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Percutaneous tracheostomy has become a common alternative to the classical open tracheostomy because of its convenience, cost effectiveness, and decreased complication rates. We retrospectively reviewed our intensive care practice using a guidewire dilatating forceps percutaneous tracheostomy technique with an endotracheal tube, as compared with the Classic Laryngeal Mask Airway (LMA) for these procedures. From 1998 to 2004, 274 patients underwent a tracheostomy procedure. Two-hundred-fifty-four (92.7%) of these patients underwent a guidewire dilatating forceps tracheostomy and 20 (7.3%) underwent a surgical tracheostomy. In the guidewire dilatating forceps group, 188 (74%) were performed by endoscopy via LMA-guided bronchoscopy, and 66 (26%) were performed through an endotracheal tube. Endoscopic views obtained via the LMA were subjectively better than those obtained with the endotracheal tube. Acute complications were significantly more frequent when using an endotracheal tube as compared with the LMA (6 of 66 versus 4 of 188; P = 0.022 Fisher's exact test, odds ratio = 4.6). There was a significant difference in terms of acute (10 of 254 versus 6 of 20; P < 0.001, odds ratio = 10.5) and chronic (0 of 254 versus 4 of 20; P < 0.001) complications between the 2 groups. There were no ventilatory complications or reports of gastric aspiration. The LMA provides a safe and effective alternative to an endotracheal tube for airway management during guidewire dilatating forceps tracheostomies in selected patients.
The use of a percutaneous tracheostomy (PT) technique has become a common alternative to the classical open tracheostomy technique. There are several reasons for this, including convenience (bedside technique), cost effectiveness, and infrequent complications (13). Techniques such as the percutaneous dilatational tracheostomy, the Ciaglia Blue Rhino, the guidewire dilating forceps, and the translaryngeal technique, are among the most common techniques used today (48). These techniques all have similar complication rates (911), which can occur early (during the procedure and <24 h) or late (>24 h after the procedure). Complications that can occur during these procedures include bleeding, creation of a false passage, pneumothorax, emphysema of the neck, puncture of the posterior wall of the trachea, and perforation of the esophagus. The risk of these complications can be dramatically reduced if the procedure is performed under continuous endoscopic guidance (11). Traditionally, endoscopy is performed through an endotracheal tube. Furthermore, when performed with an endotracheal tube, the procedure requires that the cuff of the endotracheal tube be deflated and the tube be withdrawn until the cuff is located at the level of the vocal cords. Failure to position the endotracheal tube correctly can result in further complications during the course of the procedure, such as rupture of the tube cuff, transection of the tube with the needle, inability to ventilate, and accidental tracheal extubation. Any of these complications can result in life-threatening hypoxia. Replacing an endotracheal tube with a Laryngeal Mask Airway (LMA) as a conduit for the fiberoptic bronchoscope avoids some of these risks and provides superior visualization of the trachea and larynx. Despite the theoretical advantages of the LMA, Ambesh et al. (12), found, in a comparative prospective study, that 33% of patients in the LMA group suffered potentially catastrophic complications, and that these patients were at significant risk for hypoxia and aspiration of gastric contents. Few studies have demonstrated the effectiveness and safety of the LMA during the percutaneous dilatational tracheostomy procedure (1315). Of these, only one (14) is a comparative prospective study and, although Dosemeci et al. did show fewer overall complications with the LMA, the difference was not statistically significant. Also, as this study was unblinded a bias was introduced. Because there is conflicting evidence in the literature regarding the safety and reliability of using the LMA in daily clinical activity for airway control during bronchoscopic-assisted guidewire dilatating forceps procedures, a retrospective investigation was performed at our institution.
After appropriate local ethics committee approval, we reviewed the medical records of 274 critically ill patients who consecutively underwent elective tracheostomies in our intensive care unit during a 6-yr period (January 1998 to October 2004). Standard indications and contraindications for the performance of PTs were used (4,5). The main indications for these procedures were: 1) prolonged tracheal intubation and 2) weaning of mechanical ventilation. Contraindications included patients having difficulty with oxygenation (positive end-expiratory pressure >20 cm H2O, Fio2 <0.7), presence of a large goiter, neck instability, severe clotting alterations, previous neck surgery, emergency surgery, <16 yr of age, and weight <40 kg. The guidewire dilatating forceps or Griggs technique was used in this study because the authors were most experienced with this PT technique. The procedure was done using continuous bronchoscopic guidance, with ventilation being performed through a Classic LMA (LMA North America, San Diego, CA) unless the patient had a contraindication to the use of a LMA, such as obesity, patients considered to be difficult to intubate (history of a difficult intubation, short thick neck, generalized edema, small receding chin, large tongue, thyromental distance of <3 finger breadths, reduced neck mobility), and those with significant inflammation of the upper airway (edema, laryngitis or epiglottitis) or those who required peak airway pressures >30 cm H2O (16,17). An LMA was also not used if the anesthesiologist preferred using an endotracheal tube for the procedure. All patients were fasted at least 6 h before the surgical procedure. Patients received ketamine 12 mg/kg or midazolam 0.10.2 mg/kg and fentanyl 12 µg/kg for sedation and atracurium 0.50.6 mg/kg for neuromuscular blockade. Immediately before the onset of the procedure, the fraction of inspired oxygen was increased to 1.0, the pharynx was suctioned, and the nasogastric tube was suctioned but left in situ during the procedure. All patients' heads were extended with a roll placed under their shoulders. The neck and the upper thorax were prepared with tincture of iodine and local anesthesia was provided by injection of 2% lidocaine with epinephrine 1:100,000 to improve patient tolerance for the procedure and reduce bleeding. In Group I, the endotracheal tube was removed and an LMA was inserted. The LMA size was chosen as recommended by the manufacturer: #3 <50 kg, #4 5070 kg, and #5 >70 kg. In Group II, the endotracheal tube was withdrawn under direct vision, with a laryngoscope, until the inflated cuff was located between the vocal cords. Once adequate oxygenation and ventilation was confirmed, the PT commenced. The guidewire dilatating forceps technique was performed with a Percutaneous Tracheostomy Kit (SIMS Portex Limited, Hythe, Kent, UK) (Fig. 1). The trachea was entered with a cannulated needle followed by passage of a guidewire once the needle was removed. The position and depth of the tracheal puncture, as well as the position of the guidewire, were routinely checked with a fiberoptic bronchoscope in all patients. Subsequently, the forceps were used to dilate the tracheal wall (Fig. 2).
Patient demographics were recorded. The patients were monitored in the intensive care unit as per standard protocol. Any complications occurring during the procedure or within 24 h after the procedure were recorded as early complications. Any complications that occurred more than 24 h after the procedure, but before discharge, were recorded as late complications.
Patients were 63 ± 8 yr of age, with 58.4% males. Twenty of 274 (7.3%) patients underwent surgical tracheostomies as they had a contraindication to the PT technique. Of the 254 patients who underwent a guidewire dilatating forceps PT, 188 (74%) had the procedure performed with an LMA (Group I) and 66 (26%) had the procedure done with an endotracheal tube (Group II). There was no significant difference between groups in the time that it took to perform the guidewire dilatating forceps PT or in the ease of insertion of the tracheostomy. On average, the procedures took 8 ± 5.25 min to perform. LMA ventilation was adequate in all patients when used, and no patients required reintubation. Anesthesiologists involved in the procedure were required to record their subjective findings regarding the performance of the procedure, including level of difficulty and ease of visualization of airway structures. According to the subjective responses of the operators, visualization of the larynx and the trachea, as well as accuracy of cannula placement, were better in Group I. Table 1 demonstrates early and late complications between the study groups. Four of 188 (2.12%) patients in Group I experienced complications. Three patients (1.59%) experienced bleeding and 1 patient (0.53%) developed a pneumothorax within the first 24 h after the procedure. Six of 66 (9.09%) patients in Group II experienced complications. Bleeding, accidental extubation, and rupture of the endotracheal tube cuff occurred in 6 patients (2 of each) within the first 24 h. There were no late complications in either group. Of the patients who underwent open tracheostomy (n = 20), 6 (30.0%) experienced bleeding within the first 24 h and 3 (15.0%) experienced bleeding after the first 24 h. One (5.0%) patient developed tracheal stenosis.
Significant differences were found in acute complications (bleeding, hypoxia, pneumothorax) between the Classic LMA and endotracheal tube groups (4 of 188 versus 6 of 66; P = 0.022 Fisher's exact test, odds ratio = 4.6). Significant differences were found in acute complications (10 of 254 versus 6 of 20; P < 0.001, odds ratio = 10.5) and chronic complications (tracheal stenosis) (0 of 254 versus 4 of 20; P < 0.001) between the guidewire dilatating forceps and surgical tracheostomy procedures.
The guidewire dilatating forceps technique described by Griggs et al. (18) has become a popular technique for PT, particularly in European countries. It has been demonstrated to be a safe and effective technique (4). This finding was confirmed in our study, as the overall complication rate for guidewire dilatating forceps PT was significantly less than for surgical tracheostomies. However, as previously mentioned, this procedure is not without complications. The early and late complications associated with this technique are listed in Table 2. The guidewire dilatating forceps PT technique has a similar rate of complications as compared to other PT techniques (4,19).
By performing this procedure under continuous bronchoscopic guidance, the needle and guidewire can be correctly placed and dilation can be carefully performed under fiberoptic visualization, thus reducing the risk of complications. However, to accomplish this through an endotracheal tube, the endotracheal tube must be withdrawn so that the cuff is located at the level of the vocal cords and the cuff must be partially deflated. This could lead to accidental extubation and loss of the airway, with fatal consequences. Also, withdrawing the endotracheal tube does not guarantee that the endotracheal tube or its cuff will not get punctured. This is because the anatomical length of the adult human larynx is 3.44.4 cm (20). In a size 8.09.0 mm endotracheal tube, the average length of the cuff is 3 cm and the average length of the tube from the distal end of the cuff to the tip of the endotracheal tube is 3 cm; therefore, it is possible that even if the endotracheal tube is withdrawn, the tube itself or the cuff could be punctured by the tracheostomy needle. This could lead to a loss of airway pressure and an inability to effectively ventilate the lungs, possibly resulting in devastating consequences. An additional problem with the endotracheal tube is visualization with the fiberoptic bronchoscope. To obtain a clear, undistorted view of the procedure through the fiberoptic bronchoscope, the tip of the fiberoptic bronchoscope should be located at or beyond the tip of the endotracheal tube. As discussed above, this may be positioned directly at or distal to the tracheostomy needle insertion point, and therefore the view may be suboptimal to assess correct placement of the needle and guidewire. The Classic LMA may be used to overcome these potentially devastating complications. This study demonstrates that the use of a Classic LMA for airway management during guidewire dilatating forceps PT procedures had significantly fewer complications than when performed using an endotracheal tube. In addition to our study, numerous other studies have shown that the Classic LMA facilitates fiberoptic guidance and allows an undistorted view of the larynx and trachea, thus assisting the operator to confirm accurate positioning of the needle in the trachea (1315,21,22). The LMA is easy to insert blindly and is a safe and effective means of providing positive pressure ventilation. Also, because the LMA is a supraglottic ventilatory device, the risk of penetrating it with the tracheostomy needle is virtually eliminated. On the other hand, the Classic LMA does not protect against aspiration (23); therefore it should be avoided in patients who are at high risk for aspiration. As an added precaution, an orogastric or nasogastric tube should be placed and the stomach contents suctioned before the procedure and it should remain in situ throughout the procedure. Gastroesophageal reflux disease was not considered a contraindication to the use of a LMA in our study, as those with history of gastroesophageal reflux disease were fasted for at least 6 hours before the procedure and their stomach contents were suctioned. Furthermore, the ProSeal LMA, a laryngeal mask with an esophageal vent, could be used to allow direct gastric drainage, thus minimizing the risk of aspiration and regurgitation (24). Also, although we considered obesity a contraindication for the use of a Classic LMA in our study, Sustic et al. (25) report a case in which a LMA was used successfully during insertion of a PT using ultrasound guidance. It is also important to mention that although an LMA does not protect against aspiration in high risk patients, neither does an endotracheal tube with a deflated or ruptured cuff. The limitations of this study are as follows: this was a retrospective study, thus the patients were not randomized, the operators were not blinded, and the data are not comparative. The patients who had the procedure performed with an endotracheal tube were usually more critically ill and were assessed to have more difficult airways. Furthermore, the degree of visualization through either the Classic LMA or the endotracheal tube was subjective, and there was no objective method used to grade the degree of visualization. Despite the limitations of this study, we demonstrated that the Classic LMA is a safe and effective alternative to the endotracheal tube for airway management during guidewire dilatating forceps PT in selected patients. This represents the largest analysis of using LMAs for airway management during these procedures. Although using LMAs avoids some of the inherent risks associated with percutaneous tracheostomy procedures, there are limitations with their use. Although the ProSeal LMA may be more beneficial as compared with the Classic LMA during PT, the Classic LMA remains a valuable option when reasonable precautions are taken. Further investigation is required to determine which patients will benefit most from this method. Finally, further studies using the ProSeal LMA for airway management in these procedures are warranted.
We would like to thank Andrea Nicolini, MD and Maurizio Genovesi, MD for their support and valuable contributions. We thank Professor Flavia Petrini, MD, for her help in the revision of the manuscript.
Accepted for publication March 30, 2006.
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