Esophageal intubation with indirect clinical tests during emergency tracheal intubation: a report on patient morbidity

The ultrasound is a noninvasive diagnostic method and gained increasing importance in the plane of the emergency. Their usefulness for the recognition of anatomical structures and detection of a difficult airway. This method increases the quality of care in the emergency room. The objective of the study was to evaluate the ultrasound ́ training for the identification of normal and variation in the anatomic airway, and their usefulness during tracheal intubation. There were two periods of training. First period: 2013- February/2013 July, learning of normal human anatomy in cadaveric material corpses (in formaldehyde 10%) and the identification of normal anatomic structures. Training in the use of ultrasound (transdutor 7.5 MHz). Second period: August/2013- December/2013, case of patients that requiring emergency intubation were analyzed in which airway ultrasound were performed. The anatomo-clinical-surgical/ultrasonographic correlation was analyzed during placement of the endotracheal tube and its identification in the airway. Two hundred twenty ultrasound examinations were performed during tracheal intubation. 134 (60.91%) were made during surgery, 110 (82.09%) were programmed surgery and 24 (17.91%) emergency surgery; and 86 (39.09%) required intubation in shock room. Two groups were classified: Group 1: surgically treated patients (Group A: programed surgery: 104 (94.54%) correctly identified intubation, and in 6 (5.46%) esophageal intubation was detected, and Group B emergency surgery: in 23 (95.83%) correct placement was identified and 1 (4.17%) was esophageal intubation. Group 2: patients intubated in the shock room: 80 (93.03%) were correctly intubated and, 6 (6.97%) had esophageal intubation. In all groups, esophageal intubation was detected only in 13 patients (5.91%), using ultrasound during the procedure. The use of ultrasound for the recognition of the airway, is useful to favor the correct intubation and management of difficult airway. The ultrasound training and anatomo-clinical-surgical application is critical because it would improve the quality of care and decreasing the risk of adverse events.

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Efficacy of the Self-inflating Bulb in Confirming Tracheal Intubation in the Morbidly Obese

Anesthesiology ◽

10.1097/00000542-199608000-00004 ◽

1996 ◽

Vol 85 (2) ◽

pp. 246-253 ◽

Cited By ~ 37

Author(s):

David J. Lang ◽

Yaser Wafai ◽

Ramez M. Salem ◽

Edward A. Czinn ◽

Ayman A. Halim ◽

...

Keyword(s):

Tracheal Intubation ◽

False Negative ◽

The Self ◽

Morbidly Obese ◽

Esophageal Intubation ◽

Obese Patients ◽

True Positive ◽

Negative Results ◽

False Negative Results ◽

Positive Results

Background This study was designed to determine the incidence of false-negative and false-positive results when the self-inflating bulb (SIB) is used to differentiate tracheal from esophageal intubation in morbidly obese patients using two techniques. In technique 1, the SIB is compressed before it is connected to the tube; in technique 2, the SIB is compressed after connection to the tube. Methods With institutional review board approval, 54 consenting adult morbidly obese patients (body mass index > 35) undergoing elective surgical procedures were included in the study. After anesthetic induction and muscle relaxation, both the trachea and esophagus were intubated under direct vision with identical cuffed tubes. The efficacy of the SIB in verifying the position of both tubes was tested by a second anesthesiologist. The speed of reinflation was graded as rapid ( < 4 s) or none ( > 4 s), using both techniques. In the case of tracheal intubation, the absence of reinflation was recorded as a false-negative, whereas in cases of esophageal intubation, rapid reinflation was recorded as a false-positive. Identification of tube location by the second anesthesiologist was based on SIB reinflation results from techniques 1 and 2, as well as the presence of a flatuslike sound elicited by technique 2 in esophageally placed tubes. All patients were retested by the SIB after receiving three breaths of 400-500 ml each. In all patients exhibiting false-negative results, six obese patients exhibiting true-positive results, and four nonobese patients exhibiting true-positive results, tracheal responses to the SIB maneuvers were observed directly by a flexible fiberoptic bronchoscope incorporating an airtight system, 15-20 min after mechanical ventilation was instituted. Results The incidence of false-negative results was initially 30% with technique 1 and 11% with technique 2, but decreased to 4% when technique 2 was used after the delivery of three breaths. The second anesthesiologist initially identified tube location in 92.5% of patients correctly. After the delivery of three breaths, tube location was correctly identified in 96.3% of patients. Fiberoptic bronchoscopic examination of the patients exhibiting false-negative results revealed exaggerated inward bulging of the posterior tracheal membrane during reinflation of the SIB when technique 1 was used. Conclusions Contrary to previous investigations in healthy patients, the current study demonstrates a high incidence of false-negative results when the SIB is used to confirm tracheal intubation in morbidly obese patients. If the SIB is used, the technique should include compression of the SIB after connection to the tube and should be used in conjunction with other clinical signs and technical aids. The mechanism of false-negative results in these patients seems to be related to reduction of caliber of airways secondary to a marked decrease in functional residual capacity, and collapse of large airways due to invagination of the posterior tracheal wall when sub-atmospheric pressure is generated by the SIB.

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Validation Study of Two-microphone Acoustic Reflectometry for Determination of Breathing Tube Placement in 200 Adult Patients

Anesthesiology ◽

10.1097/00000542-200212000-00007 ◽

2002 ◽

Vol 97 (6) ◽

pp. 1371-1377 ◽

Cited By ~ 23

Author(s):

David T. Raphael ◽

Maxim Benbassat ◽

Dimiter Arnaudov ◽

Alex Bohorquez ◽

Bita Nasseri

Keyword(s):

Tracheal Intubation ◽

False Negative ◽

Adult Patients ◽

Tube Placement ◽

Segment Length ◽

Esophageal Intubation ◽

Cross Sectional ◽

Identification Rate ◽

Breathing Tube

Background Acoustic reflectometry allows the construction of a one-dimensional image of a cavity, such as the airway or the esophagus. The reflectometric area-distance profile consists of a constant cross-sectional area segment (length of endotracheal tube), followed either by a rapid increase in the area beyond the carina (tracheal intubation) or by an immediate decrease in the area (esophageal intubation). Methods Two hundred adult patients were induced and intubated, without restrictions on anesthetic agents or airway adjunct devices. A two-microphone acoustic reflectometer was used to determine whether the breathing tube was placed in the trachea or esophagus. A blinded reflectometer operator, seated a distance away from the patient, interpreted the acoustic area-distance profile alone to decide where the tube was placed. Capnography was used as the gold standard. Results Of 200 tracheal intubations confirmed by capnography, the reflectometer operator correctly identified 198 (99% correct tracheal intubation identification rate). In two patients there were false-negative results, patients with a tracheal intubation were interpreted as having an esophageal intubation. A total of 14 esophageal intubations resulted, all correctly identified by reflectometry, for a 100% esophageal intubation identification rate. Conclusions Acoustic reflectometry is a rapid, noninvasive method by which to determine whether breathing tube placement is correct (tracheal) or incorrect (esophageal). Reflectometry determination of tube placement may be useful in airway emergencies, particularly in cases where visualization of the glottic area is not possible and capnography may fail, as in patients with cardiac arrest.

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Avoid the Goose! Paramedic Identification of Esophageal Intubation by Ultrasound

Prehospital and Disaster Medicine ◽

10.1017/s1049023x18000651 ◽

2018 ◽

Vol 33 (4) ◽

pp. 406-410 ◽

Cited By ~ 3

Author(s):

Penelope C. Lema ◽

Michael O’Brien ◽

Juliana Wilson ◽

Erika St. James ◽

Heather Lindstrom ◽

...

Keyword(s):

Prospective Observational Study ◽

Point Of Care ◽

Rapid Identification ◽

Descriptive Statistics ◽

Point Of Care Ultrasound ◽

Esophageal Intubation ◽

Publication Type ◽

Employment History ◽

Patient Morbidity ◽

Study Session

AbstractObjectivesRapid identification of esophageal intubations is critical to avoid patient morbidity and mortality. Continuous waveform capnography remains the gold standard for endotracheal tube (ETT) confirmation, but it has limitations. Point-of-care ultrasound (POCUS) may be a useful alternative for confirming ETT placement. The objective of this study was to determine the accuracy of paramedic-performed POCUS identification of esophageal intubations with and without ETT manipulation.MethodsA prospective, observational study using a cadaver model was conducted. Local paramedics were recruited as subjects and each completed a survey of their demographics, employment history, intubation experience, and prior POCUS training. Subjects participated in a didactic session in which they learned POCUS identification of ETT location. During each study session, investigators randomly placed an ETT in either the trachea or esophagus of four cadavers, confirmed with direct laryngoscopy. Subjects then attempted to determine position using POCUS both without and with manipulation of the ETT. Manipulation of the tube was performed by twisting the tube. Descriptive statistics and logistic regression were used to assess the results and the effects of previous paramedic experience.ResultsDuring 12 study sessions, from March 2014 through December 2015, 57 subjects participated, evaluating a total of 228 intubations: 113 tracheal and 115 esophageal. Subjects were 84.0% male, mean age of 39 years (range: 22 - 62 years), with median experience of seven years (range: 0.6 - 39 years). Paramedics correctly identified ETT location in 158 (69.3%) cases without and 194 (85.1%) with ETT manipulation. The sensitivity and specificity of identifying esophageal location without ETT manipulation increased from 52.2% (95% confidence interval [CI], 43.0-61.0) and 86.7% (95% CI, 81.0-93.0) to 87.0% (95% CI, 81.0-93.0) and 83.2% (95% CI, 0.76-0.90) after manipulation (P<.0001), without affecting specificity (P=.45). Subjects correctly identified 41 previously incorrectly identified esophageal intubations. Paramedic experience, previous intubations, and POCUS experience did not correlate with ability to identify tube location.Conclusion:Paramedics can accurately identify esophageal intubations with POCUS, and manipulation improves identification. Further studies of paramedic use of dynamic POCUS to identify inadvertent esophageal intubations are needed.LemaPC, O’BrienM, WilsonJ, St. JamesE, LindstromH, DeAngelisJ, CaldwellJ, MayP, ClemencyB.Avoid the goose! Paramedic identification of esophageal intubation by ultrasound. Prehosp Disaster Med.2018;33(4):406–410

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Difficult tracheal intubation secondary to a tracheal diverticulum and a 90 degree deviation in the trachea

Anaesthesia ◽

10.1046/j.1365-2044.2000.01664-18.x ◽

2000 ◽

Vol 55 (9) ◽

pp. 923-925 ◽

Cited By ~ 16

Author(s):

R. Davies

Keyword(s):

Tracheal Intubation ◽

Difficult Tracheal Intubation ◽

Tracheal Diverticulum ◽

Degree Deviation

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Test Validation Without Measurement

European Journal of Psychological Assessment ◽

10.1027/1015-5759/a000253 ◽

2016 ◽

Vol 32 (3) ◽

pp. 204-214 ◽

Cited By ~ 2

Author(s):

Emilie Lacot ◽

Mohammad H. Afzali ◽

Stéphane Vautier

Keyword(s):

Test Data ◽

Test Scores ◽

Scientific Explanation ◽

Test Validation ◽

Clinical Tests ◽

Ethical Perspective ◽

Power Of Test ◽

Memory Accuracy ◽

Social Uses ◽

Special Case

Abstract. Test validation based on usual statistical analyses is paradoxical, as, from a falsificationist perspective, they do not test that test data are ordinal measurements, and, from the ethical perspective, they do not justify the use of test scores. This paper (i) proposes some basic definitions, where measurement is a special case of scientific explanation; starting from the examples of memory accuracy and suicidality as scored by two widely used clinical tests/questionnaires. Moreover, it shows (ii) how to elicit the logic of the observable test events underlying the test scores, and (iii) how the measurability of the target theoretical quantities – memory accuracy and suicidality – can and should be tested at the respondent scale as opposed to the scale of aggregates of respondents. (iv) Criterion-related validity is revisited to stress that invoking the explanative power of test data should draw attention on counterexamples instead of statistical summarization. (v) Finally, it is argued that the justification of the use of test scores in specific settings should be part of the test validation task, because, as tests specialists, psychologists are responsible for proposing their tests for social uses.

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