Assessing left ventricular systolic function in shock: evaluation of echocardiographic parameters in intensive care

Evaluation of left ventricular ejection fraction by a new automatic tool on a pocket ultrasound device: Concordance study with cardiac magnetic resonance imaging

INTRODUCTION

Assessment of left ventricular ejection fraction (LVEF) is one of the primary objectives of echocardiography. The gold standard assessment technique in emergency medicine is eyeballing. A new tool is now available on pocket ultrasound devices (PUD): automatic LVEF. The primary aim of this study was to evaluate the concordance between LVEF values estimated by automatic LVEF with PUD and by cardiac magnetic resonance imaging (MRI).

MATERIALS

This was a prospective, monocentric, and observational study. All adult patients with an indication for cardiac MRI underwent a point-of-care ultrasound. Blinded to the MRI results, the emergency physician assessed LVEF using the automatic PUD tool and by visual evaluation.

RESULTS

Sixty patients were included and analyzed. Visual estimation of LVEF was feasible for all patients and automatic evaluation for 52 (87%) patients. Lin's concordance correlation coefficient between automatic ejection fraction with PUD and by cardiac MRI was 0.23 (95% CI, 0.03-0.40).

CONCLUSION

Concordance between LVEF estimated by the automatic ejection fraction with PUD and LVEF estimated by MRI was non-existent.

Dynamic changes of hepatic vein Doppler velocities predict preload responsiveness in mechanically ventilated critically ill patients

BACKGROUND

Assessment of dynamic parameters to guide fluid administration is one of the mainstays of current resuscitation strategies. Each test has its own limitations, but passive leg raising (PLR) has emerged as one of the most versatile preload responsiveness tests. However, it requires real-time cardiac output (CO) measurement either through advanced monitoring devices, which are not routinely available, or echocardiography, which is not always feasible. Analysis of the hepatic vein Doppler waveform change, a simpler ultrasound-based assessment, during a dynamic test such as PLR could be useful in predicting preload responsiveness. The objective of this study was to assess the diagnostic accuracy of hepatic vein Doppler S and D-wave velocities during PLR as a predictor of preload responsiveness.

METHODS

Prospective observational study conducted in two medical-surgical ICUs in Chile. Patients in circulatory failure and connected to controlled mechanical ventilation were included from August to December 2023. A baseline ultrasound assessment of cardiac function was performed. Then, simultaneously, ultrasound measurements of hepatic vein Doppler S and D waves and cardiac output by continuous pulse contour analysis device were performed during a PLR maneuver.

RESULTS

Thirty-seven patients were analyzed. 63% of the patients were preload responsive defined by a 10% increase in CO after passive leg raising. A 20% increase in the maximum S wave velocity after PLR showed the best diagnostic accuracy with a sensitivity of 69.6% (49.1-84.4) and specificity of 92.8 (68.5-99.6) to detect preload responsiveness, with an area under curve of receiving operator characteristic (AUC-ROC) of 0.82 ± 0.07 (p = 0.001 vs. AUC-ROC of 0.5). D-wave velocities showed worse diagnostic accuracy.

CONCLUSIONS

Hepatic vein Doppler assessment emerges as a novel complementary technique with adequate predictive capacity to identify preload responsiveness in patients in mechanical ventilation and circulatory failure. This technique could become valuable in scenarios of basic hemodynamic monitoring and when echocardiography is not feasible. Future studies should confirm these results.

Diagnostic accuracy of left ventricular outflow tract velocity time integral versus inferior vena cava collapsibility index in predicting post-induction hypotension during general anesthesia: an observational study

BACKGROUND

Point of care ultrasound (POCUS) is being explored for dynamic measurements like inferior vena cava collapsibility index (IVC-CI) and left ventricular outflow tract velocity time integral (LVOT-VTI) to guide anesthesiologists in predicting fluid responsiveness in the preoperative period and in treating post-induction hypotension (PIH) with varying accuracy.

METHODS

In this prospective, observational study on included 100 adult patients undergoing elective surgery under general anesthesia, the LVOT-VTI and IVC-CI measurements were performed in the preoperative room 15 minutes prior to surgery, and PIH was measured for 20 minutes in the post-induction period.

RESULTS

The incidence of PIH was 24%. The area under the curve, sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of the two techniques at 95% confidence interval was 0.613, 30.4%, 93.3%, 58.3%, 81.4%, 73.6% for IVC-CI and 0.853, 83.3%, 80.3%, 57.1%, 93.8%, 77.4% for LVOT-VTI, respectively. In multivariate analysis, the cutoff value for IVC-CI was >51.5 and for LVOT-VTI it was ≤17.45 for predicting PIH with odd ratio [OR] of 8.491 (P=0.025) for IVCCI and OR of 17.427 (P<0.001) for LVOT. LVOT-VTI assessment was possible in all the patients, while 10% of patients were having poor window for IVC measurements.

CONCLUSIONS

We recommend the use of POCUS using LVOT-VTI or IVC-CI to predict PIH, to decrease the morbidity of patients undergoing surgery. Out of these, we recommend LVOT-VTI measurements as it has showed a better diagnostic accuracy (77.4%) with no failure rate.

Exploring the Applicability of Pre-Anesthetic Cardiac POCUS in Unexpected Conditions: Could it be Helpful?

Formal preoperative echocardiography has traditionally been recommended when there is substantial cardiovascular disease without recent follow up, unexplained dyspnea, a functional class less than 4 METS or a Duke Activity Status Index less than 34. However, it is important to note that certain patients may present with a variety of cardiac abnormalities due to their preexisting condition or multiple treatments, and these individuals warrant consideration. The objective of pre-anesthetic cardiac POCUS is to provide clinical information in a timely manner. Although it does not aim to replace conventional echocardiography, cardiac POCUS can undoubtedly assist anesthesia practitioners in identifying asymptomatic and potentially hazardous conditions, allowing for more accurate risk allocation and individualized patient care.

Reliability of point-of-care ultrasound to evaluate fluid tolerance performed by critical care residents

BACKGROUND

Patients with hypotension usually receive intravenous fluids, but only 50% will respond to fluid administration. We aimed to assess the intra and interobserver agreement to evaluate fluid tolerance through diverse ultrasonographic methods.

METHODS

We prospectively included critically ill patients on mechanical ventilation. One trained intensivist and two intensive care residents obtained the left ventricular outflow tract velocity-time integral (VTI) variability, inferior vena cava (IVC) distensibility index, internal jugular vein (IJV) distensibility index, and each component of the venous excess ultrasound (VExUS) system. We obtained the intraclass correlation coefficient (ICC) and Gwet's first-order agreement coefficient (AC1), as appropriate.

RESULTS

We included 32 patients. In-training observers were unable to assess the VTI-variability in two patients. The interobserver agreement was moderate to evaluate the IJV-distensibility index (AC1 0.54, CI 95% 0.29-0.80), fair to evaluate VTI-variability (AC1 0.39, CI 95% 0.12-0.66), and absent to evaluate the IVC-distensibility index (AC1 0.19, CI 95% - 0.07 to 0.44). To classify patients according to their VExUS grade, the intraobserver agreement was good, and the interobserver agreement was moderate (AC1 0.52, CI 95% 0.34-0.69).

CONCLUSIONS

Point-of-care ultrasound is frequently used to support decision-making in fluid management. However, we observed that the VTI variability and IVC-distensibility index might require further training of the ultrasound operators to be clinically useful. Our findings suggest that the IJV-distensibility index and the VExUS system have acceptable reproducibility among in-training observers.

CARDIAC OUTPUT IN CRITICALLY ILL PATIENTS CAN BE ESTIMATED EASILY AND ACCURATELY USING THE MINUTE DISTANCE OBTAINED BY PULSED-WAVE DOPPLER

ABSTRACT

Background: Cardiac output (CO) assessment is essential for management of patients with circulatory failure. Among the different techniques used for their assessment, pulsed-wave Doppler cardiac output (PWD-CO) has proven to be an accurate and useful tool. Despite this, assessment of PWD-CO could have some technical difficulties, especially in the measurement of left ventricular outflow tract diameter (LVOTd). The use of a parameter such as minute distance (MD) which avoids LVOTd in the PWD-CO formula could be a simple and useful way to assess the CO in critically ill patients. Therefore, the aim of this study was to evaluate the correlation and agreement between PWD-CO and MD. Methods: A prospective and observational study was conducted over 2 years in a 30-bed intensive care unit (ICU). Adult patients who required CO monitoring were included. Clinical echocardiographic data were collected within the first 24 h and at least once more during the first week of ICU stay. PWD-CO was calculated using the average value of three LVOTd and left ventricular outflow tract velocity-time integral (LVOT-VTI) measurements, and heart rate. Minute distance was obtained from the product of LVOT-VTI × heart rate. Pulsed-wave Doppler cardiac output was correlated with MD using linear regression. Cardiac output was quantified from the MD using the equation defined by linear regression. Bland-Altman analysis was also used to evaluate the level of agreement between CO calculated from MD (MD-CO) and PWD-CO. The percentage error was calculated. Results: A total of 98 patients and 167 CO measurements were analyzed. Sixty-seven (68%) were male, the median age was 66 years (interquartile range [IQR], 53-75 years), and the median Acute Physiology and Chronic Health Evaluation II score was 22 (IQR, 16-26). The most common cause of admission was shock in 81 patients (82.7%). Sixty-nine patients (70.4%) were mechanically ventilated, and 68 (70%) required vasoactive drugs. The median CO was 5.5 L/min (IQR, 4.8-6.6 L/min), and the median MD was 1,850 cm/min (IQR, 1,520-2,160 cm/min). There was a significant correlation between PWD-CO and MD-CO in the general population ( R2 = 0.7; P < 0.05). This correlation improved when left ventricular ejection fraction (LVEF) was less than 60% ( R2 = 0.85, P < 0.05). Bland-Altman analysis showed good agreement between PWD-CO and MD-CO in the general population, the median bias was 0.02 L/min, the limits of agreement were -1.92 to +1.92 L/min. The agreement was better in patients with LVEF less than 60% with a median bias of 0.005 L/min and limits of agreement of -1.56 to 1.55 L/min. The percentage error was 17% in both cases. Conclusion: Measurement of MD in critically ill patients provides a simple and accurate estimate of CO, especially in patients with reduced or preserved LVEF. This would allow earlier cardiovascular assessment in patients with circulatory failure, which is of particular interest in difficult clinical or technical conditions.

Echocardiographic hemodynamic assessment in decompensated cirrhosis: comparison between Intensivists and Gastroenterologists

BACKGROUND & AIMS

Ascites is a frequent complication of cirrhosis. In intensive care units, initial hemodynamic assessment is frequently performed by echocardiography. This study evaluated the feasibility and usefulness of early hemodynamic assessment in the gastroenterology ward.

METHODS

This observational cohort study prospectively included all patients admitted to a teaching hospital's gastroenterology unit for decompensated cirrhosis. A gastroenterologist with minimal training and an intensivist both performed an echocardiography exam. The primary outcome was inter-rater agreement and reliability for three echocardiography parameters: visual LVEF (Left Ventricular Ejection Fraction), subaortic VTI (velocity time integral) and E wave velocity. Secondary outcomes were agreement for presence of pleural effusion, description of 3 hemodynamics profiles (hypovolemic, hyperkinetic and intermediate), and 28-day mortality.

RESULTS

From March 2018 to March 2020, 53 patients were included. The median age was 62 years and 81% were men. Patients presented mostly advanced liver disease, with 43% Child-Pugh C and median MELD score of 15.2. The limits of agreement between intensivists and gastroenterologists for subaortic VTI were - 6.6 to 7.2 cm, and ranged from - 0.6 to 0.37 m.s-1 for E wave velocity. Clinically significant differences between intensivists and gastroenterologists were found in 22% for subaortic VTI and 24.5% for E wave velocity. Reliability was good for subaortic VTI (ICC: 0.79, 95% CI [0.58; 0.9;]) and moderate for E wave velocity (0.53, 95% CI [0.19; 0.74]). The three hemodynamics profiles had different prognosis, with a 28-day mortality for Hypovolemic, Intermediate and Hyperkinetic group of 31, 18, and 4%, respectively.

CONCLUSION

Reliability of hemodynamic assessment by gastroenterologists was good, while agreement was unsatisfactory, advocating for further training. Transthoracic echocardiography can differentiate hypovolemia from hyperkinetic states. The role of transthoracic echocardiography in managing decompensated cirrhosis requires further study.

CLINICAL TRIAL NUMBER

NCT03650660.

Correlation between tissue Doppler-derived left ventricular systolic velocity (S') and left ventricle ejection fraction in sepsis and septic shock: a retrospective cohort study

BACKGROUND

Tissue Doppler-derived left ventricular systolic velocity (mitral S') has shown excellent correlation to left ventricular ejection fraction (LVEF) in non-critically patients. However, their correlation in septic patients remains poorly understood and its impact on mortality is undetermined. We investigated the relationship between mitral S' and LVEF in a large cohort of critically-ill septic patients.

METHODS

We conducted a retrospective cohort study between 01/2011 and 12/2020. All adult patients (≥ 18 years) who were admitted to the medical intensive care unit (MICU) with sepsis and septic shock that underwent a transthoracic echocardiogram (TTE) within 72 h were included. Pearson correlation test was used to assess correlation between average mitral S' and LVEF. Pearson correlation was used to assess correlation between average mitral S' and LVEF. We also assessed the association between mitral S', LVEF and 28-day mortality.

RESULTS

2519 patients met the inclusion criteria. The study population included 1216 (48.3%) males with a median age of 64 (IQR: 53-73), and a median APACHE III score of 85 (IQR: 67, 108). The median septal, lateral, and average mitral S' were 8 cm/s (IQR): 6.0, 10.0], 9 cm/s (IQR: 6.0, 10.0), and 8.5 cm/s (IQR: 6.5, 10.5), respectively. Mitral S' was noted to have moderate correlation with LVEF (r = 0.46). In multivariable logistic regression analysis, average mitral S' was associated with an increase in both 28-day ICU and in-hospital mortality with odds ratio (OR) 1.04 (95% CI 1.01-1.08, p = 0.02) and OR 1.04 (95% CI 1.01-1.07, p = 0.02), respectively.

CONCLUSIONS

Even though mitral S' and LVEF may be related, they are not exchangeable and were only found to have moderate correlation in this study. LVEF is U-shaped, while mitral S' has a linear relation with 28-day ICU mortality. An increase in average mitral S' was associated with higher 28-day mortality.

The use of bedside echocardiography in the care of critically ill patients - a joint consensus document of the Associação de Medicina Intensiva Brasileira, Associação Brasileira de Medicina de Emergência and Sociedade Brasileira de Medicina Hospitalar. Part 2 - Technical aspects

Echocardiography in critically ill patients has become essential in the evaluation of patients in different settings, such as the hospital. However, unlike for other matters related to the care of these patients, there are still no recommendations from national medical societies on the subject. The objective of this document was to organize and make available expert consensus opinions that may help to better incorporate echocardiography in the evaluation of critically ill patients. Thus, the Associação de Medicina Intensiva Brasileira, the Associação Brasileira de Medicina de Emergência, and the Sociedade Brasileira de Medicina Hospitalar formed a group of 17 physicians to formulate questions relevant to the topic and discuss the possibility of consensus for each of them. All questions were prepared using a five-point Likert scale. Consensus was defined a priori as at least 80% of the responses between one and two or between four and five. The consideration of the issues involved two rounds of voting and debate among all participants. The 27 questions prepared make up the present document and are divided into 4 major assessment areas: left ventricular function, right ventricular function, diagnosis of shock, and hemodynamics. At the end of the process, there were 17 positive (agreement) and 3 negative (disagreement) consensuses; another 7 questions remained without consensus. Although areas of uncertainty persist, this document brings together consensus opinions on several issues related to echocardiography in critically ill patients and may enhance its development in the national scenario.

Comparison of visual estimation and quantitative measurement of left ventricular ejection fraction in untrained perioperative echocardiographers

BACKGROUND

Perioperative evaluation of the left ventricular systolic function is essential information to help diagnose and manage life-threatening perioperative emergencies. Although quantifying the left ventricular ejection fraction (LVEF) is recommended to determine the left ventricular function, it may not always be feasible in emergency perioperative settings. This study compared the visual estimation of LVEF (eyeballing) by noncardiac anesthesiologists with the quantitative LVEF measured using a modified Simpson's biplane method.

METHODS

Transesophageal echocardiographic (TEE) studies of 35 patients were selected and 3 different echocardiographic views (the mid-esophageal four chamber view, the mid-esophageal two chamber view, and the transgastric mid-papillary short axis view) were recovered from each study and displayed in random order. Two cardiac anesthesiologists certified in perioperative echocardiography independently measured LVEF using the modified Simpson method and categorized LVEF into five grades: hyperdynamic LVEF, normal, mildly reduced LVEF, moderately reduced LVEF and severely reduced LVEF. Seven noncardiac anesthesiologists with limited experience in echocardiography also reviewed the same TEE studies and estimated the LVEF and graded LV function. The precision of the LV function classification and the correlation between visual estimation of LVEF and quantitative LVEF were calculated. The agreement of measurements between the two methods was also assessed.

RESULTS

Pearson's correlation between the LVEF estimated by the participants and the quantitative LVEF using the modified Simpson method was 0.818 (p < 0.001). Of a total of 245 responses, 120 (49.0%) responses were correct grading of the LV function. Participants were able to classify the LV function more accurately in the LV function grades 1 and 5 (65.3%). The 95% level of agreement of the Bland-Altman method was - 11.3-24.5. -21.9-22.6, - 23.1-26.5, - 20.5-22.0 and - 26.6-11.1 for LV grade 1 to 5, respectively.

CONCLUSION

Visual estimation of LVEF in perioperative TEE has acceptable accuracy in untrained echocardiographers and can be used for rescue TEE.

Changes of cardiac output and velocity time integral in blood return at the end of renal replacement therapy predict fluid responsiveness in critically Ill patients with acute circulatory failure

OBJECTIVES

To observe if blood return, also defined as the blood infusion test (BIT) could predict fluid responsiveness in critically ill patients with acute circulatory failure and renal replacement therapy (RRT).

METHODS

This was a single-center, prospective, diagnostic accuracy study. Before BIT, the passive leg raise test (PLRT) was performed to record the change of cardiac output (ΔCO) by pulse contour analysis, and ΔCO >  = 10% was defined as the fluid responder. Meanwhile, the change in velocity time integral (ΔVTI) was recorded by ultrasound. Later, the ΔCO and ΔVTI during BIT were recorded 5-10 min after PLRT. The receiver-operating characteristic curves of ΔCO and ΔVTI of BIT were performed in predicting the fluid responder defined by PLRT.

RESULTS

A total of 43 patients with acute circulatory failure undergoing RRT were enrolled in the present study, and 25 patients (58.1%) were recognized as responders during PLRT. According to the receiver-operating characteristic curves, the cutoff value of ΔCO was 10% and ΔVTI was 9% during BIT with the area under curve of 0.96 and 0.94, respectively.

CONCLUSIONS

BIT in RRT could identify fluid responsiveness in critically ill patients with shock.

TRIAL REGISTRATION

ChiCTR-DDD-17010534. Registered on 30/01/2017 (retrospective registration).

The Role of Left Ventricular Ejection Fraction and Left Ventricular Outflow Tract Velocity-Time Integral in Assessing Cardiovascular Impairment in Septic Shock

Background: the role of echocardiography in septic shock remains controversial, since depressed cardiac afterload may overestimate left ventricular (LV) systolic performance and mask septic cardiomyopathy (SC). We hypothesized that afterload-adjusted LV ejection fraction (LVEF) and LV outflow tract velocity-time integral (VTI) values for given systemic vascular resistances (SVR) could provide novel insights into recognizing and stratifying the severity of SC. Methods: in this observational, monocentric study, we prospectively included 14 mechanically-ventilated patients under septic-shock who all had a Pulse index Continuous Cardiac Output (PiCCO) system in place for hemodynamic monitoring. Echocardiographic and PiCCO longitudinal examinations (71 measurements overall) were performed simultaneously at the onset of septic shock and every 12 h for 60 h overall. Results: VTI-derived stroke volume (SV) and cardiac output (CO) were significantly correlated with PiCCO measurements (r ≥ 0.993, both p < 0.001). LVEF and VTI showed linear and exponential inverse correlation to SVR (R2 = 0.183 vs. 0.507 and p < 0.001 vs. p < 0.001, respectively). The equations LVEF = 86.168 − 0.011 × SVR and VTI = 41.23 × e(−0.0005×SVR) were found to provide “predicted” values for given SVR. Measured to predicted LVEF ratios (for given SVR), the afterload-adjusted LVEF defined the severity of SC (mild ≥ 90%, 80% ≤ moderate < 90% and severe < 80%). Mild SC demonstrated normal/supra-normal LVEF, normal VTI and SVR. Moderate SC showed lower LVEF and SVR, yet increased LV end-diastolic volume (LVEDV), VTI, SV and CO compared with mild SC (all p < 0.05). Severe SC was distinguished from moderate SC by markedly reduced LVEF, LVEDV, VTI, SV, CO and significantly increased SVR (all p < 0.05). LVEF and VTI decreased over time in mild SC, LVEF decreased in moderate SC, and LVEF and VTI increased over time in severe SC (p ≤ 0.038). LVEF and VTI demonstrated significant performance in identifying severe SC [cut-off < 61.5%, area under the curve (AUC) = 1 ± 0.0, sensitivity/specificity = 100/100, p < 0.001 vs. cut-off < 17.9 cm, AUC = 0.882 ± 0.042, sensitivity/specificity = 80/77, p < 0.001, respectively]. VTI but not LVEF demonstrated significant diagnostic performance in identifying both SVR < 800 dynes·s·cm−5 and SVR > 1500 dynes·s·cm−5 (cut-off > 24.46 cm, AUC = 0.889 ± 0.049, sensitivity/specificity = 75/100, p < 0.001; cut-off < 16.8, AUC = 0.0.857 ± 0.082, sensitivity/specificity = 83/86, p = 0.002, respectively).Conclusions: our study suggests that ICU bedside echocardiographic assessment of LVEF, VTI and their adjusted to corresponding SVR values provides valuable insights for the comprehension of SC phenotypes, underlying vasoplegia and cardiac output fluctuations in septic shock.

Serial changes in left ventricular myocardial deformation in sepsis or septic shock using three-dimensional and two-dimensional speckle tracking echocardiography

Background

This study aimed to investigate the serial changes in left ventricular (LV) myocardial deformation in patients with sepsis using three-dimensional (3D) and two-dimensional (2D) speckle tracking echocardiography (STE).

Methods

In this single-center, prospective, and observational study, we included 59 patients diagnosed with sepsis or septic shock in the intensive care unit and 40 healthy controls. Left ventricular ejection fraction (LVEF), left ventricular global longitudinal strain (GLS), and global circumferential strain (GCS) assessed by 3D STE and 2D STE were obtained on the first, third, fifth, seventh to the tenth day after sepsis or septic shock.

Results

In patients with sepsis or septic shock, 3D and 2D LVEF were not different at each time point. GLS and GCS obtained by 3D STE and 2D STE decreased on the first day compared with the healthy group (all P < 0.01). Compared with the values on the first day, GLS and GCS further decreased on the third day, while 3D and 2D LVEF did not differ. 3D and 2D STE strains were lowest on the third day and gradually improved on the seventh to the tenth day compared with values on the third day. When compared with values on the first day, 3D and 2D GLS gradually improved on the seventh to the tenth day, whereas 3D and 2D GCS on the seventh to the tenth day was not different. Although 3D and 2D STE strains were significantly increased on the seventh to the tenth day, they were not fully recovered to normality.

Conclusion

Although patients with sepsis or septic shock demonstrated gradual improvements in 3D and 2D STE parameters during the ten-day period, LV myocardial strain was not fully recovered to normality by the seventh to the tenth days. 3D and 2D strain imaging, used as a helpful tool for monitoring the evolution of myocardial deformation, can provide clinicians with a useful additional imaging parameter.

Artificial intelligence (AI) versus expert: A comparison of left ventricular outflow tract velocity time integral (LVOT-VTI) assessment between ICU doctors and an AI tool

PURPOSE

The application of point of care ultrasound (PoCUS) in medical education is a relatively new course. There are still great differences in the existence, quantity, provision, and depth of bedside ultrasound education. The left ventricular outflow tract velocity time integral (LVOT-VTI) has been successfully used in several studies as a parameter for hemodynamic management of critically ill patients, especially in the evaluation of fluid responsiveness. While LVOT-VTI has been broadly used, valuable applications using artificial intelligence (AI) in PoCUS is still limited. We aimed to identify the degree of correlation between auto LVOT-VTI and the manual LVOT-VTI acquired by PoCUS trained ICU doctors.

METHODS

Among the 58 ICU doctors who attended PoCUS training from 1 September 2019 to 30 November 2020, 46 ICU doctors who trained for more than 3 months were enrolled. At the end of PoCUS training, each of the enrolled ICU doctors acquired echocardiography parameters of a new ICU patient in 2 h after new patient was admitted. One of the two bedside expert sonographers would take standard echocardiogram of new ICU patients within 24 h. For ICU doctors, manual LVOT-VTI was obtained for reference and auto LVOT-VTI was calculated instantly by using an AI software tool. Based on the image quality of the auto LVOT-VTI, ICU patients was separated into ideal group (n = 31) and average group (n = 15).

RESULTS

Left ventricular end-diastolic dimension (LVEDd, p = 0.1028), left ventricular ejection fraction (LVEF, p = 0.3251), left atrial dimension (LA-d, p = 0.0962), left ventricular E/A ratio (p = 0.160), left ventricular wall motion (p = 0.317) and pericardial effusion (p = 1) had no significant difference between trained ICU doctors and expert sonographer. ICU patients in average group had greater sequential organ failure assessment (SOFA) score (7.33 ± 1.58 vs. 4.09 ± 0.57, p = 0.022) and lactic acid (3.67 ± 0.86 mmol/L vs. 1.46 ± 0.12 mmol/L, p = 0.0009) with greater value of LVEDd (51.93 ± 1.07 vs. 47.57 ± 0.89, p = 0.0053), LA-d (39.06 ± 1.47 vs. 35.22 ± 0.98, p = 0.0334) and percentage of decreased wall motion (p = 0.0166) than ideal group. There were no significant differences of δLVOT-VTI (|manual LVOT-VTI - auto LVOT-VTI|/manual VTI*100%) between the two groups (8.8% ± 1.3% vs. 10% ± 2%, p = 0.6517). Statistically, significant correlations between manual LVOT-VTI and auto LVOT-VTI were present in the ideal group (R2  = 0.815, p = 0.00) and average group (R2  = 0.741, p = 0.00).

CONCLUSIONS

ICU doctors could achieve the satisfied level of expertise as expert sonographers after 3 months of PoCUS training. Nearly two thirds of the enrolled ICU doctors could obtain the ideal view and one third of them could acquire the average view. ICU patients with higher SOFA scores and lactic acid were less likely to acquire the ideal view. Manual and auto LVOT-VTI had statistically significant agreement in both ideal and average groups. Auto LVOT-VTI in ideal view was more relevant with the manual LVOT-VTI than the average view. AI might provide real-time guidance among novice operators who lack expertise to acquire the ideal standard view.

Stroke Volume Determination by Echocardiography

Basic critical care echocardiography emphasizes two-dimensional (2D) findings, such as ventricular function, inferior vena cava size, and pericardial assessment, while generally excluding quantitative findings and Doppler-based techniques. Although this approach offers advantages, including efficiency and expedited training, it complicates attempts to understand the hemodynamic importance of any 2D abnormalities detected. Stroke volume (SV), as the summative event of the cardiac cycle, is the most pragmatic available indicator through which a clinician can rapidly determine, no matter the 2D findings, whether aberrant cardiac physiology is contributing to the state of shock. An estimate of SV allows 2D findings to be placed into better context in terms of both hemodynamic significance and acuity. This article describes the technique of SV determination, reviews common confounding factors and pitfalls, and suggests a systematic approach for using SV measurements to help integrate important 2D findings into the clinical context.

Left Ventricle Outflow Tract Velocity-Time Index and Right Ventricle to Left Ventricle Ratio as Predictors for in Hospital Outcome in Intermediate-Risk Pulmonary Embolism

Accurate estimation of risk with both imaging and biochemical parameters in intermediate risk pulmonary embolism (PE) remains challenging. The aim of the study was to evaluate echocardiographic parameters that reflect right and left heart hemodynamic as predictors of adverse events in intermediate risk PE. This was a retrospective observational study on patients with computed tomography pulmonary angiography diagnosis of PE admitted at Cardiology department of the Clinical Emergency Hospital of Oradea, Romania between January 2018—December 2021. Echocardiographic parameters obtained at admission were studied as predictors of in hospital adverse events. The following adverse outcomes were registered: death, resuscitated cardiac arrest, hemodynamic deterioration and need of rescue thrombolysis. An adverse outcome was present in 50 patients (12.62%). PE related death was registered in 17 patients (4.3%), resuscitated cardiac arrest occurred in 6 patients (1.51%). Another 20 patients (5.05%) required escalation of therapy with thrombolysis and 7 (1.76%) patients developed haemodynamic instability. Echocardiographic independent predictors for in hospital adverse outcome were RV/LV ≥ 1 (HR = 3.599, 95% CI 1.378−9.400, p = 0.009) and VTI ≤ 15 mm (HR = 11.711, 95% CI 4.336−31.633, p < 0.001). The receiver operator curve renders an area under curve for LVOT VTI ≤ 15 mm of 0.792 (95% CI 0.719−0.864, p < 0.001) and for a RV/LV ≥ 1 of 0.746 (95% CI 0.671−0.821, p < 0.001). A combined criterion (LVOT VTI ≤ 15 and RV/LV ≥ 1) showed a positive predictive value of 75% and a negative predictive value of 95% regarding in hospital adverse outcomes. Low LVOT VTI and increased RV/LV are useful for identifying normotensive patients with PE at risk for short term adverse outcomes. Combining an LVOT VTI ≤ 15 cm with a RV/LV ≥ 1 can identify with increased accuracy PE patients with impending risk of clinical deterioration.

Echocardiography in a critical care unit: A contemporary review

INTRODUCTION

Echocardiography is a rapid, noninvasive, and complete cardiac assessment tool for patients with hemodynamic instability. This review provides an overview of the evidence for current practices in critical care units (CCUs), incorporating the use of echocardiography in different etiologies of shock.

AREAS COVERED

: Relevant articles were extracted after searching on databases by two reviewers and incorporated in this review in a narrative style.

EXPERT OPINION

: In an acute scenario, a basic echocardiographic study yields prompt diagnosis, allowing for the initiation of treatment. The most common pathologies in shocked patients are identified promptly using two-dimensional (2D) and M-mode echocardiography. A more comprehensive assessment can follow after patients have been stabilized. There are four types of shock: (i) cardiogenic shock, (ii) hypovolemic shock, (iii) obstructive shock, and (iv) septic shock. All of them can be readily identified by echocardiography. As echocardiography is increasingly being used in an intensive care setting, its applications and evidence base should be expanded by randomized controlled trials to demonstrate patient outcomes in critical care.

Proposal criteria of paradoxical low-flow low-gradient aortic stenosis for predicting prognosis in patients undergoing transcatheter aortic valve implantation

BACKGROUND

Paradoxical low-flow, low-gradient (PLF-LG) aortic stenosis (AS) is associated with poor prognosis in patients undergoing transcatheter aortic valve implantation (TAVI). This study aimed to verify the conventional criteria of PLF-LG AS (left ventricular ejection fraction [LVEF] > 50%, mean aortic valve pressure gradient [AVPG] < 40 mm Hg and stroke volume index [SVI] < 35 ml/m² by measuring Doppler method) compatible for predicting prognosis in patients undergoing TAVI.

MATERIALS AND METHODS

A total of 128 consecutive patients who underwent TAVI for AS with LVEF > 50% were enrolled. The primary endpoint was the hospital readmission due to heart failure (HRHF) and the secondary endpoint was all-cause mortality after hospital discharge. The patients were classified by both the conventional criteria of PLF-LG AS and the proposal criteria of PLF-LG AS if mean aortic valve pressure gradient (AVPG) < 40 mmHg and SVI by measuring Simpson's method < cut off value based on the ROC curve for predicting HRHF.

RESULTS

According to the conventional criteria, only 6 patients were diagnosed with PLF-LG AS. However, according to the proposal criteria, 16 patients were diagnosed with PLF-LG AS. Fourteen patients developed HRHF during the follow-up period after TAVI. Based on the ROC curves, SVI by measuring Simpson's method (cut off value = 25 ml/m²) had higher sensitivity and specificity for predicting HRHF (AUC = 0.74, p = 0.0013) than SVI by measuring Doppler method (AUC = 0.63, p = 0.045). The multivariate analysis revealed that PLF-LG AS defined by the proposal criteria (HR: 5.25; 95% CI: 1.60-17.16; p = 0.0073) but not by the conventional criteria was independently associated with HRHF. PLF-LG AS defined by the conventional criteria and the proposal criteria were not associated with all-cause mortality in the univariate analysis.

CONCLUSIONS

Our results demonstrated that new criteria of PLF-LG AS defined as SVI < 25 ml/m² measured by Simpson's method could predict HRHF in patients with severe AS who underwent TAVI.

Can Thoracic Ultrasound on Admission Predict the Outcome of Critically Ill Patients with SARS-CoV-2? A French Multi-Centric Ancillary Retrospective Study

Introduction

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreaks have led to massive admissions to intensive care units (ICUs). An ultrasound examination of the thorax is widely performed on admission in these patients. The primary objective of our study was to assess the performance of the lung ultrasound score (LUS) on ICU admission to predict the 28-day mortality rate in patients with SARS-CoV-2. The secondary objective was to asses the performance of thoracic ultrasound and biological markers of cardiac injury to predict mortality.

Methods

This multicentre, retrospective, observational study was conducted in six ICUs of four university hospitals in France from 15 March to 3 May 2020. Patients admitted to ICUs because of SARS-CoV-2-related acute respiratory failure and those who received an LUS examination at admission were included. The area under the receiver-operating characteristics (ROC) curve was determined for the LUS score to predict the 28-day mortality rate. The same analysis was performed for the Simplified Acute Physiology Score, left ventricular ejection fraction, cardiac output, brain natriuretic peptide and ultra-sensitive troponin levels at admission.

Results

In 57 patients, the 28-day mortality rate was 21%. The area under the ROC curve of the LUS score value on ICU admission was 0.68 [95% CI 0.54–0.82; p = 0.05]. In non-intubated patients on ICU admission (n = 40), the area under the ROC curves was 0.84 [95% CI 0.70–0.97; p = 0.005]. The best cut-off of 22 corresponded to 85% specificity and 83% sensitivity.

Conclusions

LUS scores on ICU admission for SARS-CoV-2 did not efficiently predict the 28-day mortality rate. Performance was better for non-intubated patients at admission. Performance of biological cardiac markers may be equivalent to the LUS score.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12325-021-01702-0.

Left ventricular longitudinal wall fractional shortening accurately predicts longitudinal strain in critically ill patients with septic shock

Background

Left ventricular longitudinal strain (LVLS) may be a sensitive indicator of left ventricular (LV) systolic function in patients with sepsis, but is dependent on high image quality and analysis software. Mitral annular plane systolic excursion (MAPSE) and the novel left ventricular longitudinal wall fractional shortening (LV-LWFS) are bedside echocardiographic indicators of LV systolic function that are less dependent on image quality. Both are sparsely investigated in the critically ill population, and may potentially be used as surrogates for LVLS. We assessed if LVLS may be predicted by LV-LWFS and MAPSE in patients with septic shock. We also assessed the repeatability and inter-rater agreement of LVLS, LV-LWFS and MAPSE measurements.

Results

122 TTE studies from 3 echocardiographic data repositories of patients admitted to ICU with septic shock were retrospectively assessed, of which 73 were suitable for LVLS analysis using speckle tracking. The correlations between LVLS vs. LV-LWFS and LVLS vs. MAPSE were 0.89 (p < 0.001) and 0.81 (p < 0.001) with mean squared errors of 5.8% and 9.1%, respectively. Using the generated regression equation, LV-LWFS predicted LVLS with a high degree of accuracy and precision, with bias and limits of agreement of -0.044 ± 4.7% and mean squared prediction error of 5.8%. Interobserver repeatability was good, with high intraclass correlation coefficients (0.96–0.97), small bias and tight limits of agreement (≤ 4.1% for all analyses) between observers for all measurements.

Conclusions

LV-LWFS may be used to estimate LVLS in patients with septic shock. MAPSE also performed well, but was slightly inferior compared to LV-LWFS in estimating LVLS. Feasibility of MAPSE and LV-LWFS was excellent, as was interobserver repeatability.

Preoperative Point-of-Care Assessment of Left Ventricular Systolic Dysfunction With Transthoracic Echocardiography

BACKGROUND

Left ventricular (LV) systolic dysfunction is an acknowledged perioperative risk factor and should be identified before surgery. Conventional echocardiographic assessment of LV ejection fraction (LVEF) obtained by biplane LV volumes is the gold standard to detect LV systolic dysfunction. However, this modality needs extensive training and is time consuming. Hence, a feasible point-of-care screening method for this purpose is warranted. The aim of this study was to evaluate 3 point-of-care echocardiographic methods for identification of LV systolic dysfunction in comparison with biplane LVEF.

METHODS

One hundred elective surgical patients, with a mean age of 63 ± 12 years and body mass index of 27 ± 4 kg/m2, were consecutively enrolled in this prospective observational study. Transthoracic echocardiography was conducted 1-2 hours before surgery. LVEF was obtained by automatic two-dimensional (2D) biplane ejection fraction (EF) software. We evaluated if Tissue Doppler Imaging peak systolic myocardial velocities (TDISm), anatomic M-mode E-point septal separation (EPSS), and conventional M-mode mitral annular plane systolic excursion (MAPSE) could discriminate LV systolic dysfunction (LVEF <50%) by calculating accuracy, efficiency, correlation, positive (PPV) respective negative predictive (NPV) values, and area under the receiver operating characteristic curve (AUROC) for each point-of-care method.

RESULTS

LVEF<50% was identified in 22% (21 of 94) of patients. To discriminate an LVEF <50%, AUROC for TDISm (mean <8 cm/s) was 0.73 (95% confidence interval [CI], 0.62-0.84; P < .001), with a PPV of 47% and an NPV of 90%. EPSS with a cutoff value of >6 mm had an AUROC 0.89 (95% CI, 0.80-0.98; P < .001), with a PPV of 67% and an NPV of 96%. MAPSE (mean <12 mm) had an AUROC 0.80 (95% CI, 0.70-0.90; P < 0.001) with a PPV of 57% and an NPV of 98%.

CONCLUSIONS

All 3 point-of-care methods performed reasonably well to discriminate patients with LVEF <50%. The clinician may choose the most suitable method according to praxis and observer experience.

The Role of LVOT-VTI Measurement in the Evaluation of Systolic Heart Function in Pulmonary ICU Patients

Introduction:

The detection of cardiac systolic dysfunction is very important for well management of pulmonary critical care patients (PCCPs). However, there is a poor correlation between echocardiographic cardiac systolic function (CSF) parameters and it is not easy to obtain these parameters in PCCPs. Therefore, this cross-sectional observational study was planned for the detection of a more easily obtainable echocardiographic CSF parameter that is well correlated with other CSF parameters in PCCPs.

Materials and Methods:

Total 88 PCCPs were included. Demographic and clinical information and laboratory tests of all patients were recorded. The CSF parameters of the heart were obtained by transthoracic echocardiography with appropriate technique. LVOT-VTI (Left ventricular outflow tract velocity time integral), CO (cardiac output), EPSS (e point septal separation), Left ventricular EF (ejection fraction) and TAPSE (Tricuspid Annular Plane Systolic Excursion) as an indicator of CSF were tried to obtain from all patients. We also calculated sensitivity, specificity, positive and negative predictive values of LVOT-VTI<20 parameters to diagnose heart failure.

Results:

The mean age of the patients was 73±12, 40% were female, 38% were intubated and 52% had COPD. LVOT-VTI, EF, CO, EPSS parameters were obtained in 54(61%), 24(27%), 48(54%), 48(54%) patients, respectively. Decreased LVOT-VTI (<20 cm) was well correlated with decreased EF (<45%) (p=0.001, r=0.77), decreased CO (<5 L/dk) (p=0.03, r=0.64) and decreased TAPSE (<17 mm) (p=0.001, r=0.71). Also, there was good agreement between the EF and LVOTVTI measurements (Kappa:0.78, p:0.001). Sensitivity, specificity, positive and negative predictive values of LVOT-VTI<20 for heart failure were 58, 78, 84, 49, repectively.

Conclusion:

LVOT-VTI is a more easily obtainable and well correlated parameter, which can be used as an indicator of CSF in PCCPs.

Clinical Significances:

The authors believe that LVOT-VTI measurement has good correlation with other echocardiographic systolic function parameters, and its easy measurement in intensive care patients makes it a very useful test for cardiac systolic function evaluation.

A machine learning algorithm supports ultrasound-naïve novices in the acquisition of diagnostic echocardiography loops and provides accurate estimation of LVEF

Left ventricular ejection fraction (LVEF) is the most important parameter in the assessment of cardiac function. A machine-learning algorithm was trained to guide ultrasound-novices to acquire diagnostic echocardiography images. The artificial intelligence (AI) algorithm then estimates LVEF from the captured apical-4-chamber (AP4), apical-2-chamber (AP2), and parasternal-long-axis (PLAX) loops. We sought to test this algorithm by having first-year medical students without previous ultrasound knowledge scan real patients. Nineteen echo-naïve first-year medical students were trained in the basics of echocardiography by a 2.5 h online video tutorial. Each student then scanned three patients with the help of the AI. Image quality was graded according to the American College of Emergency Physicians scale. If rated as diagnostic quality, the AI calculated LVEF from the acquired loops (monoplane and also a "best-LVEF" considering all views acquired in the particular patient). These LVEF calculations were compared to images of the same patients captured and read by three experts (ground-truth LVEF [GT-EF]). The novices acquired diagnostic-quality images in 33/57 (58%), 49/57 (86%), and 39/57 (68%) patients in the PLAX, AP4, and AP2, respectively. At least one of the three views was obtained in 91% of the attempts. We found an excellent agreement between the machine's LVEF calculations from images acquired by the novices with the GT-EF (bias of 3.5% ± 5.6 and r = 0.92, p < 0.001 in the "best-LVEF" algorithm). This pilot study shows first evidence that a machine-learning algorithm can guide ultrasound-novices to acquire diagnostic echo loops and provide an automated LVEF calculation that is in agreement with a human expert.

Assessment of dynamic changes in cardiac function during resuscitation of patients with suspected septic shock: A prospective, observational, cohort study

STUDY OBJECTIVE

To describe changes in cardiac function throughout the course of resuscitation of patients with suspected septic shock.

METHODS

Prospective observational cohort study of Point-of-Care Transthoracic Echocardiograms (TTE) obtained in Emergency Department (ED) patients with a presumed infectious cause of hypotension within one hour of initiating IV fluid resuscitation. Findings of this pre-resuscitation TTE were compared to mid-resuscitation TTE (obtained upon disposition from the ED), and post-resuscitation TTE (obtained after admission to hospital).

RESULTS

22 enrolled patients had a second TTE available for comparison to the initial, pre-resuscitation TTE. 12 patients had a mid-resuscitation TTE and 16 patients had a post-resuscitation TTE. We observed a high incidence of changes on TTE during the clinical course of resuscitation (14/22 [64%]). Patients who developed LV or RV dysfunction during resuscitation were more likely to require vasopressor infusion and ICU admission (Spearman's coefficients [95% CI] of 0.68 [0.36-0.86] and 0.47 [0.04;0.75] respectively). Development of RV dysfunction alone was associated with increased use of positive pressure ventilation and vasopressor infusion (Spearman's coefficients [95% CI] of 0.43 [0;0.72] and 0.47 [0.05,0.75] respectively).

CONCLUSIONS

Cardiac function changes assessed by TTE are common during the resuscitation of patients with septic shock. These changes likely reflect the underlying physiology of patients with septic shock and correlate with need for interventions and higher level of care. Further work is required to characterize these changes and to elucidate how to use these physiologic data to guide management.

Validation of Epworth Richmond's Echocardiography Education Focused Year

Supplemental Digital Content is available in the text.

Rationale for using the velocity-time integral and the minute distance for assessing the stroke volume and cardiac output in point-of-care settings

Background

Stroke volume (SV) and cardiac output (CO) are basic hemodynamic parameters which aid in targeting organ perfusion and oxygen delivery in critically ill patients with hemodynamic instability. While there are several methods for obtaining this data, the use of transthoracic echocardiography (TTE) is gaining acceptance among intensivists and emergency physicians. With TTE, there are several points that practitioners should consider to make estimations of the SV/CO as simplest as possible and avoid confounders.

Main body

With TTE, the SV is usually obtained as the product of the left ventricular outflow tract (LVOT) cross-sectional area (CSA) by the LVOT velocity–time integral (LVOT VTI); the CO results as the product of the SV and the heart rate (HR). However, there are important drawbacks, especially when obtaining the LVOT CSA and thus the impaction in the calculated SV and CO. Given that the LVOT CSA is constant, any change in the SV and CO is highly dependent on variations in the LVOT VTI; the HR contributes to CO as well. Therefore, the LVOT VTI aids in monitoring the SV without the need to calculate the LVOT CSA; the minute distance (i.e., SV × HR) aids in monitoring the CO. This approach is useful for ongoing assessment of the CO status and the patient’s response to interventions, such as fluid challenges or inotropic stimulation. When the LVOT VTI is not accurate or cannot be obtained, the mitral valve or right ventricular outflow tract VTI can also be used in the same fashion as LVOT VTI. Besides its pivotal role in hemodynamic monitoring, the LVOT VTI has been shown to predict outcomes in selected populations, such as in patients with acute decompensated HF and pulmonary embolism, where a low LVOT VTI is associated with a worse prognosis.

Conclusion

The VTI and minute distance are simple, feasible and reproducible measurements to serially track the SV and CO and thus their high value in the hemodynamic monitoring of critically ill patients in point-of-care settings. In addition, the LVOT VTI is able to predict outcomes in selected populations.

Severity of acute respiratory distress syndrome and echocardiographic findings in clinical practice-an echocardiographic pilot study

BACKGROUNDS

The still high poor outcome of ARDS may be more consequence of circulatory failure than hypoxemia per se. For patients with circulatory failure and ARDS, hemodynamic instability is directly related to ARDS following pulmonary circulation dysfunction and its consequence - right ventricular (RV) dysfunction.

OBJECTIVES

We hypothesize that in the era of protective ventilation, echocardiographic abnormalities did not parallel ARDS severity, defined by the degree of hypoxemia.

METHODS

We included 63 consecutively identified mechanically ventilated ARDS patients (1st January 2015 to 31th December 2016). All had echocardiography performed routinely within the first 12 h after ICU admission.

RESULTS

The analysis included 110 exams. Twenty-eight patients had severe ARDS (28/63, 44.4%), 27 had moderate ARDS (27/63, 42.1%) and 8 mild ARDS (8/63, 12.7%).There was no difference in echocardiographic findings between mild-moderate and severe ARDS. At Pearson's linear regression analysis, TAPSE was directly correlated with LVEF (r = 0.22, p = 0.021) and inversely with sPAP (r = -0.37, p < 0.001). Systolic pulmonary arterial pressure (sPAP) showed a direct correlation with pCO₂ (r = 0.30, p = 0.002) and an inverse one with pH (r = -0.35, p < 0.001) and TAPSE (r =-0.35, p < 0.001).

CONCLUSIONS

Among patients with ARDS, the severity of disease (as indicated by pO2) does not translate into specific cardiac abnormalities, detected by echocardiography. However, RV function (as indicated by TAPSE) is inversely related to pCO₂ and to sPAP (which therefore may be underestimated in presence ofRV dysfunction). Our data strongly suggest that in mechanically ventilated ARDS, the interpretation of echo findings should consider also pCO₂ values.

Low left ventricular outflow tract velocity time integral is associated with poor outcomes in acute pulmonary embolism

The left ventricular outflow tract (LVOT) velocity time integral (VTI) is an easily measured echocardiographic stroke volume index analog. Low values predict adverse outcomes in left ventricular failure. We postulate the left ventricular VTI may be a signal of right ventricular dysfunction in acute pulmonary embolism, and therefore a predictor of poor outcomes. We retrospectively reviewed echocardiograms on all Pulmonary Embolism Response Team activations at our institution at the time of pulmonary embolism diagnosis. Low LVOT VTI was defined as ⩽ 15 cm. We examined two composite outcomes: (1) in-hospital death or cardiac arrest; and (2) shock or need for primary reperfusion therapies. Sixty-one of 188 patients (32%) had a LVOT VTI of ⩽ 15 cm. Low VTI was associated with in-hospital death or cardiac arrest (odds ratio (OR) 6, 95% CI 2, 17.9; p = 0.0014) and shock or need for reperfusion (OR 23.3, 95% CI 6.6, 82.1; p < 0.0001). In a multivariable model, LVOT VTI ⩽ 15 remained significant for death or cardiac arrest (OR 3.48, 95% CI 1.02, 11.9; p = 0.047) and for shock or need for reperfusion (OR 8.12, 95% CI 1.62, 40.66; p = 0.011). Among intermediate-high-risk patients, low VTI was the only variable associated with the composite outcome of death, cardiac arrest, shock, or need for reperfusion (OR 14, 95% CI 1.7, 118.4; p = 0.015). LVOT VTI is associated with adverse short-term outcomes in acute pulmonary embolism. The VTI may help risk stratify patients with intermediate-high-risk pulmonary embolism.

Transthoracic echocardiographic assessment of cardiac output in mechanically ventilated critically ill patients by intensive care unit physicians

Background and objectives

Transthoracic echocardiography may potentially be useful to obtain a prompt, accurate and non-invasive estimation of cardiac output. We evaluated whether non-cardiologist intensivists may obtain accurate and reproducible cardiac output determination in hemodynamically unstable mechanically ventilated patients.

Methods

We studied 25 hemodynamically unstable mechanically ventilated intensive care unit patients with a pulmonary artery catheter in place. Cardiac output was calculated using the pulsed Doppler transthoracic echocardiography technique applied to the left ventricular outflow tract in apical 5 chamber view by two intensive care unit physicians who had received a basic Transthoracic Echocardiography training plus a specific training focused on Doppler, left ventricular outflow tract and velocity-time integral determination.

Results

Cardiac output assessment by transthoracic echocardiography was feasible in 20 out of 25 enrolled patients (80%) and showed an excellent inter-operator reproducibility (Pearson correlation test r = 0.987; Cohen's K = 0.840). Overall, the mean bias was 0.03 L.min⁻¹, with limits of agreement −0.52 and +0.57 L.min⁻¹. The concordance correlation coefficient (ρ_c) was 0.986 (95% IC 0.966–0.995) and 0.995 (95% IC 0.986–0.998) for physician 1 and 2, respectively. The value of accuracy (C_b) of CO_TTE measurement was 0.999 for both observers. The value of precision (ρ) of CO_TTE measurement was 0.986 and 0.995 for observer 1 and 2, respectively.

Conclusions

A specific training focused on Doppler and VTI determination added to the standard basic transthoracic echocardiography training allowed non-cardiologist intensive care unit physicians to achieve a quick, reproducible and accurate snapshot cardiac output assessment in the majority of mechanically ventilated intensive care unit patients.

[Transthoracic echocardiographic assessment of cardiac output in mechanically ventilated critically ill patients by intensive care unit physicians]

BACKGROUND AND OBJECTIVES

Transthoracic echocardiography may potentially be useful to obtain a prompt, accurate and non-invasive estimation of cardiac output. We evaluated whether non-cardiologist intensivists may obtain accurate and reproducible cardiac output determination in hemodynamically unstable mechanically ventilated patients.

METHODS

We studied 25 hemodynamically unstable mechanically ventilated intensive care unit patients with a pulmonary artery catheter in place. Cardiac output was calculated using the pulsed Doppler transthoracic echocardiography technique applied to the left ventricular outflow tract in apical 5 chamber view by two intensive care unit physicians who had received a basic Transthoracic Echocardiography training plus a specific training focused on Doppler, left ventricular outflow tract and velocity-time integral determination.

RESULTS

Cardiac output assessment by transthoracic echocardiography was feasible in 20 out of 25 enrolled patients (80%) and showed an excellent inter-operator reproducibility (Pearson correlation test r=0.987; Cohen's K=0.840). Overall, the mean bias was 0.03L.min^-1, with limits of agreement -0.52 and +0.57L.min^-1. The concordance correlation coefficient (ρ_c) was 0.986 (95% IC 0.966-0.995) and 0.995 (95% IC 0.986-0.998) for physician 1 and 2, respectively. The value of accuracy (C_b) of CO_TTE measurement was 0.999 for both observers. The value of precision (ρ) of CO_TTE measurement was 0.986 and 0.995 for observer 1 and 2, respectively.

CONCLUSIONS

A specific training focused on Doppler and VTI determination added to the standard basic transthoracic echocardiography training allowed non-cardiologist intensive care unit physicians to achieve a quick, reproducible and accurate snapshot cardiac output assessment in the majority of mechanically ventilated intensive care unit patients.

Reference intervals and percentile curve for left ventricular outflow tract (LVOT), velocity time integral (VTI), and LVOT-VTI-derived hemodynamic parameters in healthy children and adolescents: Analysis of echocardiographic methods association and agreement

BACKGROUND

Echocardiographic reference intervals (RIs) for left ventricular outflow tract (LVOT) and velocity time integral (VTI) are scarce in pediatrics.

AIMS

(a) to generate RIs and percentiles for LVOT, VTI, and hemodynamic variables in healthy children and adolescents from Argentina; (b) to analyze the equivalence between stroke volume (SV), cardiac output (CO), and cardiac index (CI) obtained from two-dimensional echocardiography (2D) and LVOT-VTI analysis with pulsed wave Doppler (PWD); and (c) to analyze the association between subjects' characteristics and VTI and LVOT-VTI-derived parameters.

METHODS

Two-dimensional and PWD studies were done in 385 subjects (5-24 years). Mean and standard deviation age-related and body surface area (BSA)-related equations were obtained for VTI and LVOT-VTI-derived parameters (parametric regression methods based on fractional polynomials). BSA- and age-specific percentiles were determined.

RESULTS

Pulsed wave Doppler- and 2D-derived parameters were positively correlated. However, PWD values were always lower than those from 2D. Specific RIs for PWD and 2D data were necessary. Covariance analysis showed that sex-specific RIs were required for LVOT, but not for VTI, VTI-derived CO and CI. Age-related RIs were obtained for LVOT, LVOT-VTI, and VTI-derived CO and CI. BSA-related RIs for VTI-derived CO and CI were obtained.

CONCLUSIONS

Stroke volume, CO, and CI data from 2D and PWD are not equivalent. An accurate analysis of LVOT-VTI-derived parameters requires considering age and BSA. In this study, age- and BSA-related RIs and percentiles for LVOT, VTI, and hemodynamic parameters in healthy children and adolescents were determined, discriminating data according to the methodological approach (2D or PWD).

Basic and advanced echocardiographic evaluation of myocardial dysfunction in sepsis and septic shock

Sepsis continues to be a leading cause of mortality and morbidity in the intensive care unit. Cardiovascular dysfunction in sepsis is associated with worse short- and long-term outcomes. Sepsis-related myocardial dysfunction is noted in 20%-65% of these patients and manifests as isolated or combined left or right ventricular systolic or diastolic dysfunction. Echocardiography is the most commonly used modality for the diagnosis of sepsis-related myocardial dysfunction. With the increasing use of ultrasonography in the intensive care unit, there is a renewed interest in sepsis-related myocardial dysfunction. This review summarises the current scope of literature focused on sepsis-related myocardial dysfunction and highlights the use of basic and advanced echocardiographic techniques for the diagnosis of sepsis-related myocardial dysfunction and the management of sepsis and septic shock.

Assessment of left ventricular ejection fraction in critically ill patients at the time of speckle tracking echocardiography: intensivists in training for echocardiography versus experienced operators

BACKGROUND

The biplane Simpson's method is considered the gold standard to assess and monitor left ventricular (LV) ejection fraction (EF) in critically ill patients. Recently, a new semi-automatic technique based on speckle tracking echocardiography called "Auto-EF" has been introduced. We compared LVEF values obtained with biplane Simpson's method and Auto-EF by two groups of operators: trainee echocardiography intensivists and experienced echocardiographers.

METHODS

A standard transthoracic echocardiography was performed on 37 patients. According to image quality 29 patients were selected. Each inexperienced and experienced operator executed an off-line analysis using both Simpson's method and Auto-EF. LVEF obtained by the two groups of operators were then compared.

RESULTS

EF values assessed with Simpson's method showed a moderate correlation (r=0.70, P<0.01) between inexperienced and experienced operators. The Bland-Altman analysis showed a mean bias of 0.3% with limits of agreement (LoA) from -24.4 to +25.1%. Values obtained with Auto-EF showed a good correlation (r=0.94, P<0.01) with a mean bias of 0.2% and LoA from -10.1 to +10.4%.

CONCLUSIONS

Due to its semiautomatic nature, for inexpert operators Auto-EF seems more reproducible than the traditional Simpson's method for monitoring left ventricular function in critically ill patients.

Lung and cardiac ultrasound for hemodynamic monitoring of patients with severe pre-eclampsia

OBJECTIVE

To evaluate lung and cardiac ultrasound for the assessment of fluid tolerance and fluid responsiveness before and after delivery in pregnant women with severe pre-eclampsia (PE).

METHODS

This was a prospective observational study of singleton pregnant women with severe PE and healthy term controls. Lung ultrasound echo comet score (ECS), which denotes the amount of extravascular lung water, was obtained using the 28-rib interspaces technique. The echocardiographic E/e' ratio, measured by pulsed-wave and tissue Doppler, was used as a marker of diastolic left ventricular function. Fluid responsiveness was assessed by measuring changes in stroke volume (SV) with passive leg raising (PLR). SV was calculated from the left ventricular flow velocity-time integral measured by pulsed-wave Doppler at baseline and after PLR. Change in SV ≥ 12% was considered to indicate fluid responsiveness. Measurements obtained 1 day before delivery and 1 and 4 days after delivery were compared in the two groups (PE vs controls).

RESULTS

We included 21 women with severe PE and 12 healthy controls. ECS and E/e' ratio were higher in women with PE than in controls, both before delivery (P = 0.002 and P = 0.02) and 1 day postdelivery (P = 0.02 and P = 0.03); however there was no difference at 4 days postdelivery (P = 0.63 and P = 0.90). The change in SV with PLR before (P = 0.26) and after (P = 0.71) delivery did not differ between groups. An increase in SV ≥ 12% was observed in three (14%) women with PE and four (33%) controls before delivery and in four (19%) women with PE and two (17%) controls 1 day after delivery.

CONCLUSIONS

Severe PE is associated with an increase in extravascular lung water, which could in part be caused by disturbed diastolic left ventricular function. Excess lung water can be identified by lung ultrasound assessment in women with severe PE before the appearance of clinical signs. Only a small proportion of these women are fluid responsive. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Adrenomedullin and endothelin-1 are associated with myocardial injury and death in septic shock patients

Background

Adrenomedullin and endothelin-1 are hormones with opposing effects on the cardiovascular system. Adrenomedullin acts as a vasodilator and seems to be important for the initiation and continuation of the hyperdynamic circulatory response in sepsis. Endothelin-1 is a vasoconstrictor and has been linked to decreased cardiac performance. Few studies have studied the relationship between adrenomedullin and endothelin-1, and morbidity and mortality in septic shock patients. High-sensitivity troponin T (hsTNT) is normally used to diagnose acute cardiac injury but is also prognostic for outcome in intensive care. We investigated the relationship between mid-regional pro-adrenomedullin (MR-proADM), C-terminal pro-endothelin-1 (CT-proET-1), and myocardial injury, measured using transthoracic echocardiography and hsTNT in septic shock patients. We were also interested in the development of different biomarkers throughout the ICU stay, and how early measurements were related to mortality. Further, we assessed if a positive biomarker panel, consisting of MR-proADM, CT-proET-1, and hsTNT changed the odds for mortality.

Methods

A cohort of 53 consecutive patients with septic shock had their levels of MR-proADM, CT-proET-1, hsTNT, and left ventricular systolic functions prospectively measured over 7 days. The relationship between day 1 levels of MR-proADM/CT-proET-1 and myocardial injury was studied. We also investigated the relationship between biomarkers and early (7-day) and later (28-day) mortality. Likelihood ratios, and pretest and posttest odds for mortality were calculated.

Results

Levels of MR-proADM and CT-proET-1 were significantly higher among patients with myocardial injury and were correlated with left ventricular systolic dysfunction. MR-proADM and hsTNT were significantly higher among 7-day and 28-day non-survivors. CT-proET-1 was also significantly higher among 28-day but not 7-day non-survivors. A positive biomarker panel consisting of the three biomarkers increased the odds for mortality 13-fold to 20-fold.

Conclusions

MR-proADM and CT-proET-1 are associated with myocardial injury. A biomarker panel combining MR-proADM, CT-proET-1, and hsTNT increases the odds ratio for death, and may improve currently available scoring systems in critical care.

Influence of Diaphragmatic Motion on Inferior Vena Cava Diameter Respiratory Variations in Healthy Volunteers

BACKGROUND

The collapsibility index of inferior vena cava (cIVC) is widely used to decide fluid infusion in spontaneously breathing intensive care unit patients. The authors hypothesized that high inspiratory efforts may induce false-positive high cIVC values. This study aims at determining a value of diaphragmatic motion recorded by echography that could predict a high cIVC (more than or equal to 40%) in healthy volunteers.

METHODS

The cIVC and diaphragmatic motions were recorded for three levels of inspiratory efforts. Right and left diaphragmatic motions were defined as the maximal diaphragmatic excursions. Receiver operating characteristic curves evaluated the performance of right diaphragmatic motion to predict a cIVC more than or equal to 40% defining the best cutoff value.

RESULTS

Among 52 included volunteers, interobserver reproducibility showed a generalized concordance correlation coefficient (ρc) above 0.9 for all echographic parameters. Right diaphragmatic motion correlated with cIVC (r = 0.64, P < 0.0001). Univariate analyses did not show association between cIVC and age, sex, weight, height, or body mass index. The area under the receiver operating characteristic curves for cIVC more than or equal to 40% was 0.87 (95% CI, 0.81 to 0.93). The best diaphragmatic motion cutoff was 28 mm (Youden Index, 0.65) with sensitivity of 89% and specificity of 77%. The gray zone area was 25 to 43 mm.

CONCLUSIONS

Inferior vena cava collapsibility is affected by diaphragmatic motion. During low inspiratory effort, diaphragmatic motion was less than 25 mm and predicted a cIVC less than 40%. During maximal inspiratory effort, diaphragmatic motion was more than 43 mm and predicted a cIVC more than 40%. When diaphragmatic motion ranged from 25 to 43 mm, no conclusion on cIVC value could be done.

Incidence and outcome of cardiac injury in patients with severe head trauma

BACKGROUND

Although cardiac injury has been reported in patients with various neurological conditions, few data report cardiac injury in patients with traumatic brain injury (TBI). The aim of this work is to report the incidence of cardiac injury in patients with TBI and its impact on patient outcome.

METHODS

A prospective observational study was conducted on a cohort of 50 patients with severe TBI. Only patients with isolated severe TBI defined as Glascow coma scale (GCS) < 8 were included in the study. Acute physiology and chronic health evaluation (APACHE) II score, GCS, hemodynamic data, serum Troponin I, electrocardiogram (ECG), and echocardiographic examination, and patients' outcome were recorded. A neurogenic cardiac injury score (NCIS) was calculated for all patients (rising troponin = 1, abnormal echocardiography = 1, hypotension = 1). Univariate and multivariate analyses for risk factors for mortality were done for all risk factors. RESULTS AND DISCUSSION: Fifty patients were included; age was 31 ± 12, APACHE II was 21 ± 5, and male patients were 45 (90 %). Troponin I was elevated in 27 (54 %) patients, abnormal echocardiography and hypotension were documented in 14 (28 %) and 16 (32 %) patients, respectively. The in-hospital mortality was 36 %. Risk factors for mortality by univariate analysis were age, GCS, APACHE II score, serum troponin level, NCIS, and hypotension. However, in multivariate analysis, the only two independent risk factors for mortality were APACHE II score (OR = 1.25, 95 % confidence interval: 1.02-1.54, P = 0.03) and NCIS score (OR = 8.38, 95 % confidence interval: 1.44-48.74, P = 0.018).

CONCLUSIONS

Cardiac injury is common in patients with TBI and is associated with increased mortality. The association of high NCIS and poor outcome in these patients warrants a further larger study.

Serial measurements of troponin and echocardiography in patients with moderate-to-severe acute respiratory distress syndrome

PURPOSE

To assess the clinical significance of serial troponin I levels (measured in the first 72 hours from admission) in 42 consecutive patients with moderate-to-severe acute respiratory distress syndrome (ARDS). Echocardiography and electrocardiogram testings were serially performed in the time window.

MATERIALS AND METHODS

Troponin I was measured every 12 hours in the first 72 hours from intensive care unit (ICU) admission. Echocardiography and electrocardiogram testings were serially performed in the same time window to clinically interpret Tn I levels.

RESULTS

Patients with admission positive Tn I (38.1%) showed higher values of systolic pulmonary hypertension (P = .013) associated with significantly lower values of tricuspid annular plane excursion (P = .011). Twenty-five patients (25/42, 59.5%) exhibited positive peak Tn I and at second echocardiographic assessment exhibited significant lower tricuspid annular plane excursion values (P = .005). At stepwise regression analysis the following variables were an independent predictor for in-ICU mortality: Pco2 (OR 1.08, 95% CI 1.011-1.161, P = .023), systolic pulmonary arterial hypertension (OR 0.83, 95% CI 0.701-0.977, P = .002), log peak Tn I (OR 3.56, 95% CI 1.045-12.132, P = .042).

CONCLUSIONS

In moderate-to-severe ARDS, serial troponin I assessment together with echocardiography evaluation helped to identify a subgroup at higher risk for in-ICU death. Moreover, troponin release can be related to right ventricular dysfunction, thus highlighting the clinical role of echocardiography in ARDS patients.

Hyperdynamic left ventricular ejection fraction in the intensive care unit

Introduction

Limited information exists on the etiology, prevalence, and significance of hyperdynamic left ventricular ejection fraction (HDLVEF) in the intensive care unit (ICU). Our aim in the present study was to compare characteristics and outcomes of patients with HDLVEF with those of patients with normal left ventricular ejection fraction in the ICU using a large, public, deidentified critical care database.

Methods

We conducted a longitudinal, single-center, retrospective cohort study of adult patients who underwent echocardiography during a medical or surgical ICU admission at the Beth Israel Deaconess Medical Center using the Multiparameter Intelligent Monitoring in Intensive Care II database. The final cohort had 2867 patients, of whom 324 had HDLVEF, defined as an ejection fraction >70 %. Patients with an ejection fraction <55 % were excluded.

Results

Compared with critically ill patients with normal left ventricular ejection fraction, the finding of HDLVEF in critically ill patients was associated with female sex, increased age, and the diagnoses of hypertension and cancer. Patients with HDLVEF had increased 28-day mortality compared with those with normal ejection fraction in multivariate logistic regression analysis adjusted for age, sex, Sequential Organ Failure Assessment score, Elixhauser score for comorbidities, vasopressor use, and mechanical ventilation use (odds ratio 1.38, 95 % confidence interval 1.039–1.842, p =0.02).

Conclusions

The presence of HDLVEF portended increased 28-day mortality, and may be helpful as a gravity marker for prognosis in patients admitted to the ICU. Further research is warranted to gain a better understanding of how these patients respond to common interventions in the ICU and to determine if pharmacologic modulation of HDLVEF improves outcomes.

Variability in echocardiographic measurements of left ventricular function in septic shock patients

Background

Echocardiography is increasingly used for haemodynamic evaluation and titration of therapy in intensive care, warranting reliable and reproducible measurements. The aim of this study was to evaluate the observer dependence of echocardiographic findings of left ventricular (LV) diastolic and systolic dysfunction in patients with septic shock.

Methods

Echocardiograms performed in 47 adult patients admitted with septic shock to a general intensive care unit (ICU) were independently evaluated by one cardiologist and one intensivist for the following signs: decreased diastolic tissue velocity of the base of the LV septum (é), increased early mitral inflow (E) to é ratio (E/é), decreased LV ejection fraction (EF) and decreased LV global longitudinal peak strain (GLPS). Diastolic dysfunction was defined as é <8.0 cm/s and/or E/é ≥15 and systolic dysfunction as EF <50% and/or GLPS > −15%. Ten randomly selected examinations were re-analysed two months later. Pearson’s r was used to test the correlation and Bland-Altman plots to assess the agreement between observers. Kappa statistics were used to test the consistency between readers and intraclass correlation coefficients (ICC) for inter- and intraobserver variability.

Results

In 44 patients (94%), image quality was sufficient for echocardiographic measurements. The agreement between observers was moderate (k = 0.60 for é, k = 0.50 for E/é and k = 0.60 for EF) to good (k = 0.71 for GLPS). Pearson’s r was 0.76 for é, 0.85 for E/é, 0.78 for EF and 0.84 for GLPS (p < 0.001 for all four). The ICC between observers for é was very good (0.85; 95% confidence interval (CI) 0.73-0.92), good for E/é (0.70; 95% CI 0.45 – 0.84), very good for EF (0.87; 95% CI 0.77 – 0.93), excellent for GLPS (0.91; 95% CI 0.74 – 0.95), and very good for all measures repeated by one of the observers. On Bland-Altman analysis, the mean differences and 95% limits of agreement for é, E/é, EF and GLPS were −0.01 (0.04 – 0.07), 2.0 (−14.2 – 18.1), 0.86 (−16 – 14.3) and 0.04 (−5.04 – 5.12), respectively.

Conclusions

Moderate observer-related differences in assessing LV dysfunction were seen. GLPS is the least user dependent and most reproducible echocardiographic measurement of LV function in septic shock.

Electronic supplementary material

The online version of this article (doi:10.1186/s12947-015-0015-6) contains supplementary material, which is available to authorized users.

Strain echocardiography in septic shock - a comparison with systolic and diastolic function parameters, cardiac biomarkers and outcome

Introduction

Myocardial dysfunction is a well-known complication in septic shock but its characteristics and frequency remains elusive. Here, we evaluate global longitudinal peak strain (GLPS) of the left ventricle as a diagnostic and prognostic tool in septic shock.

Methods

Fifty adult patients with septic shock admitted to a general intensive care unit were included. Transthoracic echocardiography was performed on the first day, and repeated during and after ICU stay. Laboratory and clinical data and data on outcome were collected daily from admission and up to 7 days, shorter in cases of death or ICU discharge. The correlation of GLPS to left ventricular systolic and diastolic function parameters, cardiac biomarkers and clinical data were compared using Spearman’s correlation test and linear regression analysis, and the ability of GLPS to predict outcome was evaluated using a logistic regression model.

Results

On the day of admission, there was a strong correlation and co-linearity of GLPS to left ventricular ejection fraction (LVEF), mitral annular motion velocity (é) and to amino-terminal pro-brain natriuretic peptide (NT-proBNP) (Spearman’s ρ -0.70, −0.53 and 0.54, and R² 0.49, 0.20 and 0.24, respectively). In LVEF and NT-proBNP there was a significant improvement during the study period (analysis of variance (ANOVA) with repeated measures, p = 0.05 and p < 0.001, respectively), but not in GLPS, which remained unchanged over time (p = 0.10). GLPS did not correlate to the improvement in clinical characteristics over time, did not differ significantly between survivors and non-survivors (−17.4 (−20.5-(−13.7)) vs. -14.7 (−19.0 - (−10.6)), p = 0.11), and could not predict mortality.

Conclusions

GLPS is frequently reduced in septic shock patients, alone or in combination with reduced LVEF and/or é. It correlates with LVEF, é and NT-proBNP, and remains affected over time. GLPS may provide further understanding on the character of myocardial dysfunction in septic shock.

Limited echocardiography-guided therapy in subacute shock is associated with change in management and improved outcomes

PURPOSE

The purpose of the study was to compare the effect of limited echocardiography (LE)-guided therapy to standard management on 28-day mortality, intravenous fluid prescription, and inotropic dosing following early resuscitation for shock.

MATERIALS AND METHODS

Two hundred twenty critically ill patients with undifferentiated shock from a quaternary intensive care unit were included in the study. The LE group consisted of 110 consecutive patients prospectively studied over a 12-month period receiving LE-guided management. The standard management group consisted of 110 consecutive patients retrospectively studied with shock immediately prior to the LE intervention.

RESULTS

In the LE group, fluid restriction was recommended in 71 (65%) patients and initiation of dobutamine in 27 (25%). Fluid prescription during the first 24 hours was significantly lower in LE patients (49 [33-74] vs 66 [42-100] mL/kg, P = .01), whereas 55% more LE patients received dobutamine (22% vs 12%, P = .01). The LE patients had improved 28-day survival (66% vs 56%, P = .04), a reduction in stage 3 acute kidney injury (20% vs 39%), and more days alive and free of renal support (28 [9.7-28] vs 25 [5-28], P = .04).

CONCLUSIONS

Limited echocardiography-guided management following early resuscitation is associated with improved survival, less fluid, and increased inotropic prescription. A prospective randomized control trial is required to verify these results.

Lung Ultrasound Predicts Interstitial Syndrome and Hemodynamic Profile in Parturients with Severe Preeclampsia

Background:

The role of lung ultrasound has never been evaluated in parturients with severe preeclampsia. The authors’ first aim was to assess the ability of lung ultrasound to detect pulmonary edema in severe preeclampsia. The second aim was to highlight the relation between B-lines and increased left ventricular end-diastolic pressures.

Methods:

This prospective cohort study was conducted in a level-3 maternity during a 12-month period. Twenty parturients with severe preeclampsia were consecutively enrolled. Both lung and cardiac ultrasound examinations were performed before (n = 20) and after delivery (n = 20). Each parturient with severe preeclampsia was compared with a control healthy parturient. Pulmonary edema was determined using two scores: the B-pattern and the Echo Comet Score. Left ventricular end-diastolic pressures were assessed by transthoracic echocardiography.

Results:

Lung ultrasound detected interstitial edema in five parturients (25%) with severe preeclampsia. A B-pattern was associated to increased mitral valve early diastolic peak E (116 vs. 90 cm/s; P = 0.05) and to increased E/E’ ratio (9.9 vs. 6.6; P &lt; 0.001). An Echo Comet Score of greater than 25 predicted an increase in filling pressures (E/E’ ratio &gt;9.5) with a sensitivity and specificity of 1.00 (95% CI, 0.69 to 1.00) and 0.82 (95% CI, 0.66 to 0.92), respectively.

Conclusions:

In parturients with severe preeclampsia, lung ultrasound detects both pulmonary edema and increased left ventricular end-diastolic pressures. The finding of a B-pattern should restrict the use of fluid. However, these preliminary results are associations from a single sample. They need to be replicated in a larger, definitive study.

Preoperative fasting does not affect haemodynamic status: a prospective, non-inferiority, echocardiography study

BACKGROUND

The link between preoperative fasting and hypovolaemia remains unclear. We tested the hypothesis that preoperative fasting does not significantly increase the proportion of patients with hypovolaemia according to transthoracic echocardiography (TTE) criteria.

METHODS

Patients of ASA status I-III and without bowel preparation were included in a non-inferiority, prospective, single-centre trial. Patients underwent passive leg raising (PLR) test and TTE at admission (Day 0) and after 8 h fasting (Day 1). The primary hypothesis was that an 8 h preoperative fasting does not increase the proportion (margin=5%) of patients with a positive PLR test ('functional approach'). The secondary hypothesis was that echocardiographic filling pressures or stroke volume (margin 10%) are not affected by preoperative fasting ('static approach').

RESULTS

One hundred patients were included and 98 analysed. After an 8 h fasting, the change in the proportion of responders to PLR was -6.1% [95% confidence interval (CI)=-16.0 to 3.8] of responders to PLR test on Day 0 when compared with Day 1. Because 95% CI was strictly inferior to 5%, there was no significant increase in the proportion of PLR responders on Day 1 when compared with Day 0. The 95% CI changes of static variables were always fewer than 10%, meaning that preoperative fasting induced significantly no relevant changes in static variables.

CONCLUSION

Preoperative fasting did not alter TTE dynamic and static preload indices in ASA I-III adult patients. These results suggest that preoperative fasting does not induce significant hypovolaemia. Clinical trial registration NCT 01258361.