A Comparative Easiness of Blind Orotracheal Intubation Using Intubating Lacryngeal Mask Airway with Two Different Head Positions / 대한마취과학회지

BACKGROUND: The position for tracheal intubation using direct laryngoscopy is extension of the head with flexion of the neck, the classical 'sniffing position'. If necessary, an extra pillow can be used to keep the neck flexed. By adopting this position the oral, pharyngeal, and laryngeal axes is a almost straight line to facilitate tracheal intubation. Also, this position is ideal for conventional laryngeal mask airway (LMA) insertion. However, insertion of intubating laryngeal mask airway (ILM) and intubation through ILM may be achieved from any position relative to the patient's head. As recommended by the manufacturer, when possible a pillow should be placed under the head to achieve a neutral position. The purpose of this study was therefore to compare the easiness of intubation through ILM without support and with the patient's head supported by a pillow. METHODS: After acquiring informed consent, 80 ASA grade 1 or 2 patients undergoing general anesthesia for elective surgical procedures who normally required tracheal intubation were randomized into two groups. In group 1 (n = 40), insertion of ILM and intubation was conducted with the head supported by a pillow, while there was no support in group 2 (n = 40). The patients were induced and relaxed with an IV injection of thiopental sodium, fentanyl-ketamine-midazolam mixture and vecuronium. When adequate level of anesthesia was achieved, the ILM was inserted. After adequate ventilation was confirmed, a blind tracheal intubation through the ILM was attempted. Then we recorded success rate, insertion time, intubation time and adjusting maneuvers. RESULTS: The ILM was successfully inserted on the first attempt in 79/80 patients, but 1 patient of group 1 failed to be adequately ventilated. The mean time for ILM insertion of group 2 was shorter than that of group 1. The success rate of tracheal intubation was 37(95%) in group 1 and 40 (100%) in group 2. In group 1, 30 (81%) patients were successfully intubated on the first attempt, 1 (3%) patient on the second attempt, and 6(16%) patients on the third attempt; in group 2, 35 (87%) patients on the first attempt, and 5 (13%) patients on the third attempt. There was no significant diffrence of mean time taken for endotracheal intubation through ILM between group 1 (105.1 sec) and group 2 (88.1 sec). CONCLUSIONS: The authors conclude that ILM insertion is significantly easier with the patient's head not supported by a pillow compared with the patient's head supported by a pillow and there is no difference in ease of intubation through ILM by the patient's head position.

A Comparison of Two Types of Tracheal Tube for Use in Intubating Laryngeal Mask Airway Assisted Blind Orotracheal Intubation / 대한마취과학회지

BACKGROUND: The conventional laryngeal mask airway (LMA) has been used to facilitate blind tracheal intubation in numerous situations where laryngoscopy and conventional intubation has been difficult, but it has the disadvantage that its airway tube is too long and narrow for intubation. The intubating laryngeal mask airway (ILM) has been specifically designed to increase the success rate of blind intubation. A specially constructed ILM tracheal tube is available for use with the ILM, But this tube is in short supply and expensive. Thus, this study was performed to compare the success rate and time of blind intubation through ILM with reinforced tracheal tube or specially-designed tracheal tube, and to assess the use of reinforced tracheal tube as a substitute for specially-designed tracheal tube. METHODS: After acquiring informed consent, 60 ASA grade 1 or 2 patients undergoing anesthesia for elective surgical procedures who normally required tracheal intubation were randomized into two groups. In group 1 (n = 30), the patients were intubated with a specially-designed tracheal tube through ILM. In group 2 (n = 30), reinforced tracheal tubes were used. The patients were induced and relaxed with an iv injection of thiopental sodium, fentanyl-ketamine-midazolam mixture and vecuronium. When an adequate level of anesthesia was achieved, the ILM was inserted. After adequate ventilation was confirmed, blind tracheal intubation with either of the two types of tracheal tubes through the ILM was attempted. Then we recorded success rate, intubation time and adjusting maneuvers. RESULTS: The ILM was successfully inserted at first attempt in 59/60 (98%) patients, but in 1 patient, adequate ventilation was not acheived. The success rate of tracheal intubation was 27 (93%) in group 1 and 28 (93%) in group 2. In group 1, 21 (72%) patients were successfully intubated on the first attempt, 1 (4%) patient on the second attempt, and 5 (17%) patients on the third attempt. In group 2, 20 (67%) patients were successfully intubated on the first attempt, 2 (6%) patients on the second attempt, and 6 (20%) patients on the third attempt. The mean time taken for intubation was 116.9 sec in group 1 and 122.3 sec in group 2. CONCLUSIONS: The authors conclude that the reinforced tracheal tube can be substitute for a specially- designed tracheal tube.

Comparison of Train-of-four Response between Adductor Pollicis and Orbicularis Oculi to Determine the Optimal Time for Endotracheal Intubation after Vecuronium Administration / 대한마취과학회지

BACKGROUND: Ideal condition of endotracheal intubation after administration of non-depolarizing muscle relaxants like vecuronium is the time when the diaphragm and upper airway muscles are completely relaxed. But these muscles are difficult to determine the degree of relaxation. Neuromuscular response of these muscles are similar to that of orbicularis oculi (OO), but adductor pollicis (AP) is different. However, it is sometimes difficult to monitor OO response. The purpose of this study was to monitor the upper airway muscle relaxation using AP other than OO. METHODS: Fourty-four adult patients of ASA class 1 schaduled for elective surgery under general anesthesia were examined. Anesthesia was induced with fentanyl 2 mcg/kg, and 2 minutes later followed by thiopental sodium 5 mg/kg. After supramaximal stimulation for control twitch height, vecuronium 0.1 mg/kg was intravenously injected and applied continuous train-of-four (TOF) facial nerve stimuli. The TOF response of OO was closely observed with examiner's naked eyes. When complete relaxation of OO achieved, TOF ratio of AP and the time after vecuronium injection were recorded. Thereafter, tracheal intubation was performed and the intubating condition scores was recorded. Ulnar nerve stimuli were continuously applied until complete relaxation of AP was achieved. The time of complete relaxation of AP after vecuronium injection was also recorded. RESULTS: The onset time of complete relaxation was significantly faster in OO (181.3+/- 47.4 secs) as compared with that of AP (265.0+/-67.8 secs). The average TOF ratio of AP was 47.3+/-17.2% and the condition of intubation performed after complete relaxation of OO was satisfied. CONCLUSION: The optimal time for endotracheal intubation was about 3 min after vecuronium 0.1 mg/kg injection, when TOF ratio of AP was about 50%.

Endotracheal Intubation through the Intubating LMA / 대한마취과학회지

BACKGROUND: The fundamental responsibility of an anesthesiologist is to maintain adequate ventilation and to supply oxygen in the face of unexpected difficulties with tracheal intubation. The laryngeal mask airway (LMA) has been used as a ventilatory device familiarly for routine or difficult intubation but it has been hard to intubate with it the larger than 6 mm internal diameter (ID) endotracheal tube (ET). The intubating LMA is a new prototype of the LMA; it is partey composed of an anatomically curved rigid airway tube of ID 13 mm for larger ET tube insertion (such as ID 9.0 mm) into a 15 mm connector at its outer end which is fixed permanently to a laryngeal mask. This study was performed to evaluate the technique and facility of the intubating LMA as an apparatus for endotracheal intubation when used by an inexperienced anesthesiologist. METHODS: With informed consent, 43 patients of ASA physical status I or II were selected. Either lubricated polyvinyl chloride or an armored wire tube of ID 7.0 or 7.5 mm was intubated through the No. 4 or 5 intubating LMA. During this procedure, we observed the technical method and success rate, and recorded systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate (HR) changes. 24 hours after each operation, we observed subjective symptoms such as sore throat, hoarseness, and difficult in swallowing. RESULTS: The success rate of intubating LMA insertion was as follows: 33 (77%) patients were successed on first attempt, 6 (14%) patients on second attempt, 4 (9%) patients on third attempt. The insertion of the intubating LMA was carried out facilely without another maneuver such as neck extension or tongue expulsion. The success rate of tracheal intubation was 86.1%. In 32 (74.5%) patients there was easy intubation, but 5 (11.6%) patients required more adjustment and the failure rate with them was 6 (13.9%). SBP, DBP were only increased by endotracheal intubation through the intubating LMA, but HR was significantly increased during both insertion and intubation (p < 0.05). Postoperative sore throat was complained of in 11 patients; hoarseness in 1 patient. CONCLUSIONS: Insertion of the intubating LMA is facile due to the absence of need for the maneuvers of neck motion or tongue expulsion. The intubating technique through the intubating LMA is a relatively rapid and easy method, but it requires technical experience which in some cases is lacking in inexperienced anesthesiologists.

Endotracheal Intubation through the Intubating LMA / 대한마취과학회지

BACKGROUND: The fundamental responsibility of an anesthesiologist is to maintain adequate ventilation and to supply oxygen in the face of unexpected difficulties with tracheal intubation. The laryngeal mask airway (LMA) has been used as a ventilatory device familiarly for routine or difficult intubation but it has been hard to intubate with it the larger than 6 mm internal diameter (ID) endotracheal tube (ET). The intubating LMA is a new prototype of the LMA; it is partey composed of an anatomically curved rigid airway tube of ID 13 mm for larger ET tube insertion (such as ID 9.0 mm) into a 15 mm connector at its outer end which is fixed permanently to a laryngeal mask. This study was performed to evaluate the technique and facility of the intubating LMA as an apparatus for endotracheal intubation when used by an inexperienced anesthesiologist. METHODS: With informed consent, 43 patients of ASA physical status I or II were selected. Either lubricated polyvinyl chloride or an armored wire tube of ID 7.0 or 7.5 mm was intubated through the No. 4 or 5 intubating LMA. During this procedure, we observed the technical method and success rate, and recorded systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate (HR) changes. 24 hours after each operation, we observed subjective symptoms such as sore throat, hoarseness, and difficult in swallowing. RESULTS: The success rate of intubating LMA insertion was as follows: 33 (77%) patients were successed on first attempt, 6 (14%) patients on second attempt, 4 (9%) patients on third attempt. The insertion of the intubating LMA was carried out facilely without another maneuver such as neck extension or tongue expulsion. The success rate of tracheal intubation was 86.1%. In 32 (74.5%) patients there was easy intubation, but 5 (11.6%) patients required more adjustment and the failure rate with them was 6 (13.9%). SBP, DBP were only increased by endotracheal intubation through the intubating LMA, but HR was significantly increased during both insertion and intubation (p < 0.05). Postoperative sore throat was complained of in 11 patients; hoarseness in 1 patient. CONCLUSIONS: Insertion of the intubating LMA is facile due to the absence of need for the maneuvers of neck motion or tongue expulsion. The intubating technique through the intubating LMA is a relatively rapid and easy method, but it requires technical experience which in some cases is lacking in inexperienced anesthesiologists.

Intubating Laryngeal Mask Airway in Difficult Intubation: A case report / 대한마취과학회지

The incidence of difficult laryngoscopy or intubation varies from 1.5% to 13%, and failed intubation has been identified as one of the anesthesia-related causes of death or permanent brain damage. The Intubating Laryngeal Mask Airway (ILMA) is a new modified laryngeal mask with the capability for guided tracheal intubation while maintaining ventilation. The ILMA was designed by Brain to improve blind endotracheal intubation through a laryngeal mask. We report the successful use of this device in two patients with difficult airway during induction of general anesthesia.

Intubating Laryngeal Mask Airway in Difficult Intubation: A case report / 대한마취과학회지

The incidence of difficult laryngoscopy or intubation varies from 1.5% to 13%, and failed intubation has been identified as one of the anesthesia-related causes of death or permanent brain damage. The Intubating Laryngeal Mask Airway (ILMA) is a new modified laryngeal mask with the capability for guided tracheal intubation while maintaining ventilation. The ILMA was designed by Brain to improve blind endotracheal intubation through a laryngeal mask. We report the successful use of this device in two patients with difficult airway during induction of general anesthesia.

Prediction of Depth of Left-sided Double Lumen Tube Insertion Using Preoperative Chest X-ray / 대한마취과학회지

INTRODUCTION: Accurate placement of double-lumen endobronchial tube (DLT) is essential for optimal gas exchange and collapse of nondependent lung during one-lung anesthesia. The goal of this study was to determine if measurement of tracheal length from the preoperative chest X-ray can be used for the prediction of adequate length of left-sided DLT insertion. METHODS: 25 patients scheduled for elective thoracotomy under one-lung anesthesia were studied. After measurement of tracheal length from preoperative chest X-ray and of length from incisor to vocal cord during intubation, the patient was intubated with left-sided DLT to the depth of predetermined length from incisor to carina. The tube position was evaluated with fiberoptic bronchocsope. RESULTS: In 22 patients (88%) the DLTs were positioned satisfactorily, and in three patients it was required to reposition DLT. CONCLUSIONS: This technique may be useful for accurate placement of DLT for the one-lung anesthesia.