The esophageal detector device: accuracy and reliability in difficult airway settings.

INTRODUCTION: The esophageal detector device (EDD) recently has been found to assess endotracheal (ET) tube placement accurately. This study describes the reliability of the EDD in determining the position of the ET tube in clinical airway situations that are difficult. METHODS: This was a prospective, randomized, single-blinded, controlled laboratory investigation. Two airway managers (an emergency-medicine attending physician and a resident) determined ET-tube placement using the EDD in five swine in respiratory arrest. The ET tube was place in the following clinical airway situations: 1) esophagus; 2) esophagus with 1 liter of air instilled; 3) trachea; 4) trachea with 5 ml/kg water instilled; and 5) right mainstem bronchus. Anatomic location of the tube was verified by thoracotomy of the left side of the chest. RESULTS: There was 100% correlation between the resident and attending physician's use of the EDD. The EDD was 100% accurate in the determining tube placement in the esophagus, in the esophagus with 1 liter of air instilled, in the trachea, and in the right mainstem bronchus. The airway managers were only 80% accurate in detecting tracheal intubations when fluid was present. CONCLUSIONS: The EDD is an accurate and reliable device for detecting ET-tube placement in most clinical situations. Tube placement in fluid-filled trachea, lungs, or both, which occurs in pulmonary edema and drowning, may not be detected using this device.

Right lung ventilation in a porcine open-chest shock model.

OBJECTIVE: To determine the effect of selective right lung ventilation on gas exchange and hemodynamics when compared with bilateral lung ventilation in a porcine open-chest shock model. METHODS: A randomized, controlled laboratory investigation was performed using a static hemorrhagic shock model in 12 adult swine undergoing thoracotomy. The animals were subjected to a fixed 40% circulating blood volume hemorrhage over 20 minutes. Each animal was then assigned to either a tracheal (control) or a right mainstem (experimental) intubation group. Minute ventilation was held constant in both groups and tidal volumes were decreased by 33% in the right mainstem intubation group. Following intubation and left lateral thoracotomy, another 20% fixed-volume hemorrhage was instituted simultaneously with IV crystalloid and whole blood resuscitation for both groups over 30 minutes. Heart rate, blood pressure, and arterial blood gases were measured at 5-minute intervals. RESULTS: There was no significant difference between the control and experimental groups for any of the measured variables, including mean arterial pressure, pH, partial arterial pressure of CO2 (PaCO2), and PaO2, over time. All animals survived the study protocol. CONCLUSION: Selective right lung ventilation has no detrimental effect on gas exchange or hemodynamics when compared with standard bilateral lung ventilation in a porcine open-chest shock model.