Hans J. Gerig

Validation of a simple algorithm for tracheal intubation: daily practice is the key to success in emergencies--an analysis of 13,248 intubations.

A fundamental skill of the anesthesiologist is airway management. We validated a simple endotracheal intubation algorithm with a large proportion of fiberoptic tracheal intubations used for years in daily practice. Over 2 yr, 13,248 intubations (>90% of all intubations, including obstetrics and ear, nose, and throat patients) in a heterogeneous patient population at our acute care hospital were evaluated prospectively. About 80 physician and nurse anesthetists were involved. Once the indication for intubation (oral or nasal) was established, the first step was to choose between the primary conventional technique (laryngoscope with Macintosh blades) and the primary fiberoptic technique. For the conventional technique, a well defined procedure had to be followed (maximum of two attempts at intubation; if unsuccessful, switch to secondary oral fiberoptic intubation). For the primary fiberoptic technique, the anesthesiologist had to decide between nasotracheal intubation in awake patients and oral intubation in anesthetized patients. Fiberoptics were used for 13.5% of the intubations. By following our algorithm, intubation failed in 6 out of 13,248 cases (0.045%; 95% confidence interval 0.02%–0.11%). We demonstrate that a simple algorithm for endotracheal intubation, basically limited to fiberoptics as the only aid, is successful in daily practice. Only methods that are practiced daily can be used successfully in emergencies. Implications The aim of this investigation was to validate a simple tracheal intubation algorithm used in daily practice for years as a quality control exercise. With the exception of the guidewire, the only airway management instrument used was the fiberoptic bronchoscope. Of 13,248 intubations evaluated (90.6% of all intubations), only six patients (0.045%) could not be intubated by following our algorithm. The high proportion of primary fiberoptic intubations (12.1% of all intubations) has resulted in a corresponding degree of practice and experience with this method, with the consequence that the number of unanticipated failed intubations is very small. Daily practice is the key to success in the emergency situation.

Algorithms for management of the difficult airway.

Purpose of review The purpose of this review is to examine recent evidence for the management of the difficult airway. Recent findings Recent findings still recommend the importance of a predefined, simple strategy for both the anticipated and unanticipated difficult airway. For the former, awake fiberoptic intubation is still the ‘gold standard’. For management of the unanticipated difficult airway, the use of the laryngeal mask airway (LMA), intubating laryngeal mask airway (ILMA), the ‘gum elastic bougie’ and fiberoptics are recommended. If intubation and ventilation fails, cannula or surgical cricothyroidotomy should be an early consideration. Summary This review of algorithms for management of the difficult airway strengthens several generally accepted crucial points. What is always needed is expertise, which one can only get and maintain by daily practice.

Fiberoptically-Guided Insertion of Transtracheal Catheters

IMPLICATIONS Regular use of the transtracheal catheter (TTC) both offers an opportunity for training for the difficult airway and facilitates elective endoscopic surgery. Fiberoptic guidance and exploratory puncture improve the insertion of the TTC.

Fiberoptic intubation and laryngeal morbidity: a randomized controlled trial.

Background:Tracheal intubation with neuromuscular blocking agents is associated with a low incidence of minor vocal cord sequelae (8%). The aim of this noninferiority trial was to demonstrate that the frequency of vocal cord sequelae after fiberoptic intubation with a flexible silicone tube without neuromuscular blocking agents was less than 25% (maximum tolerable inferiority). Methods:Two-hundred seventy patients were prospectively randomized to two groups. All intubations were performed by anesthesiologists with extensive experience in fiberoptic and conventional techniques. Fiberoptic nasotracheal intubation consisted of a bolus dose of 2 &mgr;g/kg fentanyl; 0.25 ml cocaine instillation, 10%, into nasal canals; cricothyroid injection of 2 ml lidocaine, 1%; bronchoscopy; administration of 0.3 mg/kg etomidate; and advancing a flexible silicone tube after loss of consciousness. Orotracheal intubation was performed with a polyvinyl chloride tube after induction with 2 &mgr;g/kg fentanyl, 2 mg/kg propofol, and 0.6 mg/kg rocuronium. Patients were examined by laryngoscopy before surgery, 24 h after surgery, and daily until complete restitution. Postoperative hoarseness was assessed by a standardized interview. Results:The incidence of vocal cord sequelae was 11 out of 130 (8.5%) in the fiberoptic group versus 12 out of 129 (9.3%) in the control group (chi-square = 0.057, df = 1, P = 0.81; upper limit of the one-sided 95% confidence interval for the difference: +5.1%). There were no persistent injuries. The incidence of postoperative hoarseness was 4% in both groups. Conclusions:Because fiberoptic intubation without neuromuscular blocking agents is safe regarding vocal cord sequelae, routine use is justified for anesthesiologists experienced in this technique.

comparison of etomidate and propofol for fibreoptic intubation as part of an airway management algorithm : a prospective, randomized, double-blind study *

Background and objective: In our algorithm for management of the anticipated difficult airway the induction agent (etomidate) is administered after the tip of the fibreoptic is placed in the trachea but before the tube is advanced over it. In a previous investigation we demonstrated the safety of this method. Due to its popularity as an induction agent, some would like to replace etomidate with propofol. However, because rapid recovery of spontaneous breathing is crucial with this technique, substitution might not be advisable. We compared the speed of recovery of spontaneous breathing after fibreoptic intubation between etomidate and propofol. Methods: In this prospective, randomized, double‐blind study we used either 0.2 mg kg−1 etomidate or 2 mg kg−1 propofol for induction. Our technique of nasotracheal fibreoptic intubation consists of using fentanyl, cocaine instillation into the lower nasal canals, cricothyroid injection of lidocaine, performing bronchoscopy, administration of etomidate and advancing the tube after loss of consciousness. We measured time to loss of consciousness, time to recovery of spontaneous breathing, lowest bispectral index value and time to lowest value. Results: Time to loss of consciousness did not differ. The time to recovery of spontaneous breathing differed significantly: the median time (interquartile range [range]) for etomidate was 81 s (62‐102 [0‐166]), and for propofol 146 s (95‐260 [65‐315]); P = 0.001. The lowest bispectral index values were not different. The time of the lowest bispectral index values differed significantly: for etomidate 58 s (51‐68 [38‐100]), and for propofol 90 s (52‐125 [38‐172]); P = 0.015. Conclusion: For nasotracheal fibreoptic intubation, where the tube is advanced after induction of anaesthesia, we still recommend etomidate because spontaneous breathing recovers faster than with propofol.

ventilatory effects of etomidate versus propofol for awake fiberoptic intubation - preliminary results : a-253

fibrescope, loaded with an ETT, was inserted through the second nostril to intubate the trachea. We used 6.0/6.5/7.0 mm north polar preformed RAE tubes. If resistance was felt on tube insertion, the ETT was withdrawn 1 cm, rotated 90° and advanced again. If difficulty persisted, the manoeuvre was repeated with 180°, 270° and 360° rotation. Results: We experienced 10 cases of impingement (23%). The site of the impingement was the right arytenoid in five cases. In two cases, the ETT migrated into the hypopharynx. Left arytenoid, left vocal cord and right piriform fossa were the site of impingement in one case each. Rotation was successful in all 10 cases ( 90° in three cases, 180° in four and three cases requiring 360°). Despite these rotational manoeuvres at the proximal end of the ETT, we observed only partial rotation transferred to its distal tip in four cases. In six cases, the ETT tip only moved up and/or sideways. Conclusions: During NFOI, impingement of ETT tip occurs at the lower areas of the laryngeal inlet (most commonly right arytenoid) rather than the epiglottis. Rotation of the ETT is a reliable solution, but it is of interest that proximal ETT rotation does not always result in rotation, but rather up or sideways movement of the distal ETT. References: 1 Hughes S, Smith JE. Nasotracheal tube placement over the fibreoptic laryngoscope. Anaesthesia 1996; 51:1026–8. 2 Katsnelson et al. Anesthesiology 1992; 76:151–2.