Capnography alone is imperfect for endotracheal tube placement confirmation during emergency intubation.

This analysis primarily sought to determine the effectiveness of end-tidal capnography for tube placement confirmation during emergency airway management. Secondary objectives were validation of the rate of unanticipated esophageal placement during emergency intubation and quantification of the portion of intubations performed in patients with cardiac arrest where capnography is not recommended. The study was performed in two phases. For the primary objective, a meta-analysis was performed on all experimental capnography trials enrolling emergency populations. For the secondary objectives, inadvertent esophageal intubation and cardiac arrest rates were calculated from a large prospective multicenter observational study of emergency intubation cases. Data analysis included calculation of descriptive statistics, sensitivity, specificity, and confidence intervals (CI). Based on 2,192 intubations, a meta-analysis of previous capnography trials resulted in an aggregate sensitivity of 93% (95% CI 92-94%) and an aggregate specificity of 97% (CI 93-99%) for emergency tube placement confirmation. Thus, for emergency capnography use, the false-negative failure rate (tube in trachea but capnography reports esophagus) was 7% and the false-positive rate (tube in esophagus but capnography reports trachea) was 3%. This translates to potential harm for one patient in every 10 treated with capnographic confirmation alone (number needed to harm: 14 for false-negative, 33 for false-positive, and 10 for both). A further literature review demonstrated no sole method of tube placement confirmation is completely foolproof. Of 4,602 consecutive intubations reported to the National Emergency Airway Registry, 4% of emergency intubation attempts resulted in accidental esophageal intubation, and 10% occurred in nontraumatic cardiac arrest patients. During tracheal intubation of critically ill patients, it is concluded that the rate of accidental esophageal tube placement warrants continued improvement in emergency airway techniques. Misidentification of esophageal placement in the emergency setting may occur with capnography. Multiple methods of tube placement confirmation are superior to any single method because no single method has perfect accuracy.

[1]  R. Walls.  Rapid-sequence intubation comes of age. , 1996, Annals of emergency medicine.

[2]  B. Markovitz,et al.  Unusual cause of an absent capnogram. , 1989, Anesthesiology.

[3]  A. Baraka,et al.  Efficacy of the Self‐inflating Bulb in Confirming Tracheal Intubation in the Morbidly Obese , 1996, Anesthesiology.

[4]  G. Kelen,et al.  Esophageal detector device versus detection of end-tidal carbon dioxide level in emergency intubation. , 1996, Annals of emergency medicine.

[5]  M. Paloheimo,et al.  Capnography for Detection of Accidental Oesophageal Intubation , 1983, Acta anaesthesiologica Scandinavica.

[6]  R. Zalenski,et al.  Safety evaluation and confidence intervals when the number of observed events is small or zero. , 1997, Annals of emergency medicine.

[7]  G. M. Smith,et al.  Radiographic detection of esophageal malpositioning of endotracheal tubes. , 1990, AJR. American journal of roentgenology.

[8]  R. Ward,et al.  Esophageal Intubation: A Review of Detection Techniques , 1986, Anesthesia and analgesia.

[9]  M. Heller,et al.  End-tidal CO2 detection. , 1989, Annals of emergency medicine.

[10]  M. Heller,et al.  Verification of endotracheal tube placement with colorimetric end-tidal CO2 detection. , 1991, Annals of emergency medicine.

[11]  A. Thompson,et al.  Evaluation of an end-tidal CO2 detector during pediatric cardiopulmonary resuscitation. , 1995, Pediatrics.

[12]  I. Olkin,et al.  Improving the quality of reports of meta-analyses of randomised controlled trials: the QUOROM statement , 1999, The Lancet.

[13]  Comparison of end-tidal carbon dioxide, oxygen saturation and clinical signs for the detection of oesophageal intubation , 1989 .

[14]  J. E. Brian,et al.  Tonic-clonic activity after sufentanil. , 1987, Anesthesia and analgesia.

[15]  D. Raemer,et al.  Tracheal intubation is not invariably confirmed by capnography. , 1990, Anesthesiology.

[16]  J. Huff,et al.  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 , 1997, Prehospital and Disaster Medicine.

[17]  S. Deem,et al.  The Self‐inflating Bulb to Detect Esophageal Intubation during Emergency Airway Management , 1998, Anesthesiology.

[18]  M. Mehta,et al.  Reliability of Capnography in Identifying Esophageal Intubation With Carbonated Beverage or Antacid in the Stomach , 1991, Anesthesia and analgesia.

[19]  J. Stirt.  Endotracheal Tube Misplacement , 1982, Anaesthesia and intensive care.

[20]  A. Saville,et al.  Validity of a disposable end-tidal CO2 detector in verifying endotracheal tube placement in infants and children. , 1992, Annals of emergency medicine.

[21]  G. Schüpfer,et al.  Detection of oesophageal intubation: the cola complication , 1989, Anaesthesia.

[22]  K L Posner,et al.  Adverse respiratory events in anesthesia: a closed claims analysis. , 1990, Anesthesiology.

[23]  M. Banner,et al.  Portable devices used to detect endotracheal intubation during emergency situations: a review. , 1998, Critical care medicine.

[24]  H. Dhindsa,et al.  Out-of-hospital experience with the syringe esophageal detector device. , 1997, Academic emergency medicine : official journal of the Society for Academic Emergency Medicine.

[25]  J. Li,et al.  Complications of emergency intubation with and without paralysis. , 1999, The American journal of emergency medicine.

[26]  A. Baraka,et al.  The Self-inflating Bulb for Confirmation of Tracheal Intubation: Incidence and Demography of False Negatives , 1994 .

[27]  J. Robinson.  Respiratory recording from the oesophagus. , 1974, British medical journal.

[28]  T. Heidegger,et al.  Esophageal detector device: not always reliable. , 1996, Annals of emergency medicine.

[29]  M. Matthay,et al.  Death and Other Complications of Emergency Airway Management in Critically Ill Adults: A Prospective Investigation of 297 Tracheal Intubations , 1995, Anesthesiology.

[30]  J. Gillespie,et al.  Efficacy of Endotracheal Tube Cuff Palpation and Humidity in Distinguishing Endotracheal from Esophageal Intubation , 1988 .

[31]  M. Sayre,et al.  Confirmation of airway placement. , 1999, Prehospital emergency care : official journal of the National Association of EMS Physicians and the National Association of State EMS Directors.

[32]  J. Ornato,et al.  Multicenter study of a portable, hand-size, colorimetric end-tidal carbon dioxide detection device. , 1992, Annals of emergency medicine.

[33]  F. Cheney,et al.  A disposable end-tidal CO2 detector to verify endotracheal intubation. , 1991, Annals of emergency medicine.

[34]  Edward A. Walton,et al.  Death and other complications of emergency airway management in critically ill adults , 1995 .

[35]  B. Pollard,et al.  Accidental Intubation of the Oesophagus , 1980 .

[36]  T. Howells,et al.  Signs of endotracheal intubation , 1980, Anaesthesia.

[37]  L. Goodman,et al.  Alteration of endotracheal tube position. Flexion and extension of the neck. , 1976 .

[38]  H. Thode,et al.  Colorimetric end-tidal CO2 detector for verification of endotracheal tube placement in out-of-hospital cardiac arrest. , 1995, Academic emergency medicine : official journal of the Society for Academic Emergency Medicine.

[39]  A. Hald,et al.  Assessing the position of the tracheal tube The reliability of different methods , 1989, Anaesthesia.