Rapid 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.

A 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.

During 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.

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

Disaster management is a complex and difficult undertaking that may involve limited health care resources and evaluation of multiple victims. The objectives of this study were to evaluate the feasibility of real-time ultrasound video transmission from a simulated disaster triage location via commercially available video mobile phones and assess the ability of emergency physicians to accurately interpret the transmitted video of Focused Assessment with Sonography for Trauma (FAST) ultrasound examinations.

This was a prospective, observational study that took place at a simulated disaster scene put on for an Advanced Disaster Life Support (ADLS) course. The second component occurred at a Level I academic urban emergency department (ED) with an annual census of 78,000. Nineteen subjects at a simulated disaster scene were scanned using a SonoSite Titan ultrasound system (Bothell, Washington USA). An off-the-shelf, basic, video-capable mobile phone was used to record each ultrasound examination; and then immediately transmit the videos to another mobile phone approximately 170 miles away. The transmitted video was received by three emergency physicians with hospital credentialing in emergency ultrasound. Each FAST examination video was assessed for pathology, such as free fluid. The reviewers graded the image quality and documented the overall confidence level regarding whether or not a complete and adequate examination was visualized. Spearman's rank correlation coefficient was used to examine the agreement between the reviewers and the sonologist who performed the ultrasound examinations.

A total of 19 videos were transmitted. The median time for transmission of a video was 82.5 seconds (95% CI, 67.7 seconds-97.3 seconds). No video failed to transmit correctly on the first attempt. The image quality ratings for the three reviewers were 7.7, 7.5, and 7.4 on a 10-point Likert scale. There was a moderate agreement between the reviewers and sonologist in image quality rating and overall confidence level scores (rho = 0.6).

Real-time portable ultrasound video transmission via commercially available video mobile phones from a simulated disaster triage location is feasible and emergency physicians were able to accurately interpret video of FAST ultrasound examinations.

AdhikariS , BlaivasM , LyonM , ShiverS . Transfer of Real-time Ultrasound Video of FAST Examinations from a Simulated Disaster Scene Via a Mobile Phone. Prehosp Disaster Med. 2014;29(3):1-4.

Exsanguination from a femoral artery wound can occur in sec-onds and may be encountered more often due to increased use of body armor. Some military physicians teach compression of the distal abdominal aorta (Abdominal Aorta) with a knee or a fist as a temporizing measure.

The objective of this study was to evaluate if complete collapse of the Abdominal Aorta was feasible and with what weight it occurs.

This was a prospective, interventional study at a Level-I, academ-ic, urban, emergency department with an annual census of 80,000 patients. Written, informed consent was obtained from nine male volunteers after Institutional Research Board approval. Any patient who presented with abdominal pain or had undergone previous abdominal surgery was excluded from the study. Subjects were placed supine on the floor to simulate an injured soldier. Various dumbbells of increasing weight were placed over the distal Abdominal Aorta, and pulsed-wave Doppler measurements were taken at the right common femoral artery (CFA). Dumbbells were placed on top of a tightly bundled towel roughly the surface area of an adult knee. Flow measurements at the CFA were taken at increments of 20 pounds. This was repeated with weight over the proximal right artery iliac and distal right iliac artery to eval- uate alternate sites. Descriptive statistics were utilized to evaluate the data.

The mean velocity through the CFA was 75.8 cm/ sec at 0 pounds. Compression of the Abdominal Aorta ranging 80 to 140 pounds resulted in no flow in the CFA. A steady decrease in mean flow velocity was seen starting with 20 pounds. Flow velocity decreased more rapidly with compression of the prox- imal right iliac artery, and stopped in all nine volunteers by 120 pounds of pressure. For all nine volunteers, up to 80 pounds of pressure over the distal iliac artery failed to decrease CFA flow velocity, and no subject was able to tolerate more weight at that location.

Flow to the CFA can be stopped completely with pressure over the distal Abdominal Aorta or proximal iliac artery in catastrophic wounds. Compression over the proximal iliac artery worked best, but a first responder still may need to apply upward of 120 pounds of pressure to stop exsanguination.