Comparison of laryngeal mask and intubating laryngeal mask insertion by the naïve intubator

Ambu AuraGain versus intubating laryngeal tube suction as a conduit for endotracheal intubation

Background and Aims

Newly developed supraglottic airway devices (SGAs) are designed to be used both for ventilation and as conduits for endotracheal intubation with standard endotracheal tubes (ETTs). We compared the efficacy of the Ambu AuraGain (AAG) and the newly developed intubating laryngeal tube suction disposable (ILTS-D) as conduits for blind and fiber-optically guided endotracheal intubation in an airway mannequin.

Material and Methods

This is a prospective, randomized, crossover study in an airway mannequin, with two arms: blind ETT insertion by medical students and fiber-optically guided ETT insertion by anesthesiologists. The primary outcome variable was the time to achieve an effective airway through an ETT using AAG and ILTS-D as conduits. Secondary outcome variables were the time to achieve effective supraglottic ventilation and successful exchange with an ETT, and the success rates for blind endotracheal intubation and fiber-optically guided intubation techniques for both SGAs.

Results

Forty participants were recruited to each group. All participants were able to insert both devices successfully on the first attempt. For blind intubation, the success rate for establishing a definitive airway with an ETT using the SGA as a conduit was significantly higher with ILTS-D (82.5%) compared with AAG (20.0%) (P < 0.001). None of the participants were able to successfully complete the exchange of the SGA for the ETT with the AAG. In the fiber optic guided intubation group, the rate of successful exchange was significantly higher with ILTS-D (84.6%) compared with AAG (61.5%) (P = 0.041).

Conclusion

The ILTS-D successfully performs in an airway mannequin with higher success rate and shorter time for blindly establishing an airway with an ETT using the SGA as a conduit, compared with AAG. Further clinical trials are warranted.

Evaluation of the Intubating Laryngeal Mask Airway™ Used by Occasional Intubators in Simulated Trauma

This observational study assessed the potential role of the intubating laryngeal mask airway (ILMA™ ) for use by emergency care givers with limited laryngoscopy skills.

Six ambulance officers with advanced airway training, five doctors with intubation experience and five doctors without intubation experience were given a short instruction course on the use of the ILMA. They subsequently used the device on 80 consenting subjects anaesthetized for elective surgery after the application of cricoid pressure and manual in-line stabilization of the cervical spine. All patients were successfully ventilated via the ILMA. Mean (SD) times in seconds to ventilation were 27 (10), 33 (18) and 47 (22) respectively in the occasional intubator ambulance officers, occasional intubator doctor and naï ve intubator groups. The numbers (percentage) failures to intubate via the ILMA in each group were 2 (7%), 5 (20%) and 4 (16%) respectively. Mean (SD) times in seconds to intubation were 32 (23), 32 (17) and 36 (25). There was no evidence of “learning” with repeated use. The feedback forms were strongly supportive of a prehospital trial and also of having an ILMA available during all intubations. Participants almost universally rated the ILMA as easy to use. This study supports further evaluation of the ILMA in a large pre-hospital trial.

Suitability of a preserved human cadaver model for the simulation of facemask ventilation, direct laryngoscopy and tracheal intubation: a laboratory investigation

BACKGROUND

Using fresh or formalin-embalmed cadavers has not been generally accepted for the purposes of teaching airway management. We investigated whether cadavers 'preserved according Thiel's embalming method' (PATEM) are suitable for the simulation of facemask ventilation and tracheal intubation by direct laryngoscopy.

METHODS

This observational cluster sampling, controlled simulation study, included eight PATEM cadavers and eight manikins in two clusters. Twenty experienced anaesthetists were randomly assigned to execute 80 facemask ventilations and 80 tracheal intubations in both groups. The ease of facemask ventilation was the primary endpoint. The secondary endpoint was the composite outcomes of laryngoscopy and tracheal intubation.

RESULTS

The success rate at the first attempt at mask ventilation was 74% (59/80 attempts) on cadavers and 41% (33/80 attempts) on manikins (P<0.0001). Twenty one subjects received an oral airway in both groups and succeeded in facemask ventilation 20 times on cadavers and four times on manikins (P=0.004). Two-handed technique mask ventilation was required 24 times on manikins and once on cadavers (P=0.0016). In one attempt on a manikin the mask ventilation was impossible. Poor laryngeal view (Cormack-Lehane grade 3) occurred 14 times among cadavers (17.5%) and once in manikins (1.25%) (P=0.007), whereas difficulties in tracheal intubation were encountered 16 times in cadavers (20%) vs 17 times in manikins (21.25%) (P=0.84). In a subjective evaluation the participants preferred the cadaver model over the manikins (P<0.0001).

CONCLUSIONS

PATEM cadavers were better suited for facemask ventilation and provided a more realistic environment for laryngoscopy and tracheal intubation than the studied manikins.

Extraglottic airway devices: A review

Extraglottic airway devices (EAD) have become an integral part of anesthetic care since their introduction into clinical practice 25 years ago and have been used safely hundreds of millions of times, worldwide. They are an important first option for difficult ventilation during both in-hospital and out-of-hospital difficult airway management and can be utilized as a conduit for tracheal intubation either blindly or assisted by another technology (fiberoptic endoscopy, lightwand). Thus, the EAD may be the most versatile single airway technique in the airway management toolbox. However, despite their utility, knowledge regarding specific devices and the supporting data for their use is of paramount importance to patient's safety. In this review, number of commercially available EADs are discussed and the reported benefits and potential pitfalls are highlighted.

Intubating laryngeal mask airway placement by non-physician healthcare providers in management out-of-hospital cardiac arrests: a case series

AIM OF THE STUDY

The role of supralaryngeal devices in airway management in out-of-hospital cardiac arrests (OHCA) remains controversial. The aim of this prospective observational trial was to evaluate the feasibility and effectiveness of intubating laryngeal mask airway (ILMA) when used by trained prehospital emergency nurses in the setting of OHCA.

METHODS

After approval from the Research Ethics Board, prehospital emergency nurses trained in placement of ILMA (Fastrach™, LMA Vitaid, Toronto, Ontario, Canada) followed a formal protocol for airway control during OHCA. The primary outcome was the success rate of ILMA placement, while secondary outcomes were success rate of tracheal intubation through the ILMA, and the incidence of regurgitation of gastric contents.

RESULTS

During the study period, 302 ILMA placements were attempted by emergency nurses during OHCA resuscitation. After ILMA placement, but before attempt for intubation, ventilation was possible in 290 patients (96%). Obstruction or major leaks were observed in 12 patients (4%). Tracheal tube insertion through the ILMA was attempted in 265 patients, and was performed in 254 (95.8%). This allowed for proper lung ventilation through the tracheal tube in 242 cases whereas 12 tubes were esophageal or proved obstructed. Regurgitation of gastric contents occurred in 43 (14.2%) patients; in 23 cases before arrival of the first aid team, in 18 cases before ILMA placement, and in 2 cases after the ILMA placement.

CONCLUSION

The use of ILMA for airway management by trained emergency nurses during OHCA resuscitation is feasible and allows for effective airway management. The success rate of tracheal tube placement through the ILMA was high. In addition, the incidence of regurgitation was lower when using the ILMA than that previous historical reports with face-mask ventilation.

Laypersons can successfully place supraglottic airways with 3 minutes of training. A comparison of four different devices in the manikin

INTRODUCTION

Supraglottic airway devices have frequently been shown to facilitate airway management and are implemented in the ILCOR resuscitation algorithm. Limited data exists concerning laypersons without any medical or paramedical background. We hypothesized that even laymen would be able to operate supraglottic airway devices after a brief training session.

METHODS

Four different supraglottic airway devices: Laryngeal Mask Classic (LMA), Laryngeal Tube (LT), Intubating Laryngeal Mask (FT) and CobraPLA (Cobra) were tested in 141 volunteers recruited in a technical university cafeteria and in a shopping mall. All volunteers received a brief standardized training session. Primary endpoint was the time required to definitive insertion. In a short questionnaire applicants were asked to assess the devices and to answer some general questions about BLS.

RESULTS

The longest time to insertion was observed for Cobra (31.9 ± 27.9 s, range: 9-120, p < 0.0001; all means ± standard deviation). There was no significant difference between the insertion times of the other three devices. Fewest insertion attempts were needed for the FT (1.07 ± 0.26), followed by the LMA (1.23 ± 0.52, p > 0.05), the LT (1.36 ± 0.61, p < 0.05) and the Cobra (1.45 ± 0.7, p < 0.0001). Ventilation was achieved on the first attempt significantly more often with the FT (p < 0.001) compared to the other devices. Nearly 90% of the participants were in favor of implementing supraglottic airway devices in first aid algorithms and classes.

CONCLUSION

Laypersons are able to operate supraglottic airway devices in manikin with minimal instruction. Ventilation was achieved with all devices tested after a reasonable time and with a high success rate of > 95%. The use of supraglottic airway devices in first aid and BLS algorithms should be considered.

Insertion of six different supraglottic airway devices whilst wearing chemical, biological, radiation, nuclear-personal protective equipment: a manikin study

Six different supraglottic airway devices: Combitube™, laryngeal mask airway, intubating laryngeal mask airway (Fastrach™), i-gel™, Laryngeal Tube™ and Pro-Seal™ laryngeal mask airway were assessed by 58 paramedic students for speed and ease of insertion in a manikin, whilst wearing either chemical, biological, radiation, nuclear-personal protective equipment (CBRN-PPE) or a standard uniform. All devices took significantly longer to insert when wearing CBRN-PPE compared with standard uniform (p < 0.001). In standard uniform, insertion time was shorter than 45 s in 90% of attempts for all devices except the Combitube, for which 90% of attempts were completed by 53 s. Whilst wearing CBRN-PPE the i-gel was the fastest device to insert with a mean (SD (95% CI)) insertion time of 19 (8 (17-21))s, p < 0.001, with the Combitube the slowest with mean (65 (23 (59-71))s. Wearing of CBRN-PPE has a negative impact on supraglottic airway insertion time.

The effects of laryngeal mask airway passage simulation training on the acquisition of undergraduate clinical skills: a randomised controlled trial

BACKGROUND

Effective use of the laryngeal mask airway (LMA) requires learning proper insertion technique in normal patients undergoing routine surgical procedures. However, there is a move towards simulation training for learning practical clinical skills, such as LMA placement. The evidence linking different amounts of mannequin simulation training to the undergraduate clinical skill of LMA placement in real patients is limited. The purpose of this study was to compare the effectiveness in vivo of two LMA placement simulation courses of different durations.

METHODS

Medical students (n = 126) enrolled in a randomised controlled trial. Seventy-eight of these students completed the trial. The control group (n = 38) received brief mannequin training while the intervention group (n = 40) received additional more intensive mannequin training as part of which they repeated LMA insertion until they were proficient. The anaesthetists supervising LMA placements in real patients rated the participants' performance on assessment forms. Participants completed a self-assessment questionnaire.

RESULTS

Additional mannequin training was not associated with improved performance (37% of intervention participants received an overall placement rating of > 3/5 on their first patient compared to 48% of the control group, X2 = 0.81, p = 0.37). The agreement between the participants and their instructors in terms of LMA placement success rates was poor to fair. Participants reported that mannequins were poor at mimicking reality.

CONCLUSIONS

The results suggest that the value of extended mannequin simulation training in the case of LMA placement is limited. Educators considering simulation for the training of practical skills should reflect on the extent to which the in vitro simulation mimics the skill required and the degree of difficulty of the procedure.

Can emergency medical services personnel effectively place and use the Supraglottic Airway Laryngopharyngeal Tube (SALT) airway?

BACKGROUND

Various alternative airway devices have been developed in the last several years. Among these is the Supraglottic Airway Laryngopharyngeal Tube (SALT), which was designed to function as a basic mechanical airway and as an endotracheal tube (ET) introducer for blind endotracheal intubation (ETI).

OBJECTIVE

To determine the rate of successful placement of the SALT and the success rate of subsequent blind ET insertion by a cohort of emergency medical services (EMS) providers of varying levels of EMS certification.

METHODS

This study was a two-phase, two-group nonblinded, prospective time trial using a convenience cohort of prehospital providers to determine the success rate for SALT placement (i.e., the basic life support [BLS] phase) and ET placement using the SALT (i.e., the advanced life support [ALS] phase) in an unembalmed human cadaver model. The part 1 cohort (group 1) comprised predominantly basic and intermediate emergency medical technician (EMT)-level providers, whereas the part 2 cohort (group 2) comprised exclusively paramedic-level providers.

RESULTS

In group 1, 51 (98%) of the subjects were able to successfully place the SALT and ventilate the cadaver (BLS phase), with 48 (92.3%) subjects successfully placing it on the first attempt. In group 2, 21 (96%) of the subjects were able to successfully place the SALT, with 19 (86%) placing the SALT on the first attempt. Successful blind placement of an ET through the SALT (ALS phase) by group 1 was 48.1% (95% confidence interval [CI]: 34-62), with 37% (95% CI: 24-51) placing the ET on the first attempt. In group 2, 20 subjects (91% [95% CI: 71-99]) were able to successfully place an ET through the SALT, with 13 (59% [95% CI: 36-79]) doing so on the first attempt.

CONCLUSIONS

Emergency medical services providers of varying levels can successfully and rapidly place the SALT and ventilate a cadaver specimen. The success rate for blind placement of an ET through the SALT was suboptimal.

The Fastrach Intubating Laryngeal Mask Airway: an overview and update

PURPOSE

To provide an evidence-based overview and update on the use of the Fastrach Intubating Laryngeal Mask Airway (FT-LMA) when used within operative and non-operative settings.

PRINCIPAL FINDINGS

The FT-LMA is available in three sizes to provide ventilation and the ability to pass an endotracheal tube (ETT) into the trachea blindly, semi-blindly, or with indirect visualization for patients over 30 kg. The Chandy maneuver is recommended routinely; the first maneuver optimizes ventilation, and the second maneuver increases success at endotracheal intubation (ETI). The manufacturer's reinforced tube or a pre-warmed or reversed standard ETT may be utilized. Insertion and ventilation are successful in almost all patients. Blind ETI is highly successful; adjuncts are generally not necessary. The FT-LMA has a proven role in the airway management of anticipated difficult operating room (OR) intubations, unanticipated OR intubations, cervical spine injuries, and limited airway access situations. Literature in the pre-hospital and emergency department settings is limited but favourable. The FT-LMA has compared favourably with fibreoptic intubation, the LMA-Classic, the laryngeal tube, and the CobraPLA. Initially, the more expensive LMA CTrach appeared to be more successful, but overall it is not. The FT-LMA airway seal pressures are excellent; serious complications are uncommon, and the FT-LMA figures prominently in most difficult airway guidelines.

CONCLUSIONS

The FT-LMA has proven to be a useful difficult airway device both within and outside of the operating room. Effective ventilation is established in nearly all cases, and blind ETI is possible in the vast majority of cases if the optimal techniques described are used. Serious complications are uncommon.

The intuitive use of laryngeal airway tools by first year medical students

Background

Providing a secured airway is of paramount importance in cardiopulmonary resuscitation. Although intubating the trachea is yet seen as gold standard, this technique is still reserved to experienced healthcare professionals. Compared to bag-valve facemask ventilation, however, the insertion of a laryngeal mask airway offers the opportunity to ventilate the patient effectively and can also be placed easily by lay responders. Obviously, it might be inserted without detailed background knowledge.

The purpose of the study was to investigate the intuitive use of airway devices by first-year medical students as well as the effect of a simple, but well-directed training programme. Retention of skills was re-evaluated six months thereafter.

Methods

The insertion of a LMA-Classic and a LMA-Fastrach performed by inexperienced medical students was compared in an airway model. The improvement on their performance after a training programme of overall two hours was examined afterwards.

Results

Prior to any instruction, mean time to correct placement was 55.5 ± 29.6 s for the LMA-Classic and 38.1 ± 24.9 s for the LMA-Fastrach. Following training, time to correct placement decreased significantly with 22.9 ± 13.5 s for the LMA-Classic and 22.9 ± 19.0 s for the LMA-Fastrach, respectively (p < 0.05). After six months, the results are comparable prior (55.6 ± 29.9 vs 43.1 ± 34.7 s) and after a further training period (23.5 ± 13.2 vs 26.6 ± 21.6, p < 0.05).

Conclusion

Untrained laypersons are able to use different airway devices in a manikin and may therefore provide a secured airway even without having any detailed background knowledge about the tool. Minimal theoretical instruction and practical skill training can improve their performance significantly. However, refreshment of knowledge seems justified after six months.

The difficult airway in adult critical care

INTRODUCTION

The difficult airway is a common problem in adult critical care patients. However, the challenge is not just the establishment of a safe airway, but also maintaining that safety over days, weeks, or longer.

AIMS

This review considers the management of the difficult airway in the adult critical care environment. Central themes are the recognition of the potentially difficult airway and the necessary preparation for (and management of) difficult intubation and extubation. Problems associated with tracheostomy tubes and tube displacement are also discussed.

RESULTS

All patients in critical care should initially be viewed as having a potentially difficult airway. They also have less physiological reserve than patients undergoing airway interventions in association with elective surgery. Making the critical care environment as conducive to difficult airway management as the operating room requires planning and teamwork. Extubation of the difficult airway should always be viewed as a potentially difficult reintubation. Tube displacement or obstruction should be strongly suspected in situations of new-onset difficult ventilation.

CONCLUSIONS

Critical care physicians are presented with a significant number of difficult airway problems both during the insertion and removal of the airway. Critical care physicians need to be familiar with the difficult airway algorithms and have skill with relevant airway adjuncts.

Laryngoscopic versus intubating LMA guided tracheal intubation by novice users—A manikin study

AIM OF THE STUDY

Airway control is a potentially lifesaving procedure but tracheal intubation by direct laryngoscopy is difficult. This pilot study was conducted to determine whether tracheal intubation was more rapid and the success rate higher using an intubating laryngeal mask airway.

MATERIAL AND METHODS

The success rates of 119 medical students without prior airway management experience in ventilating and then intubating the trachea of a Laerdal Airway Management Trainer with two different methods were compared. The methods were bag-mask ventilation (BM-V) followed by laryngoscopic intubation (LG-TI), and intubating laryngeal mask ventilation (ILMA-V) followed by ILMA-guided tracheal intubation (ILMA-TI). After an introductory lecture and demonstration, each student was allowed three attempts to intubate using each method in random order.

RESULTS

All participants were successful with BM-V and ILMA-V on the first attempt. Laryngoscopic tracheal intubation was achieved by 60 (50.4%), 31 (26.1%) and 12 (10.1%) participants on the first, second and third attempt, respectively, while 16 (13.4%) failed in all three attempts. In the ILMA-TI group, 107 (90.0%), 10 (8.4%) and 2 (1.6%) succeeded on the first, second and third attempt, respectively. None failed. The intergroup difference is highly significant (p<0.001). Male participants were more successful with LG-TI than female (p<0.01), but not with ILMA-TI.

CONCLUSION

Laryngoscopic orotracheal intubation is difficult for the untrained, but all participants were successful with ILMA-TI. These data suggest that alternative devices such as the ILMA should be included in the medical school curriculum for airway management.

New airways for resuscitation?

Over the last 15 years supraglottic airway devices (SADs), most notably the classic laryngeal mask airway (LMA) have revolutionised airway management in anaesthesia. In contrast for resuscitation, both in and outside hospital, facemask ventilation and tracheal intubation remain the mainstays of airway management. However there is evidence that both these techniques have complications and are often poorly performed by inexperienced personnel. Tracheal intubation also has the potential to cause serious harm or death through unrecognised oesophageal intubation. SADs may have a role in airway management for resuscitation as first responder devices, rescue devices or for use during patient extraction. In particular they may be beneficial as the level of skill required to use the device safely may be less than for the tracheal tube. Concerns have been expressed over the ability to ventilate the lungs successfully and also the risk of aspiration with SADs. The only SADs recommended by ILCOR in its current guidance are the classic LMA and combitube. Several SADs have recently been introduced with claims that ventilation and airway protection is improved. This pragmatic review examines recent developments in SAD technology and the relevance of this to the potential for using SADs during resuscitation. In addition to examining research directly related to resuscitation both on bench models and in patients the review also examines evidence from anaesthetic practice. SADS discussed include the classic, intubating and Proseal LMAs, the combitube, the laryngeal tube, laryngeal tube sonda mark I and II and single use laryngeal masks.

Feasibility of flexible lightwand-guided tracheal intubation with the intubating laryngeal mask during out-of-hospital cardiopulmonary resuscitation by an emergency physician

BACKGROUND AND OBJECTIVE

We tested the feasibility of using the intubating laryngeal mask airway Fastrach (ILMA) as a ventilatory device and for flexible lightwand-guided tracheal intubation for out-of-hospital cardiopulmonary resuscitation by an emergency physician.

METHODS

After completion of a training programme, a single experienced emergency physician used the technique for all patients requiring out-of-hospital tracheal intubation over a 10-month period. If access to the head and neck was limited, the intubating laryngeal mask airway was inserted from below and to the side, otherwise it was inserted from above the head. Data about the time for the ambulance to reach the patient, whether or not access to the head and neck was limited, whether or not circulation was successfully restored, and the insertion and intubation success rates were noted.

RESULTS

The mean (range) time for the ambulance to reach the patient was 12 (10-20) min. Access to the head and neck was limited in 8/37 (22%). Circulation was successfully restored in 10/37 (27%). The intubating laryngeal mask airway was successfully inserted at the first attempt in 35/37 (95%) and at the second attempt in 2/37 (5%). The tracheal tube was successfully inserted in 25/37 (67.5%) at the first attempt, 7/37 (19%) at the second attempt and 5/37 (13.5%) at the third attempt. There were no overall failures for intubating laryngeal mask airway insertion or tracheal intubation. There were no differences in success rate between positions. Oesophageal intubation was detected and corrected in 2/37 (5%).

CONCLUSION

The intubating laryngeal mask airway has a high success rate as a ventilatory device and as a flexible lightwand-guided airway intubator during out-of-hospital cardiopulmonary resuscitation by a well-trained emergency physician. This technique may be particularly useful when there is limited access to the head and neck.

Comparison of airway management with the intubating laryngeal mask, laryngeal tube and CobraPLA by paramedical students in anaesthetized patients

BACKGROUND

Because of the importance of airway management in emergency care, alternative methods with shorter learning curves for inexperienced personnel have been looked for as a substitute for endotracheal intubation (ETI).

METHODS

We compared the success of insertion, oxygenation and ventilation of the intubating laryngeal mask (ILMA), laryngeal tube (LT) and CobraPLA (COB) in anaesthetized patients when used by paramedical students. After informed consent, 96 patients were monitored and anaesthetized for general surgery without the use of a muscle relaxant. After the induction of anaesthesia, 32 paramedical students inserted the ILMA, LT or COB in a random order and ventilated the patient for a 60-s period. The number of insertion attempts, the time needed for insertion, and oxygenation and ventilation parameters were recorded. The students gave a subjective evaluation of the airway devices after the test.

RESULTS

Twenty-four of the 32 students (75%) successfully inserted ILMA at the first attempt, compared with 14 of 32 (44%) for LT and seven of 32 (22%) for COB (P<0.001, ILMA vs. COB). One student failed to insert ILMA after all three attempts, compared with seven of 32 (21%) using LT and seven of 32 (21%) using COB (P=not significant). Oxygenation and ventilation parameters did not differ between the groups after successful insertion.

CONCLUSION

Clinically inexperienced paramedical students can successfully use ILMA in anaesthetized patients. Further investigations are warranted to study whether ILMA or LT can replace ETI in emergency airway management when used by inexperienced medical or paramedical staff.

Intubating laryngeal mask for airway management in lateral decubitus state: comparative study of right and left lateral positions

BACKGROUND

The intubating laryngeal mask has been used for the emergency management of the airway in patients placed in the lateral decubitus position. We have conducted this prospective study to compare the feasibility of placement of an intubating laryngeal mask and blind tracheal intubation guided by the intubating laryngeal mask in patients placed in the right and the left lateral positions.

METHODS

A total of 82 adults of both sexes with normal airways, scheduled for cholecystectomy, were allocated randomly to be placed in either the right (n=41) or left (n=41) lateral position for the insertion of an intubating laryngeal mask and blind tracheal intubation guided by the intubating laryngeal mask under balanced general anaesthesia. A sequence of standard manoeuvres was performed after each failed attempt at intubating laryngeal mask placement and intubation.

RESULTS

The intubating laryngeal mask was placed in all patients at the first attempt. Ventilation of the lungs through the intubating laryngeal mask was possible in 40 patients (97.5%) from each group after the first attempt at insertion (P=1). Following adjustments, adequate ventilation could be achieved in all patients. The first attempt success rates of blind tracheal intubation were 85.3% (35/41) and 87.8% (36/41) in the right and left lateral groups, respectively (P=1). The remaining patients from both groups (except for one patient in the left lateral group who had a failed intubation) were intubated at the second attempt.

CONCLUSION

Insertion of the intubating laryngeal mask and blind tracheal intubation through it in the lateral position is feasible in patients with normal airways. These procedures have a high and comparable success rate when patients are placed in the right and left lateral positions.

The use of laryngeal tube by nurses in out-of-hospital emergencies: Preliminary experience

In out-of-hospital emergencies, including cardiac arrest, securing the airway and providing adequate lung ventilation are of paramount importance. Tracheal intubation is perceived as the gold standard technique and it is recommended by International Guidelines, but non skilled personnel often find the procedure difficult to achieve. Supraglottic devices are a good alternative in these situations, because they are superior to a bag-valve-mask for lung ventilation and offer better protection from aspiration. We have tested the laryngeal tube (LT) in out-of-hospital emergencies by minimally trained nurses. The LT was placed in 30 patients in cardiac arrest. LT insertion was successful within two attempts in 90% of patients, and ventilation was adequate in 80% of cases. No regurgitation occurred in any patient. The laryngeal tube remained in the correct position throughout resuscitation attempts in 93.3% of cases, while in two patients (6.6%) it became dislodged. In a subjective evaluation of the manoeuvre by nurses (ease of insertion, adequacy of ventilation, protection from aspiration), 86.7% of them expressed a positive opinion. The laryngeal tube appeared to be a reliable device for nurses to manage the airway in out-of-hospital emergencies.

Insertion of the endotracheal tube, laryngeal mask airway and oesophageal-tracheal Combitube®. A 6-month comparative prospective study of acquisition and retention skills by medical students

OBJECTIVE

To assess the ability of medical students to learn and retain skills of airway manipulation for insertion of the endotracheal tube, the laryngeal mask airway (Laryngeal Mask Company, Henley-on-Thames, UK) and the oesophageal-tracheal Combitube (Kendall-Sheridan Catheter Corp., Argyle, NY, USA).

METHODS

A 6-month prospective study was conducted among fifth-year medical students attending a 3-week clerkship in the Division of Anesthesiology and Critical Care Medicine in the Soroka Medical Center. All the students viewed a demonstration of insertion technique for the endotracheal tube, the laryngeal mask airway and the Combitube, followed by formal teaching in a mannikin. At the end of the program, the insertion skills were demonstrated in the mannikin, the success rate on the first attempt was registered and the students were requested to assess (by questionnaire) their ability to execute airway manipulation (phase 1). Six months later, the students were requested to repeat the insertion technique, and a similar re-evaluation applied (phase 2).

RESULTS

The success rate, during the first phase, at first attempts was 100% for the laryngeal mask airway and the Combitube, compared to 57.4% for the endotracheal tube (P < 0.02), and 92.6%, 96.2% and 62.9% (P < 0.02) respectively for the second phase of the study.

CONCLUSION

Learning and retention skills of medical students, in a mannikin, are more accentuated with the laryngeal mask airway and the Combitube than seen with an endotracheal tube.

Lightwand-assisted intubation of patients in the lateral decubitus position

In some situations, patients need endotracheal intubation to maintain airway patency while they are constrained in the lateral position. In this study we compared lightwand-guided intubation of 120 randomly enrolled patients placed in the supine, right, or left lateral position. Group S patients were initially placed in the supine position, and subsequent to the artificial airway having been established they were turned to the lateral decubitus position. Group R patients were initially placed in a right decubitus position during induction and intubation. Group L patients were initially placed in a left decubitus position during induction and intubation. The duration of each intubation attempt, the total time to successful intubation, and the incidence of intubation-related intraoral injury, hemodynamic changes, and postoperative sore throat and hoarseness were recorded. Intubation took a similar length of time in the supine (14.5 +/- 13.4 s), left lateral (13.3 +/- 10.2 s), and right lateral positions (15.5 +/- 13.0 s) and resulted in a similar trend in hemodynamic changes. Patients in the lateral and supine positions revealed a comparable incidence of successful first-attempt intubation, sore throat, hoarseness, oral mucosal injury, and dysrhythmia. Insignificantly more esophageal intubations were performed in the lateral position in the first attempt at intubation; however, all patients were correctly intubated shortly after reattempting intubation. We concluded that lightwand-assisted intubation is easily performed and a similar technique may be used whether the patient is in a lateral, recumbent, or a supine position. This alternative technique should be practiced and is recommended for patients who must remain in a lateral position during intubation and surgery.

Preoperative planning of airway management in critical care patients

OBJECTIVE

The aim of this article is to review aspects of airway evaluation that may affect the care of the critical care patient whose airway is to be managed. This information must then be incorporated into the decision-making process of the "airway manager."

DESIGN

Literature review.

RESULTS

Historically used indexes of airway evaluation suffer from low sensitivity and only modest specificity in identifying the difficult-to-intubate patient. Using each index in isolation of others contributes to their poor predictive power. An understanding of anatomical relationships that these indexes measure should help the clinician in evaluating the airway. The clinician's impression of the airway, as well as the likelihood of trouble with supraglottic ventilation, the patient's inability to take food orally, and the patient's general condition can be used to formulate a management plan. This plan should be consistent with the American Society of Anesthesiologist's difficult airway algorithm.

CONCLUSIONS

Rote decision making on airway management, based on commonly used indexes, is not adequate. The vital role of airway in anesthetic management of the critical care patient demands thoughtful consideration. Patient conditions including the need for airway control, the likelihood of difficult laryngoscopy or supraglottic ventilation, the patient's inability to take food orally, and the medical state of the patient must be incorporated.

A comparison of the ProSeal and classic laryngeal mask airways for airway management by inexperienced personnel after manikin-only training

We compared the ProSeal (PLMA) and Classic (LMA) laryngeal mask airway for airway management by inexperienced personnel. Nine nurses from the post-anaesthesia care unit, with no prior experience of LMA or PLMA insertion, were observed inserting the LMA and PLMA in 60 ASA 1 to 2 anaesthetized, paralyzed adults following manikin-only training. The time to achieve an effective airway (2 consecutive expired tidal volumes (6 ml/kg; maximum 2 minutes allowed), the number of insertion attempts and the reasons for failure (inability to insert into pharynx or inadequate ventilation) were determined by analysis of digital video recordings. The first attempt success rate (LMA, 85%; PLMA, 83%), overall success rate (LMA, 88%; PLMA, 90%) and effective airway time (LMA, 39 +/- 13 s; PLMA, 43 +/- 19 s) were similar. Failure was from an inability to insert into the pharynx in five with the LMA and three with the PLMA, and inadequate ventilation with two from the LMA and three from the PLMA. Effective airway time and the number of failures were similar for the first and second device. Failure of both devices occurred in four patients. We conclude that airway management in anaesthetized, paralyzed adults is equally successful for the LMA and PLMA by inexperienced personnel following manikin-only training. The PLMA is worthy of consideration as a tool for emergency airway management by inexperienced personnel.

Training Fourth-Year Medical Students in Critical Invasive Skills Improves Subsequent Patient Safety

Complications after procedures performed by residents are thought to occur most often early in the first postgraduate year (PGY-1). We evaluated the number of pneumothoraces (PTXs) caused by central venous line insertion (CVLI) by two groups of PGY-1 residents in both the first 3 months of residency and the entire year from 1996 through 2000 to determine the impact of CVLI training on PTX. From 1996 through 1998 fourth-year medical students had no specific training in CVLI and learned on the job as residents. Starting with the Class of 1999 we replaced this approach with a structured program in CVLI. Didactic sessions detailing anatomy and technique were followed by skill performance in a fresh cadaver model. Students performed skills initially under the direct supervision of a faculty member, who provided immediate feedback. Videotapes of this performance were reviewed with the students by both surgeons and kinesiologists to correct deficits before repeat sessions. Skills were repeated until competence was attained. Graduating students have made up greater than 90 per cent of our two hospitals’ PGY-1 residents since 1996. Because these residents are responsible for CVLI we are able to obtain performance follow-up in actual clinical settings. We obtained the number of PTXs caused by CVLI for the years 1996 through 2000 as well as for the first 3 months of each academic year (July through September) to determine the impact of our program on this serious complication. The number of PTXs during the first 3 months of 1996–1998 remained stable. After the introduction of our teaching program the number decreased significantly in the years 1999–2000 when compared with 1996–1998 ( P = 0.004, t test). The overall yearly decrease for 1999 versus 1996–1998 approached significance ( P = 0.06). The introduction of a structured teaching program of CVLI skills appears to have a positive impact in reducing morbidity of PTX. The greatest impact occurs within the first 3 months of the new PGY-1 academic year.

Intubating laryngeal mask airway

The Intubating Laryngeal Mask Airway (ILMA) was introduced into clinical practice in 1997 following numerous clinical trials involving 1110 patients. The success rate of blind intubation via the device after two attempts is 88% in "routine" cases. Successful intubation in a variety of difficult airway scenarios, including awake intubation, has been described, with the overall success rate in the 377 patients reported being approximately 98%. The use of the ILMA by the novice operator has also been investigated with conflicting reports as to its suitability for emergency intubation in this setting. Blind versus visualized intubation techniques have also been investigated. These techniques may provide some benefits in improved safety and success rates, although the evidence is not definitive. The use of a visualizing technique is recommended, especially whilst experience with intubation via the ILMA is being gained. The risk of oesophageal intubation is reported as 5% and one death has been described secondary to the complications of oesophageal perforation during blind intubation. Morbidity described with the use of the ILMA includes sore throat, hoarse voice and epiglottic oedema. Haemodynamic changes associated with intubation via the ILMA are of minimal clinical consequence. The ILMA is a valuable adjunct to the airway management armamentarium, especially in cases of difficult airway management. Success with the device is more likely if the head of the patient is maintained in the neutral position, when the operator has practised at least 20 previous insertions and when the accompanying lubricated armoured tube is used.

Airway management outside the operating room

The choice of airway device for resuscitation depends on the skill of the user, the equipment available, the conscious state of the patient, the location of the patient and the probable cause of the cardiorespiratory arrest. Extraglottic airway devices are recommended by the European and American Resuscitation Councils for use when intubation skills are lacking. In this review, we discuss recent research relevant to the use of extraglottic airway devices in resuscitation.

Difficult airway management in the emergency department

Most airway management in the emergency department is straightforward and readily accomplished by the emergency physician. The exact incidence of difficult intubations is difficult to discern from available evidence, but these are probably more frequent in the Emergency Department than in the operating room, given the urgent nature of the procedure and the lack of preparation of the patient population. A variety of adjuncts for airway management are available to assist in both intubation and ventilation. The utility of these adjuncts is detailed in this review, with emphasis on techniques most useful to the emergency physician.

Laryngeal mask vs intubating laryngeal mask: insertion and ventilation by inexperienced resuscitators

The laryngeal mask airway (LMA) has been shown to be useful in airway maintenance during resuscitation. The intubating laryngeal mask (ILM) is a modified LMA permitting both ventilation and rapid endotracheal intubation. We aimed to compare the LMA and the ILM with regard to ease of insertion and successful ventilation by inexperienced personnel. We have used anaesthetized, apnoeic, non-paralysed patients as a model to simulate resuscitation. Following standardized training, non-anaesthetic medical staff with no previous experience in laryngeal mask airway insertion (novices) inserted either the LMA or ILM in 55 patients following induction of anaesthesia. There were no differences between the two patient groups included in our study with regard to mean age and body mass index (BMI). The success rate for inserting the airway device and achieving a significant end-tidal CO2 recording within two minutes was 23/28 for the LMA (82.1%) and 22/27 for the ILM (81.5%). Reasons for failure included inability to insert the ILM past the teeth and insertion of the LMA upside down. There were no clinically relevant differences in the mean time to airway insertion and successful ventilation (62.6 vs 62 seconds) or expired tidal volume (781 vs 767 ml) for the LMA and ILM respectively. We conclude that the ILM is as easily inserted and effectively used as an LMA by novices and, because it allows the option offacilitating endotracheal intubation, may be the preferred device for maintaining an airway during resuscitation.

Initial experience of emergency physicians using the intubating laryngeal mask airway: a case series

OBJECTIVE

Although the intubating laryngeal mask airway (ILMA) is widely available, its use by emergency physicians (EPs) has not been reported. The authors report the initial experience of EPs using the ILMA. A review of their experience and the relevant anesthesia literature provides a basis for EPs to use the ILMA more confidently and effectively.

METHODS

Between January 2000 and January 2001, the ILMA was used on a convenience sample of emergency department (ED) patients undergoing "routine" intubations, and "rescue" situations, after failed rapid-sequence intubation (RSI). Patients were identified from the ED resuscitation case database. Chart review and intubating physician interviews focused on success of the device, complications encountered, and "pearls" of the device's use as perceived by the intubating physician.

RESULTS

Ventilation with the appropriate-size ILMA occurred in less than 15 seconds in all "routine" intubations; tracheal intubation was subsequently accomplished in less than 1 minute. Eight of nine "routine" patients had blind tracheal intubation through the ILMA. One patient required fiberoptic bronchoscopy to guide the endotracheal tube into the trachea. Of the "rescue" intubations, all patients (n = 7) were successfully ventilated and five were successfully intubated using the ILMA.

CONCLUSIONS

In this case series, the ILMA was easy to use in acute resuscitations, and proved to be invaluable in cases of failed RSI.

A comparison of the intubating and standard laryngeal mask airways for airway management by inexperienced personnel

Twenty-four inexperienced participants were timed inserting the intubating laryngeal mask airway and the laryngeal mask airway in 75 anaesthetised subjects. Adequacy of ventilation was assessed on a three-point scale. The pressure at which a leak first developed around the device's cuff was also measured. There was no significant difference in insertion time or the likelihood of achieving adequate ventilation between devices. However, the intubating laryngeal mask airway was better at providing adequate ventilation without audible leak (58/75 (77%) vs. 42/75 (56%); p = 0.009). The median (range [IQR]) pressure at which an audible leak developed was higher for the intubating laryngeal mask airway, 34.5 (14-40 [29-40]) cmH2O, than for the laryngeal mask airway, 27.5 (14-40 [22-33]) cmH2O (p < 0.001). The intubating laryngeal mask airway is worthy of further consideration as a tool for emergency airway management for inexperienced personnel.

New equipment and techniques for airway management in trauma

A patent, unobstructed airway is fundamental in the care of the trauma patient, and is most often obtained by placing a cuffed tube in the trachea. The presence of shock, respiratory distress, a full stomach, maxillofacial trauma, neck hematoma, laryngeal disruption, cervical spine instability, and head injury all combine to increase tracheal intubation difficulty in the trauma patient. Complications resulting from intubation difficulties include brain injury, aspiration, trauma to the airway, and death. The use of devices such as the gum-elastic bougie, McCoy laryngoscope, flexible and rigid fiberscopes, intubating laryngeal mask, light wand, and techniques such as rapid-sequence intubation, manual in-line axial stabilization, retrograde intubation, and cricothyroidotomy, enhance the ability to obtain a definitive airway safely. The management of the failed airway includes calling for assistance, optimal two-person bag-mask ventilation, and the use of the laryngeal mask airway, Combitube, or surgical airway. The simulation of airway management using realistic simulator tools (e.g. full-scale simulators, virtual reality airway simulators) is a promising modality for teaching physicians and advanced life support personnel emergency airway management skills.