68 ± 4 seconds) showed the shortest procedure duration compared with GWDF (95 ± 3 seconds) and CMPGT (96 ± 4 seconds); however, the time to ventilation using CMPGT (21 ± 2 seconds) was significantly shorter than that with SC (68 ± 4 seconds) and GWDF (95 ± 3 seconds) (P < .01). Spo2 in each group increased postoperatively, reaching 95% at 120 seconds, 131 seconds, and144 seconds in the CMPGT, SC, and GWDF groups, respectively. The slope of the ascending phase of the Spo2 curve was 0.38 for CMPGT, 0.42 for SC, and 0.53 for GWDF (P < .05). Two pigs in each group had minor intraoperative bleeding, and 1 pig in the SC group had moderate bleeding.

CONCLUSIONS: The results of this animal study suggest that CMPGT is a time-efficient and safe technique for emergency airway access that allows for a more rapid return of ventilation and obviates conversion to definitive tracheostomy. Further cadaveric study is ongoing.

A randomized cross-over study comparing surgical cricothyrotomy techniques by combat medics using a synthetic cadaver model.

Schauer SG, D Fernandez JR, L Roper J, Brown D, L Jeffers K, Srichandra J, Davids NB, April MD

Am J Emerg Med. 2017 Nov 27. pii: S0735-6757(17)30972-5. doi: 10.1016/j.ajem.2017.11.062.

 

OBJECTIVE: Cricothyrotomy is a complex procedure with a high rate of complications including failure to cannulate and injury to adjacent anatomy. The Control-Cric™ System and QuickTrach II™ represent two novel devices designed to optimize success and minimize complications with this procedure. This study compares these two devices against a standard open surgical technique.

METHODS: We conducted a randomized crossover study of United States Army combat medics using a synthetic cadaver model. Participants performed a surgical cricothyrotomy using the standard open surgical technique, Control-Cric™ System, and QuickTrach II™ device in a random order. The primary outcome was time to successful cannulation. The secondary outcome was first-attempt success. We also surveyed participants after performing the procedures as to their preferences.

RESULTS: Of 70 enrolled subjects, 65 completed all study procedures. Of those that successfully cannulated, the mean times to cannulation were comparable for all three methods: standard 51.0s (95% CI 45.2-56.8), QuickTrach II™ 39.8s (95% CI 31.4-48.2) and the Cric-Control™ 53.6 (95% CI 45.7-61.4). Cannulation failure rates were not significantly different: standard 6.2%, QuickTrach II™ 13.9%, Cric-Control™ 18.5% (p=0.106). First pass success rates were also similar (93.4%, 91.1%, 88.7%, respectively, p=0.670). Of respondents completing the post-study survey, a majority (52.3%) preferred the QuickTrach II™ device.

CONCLUSIONS: We identified no significant differences between the three cricothyrotomy techniques with regards to time to successful cannulation or first-pass success.

Predictors of arterial desaturation during intubation: a nested case-control study of airway management-part I.

Smischney NJ, Seisa MO, Heise KJ, Wiegand RA, Busack KD, Loftsgard TO, Schroeder DR, Diedrich DA

J Thorac Dis. 2017 Oct;9(10):3996-4005

 

Background: Arterial desaturations experienced during endotracheal intubation (ETI) may lead to poor outcomes. Thus, our primary aim was to identify predictors of arterial desaturation (pulse oximetry <90%) during the peri-intubation period and to assess outcomes of those who developed arterial hypoxemia.

Methods: Adult patients admitted to a medical and/or surgical intensive care unit (ICU) over the time period of January 1st 2013 through December 31st 2014 who required ETI were included. Only the first intubation was captured. Arterial desaturation was defined as pulse oximetry readings of <90% (hypoxemia) in the immediate peri-intubation period. Patients were then grouped in cases (those who developed desaturation) and controls (those who did not develop this complication).

Results: The final cohort included 420 patients. Arterial desaturations occurred in 74 (18%) patients. When adjusting for significant predictors on univariate analysis and known predictors of a difficult airway, only acute respiratory failure (OR 2.38; 95% CI: 1.15-4.93; P=0.02) and provider training level (OR 7.12; 95% CI: 1.65-30.67; P=0.016) remained significant. Higher pulse oximetry readings prior to intubation was found to be protective on multivariate analysis (OR 0.92; 95% CI: 0.89-0.96; P<0.01; per one percent increase).

Conclusions: Patients who were intubated for acute respiratory failure and those who were intubated by junior level trainees had increased odds of experiencing arterial desaturation in the peri-intubation period. Patients experiencing arterial desaturation had lower pulse oximetry readings prior to intubation suggesting a possible delay at intubation.