We read with great interest the anesthetic technique of using a gum elastic bougie (GEB) for nasal intubation in a recent issue of Anesthesia Progress. The authors recommend the use of GEB for the first attempt of nasotracheal intubation in patients with a difficult airway. We agree that this is an excellent alternative. We also have found an excellent variation of this method that utilizes a double bougie technique for insertion of a nasotracheal tube if the difficult airway can be secured initially with an orotracheal tube.
Dual bougie technique; Nasotracheal intubation
The ProSeal laryngeal mask airway (PLMA) is a unique laryngeal mask with a modified cuff to improve seal and a channel to facilitate gastric tube placement. This is a better device in difficult airway situations compared to classic laryngeal mask airway. This prompted us to study the ease of insertion and positioning of PLMA in patients with simulated restricted neck mobility while using gum elastic bougie (GEB) group or introducer tool (group IT) to aid insertion.
Sixty ASA I or II patients, aged between 18 years and 60 years, undergoing minor non-head and neck surgeries in the supine position were studied. A rigid neck collar was used to simulate restricted neck mobility in all patients. After anaesthetising the patients with a standard protocol, the PLMA was inserted using either of the technique using the tongue depressor to open the mouth. The ease of insertion, positioning, haemodynamic responses to insertion and other complications related to the procedure were noted.
Regarding demographic variables, both groups were similar. The mean time taken for insertion of PLMA in group GEB was 67.80 s as compared to 46.79 s in group IT (P<0.05). Patients of group GEB had better positioning assessed by an intubating fiberscope with less end tidal carbon-di-oxide (ETCO2) values. Systolic and diastolic blood pressures were similar. The incidence of sore throat, dysphagia, and dysphonia were higher in IT group in the 12 h, but similar in 24 h.
Guided insertion technique with GEB took a longer time, but had a better positioning and lower ETCO2 values when compared to IT technique.
Difficult airway; gum elastic bougie; ProSeal laryngeal mask; simulation
The Proseal™ laryngeal mask airway (PLMA™, Laryngeal Mask Company, UK) was designed to improve ventilatory characteristics and offer protection against regurgitation and gastric insufflation. The PLMA is a modified laryngeal mask airway with large ventral cuff, dorsal cuff and a drain tube. These modifications improve seal around glottis and enable better ventilatory characteristics. The drain tube prevents gastric distension and offers protection against aspiration. There were occasional problems, like failed insertion and inadequate ventilation, in placing PLMA™ using the classical digital technique. To overcome these problems, newer placement techniques like thumb insertion technique, introducer tool placement and gum elastic bougie (GEB)-aided placement were devised. We compared classical digital placement of PLMA™ with gum elastic bougie-aided technique in 60 anaesthetised adult patients (with 30 patients in each group) with respect to number of attempts to successful placement, effective airway time, airway trauma during insertion, postoperative airway morbidity and haemodynamic response to insertion. The number of attempts to successful placement, airway trauma during insertion and haemodynamic response to insertion were comparable among the two groups, while effective airway time and oropharyngeal leak pressure were significantly higher in bougie- guided insertion of PLMA. Postoperatively, sore throat was more frequent with digital technique while dysphagia was more frequent with bougie guided technique. Hence gum elastic bougie guided, laryngoscope aided insertion of PLMA is an excellent alternate to classical digital technique.
Anaesthesia; airway; equipment; laryngeal masks; technique; oropharyngeal seal pressure
We report the case of a 30 year old man managed in an out of hospital setting for a cardiorespiratory arrest. The patient was impossible to intubate under direct laryngoscopy because of a severe mouth opening limitation associated with a buffalo neck. After failure of direct laryngoscopy and intubating laryngeal mask airway, an Eschmann tracheal tube introducer (gum elastic bougie) was introduced through a nostril. The bougie could be blindly inserted into the trachea, and the patient was intubated using the bougie as a guide. Tracheal intubation was then confirmed using the syringe aspiration test and end tidal carbon dioxide detection.
out of hospital; cardiopulmonary resuscitation; airway management; difficult intubation
The airway scope (AWS) improves views of the larynx during orotracheal intubation. However, the role of the AWS in routine nasotracheal intubation has not been studied adequately.
One hundred and three patients undergoing dental and maxillofacial surgery that required general anesthesia and nasotracheal intubation were enrolled. The study was approved by our Institution Review Board, and written informed consent was obtained from all patients. We evaluated the success rate of AWS intubation and the incidence of difficult nasotracheal intubation using a modified intubation difficulty scale (IDS) to examine preoperative characteristics and intubation profiles. Categories were difficult intubation (IDS ≥5), mildly difficult (IDS = 1–4), and intubation without difficulty (IDS = 0). We also assessed the incidence of the use of Magill forceps or cuff inflation (the cuff of endotracheal tube is inflated with 10–15 ml air) to guide the endotracheal tube into the glottis.
AWS nasotracheal intubation was 100 % successful. The cuff inflation technique was used in 37 patients. Neither Magill forceps nor other devices were needed for any patient during AWS use. The incidence of difficult nasotracheal intubation was 10 % (n = 10). Of the patients, 61 % (n = 63) had mildly difficult intubation and 29 % (n = 30) had no difficulty. Patients with difficult intubation were more likely to be male and to have a larger tongue and a higher Cormack grade than in the other two groups. Complications, involving minor soft tissue injury, were observed in only 1 patient (1 %).
The AWS achieves a high success rate for nasotracheal intubation with cuff inflation in patients undergoing dental and maxillofacial surgery.
Airway scope; Video laryngoscope; Difficult nasotracheal intubation
The laryngeal mask airway-ProSeal™ can be inserted digitally, by introducer tool, or by railroading it over a bougie placed first in the patient's oesophagus, which is highly successful, but as originally described, requires an assistant. An unassisted bougie-guided placement technique has also been described, but no data on its effectiveness have been reported.
We reviewed data collected during a randomized, controlled trial comparing the air-Q® Intubating Laryngeal Airway and LMA-Proseal™, in which all LMA-Proseal™ devices were inserted using the unassisted (one-operator), bougie-guided placement technique.
Forty-eight devices were placed. All devices were placed successfully. Successful placement was achieved in 47 (98%) patients on first attempt and in one (2%) patient on the third attempt. Mean (SD) time required for insertion establishing ventilation was 28 (11) s. Mean (SD) airway seal pressure was 30 (6) cmH2O. Gross blood was found on four (8%) devices upon removal, but no oropharyngeal injuries were noted on oral exam in the recovery unit prior to discharge. The most common complaints in recovery and 24 h post-operatively were sore throat [discharge: mild = 18/48 (38%); 24 h: mild = 9/38 (19%), moderate = 1/38 (3%)] and pain on swallowing [discharge: mild = 7/48 (15%); 24 h: mild = 2/38 (6%)].
Our data confirm that in experienced hands, bougie-guided placement of the LMA-Proseal™ without the aid of an assistant can be accomplished quickly and successfully without affecting the expected clinical performance of the device.
Bougie; insertion; LMA; Proseal
Morbidly obese patients are at increased risk of difficult mask ventilation and intubation as well as increased risk of hypoxemia during tracheal intubation. Recently, new video-assisted intubation devices have been developed. The GlideScope® videolaryngoscope and LMA CTrach™ (CT) allows continuous video-endoscopy of the tracheal intubation procedure.
this study is to determine whether the GlideScope® videolaryngoscope (GVL) and the LMA CTrach™ (CT) provide the best airway management, measured primarily in intubation difficulty scale (IDS) scores, time and numbers of intubation attempts, and improvement in the intubation success rate of morbidly obese patients when compared with the direct Macintosh laryngoscope (DL).
Materials and Methods:
After Ethics’ Committee approval, 90 morbidly obese patients (BMI > 35 kg/m2) scheduled for general, gynecological, and bariatric surgery were included in this prospective study. Patients were randomly assigned in three groups: tracheal intubation using direct laryngoscopy (DL), GlideScope® videolaryngoscope (GVL) or the LMA CTrach™ (CT). Characteristics and consequences of airway management were evaluated. The primary outcome was the intubation difficulty scale score (IDS), Secondary outcomes were theintubation time, overall success rate, number of attempts, Cormack–Lehane grade, subjective difficulty of intubation, desaturation and upper airway morbidity.
Difficulty in facemask ventilation was similar in the three groups. IDS scores were significantly lower with GVL and CT than with DL. The mean TTI was 14 s faster in patients intubated with the GVL (86 s, IQR: 68-115) compared with DL (100 s, IQR; 80-150), and was 34 s faster when compared with CT (120 s, IQR; 95-180). The success rate of tracheal intubation was lower with the DL (80%) compared with the GVL (100%) or the CT (100%). Six cases of failed intubation occurred in group DL, four patients from the six patients were intubated successfully with GVL, and two patients were intubated with the CT. Both the GVL and the CTimproved the Cormack and Lehane view obtained at laryngoscopy, compared with the DL. Significantly high percent of patients in DL (43%) and CT (27%) required optimization maneuvers (external laryngeal pressure) compared with GVL (0%). In the CT group, 30% of the patients required laryngeal mask manipulation (for view optimization) compared with (0%) in GVL and CT groups.
The GlideScope® videolaryngoscope and the LMA CTrach™ reduced the difficulty, improved laryngoscopic views and overall success rate of tracheal Intubationto a similar extent compared with the Macintosh laryngoscope in morbidly obese patients. The GVL improved intubation time for tracheal intubation compared with the CT and DL but no patient became hypoxic with CT because of prolonged intubation time.
GlideScope® videolaryngoscope; LMA CTrach™; Macintosh laryngoscope; morbid obese patients; tracheal intubation
Although Lightwand and Glidescope have both shown high success rates for intubation, there has been no confirmation as to which device is most effective for difficult endotracheal intubation. We compared the Glidescope and Lightwand devices in terms of duration of intubation and success rate at the first attempt in a simulated difficult airway situation.
Fifty-eight patients were randomized to undergo tracheal intubation with either the Glidescope (Glidescope group, n = 29) or the Lightwand (Lightwand group, n = 29). All patients were fitted with a semi-hard cervical collar in order to simulate a difficult airway, and intubation was attempted with the assigned airway device. The data collected included the rate of successful endotracheal intubation, the number of attempts required, the duration of the intubation, as well as the interincisor distance, hemodynamic variables, and adverse effects.
There was no difference between Glidescope group (92.6%) and Lightwand group (96.4%) in terms of success rate for the first attempt at intubation. The duration of successful intubation for the first tracheal intubation attempt was significantly longer in Glidescope group than in Lightwand group (46.9 sec vs 29.5 sec, P = 0.001). All intubations were completed successfully within two intubation attempts. The incidence of hypertension was significantly higher in Glidescope group than in Lightwand group (51.9% vs 17.9%, P = 0.008).
In a simulated difficult airway situation, endotracheal intubation using Lightwand yielded a shorter duration of intubation and lower incidence of hypertension than when using Glidescope.
Airway management; Intubation; Laryngoscopes; Light; Transillumination
The enlarged adenoid serves as a mechanical obstacle on the nasopharynx to intricate nasotracheal intubation. No matter what video or direct laryngoscopic techniques are applied, nasotracheal tube navigation from the nasal valve area through the nasal cavity to the nasopharynx is always blind; trauma is not uncommon. Here we report a case of unintended avulsed adenoids that plugged the tube tip while the nasotracheal tube blindly navigated through the nasopharyngeal space. After failing to insert a bent tip of gum elastic bougie passing through the nasopharynx, an alternative method of NTI was performed by mounting the nasotracheal tube on a fiberoptic bronchoscope. The nasotracheal tube was successfully railroaded along the insertion tube of the fiberscope to the trachea.
The Truview™ EVO2 laryngoscope, with its unique optical lens system and blade tip angulation, has proved its usefulness in providing adequate laryngeal exposure and intubation via the oral route. However, the same has not been evaluated for nasotracheal intubation.
We evaluated the suitability of the Truview™ EVO2 laryngoscope for nasotracheal intubation.
Fifty ASA grade I and II elective surgical patients were studied. Patients aged below 15 years or having difficult airway were excluded. Under standard anesthesia protocol, nasotracheal intubation was performed using a Truview™ EVO2 laryngoscope and, in cases of inability to complete intubation in three attempts, the Macintosh laryngoscope was used. Time taken for intubation, use of Magill's forceps and need for optimization maneuvers were noted. The primary outcome was percentage of successful intubation, while hemodynamic changes and duration of intubation were taken as secondary outcomes.
Majority (94%) could be intubated successfully with the Truview™ EVO2 laryngoscope. Average time taken for intubation was 50.1 s. The hemodynamic changes were not clinically significant. Regression analysis revealed lack of association between duration of intubation and hemodynamic changes. There were no serious complications.
The Truview™ EVO2 laryngoscope is a useful tool in performing nasotracheal intubation, ensuring a high level of success rate among patients with normal airway anatomy.
Laryngoscope; orthognathic surgery; nasotracheal intubation; Truview™ EVO2
The placement of endotracheal tubes in the airway, particularly through the nose, can cause trauma. Their design might be an important etiologic factor, but they have changed little since their introduction. Recently Parker Medical (Bridgewater, Conn ) introduced the Parker Flex-Tip (PFT) tube, suggesting that it causes less trauma. This study aimed to compare the PFT endotracheal tube to a side-beveled, standard-tip endotracheal tube (ETT) for nasotracheal intubation (Figures 1 and 2). Forty consecutive oral surgery patients requiring nasotracheal intubation were randomized to receive either a standard ETT or the PFT tube. Intubations were recorded using a fiber-optic camera positioned proximal to the Murphy eye of the tube. This allowed visualization of the path and action of the tube tip as it traversed the nasal, pharyngeal, laryngeal, and tracheal airway regions. Video recordings made during intubation and extubation were evaluated for bleeding, trauma, and intubation time. Both bleeding and trauma were recorded using a visual analogue scale (VAS) and by 3 different evaluators. The PFT received significantly better VAS values than the standard tubes from all 3 raters (P < 0.05) in both the extent of trauma and bleeding. Since the intubations were purposefully conducted slowly for photographic reasons, neither tube displayed a time advantage. This study suggests that the PFT tube design may be safer by causing less trauma and bleeding than standard tube designs for nasotracheal intubation.
Nasotracheal intubation; Parker Flex-Tip tube; Endotracheal intubation; Endotracheal tube; Fiber-optic intubation
Introduction: Blind nasotracheal intubation is an intubation method without observation of glottis that is used when the orotracheal intubation is difficult or impossible. One of the methods to minimize trauma to the nasal cavity is to soften the endotracheal tube through warming. Our aim in this study was to evaluate endotracheal intubation using endotracheal tubes softened by hot water at 50 °C and to compare the patients in terms of success rate and complications.
Methods: 60 patients with ASA Class I and II scheduled to undergo elective jaw and mouth surgeries under general anesthesia were recruited.
Results: success rate for Blind nasotracheal intubation in the control group was 70% vs. 83.3% in the study group. Although the success rate in the study group was higher than the control group, this difference was not statistically significant. The most frequent position of nasotracheal intubation tube was tracheal followed by esophageal and anterior positions, respectively.
Conclusion:In conclusion, our study showed that using an endotracheal tube softened by warm water could reduce the incidence and severity of epistaxis during blind nasotracheal intubation; however it could not facilitate blind nasotracheal intubation.
Blind Intubation; Warming; Endotracheal Tube; Oral and Maxillofacial Surgery; Anesthesia
A critical aspect of safe general anesthesia is providing adequate ventilation and oxygenation. Failed endotracheal intubation and inadequate ventilation with insufficient oxygenation may lead to serious complications, even death. Anesthesiologists rarely encounter unexpected difficult airway problems in daily routine. Management of an unexpectedly difficult airway consists of laryngeal mask ventilation, gum-elastic bougie and video laryngoscopy-assisted intubation. Gum-elastic bougie is the easiest and cheapest tool used in case of an unexpected difficult intubation occurring in the operating room.
A 53-year-old male patient with hypogonadotropic hypogonadism presented as an unexpected difficult intubation after the induction of anesthesia. No pathological finding or predictor of difficult intubation was present. In addition, bag-mask ventilation was poor and inadequate. The patient was finally successfully intubated with a gum-elastic bougie.
A difficult airway has been described in patients with a variety of endocrine disorders, including pituitary diseases, but not with hypogonadism. There may be an unrevealed relationship between hypogonadism and difficult airway. Gum-elastic bougie is still the most attainable and effective tool in the operation room in this situation.
airway management; intubation; hypogonadism
Oromaxillofacial surgical procedures present a unique set of problems both for the surgeon and for the anesthesist. Achieving dental occlusion is one of the fundamental aims of most oromaxillofacial procedures. Oral intubation precludes this surgical prerequisite of checking dental occlusion. Having the tube in the field of surgery is often disturbing for the surgeon too, especially in the patient for whom skull base surgery is planned. Nasotracheal intubation is usually contraindicated in the presence of nasal bone fractures seen either in isolation or as a component of Le Fort fractures. We utilized submental endotracheal intubation in such situations and the experience has been very satisfying.
Materials and Methods:
The technique has been used in 20 patients with maxillofacial injuries and those requiring Le Fort I approach with or without maxillary swing for skull base tumors. Initial oral intubation is done with a flexo-metallic tube. A small 1.5 cm incision is given in the submental region and a blunt tunnel is created in the floor of the mouth staying close to the lingual surface of mandible and a small opening is made in the mucosa. The tracheal end of tube is stabilized with Magil′s forceps, and the proximal end is brought out through submental incision by using a blunt hemostat taking care not to injure the pilot balloon. At the end of procedure extubation is done through submental location only.
The technique of submental intubation was used in a series of twenty patients from January 2005 to date. There were fifteen male patients and five female patients with a mean age of twenty seven years (range 10 to 52). Seven patients had Le Fort I osteotomy as part of the approach for skull base surgery. Twelve patients had midfacial fractures at the Le Fort II level, of which 8 patients in addition had naso-ethomoidal fractures and 10 patients an associated fracture mandible. Twelve patients were extubated in the theatre. Eight patients had delayed extubation in the post-operative ward between 1 and 3 days postoperatively.
In conclusion, the submental intubation technique has proved to be a simple solution for many a difficult problem one would encounter during oromaxillofacial surgical procedures. It provides a safe and reliable route for the endotracheal tube during intubation while staying clear of the surgical field and permitting the checking of the dental occlusion, all without causing any significant morbidity for the patient. Its usefulness both in the emergency setting and for elective procedures has been proved. The simplicity of the technique with no specialized equipment or technical expertise required makes it especially advantageous. This technique therefore, when used in appropriate cases, allows both the surgeon and the anesthetist deliver a better quality of patient care.
Avoiding tracheostomy; oromaxillofacial surgery; intubation
A wire-reinforced silicone tube (LMA-Fastrach™ endotracheal tube) is specially designed for tracheal intubation using intubating laryngeal mask airway (ILMA). However, conventional polyvinyl chloride (PVC) tracheal tubes have also been used with ILMA to achieve tracheal intubation successfully.
To evaluate the success of tracheal intubation using the LMA-Fastrach™ tracheal tube versus conventional PVC tracheal tube through ILMA.
Settings and Design:
Two hundred adult ASA physical status I/II patients, scheduled to undergo elective surgery under general anaesthesia requiring intubation, were randomly allocated into two groups.
The number of attempts, time taken, and manoeuvres employed to accomplish tracheal intubation were compared using conventional PVC tubes (group I) and LMA-Fastrach™ wire-reinforced silicone tubes (group II). Intraoperative haemodynamic changes and evidence of trauma and postoperative incidence of sore throat and hoarseness, were compared between the groups.
The data was analyzed using two Student's t test and Chi-square test for demographics and haemodynamic parameters. Mann Whitney U test was used for comparison of time taken for endotracheal tube insertion. Fisher's exact test was used to compare postoperative complications.
Rate of successful tracheal intubation and haemodynamic variables were comparable between the groups. Time taken for tracheal intubation and manoeuvres required to accomplish successful endotracheal intubation, however, were significantly greater in group I than group II (14.71±6.21 s and 10.04±4.49 s, respectively (P<0.001), and 28% in group I and 3% in group II, respectively (P<0.05)).
Conventional PVC tube can be safely used for tracheal intubation through the ILMA.
Fastrach; intubating laryngeal mask airway; polyvinyl chloride; tracheal intubation
A variety of videolaryngoscopes with angulated blade have been recently introduced into clinical practice. They provide an indirect view of the glottic structures in normal and challenging clinical settings. Despite the very good visualization of the laryngeal structures by these devices, the insertion and advancement of the endotracheal tube may be prolonged and occasionally fail as it does not conform to the enhanced angulation of the blade. To overcome this handicap, it is recommended to use a pre-shaped, styleted tracheal tube during intubation. Unfortunately, these malleable rigid stylets permit only a fixed shape to the advancing endotracheal tube. This may necessitate withdrawal of endotracheal tube-stylet assembly for reshaping, before undertaking a new attempt. This may cause soft tissue injury and hemodynamic disturbance.
This single-blinded randomized clinical trial aims to overcome these handicaps using a novel method of dynamically changing the shape of the advancing endotracheal tube by Truflex™ articulating stylet as per need during D-blade C-Mac™ videolaryngoscopy.
One hundred and fifty four patients between 18 and 60 years of age belonging to either sex undergoing tracheal intubation under uniform general anesthetic technique will be randomly divided into Portex™ malleable stylet group and Truflex™ articulating stylet group. The primary efficacy variable of success/failure between the two groups will be analyzed using the chi square test. For comparison of intubation times and the Intubation Difficulty Score, ANOVA will be used. Primary efficacy endpoint results will be successful or failed tracheal intubation in the first attempt, total intubation time and the intubation difficulty score. Secondary efficacy endpoints will be overall user satisfaction graded from 1 to 10 (1 = very poor, 10 = excellent), Cormack and Lehane’s grading, glotticoscopy time and ETT negotiation time and total number of intubation attempts. Result of safety endpoints will include dental and airway trauma, hemodynamic disturbances, arrhythmias or cardiac arrest.
Current Controlled Trials ISRCTN57679531; Date of registration 12/02/2013
Videolaryngoscope; Tracheal intubation; Truflex stylet
Background and Aim:
Obtaining patent airway is a crucial task for many physicians. When opportunities to practice intubations on patients are really limited, skill gaining methods are needed. We conducted a study among novice 6th year medical students to assess their ability to intubate the trachea in normal airway in manikin using four airway tools.
Setting and Design:
Prospective, cohort study conducted at simulation center of university-based, tertiary care hospital.
Fifty medical students performed either oral or nasal tracheal intubation using the following four intubating tools: C-Mac videolaryngoscope, Glidescope, and Airtraq in comparison with regular Macintosh laryngoscope. Intubation time, visualization of glottic opening, ease of intubation, satisfaction of participants, incidence of dental trauma, and the need for optimization manoeuvres′ use among different airway tools were recorded.
In oral intubation, Airtraq was better than others in regard to intubation time, glottic opening, ease of intubation, and the need for external laryngeal pressure application, followed by Glidescope, C-Mac, and finally Macintosh laryngoscope (P<0.001). Airtraq and Glidescope associated with less dental trauma than C-Mac and Macintosh. In nasal route, fastest intubation time was reported with Airtraq followed by Glidescope, C-Mac, and lastly Macintosh. Airtraq, Glidescope, and C-Mac were similar to each other and better than the Macintosh in regard to ease of intubation, satisfaction, and number of attempts (P≤0.008).
New devices like Airtraq, Glidescope, and C-Mac are better than the regular Macintosh when used by novice medical students for oral and nasal intubation on manikin.
Airtraq; airway tools; C-Mac video laryngoscope; Glidescope; Macintosh laryngoscope; medical students
One of the methods proposed in cases of difficult airway management in children is using a supraglottic airway device as a conduit for tracheal intubation. The aim of this study was to compare the efficacy of the Air-Q Intubating Laryngeal Airway (Air-Q) and the Cobra Perilaryngeal Airway (CobraPLA) to function as a conduit for fiber optic-guided tracheal intubation in pediatric patients.
Materials and Methods:
A total of 60 children with ages ranging from 1 to 6 years, undergoing elective surgery, were randomized to have their airway managed with either an Air-Q or CobraPLA. Outcomes recorded were the success rate, time and number of attempts required for fiber optic-guided intubation and the time required for device removal after intubation. We also recorded airway leak pressure (ALP), fiber optic grade of glottic view and occurrence of complications.
Both devices were successfully inserted in all patients. The intubation success rate was comparable with the Air-Q and the CobraPLA (96.7% vs. 90%), as was the first attempt success rate (90% vs. 80%). The intubation time was significantly longer with the CobraPLA (29.5 ± 10.9 s vs. 23.2 ± 9.8 s; P < 0.05), but the device removal time was comparable in the two groups. The CobraPLA showed a significantly higher ALP (20.8 ± 5.2 cmH2O vs. 16.3 ± 4.5 cmH2O; P < 0.001), but the fiber optic grade of glottic view was comparable with the two devices. The CobraPLA was associated with a significantly higher incidence of blood staining of the device on removal and post-operative sore throat.
Both the Air-Q and CobraPLA can be used effectively as a conduit for fiber optic-guided tracheal intubation in children. However, the Air-Q proved to be superior due to a shorter intubation time and less airway morbidity compared with the CobraPLA.
Air-Q intubating laryngeal airway; cobra perilaryngeal airway; fiber optic-guided intubation; pediatric airway management; supraglottic airway devices
Video-laryngoscopes are marketed for intubation in difficult airway management. They provide a better view of the larynx and may facilitate tracheal intubation, but there is no adequately powered study comparing different types of video-laryngoscopes in a difficult airway scenario or in a simulated difficult airway situation.
The objective of this trial is to evaluate and to compare the clinical performance of three video-laryngoscopes with a guiding channel for intubation (Airtraq™, A. P. Advance™, King Vision™) and three video-laryngoscopes without an integrated tracheal tube guidance (C-MAC™, GlideScope™, McGrath™) in a simulated difficult airway situation in surgical patients. The working hypothesis is that each video-laryngoscope provides at least a 90% first intubation success rate (lower limit of the 95% confidence interval >0.9). It is a prospective, patient-blinded, multicenter, randomized controlled trial in 720 patients who are scheduled for elective surgery under general anesthesia, requiring tracheal intubation at one of the three participating hospitals. A difficult airway will be created using an extrication collar and taping the patients’ head on the operating table to substantially reduce mouth opening and to minimize neck movement. Tracheal intubation will be performed with the help of one of the six devices according to randomization. Insertion success, time necessary for intubation, Cormack-Lehane grade and percentage of glottic opening (POGO) score at laryngoscopy, optimization maneuvers required to aid tracheal intubation, adverse events and technical problems will be recorded. Primary outcome is intubation success at first attempt.
We will simulate the difficult airway and evaluate different video-laryngoscopes in this highly realistic and clinically challenging scenario, independently from manufacturers of the devices. Because of the sufficiently powered multicenter design this study will deliver important and cutting-edge results that will help clinicians decide which device to use for intubation of the expected and unexpected difficult airway.
Video-laryngoscope; Difficult airway; Airtraq; A. P. Advance; C-MAC; Glidescope; King vision; Mcgrath
GlideScope® videolaryngoscopy (GVL) has been shown to improve visualization of the glottis compared to direct laryngoscopy (DL). However, due to the angle of approach to the glottis, intubation can still be challenging. We hypothesized that novice GVL users would be able to intubate faster and easier using an airway introducer (frequently known as a bougie) than with a standard intubating stylet.
Intubations were performed on a human airway simulator with settings for easy and difficult airways. Participants were emergency medicine (EM) residents or faculty (n=21) who were novice GVL users. Participants were intubated a total of eight times (four GVL, four DL) using either a bougie or an intubating stylet. We recorded time to intubate (TTI) and difficulty rating using a visual analog scale (VAS) and non-parametric statistical methods for analysis. We reported medians with interquartile range (IQR).
The median TTI with difficult airway settings and the bougie-GVL was 76 seconds (IQR 50, 102) versus 64 seconds (IQR 50.5, 125), p=0.76 for the stylet-GVL combination. The median VAS difficulty score, on difficult airway settings, for the bougie-GVL was 5 cm (IQR 3.3, 8.0) versus 6.2 cm (IQR 5.0, 7.5) with the stylet-GVL, p=0.53.
Among novices using GVL for simulated difficult airway management, there was no benefit, in terms of speed or ease of intubation, by using the bougie over the standard stylet.
Previously active in the mid-1990s, the Canadian Airway Focus Group (CAFG) studied the unanticipated difficult airway and made recommendations on management in a 1998 publication. The CAFG has since reconvened to examine more recent scientific literature on airway management. The Focus Group’s mandate for this article was to arrive at updated practice recommendations for management of the unconscious/induced patient in whom difficult or failed tracheal intubation is encountered.
Nineteen clinicians with backgrounds in anesthesia, emergency medicine, and intensive care joined this iteration of the CAFG. Each member was assigned topics and conducted reviews of Medline, EMBASE, and Cochrane databases. Results were presented and discussed during multiple teleconferences and two face-to-face meetings. When appropriate, evidence- or consensus-based recommendations were made together with assigned levels of evidence modelled after previously published criteria.
The clinician must be aware of the potential for harm to the patient that can occur with multiple attempts at tracheal intubation. This likelihood can be minimized by moving early from an unsuccessful primary intubation technique to an alternative “Plan B” technique if oxygenation by face mask or ventilation using a supraglottic device is non-problematic. Irrespective of the technique(s) used, failure to achieve successful tracheal intubation in a maximum of three attempts defines failed tracheal intubation and signals the need to engage an exit strategy. Failure to oxygenate by face mask or supraglottic device ventilation occurring in conjunction with failed tracheal intubation defines a failed oxygenation, “cannot intubate, cannot oxygenate” situation. Cricothyrotomy must then be undertaken without delay, although if not already tried, an expedited and concurrent attempt can be made to place a supraglottic device.
Selection of the ideal airway device in patients with difficult airways (DA) or potentially difficult airways remains controversial, especially, for a novice anesthesia physician (NP) who must deviate from conventional direct laryngoscopy with a rigid laryngoscope following a failed intubation and employ one of the several alternative devices. The author determines and compares tracheal intubation success rates, times to success and complications of a novice physician using four alternative airway devices in 20 obese (BMI more than 27.5) patients who may be more difficult to intubate than normal weight patients.
Materials and Methods:
In this prospective randomized experimental study the author investigates a novice physician's use of the Bullard™, Fiberoptic™, Fastrach™ and Trachlight™ comparing reliability, rapidity and safety of orotracheal intubations. Following induction of anesthesia the NP was allowed up to a maximum of two attempts per device at oral intubation. Mean intubation times plus/minus SD, per cent success rates and postoperative complications were evaluated for each device.
The Fastrach™ was successful 100% of the time on the first attempt requiring a mean time of 55 seconds plus/minus 6.6. All intubations were unsuccessful following two attempts with the Fiberoptic™. A success rate of 20% (one of five) was achieved with the Trachlight™ on first attempt after 95 seconds. The Bullard™ was successful in 40 % (two of five) of the patients after a mean time 60 seconds plus/minus five, but was the only device to result in mild oral discomfort one day post operatively.
In the hands of a novice physician managing a difficult or potentially difficult airway, often encountered in obese patients, the Fastrach™ demonstrated the highest success rate.
Airway; difficult; physician
An expanding body of literature exists which describes the airway challenges and management options for lingual tonsillar hypertrophy (LTH). The use of retrograde intubation to secure a patient‘s airway in the setting of LTH has been previously unreported and should be considered early in the event of a cannot intubate, cannot ventilate scenario. A 55-year-old man, who had previously been described as an easy intubation, presented an unexpected cannot intubate, cannot ventilate scenario secondary to LTH. Various noninvasive airway maneuvers were attempted to restore ventilation without success. We describe the advantages of early use of wire-guided retrograde intubation as an alternative to a surgical airway for obtaining a secure airway in a patient with LTH, in whom noninvasive airway management maneuvers have failed. Multiple different noninvasive approaches to management of LTH have been previously described including the laryngeal tube, laryngeal mask airway, and fiberoptic bronchoscopy. Unfortunately, none of these noninvasive airway maneuvers successfully ventilated this patient and an invasive airway became necessary. Retrograde intubation is a less invasive alternative to the surgical airway with potentially less risk for complications. Retrograde intubation may be particularly effective in the setting of LTH as it may stent open an otherwise occluded airway and allow passage of an endotracheal tube. Skillful use of this technique should be considered early as a viable option in any case of unexpected difficult intubation due to LTH.
Lingual tonsillar hypertrophy; retrograde intubation; difficult intubation
In trauma patients intubated in a physician-led pre-hospital trauma service we prospectively examined the rate of misplaced tracheal tubes, the presence and nature of gross airway contamination, and the value of ‘quick look’ airway assessment to identify patients with subsequent difficult laryngoscopy.
Patients requiring pre-hospital intubation in a 16 month period were included. Intubation success rate, misplaced tracheal tube rate, Cormack and Lehane grade, and the presence and nature of gross airway contamination were recorded at laryngoscopy. Tube placement was verified with carbon dioxide detection and chest x-ray. After visual assessment physicians stated whether laryngoscopy was expected to be a straightforward or ‘difficult’. The assessment was compared to subsequent laryngoscopy grade.
400 patients had attempted intubation and 399 were successfully intubated. 42 were in cardiac arrest and intubated without drugs. There were no oesophageal or misplaced tracheal tubes. Gross airway contamination was reported in 177 of 400 patients (44%), of which ¾ was from the upper airway. Unconscious patients had higher contamination rates (57%) than conscious patients (34%) (p ≤ 0.0001). As a test of difficult intubation, the ‘quick look’ generated sensitivity 0.597 and specificity 0.763 (PPV and NPV were 0.336 and 0.904 respectively).
This study suggests that when physicians perform pre-hospital anaesthesia they have high intubation success rates and the use of ETCO2 monitoring reduces or eliminates undetected misplaced tracheal tubes. We found high rates of airway contamination; mostly blood from the upper airway. The ‘quick look’ airway assessment had some utility but is unreliable in isolation.
Tracheal intubation; Airway; Pre-hospital; Anaesthesia
Angioedema (AE) is edema of the skin, subcutaneous tissue and/or submucosal tissues, resulting from extravasation of intravascular fluid. Swelling of the supraglottic mucosa can lead to airway obstruction with consequent hypoxia, brain damage and death. To date, fiberoptic bronchoscope (FOB) intubation of the spontaneously breathing patient is the preferred method for an anticipated difficult intubation. However, other alternative devices can be utilized to intubate angioedema successfully.
Materials and Methods:
A retrospective chart review was performed over a three-year period (2008-2010) of all patients with angioedema that required airway intervention. We hypothesized that fiberoptic intubation would have a higher success rate for intubation attempts; however, would take longer to perform when compared to videolaryngoscopic (VL) intubation. Outcomes for FOB versus VL intubations were reviewed, along with alternative miscellaneous methods of tracheal intubation in the setting of angioedema.
Thirty-three patients were grouped, according to the chosen method of intubation into FOB (n=12), VL (n=11), and miscellaneous (n=10) groups. No significant difference was found in first intubation attempts or number of intubation attempts between the three groups. Duration of time to perform successful intubation revealed a significantly shorter intubation time (P<0.05) in the VL group (6.9±0.9 min) and miscellaneous group (9.1±2.0 min) than that of the FOB group (10.4±0.7 min).
This retrospective review of intubation methods showed that VL could be performed faster than FOB without an increase in adverse events.
Airway obstruction; angioedema; bronchoscope; bronchoscopy; intubation–laryngeal mask; videolaryngoscope