Clinical Assessment of a Plastic Optical Fiber Stylet for Human Tracheal Intubation

Background: The authors compared the performance of a prototype intubation aid that incorporated plastic illumination and image guides into a stylet with fiberoptic bronchoscopy and direct laryngoscopy for tracheal intubation by novice users.

Methods: In a randomized, nonblinded design, patients were assigned to direct laryngoscopy, fiberoptic bronchoscopy, or imaging stylet intubation groups. The quality of laryngeal view and ease with which it was attained for each intubation was graded by the laryngoscopist. Time to intubation was measured in 1-min increments. A sore-throat severity grade was obtained after operation.

Results: There were no differences in demographic, physical examination, or surgical course characteristics among the groups. The laryngoscope produced an adequate laryngeal view more easily than did the imaging stylet or bronchoscope (P = 0.001) but caused the highest incidence of postoperative sore throat (P < 0.05). Although the time to intubation for direct laryngoscopy was shorter than for imaging stylet, which was shorter than fiberoptic bronchoscopy (P < 0.05), the quality of laryngeal view with the imaging stylet was inferior to both direct laryngoscopy and fiberoptic bronchoscopy techniques (P < 0.05).     

预期困难气道患者喉罩辅助纤维支气管镜引导气管插管的研究

目的 探讨在预期困难气道患者中采用喉罩辅助纤维支气管镜(fiberoptic bronchoscope,FOB)引导气管插管的应用价值. 方法 择期经口气管插管全身麻醉手术预测困难气道患者24例,ASA Ⅰ或Ⅱ级,入选患者达到以下1种或几种条件为预期困难气道:1.5 cm＜张口度＜3 cm,甲颏间距＜6 cm,头颈活动度＜80°,Mallampati分级Ⅲ、Ⅳ级.采用随机数字表法分为喉罩辅助FOB组(F组)和直接喉镜组(L组),每组12例.F组采用喉罩辅助FOB引导下气管插管;L组在直接喉镜暴露下经口气管插管,3次试插未成功者改行F组方法试插.记录两组患者的气道评估情况、气管插管前(基础值)和插管后3 min的MAP和HR、成功插管的次数及术后的并发症的发生情况. 结果 插管前两组气道评估差异无统计学意义(P＞0.05).与插管前相比,L组患者插管后MAP和HR显著增加,差异有统计学意义(P＜0.05).两组插管后的MAP和HR比较,差异有统计学意义(P＜0.05).F组气管插管一次成功率为75％,3次以内插管合计总成功率为100％;L组气管插管一次成功率为25％,3次以内插管合计总成功率为50％;6例L组患者直接喉镜3次插管不成功后改为喉罩辅助FOB插管,2例1次成功,4例2次成功;F组一次插管成功率和3次插管总成功率均显著高于L组,两组比较差异有统计学意义(P＜0.05).与L组插管时间(161±26)s比较,F组插管时间(81±9)s明显缩短,差异有统计学意义(P＜0.05).F组有2例术后轻度咽喉疼痛,L组有6例术后咽喉疼痛明显和轻度声嘶、2例轻度咽痛. 结论 对术前预期为困难气道的患者采用喉罩辅助FOB引导气管插管可显著提高插管的成功率,降低直接喉镜反复试插引起的术后并发症,具有一定的临床应用价值.     

改良普通喉罩辅助纤维支气管镜气管插管在困难气道患者中的应用

目的观察改良普通喉罩辅助纤维支气管镜(fiberoptic bronchoscope,FOB)气管插管在困难气道患者中的应用效果。方法选择经熟练麻醉医师使用直接喉镜插管2次失败的择期全麻手术患者40例,男21例,女19例,年龄30~55岁,ASAⅠ或Ⅱ级,随机分为两组,每组20例。研究组(LMA-FOB组)将普通喉罩进行改良(剪开喉罩出口栅栏分隔处,剪短通气管),辅助FOB气管插管;对照组(FOB组)经口垫直接使用FOB气管插管。观察咽部解剖结构显露分级,记录一次插管成功率及插管时间,记录拔除喉罩带血和术后咽喉部疼痛、声音嘶哑等不良反应的发生情况。结果与FOB组比较,LMA-FOB组咽部解剖结构显露分级明显提高(Ⅰ/Ⅱ/Ⅲ/Ⅳ级:15/4/1/0vs.8/4/5/3,P0.05),一次插管成功率明显提高(90%vs.60%,P0.05),插管时间明显缩短[(75±20)s vs.(105±25)s,P0.05)]。术后LMA-FOB组仅1例喉罩带血,1例咽部轻微疼痛。结论对可能存在困难气道的患者,采用改良普通喉罩辅助纤维支气管镜引导气管插管可明显提高咽部解剖结构显露分级,提高一次插管成功率,缩短插管时间,术后无明显不良反应,是一种比较安全有效的方法,有一定的临床应用价值。     

颈椎手术患者i-gel喉罩辅助纤维支气管镜引导气管插管的效果

目的 评价颈椎手术患者i-gel喉罩辅助纤维支气管镜引导气管插管的效果.方法 择期全麻气管插管的颈椎手术患者40例,ASA分级Ⅰ或Ⅱ级,性别不限,年龄36～62岁,体重57～78 kg,身高165～177 cm,Mallampati分级Ⅰ～Ⅲ级,随机分为2组(n=20):口咽通气道辅助FOB引导气管插管组(O组)和i-gel喉罩辅助FOB引导气管插管组(I组).麻醉诱导后,进行气管插管.记录气管插管时间、纤维支气管镜咽部解剖结构显露分级、气管插管置人情况;记录气管插管期间高血压、心动过速和低氧血症的发生情况;记录拔除喉罩带血和术后咽喉部不良反应的发生情况.结果 i-gel喉罩均1次置入成功,置入时间为(10±3)s,两组气管插管成功率均为100%;与O组比较,I组气管插管时间缩短,1次气管插管成功率升高,纤维支气管镜咽部解剖结构显露分级升高(P＜0.05).两组气管插管期间血液动力学稳定,均未发生高血压和心动过速和低氧血症,I组仅1例喉罩粘血,两组均未见其他不良反应发生.结论 颈椎手术患者i-gel喉罩辅助纤维支气管镜引导气管插管不仅可确保有效的通气,而且可提高引导气管插管成功机率,缩短操作时间.     

A comparison of bullard laryngoscope and intubating laryngeal mask using fiberoptic guidance for tracheal intubation

The purpose of this study is to compare the success rate of tracheal intubation, intubation time and laryngoscopic view of the larynx by Bullard laryngoscope or by intubating laryngeal mask using fiberoptic guidance in 50 patients. Following a standardized induction protocol, conventional laryngoscopic view by Macintosh's laryngoscope was obtained and classified by Cormack's grades. We measured the times from incertion of laryngoscopy or laryngeal mask until obtaining the best view of the larynx and until tracheal intubation. A best view by Bullard laryngoscopy or by fiberoscopy through the laryngeal mask was classified by Cormack's grades. The success rate of tracheal intubation was higher by Bullard laryngoscopy than by intubating laryngeal mask. The durations of laryngoscopy and tracheal intubation were significantly shorter and Cormack's grades were significantly lower by Bullard laryngoscopy than by laryngeal mask and fiberscopy. These results demonstrate that tracheal intubation by Bullard laryngoscope is faster and more successful compared with intubating laryngeal mask using fiberoptic guidance.     

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.     

Management of airway in patients with laryngeal tumors

STUDY OBJECTIVE: To describe our systematic approach to securing the airway in patients with laryngeal tumors, developed over a 10-year period. DESIGN: Retrospective analysis. SETTING: University-affiliated veterans administration medical center. PATIENTS: Eight hundred one patients presenting for laryngeal tumor surgery in a 10-year period, 285 of whom underwent tracheostomy (25 with local anesthesia and 260 with general anesthesia). INTERVENTIONS: Preoperative examination, including history, physical examination, computed axial tomography and/or magnetic resonance imaging, and ear, nose, and throat surgeons' evaluation via indirect laryngoscopy or fiberoptic bronchoscopy were performed before the anesthesiologist's interventions. Local (topical) anesthesia and mild sedation were used for laryngeal evaluation with fiberoptic bronchoscopy. Tumor grade was then established, which determined how the airway would be secured: general anesthesia induction, receive topical anesthesia for awake, direct laryngoscopy, and tracheal intubation, or undergo tracheostomy with local anesthesia. MEASUREMENTS AND MAIN RESULTS: When the airway was secured, surgeons performed the biopsy, (any) tumor debulking, laser excision, or tracheostomy to establish both the airway and the diagnosis. Pulmonary function, including flow-volume loops and blood gas analysis were also useful in evaluating the degree of obstruction and gas exchange. In the event of respiratory distress, tracheostomy was performed after tracheal intubation or with local anesthesia, followed by direct laryngoscopy and biopsy. Depending on the diagnosis, further surgery and radiation treatment were planned next. CONCLUSIONS: With these guidelines, we have reduced the frequency of emergencies because of a lost airway, bleeding, or dislodging of tumor.     

Hemodynamic and catecholamine response to tracheal intubation: direct laryngoscopy compared with fiberoptic intubation

STUDY OBJECTIVE: To compare the stress response following tracheal intubation using direct laryngoscopy to that using fiberoptic bronchoscopy technique. DESIGN: Randomized, prospective study. SETTING: Operating rooms in a teaching hospital. PATIENTS: 51 ASA physical status I and II patients who were scheduled for an elective surgery with general anesthesia. INTERVENTIONS: Patients were randomly assigned to receive either direct laryngoscopy or fiberoptic orotracheal intubation, as part of general anesthesia. A uniform protocol of anesthetic medications was used. MEASUREMENTS: Blood pressure and heart rate were measured before induction, before endotracheal intubation, and 1, 2, 3, and 5 minutes afterwards. Catecholamine (epinephrine and norepinephrine) blood samples were drawn before the induction, and 1 and 5 minutes after intubation. MAIN RESULTS: Duration of intubation was shorter in the direct laryngoscopy group (16.9 (16.9 +/- 7.0 sec, range 8 to 40) compared with the fiberoptic intubation group (55.0 +/- 22.5 sec, range 29 to 120), p < 0.0,001. In both groups, blood pressure and heart rate were significantly increased at 1, 2, and 3 minutes after intubation, but there was no significant difference between the two study groups. Catecholamine levels did not increase after intubation and did not correlate with the hemodynamic changes. CONCLUSIONS: The use of either direct laryngoscopy or fiberoptic bronchoscopy produces a comparable stress response to tracheal intubation. Catecholamine levels do not correlate with the hemodynamic changes.     

difficult airway management: comparison of the bullard laryngoscope with the video-optical intubation stylet

PURPOSE: To evaluate, whether the video-optical intubation stylet (VOIS) was more successful for difficult tracheal intubation than the Bullard laryngoscope (BL). METHODS: An intubation mannequin head was modified so that, using a Macintosh blade size 3, only the epiglottis was visible at direct laryngoscopy, representing a grade III laryngoscopic view. Forty anesthesiologists attempted tracheal intubation using each technique. Tracheal intubation with the Bullard laryngoscope was performed using the attached non-malleable intubating stylet preloaded with an endotracheal tube. The video-optical intubation stylet inserted into an endotracheal tube was used with direct laryngoscopy. During conventional laryngoscopy, the video-view from the stylet tip allowed the tracheal tube to be guided behind the epiglottis into the trachea. Ten attempts with each technique were performed by each anesthesiologist in randomized order. Intubation time, and failed intubation (> 60 sec/esophageal intubation) were recorded. The operators assessed the degree of difficulty of each method using a Likert-scale. RESULTS: Mean intubation time (19.2+/-4.5 sec for the BL and 18.8+/-4.6 sec for the VOIS) was almost the identical. The video-optical intubation stylet was associated with fewer failed intubations (8 vs. 41; P<0.005) and had a lower degree of difficulty (1.7+/-0.65 for the VOIS and 2.6+/-0.74 for the BL; P<0.0001). No correlation was found between the anesthesiologist's experience and mean intubation time, estimated degree of difficulty or number of unsuccessful intubation. CONCLUSION: The video-optical intubation stylet was a more effective and simpler intubation device to facilitate difficult tracheal intubation than the Bullard laryngoscope.     

控制气管导管套囊压力对全麻手术患者气管插管相关性并发症的影响:前瞻性、多中心、随机、双盲研究

目的 探讨控制气管导管套囊压力对全麻手术患者气管插管相关性并发症的影响.方法 本研究为前瞻性、多中心、随机、双盲研究.择期拟行全麻手术患者509例,ASA分级Ⅰ或Ⅱ级,年龄11～89岁,体重35～92kg,性别不限,随机分为2组:对照组(C组)和套囊压力测定组(CPM组),记录手术时间和带管时间.各组随机选取20例带管时间120～180 min的患者,于拔除气管导管时行纤维支气管镜检查.拔除气管导管后24 h内随访咳嗽及痰中带血等气管插管相关性并发症的发生情况.结果 两组患者年龄、性别构成比、手术时间及带管时间差异无统计学意义(P＞0.05).与C组比较,CPM组患者咽喉痛及痰中带血的发生率降低(P＜0.05);随带管时间延长,C组咽喉痛及痰中带血的发生率均升高,CPM组仅咽喉痛的发生率升高(P＜0.01).纤维支气管镜检查可见气管粘膜不同程度损伤,C组较CPM组严重.结论 控制气管导管套囊压力有助于减少全麻手术患者术后气管插管相关性并发症的发生.     

The use of bronchial fibroscopy for difficult intubations in maxillofacial surgery

BACKGROUND: Evaluation of difficulties and modalities of tracheal intubation in maxillofacial surgery. METHODS: Design: retrospective study. Setting: maxillofacial operation room. 2152 patients who underwent elective maxillofacial surgery during a five-year time, from 1994 to 1998. Indications and alternative modalities of tracheal intubation through fiberoptic bronchoscope in eight patients (0.37%) with preoperatively evaluated difficult intubation due to temporomandibular ankylosis (3 patients), burns sequelae (1 patient), craniofacial congenital malformations (2 patients), unstables fractures of the cervical spine (2 patients), are discussed. Fiberoptic bronchoscope was used through nasotracheal route under topical nasal and laryngeal anaesthesia, combined with appropriate benzoanalgesia, in order to maintain spontaneous breathing. Proper positioning of tracheal tube was directly checked by fiberoptic bronchoscope, through visualization of the tracheal carina. RESULTS: In seven patients tracheal intubation was easily performed without complications in less than 20 minutes. In the eight patients the time spent was 35 minutes, due to important nasal bleeding, which caused a change of the nostril. CONCLUSION: Among the alternative methods of elective tracheal intubation, previously evaluated as difficult or impossible using conventional laryngoscopy, the use of fiberoptic bronchoscope seems to be safest and easiest to use, although not the cheapest.     

Sore throat and hoarseness after fiberoptic nasotracheal intubation

Fiberoptic nasotracheal intubation is frequently chosen for surgery involving the oral cavity. In such cases, the endotracheal tube passes through the vocal cords into the trachea blindly, which may cause laryngeal trauma. We, therefore, studied the incidence of sore throat and hoarseness after fiberoptic nasotracheal intubation (n=44) and compared the results with those after conventional oral intubation (n=35). The incidence of sore throat was lower in the fiberoptic nasotracheal intubation group than in the conventional oral intubation group but the difference was not statistically significant (25.0%s 42.8%). The incidence of hoarseness after fiberoptic nasotracheal intubation was significantly lower than that after conventional oral intubation (4.5%s 34.3%,P<0.05). This study confirms a low incidence of laryngeal trauma in fiberoptic nasotracheal intubation.     

Morbid obesity and tracheal intubation

The tracheas of obese patients may be more difficult to intubate than those of normal-weight patients. We studied 100 morbidly obese patients (body mass index >40 kg/m(2)) to identify which factors complicate direct laryngoscopy and tracheal intubation. Preoperative measurements (height, weight, neck circumference, width of mouth opening, sternomental distance, and thyromental distance) and Mallampati score were recorded. The view during direct laryngoscopy was graded, and the number of attempts at tracheal intubation was recorded. Neither absolute obesity nor body mass index was associated with intubation difficulties. Large neck circumference and high Mallampati score were the only predictors of potential intubation problems. Because in all but one patient the trachea was intubated successfully by direct laryngoscopy, the neck circumference that requires an intervention such as fiberoptic bronchoscopy to establish an airway remains unknown. We conclude that obesity alone is not predictive of tracheal intubation difficulties. IMPLICATIONS: In 100 morbidly obese patients, neither obesity nor body mass index predicted problems with tracheal intubation. However, a high Mallampati score (greater-than-or-equal to 3) and large neck circumference may increase the potential for difficult laryngoscopy and intubation.     

Anesthetic management of an infant with Cornelia de Lange syndrome

We report anesthetic management of an infant with Cornelia de Lange syndrome. A 12-month-old girl with Cornelia de Lange syndrome was scheduled for ureterocystoneostomy because of vesicoureteral reflux. Preoperative physical examination suggested difficult tracheal intubation. After induction of anesthesia with sevoflurane (5%) in nitrous oxide (70%) and oxygen, a laryngeal mask airway (# 1.5) was inserted. A guide wire was inserted in the trachea through a laryngeal mask airway under direct vision of a fiberoptic bronchoscope. A tube-exchanger stylet was inserted around the guide wire after the laryngeal mask airway and fiberoptic bronchoscope had been removed. An endotracheal tube (ID 4.0 mm) was easily intubated around the tube-exchanger stylet. During the surgery, anesthesia was maintained with sevoflurane (2-3%) in nitrous oxide (50%) and oxygen. There was no perioperative pulmonary complication.     

Efficiency of a New Fiberoptic Stylet Scope in Tracheal Intubation

Background: Failed or difficult tracheal intubation is an important cause of morbidity and mortality during anesthesia. Although a number of fiberoptic devices are available to circumvent this problem, many do not allow manual control of the flexion of the tip and necessitate time-consuming preparation, special training, or the use of an external light source. To improve these limitations, the authors designed a new fiberoptic stylet scope (FSS) that has a simple form of a standard stylet with the fiberoptic view and maneuverability of its tip. This study was undertaken to prospectively evaluate the effectiveness of the FSS in tracheal intubation.

Methods: Thirty-two patients undergoing general surgery participated in this study. The authors used a standard laryngoscope only to elevate the tongue, then tracheal intubation was attempted with the glottic opening being viewed only through the FSS. The success rate, time necessary for intubation, hemodynamics, and adverse effects were recorded.

Results: The success rate of tracheal intubation on the first attempt using the FSS was 94% (30 of 32 patients), and the remaining two patients were intubated successfully on the second attempt. The mean time necessary for the intubation procedure was 29 +/- 14 s in all patients (mean +/- SD). Changes in hemodynamics during intubation were well within acceptable ranges. There were no major adverse effects, but minor sore throat (28%) and minor hoarseness (25%) on the first postoperative day.     

Tracheal intubation for two patients with lingual tonsil hyperplasia and prospect of difficult airway management

Lingual tonsil hyperplasia is rare, but may cause difficult or inpossible tracheal intubation. We experienced two cases of tracheal intubation for lingual tonsil hyperplasia. A 71-yr-old man was scheduled for resection and biopsy of symptomatic hypertrophied lingual tonsils. In this patient, we performed oro-tracheal intubation by rigid laryngoscopy from left oral angle, because left hypertrophied lingual tonsils are smaller than those on the right side. A 44-yr-old man was scheduled for resection of symptomatic hypertrophied lingual tonsils after lingual tonsillitis. In this patient, we performed nasotracheal intubation using fiberoptic bronchoscopy with assist of jaw-lift and tongue-extension. When an anesthesiologist can predict the abnormality of lingual tonsils, these methods might be recommended for difficult airway and intubation. However, it is necessary to prepare a difficult airway management set including laryngeal mask airway, intubating laryngeal mask airway, fiberoptic bronchos-copy and transcutaneous tracheotomy set. And most important is preliminary evaluation of airway and cautious planning of tracheal intubation.     

Efficiency of a new fiberoptic stylet scope in tracheal intubation

BACKGROUND: Failed or difficult tracheal intubation is an important cause of morbidity and mortality during anesthesia. Although a number of fiberoptic devices are available to circumvent this problem, many do not allow manual control of the flexion of the tip and necessitate time-consuming preparation, special training, or the use of an external light source. To improve these limitations, the authors designed a new fiberoptic stylet scope (FSS) that has a simple form of a standard stylet with the fiberoptic view and maneuverability of its tip. This study was undertaken to prospectively evaluate the effectiveness of the FSS in tracheal intubation. METHODS: Thirty-two patients undergoing general surgery participated in this study. The authors used a standard laryngoscope only to elevate the tongue, then tracheal intubation was attempted with the glottic opening being viewed only through the FSS. The success rate, time necessary for intubation, hemodynamics, and adverse effects were recorded. RESULTS: The success rate of tracheal intubation on the first attempt using the FSS was 94% (30 of 32 patients), and the remaining two patients were intubated successfully on the second attempt. The mean time necessary for the intubation procedure was 29+/-14 s in all patients (mean +/- SD). Changes in hemodynamics during intubation were well within acceptable ranges. There were no major adverse effects, but minor sore throat (28%) and minor hoarseness (25%) on the first postoperative day. CONCLUSIONS: Tracheal intubation using the FSS proved to be a simple and effective technique for airway management.     

A randomised comparison of C-MAC™ and King Vision® videolaryngoscopes with direct laryngoscopy in 180 obstetric patients

BackgroundCurrent evidence suggests that there is uncertainty about which videolaryngoscope performs best in obstetric anaesthesia. The aim of this study was to compare C-MAC and King Vision® videolaryngoscopes and direct laryngoscopy for tracheal intubation of patients undergoing caesarean section.MethodsOne hundred and eighty women were randomly assigned. The primary outcome was the time to tracheal intubation. Secondary outcomes were the time to the best laryngeal view, grade of Cormack and Lehane view, overall and first-pass success, intubation difficulty, the number of intubation attempts and optimisation manoeuvres; and complications.ResultsThe time to successful intubation, first-pass and overall success rates did not differ between the devices. The difficulty of intubation was less for C-MAC than King Vision® (P <0.001). No difference was observed between King Vision® and direct laryngoscopy (P=0.06) or C-MAC and direct laryngoscopy (P=0.05). King Vision® required the longest time to best laryngeal view (9 ± 6 s, P=0.028), had the highest rate of grade 1 view (47 (80%) patients, P <0.001), and the highest need for optimisation manoeuvres (59 (100%) patients, P <0.0001). Five minor complications were recorded with King Vision® and one with direct laryngoscopy.ConclusionsCompared to direct laryngoscopy, C-MAC and King Vision® did not prolong the time to intubation, supporting these videolaryngoscopes as primary intubation devices in obstetric anaesthesia. The C-MAC was easier to use and needed fewer additional manoeuvres than the King Vision®. The C-MAC may be better suited for tracheal intubation of obstetric patients undergoing caesarean section.     

Comparison of wire reinforced tubes with warmed standard tubes to facilitate fiberoptic intubation

STUDY OBJECTIVE: To compare the ease of insertion of a warmed standard tracheal tube to that of a wire reinforced tracheal tube when placed over a flexible fiberoptic bronchoscope. DESIGN: Randomized controlled trial. SETTING: Tertiary care hospital. PATIENTS: 50 patients undergoing elective general anesthesia. INTERVENTIONS: Patients' tracheas were intubated with a flexible fiberoptic bronchoscope and had either a standard or wire-reinforced tracheal tube inserted. If resistance was met, the tube was withdrawn, rotated, and readvanced. This was repeated two times. If unsuccessful, the flexible fiberoptic bronchoscope was removed, and intubation was attempted with the other type of tracheal tube. MEASUREMENTS: The ability to advance the tracheal tube was determined. MAIN RESULTS: There were no demographic differences between the two groups. There was a similar ease of advancement of the two tracheal tubes. CONCLUSIONS: When performing elective flexible fiberoptic bronchoscopy for intubation, we recommend using the less expensive warmed standard tracheal tube.     

Evaluation of tracheal intubation difficulty in patients with cervical spine immobilization: fiberoptic (WuScope) versus conventional laryngoscopy.

BACKGROUND: The WuScope is a rigid, fiberoptic laryngoscope designed to facilitate tracheal intubation without the need for head extension. The study evaluated the WuScope in anesthetized patients with neck immobilization. METHODS: Patients were randomized to one of two groups: those receiving fiberoptic laryngoscopy (WuScope, n = 43) and those receiving conventional laryngoscopy (Macintosh blade, n = 44). Manual in-line stablization of the cervical spine was done during intubation. Seven parameters of intubation difficulty were measured (providing an intubation difficulty scale score): number of operators, number of attempts, number of techniques, Cormack view, lifting force, laryngeal pressure, and vocal cord position. RESULTS: Successful intubation occurred in 95% of patients in the fiberoptic group and in 93% of patients in the conventional group. There were no differences in number of attempts. In the fiberoptic group, 79% of patients had an intubation difficulty scale score of 0, representing an ideal intubation: that is, one performed by the first operator on the first attempt using the first technique with full glottic visualization. Only 18% of patients in the conventional group had an intubation difficulty scale score of 0 (P < 0.001). More patients had Cormack grade 3 or 4 views with conventional than with fiberoptic laryngoscopy (39 vs. 2%, P < 0.001). Intubation times in patients with one attempt were slightly longer in the fiberoptic (median, 25th-75th percentiles: 30, 23-53 s) compared with the conventional group (24, 17-30 s, P < 0.05). Corresponding times in patients requiring > one attempt were 155 (range, 112-201) s and 141 (range, 95-186) s in the fiberoptic and conventional groups, respectively (P value not significant). CONCLUSIONS: Compared with conventional laryngoscopy, tracheal intubation using the fiberoptic laryngoscope was associated with lower intubation difficulty scale scores and better views of the laryngeal aperture in patients with cervical imnmobilization. However, there were no differences in success rates or number of intubation attempts.