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The Esophageal-Tracheal Combitube
Anesthesiology Clin N Am 20 (2002) 893 – 906
The Esophageal-Tracheal Combitube Luis A. Gaitini, MD a,*, Sonia J. Vaida, MD a, Felice Agro, MD b a
Anesthesiology Department, Bnai-Zion Medical Center, Faculty of Medicine, Technion, 47 Colomb Street, POB 4940, 31048, Haifa, Israel b Anesthesiology Department, University School of Medicine, Campus BioMedico, Via Longoni 69 – 83 00155, Roma, Italy
History One of the most challenging tasks in cardiopulmonary resuscitation (CPR) or difficult intubation is to provide rapidly a patent airway to facilitate adequate ventilation. Endotracheal intubation is the gold standard for airway management; however, on some occasions, it may be difficult or impossible even for skilled anesthesiologists. Many alternative airway devices have been used in emergency before the Esophageal-Tracheal Combitube (ETC). The esophageal obturator airway (EOA) [1] was first described in 1968 by Don Michael et al as an alternative to the endotracheal airway during emergency intubation. The main advantage of such a device is that direct laryngoscopy is not required and training in its use would therefore require less skill and medical input [2,3]. Nevertheless, it soon became apparent that considerable technical difficulties were associated with this device [4]. The main complications associated with the use of the EOA were leakage of air around the facemask resulting in inadequate ventilation [4,5], inadvertent or unrecognized tracheal placement [6 – 9], and esophageal or gastric ruptures [10 – 12]. The ETC was designed to overcome the limitations of the EOA, effectively combining the functions of the EOA and a traditional endotracheal tube (ETT). It was invented and brought into clinical use in 1987 by Frass in cooperation with Frenzer and Zahler of Moedling, Austria, and Vienna, Austria [13].
* Corresponding author. E-mail address: [email protected] (L.A. Gaitini, MD). 0889-8537/02/$ – see front matter D 2002, Elsevier Science (USA). All rights reserved. PII: S 0 8 8 9 - 8 5 3 7 ( 0 2 ) 0 0 0 2 1 - 4
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Functional anatomy The ETC (Tyco-Kendall, Sheridan, Mansfield, MA) is a disposable polyvinyl chloride double lumen supraglottic airway device with two inflatable balloons (Fig. 1). The two lumens are divided by a partition. Ventilation is possible with either tracheal or esophageal intubation, but is usually enters the esophagus in more than 95% of cases [14,15]. The pharyngeal lumen [16] has a blocked distal end and a blue proximal end with a standard 15-mm connector. This lumen communicates with the airway by eight oval-shaped holes (7 3 mm) positioned at the level of the lower pharynx.
Fig. 1. The Esophageal-Tracheal Combitube.
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The tracheal lumen has a shorter clear proximal portion with a standard 15-mm connector and it is open at the distal end. A black ring around both lumens is intended to be a depth marker, and, when placed between incisors or the alveolar ridges, results in an incisor to ETC tip distance of 22 mm. An oropharyngeal balloon proximal to the pharyngeal perforations of the esophageal lumen serves to seal the oral and nasal cavity, and a distal balloon situated proximal to the distal opening of the tracheal lumen serves as a seal of either the esophagus or the trachea, depending on which of these the ETC has been sited. The ETC is available in two sizes, the small adult ETC 37 F, recommended for patients with a height between 4 and 6 feet (approximately 120 to 180 cm), and the large adult ETC 41 F, for patients taller than 6 feet (approximately 180 cm), with an overlap between both sizes [17]. Walz et al [18] report the successful use of the ETC 37 F in patients up to 198 cm height, recommending its use independent of an upper limit height. The ETC 37 F is prepackaged with a large syringe, predrawn to 85 mL (41 F: 100 ml), and a small syringe, predrawn to 12 mL (41 F: 15 ml). The large syringe is color-coded to ensure inflation of the oropharyngeal proximal balloon via the valve with the blue pilot balloon. The kit also provides a 10 F (41 F: 12 F) suction catheter as well as a deflection elbow to avoid soiling of the rescuer by gastric contents. The ETC is delivered in a hard tray, as a roll-up kit (both kits containing all accessories), or as a single kit (containing the ETC only). Although the ETC was initially designed as a disposable single-use device, according to a recent publication the microbiological, microstructure, and material science examination prove that reprocessing of multiple reused (four times) ETC is possible and safe [19].
Insertion The ETC is inserted blindly in a curved downward movement by grasping the back of the tongue and jaw between thumb and forefinger and lifting the jaw until the printed ringmarks lie between the teeth or alveolar ridges in edentulous patients. The head remains preferably in neutral position; some clinicians prefer to extend the head or use a small cushion. The typical sniffing position should be avoided. The ETC should be introduced by a gentle movement, never using force (Fig. 2). Next the proximal balloon of the 37 F and 41 F ETC is inflated with 85 mL and 100 mL of air, respectively. During inflation, the tube moves slightly out of the patient’s mouth. Then the distal balloon is inflated with 10 to 12 mL and 10 to 15 mL of air, respectively. The ‘‘big’’ syringe’’ should be used to inflate the ‘‘big blue balloon’’ first. To avoid overinflation of the distal balloon and subsequent esophageal trauma, remember BBBB (Big Blue Balloon Before) (Fig. 3).
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Fig. 2. Insertion technique of the Esophagel-Tracheal Combitube.
The proximal balloon when inflated is pressed against the base of the tongue and closes the soft palate, thereby sealing the hypopharynx against the oral and nasal cavities. The ETC is correctly positioned when the ventral part of the proximal balloon reaches the posterior part of the hard palate, thus ensuring a strong anchoring, which is helpful during ventilation. Although the ETC may be inserted blindly, laryngoscopy may be performed to enhance placement of the device [20].
Fig. 3. Inflation of the balloons of the Esophagel-Tracheal Combitube.
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To facilitate insertion, it is recommended to bend the ETC to a 90° angle for several seconds at the point between the proximal and distal balloon. This accentuation of the curvature alleviates insertion along the tongue (‘‘Lipp maneuver’’) (M. Lipp, personal communication 1996). The most common cause of difficulty of ventilating the patient via the ‘‘paryngeal lumen,’’ despite appropriate intraesophageal placement, is that the ETC is inserted too deeply [20]. When the ETC is inserted too deeply, the ventilation pharyngeal holes may be inside the esophagus and unable to have gaseous communication with the larynx. When difficulty with ventilation is encountered after an eventful ETC insertion,the recommendation is to deflate both balloons, pull the ETC out 1 to 2 cm, reinflate the balloons, and try instituting ventilation again.
Placement confirmation After insertion of the ETC, a correct identification of the distal lumen as being intraesophageal or intratracheal is required. Because of the high probability that the tube will be placed into the esophagus, after blind insertion, test ventilation is recommended through the longer blue tube leading to the esophageal lumen. Air passes into the pharynx and from there over the epiglottis into the trachea because the mouth, nose, and esophagus are blocked by the balloons (Fig. 4). Auscultation of breath sounds in the absence of gastric insufflation confirms adequate ventilation when the ETC is in the esophagus. Ventilation is then continued through this lumen. In this position, gastric contents can be suctioned through the other unused ‘‘tracheal’’ lumen. If no breath sounds are heard over
Fig. 4. The Esophagel-Tracheal Combitube in esophageal position.
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Fig. 5. The Esophagel-Tracheal Combitube in tracheal position.
the lungs in the presence of gastric insufflation, the ETC has been placed into the trachea (Fig. 5). Without changing the position of the ETC, ventilation is changed to the shorter clear tube leading to the tracheal lumen and position is again confirmed by auscultation. In addition, capnography is mandatory to confirm adequate ventilation. A selfinflating bulb can quickly and reliably identify esophageal or tracheal placement of the ETC and facilitate proper selection of the correct ventilatory lumen [21,22].
Uses and indications Cardiopulmonary resuscitation Out-of-hospital The ETC is used mainly for airway control in emergencies when establishment of an ETT is not immediately possible [23,24]. The double-lumen/double-balloon design of the ETC permits rapid institution of rescue ventilation after blind insertion into either esophagus or trachea and affords protection from regurgitation or aspiration. In a prospective study, Atherton and Johnson [15] investigated the ability of paramedics in a nonurban emergency medical services system to use the ETC in prehospital cardiac arrest patients. The ETC was successfully inserted in 71% of cases when used as a first-line airway adjunct and 64% of the time in patients who could not be intubated with an ETT using direct laryngoscopy. A follow-up study of the paramedics conducted 15 months later demonstrated inadequate skill retention.
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In a series of 470 patients reported by Rumball and MacDonald [23], the ETC was rated best when comparing the device with the pharyngeal tracheal lumen airway (PTLA), the laryngeal mask airway (LMA), and the oral airway (OA)/ mask when used in conjunction with a bag-valve device by emergency medical technicians (EMTs) during cardiorespiratory arrest. Success rate of insertion and ventilation was significantly higher with the ETC (86% successful insertion rate) despite the fact that some of the EMTs had been previously trained to use the LMA in the operating room. In a retrospective study of 12,020 cases of nontraumatic cardiac arrest, Tanigawa and Shigematsu [24] find the ETC to have a better first attempt insertion rate (82.4%) than either the esophageal gastric tube airway (EGTA) or the LMA. Also, success rates for ventilation and for insertion are significantly higher with the ETC. In a recent study [25], emergency medical technicians – defibrillation (EMTDs) were trained to use the ETC in prehosopital environment in a 18-month prospective field study. ETC insertions were attempted in 195 prehospital patients in cardiopulmonary arrest with an overall successful intubation rate of 79%. When necessary during CPR, epinephrine can be applied via the pharyngeal lumen of the ETC in a ten fold higher dosage with similar effects on plasma epinephrine levels and hemodynamic variables as with the endotracheal administration [26]. ETT remains the gold standard for ventilation and protection for aspiration, but the ETC is a viable choice with a high success rate when used as an initial airway by trained paramedics. While insertion of the ETC requires a lesser degree of skill than does ETT, it is mandatory that continuing education and testing reinforce the requisite skills for the successful use of the ETC. In-hospital CPR Several studies prove the effectiveness of the ETC in ventilating patients during CPR in intensive care settings [14,27,28]. In a 1987 report [27], 21 patients requiring CPR were intubated with the ETC. Acceptable blood gas results were achieved in all patients, despite the fact that three patients had vomited prior to introduction of the ETC. These results encouraged further studies into the use of the ETC during CPR. Frass et al [14] checked the effectiveness of ventilation in 31 patients requiring CPR after cardiac arrest calls, either in intensive care or in a general hospital ward setting. The first part of the study examined the adequacy of ventilation by ETC and a reservoir bag, using an estimated inspired oxygen concentration of 40%. The second part compared the efficiency of ventilation with the ETC with conventional ETT in a group of 15 mechanically ventilated patients. Patients ventilated using the ETC were reported to have significantly higher mean arterial oxygen tensions than those in the ETT group. In post mortem examinations of patients who died within 24 hours after CPR, there was no evidence of pulmonary aspiration.
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In another study [28], the promptness and effectiveness of ventilation using the ETC for airway management during CPR was investigated. The time required for correct placement was significantly shorter in the ETC group (27.3 ± 8.4 s) compared with the ETT group (39.7 ± 10.0 s), despite the fact that more time was required for balloon inflation with the ETC. The differences in total intubation time were thought to be partially explained by the fact that direct laryngoscopy is unnecessary to position the ETC correctly. Ventilation via the ETC was demonstrated to produce higher mean arterial oxygen tensions than ventilation via the tracheal tube. The postulated explanation for the higher PaO2 in the patients ventilated with an ETC is a prolonged respiratory flow time and an increase in expiratory resistance resulting in a small degree of auto-PEEP (2 cm H2O). Additionally, the vocal cords are not by-passed with the ETC compared with the situation when an ETT is used [29]. Staudinger et al evaluated [30] the safety and effectiveness of the ETC as used by intensive care nurses under medical supervision compared with endotracheal intubation performed by intensive care physicians during CPR. Intubation time was shorter for the ETC. Blood gases for each device showed comparable results; the arterial oxygen tension was slightly higher during ventilation with the ETC. The study suggests that the ETC as used by intensive care nurses is as effective as the endotracheal airway by intensivists during CPR. Trauma Despite the fact that the Advanced Trauma Life Support [31] protocol does not include the ETC as an alternative airway device in cases of failed intubation, the use of the ETC in trauma is described in several studies [32 –34]. Flight nurses are trained in the use of ETC by mannequin simulation, videotape review, and didactic session. ETC insertion is attempted after failure of two or more attempts at orotracheal rapid-sequence induction and was successful in all ten patients in whom it was attempted. Seven patients requiring ETC had mandible fractures [32]. In a prospective study, Calkins and Robinson [33] compare the ability of Special Operations Corpsmen to use the ETT, LMA, or ETC under simulated combat conditions, concluding that, on occasion, an advanced combat casualty care provider may be unable to place an ETT; the LMA and ETC are useful alternatives in this situation. A recent study reports the effectiveness of ETC as an adjunct for paramedic rapid sequence induction when orotracheal intubation is unsuccessful, recommending increased minute ventilation to avoid hypercapnia [34]. ETC was successful in 96.7% of intubation attempts. Difficult airways The American Society of Anesthesiologists Task Force on Management of the Difficult Airway recommends use of the ETC in addition to the LMA, jet
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ventilation, and surgical airway when intubation problems occur in patients with a previously unrecognized difficult airway, especially in a ‘‘cannot ventilate, cannot intubate’’ situation [35]. Its use for difficult airway management also has been included in the ‘‘Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiac Care’’ of the American Heart Association [36]. Furthermore, the ETC was included in the ‘‘Guidelines of the European Resuscitation Council’’ in 1996 [37]. There are several reports of the effective use of the ETC in cases of difficult or failed endotracheal intubation [38 – 43]. Although it is possible to maintain an airway with the ETC [44], endotracheal intubation remains the preferred method for definitive or protracted securing of the airway. Therefore, exchange of the ETC with an ETT may often be desirable in continued management of the airway, and several techniques of ETC – ETT exchange under fiberoptic vision are described [45 – 47]. Kraft et al [45] redesigned the ETC by replacing its two proximal perforations with a larger hole, consequently making possible the passage of a fiberoptic bronchoscope through the ETC. In this technique, a guidewire is then passed through the fiberscope into the trachea, the ETC and fiberscope scope removed, and an ETT passed over the guidewire which has been left in place. This technique requires brief abdication of the airway after withdrawal of the fiberscope and ETC and until passage of an ETT over the guide wire. Ovassapian et al [46] inserted the fiberoptic bronchoscope orally alongside the ETC while the patients were paralyzed and ventilated, with an 85% success rate. Gaitini et al [47] describe a successful airway exchanges without interruption of airway control or ventilation, through nasal fiberoptic intubations in 18 spontaneously breathing patients and in 15 patients during controlled ventilation. The study suggests that spontaneous ventilation significantly improves the effectiveness of the technique, making identification and exposure of the epiglottis and the larynx easier. This airway exchange methods can be of value in situations demanding definitive airway control (eg, specific surgical procedures), when prolonged mechanical ventilation is needed, and for suctioning the trachea when necessary. In addition, the ETC is successfully used for maintenance of ventilation during percutaneous dilatational tracheostomy [48]. Elective surgery The ETC has been used and studied during routine general anesthetics. [18,43,48 –50] A recently published series of 200 cases proves the safety and effectiveness of the ETC in primary airway management for routine surgery with both mechanical and spontaneous ventilation of patients. In 97% of patients, excellent oxygenation, ventilation, respiratory mechanics, and hemodynamic stability are achieved. The duration of surgery is between 15 and 155 min. These investigators suggest that continued airway management with an ETC that has been placed is a reasonable option in many cases. Having thus secured the
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airway, it may not be necessary to abort the anesthetic or to continue with further airway management efforts [44]. In series of 25 patients undergoing elective surgery, Urtubia et al [49] report that ventilation is performed easily without signs of gastric insufflation. Recently, Hartmann et al [50] published a study on the ETC 37 F as an alternative airway for ventilatory support during gynecological laparoscopy. Airway management was performed with either ETC or tracheal intubation. Time for the ETC insertion while using a laryngoscope was 16 seconds. Peak airway pressures with the ETC were 25 ± 5 cm H2O. An airtight seal was obtained using air volumes of 55 ± 13 mL (proximal balloon) and 10 ± 1 mL (distal balloon). Another study by Hoerauf et al [51] dealing with patients undergoing elective surgery investigates waste gas exposure to sevoflurane and nitrous oxide during anesthesia using the ETC 37 F. Concentrations of sevoflurane and nitrous oxide are measured at the patient’s mouth and within the anesthesiologist’s breathing zone using direct spectrometer analysis. Results show that the ETC provides a seal as good as an ETT. Walz et al [18] report adequate oxygenation and ventilation in 104 patients undergoing automatic implantible cardioverter defibrillation implantation during a period of 45 to 360 min.
Advantages The ETC provides rapid and easy airway control without the need for direct laryngoscopy and neck or head movement with firm fixation of the device after inflation of the proximal balloon [52]. It works equally well in tracheal or esophageal position. The ETC can be placed by anesthesiologists with relatively little formal training [20] and by relatively inexperienced personnel. [15,25,30]. The ETC minimizes the danger of pulmonary aspiration [14,49]. The design of the proximal balloon and the distal balloon protects the airway from esophageal and gastric contents, blood, and debris [14]. In the esophageal position, the unused tracheal lumen also helps to decrease the likelihood of aspiration by immediate decompression of the stomach and by provision of a route for evacuation of gastric fluid. Urtubia et al [49] studied the protection offered by the ETC against aspiration by administrating methylene blue orally before anesthesia to 25 patients. There were no traces of methylene blue in the hypopharynx as investigated by direct laryngoscopy performed before the insertion of the ETC and after its removal. In 25 cases of laparoscopic cholecystectomy with mechanical ventilation using the ETC, no gastric insufflation could be observed in the beginning or end of surgery, as recorded by video films [53]. Relatively high airway pressure can be obtained with mechanical ventilation [44,50]; however, because of the design of the ETC, the delivered oropharyngeal pressure (presumably a reflection of intratracheal pressure) is
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significantly lower than the pressure measured at the anesthesia breathing system [54].
Disadvantages, contraindications, and complications Disadvantages include the impossibility of suctioning the trachea in esophageal position and possible esophageal damage. The contraindications to using the ETC include height less than four feet, intact gag reflexes, esophageal abnormalities, known ingestion of caustic substances, and glottic and supraglottic airway obstruction. The ETC cannot be recommended for use in patients whose necks are already immobilized in rigid cervical collars; however, it may be inserted successfully with a rigid collar in place, after temporary removal of the anterior part of the collar while the head is maintained with in-line mobilization [55]. There are few reports of esophageal perforation associated with the use of the ETC [24,56,57]. In a series of 1130 prehospital cardiac arrests managed with the ETC [56], eight patients presented with subcutaneous emphysema. Five of these eight patients had autopsies performed and two of these revealed longitudinal transparietal tears of the anterior wall of the esophagus. In these cases, the distal balloon was over-inflated with 20 to 40 mL of air (instead of 10 to15 mL with the ETC 37 F or 15 mL with the ETC 41). The potential for injury to the pharyngeal mucosa from excessive pressure exerted by the proximal balloon of the ETC is described [55,58]. A large inflation volume of the proximal balloon may tear the mucosa by stretching it, especially the posterior pharyngeal wall, [58] causing postoperative sore throat or dysphagia [55,58]. When the pressure of the proximal balloon transmitted to the pharyngeal mucosa exceeds capillary perfusion pressure of the mucosa tissue, ischemia is possible. The reported incidence of postoperative sore throat after use of the ETC varies from 25% to 48% [38,58]. Recent studies indicate that the proximal balloon fill volume needed to achieve an airway seal is substantially less than that recommended by the manufacturer [49,59].The proximal balloon inflation volume for ETC 37 F to prevent an air leak was estimated at 40 to 85 mL of air [49]. Gaitini et al [59] find a minimal inflation volume for an adequate airway seal of 50 mL for both sizes of ETC. Smaller filling volumes for the proximal balloon will result in lower cuff pressures and may thus reduce mucosal injury. Piriform sinus rupture also is reported in the literature [60]. The reports on the hemodynamic changes attributed to the insertion of the ETC are controversial [44,49,58]. Oczenski et al [58] find a significantly higher hemodynamic and catecholamine stress response after insertion of the ETC, probably because of the high proximal balloon pressure, compared with the LMA and ETT. Unlike their findings, Gaitini et al [44] and Urtubia et al [49] do not observe tachycardia or elevated blood pressures; however, catecholamine levels were not checked in these studies.
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Summary The ETC is an easily inserted, double-lumen/double-balloon supraglottic airway device. The major indication of the ETC is as a back-up device for airway management. It is an excellent option for rescue ventilation in both in- and out-of-the-hospital environments and in situations of difficult ventilation and intubation. It is useful especially in patients with massive airway bleeding or limited access to the airway and in patients in whom neck movement is contraindicated. Continued airway management with an ETC that has been placed is a reasonable option in many cases. Having thus secured the airway, it may not be necessary to abort the anesthetic or to continue with further airway management efforts. In order to avoid serious trauma to the esophagus or airway, redesigning the ETC using a softer material for the tube is advisable.
References [1] Don Michael TA, Lambert EH, Mehran A. Mouth-to-lung airway for cardiac resuscitation. Lancet 1968;2:1329 – 32. [2] Meislin HW. The esophageal obturator airway: a study of respiratory effectiveness. Ann Emerg Med 1980;9:54 – 9. [3] Smith JP, Bodui BI, Seifkin A, et al. The esophageal obturator airway: a review. JAMA 1983; 250:1081 – 4. [4] Bryson TK, Benumof JL, Ward CF. The esophageal obturator airway: a clinical comparison of ventilation with a mask and oropharyngeal airway. Chest 1978;74:537 – 9. [5] Hammargren Y, Clinton JE, Ruiz E. A standard comparison of esophageal obturator airway and endotracheal tube ventilation in cardiac arrest. Ann Emerg Med 1985;14:953 – 8. [6] Auerbach P, Geehr E. Inadequate oxygenation and ventilation using the EGTA in the prehospital setting. JAMA 1983;250:3067 – 71. [7] Bass RR, Allison EJ, Hunt RC. The esophageal obturator airway: a reassessment of use by paramedics. Ann Emerg Med 1982;11:358 – 60. [8] Gertler JP, Cameron DE, Shea K, et al. The esophageal obturator airway: obturator or obtundator? J Trauma 1985;25:424 – 6. [9] Yancey W, Wears R, Kamajian G, et al. Unrecognized tracheal intubation: a complication of the esophageal obturator airway. Ann Emerg Med 1980;9:18 – 20. [10] Schooll DG, Tsai SH. Esophageal perforation following the use of the esophageal obturator airway. Radiology 1977;122:315 – 6. [11] Johnson KR, Genovesi MG, Lassar KH. Esophageal obturator airway: use and complications. JASEP 1976;5:36 – 9. [12] Crippen D, Olvey S, Graffis R. Gastric rupture: an esophageal obturator airway complication. Ann Emerg Med 1981;10:370 – 3. [13] Frass M, Frenzer R, Zahler J. Respiratory tube or airway, U.S. patent no. 4, 688, 568. [14] Frass M, Frenzer R, Rauscha A, et al. Evaluation of esophageal combitube in cardiopulmonary resuscitation. Crit Care Med 1987;15:609 – 11. [15] Atheron GL, Johnson JC. Ability of paramedics to use the Combitube in prehospital cardiac arrest. Ann Emerg Med 1993;22:1262 – 8. [16] Urtubia R, Aguila C. Combitube: a new proposal for a confusing nomenclature. Anesth Analg 1999;89:803. [17] Yardy N, Hancox D, Strang T. A comparison of two airway aids for emergency use by unskilled personnel. The Combitube and the laryngeal mask. Anaesthesia 1999;54:181 – 3.
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[18] Walz R, Davis S, Panning B. Is the Combitube a useful emergency airway device for anesthesiologists? Anesth Analg 1999;88:233. [19] Lipp MD, Jaechnichen G, Golecki N, et al. Microbiological, microstructure and material science examination of reprocessed Combitubes after multiple use. Anesth Analg 2000;91:693 – 7. [20] Bishop M, Kharasch ED. Is the Combitube a useful emergency device for anesthesiologists? Anesth Analg 1998;86:1141 – 2. [21] Wafai Y, Salem MR, Baraka A, et al. Effectiveness of the self-inflating bulb for verification of proper placement of the Eophageal Tracheal Combitube. Anesth Analg 1995;80: 122 – 6. [22] Salem MR, Wafai Y, Baraka A, et al. Efficacy of the self-inflating bulb in verification of the proper placement of the Esophageal Tracheal Combitube. Anesthesiology 1993;79:A271. [23] Rumball CJ, MacDonald D. The PTL, Combitube laryngeal mask, and oral airway: a randomized prehospital comparative study of ventilatory device effectiveness and cost-effectiveness in 470 cases of cardiorespiratory arrest. Prehosp Emerg Care 1997;1:1 – 10. [24] Tanigawa K, Shigematsu A. Choice of airway devices for 12,020 cases of nontraumatic cardiac arrest in Japan. Prehosp Emerg Care 1998;2:96 – 100. [25] Ochs M, Vilke GM, Chan TC, et al. Successful prehospital airway management by EMT-Ds using the Combitube. Prehosp Emerg Care 2000;4:333 – 7. [26] Kofler J, Sterz F, Hofbauer R, et al. Epinephrine application via an endotracheal airway and via the Combitube in esophageal position. Crit Care Med 2000;28:1445 – 9. [27] Frass M, Frenzer R, Zdrahal F, et al. The Esophageal Tracheal Combitube: preliminary results with a new airway for CPR. Ann Emerg Med 1987;16:768 – 72. [28] Frass M, Frenzer R, Rauscha F, et al. Ventilation with the esophageal tracheal combitube in cardiopulmonary resuscitation. Promptness and effectiveness. Chest 1988;93:781 – 4. [29] Frass M, Rodler S, Frenzer R, et al. Esophageal tracheal combitube, endotracheal airway, and mask: comparison of ventilatory pressure curves. J Trauma 1989;29:1476 – 9. [30] Staudinger T, Brugger S, Watschinger B, et al. Emergency intubation with the Combitube: comparison with the endotracheal airway. Ann Emerg Med 1993;22:1573 – 5. [31] Advanced Trauma Life Support. 6th edition. American College of Surgeons, Chicago, Ill. 1999. P. 67 – 8. [32] Blostein PA, Koestner AJ, Hoak S. Failed rapid sequence intubation in trauma patients: eophageal tracheal combitube is a useful adjunct. J Trauma 1999;44:534 – 7. [33] Calkins MC, Robinson TD. Combat trauma airway management: endotracheal intubation versus laryngeal mask airway versus Combitube by navy seal and reconnaissance combat corpsman. J Trauma 1999;46:927 – 32. [34] Davis DP, Ochs M, Hoyt DB, et al. The use of the combitube as a salvage device for paramedic in rapid-sequence intubation. Acad Emerg Med 2001;8:500. [35] American Society of Anesthesiologists Task Force on the Management of the Difficult Airway. Practice guidelines for management of the difficult airway. Anesthesiology 1993;78: 597 – 602. [36] American Heart Association. Combination esophageal-tracheal tube. Guidelines for cardiopulmonary resuscitation and emergency cardiac care: recommendations of the 1992 National Conference of the American Heart Association. JAMA 1992:268;2203. [37] Baskett PJF, Bossaert L, Carli P, et al. Guidelines for the advanced management of the airway and ventilation during resuscitation. Resuscitation 1996;31:201 – 30. [38] Gaitini LA, Vaida SJ, Fradis M, et al. Replacing the combitube by an endotracheal tube using a fibre-optic bronchoscope during spontaneous ventilation. J Laryngol Otol 1998;12:786 – 7. [39] Baraka A, Salem R. The Combitube oesophageal-tracheal double lumen airway for difficult intubation. Can J Anaesth 1993;40:1222 – 3. [40] Eichinger S, Schreiber W, Heinz T, et al. Airway management in a case of neck impalement: use of the oesophageal tracheal combitube airway. Br J Anaesth 1992;68:534 – 5. [41] Staudinger T, Tesinsky P, Klappacher G, et al. Combitube in two cases of difficult airway management. Eur J Anaesthesiol 1995;12:189 – 93.
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[42] Bigenzahn W, Pesau B, Frass M. Emergency ventilation using the Combitube in cases of difficult intubation. Eur Arch Otorhinolaryngol 1991;248:129 – 31. [43] Crosby ET, Cooper RM, Douglas MJ, et al. The unanticipated difficult airway with recommendations for management. Can J Anaesth 1998;45:757 – 76. [44] Gaitini LA, Vaida SJ, Mostafa S, et al. The combitube in elective surgery: a report of 200 cases. Anesthesiology 2001;94:79 – 82. [45] Kraft P, Ro¨ggla M, Fridrich P, et al. Bronchoscopy via a redesigned Combitube in the esophageal position. A clinical evaluation. Anesthesiology 1997;86:1041 – 5. [46] Ovassapian A, Liu S, Krejcie T. Fiberoptic tracheal intubation with Combitube in place. Anesth Analg 1993;76:S315. [47] Gaitini LA, Vaida SJ, Somri M, et al. Fiberoptic-guided airway exchange of the esophagealtracheal Combitube in spontaneously breathing versus mechanically ventilated patients. Anesth Analg 1999;88:193 – 6. [48] Mallick A, Quinn AC, Bodenham AR, et al. Use of the Combitube for airway maintenance during percutaneous dilatational tracheostomy. Anaesthesia 1998;53:249 – 55. [49] Urtubia RM, Aguila CM, Cumsille MA. Combitube: a study for proper use. Anesth Analg 2000; 90:958 – 62. [50] Hartmann T, Hoerauf KH, Benomof JL, et al. The oesophageal-tracheal Combitube small adult. An alternative airway for ventilatory support during gynecological laparoscopy. Anaesthesia 2000;55:670 – 5. [51] Hoerauf KH, Hartmann T, Acimovic S, et al. Waste gas exposure to sevoflurane and nitous oxide during anesthesia using the oesophageal-tracheal Combitube small adult. Br J Anaesth 2001;86: 124 – 6. [52] Frass M. The Combitube: esophageal/tracheal double lumen airway. In: Benumof JL, editor. Airway management—principles and practice. St. Louis: Mosby; 1996. p. 444 – 55. [53] Vaida S. The effectiveness of the Esophageal-Tracheal Combitube in mechanically ventilated patients undergoing laparoscopic cholecystectomy. Anesthesiaologie – Intensinmedidizin 1999; 34:S121. [54] Gaitini L, Vaida S, Somri M, et al. Airway pressure differences with the Combitube. E J Anesthesiol 2001;18(Suppl 21):A99. [55] Mercer MH, Gabbott DA. The influence of neck position on ventilation using the Combitube airway. Anaesthesia 1998;53:146 – 50. [56] Ve´zina D, Lessard MR, Bussie`res J, et al. Complications associated with the use of the Esophageal-Tracheal Combitube. Can J Anaesth 1998;45:76 – 80. [57] Klein H, Williamson M, Sue-Ling HM, et al. Esophageal rupture associated with the use of the Combitube. Anesth Analg 1997;85:937 – 9. [58] Oczenski W, Krenn H, Dahaba AA, et al. Complications following the use of the Combitube, tracheal tube and laryngeal mask airway. Anaesthesia 1999;54:1161 – 5. [59] Gaitini L, Vaida S, Somri M, et al. Minimal inflation volume for adeaquate filling of the Combitube Pharyngeal Balloon. Anesthesiology 2000;93:A-1318. [60] Richards CF. Piriform sinus perforation during Esophageal-Tracheal Combitube placement. J Emerg Med 1998;16:37 – 9.
The Esophageal-Tracheal Combitube Luis A. Gaitini, MD a,*, Sonia J. Vaida, MD a, Felice Agro, MD b a
Anesthesiology Department, Bnai-Zion Medical Center, Faculty of Medicine, Technion, 47 Colomb Street, POB 4940, 31048, Haifa, Israel b Anesthesiology Department, University School of Medicine, Campus BioMedico, Via Longoni 69 – 83 00155, Roma, Italy
History One of the most challenging tasks in cardiopulmonary resuscitation (CPR) or difficult intubation is to provide rapidly a patent airway to facilitate adequate ventilation. Endotracheal intubation is the gold standard for airway management; however, on some occasions, it may be difficult or impossible even for skilled anesthesiologists. Many alternative airway devices have been used in emergency before the Esophageal-Tracheal Combitube (ETC). The esophageal obturator airway (EOA) [1] was first described in 1968 by Don Michael et al as an alternative to the endotracheal airway during emergency intubation. The main advantage of such a device is that direct laryngoscopy is not required and training in its use would therefore require less skill and medical input [2,3]. Nevertheless, it soon became apparent that considerable technical difficulties were associated with this device [4]. The main complications associated with the use of the EOA were leakage of air around the facemask resulting in inadequate ventilation [4,5], inadvertent or unrecognized tracheal placement [6 – 9], and esophageal or gastric ruptures [10 – 12]. The ETC was designed to overcome the limitations of the EOA, effectively combining the functions of the EOA and a traditional endotracheal tube (ETT). It was invented and brought into clinical use in 1987 by Frass in cooperation with Frenzer and Zahler of Moedling, Austria, and Vienna, Austria [13].
* Corresponding author. E-mail address: [email protected] (L.A. Gaitini, MD). 0889-8537/02/$ – see front matter D 2002, Elsevier Science (USA). All rights reserved. PII: S 0 8 8 9 - 8 5 3 7 ( 0 2 ) 0 0 0 2 1 - 4
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Functional anatomy The ETC (Tyco-Kendall, Sheridan, Mansfield, MA) is a disposable polyvinyl chloride double lumen supraglottic airway device with two inflatable balloons (Fig. 1). The two lumens are divided by a partition. Ventilation is possible with either tracheal or esophageal intubation, but is usually enters the esophagus in more than 95% of cases [14,15]. The pharyngeal lumen [16] has a blocked distal end and a blue proximal end with a standard 15-mm connector. This lumen communicates with the airway by eight oval-shaped holes (7 3 mm) positioned at the level of the lower pharynx.
Fig. 1. The Esophageal-Tracheal Combitube.
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The tracheal lumen has a shorter clear proximal portion with a standard 15-mm connector and it is open at the distal end. A black ring around both lumens is intended to be a depth marker, and, when placed between incisors or the alveolar ridges, results in an incisor to ETC tip distance of 22 mm. An oropharyngeal balloon proximal to the pharyngeal perforations of the esophageal lumen serves to seal the oral and nasal cavity, and a distal balloon situated proximal to the distal opening of the tracheal lumen serves as a seal of either the esophagus or the trachea, depending on which of these the ETC has been sited. The ETC is available in two sizes, the small adult ETC 37 F, recommended for patients with a height between 4 and 6 feet (approximately 120 to 180 cm), and the large adult ETC 41 F, for patients taller than 6 feet (approximately 180 cm), with an overlap between both sizes [17]. Walz et al [18] report the successful use of the ETC 37 F in patients up to 198 cm height, recommending its use independent of an upper limit height. The ETC 37 F is prepackaged with a large syringe, predrawn to 85 mL (41 F: 100 ml), and a small syringe, predrawn to 12 mL (41 F: 15 ml). The large syringe is color-coded to ensure inflation of the oropharyngeal proximal balloon via the valve with the blue pilot balloon. The kit also provides a 10 F (41 F: 12 F) suction catheter as well as a deflection elbow to avoid soiling of the rescuer by gastric contents. The ETC is delivered in a hard tray, as a roll-up kit (both kits containing all accessories), or as a single kit (containing the ETC only). Although the ETC was initially designed as a disposable single-use device, according to a recent publication the microbiological, microstructure, and material science examination prove that reprocessing of multiple reused (four times) ETC is possible and safe [19].
Insertion The ETC is inserted blindly in a curved downward movement by grasping the back of the tongue and jaw between thumb and forefinger and lifting the jaw until the printed ringmarks lie between the teeth or alveolar ridges in edentulous patients. The head remains preferably in neutral position; some clinicians prefer to extend the head or use a small cushion. The typical sniffing position should be avoided. The ETC should be introduced by a gentle movement, never using force (Fig. 2). Next the proximal balloon of the 37 F and 41 F ETC is inflated with 85 mL and 100 mL of air, respectively. During inflation, the tube moves slightly out of the patient’s mouth. Then the distal balloon is inflated with 10 to 12 mL and 10 to 15 mL of air, respectively. The ‘‘big’’ syringe’’ should be used to inflate the ‘‘big blue balloon’’ first. To avoid overinflation of the distal balloon and subsequent esophageal trauma, remember BBBB (Big Blue Balloon Before) (Fig. 3).
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Fig. 2. Insertion technique of the Esophagel-Tracheal Combitube.
The proximal balloon when inflated is pressed against the base of the tongue and closes the soft palate, thereby sealing the hypopharynx against the oral and nasal cavities. The ETC is correctly positioned when the ventral part of the proximal balloon reaches the posterior part of the hard palate, thus ensuring a strong anchoring, which is helpful during ventilation. Although the ETC may be inserted blindly, laryngoscopy may be performed to enhance placement of the device [20].
Fig. 3. Inflation of the balloons of the Esophagel-Tracheal Combitube.
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To facilitate insertion, it is recommended to bend the ETC to a 90° angle for several seconds at the point between the proximal and distal balloon. This accentuation of the curvature alleviates insertion along the tongue (‘‘Lipp maneuver’’) (M. Lipp, personal communication 1996). The most common cause of difficulty of ventilating the patient via the ‘‘paryngeal lumen,’’ despite appropriate intraesophageal placement, is that the ETC is inserted too deeply [20]. When the ETC is inserted too deeply, the ventilation pharyngeal holes may be inside the esophagus and unable to have gaseous communication with the larynx. When difficulty with ventilation is encountered after an eventful ETC insertion,the recommendation is to deflate both balloons, pull the ETC out 1 to 2 cm, reinflate the balloons, and try instituting ventilation again.
Placement confirmation After insertion of the ETC, a correct identification of the distal lumen as being intraesophageal or intratracheal is required. Because of the high probability that the tube will be placed into the esophagus, after blind insertion, test ventilation is recommended through the longer blue tube leading to the esophageal lumen. Air passes into the pharynx and from there over the epiglottis into the trachea because the mouth, nose, and esophagus are blocked by the balloons (Fig. 4). Auscultation of breath sounds in the absence of gastric insufflation confirms adequate ventilation when the ETC is in the esophagus. Ventilation is then continued through this lumen. In this position, gastric contents can be suctioned through the other unused ‘‘tracheal’’ lumen. If no breath sounds are heard over
Fig. 4. The Esophagel-Tracheal Combitube in esophageal position.
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Fig. 5. The Esophagel-Tracheal Combitube in tracheal position.
the lungs in the presence of gastric insufflation, the ETC has been placed into the trachea (Fig. 5). Without changing the position of the ETC, ventilation is changed to the shorter clear tube leading to the tracheal lumen and position is again confirmed by auscultation. In addition, capnography is mandatory to confirm adequate ventilation. A selfinflating bulb can quickly and reliably identify esophageal or tracheal placement of the ETC and facilitate proper selection of the correct ventilatory lumen [21,22].
Uses and indications Cardiopulmonary resuscitation Out-of-hospital The ETC is used mainly for airway control in emergencies when establishment of an ETT is not immediately possible [23,24]. The double-lumen/double-balloon design of the ETC permits rapid institution of rescue ventilation after blind insertion into either esophagus or trachea and affords protection from regurgitation or aspiration. In a prospective study, Atherton and Johnson [15] investigated the ability of paramedics in a nonurban emergency medical services system to use the ETC in prehospital cardiac arrest patients. The ETC was successfully inserted in 71% of cases when used as a first-line airway adjunct and 64% of the time in patients who could not be intubated with an ETT using direct laryngoscopy. A follow-up study of the paramedics conducted 15 months later demonstrated inadequate skill retention.
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In a series of 470 patients reported by Rumball and MacDonald [23], the ETC was rated best when comparing the device with the pharyngeal tracheal lumen airway (PTLA), the laryngeal mask airway (LMA), and the oral airway (OA)/ mask when used in conjunction with a bag-valve device by emergency medical technicians (EMTs) during cardiorespiratory arrest. Success rate of insertion and ventilation was significantly higher with the ETC (86% successful insertion rate) despite the fact that some of the EMTs had been previously trained to use the LMA in the operating room. In a retrospective study of 12,020 cases of nontraumatic cardiac arrest, Tanigawa and Shigematsu [24] find the ETC to have a better first attempt insertion rate (82.4%) than either the esophageal gastric tube airway (EGTA) or the LMA. Also, success rates for ventilation and for insertion are significantly higher with the ETC. In a recent study [25], emergency medical technicians – defibrillation (EMTDs) were trained to use the ETC in prehosopital environment in a 18-month prospective field study. ETC insertions were attempted in 195 prehospital patients in cardiopulmonary arrest with an overall successful intubation rate of 79%. When necessary during CPR, epinephrine can be applied via the pharyngeal lumen of the ETC in a ten fold higher dosage with similar effects on plasma epinephrine levels and hemodynamic variables as with the endotracheal administration [26]. ETT remains the gold standard for ventilation and protection for aspiration, but the ETC is a viable choice with a high success rate when used as an initial airway by trained paramedics. While insertion of the ETC requires a lesser degree of skill than does ETT, it is mandatory that continuing education and testing reinforce the requisite skills for the successful use of the ETC. In-hospital CPR Several studies prove the effectiveness of the ETC in ventilating patients during CPR in intensive care settings [14,27,28]. In a 1987 report [27], 21 patients requiring CPR were intubated with the ETC. Acceptable blood gas results were achieved in all patients, despite the fact that three patients had vomited prior to introduction of the ETC. These results encouraged further studies into the use of the ETC during CPR. Frass et al [14] checked the effectiveness of ventilation in 31 patients requiring CPR after cardiac arrest calls, either in intensive care or in a general hospital ward setting. The first part of the study examined the adequacy of ventilation by ETC and a reservoir bag, using an estimated inspired oxygen concentration of 40%. The second part compared the efficiency of ventilation with the ETC with conventional ETT in a group of 15 mechanically ventilated patients. Patients ventilated using the ETC were reported to have significantly higher mean arterial oxygen tensions than those in the ETT group. In post mortem examinations of patients who died within 24 hours after CPR, there was no evidence of pulmonary aspiration.
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In another study [28], the promptness and effectiveness of ventilation using the ETC for airway management during CPR was investigated. The time required for correct placement was significantly shorter in the ETC group (27.3 ± 8.4 s) compared with the ETT group (39.7 ± 10.0 s), despite the fact that more time was required for balloon inflation with the ETC. The differences in total intubation time were thought to be partially explained by the fact that direct laryngoscopy is unnecessary to position the ETC correctly. Ventilation via the ETC was demonstrated to produce higher mean arterial oxygen tensions than ventilation via the tracheal tube. The postulated explanation for the higher PaO2 in the patients ventilated with an ETC is a prolonged respiratory flow time and an increase in expiratory resistance resulting in a small degree of auto-PEEP (2 cm H2O). Additionally, the vocal cords are not by-passed with the ETC compared with the situation when an ETT is used [29]. Staudinger et al evaluated [30] the safety and effectiveness of the ETC as used by intensive care nurses under medical supervision compared with endotracheal intubation performed by intensive care physicians during CPR. Intubation time was shorter for the ETC. Blood gases for each device showed comparable results; the arterial oxygen tension was slightly higher during ventilation with the ETC. The study suggests that the ETC as used by intensive care nurses is as effective as the endotracheal airway by intensivists during CPR. Trauma Despite the fact that the Advanced Trauma Life Support [31] protocol does not include the ETC as an alternative airway device in cases of failed intubation, the use of the ETC in trauma is described in several studies [32 –34]. Flight nurses are trained in the use of ETC by mannequin simulation, videotape review, and didactic session. ETC insertion is attempted after failure of two or more attempts at orotracheal rapid-sequence induction and was successful in all ten patients in whom it was attempted. Seven patients requiring ETC had mandible fractures [32]. In a prospective study, Calkins and Robinson [33] compare the ability of Special Operations Corpsmen to use the ETT, LMA, or ETC under simulated combat conditions, concluding that, on occasion, an advanced combat casualty care provider may be unable to place an ETT; the LMA and ETC are useful alternatives in this situation. A recent study reports the effectiveness of ETC as an adjunct for paramedic rapid sequence induction when orotracheal intubation is unsuccessful, recommending increased minute ventilation to avoid hypercapnia [34]. ETC was successful in 96.7% of intubation attempts. Difficult airways The American Society of Anesthesiologists Task Force on Management of the Difficult Airway recommends use of the ETC in addition to the LMA, jet
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ventilation, and surgical airway when intubation problems occur in patients with a previously unrecognized difficult airway, especially in a ‘‘cannot ventilate, cannot intubate’’ situation [35]. Its use for difficult airway management also has been included in the ‘‘Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiac Care’’ of the American Heart Association [36]. Furthermore, the ETC was included in the ‘‘Guidelines of the European Resuscitation Council’’ in 1996 [37]. There are several reports of the effective use of the ETC in cases of difficult or failed endotracheal intubation [38 – 43]. Although it is possible to maintain an airway with the ETC [44], endotracheal intubation remains the preferred method for definitive or protracted securing of the airway. Therefore, exchange of the ETC with an ETT may often be desirable in continued management of the airway, and several techniques of ETC – ETT exchange under fiberoptic vision are described [45 – 47]. Kraft et al [45] redesigned the ETC by replacing its two proximal perforations with a larger hole, consequently making possible the passage of a fiberoptic bronchoscope through the ETC. In this technique, a guidewire is then passed through the fiberscope into the trachea, the ETC and fiberscope scope removed, and an ETT passed over the guidewire which has been left in place. This technique requires brief abdication of the airway after withdrawal of the fiberscope and ETC and until passage of an ETT over the guide wire. Ovassapian et al [46] inserted the fiberoptic bronchoscope orally alongside the ETC while the patients were paralyzed and ventilated, with an 85% success rate. Gaitini et al [47] describe a successful airway exchanges without interruption of airway control or ventilation, through nasal fiberoptic intubations in 18 spontaneously breathing patients and in 15 patients during controlled ventilation. The study suggests that spontaneous ventilation significantly improves the effectiveness of the technique, making identification and exposure of the epiglottis and the larynx easier. This airway exchange methods can be of value in situations demanding definitive airway control (eg, specific surgical procedures), when prolonged mechanical ventilation is needed, and for suctioning the trachea when necessary. In addition, the ETC is successfully used for maintenance of ventilation during percutaneous dilatational tracheostomy [48]. Elective surgery The ETC has been used and studied during routine general anesthetics. [18,43,48 –50] A recently published series of 200 cases proves the safety and effectiveness of the ETC in primary airway management for routine surgery with both mechanical and spontaneous ventilation of patients. In 97% of patients, excellent oxygenation, ventilation, respiratory mechanics, and hemodynamic stability are achieved. The duration of surgery is between 15 and 155 min. These investigators suggest that continued airway management with an ETC that has been placed is a reasonable option in many cases. Having thus secured the
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airway, it may not be necessary to abort the anesthetic or to continue with further airway management efforts [44]. In series of 25 patients undergoing elective surgery, Urtubia et al [49] report that ventilation is performed easily without signs of gastric insufflation. Recently, Hartmann et al [50] published a study on the ETC 37 F as an alternative airway for ventilatory support during gynecological laparoscopy. Airway management was performed with either ETC or tracheal intubation. Time for the ETC insertion while using a laryngoscope was 16 seconds. Peak airway pressures with the ETC were 25 ± 5 cm H2O. An airtight seal was obtained using air volumes of 55 ± 13 mL (proximal balloon) and 10 ± 1 mL (distal balloon). Another study by Hoerauf et al [51] dealing with patients undergoing elective surgery investigates waste gas exposure to sevoflurane and nitrous oxide during anesthesia using the ETC 37 F. Concentrations of sevoflurane and nitrous oxide are measured at the patient’s mouth and within the anesthesiologist’s breathing zone using direct spectrometer analysis. Results show that the ETC provides a seal as good as an ETT. Walz et al [18] report adequate oxygenation and ventilation in 104 patients undergoing automatic implantible cardioverter defibrillation implantation during a period of 45 to 360 min.
Advantages The ETC provides rapid and easy airway control without the need for direct laryngoscopy and neck or head movement with firm fixation of the device after inflation of the proximal balloon [52]. It works equally well in tracheal or esophageal position. The ETC can be placed by anesthesiologists with relatively little formal training [20] and by relatively inexperienced personnel. [15,25,30]. The ETC minimizes the danger of pulmonary aspiration [14,49]. The design of the proximal balloon and the distal balloon protects the airway from esophageal and gastric contents, blood, and debris [14]. In the esophageal position, the unused tracheal lumen also helps to decrease the likelihood of aspiration by immediate decompression of the stomach and by provision of a route for evacuation of gastric fluid. Urtubia et al [49] studied the protection offered by the ETC against aspiration by administrating methylene blue orally before anesthesia to 25 patients. There were no traces of methylene blue in the hypopharynx as investigated by direct laryngoscopy performed before the insertion of the ETC and after its removal. In 25 cases of laparoscopic cholecystectomy with mechanical ventilation using the ETC, no gastric insufflation could be observed in the beginning or end of surgery, as recorded by video films [53]. Relatively high airway pressure can be obtained with mechanical ventilation [44,50]; however, because of the design of the ETC, the delivered oropharyngeal pressure (presumably a reflection of intratracheal pressure) is
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significantly lower than the pressure measured at the anesthesia breathing system [54].
Disadvantages, contraindications, and complications Disadvantages include the impossibility of suctioning the trachea in esophageal position and possible esophageal damage. The contraindications to using the ETC include height less than four feet, intact gag reflexes, esophageal abnormalities, known ingestion of caustic substances, and glottic and supraglottic airway obstruction. The ETC cannot be recommended for use in patients whose necks are already immobilized in rigid cervical collars; however, it may be inserted successfully with a rigid collar in place, after temporary removal of the anterior part of the collar while the head is maintained with in-line mobilization [55]. There are few reports of esophageal perforation associated with the use of the ETC [24,56,57]. In a series of 1130 prehospital cardiac arrests managed with the ETC [56], eight patients presented with subcutaneous emphysema. Five of these eight patients had autopsies performed and two of these revealed longitudinal transparietal tears of the anterior wall of the esophagus. In these cases, the distal balloon was over-inflated with 20 to 40 mL of air (instead of 10 to15 mL with the ETC 37 F or 15 mL with the ETC 41). The potential for injury to the pharyngeal mucosa from excessive pressure exerted by the proximal balloon of the ETC is described [55,58]. A large inflation volume of the proximal balloon may tear the mucosa by stretching it, especially the posterior pharyngeal wall, [58] causing postoperative sore throat or dysphagia [55,58]. When the pressure of the proximal balloon transmitted to the pharyngeal mucosa exceeds capillary perfusion pressure of the mucosa tissue, ischemia is possible. The reported incidence of postoperative sore throat after use of the ETC varies from 25% to 48% [38,58]. Recent studies indicate that the proximal balloon fill volume needed to achieve an airway seal is substantially less than that recommended by the manufacturer [49,59].The proximal balloon inflation volume for ETC 37 F to prevent an air leak was estimated at 40 to 85 mL of air [49]. Gaitini et al [59] find a minimal inflation volume for an adequate airway seal of 50 mL for both sizes of ETC. Smaller filling volumes for the proximal balloon will result in lower cuff pressures and may thus reduce mucosal injury. Piriform sinus rupture also is reported in the literature [60]. The reports on the hemodynamic changes attributed to the insertion of the ETC are controversial [44,49,58]. Oczenski et al [58] find a significantly higher hemodynamic and catecholamine stress response after insertion of the ETC, probably because of the high proximal balloon pressure, compared with the LMA and ETT. Unlike their findings, Gaitini et al [44] and Urtubia et al [49] do not observe tachycardia or elevated blood pressures; however, catecholamine levels were not checked in these studies.
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Summary The ETC is an easily inserted, double-lumen/double-balloon supraglottic airway device. The major indication of the ETC is as a back-up device for airway management. It is an excellent option for rescue ventilation in both in- and out-of-the-hospital environments and in situations of difficult ventilation and intubation. It is useful especially in patients with massive airway bleeding or limited access to the airway and in patients in whom neck movement is contraindicated. Continued airway management with an ETC that has been placed is a reasonable option in many cases. Having thus secured the airway, it may not be necessary to abort the anesthetic or to continue with further airway management efforts. In order to avoid serious trauma to the esophagus or airway, redesigning the ETC using a softer material for the tube is advisable.
References [1] Don Michael TA, Lambert EH, Mehran A. Mouth-to-lung airway for cardiac resuscitation. Lancet 1968;2:1329 – 32. [2] Meislin HW. The esophageal obturator airway: a study of respiratory effectiveness. Ann Emerg Med 1980;9:54 – 9. [3] Smith JP, Bodui BI, Seifkin A, et al. The esophageal obturator airway: a review. JAMA 1983; 250:1081 – 4. [4] Bryson TK, Benumof JL, Ward CF. The esophageal obturator airway: a clinical comparison of ventilation with a mask and oropharyngeal airway. Chest 1978;74:537 – 9. [5] Hammargren Y, Clinton JE, Ruiz E. A standard comparison of esophageal obturator airway and endotracheal tube ventilation in cardiac arrest. Ann Emerg Med 1985;14:953 – 8. [6] Auerbach P, Geehr E. Inadequate oxygenation and ventilation using the EGTA in the prehospital setting. JAMA 1983;250:3067 – 71. [7] Bass RR, Allison EJ, Hunt RC. The esophageal obturator airway: a reassessment of use by paramedics. Ann Emerg Med 1982;11:358 – 60. [8] Gertler JP, Cameron DE, Shea K, et al. The esophageal obturator airway: obturator or obtundator? J Trauma 1985;25:424 – 6. [9] Yancey W, Wears R, Kamajian G, et al. Unrecognized tracheal intubation: a complication of the esophageal obturator airway. Ann Emerg Med 1980;9:18 – 20. [10] Schooll DG, Tsai SH. Esophageal perforation following the use of the esophageal obturator airway. Radiology 1977;122:315 – 6. [11] Johnson KR, Genovesi MG, Lassar KH. Esophageal obturator airway: use and complications. JASEP 1976;5:36 – 9. [12] Crippen D, Olvey S, Graffis R. Gastric rupture: an esophageal obturator airway complication. Ann Emerg Med 1981;10:370 – 3. [13] Frass M, Frenzer R, Zahler J. Respiratory tube or airway, U.S. patent no. 4, 688, 568. [14] Frass M, Frenzer R, Rauscha A, et al. Evaluation of esophageal combitube in cardiopulmonary resuscitation. Crit Care Med 1987;15:609 – 11. [15] Atheron GL, Johnson JC. Ability of paramedics to use the Combitube in prehospital cardiac arrest. Ann Emerg Med 1993;22:1262 – 8. [16] Urtubia R, Aguila C. Combitube: a new proposal for a confusing nomenclature. Anesth Analg 1999;89:803. [17] Yardy N, Hancox D, Strang T. A comparison of two airway aids for emergency use by unskilled personnel. The Combitube and the laryngeal mask. Anaesthesia 1999;54:181 – 3.
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[18] Walz R, Davis S, Panning B. Is the Combitube a useful emergency airway device for anesthesiologists? Anesth Analg 1999;88:233. [19] Lipp MD, Jaechnichen G, Golecki N, et al. Microbiological, microstructure and material science examination of reprocessed Combitubes after multiple use. Anesth Analg 2000;91:693 – 7. [20] Bishop M, Kharasch ED. Is the Combitube a useful emergency device for anesthesiologists? Anesth Analg 1998;86:1141 – 2. [21] Wafai Y, Salem MR, Baraka A, et al. Effectiveness of the self-inflating bulb for verification of proper placement of the Eophageal Tracheal Combitube. Anesth Analg 1995;80: 122 – 6. [22] Salem MR, Wafai Y, Baraka A, et al. Efficacy of the self-inflating bulb in verification of the proper placement of the Esophageal Tracheal Combitube. Anesthesiology 1993;79:A271. [23] Rumball CJ, MacDonald D. The PTL, Combitube laryngeal mask, and oral airway: a randomized prehospital comparative study of ventilatory device effectiveness and cost-effectiveness in 470 cases of cardiorespiratory arrest. Prehosp Emerg Care 1997;1:1 – 10. [24] Tanigawa K, Shigematsu A. Choice of airway devices for 12,020 cases of nontraumatic cardiac arrest in Japan. Prehosp Emerg Care 1998;2:96 – 100. [25] Ochs M, Vilke GM, Chan TC, et al. Successful prehospital airway management by EMT-Ds using the Combitube. Prehosp Emerg Care 2000;4:333 – 7. [26] Kofler J, Sterz F, Hofbauer R, et al. Epinephrine application via an endotracheal airway and via the Combitube in esophageal position. Crit Care Med 2000;28:1445 – 9. [27] Frass M, Frenzer R, Zdrahal F, et al. The Esophageal Tracheal Combitube: preliminary results with a new airway for CPR. Ann Emerg Med 1987;16:768 – 72. [28] Frass M, Frenzer R, Rauscha F, et al. Ventilation with the esophageal tracheal combitube in cardiopulmonary resuscitation. Promptness and effectiveness. Chest 1988;93:781 – 4. [29] Frass M, Rodler S, Frenzer R, et al. Esophageal tracheal combitube, endotracheal airway, and mask: comparison of ventilatory pressure curves. J Trauma 1989;29:1476 – 9. [30] Staudinger T, Brugger S, Watschinger B, et al. Emergency intubation with the Combitube: comparison with the endotracheal airway. Ann Emerg Med 1993;22:1573 – 5. [31] Advanced Trauma Life Support. 6th edition. American College of Surgeons, Chicago, Ill. 1999. P. 67 – 8. [32] Blostein PA, Koestner AJ, Hoak S. Failed rapid sequence intubation in trauma patients: eophageal tracheal combitube is a useful adjunct. J Trauma 1999;44:534 – 7. [33] Calkins MC, Robinson TD. Combat trauma airway management: endotracheal intubation versus laryngeal mask airway versus Combitube by navy seal and reconnaissance combat corpsman. J Trauma 1999;46:927 – 32. [34] Davis DP, Ochs M, Hoyt DB, et al. The use of the combitube as a salvage device for paramedic in rapid-sequence intubation. Acad Emerg Med 2001;8:500. [35] American Society of Anesthesiologists Task Force on the Management of the Difficult Airway. Practice guidelines for management of the difficult airway. Anesthesiology 1993;78: 597 – 602. [36] American Heart Association. Combination esophageal-tracheal tube. Guidelines for cardiopulmonary resuscitation and emergency cardiac care: recommendations of the 1992 National Conference of the American Heart Association. JAMA 1992:268;2203. [37] Baskett PJF, Bossaert L, Carli P, et al. Guidelines for the advanced management of the airway and ventilation during resuscitation. Resuscitation 1996;31:201 – 30. [38] Gaitini LA, Vaida SJ, Fradis M, et al. Replacing the combitube by an endotracheal tube using a fibre-optic bronchoscope during spontaneous ventilation. J Laryngol Otol 1998;12:786 – 7. [39] Baraka A, Salem R. The Combitube oesophageal-tracheal double lumen airway for difficult intubation. Can J Anaesth 1993;40:1222 – 3. [40] Eichinger S, Schreiber W, Heinz T, et al. Airway management in a case of neck impalement: use of the oesophageal tracheal combitube airway. Br J Anaesth 1992;68:534 – 5. [41] Staudinger T, Tesinsky P, Klappacher G, et al. Combitube in two cases of difficult airway management. Eur J Anaesthesiol 1995;12:189 – 93.
906
L.A. Gaitini et al. / Anesthesiology Clin N Am 20 (2002) 893–906
[42] Bigenzahn W, Pesau B, Frass M. Emergency ventilation using the Combitube in cases of difficult intubation. Eur Arch Otorhinolaryngol 1991;248:129 – 31. [43] Crosby ET, Cooper RM, Douglas MJ, et al. The unanticipated difficult airway with recommendations for management. Can J Anaesth 1998;45:757 – 76. [44] Gaitini LA, Vaida SJ, Mostafa S, et al. The combitube in elective surgery: a report of 200 cases. Anesthesiology 2001;94:79 – 82. [45] Kraft P, Ro¨ggla M, Fridrich P, et al. Bronchoscopy via a redesigned Combitube in the esophageal position. A clinical evaluation. Anesthesiology 1997;86:1041 – 5. [46] Ovassapian A, Liu S, Krejcie T. Fiberoptic tracheal intubation with Combitube in place. Anesth Analg 1993;76:S315. [47] Gaitini LA, Vaida SJ, Somri M, et al. Fiberoptic-guided airway exchange of the esophagealtracheal Combitube in spontaneously breathing versus mechanically ventilated patients. Anesth Analg 1999;88:193 – 6. [48] Mallick A, Quinn AC, Bodenham AR, et al. Use of the Combitube for airway maintenance during percutaneous dilatational tracheostomy. Anaesthesia 1998;53:249 – 55. [49] Urtubia RM, Aguila CM, Cumsille MA. Combitube: a study for proper use. Anesth Analg 2000; 90:958 – 62. [50] Hartmann T, Hoerauf KH, Benomof JL, et al. The oesophageal-tracheal Combitube small adult. An alternative airway for ventilatory support during gynecological laparoscopy. Anaesthesia 2000;55:670 – 5. [51] Hoerauf KH, Hartmann T, Acimovic S, et al. Waste gas exposure to sevoflurane and nitous oxide during anesthesia using the oesophageal-tracheal Combitube small adult. Br J Anaesth 2001;86: 124 – 6. [52] Frass M. The Combitube: esophageal/tracheal double lumen airway. In: Benumof JL, editor. Airway management—principles and practice. St. Louis: Mosby; 1996. p. 444 – 55. [53] Vaida S. The effectiveness of the Esophageal-Tracheal Combitube in mechanically ventilated patients undergoing laparoscopic cholecystectomy. Anesthesiaologie – Intensinmedidizin 1999; 34:S121. [54] Gaitini L, Vaida S, Somri M, et al. Airway pressure differences with the Combitube. E J Anesthesiol 2001;18(Suppl 21):A99. [55] Mercer MH, Gabbott DA. The influence of neck position on ventilation using the Combitube airway. Anaesthesia 1998;53:146 – 50. [56] Ve´zina D, Lessard MR, Bussie`res J, et al. Complications associated with the use of the Esophageal-Tracheal Combitube. Can J Anaesth 1998;45:76 – 80. [57] Klein H, Williamson M, Sue-Ling HM, et al. Esophageal rupture associated with the use of the Combitube. Anesth Analg 1997;85:937 – 9. [58] Oczenski W, Krenn H, Dahaba AA, et al. Complications following the use of the Combitube, tracheal tube and laryngeal mask airway. Anaesthesia 1999;54:1161 – 5. [59] Gaitini L, Vaida S, Somri M, et al. Minimal inflation volume for adeaquate filling of the Combitube Pharyngeal Balloon. Anesthesiology 2000;93:A-1318. [60] Richards CF. Piriform sinus perforation during Esophageal-Tracheal Combitube placement. J Emerg Med 1998;16:37 – 9.