Failed tracheal intubation which is not detected in time is a dangerous state. Capnography being the most frequently used tool to assess tracheal intubation does not always allow diagnosing this state in a prompt manner, for instance when the effective cardiac activity stopped. The objective of the study : to define specific features of ultrasound verification of the position of endotracheal tube (ETT). Methods . 20 patients undergoing surgery in a maxillofacial surgery ward were examined. All patients had ultrasound scanning of trachea before, during and after endotracheal intubation. Ultrasound examinations were done with four positions of the ultrasound sensor: longitudinal (supra-tracheal along the middle line), suprasternal, transcricoid and transthoracic positions. Results . The direct method in the longitudinal position allowed visualizing ETT in 100% of patient (n = 20), while in the other positions of the sensor (but for transthoracic one) it was possible to distinguish ETT only in 80% of cases (n = 16). The indirect methods (esophageal intubation, transthoracic position) detected the position of ETT in 100% of patients (n = 20). Conclusions . Ultrasound can be used to confirm the position of ETT during intubation providing high accuracy and reliability. It is possible but difficult to visualize endotracheal tube in trachea since it can be easily confused with the interface of tissue and air or some other anatomical formations. The use of reinforced tubes or filling the cuff with fluid greatly facilitates the finding of the endotracheal tube in trachea with ultrasound, especially in the longitudinal position of the sensor. The ultrasound is the fastest method of detecting esophageal intubation by finding the phenomenon of the double way. The transthoracic position is one of the additional methods to confirm that ETT is in trachea by identifying the phenomenon of pulmonary pleurae sliding.
Read full abstract