The intubating laryngeal mask airway in severe ankylosing spondylitis

PURPOSE: To evaluate the use of inhalational induction followed by intubation through the intubating laryngeal mask (ILM) for patients with severe ankylosing spondylitis undergoing elective surgery who prefer airway management under anesthesia. METHODS: Nine patients undergoing a total of 11 procedures were enrolled in the study. Fentanyl 2 microg*kg(-1), midazolam 0.035 mg*kg(-1) and sevoflurane in oxygen 100% were used for induction. The ILM was inserted when the end-tidal sevoflurane concentration reached 3%. After an effective airway was established, atracurium 0.5 mg*kg(-1) was given. A polyvinyl chloride tube in the reversed position using a blind technique was used to intubate the trachea. RESULTS: The ILM provided an effective airway on 11/11 occasions at the first attempt. Intubation was successful at the first attempt on 7/11 occasions, at the second attempt on 2/11 and at the third attempt in 1/11. Intubation failed in one patient. The mean (range) minimal oxygen saturation was 99.4% (97-100%). There were no problems with ILM removal. CONCLUSION: Inhalational induction followed by ILM insertion and blind intubation is a reasonable option in patients with severe ankylosing spondylitis undergoing elective surgery who prefer airway management under anesthesia.     

The intubating laryngeal mask airway compared with direct laryngoscopy

We have compared the ability of naive intubators to intubate the trachea using a laryngoscope and an intubating laryngeal mask airway (ILMA) after receiving basic training, in a randomized, prospective, crossover study in 60 patients. Ventilation of the lungs via the ILMA was also compared with ventilation with a face mask. There was no significant difference in successful intubation between the techniques (38 of 89 with the ILMA and 33 of 93 with direct laryngoscopy; ns). In patients in whom participants failed in their intubation attempts with the ILMA, investigators achieved success in 89% (16 of 18). Satisfactory ventilation was more common with the ILMA (50 of 51) than with the face mask (43 of 60) (P = 0.0001). A total of 98% (89 of 91) of ILMA were inserted successfully, with a mean insertion time of 19.6 s, and 78% (69/89) of these insertions were achieved in less than 26 s. The ILMA may be useful for emergency oxygenation and ventilation, but these results do not support its use for intubation by those not trained in advanced airway management and ILMA use.      

The intubating laryngeal mask airway in failed fibreoptic intubation

PURPOSE: Prediction of difficult tracheal intubation is not always reliable and management with fibreoptic intubation is not always successful. We describe two cases in which blind intubation through the intubating laryngeal mask airway (ILMA FasTrach) succeeded after fibreoptic intubation failed. CLINICAL FEATURES: The first patient, a 50 yr old man, was scheduled for elective craniotomy for intracerebral tumour. Difficulty with intubation was not anticipated. Manual ventilation was easily performed following induction of general anesthesia, but direct laryngoscopy revealed only the tip of the epiglottis. Intubation attempts with a styletted 8.0 mm endotracheal tube and with the fibreoptic bronchoscope were unsuccessful. A #5 FasTrach was inserted through which a flexible armored cuffed 8.0 mm silicone tube passed into the trachea at the first attempt. The second patient, a 43 yr old man, presented with limited mouth opening, swelling of the right submandibular gland that extended into the retropharynx and tracheal deviation to the left. He was scheduled for urgent tracheostomy. Attempted awake fibreoptic orotracheal intubation under topical anesthesia showed gross swelling of the pharyngeal tissues and only fleeting views of the vocal cords. A #4 FasTrach was easily inserted, a clear airway obtained and a cuffed 8.0 mm silicone tube passed into the trachea at the first attempt. CONCLUSION: The FasTrach may facilitate blind tracheal intubation when fibreoptic intubation is unsuccessful.     

The intubating laryngeal mask airway Fastrach for emergence after carotid endarterectomy

We determine the feasibility of using the intubating laryngeal mask airway Fastrach (ILM) as a ventilatory device during emergence from anesthesia after use as an airway intubator in patients undergoing carotid endarterectomy. Thirty-five patients (ASA 2-3, 53-84 yr) were studied. Induction was with midazolam/fentanyl/etomidate and maintenance was with sevoflurane 1-2% in O2 33-50% and N2O. Neuromuscular blockade was with cisatracurium. Tracheal intubation was with a flexible lightwand via the ILM. After successful intubation, the ILM remained in the pharynx, but with the cuff deflated. After surgery, but before anesthesia was discontinued, baseline cardiovascular variables were recorded. The ILM cuff was then reinflated, the tracheal tube removed, the anesthesia breathing system connected to the ILM and anesthesia discontinued. Any changes in the cardiovascular variables greater than +/- 20% baseline values were noted from cuff reinflation to 1 minute after ILM removal. Any adverse respiratory (laryngospasm, coughing, gagging, stridor, SpO2 <94%, end-tidal carbon dioxide >45 mmHg, regurgitation/aspiration) or electrocardiographic (ST segment or rhythm changes) events were also noted. Patients were questioned about postoperative sore throat at 2 and 24 hr. ILM insertion and intubation through the ILM were successful in all patients. Adequate ventilation was achieved in all patients before intubation and after extubation. The mean (range) time taken from cuff reinflation to ILM removal was 9 (5-21) min. The rate pressure product remained within +/- 20% baseline values in all patients. There were no adverse respiratory or electrocardiographic events. There were no adverse neurological events. The surgical field was satisfactory. Postoperative sore throat occurred in 14% at 2 hr and 0% at 24 hr. We conclude that the ILM can be used as a ventilatory device for emergence from anesthesia after use as an airway intubator for carotid endarterectomy.     

Conventional tracheal tubes for intubation through the intubating laryngeal mask airway

The laryngeal mask airway (LMA)-Fastrach silicone wire-reinforced tracheal tube (FTST) was specially designed for tracheal intubation through the intubating LMA (ILMA). However, conventional tracheal tubes have been successfully used to accomplish tracheal intubation. We designed this study to evaluate the success rate of blind tracheal intubation through the ILMA by using the FTST, the Rusch polyvinyl chloride tube (PVCT), and the Rusch latex armored tube (LAT). One-hundred-fifty healthy adults of ASA physical status I and II who were undergoing elective surgery under general anesthesia were randomly allocated into three groups. FTST (n=50), prewarmed PVCT (n=50), and LAT (n=50) were used for tracheal intubation. Ease of tracheal intubation was assessed by the time taken, the number of attempts, and the number of maneuvers required for success. In addition, numbers of failed intubation attempts and times taken for ILMA removal were also recorded. After surgery, the incidence of trauma, sore throat, and hoarseness was noted. Significantly more frequent success in tracheal intubation was achieved with the PVCT and FTST (96%) compared with the LAT (82%) (P <0.05). Tracheal intubation on the first attempt was similar with the PVCT and FTST (86%) and was significantly more frequent than with the LAT (52%) (P <0.05). Esophageal placement was significantly more frequent with the LAT (29.7%) when compared with the PVCT and FTST (1.8% and 7.4%, respectively) (P <0.05). The authors conclude that a prewarmed PVCT can be used as successfully as the FTST for blind tracheal intubation through the ILMA, whereas the LAT is associated with more frequent failure and esophageal intubation.     

The intubating laryngeal mask airway with and without fiberoptic guidance

We conducted this feasibility study using the intubating laryngeal mask airway (ILMA) and a polyvinyl chloride tracheal tube to compare success rates, hemodynamic effects, and postoperative morbidity with two methods of tracheal intubation. After ethics approval and informed consent, 90 healthy ASA physical status I or II women with normal airways were enrolled in the randomized, controlled study. After a standardized inhaled anesthesia induction protocol, tracheal intubations using ILMA with fiberoptic guidance (ILMA-FOB) and ILMA inserted blindly without fiberoptic guidance (ILMA-Blind) were compared with the control group of direct laryngoscopy (laryngoscopy group). All 90 patients were successfully ventilated. For tracheal intubation, success rates were equal in all three groups (97%). Total intubation times were longer for the ILMA-FOB group (77 s versus 48.5 s for laryngoscopy and 53.5 s for ILMA-Blind). The laryngoscopy group had a larger increase in mean arterial blood pressure to tracheal intubation. There were no differences in postoperative sore throat or hoarseness among the groups. In conclusion, success rates are equally high for tracheal intubation using ILMA-Blind and ILMA-FOB techniques in women with normal airways. IMPLICATIONS: The intubating laryngeal mask airway (ILMA) can be used as a primary airway for oxygenation and ventilation. Both methods of tracheal intubation using the ILMA were equally successful. Postoperative morbidity in the ILMA groups was similar to that in the laryngoscopy group. For women with normal airways, both the ILMA inserted blindly and the ILMA with fiberoptic guidance are suitable alternatives to laryngoscopy for tracheal intubation.     

Removal of the connector on the laryngeal mask airway provides a useful alternative to the intubating laryngeal mask

PURPOSE: We describe two cases in which fiberoptic intubation through the standard laryngeal mask airway (LMA) was successful with large-bore tracheal tubes (TTs) when an intubating LMA (ILMA) could not be used. CLINICAL FEATURES: Patient # 1, with obstructive sleep apnea, underwent elective surgical repair. His mouth opening was just under 25 mm, but difficult intubation was not anticipated. We induced general anesthesia, easily ventilated the patient by mask, and established neuromuscular blockade. Direct laryngoscopy and attempts to insert either a #5 or a #4 ILMA into the mouth failed. A standard #4 LMA, with the connector removed, was inserted, through which a 7.0 mm nasal RAE TT, fiberoptically guided, passed into the trachea at the first attempt. Patient #2, with a loosened implant after left hip arthroplasty, underwent revision prosthesis. Her neck movement was limited. We thus planned awake securing of the airway, but the patient refused. We induced anesthesia and established bag-mask-valve ventilation. The limited neck movement prevented direct laryngoscopy. Visualizing the laryngeal inlet with the fiberoptic bronchoscope (FOB) proved impossible as bloody secretions obscured the FOB's tip. Ventilation by mask was easy. As an ILMA was not available, we removed a #5 LMAs connector and passed an 8.0 mm nasal RAE TT through the LMA. Fiberoptic-guided intubation was easy. In both cases, the remainder of the intraoperative course was uneventful. CONCLUSION: A standard LMA whose connector has been removed to allow passage of TTs of >6.0 mm internal diameter may be substituted for the ILMA when necessary.     

Manikin study of fibreoptic‐guided intubation through the classic laryngeal mask airway with the Aintree intubating catheter vs the intubating laryngeal mask airway in the simulated difficult airway*

In this randomised crossover manikin study of simulated difficult intubation, 26 anaesthetists attempted to intubate the trachea using two fibreoptic‐guided techniques: via a classic laryngeal mask airway using an Aintree intubating catheter and via an intubating laryngeal mask airway using its tracheal tube. Successful intubation was the primary endpoint, which was completed successfully in all 26 cases using the former technique, and in 5 of 26 cases using the latter (p < 0.0001). The former technique also proved quicker to reach the vocal cords with the fibrescope (median (IQR [range])) time 18 (14–20 [8–44]) s vs 110 (70–114 [30–118]) s, respectively; p = 0.008); and to first ventilation (93 (74–109 [52–135]) s vs 135 (79–158 [70–160]) s, respectively; p = 0.0038)]. We conclude that in simulated difficult intubation, fibreoptic intubation appears easier to achieve using a classic laryngeal mask airway and an Aintree intubating catheter than through an intubating laryngeal mask airway.     

Use of intubating laryngeal mask airway for three patients with difficult intubation

We used intubating laryngeal mask airway (ILM) for three patients with difficult intubation, and tracheal intubation was successfully performed through the ILM in all three cases. Difficult intubation in the first case was caused by direct invasion of malignant lymphoma into the right maxillary sinus leading to restricted mouth opening. Neck stiffness due to invasion of metastatic cancer into the cervical spine in the second case and facial trauma caused by traffic accident in the third case gave rise to the difficult intubation. Insertion of the ILM was successfully performed in all the patients following induction of general anesthesia, and the ventilation through the ILM was possible without any difficulties. Subsequently, all patients were intubated through the ILM successfully. We realized that the ILM is useful and should be prepared on the induction of anesthesia in patients suspected of difficult intubation.     

The intubating laryngeal mask airway: rocuronium improves endotracheal intubating conditions and success rate

STUDY OBJECTIVE: To assess intubating conditions without neuromuscular blocking drugs, to determine the relation between the dose of rocuronium and the probability of achieving excellent or at least good (good or excellent) intubating conditions with the intubating laryngeal mask airway (ILMA), and finally, to determine the relationship between rocuronium use and the success rate of endotracheal intubation. DESIGN: Prospective, randomized, double-blinded, placebo-controlled study. SETTING: University-affiliated medical center. PATIENTS: Sixty American Society of Anesthesiologists physical status I and II patients undergoing elective surgery. INTERVENTIONS: Anesthesia was induced with propofol 2.5 mg/kg and fentanyl 1 microg/kg. One minute after loss of consciousness, patients received rocuronium 0.2 mg/kg or saline. In the rocuronium group, if intubating conditions were scored as poor, rocuronium dose in the next patient was increased by 0.05 mg/kg. If intubating conditions were scored as good, no change was made, but if conditions were scored as excellent, the dose was decreased by 0.05 mg/kg. One minute after rocuronium or saline administration, an ILMA was used to intubate the trachea. If intubation was unsuccessful, a second attempt was made using the ILMA. MEASUREMENTS: We recorded intubating conditions and the success rate of tracheal intubation. MAIN RESULTS: Without rocuronium, the probability of achieving at least good intubating conditions with the ILMA was 30%. A rocuronium dose of 0.2 mg/kg resulted in a probability of 80% to achieve at least good intubating conditions. Rocuronium significantly increased the success rate of the second intubation attempt. CONCLUSION: To achieve good or excellent intubating conditions with the ILMA, a rocuronium dose lower than the standard intubating dose of 0.6 mg/kg can be used. Neuromuscular blockade increases the success rate of intubation if a second attempt is necessary.