Comparison of a Colorimetric End-Tidal CO₂ Detector and an Esophageal Aspiration Device for Verifying Endotracheal Tube Placement in the Prehospital Setting: A Six-Month Experience

Abstract

Introduction:Hand held, colorimetric, end-tidal CO2 detector devices are being used to verify correct endotracheal tube (ETT) placement. The accuracy of these devices has been questioned in situations of cardiac arrest. The use of the esophageal detector device (EDD) is an easy alternative for detection of ETT placement, and may be more accurate in situations of cardiac arrest.Hypothesis:The use of the esophageal aspiration device in comparison with a colorimetric end-tidal CO2 detector is more accurate in detecting proper ETT placement and easier to use in the prehospital setting than is the colorimetric end-tidal CO2 detection device.Methods:This was a prospective alternating weeks, 6-month study in a prehospital setting. Participants included all patients older than 18 years who were intubated by the Portsmouth, Virginia Emergency Medical Services (EMS) personnel from 01 July 1993 through 31 December 1993. The aspiration device used, also known as an esophageal detector device (EDD), was a 60 ml, luer-lock syringe attached to a 15 mm ETT adapter. Its efficacy was compared with an already accepted method of ETT position detection, the colorimetric endtidal CO2 detector. Each device was used on alternating weeks, and correct ETT placement was determined by the receiving emergency department physician using standard techniques. Chi-square analysis and Fisher's Exact test were used to compare parameters, time of device use, and ease of use. Sensitivity and specificity were calculated, and provider preference was assessed using a survey instrument administered following completion of the study.Results:There were 49 patients who met the inclusion criteria, but six were excluded because of situational circumstances rendering use of the device a possible compromise of patient care. Twenty-five patients were in the EDD group, and 18 were in the endtidal CO2 detector group. There was no statistically significant difference detected between groups for the gender ratio, underlying condition, CPR in progress, perceived difficulty of intubation, or percentage of nasotracheal intubation. The EDD was significantly easier to use (p<0.005). There was no statistically significant difference in time required for use of end-tidal CO2 detector device versus the EDD. The sensitivity and specificity for correct tracheal placement using the EDD was 100%, and the sensitivity for correct tracheal placement using the end-tidal CO2 detector device was 78%. Use of the EDD was preferred over use of the end-tidal CO2 detector device by 75% of participating EMS providers. One case of nasotracheal intubation with an ETT placement above the cords raised the question of accuracy of this device in situations where direct visualization is not utilized.Conclusion:The EDD was accurate in all cases of orotracheal intubation, and was easier to use than was end-tidal CO2 detector device. It was preferred by 75% of participating EMS providers. In cases in which the ETT may be above the vocal cords, caution must be used with interpreting the results obtained by use of the EDD.

Part 8: Advanced Life Support

“…Studies of colorimetric end-tidal CO 2 (ETCO 2 ) detectors (LOE D2 135,136 ; LOE D4 [137][138][139] ; LOE D5 140,141 ), the syringe aspiration esophageal detector device (LOE D1 133 ; LOE D4 142 ), the self-inflating bulb esophageal detector device (LOE D1), [132][133][134] and nonwaveform end-tidal CO 2 capnometers (LOE D2 130,143 ; LOE D4 137 ; LOE D5 141 ) showed that the accuracy of these devices is similar to the accuracy of clinical assessment (not uniformly defined across all studies) for confirming the tracheal position of a tracheal tube in victims of cardiac arrest.…”

Impact of the Final Rule on the Rate of Clinical Cardiac Arrest Research in the United States

“…The median number of patients enrolled across all 66 studies was 118 (IQR: 51-262; range: 10-3,327). 16 EU 1987 1986 Yes Hedges et al 17 US 1987 Yes Turner et al 18 US 1988 1985 Yes Barthell et al 19 US 1988 1986 No Forsman et al 20 EU 1989 1985 Yes Krischer et al 21 US 1989 1982 Yes Olson et al 22 US 1989 1986 No Ward et al 23 US 1989 * No Roine et al 24 EU 1990 1986 No Weaver et al 25 US 1990 1983 Yes Linder et al 26 EU 1991 * Yes No authors listed 27 US/EU 1991 * Yes Bartlett et al 28 US 1992 * No Brown et al 29 US 1992 1989 Yes Callaham et al 30 US 1992 1990 Yes Cohen et al 31 US 1992 1991 Yes Sack et al 32 US 1992 * No Cohen et al 33 US 1993 1992 No Halperin et al 34 US 1993 1988 Yes Longstreth et al 35 US 1993 1989 Yes Weaver et al 36 US 1993 1989 Yes Lurie et al 37 US 1994 1992 No Staudinger et al 38 US 1994 1988 Yes Choux et al 39 EU 1995 1991 No Dybvik et al 40 EU 1995 1987 Yes Orliaguet et al 41 EU 1995 * No Schwab et al 42 US 1995 1992 No Ellinger et al 43 EU 1994 1993 No Linder et al 44 EU 1997 1994 Yes Plaisance et al 45 EU 1997 1993 No Hilty et al 46 US 1997 * Yes Mader and Gibson 47 US 1997 1994 Yes Schaller et al 48 US 1997 1993 Yes Sherman et al 49 US 1997 * No Thel et al 50 US 1997 1993 Yes Gueugniaud et al 51 EU Of the 66 total studies, 43 (67%) began data collection and 29 (44%) were published prior to or during 1993. Of the 66 studies, 41 (62%) reported IRB approval.…”

Distinguishing esophageal from endotracheal intubation by measuring endotracheal tube cuff pressure

“…However, in emergency situations outside of the operating room environment, such as in pre-hospital or third world environments, these tools may not be available. The selfinflating bulb and colorimetric carbon dioxide detector are inexpensive devices that aid in detecting inadvertent esophageal intubation, though each have limitations [10,19]. Of note, patients in cardiac arrest may not generate adequate end-tidal carbon dioxide.…”