Utilization of echocardiography in Intensive Care Units: results of an online survey in Germany

Do I really need this transthoracic ECHO? An over-utilized test in trauma and surgical intensive care units

INTRODUCTION

Clinical use of transthoracic echocardiogram (TTE) in intensive care units (ICU) has dramatically increased without clear guidance on validated assessment indications, appropriateness, and patient value.

METHODS

A retrospective analysis of consecutive TTEs performed among patients admitted to a tertiary trauma/surgical ICU over 2.5 years was performed. A bivariate analysis and Poisson regression was used to compare patients who received a TTE. Sensitivity analysis was performed to assess patient factors that predict change in management based on TTE. An abnormal exam was defined as having at least one of the following: ejection fraction < 55%, wall motion, pericardial effusion, pericardial effusion, or other significant abnormality including filling defect. The effect on management was derived from clinical course. We hypothesize that these studies are usually normal and rarely lead to changes in clinical management.

RESULTS

912 TTEs were performed in 806 patients. The median age was 68 years (IQR 57, 77) and 63.5% were male. Syncope (21.7%) or hypotension/hypovolemia (20.5%) were the most common indications for a TTE. In total, 39.4% TTEs were abnormal and only 7.6% resulted in a change in management. Predictive factors associated with an abnormal exam included: age >50, serum troponin ≥0.1 ng/ml, abnormal ECG, and clinical suspicion of heart failure or acute myocardial infarction. A troponin cutoff level <0.25 ng/mL was the most reliable factor to predict no change in management after TTE with a negative predictive value of 94.3% (95% CI 93.1, 95.3).

CONCLUSION

TTE is commonly used for patient assessment in critically ill surgical patients but the majority of exams are normal without change in clinical management. Certain patient factors, such as troponin level, may help distinguish which patients would benefit from this diagnostic test. Given the considerable cost associated with TTE and the minimal effect on management, guidelines on appropriate use would provide improved patient value.

Subcostal TAPSE measured by anatomical M-mode: prospective reliability clinical study in critically ill patients

BACKGROUND

Tricuspid annular plane systolic excursion (TAPSE), evaluated from a four-chamber apical view, is an echocardiographic parameter for the detection of right ventricular systolic dysfunction (RVD). We decided to assess the reliability of TAPSE measured from subcostal view (sTAPSE) by anatomical M-mode imaging (AMM) for evaluation of right ventricular systolic function and prediction of RVD in the critically ill patients by comparison with other echocardiographic parameters.

METHODS

We conducted an observational, prospective clinical study in 100 patients hospitalized in the intensive care unit. TAPSE, doppler tissue imaging-derived tricuspid lateral annular systolic velocity (DTI-S´ wave), two-dimensional fraction area change (2D FAC) and DTI-right ventricular index of myocardial performance (DTI-RIMP) were measured by transthoracic echocardiography. A subcostal four-chamber view was recorded for sTAPSE measurement. For that purpose, the cursor of AMM was aligned along the direction of the tricuspid lateral annulus movement and the amplitude of the movement was measured.

RESULTS

In a group of patients aged 64±16 years with a 31% prevalence of RVD we identified strong correlation between TAPSE and sTAPSE (r=0.963, P<0.001). sTAPSE correlated well with other measures of right ventricular systolic function (DTI-S´ wave: r=0.765; 2D FAC: r=0.701; DTI-RIMP: r=-0.661, P<0.001, respectively). The value of sTAPSE ≤15 mm predicted the presence of RVD defined by TAPSE with a sensitivity of 94.7% and specificity of 100.0%.

CONCLUSIONS

The sTAPSE measured by AMM in a population of critically ill patients has been found to be a reliable parameter of right ventricular systolic function and predicted RVD with high reliability.

Perioperative echocardiography-guided hemodynamic therapy in high-risk patients: a practical expert approach of hemodynamically focused echocardiography

The number of high-risk patients undergoing surgery is growing. To maintain adequate hemodynamic functioning as well as oxygen delivery to the vital organs (DO2) amongst this patient population, a rapid assessment of cardiac functioning is essential for the anesthesiologist. Pinpointing any underlying cardiovascular pathophysiology can be decisive to guide interventions in the intraoperative setting. Various techniques are available to monitor the hemodynamic status of the patient, however due to intrinsic limitations, many of these methods may not be able to directly identify the underlying cause of cardiovascular impairment. Hemodynamic focused echocardiography, as a rapid diagnostic method, offers an excellent opportunity to examine signs of filling impairment, cardiac preload, myocardial contractility and the function of the heart valves. We thus propose a 6-step-echocardiographic approach to assess high-risk patients in order to improve and maintain perioperative DO2. The summary of all echocardiographic based findings allows a differentiated assessment of the patient's cardiovascular function and can thus help guide a (patho)physiological-orientated and individualized hemodynamic therapy.

[Perioperative optimization using hemodynamically focused echocardiography in high-risk patients-A practice guide]

BACKGROUND

The number of high-risk patients undergoing surgery is steadily increasing. In order to maintain and, if necessary, optimize perioperative hemodynamics as well as the oxygen supply to the organs (DO₂) in this patient population, a timely assessment of cardiac function and the underlying pathophysiological causes of hemodynamic instability is essential for the anesthesiologist. A variety of hemodynamic monitoring procedures are available for this purpose; however, due to method-immanent limitations they are often not able to directly identify the underlying cause of cardiovascular impairment.

OBJECTIVE

To present a stepwise algorithm for a perioperative echocardiography-based hemodynamic optimization in noncardiac surgery high-risk patients. In this context, echocardiography on demand according to international guidelines can be performed under certain conditions (hemodynamic instability, nonresponse to hemodynamic treatment) as well as in the context of a planned intraoperative procedure, mostly as a transesophageal echocardiography.

METHODS AND RESULTS

Hemodynamically focused echocardiography as a rapidly available bedside method, enables the timely diagnosis and assessment of cardiac filling obstructions, volume status and volume response, right and left heart function, and the function of the heart valves.

CONCLUSION

Integrating all echocardiographic findings in a differentiated assessment of the patient's cardiovascular function enables a (patho)physiologically oriented and individualized hemodynamic treatment.