 |
|||||||||
|
The Esophageal Detector
Device Compiled by Tim Wolfe, M.D. PREHOSPITAL AND EMERGENT INTUBATION STUDIES
The oesophageal detector device. Assessment of a new method to distinguish oesophageal from tracheal intubation. Wee, MYK: Anaesthesia 1988;43:27-29. This is the first paper concerning the esophageal detector device (EDD). It reports its' use on 100 patients undergoing general anesthesia. These patients had an endotracheal tube (ETT) placed both in their trachea and in their esophagus. An anesthesiologist then used an EDD to determine where a randomly assigned tube was placed. Fifty-one esophageal tubes were immediately detected and 48 of 49 tracheal tubes were immediately detected. One of the 49 tracheal tubes showed a small amount of resistance to aspiration although the syringe did fill completely with air. This was interpreted as an equivocal result. This tracheal tube continued to give the anesthesiologist problems and when it was removed it was found to be almost completely occluded with secretions. Dr. Wee states that the observers found the esophageal detector device easy to use. There were no post-operative sequela. He concludes that "this device is a reliable, rapid, inexpensive, and easy to use method for the detection of esophageal intubation and its very low cost should make it readily available for all situations where tracheal intubation is carried out." A method of detecting oesophageal intubation or confirming tracheal intubation. O'Leary JJ, Pollard BJ, Ryan MJ: Anaesthesia and Intensive Care 1988;16:299-301. This study was conducted in the operating room on 50 patients undergoing elective intubation. All 25 esophageal tubes were immediately detected as were all 25 tracheal tubes, giving this device 100% accuracy. They recommend it as a valuable addition to one's intubation procedure. The oesophageal detector device: Successful use in children. Morten NS, Stuart JC, Thomson MF, Wee MYK: Anaesthesia 1989;44:523-524. This paper reports the use of an esophageal detector device on 20 pediatric patients, ages 5 to 10, undergoing general anesthesia in the operating room. These patients had an uncuffed endotracheal tube placed both in their trachea and in their esophagus. The device was 100% accurate in determining the location of the endotracheal tubes. The authors " recommend the routine use of this simple, inexpensive device wherever tracheal intubation is performed in both adults and children" and they " consider that it has the potential to become one of the routine safety checks to confirm endotracheal tube placement." Assessing the position of the tracheal tube. The reliability of different methods Anderson KH and Hald A: Anaesthesia 1989;44:984-985. These authors tested the EDD in 40 patients. A blinded observer was able to distinguish ETT location 100% of the time upon testing one tube. A total of 40 esophageal and 40 tracheal tubes were identified correctly. The Oesophageal detector device. A prospective trial on 100 patients. Williams KN, Nunn JF: Anaesthesia 1989;44:412-412. This paper reports the use of an esophageal detector device on 100 patients undergoing general anesthesia. A blinded anesthesiologist using an EDD was 100% accurate in determining the location of the endotracheal tube. Use of the oesophageal detector device in children under one year of age. Haynes SR, Morton NS: Anaesthesia 1990;45:1067-1069. This study used a modified esophageal detector device (a 5cc syringe rather than a 50 to 60 cc syringe) on pediatric patients less than one year old. They found the device unreliable in this age group. They hypothesized this failure was due to either air reflux from a hiatal hernias, a relatively non collapsible esophagus due to the ETT splinting it open, inadvertent intubation of the stomach with free air return, or a relatively immature/collapsible trachea which collapsed on aspiration. At this time the esophageal detector device is not recommended in children less than one year old. The Tubechek™ is only approved for use in patients 5 years or older. Evaluation of the esophageal detector device. Kolesar RE, Ananthanarayan C, Kapala D: Abstract in Anesthesiology 1990;73(3A):A417. These authors studied a self inflating bulb on 300 patients. They defined refill in less than 5 seconds as indicating tracheal placement. Of 149 tracheal tubes, delayed refill occured in 6 (all obese). Of 151 esophageal tubes, one filled with air in less than 5 seconds. This misidentified esophageal tube occurred in a patient who had gross stomach distention following prolonged manual ventilation. The oesophageal detector device. An assessment with uncuffed tubes in children. Wee MK, Walker AY: Anaesthesia 1991;46(10):869-871. This paper reports the use of an EDD on 100 pediatric patients, ages 1 to 10, undergoing general anesthesia. These patients had an uncuffed endotracheal tube placed both in their trachea and in their esophagus. A blinded anesthesiologist using an EDD was 100% accurate in determining tube location. The esophageal detector device. Does it work? Zaleski L, Abello D, Gold MI: Anesthesiology 1993;79(2):244-247. This study was conducted in an operating room on 500 electively intubated patients. The study was divided into three sections. In study number one, 300 patients were tracheally intubated. The esophageal detector device was then compared directly to capnography. Of these 300 patients, thirty were accidentally esophageally intubated. The capnograph and the EDD correctly identified all, demonstrating 100% correlation. In study number two, 100 patients were purposely esophageally intubated. Again, the EDD and capnography demonstrated 100% correlation. Patients were then tracheally intubated and re-comparison showed 100% correlation. In study number three, 51 patients were esophageally intubated and 49 patients were tracheally intubated in a blinded, randomized fashion. Capnography and esophageal detector device comparison demonstrated 100% correlation. There was a 6% incidence of delayed balloon filling in tracheal intubations (greater than 5 seconds but less than 30 seconds). They conclude that the esophageal detector device is a useful tool in the operating room and may be useful in the emergency department and in ambulances. Use of the self-inflating bulb for detecting esophageal intubation after "esophageal ventilation." Salem MR, Wafai Y, Baraka AB, et al: Anesth Analg 1993;77:1227-1231 This investigation was designed to test the efficacy of an esophageal detector device to properly detect esophageal intubation despite prior insufflation of air into the stomach. In 72 patients, both the trachea and esophagus were intubated. Three 300 -350 cc breaths were delivered through the esophageal tube in an attempt to simulate gastric air distention that occurs with bag mask ventilation. An esophageal detector device was then used and was found to be 100% accurate- detecting all 72 esophageal intubations immediately- despite air being in the stomach. They conclude this device may be "used in emergency rooms and ambulances" where "unlike capnography or colorimetric detection, the bulb functions equally in the patient with cardiac arrest and in the patient without cardiac arrest." The self-inflating bulb in detecting esophageal intubation: Effect of bulb size and technique used. Wafai Y, Salem MR, Czinn EA, Barbella J, Baraka A: Abstract in Anesthesiology 1993;79(3A):A496. The authors compared the accuracy of a self inflating bulb of 20cc to one of 75cc using two techniques: squeeze the bulb and then attach to the tube vs. attach to the tube then squeeze the bulb. 75 patients were studied. They found that the large bulb worked regardless of technique, but the small bulb only accurately identified esophageal intubation if it was squeezed and then applied. They recommend using a large bulb since it works regardless of technique. Efficacy of the self-inflating bulb in detecting esophageal intubation. Salem MR, Wafai Y, Joseph NJ, Baraka AB, Czinn EA: Anesthesiology 1994;80:42-48. This investigation was designed to test the efficacy of an esophageal detector device in the presence of a nasogastric tube and with endotracheal tube cuff deflation. 70 patients with nasogastric tubes were tested. The device was 100% effective in distinguishing tracheal from esophageal tubes. 60 patients were tested with the ETT cuffs deflated. Again the device was 100% accurate. The authors conclude that the device may be used " in the operating room ... as well as outside the operating room, in situations where tracheal intubation may be performed as an emergency measure." The esophageal detector device: An assessment of accuracy and ease of use by paramedics. Donahue PL: Anaesthesia 1994;49:863-865. This study attempted to determine whether paramedics unfamiliar with esophageal detector devices could use one to identify ETT location in the operating room. Forty intubations (19 esophageal and 21 tracheal) were correctly identified by the paramedics (100% accuracy). The self-inflating bulb for confirmation of tracheal intubation: Incidence and demography of false negatives. Wafai Y, Salem MR, Joseph NJ, Baraka A: Abstract in Anesthesiology 1994;81(3A):A1304. The authors compared two techniques of using the self inflating bulb on 2140 patients (elective and emergent intubations). Technique one consisted of compressing the bulb prior to attachment to the ETT, technique two compressed the bulb after attachment to the ETT. Technique 1 resulted in 4.5% incidence of false negative results (>4 seconds for bulb reinflation despite being in the trachea). Technique 2 resulted in 2.4% false negative results. 85.5% of the patients with false negative results were considered to be grossly obese (body mass index >35). The authors theorize that obese patients have decreased expiratory reserve volumes which leads to the bulbs inability to aspirate sufficient air. Effectiveness of the self-inflating bulb for verification of proper placement of the esophageal tracheal combitube. Wafai Y, Salem MR, Baraka A, Joseph NJ, Czinn EA, Paulissian R: Anesth Analg 1995;80:122-126. This study was designed to determine if an esophageal detector device could be used to determine the proper port to ventilate and properly position the Combitube™. 46 patients were studied and an algorithm designed that allowed users to properly locate and position the proximal combitube port for ventilation Evaluation of a prototype esophageal detection device. Marley CD, Eitel DR, Anderson TE, Murn AJ, Patterson GA: Acad Emerg Med 1995;2:503-507. This study was conducted in the operating room using a large self inflating bulb (100cc) type esophageal detector device on electively intubated patients. 45 esophageal tubes (100%) were immediately detected. 35 of 40 (87.5%) of tracheal tubes were correctly identified immediately, five reinflated slowly (>15 sec). Three of the five slow inflaters were found to be right mainstem intubations. The authors feel that absolutely proper technique be used so that delayed re-inflation does not result in unnecessary re-intubations. Efficacy of the Self-inflating bulb in verifying tracheal tube placement in children. Burnett YL, Brennan MP, Salem MR: Abstract in Anesth Analg 1995;80;S63. This study was conducted in the operating room on 216 patients aged 6 months to 20 years (ave 9 years). 248 intubation attempts were checked. 238 were tracheal, 10 esophageal. 10/10 esophageal tubes were correctly identified, 237/238 tracheal tubes were correctly identified. The single false negative was in a morbidly obese patient. Efficacy of the self-inflating bulb in confirming tracheal intubation in the morbidly obese. Lang DJ, Wafai Y, Salem MR, et al: Anesthesiology 1996;85:246-253. These authors sought to investigate the accuracy of the bulb EDD in morbidly obese patients (a group known to have a high incidence of false negative results) and to determine a mechanism for this high false negative rate. They entered 54 patients, and tested three techniques: squeeze bulb then apply to ETT and release, apply to ETT then squeeze bulb and release, give three small breaths, apply to ETT then squeeze bulb and release. They found the following false negative rates for each: 30%, 11%, 4%. Tracheal responses to the maneuvers were observed simultaneously by fiberoptic bronchoscopy. This observation revealed invagination of the tracheal wall as negative pressure occurred. They hypothesize that the mechanism is due to a reduced airway caliber in obese patients combined with a collapse of large airways resulting in reduced FRC and less air available for aspiration. Efficacy of the self-inflating bulb in differentiating esophageal from tracheal intubation in the parturient undergoing cesarean section. Baraka A, Khoury PJ, Siddik SS, et al: Anesth Analg 1997;84:533-7. These authors studied the accuracy of the bulb EDD in 40 parturients undergoing elective cesarean section. After intubation, and prior to any ventilation they found 21/40 rapid inflations (<4 sec) and 19/40 delayed inflations (4 -10 sec). This improved to 33/40 and 7/40 respectively after ventilation, and 40/40 rapid inflations after delivery. They intubated 20 esophagi, and found 6/20 (30%) false positives that refilled slowly (4-10 seconds). They surmise that the false negative results are likely due to a reduced FRC in the parturient patient, and the false positives were likely due to changes in pregnancy such as decreased LES tone and increased intragastric pressure. They conclude that this device is not reliable in near term pregnant patients. SCOTI vs. Wee. An assessment of two oesophageal intubation detection devices. Lockey DJ, Woodward W: Anaesthesia 1997;52:242-243. This paper compares the use of an EDD and a SCOTI device on 50 patients. The EDD correctly identified all 50 tracheal and all 50 esophageal tubes. The SCOTI correctly identified 48/50 tracheal and 50/50 esophageal tubes. The authors conclude "the SCOTI is no better than the simple, cheap and reliable Wee device."-------back to top PREHOSPITAL AND EMERGENT INTUBATION STUDIES The syringe aspiration technique to verify endotracheal tube position. Jenkins WA, Verdile VP, Paris PM: Am J Emerg Med 1994;12:413-416. This study was conducted in the emergency department and prehospital medical care setting. The authors used an EDD (calling it the syringe aspiration technique or SAT) on 90 consecutive patients requiring urgent intubation. 51 intubations occurred in the emergency department, 39 in the prehospital setting. Half of the patients were suffering cardiac arrest. Most intubations were performed by paramedics, residents or critical care staff, but all device use was performed following intubation by one of the authors (all MD's). Endotracheal tube location was then confirmed using a combination of clinical judgment, direct laryngoscopy, ETCO2 and CXR as deemed necessary. In 88 patients the EDD filled immediately and completely and ETT location was subsequently confirmed to be tracheal. One of these patients had a large hemopneumothorax and nine had pulmonary edema - these conditions did not affect EDD results in this study. In two patients there was resistance to aspiration. Esophageal location was confirmed by direct laryngoscopy. Both tubes were placed in the field in patients suffering cardiac arrest. Neither tube was recognized to be esophageal by the intubating personnel. The authors conclude that "The results of this study would suggest that the SAT is a safe, reliable, and effective device for determining ETT position in patients with ... conditions necessitating urgent airway control." "Its low cost, facility, and accuracy suggest that the SAT might be a useful tool for routine ED and out-of -hospital determination of ETT position." "There are many advantages to using the SAT. The concept is simple... Training with the device, therefore, should be minimal.... the technique is rapid ... In addition, the SAT, unlike the ETCO2 detector, appears to be reliable in both breathing and non breathing patients. Finally, the SAT is inexpensive." Comparison of an esophageal detector device to a colorimetric end-tidal CO2 detector in the pre-hospital setting. Schaller RJ, Huff JS, Zahn A: Abstract in S. Med Journal 1994;84:S30. This is a pre-hospital study which randomized patients to have either an EDD or a disposable ETCO2 device used to confirm ETT location. 43 patients were included - 25 using the EDD and 18 using the ETCO2 device. 84% of the patients were suffering cardiac arrest at the time of intubation. In the EDD group, two esophageal intubations occurred and were immediately detected. No esophageal intubations occurred in the ETCO2 group, however in two cases there was no color change and in two cases minimal change occurred despite tracheal intubation. 76% of the EMS providers who used both devices preferred the EDD. Syringe aspiration technique for confirmation of correct endotracheal intubation position in prehospital emergency care. Coleman R, O'Brien D, Lawson R: S Med Journal 1994;87:S32. Clinical judgment was compared to a 60 cc syringe type EDD in 78 prehospital intubations. All 78 were believed to be properly placed in the trachea based on initial clinical judgment. However, when the EDD failed to fill in two cases, re-examination demonstrated these two tubes to be esophageal and led to re-intubation. The authors conclude "that for pre-hospital emergency care, SAT appears to be a useful adjunct to standard techniques for confirming that intubations are intratracheal. Efficacy of the Self-inflating bulb for confirmation of emergency tracheal intubation in critically ill patients. Czinn EA, Wafai Y, Salem MR, et al: Abstract in Anesthesiology 1995;83(3A):A266. This study was designed to assess the effectiveness of the bulb (75cc) EDD in confirming emergency tracheal intubation in critically ill, hospitalized patients. 123 adults were intubated, 98 for respiratory failure, 25 for cardiac arrest. Difficulty of intubation was graded using Lahane grades I through IV. 24% of intubations were grade III or IV. Nine esophageal intubations occurred. 8 were accurately identified, one was misidentified. The missed patient had massive insufflation of his stomach immediately prior to bulb aspiration. 16 (13%) of tracheal tubes had either slow (4 to 10 seconds ) or absent (over 10 seconds) inflation and were considered false negatives. Most of these patients had copious secretions or reduced airway volumes: pulmonary secretions-7, pulmonary edema-2, endobronchial intubation-2, severe bronchospasm-1, severe atelectasis-1, pulmonary contusion-1, unknown-2. The authors conclude that false negatives are more frequent in critically ill patients with pulmonary disease. That this is due to partial obstruction of the tracheobronchial tree/reduced volumes for aspiration, and that like all other methods of verifying correct tube placement, bulb-EDD's have limitations. They recommend that the bulb is useful for identifying proper placement of endotracheal tubes, but it must be used in conjunction with other clinical signs and aids. Prehospital use of a prototype esophageal detection device: A word of caution. Marley CD, Eitel DR, Koch MF, et al: Prehosp Disaster Med 1996;11(3):223-227. 6 EMS systems entered a total of 92 patients (105 intubations) into this study using a 100cc bulb-EDD to determine its efficacy in the prehospital setting. 17 esophageal intubations occurred, all were detected. 88 tracheal intubations were assessed, 18 were slow (over 5 seconds) or non-inflators (78% specific). "Most of those" occurred in patients in whom the ETT was beyond the 22 cm at the lips or in patients who had fluid in their lungs. The authors conclude that many variables affect the identification of correct endotracheal tube placement, and that intubators must not rely too heavily on any one method for identifying tube location, but must use a combination of methods to assure proper placement. The esophageal detector device versus end tidal carbon dioxide level in emergency intubation. Bozeman W, Hexter D, Liang HK, Kelen GD: Ann Emerg Med 1996;27:595-599. These authors directly compared an EDD with ETCO2 in 100 emergently intubated patients. 99 tubes were tracheal, one was esophageal. The EDD detected the esophageal tube and 98/99 tracheal tubes (99%). There was an indeterminate answer in one tracheal tube in a patient suffering from pulmonary edema whose tube was occluded with secretions. ETCO2 was incorrect in 13 cases (13%, p<0.01). Two occurred in pulmonary edema, eleven in cardiac arrest. Of the 37 patients in cardiac arrest, ETCO2 failure rate was 30% while the EDD detected 100%. They concluded that "the EDD is a simple, inexpensive device that, unlike ETCO2, reliably confirms tracheal intubation in the ED population ..." Comparison of self inflating bulb and expired CO2 to confirm endotracheal placement after emergency intubation. Kasper CL, Deem S: Anesthesiology 1998;88(4):898-902. These authors compared colorimetric ETCO2 (Easi-Cap™), infrared ETCO2 (Stat-Cap™) and bulb aspiration type esophageal detector devices (Tube-Chek™) in 300 emergent intubations that occurred within their hospital. All intubations were performed by an anesthesiologist using strict guidelines. The bulb was not available for 3 attempts (1%), colorimetric ETCO2 for 2 (1%) and infrared CO2 for 32 cases (10% - primarily due to mechanical problems or battery failure). 19 intubations were esophageal and were detected by all devices. The 3 false negatives occurring with the bulb were in patients with COPD (1), copious secretions (1) and obesity (1). The 3 false negatives with ETCO2 occurred during CPR. The authors conclude that these devices are equal in their accuracy provided rigid protocols for their use are followed, They caution practitioners to be aware of possible false negative results in patients with secretions, obesity and COPD (bulb) or CPR (ETCO2). They go on to state that the cost of the bulb is considerably less than that of the colorimetric device, which along with its reliability and portability make it an attractive alternative for confirming ETT position in the emergency setting. Use of a standard 2-oz catheter-tip syringe to confirm endotracheal tube placement. Saavedra B, Sakles JC: Abstract in Acad Emerg Med 1997;4:519 (abstract 544). 100 patients intubated in the field or ED had this device used to confirm ETT location. Of 97 tracheal tubes, the device was inconclusive in one, but correctly identified the remaining 96 (99%), including 18 in whom ETCO2 failed (due to cardiac arrest). The 3 esophageal intubations were all correctly identified. Out-of-hospital experience with the syringe esophageal detector device. Pelucio M, Halligan L, Dhindsa H: Acad Emerg Med 1997;4:563-568. A convenience sample of patients intubated in the field, and in whom this device was used, and in whom the tube location was subsequently confirmed by an MD were entered. 168 of 374 intubations met criteria and were evaluated. 156 of 158 tracheal tubes were correctly identified (99%). The two missidentified cases were in patients with a large amount of fluid in the airway. 5 of 10 esophageal intubations were correctly identified. It is unclear from the data why this particular study had these poor esophageal detection rates, which are very different from all other studies. Using the syringe (SAT) in the out-of-hospital setting to minimize unrecognized esophageal intubations. Sternig KJ, Pirrallo RG, Szewczuga D, et al: NAEMSP 1997 mid year abstracts. A convenience sample of patients intubated in the field, and in whom this device was used were entered. The device was used 588 times on 460 patients (out of a total of 986 intubations in the field that year). Of the patients in whom a CXR could be located to use as a "gold standard" (132 total) all 132 had the tube in the trachea but 17% required repositioning. Of the raw data (all 460 patients-personal communication) there were 52 esophageal intubations which were all identified, and 23/588 (4%) where the device failed to fill, but clinical judgement indicated tracheal location. Of these 23, 15 of 23 were right mainstem intubations and 4 of 23 had pulmonary edema. Using this device and clinical judgment, no patient was found to have an unrecognized esophageal intubation on arrival in the emergency department.-----back to top An evaluation of the esophageal detector device using a cadaver model. Oberly D, Stein S, Hess D, Eitel D, Simmons M: Am J Emerg Med 1992;10(4):317-320. In this study 10 cadavers were intubated in both the trachea and the esophagus and an esophageal detector device was used on one of the tubes. 45 esophageal trials and 45 tracheal trials were conducted. The EDD identified 100% of tracheal tubes. For esophageal intubations, the EDD did not inflate in 44 cases and filled with vomitus in 1 case. It thus correctly identified all esophageal intubations. All evaluators felt the EDD was simple and easy to use. The authors concluded that the EDD was 100% accurate, even in patients who had expired. They went on to say "the esophageal detector device may be an ideal method for detection of esophageal intubation in cardiac arrested patients because it is inexpensive, it requires no calibration or warm up, it is rapid and simple, and it is not perfusion dependent." The esophageal detector device: A rapid and accurate method for assessing tracheal versus esophageal intubation in a porcine model. Foutch RG, Magelssen MD MacMillan JG: Ann Emerg Med 1992;21:1073-1076. This study used an animal model to compare the esophageal detector device, a disposable colorimetric end-tidal CO2 monitor and standard clinical methods for detection of proper endotracheal tube placement. The study was divided into two parts. In part one, the ETT was placed in either the esophagus or the trachea. Blinded volunteers were asked to assess location using one of the three methods. Those who used the EDD were correct 100% of the time, requiring an average of 13.2 seconds to do so. Those who used end-tidal CO2 monitors were also 100% accurate in this non-cardiac arrest protocol. They required 31.5 seconds to determine location. Clinical methods were accurate 70% of the time, and required an average of 39 seconds. In part two, an ETT was again placed in both the trachea and in the esophagus. The esophageal tube then had 20 breaths ventilated through it. This resulted in a tense, distended abdomen. The esophageal detector device was again blindly tested. Despite a distended, air filled stomach, the EDD was 100% accurate. The authors conclude the following: 1. "The esophageal detector device was superior to both end-tidal CO2 and clinical methods in the time required to determine endotracheal tube position." 2. "Data demonstrated 100% accuracy for both the esophageal detector device and the end-tidal CO2 monitor. There was a 30% error rate among the clinical methods group." 3. "The mechanics of the esophageal detector device may offer a distinct advantage over the end-tidal CO2 monitor. The esophageal detector device exploits anatomical structure to differentiate tracheal from esophageal intubation. The end-tidal CO2 monitor depends on less constant physiological parameters. The esophageal detector device offers a potential advantage to prehospital airway managers in that it easily can be used in darkened environments, whereas the end-tidal CO2 monitor requires sufficient light to read the color change." 4. "Bag ventilation of an endotracheal tube did not interfere with the accuracy of the esophageal detector device." "In-field" assessment of endotracheal tube placement. Maleck W, Petroianu G, Altmannsberger S, et al: Prehospital and disaster med 1995; 10(3):111/S19. 50 pigs were intubated in the trachea and the esophagus. Inexperienced personnel (students) were then allowed to determine the position of 25 tracheal tubes and 25 esophageal tubes using three devices: esophageal detector device, EasyCap™ or MiniCap™. All decisions were correct, however regurgitation occurred 6 times using the capnographic type devices prior to CO2 detection. No regurgitation was noted with the EDD. The authors "recommend initial control of ET-tube position with an ODD in any emergency intubation, because it is: (a) CO2-independent (works well in cardiac arrest); (b) quick; and (c) without risk of regurgitation." The esophageal detector device: Accuracy and reliability in difficult airway settings. Kapsner CE, Seaburg DC, Stengel C, et al: Prehosp Dis Med 1996;11:60-62. Five swine underwent a variety of intubations: Esophageal, esophageal with 1 liter of air instilled, tracheal, tracheal with 5ml/kg water instilled, and right mainstem intubation. An EDD syringe was used to determine tube location. The EDD properly located all tubes with the exception of one tracheal tube in the fluid filled lung model (it properly located 4 of 5 in this situation). The authors conclude "the EDD provides a simple and inexpensive technique for determining ET-tube placement in most clinical situations."----back to top Comments on the oesophageal detector device [letter, comment]. Wee MKY: Anaesthesia 1989;44:930-931 This is a letter describing doctor Wee's experience using the EDD in over 2000 patients. Of these cases, 27 were inadvertent esophageal intubations. He detected 100% of these immediately. He describes 25 instances of tracheal intubation which might be interpreted by the inexperienced user as equivocal due to slight "resistance" during aspiration. Most of these cases occurred in the obese. In all these cases, 20 to 40 cc of air could be aspirated, prior to any resistance. He stated "this resistance is quite different from the marked resistance encountered during aspiration of a tube in the oesophagus." He recommends against "enthusiastically" aspirating because this may lead to adherence of the ETT bevel to the tracheal mucosa. The oesophageal detector device in the asthmatic patient [letter, comment]. Baraka A: Anaesthesia 1993;48(3):275. This is a letter to the editor in which Dr. Baraka describes three instances in which the esophageal detector device gave equivocal if not misleading results. Using a balloon type device, he has experienced slow refilling in two patients and no refilling in one patient. Two of these patients had tracheal compression and one had severe asthma. He wishes to emphasize the fact that there are times when the esophageal detector device may give misleading results and one must use one's clinical judgment in patients with potential tracheal injury and/or severe bronchospasm. The esophageal detector device in the morbidly obese [letter]. Baraka A, Choueiry P, Salem R: Anesth-Analg. 1993;77(2):400. This is a letter to the editor describing experience using a balloon type esophageal detector device on a morbidly obese patient. The authors describe a case where the bulb inflated slowly rather than rapidly as expected. This occurred despite the fact that the trachea was properly intubated. They wish to make people aware that in patients with morbid obesity, severe bronchospasm, pulmonary edema or adult respiratory distress syndrome (ARDS) EDD results may be equivocal. Esophageal detector device: Not always reliable [letter]. Heidegger T, Heim C: Ann Emerg Med 1996;28(5):582. These authors studied the bulb EDD on 517 patients ages 3 to 89. They had 22 esophageal intubations that were all detected. They had an 11% false negative rate, of which 82% were in patients with obesity, COPD or upper airway infectious secretions. They recommend careful evaluation of non-inflators to determine tube location, and "when in doubt, take it out!" P/N 30-0105 Rev. 5/98 ------back to top
| |||||||||
 |
|
|
|
|
|
|
|
|
|
| Home | Richiesta Info |
