Transesophageal echocardiography instead or in addition to transthoracic echocardiography in evaluating haemodynamic problems in intubated critically ill patients

BACKGROUND: Transesophageal echocardiography (TEE) performed by intensivists is increasingly used in critically ill patients. However, TEE is usually not the preferred monitoring tool, especially when transthoracic echocardiography (TTE) appears to have addressed the clinical problems. As a result, it remains largely unknown whether TEE is a clinically valuable replacement or supplement for TTE as a primary tool in evaluating haemodynamic problems in critically ill surgical patients. The purpose of this study was to assess the diagnostic and therapeutic value of TEE instead or in addition to TTE in critically ill surgical patients with hemodynamic instability. METHODS: A prospective observational study was conducted. A total of 68 consecutive patients were enrolled from December 2016 to February 2018. TEE was routinely performed in addition to TTE, and the imaging data from TTE and TEE were successively disclosed to two different primary physicians, who reported any resulting changes in management. The two physicians were required to reach a consensus if there was any disagreement. The results of the additional TEE examination were compared with the clinical findings and TTE information. The image quality of TTE views was classified as a good (score 2), suboptimal (score 1) or poor view (score 0). According to the scores of TTE images, the patients were divided into two groups: patients with adequate TTE views (score ≥6) and inadequate TTE views (score <6). RESULTS: The results of additional TEE examination were classified into four categories. TEE failed to provide additional information about the initial diagnosis and therapy (class 1) in 26 patients (38.2%). Of the remaining 42 patients (61.8%), TEE instead or in addition to TTE revealed new findings or led to significant changes in therapy, as TTE supplied inadequate information. TEE used in addition to TTE led to a new diagnosis without therapeutic implications (class 2) in 11 patients (16.2%) and made a major clinical contribution leading to a therapeutic change (class 3) in 23 patients (33.8%). TEE used instead of TTE determined the diagnosis and therapy in 8 patients (11.8%) whose haemodynamic problems could not be addressed by TTE (class 4). In total, TEE had critical therapeutic benefits (class 3 and 4) that was not provided by TTE in 31 patients (45.6%). Of particular concern was that TEE had a higher proportion of therapeutic benefits to patients with inadequate TTE views than those with adequate TTE views (54.3% vs. 27.3%, P=0.036). CONCLUSIONS: TEE as a feasible clinical tool is useful for critically ill surgical patients with hemodynamic instability, especially for the patients with inadequate TTE views. TEE instead or in addition to TTE could provide valuable information for diagnosis, which may bring significant therapeutic benefits.