Hemodynamic assessment of critically ill patients using echocardiography Doppler

Resuscitative Transesophageal Echocardiography in Critical Care

The use of focused critical care echocardiography, diagnostic modality aimed to provide immediate and actionable information, represents a core competency of contemporary intensive care medicine. Resuscitative transesophageal echocardiography (TEE) is a focused, goal-directed examination performed at the point of care, for the rapid evaluation of critically ill patients in whom transthoracic images are either logistically untenable, inadequate, or unobtainable. Some of the applications of TEE in the management of critically ill patients include the evaluation of patients in shock and cardiac arrest, the assessment of trauma patients, and the guidance of several endovascular procedures. Due to the indwelling nature of the transducer, TEE can provide consistently high-quality images and allows for continuous monitoring during hemodynamic interventions, making it ideally suited for the evaluation of critically ill patients. In this article, we review the evolving landscape of resuscitative TEE, discuss the rationale, supporting evidence, safety, and training for the use of this modality in critical care settings. We address the transdisciplinary evolution of TEE and the practical aspects of its implementation in emergency and critical care settings.

Point-of-care ultrasonography to predict fluid responsiveness in children: A systematic review and meta-analysis

BACKGROUND

Point-of-care ultrasonography (POCUS) is proposed as a valuable method for hemodynamic monitoring and several ultrasound-based predictors of fluid responsiveness have been studied. The main objective of this study was to assess the accuracy of these predictors in children.

METHODS

PubMed, Embase, Scopus, ClinicalTrials.gov, and Cochrane Library databases were searched for relevant publications through July 2022. Pediatric studies reporting accuracy estimates of ultrasonographic predictors of fluid responsiveness were included since they had used a standard definition of fluid responsiveness and had performed an adequate fluid challenge.

RESULTS

Twenty-three studies involving 1028 fluid boluses were included, and 12 predictors were identified. A positive response to fluid infusion was observed in 59.7% of cases. The vast majority of participants were mechanically ventilated (93.4%). The respiratory variation in aortic blood flow peak velocity (∆Vpeak) was the most studied predictor, followed by the respiratory variation in inferior vena cava diameter (∆IVC). The pooled sensitivity and specificity of ∆Vpeak were 0.84 (95% CI, 0.76-0.90) and 0.82 (95% CI, 0.75-0.87), respectively, and the area under the summary receiver operating characteristic curve (AUSROC) was 0.89 (95% CI, 0.86-0.92). The ∆IVC presented a pooled sensitivity and specificity of 0.79 (95% CI, 0.62-0.90) and 0.70 (95% CI, 0.51-0.84), respectively, and an AUSROC of 0.81 (95% CI, 0.78-0.85). Significant heterogeneity in accuracy estimates across studies was observed.

CONCLUSIONS

POCUS has the potential to accurately predict fluid responsiveness in children. However, only ∆Vpeak was found to be a reliable predictor. There is a lack of evidence supporting the use of POCUS to guide fluid therapy in spontaneously breathing children.

Carotid doppler ultrasonography as a method to predict fluid responsiveness in mechanically ventilated children

AIMS

The aim of this study was to investigate whether respiratory variations in carotid and aortic blood flows measured by Doppler ultrasonography could accurately predict fluid responsiveness in critically ill children.

METHODS

This was a prospective single-center study including mechanically ventilated children who underwent fluid replacement at the discretion of the attending physician. Response to fluid load was defined by a stroke volume increase of more than 15%. Maximum and minimum values of velocity peaks were determined over one controlled respiratory cycle before and after volume expansion. Respiratory changes in velocity peak of the carotid (∆Vpeak_Ca) and aortic (∆Vpeak_Ao) blood flows were calculated as the difference between the maximum and minimum values divided by the mean of the two values and were expressed as a percentage.

RESULTS

A total of 30 patients were included, of which twelve (40%) were fluid responders and 18 (60%) non-responders. Before volume expansion, both ∆Vpeak_Ca and ∆Vpeak_Ao were higher in responders than in non-responders (17.1% vs 4.4%; p < .001 and 22.8% vs 6.4%; p < .001, respectively). ∆Vpeak_Ca could effectively predict fluid responsiveness (AUC 1.00, 95% CI 0.88-1.00), as well as ∆Vpeak_Ao (AUC 0.94, 95% CI 0.80-0.99). The best cutoff values were 10.6% for ∆Vpeak_Ca (sensitivity, specificity, positive predictive value and negative predictive value of 100%) and 18.2% for ∆Vpeak_Ao (sensitivity, 91.7%; specificity, 88.9%; positive predictive value, 84.6%; negative predictive value, 94.1%). Volume expansion-induced changes in stroke volume correlated with the ∆Vpeak_Ca and ∆Vpeak_Ao before volume expansion (ρ of 0.70 and 0.61, respectively; p < .001 for both).

CONCLUSIONS

Analysis of respiratory changes in carotid and aortic blood flows are accurate methods for predicting fluid responsiveness in children under invasive mechanical ventilation.

Echocardiography in the intensive care unit: An essential tool for diagnosis, monitoring and guiding clinical decision-making

In the last years, new trends on patient diagnosis for admission in cardiac intensive care unit (CICU) have been observed, shifting from acute myocardial infarction or acute heart failure to non-cardiac diseases such as sepsis, acute respiratory failure or acute kidney injury. Moreover, thanks to the advances in scientific knowledge and higher availability, there has been increasing use of positive pressure mechanical ventilation which has its implications on the heart. Therefore, there is a growing need for Cardiac intensivists to quickly, noninvasively and repeatedly evaluate various hemodynamic conditions and the response to therapy. Transthoracic critical care echocardiography (CCE) currently represents an essential tool in CICU, as it is used to evaluate biventricular function and complications following acute coronary syndromes, identify the mechanisms of circulatory failure, acute valvular pathologies, tailoring and titrating intravenous treatment or mechanical circulatory support. This could be completed with trans-esophageal echocardiography (TOE), advanced echocardiography and lung ultrasound to provide a thorough evaluation and monitoring of CICU patients. However, CCE could sometimes be challenging as the acquisition of good-quality images is limited by mechanical ventilation, suboptimal patient position or recent surgery with drains on the chest. Moreover, there are some technical caveats that one should bear in mind while performing CCE in order to optimize its use and avoid misleading findings. The aim of this review is to highlight the key role of CCE, providing an updated overview of its main applications and possible pitfalls in order to facilitate its use in CICU for clinical decision-making.

Understanding preload and preload reserve within the conceptual framework of a limited range of possible left ventricular end-diastolic volumes

Preload has been variously defined, but if there is to be a direct relationship with activity of the Frank-Starling mechanism in its action to increase the force and extent of contraction, preload must directly reflect myocardial stretch. The Frank-Starling mechanism is activated during any stretch of a cardiac chamber beyond its resting size, which is present immediately before contraction. Every left ventricle has an intrinsic and limited range of possible volumes at end diastole. There is a curvilinear relationship between left ventricular (LV) end-diastolic pressure (LVEDP) and LV end-diastolic volume (LVEDV), and, at maximal or near maximal LVEDV, there will be a high LVEDP. Within the possible range, the LVEDV will be determined by the extent of filling, any change in LVEDV will result in changed activity of the Frank-Starling mechanism, and change in LVEDV might, therefore, be considered to represent change in preload. On the other hand, it is the difference between the current and the maximal possible LVEDV (or the preload reserve) that may be of the most clinical relevance. There is a reciprocal relationship between preload and preload reserve, with minor or absent LV preload reserve indicating that there will be either minimal or no increase in stroke volume following intravenous fluid administration. As left atrial pressure can remain within the normal range when the LVEDP is elevated, it is LVEDP, and not left atrial pressure, that provides the most reliable guide to preload reserve in an individual at a specific period in time.

Continuous cardiac output assessment or serial echocardiography during septic shock resuscitation?

Septic shock is the leading cause of cardiovascular failure in the intensive care unit (ICU). Cardiac output is a primary component of global oxygen delivery to organs and a sensitive parameter of cardiovascular failure. Any mismatch between oxygen delivery and rapidly varying metabolic demand may result in tissue dysoxia, hence organ dysfunction. Since the intricate alterations of both vascular and cardiac function may rapidly and widely change over time, cardiac output should be measured repeatedly to characterize the type of shock, select the appropriate therapeutic intervention, and evaluate patient's response to therapy. Among the numerous techniques commercially available for measuring cardiac output, transpulmonary thermodilution (TPT) provides a continuous monitoring with external calibration capability, whereas critical care echocardiography (CCE) offers serial hemodynamic assessments. CCE allows early identification of potential sources of inaccuracy of TPT, including right ventricular failure, severe tricuspid or left-sided regurgitations, intracardiac shunt, very low flow states, or dynamic left ventricular outflow tract obstruction. In addition, CCE has the unique advantage of depicting the distinct components generating left ventricular stroke volume (large cavity size vs. preserved contractility), providing information on left ventricular diastolic properties and filling pressures, and assessing pulmonary artery pressure. Since inotropes may have deleterious effects if misused, their initiation should be based on the documentation of a cardiac dysfunction at the origin of the low flow state by CCE. Experts widely advocate using CCE as a first-line modality to initially evaluate the hemodynamic profile associated with shock, as opposed to more invasive techniques. Repeated assessments of both the efficacy (amplitude of the positive response) and tolerance (absence of side-effect) of therapeutic interventions are required to best guide patient management. Overall, TPT allowing continuous tracking of cardiac output variations and CCE appear complementary rather than mutually exclusive in patients with septic shock who require advanced hemodynamic monitoring.

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

BACKGROUND

In patients with hemodynamic instability echocardiography has been recommended as the preferred modality to evaluate the underlying pathophysiology. However, due to the fact that recent scientific data on the utilization of echocardiography in German Intensive Care Units (ICU) are scarce, we sought to investigate current practice.

METHODS

A structured, web-based, anonymized survey was performed from May until July 2015 among members of the German Interdisciplinary Association of Critical Care and Emergency Medicine (DIVI) consisting of 14 questions. Descriptive data analysis was performed.

RESULTS

One hundred four intensivists participated in the survey. Two-thirds of participants (66%) used echocardiography regularly for hemodynamic monitoring and stated that it changed the therapy in 26-50% of the cases irrespective of the time performed after ordering the examination. Transthoracic (TTE) were more frequently used than transesophageal (TEE) examinations. Twenty-six percent of the participants held an echocardiography certificate with a formal examination, 27% completed a structured training without an examination and almost half of the questioned ICU personnel (47%) did not complete a comprehensive training.

CONCLUSIONS

The results of this survey demonstrate a widespread utilization of echocardiography as part of routine diagnostic on frequent number of operative ICUs. However, there might be a lack of structured echocardiographic training especially for anesthesiologists.

Critical care ultrasonography in circulatory shock

PURPOSE OF REVIEW

The objective was to define the role of ultrasound in the diagnosis and the management of circulatory shock by critical appraisal of the literature.

RECENT FINDINGS

Assessment of any patient's hemodynamic profile based on clinical examination can be sufficient in several cases, but many times unclarities remain. Arterial catheters and central venous lines are commonly used in critically ill patients for practical reasons, and offer an opportunity for advanced hemodynamic monitoring. Critical care ultrasonography may add to the understanding of the hemodynamic profile at hand. Improvements in ultrasound techniques, for example, smaller devices and improved image quality, may reduce limitations and increase its value as a complementary tool. Critical care ultrasonography has great potential to guide decisions in the management of shock, but operators should be aware of limitations and pitfalls as well. Current evidence comes from cohort studies with heterogeneous design and outcomes.

SUMMARY

Use of ultrasonography for hemodynamic monitoring in critical care expands, probably because of absence of procedure-related adverse events. Easy applicability and the capacity of distinguishing different types of shock add to its increasing role, further supported by consensus statements promoting ultrasound as the preferred tool for diagnostics in circulatory shock.

Expert consensus document: Echocardiography and lung ultrasonography for the assessment and management of acute heart failure

Echocardiography is increasingly recommended for the diagnosis and assessment of patients with severe cardiac disease, including acute heart failure. Although previously considered to be within the realm of cardiologists, the development of ultrasonography technology has led to the adoption of echocardiography by acute care clinicians across a range of specialties. Data from echocardiography and lung ultrasonography can be used to improve diagnostic accuracy, guide and monitor the response to interventions, and communicate important prognostic information in patients with acute heart failure. However, without the appropriate skills and a good understanding of ultrasonography, its wider application to the most acutely unwell patients can have substantial pitfalls. This Consensus Statement, prepared by the Acute Heart Failure Study Group of the ESC Acute Cardiovascular Care Association, reviews the existing and potential roles of echocardiography and lung ultrasonography in the assessment and management of patients with acute heart failure, highlighting the differences from established practice where relevant.

Stress cardiomyopathy of the critically ill: Spectrum of secondary, global, probable and subclinical forms

Stress cardiomyopathy (SC) typically presents as potential acute coronary syndrome (ACS) in previously healthy people. While there may be physical or mental stressors, the initial symptom is usually chest pain. This form conforms to the published Mayo diagnostic criteria, is well reported and as the presentation is initially cardiac, is considered primary SC. Increasingly we see SC develop several days into the hospitalization secondary to medical or surgical critical illness. This condition is more complex, presents atypically, is not easy to recognize and carries a much worse prognosis. Label of Secondary SC is appropriate as it manifests in sicker hospitalized patients with numerous comorbidities. We review the limited but provocative literature pertinent to SC in the critically ill and describe important clues to identify global, subclinical and probable forms of SC. We illustrate the several unique clinical features, demographic differences and propose a diagnostic algorithm to optimize cardiac care in the critically ill.

Hemodynamic Transesophageal Echocardiography-Guided Venous-Arterial Extracorporeal Membrane Oxygenation Support in a Case of Giant Cell Myocarditis

Giant cell myocarditis (GCM) is a rare and commonly fatal form of fulminant myocarditis. During the acute phase, while immunosuppressive therapy is initiated, venoarterial extracorporeal membrane oxygenation (VA-ECMO) support is commonly used as a bridge to heart transplantation or recovery. Until recently, conventional transesophageal echocardiography and transthoracic echocardiography were the tools available for hemodynamic assessment of patients on this form of mechanical circulatory support. Nevertheless, both techniques have their limitations. We present a case of a 54-year-old man diagnosed with GCM requiring VA-ECMO support that was monitored under a novel miniaturized transesophageal echocardiography (hTEE) probe recently approved for 72 hours of continuous hemodynamic monitoring. Our case highlights the value of this novel, flexible, and disposable device for hemodynamic monitoring, accurate therapy guidance, and potential VA-ECMO weaning process of patients with this form of severe myocarditis.

The Diagnostic and Therapeutic Impact of Point-of-Care Ultrasonography in the Intensive Care Unit

PURPOSE

In light of point-of-care ultrasonography's (POCUS) recent rise in popularity, assessment of its impact on diagnosis and treatment in the intensive care unit (ICU) is of key importance.

METHODS

Ultrasound examinations were collected through an ultrasound reporting software in 6 multidisciplinary ICU units from 3 university hospitals in Canada and the United States. This database included a self-reporting questionnaire to assess the impact of the ultrasound findings on diagnosis and treatment. We retrieved the results of these questionnaires and analyzed them in relation to which organs were assessed during the ultrasound examination.

RESULTS

One thousand two hundred and fifteen ultrasound studies were performed on 968 patients. Intensivists considered the image quality of cardiac ultrasound to be adequate in 94.7% compared to 99.7% for general ultrasound ( P < .001). The median duration of a cardiac examination was 10 (interquartile range [IQR] 10) minutes compared to 5 (IQR 8) minutes for a general examination ( P < .001). Overall, ultrasound findings led to a change in diagnosis in 302 studies (24.9%) and to a change in management in 534 studies (44.0%). A change in diagnosis or management was reported more frequently for cardiac ultrasound than for general ultrasound (108 [37.1%] vs 127 [16.5%], P < .001) and (170 [58.4%] vs 270 [35.1%], P < .001). Assessment of the inferior vena cava for fluid status emerged as the critical care ultrasound application associated with the greatest impact on management.

CONCLUSION

Point-of-care ultrasonography has the potential to optimize care of the critically ill patients when added to the clinical armamentarium of the intensive care physician.

Hemodynamic assessment of ventilated ICU patients with cardiorespiratory failure using a miniaturized multiplane transesophageal echocardiography probe

PURPOSE

To assess the feasibility, image quality, diagnostic accuracy, therapeutic impact and tolerance of diagnostic and hemodynamic assessment using a novel miniaturized multiplane transesophageal echocardiography (TEE) probe in ventilated ICU patients with cardiopulmonary compromise.

STUDY DESIGN

Prospective, descriptive, single-center study.

METHODS

Fifty-seven ventilated patients with acute circulatory or respiratory failure were assessed, using a miniaturized multiplane TEE probe and a standard TEE probe used as reference, randomly by two independent experienced operators. Measurements of hemodynamic parameters were independently performed off-line by a third expert. Diagnostic groups of acute circulatory failure (n = 5) and of acute respiratory failure (n = 3) were distinguished. Hemodynamic monitoring was performed in 9 patients using the miniaturized TEE probe. TEE tolerance and therapeutic impact were reported.

RESULTS

The miniaturized TEE probe was easier to insert than the standard TEE probe. Despite lower imaging quality of the miniaturized TEE probe, the two probes had excellent diagnostic agreement in patients with acute circulatory failure (Kappa: 0.95; 95% CI: 0.85-1) and with acute respiratory failure (Kappa: 1; 95% CI: 1.0-1.0). Accordingly, therapeutic strategies derived from both TEE examinations were concordant (Kappa: 0.82; 95% CI: 0.66-0.97). The concordance between quantitative hemodynamic parameters obtained with both TEE probes was also excellent. No relevant complication secondary to TEE probes insertion occurred.

CONCLUSIONS

Hemodynamic assessment of ventilated ICU patients with cardiopulmonary compromise using a miniaturized multiplane TEE probe appears feasible, well-tolerated, and relevant in terms of diagnostic information and potential therapeutic impact. Further larger-scale studies are needed to confirm these preliminary results.

Integrated use of bedside lung ultrasound and echocardiography in acute respiratory failure: a prospective observational study in ICU

BACKGROUND

It has been suggested that the complementary use of echocardiography could improve the diagnostic accuracy of lung ultrasonography (LUS) in patients with acute respiratory failure (ARF). Nevertheless, the additional diagnostic value of echocardiographic data when coupled with LUS is still debated in this setting. The aim of the current study was to compare the diagnostic accuracy of LUS and an integrative cardiopulmonary ultrasound approach (thoracic ultrasonography [TUS]) in patients with ARF.

METHODS

We prospectively recruited patients consecutively admitted for ARF to the ICU of a university teaching hospital over a 12-month period. Inclusion criteria were age ≥ 18 years and the presence of criteria for severe ARF justifying ICU admission. We compared both LUS and TUS approaches and the final diagnosis determined by a panel of experts using machine learning methods to improve the accuracy of the final diagnostic classifiers.

RESULTS

One hundred thirty-six patients were included (age, 68 ± 15 years; sex ratio, 1). A three-dimensional partial least squares and multinomial logistic regression model was developed and subsequently tested in an independent sample of patients. Overall, the diagnostic accuracy of TUS was significantly greater than LUS (P < .05, learning and test sample). Comparisons between receiver operating characteristic curves showed that TUS significantly improves the diagnosis of cardiogenic edema (P < .001, learning and test samples), pneumonia (P < .001, learning and test samples), and pulmonary embolism (P < .001, learning sample).

CONCLUSIONS

This study demonstrated for the first time to our knowledge a significantly better performance of TUS than LUS in the diagnosis of ARF. The value of the TUS approach was particularly important to disambiguate cases of hemodynamic pulmonary edema and pneumonia. We suggest that the bedside use of artificial intelligence methods in this setting could pave the way for the development of new clinically relevant integrative diagnostic models.

Can we predict poor hemodynamic tolerance of intermittent hemodialysis with echocardiography in intensive care patients?

OBJECTIVES

Tolerance of intermittent hemodialysis is potentially poor for patients hospitalized in the intensive care unit, particularly those in shock. The aim of this study was to determine whether an evaluation of the hemodynamic state by echocardiography before an intermittent hemodialysis session could predict tolerance during the session.

METHODS

Before an intermittent hemodialysis session, transesophageal echocardiography was performed on sedated patients, and transthoracic echocardiography was performed on nonsedated patients. Poor tolerance during intermittent hemodialysis was defined by the following criteria: greater than 20% decrease in mean arterial pressure, need for fluid loading (≥500 mL), a 15% increase in catecholamine if the dose was stable before the session or doubling the speed of catecholamine infusion if necessary, arrhythmia, and the necessity to stop the session before its prescribed end.

RESULTS

A total of 54 patients were included: 20 (37%) were intubated under controlled mechanical ventilation (group 1) and underwent transesophageal echocardiography; 14 (26%) were intubated under pressure support ventilation (group 2) and underwent transthoracic echocardiography; and 20 (37%) had no ventilation support (group 3). Twenty-four patients (46%) had poor tolerance criteria. A comparison of groups showed no significant difference in tolerance. Similarly, there was no difference with and without ultrafiltration. Increased respiratory variation of the vena cava was not predictive of poor tolerance in groups 1 and 2. In group 3, there was greater variation in patients with poor tolerance. In patients receiving mechanical ventilation, greater respiratory variability of the maximum velocity measured in the pulmonary artery was predictive of poor tolerance.

CONCLUSIONS

The hemodynamic profile of patients receiving mechanical ventilation was unable to predict tolerance of an intermittent hemodialysis session. In patients without mechanical ventilation, hypovolemia before the session appeared to be predictive of poor tolerance.

Interest of low-dose hydrocortisone therapy during brain-dead organ donor resuscitation: the CORTICOME study

Introduction

Circulatory failure during brain death organ donor resuscitation is a problem that compromises recovery of organs. Combined administration of steroid, thyroxine and vasopressin has been proposed to optimize the management of brain deceased donors before recovery of organs. However the single administration of hydrocortisone has not been rigorously evaluated in any trial.

Methods

In this prospective multicenter cluster study, 259 subjects were included. Administration of low-dose steroids composed the steroid group (n = 102).

Results

Although there were more patients in the steroid group who received norepinephrine before brain death (80% vs. 66%: P = 0.03), mean dose of vasopressor administered after brain death was significantly lower than in the control group (1.18 ± 0.92 mg/H vs. 1.49 ± 1.29 mg/H: P = 0.03), duration of vasopressor support use was shorter (874 min vs. 1160 min: P < 0.0001) and norepinephrine weaning before aortic clamping was more frequent (33.8% vs. 9.5%: P < 0.0001). Using a survival approach, probability of norepinephrine weaning was significantly different between the two groups (P < 0.0001) with a probability of weaning 4.67 times higher in the steroid group than in the control group (95% CI: 2.30 – 9.49).

Conclusions

Despite no observed benefits of the steroid administration on primary function recovery of transplanted grafts, administration of glucocorticoids should be a part of the resuscitation management of deceased donors with hemodynamic instability.

Prospective assessment of a score for assessing basic critical-care transthoracic echocardiography skills in ventilated critically ill patients

Background

We studied a score for assessing basic transthoracic echocardiography (TTE) skills exhibited by residents who examined critically ill patients receiving mechanical ventilation.

Methods

We conducted a prospective study in the 16 residents who worked in our medical-surgical ICU between 1 May 2008 and 1 November 2009. The residents received theoretical teaching (two hours) then performed supervised TTEs during their six-month rotation. Their basic TTE skills in mechanically ventilated patients were evaluated after one (M1), three (M3), and six (M6) months by two experts, who used a scoring system devised for the study. After scoring, residents gave their hemodynamic diagnosis and suggested a treatment.

Results

The 4 residents with previous TTE skills obtained a significantly higher total score than did the 12 novices at M1 (18 (16 to 19) versus 13 (10 to 15), respectively, P = 0.03). In the novices, the total score increased significantly during training (M1, 13 (10 to 14); M3, 15 (12 to 16); and M6, 17 (15 to 18); P < 0.001) and correlated significantly with the number of supervised TTEs (r = 0.68, P < 0.0001). In the overall population, agreement with experts regarding the diagnosis and treatment was associated with a significantly higher total score (17 (16 to 18) versus 13 (12 to 16), P = 0.002). A total score ≥ 19/20 points had 100% specificity (95% confidence interval, 79 to 100%) for full agreement with the experts regarding the diagnosis and treatment.

Conclusions

Our results validate the scoring system developed for our study of the assessment of basic critical-care TTE skills in residents.

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.

Hypoxic hepatitis in cardiac intensive care unit: a study of cardiovascular risk factors, clinical course, and outcomes

Introduction

Hypoxic hepatitis (HH) is observed frequently in intensive care units. Information in the cardiac intensive care unit (CICU) is limited. The aim of this study was to analyze the clinical course and outcomes of HH in the specific setting of the CICU.

Methods

We analyzed records of patients with HH admitted to the CICU (Group 1). Data were collected and compared with those of an intermediate group of patients with altered liver test results that did not meet the HH criteria who had a serum aminotransferase level of five to ≤20 times the upper-normal limit (Group 2), and with a control group who had an aminotransferase level less than five times the upper-normal limit (Group 3).

Results

Patients with HH exhibited a worse hemodynamic profile and more of these patients were in shock: 17 (94.4%) in Group 1, 14 (77.8%) in Group 2, and seven (38.9%) in Group 3 (P=0.001). Cardiogenic shock was the most frequent event: 12 (66.7%) in Group 1, 13 (72.2%) in Group 2, and six (33.3%) in Group 3 (P=0.006). The mortality rate was 55.6%. Mechanical ventilation was an independent factor associated with death (odds ratio 12.25, 95% confidence interval 1.26–118.36).

Conclusion

The mortality rate of patients with HH in CICU is high and is associated with ventilatory disturbances.

Optimizing perioperative hemodynamics: what is new?

PURPOSE OF REVIEW

Using perioperative goal-directed therapy (GDT) or peroperative hemodynamic optimization significantly reduces postoperative complications and risk of death in patients undergoing noncardiac major surgeries. In this review, we discuss the main changes in the field of perioperative optimization over the last few years.

RECENT FINDINGS

One of the key aspects that has changed in the last decade is the shift from invasive monitoring with pulmonary artery catheters (PACs) to less or minimally invasive monitoring systems. The evaluation of intravascular fluid volume deficits has also changed dramatically from the use of static indices to the assessment of fluid responsiveness using either dynamic indices or functional hemodynamic. Finally, attention has been directed toward more restrictive strategies of crystalloids as maintenance fluids.

SUMMARY

GDT is safe and more likely to tailor the amount of fluids given to the amount of fluids actually needed. This approach includes assessment of fluid responsiveness and, if necessary, the use of inotropes; moreover, this approach can be coupled with a restrictive strategy for maintenance fluids. These strategies have been increasingly incorporated into protocols for perioperative hemodynamic optimization in high-risk patients undergoing major surgery, resulting in more appropriate use of fluids, vasopressors, and inotropes.

Focused cardiac ultrasound: a training course for pediatric intensivists and emergency physicians

BACKGROUND

Focused echocardiographic examinations performed by intensivists and emergency room physicians can be a valuable tool for diagnosing and managing the hemodynamic status of critically ill children. The aim of this study was to evaluate the learning curve achieved using a theoretical and practical training program designed to enable pediatric intensivists and emergency physicians to conduct targeted echocardiograms.

METHODS

Theoretical and practical training sessions were conducted with 16 pediatric intensivist/emergency room physicians. The program included qualitative analyses of the left ventricular (LV) and right ventricular (RV) functions, evaluation of pericardial effusion/cardiac tamponade and valvular regurgitation and measurements of the distensibility index of the inferior vena cava (dIVC), ejection fraction (EF) and cardiac index (CI). The practical training sessions were conducted in the intensive care unit; each student performed 24 echocardiograms. The students in training were evaluated in a practical manner, and the results were compared with the corresponding examinations performed by experienced echocardiographers. The evaluations occurred after 8, 16 and 24 practical examinations.

RESULTS

The concordance rates between the students and echocardiographers in the subjective analysis of the LV function were 81.3% at the first evaluation, 96.9% at the second evaluation and 100% at the third evaluation (p < 0.001). For the dIVC, we observed a concordance of 46.7% at the first evaluation, 90.3% at the second evaluation and 87.5% at the third evaluation (p = 0.004). The means of the differences between the students' and echocardiographers' measurements of the EF and CI were 7% and 0.56 L/min/m2, respectively, after the third stage of training.

CONCLUSIONS

The proposed training was demonstrated to be sufficient for enabling pediatric physicians to analyze subjective LV function and to measure dIVC, EF and CI. This training course should facilitate the design of other echocardiography training courses that could be implemented in medical residency programs to improve these physicians' technical skills and the care of critically ill patients.

Usefulness of cardiothoracic chest ultrasound in the management of acute respiratory failure in critical care practice

BACKGROUND

This study investigated the clinical relevance of early general chest ultrasonography (ie, heart and lung recordings) in patients in the ICU with acute respiratory failure (ARF).

METHODS

We prospectively compared this diagnostic approach (ultrasound) to a routine evaluation established from clinical, radiologic, and biologic data (standard). Subjects were patients consecutively admitted to the ICU of a university teaching hospital during a 1-year period. Inclusion criteria were age ≥ 18 years and the presence of severe ARF criteria to justify ICU admission. We compared the diagnostic approaches and the final diagnosis determined by a panel of experts.

RESULTS

Seventy-eight patients were included (age, 70 ± 18 years; sex ratio, 1). Three patients given two or more simultaneous diagnoses were subsequently excluded. The ultrasound approach was more accurate than the standard approach (83% vs 63%, respectively; P &lt; .02). Receiver operating characteristic curve analysis showed greater diagnostic performance of ultrasound in cases of pneumonia (standard, 0.74 ± 0.12; ultrasound, 0.87 ± 0.14; P &lt; .02), acute hemodynamic pulmonary edema (standard, 0.79 ± 0.11; ultrasound, 0.93 ± 0.08; P &lt; .007), decompensated COPD (standard, 0.8 ± 0.09; ultrasound, 0.92 ± 0.15; P &lt; .05), and pulmonary embolism (standard, 0.65 ± 0.12; ultrasound, 0.81 ± 0.17; P &lt; .04). Furthermore, we found that the use of ultrasound data could have significantly improved the initial treatment.

CONCLUSIONS

The use of cardiothoracic ultrasound appears to be an attractive complementary diagnostic tool and seems able to contribute to an early therapeutic decision based on reproducible physiopathologic data.

Influence of positive end-expiratory pressure on myocardial strain assessed by speckle tracking echocardiography in mechanically ventilated patients

Purpose. The effects of mechanical ventilation (MV) on speckle tracking echocardiography- (STE-)derived variables are not elucidated. The aim of the study was to evaluate the effects of positive end-expiratory pressure (PEEP) ventilation on 4-chamber longitudinal strain (LS) analysis by STE. Methods. We studied 20 patients admitted to a mixed intensive care unit who required intubation for MV and PEEP titration due to hypoxia. STE was performed at three times: (T1) PEEP = 5 cmH₂O; (T2) PEEP = 10 cmH₂O; and (T3) PEEP = 15 cmH₂O. STE analysis was performed offline using a dedicated software (XStrain MyLab 70 Xvision, Esaote). Results. Left peak atrial-longitudinal strain (LS) was significantly reduced from T1 to T2 and from T2 to T3 (P < 0.05). Right peak atrial-LS and right ventricular-LS showed a significant reduction only at T3 (P < 0.05). Left ventricular-LS did not change significantly during titration of PEEP. Cardiac chambers' volumes showed a significant reduction at higher levels of PEEP (P < 0.05). Conclusions. We demonstrated for the first time that incremental PEEP affects myocardial strain values obtained with STE in intubated critically ill patients. Whenever performing STE in mechanically ventilated patients, care must be taken when PEEP is higher than 10 cmH₂O to avoid misinterpreting data and making erroneous decisions.

Utility of echocardiography in hypotension in the intensive care unit

A prospective study was performed on the utility of echocardiography in diagnosing hypotension in critically ill patients. In our study, we found that transthoracic echocardiography can help physicians determine the etiology of hypotension in a significant number of patients. Transesophageal echocardiography is useful when results obtained from transthoracic echocardiography are suboptimal. Left ventricular function assessed by echocardiography can be used to predict 30-day mortality.

Doppler resistive index to reflect regulation of renal vascular tone during sepsis and acute kidney injury

INTRODUCTION

Renal resistive index (RI), determined by Doppler ultrasonography, directly reveals and quantifies modifications in renal vascular resistance. The aim of this study was to evaluate if mean arterial pressure (MAP) is determinant of renal RI in septic, critically ill patients suffering or not from acute kidney injury (AKI).

METHODS

This prospective observational study included 96 patients. AKI was defined according to RIFLE criteria and transient or persistent AKI according to renal recovery within 3 days.

RESULTS

Median renal RIs were 0.72 (0.68-0.75) in patients without AKI and 0.76 (0.72-0.80) in patients with AKI (P = 0.001). RIs were 0.75 (0.72-0.79) in transient AKI and 0.77 (0.70-0.80) in persistent AKI (P = 0.84). RI did not differ in patients given norepinephrine infusion and was not correlated with norepinephrine dose. RI was correlated with MAP (ρ = -0.47; P = 0.002), PaO2/FiO2 ratio (ρ = -0.33; P = 0.04) and age (ρ = 0.35; P = 0.015) only in patients without AKI.

CONCLUSIONS

A poor correlation between renal RI and MAP, age, or PaO2/FiO2 ratio was found in septic and critically ill patients without AKI compared to patients with AKI. These findings suggest that determinants of RI are multiple. Renal circulatory response to sepsis estimated by Doppler ultrasonography cannot reliably be predicted simply from changes in systemic hemodynamics. As many factors influence its value, the interest in a single RI measurement at ICU admission to determine optimal MAP remains uncertain.

[Role of echocardiography in the hemodynamic monitorization of critical patients]

The use of echocardiography in intensive care units in shock patients allows us to measure various hemodynamic variables in an accurate and a non-invasive manner. By using echocardiography not only as a diagnostic technique but also as a tool for continuous hemodynamic monitorization, the intensivist can evaluate various aspects of shock states, such as cardiac output and fluid responsiveness, myocardial contractility, intracavitary pressures, heart-lung interaction and biventricular interdependence. However, to date there has been little guidance orienting echocardiographic hemodynamic parameters in the intensive care unit, and intensivists are usually not familiar with this tool. In this review, we describe some of the most important hemodynamic parameters that can be obtained at the patient bedside with transthoracic echocardiography in critically ill patients.

Review article: Part one: Goal-directed resuscitation--which goals? Haemodynamic targets

The use of appropriate resuscitation targets or end-points may facilitate early detection and appropriate management of shock. There is a fine balance between oxygen delivery and consumption, and when this is perturbed, an oxygen debt is generated. In this narrative review, we explore the value of global haemodynamic resuscitation end-points, including pulse rate, blood pressure, central venous pressure and mixed/central venous oxygen saturations. The evidence supporting the reliability of these parameters as end-points for guiding resuscitation and their potential limitations are evaluated.

Echocardiography in the sepsis syndromes

Purpose of the review

Non-invasiveness and instantaneous diagnostic capability are prominent features of the use of echocardiography in critical care. Sepsis and septic shock represent complex situations where early hemodynamic assessment and support are among the keys to therapeutic success. In this review, we discuss the range of applications of echocardiography in the management of the septic patient, and propose an echocardiography-based goal-oriented hemodynamic approach to septic shock.

Recent findings

Echocardiography can play a key role in the critical septic patient management, by excluding cardiac causes for sepsis, and mostly by guiding hemodynamic management of those patients in whom sepsis reaches such a severity to jeopardize cardiovascular function. In recent years, there have been both increasing evidence and diffusion of the use of echocardiography as monitoring tool in the patients with hemodynamic compromise. Also thanks to echocardiography, the features of the well-known sepsis-related myocardial dysfunction have been better characterized. Furthermore, many of the recent echocardiographic indices of volume responsiveness have been validated in populations of septic shock patients.

Conclusion

Although not proven yet in terms of patient outcome, echocardiography can be regarded as an ideal monitoring tool in the septic patient, as it allows (a) first line differential diagnosis of shock and early recognition of sepsis-related myocardial dysfunction; (b) detection of pre-existing cardiac pathology, that yields precious information in septic shock management; (c) comprehensive hemodynamic monitoring through a systematic approach based on repeated bedside assessment; (d) integration with other monitoring devices; and (e) screening for cardiac source of sepsis.

Transthoracic focused rapid echocardiographic examination: real-time evaluation of fluid status in critically ill trauma patients

BACKGROUND

A transthoracic focused rapid echocardiographic evaluation (FREE) was developed to answer specific questions about treatment direction regarding the use of fluid versus ionotropes in trauma patients. Our objective was to evaluate the clinical utility of the information obtained by this diagnostic test.

METHODS

The FREE was performed by an ultrasonographer or an intensivist and interpreted by a surgical intensivist using a full service portable echo machine (Vivid i; GE Healthcare). The clinical team ordering the examination was surveyed before and after the test was performed.

RESULTS

During a 9-month study period, the FREE was performed in 53 patients admitted to our trauma critical care units. In 80% of patients, an estimated ejection fraction was obtained. Moderate and severe left ventricular dysfunction was diagnosed in 56% of patients, and right heart dysfunction was found in 25% of the patients. Inferior vena cava (IVC) diameter and IVC respiratory variation was visualized in 80% of patients. In 87% (46 of 53), the FREE was able to answer the clinical question asked by the primary team. Strikingly, in 54% of patients, the plan of care was modified as a result of the FREE examination.

CONCLUSIONS

IVC diameter and IVC respiratory variation was able to be obtained in the majority of cases, giving an estimate of fluid status. Estimation of ejection fraction was useful in guiding the treatment plan regarding the requirement of fluid boluses versus ionotropic support. We conclude that the FREE can provide meaningful data in difficult to image critically ill trauma patients.

Cardiac function index provided by transpulmonary thermodilution behaves as an indicator of left ventricular systolic function

OBJECTIVE

To test whether cardiac function index could actually behave as an indicator of left ventricular systolic function by testing if 1) it increased with inotropic stimulation; 2) it was not altered by fluid loading; 3) it correlated with the echographic left ventricular ejection fraction, considered as the clinical gold standard for measuring left ventricular systolic function, and it reliably tracked the changes in left ventricular ejection fraction during therapeutic intervention. The transpulmonary thermodilution calculates the cardiac function index, which is the ratio of cardiac output over global end-diastolic volume.

DESIGN

Prospective study.

SETTING

Medical intensive care unit of a university hospital.

PATIENTS

Thirty-nine patients (n = 48 cases) with acute circulatory failure.

INTERVENTION

A 500-mL saline administration (n = 24 cases) and a dobutamine infusion (n = 24 cases).

MEASUREMENTS AND MAIN RESULTS

We simultaneously measured left ventricular ejection fraction (monoplane or biplane Simpson method) and cardiac function index at baseline and after saline and dobutamine administration. As volume expansion altered neither left ventricular ejection fraction (47 +/- 11% to 47 +/- 11%) nor cardiac function index (4.5 +/- 2.2 to 4.5 +/- 2.1 min(-1)), dobutamine infusion significantly increased left ventricular ejection fraction by 32 +/- 28% and cardiac function index by 29 +/- 22%. Considering the 96 cardiac function index:left ventricular ejection fraction pairs of measurements, cardiac function index and left ventricular ejection fraction were correlated significantly (r = .67, p < .05). A cardiac function index <3.2 min(-1) predicted a left ventricular ejection fraction of <35% with a sensitivity of 81% and a specificity of 88%. Importantly, the changes in left ventricular ejection fraction and in cardiac function index during fluid and dobutamine administration were correlated significantly (r = .79, p < .05).

CONCLUSIONS

Cardiac function index fulfilled the criteria required from a clinical indicator of left ventricular global systolic function. Thus, it could serve as an easy bedside detection of the alteration in left ventricular ejection fraction that should alert the physician and incite to perform an echocardiography. Furthermore, cardiac function index tracked accurately the effects of an inotropic therapy.

Development and application of a logistic-based systolic model for hemodynamic measurements using the esophageal Doppler monitor

The esophageal Doppler monitor (EDM) is a clinically useful device for minimally invasive assessment of cardiac output, preload, afterload, and contractility. An empirical model, based upon the logistic function, has been developed. Use of this model illustrates how the EDM could estimate the net effect of aortic and non-aortic contributions to inertia, resistance, and elastance within real time. This is based on an assumed mechanical impedance conceptually resembling that of a series arrangement of a spring, mass, and dashpot. In addition, when used with an invasive radial arterial catheter, the EDM may also estimate aortic pulse wave velocity, as well as aortic characteristic impedance, and characteristic volume. Approximations of left ventricular stroke work and stroke power can also be made. Furthermore, the effects of inertia, resistance, and elastance, on mean blood pressure during systole, can be quantified. These additional parameters could offer insight for clinicians, as well as researchers, and may be beneficial in further examining and utilizing clinical hemodynamics with the EDM. These additional measurements also underscore the need to integrate the EDM with existing and future monitoring equipment.

Echocardiography practice, training and accreditation in the intensive care: document for the World Interactive Network Focused on Critical Ultrasound (WINFOCUS)

Echocardiography is increasingly used in the management of the critically ill patient as a non-invasive diagnostic and monitoring tool. Whilst in few countries specialized national training schemes for intensive care unit (ICU) echocardiography have been developed, specific guidelines for ICU physicians wishing to incorporate echocardiography into their clinical practice are lacking. Further, existing echocardiography accreditation does not reflect the requirements of the ICU practitioner. The WINFOCUS (World Interactive Network Focused On Critical UltraSound) ECHO-ICU Group drew up a document aimed at providing guidance to individual physicians, trainers and the relevant societies of the requirements for the development of skills in echocardiography in the ICU setting. The document is based on recommendations published by the Royal College of Radiologists, British Society of Echocardiography, European Association of Echocardiography and American Society of Echocardiography, together with international input from established practitioners of ICU echocardiography. The recommendations contained in this document are concerned with theoretical basis of ultrasonography, the practical aspects of building an ICU-based echocardiography service as well as the key components of standard adult TTE and TEE studies to be performed on the ICU. Specific issues regarding echocardiography in different ICU clinical scenarios are then described. Obtaining competence in ICU echocardiography may be achieved in different ways - either through completion of an appropriate fellowship/training scheme, or, where not available, via a staged approach designed to train the practitioner to a level at which they can achieve accreditation. Here, peri-resuscitation focused echocardiography represents the entry level--obtainable through established courses followed by mentored practice. Next, a competence-based modular training programme is proposed: theoretical elements delivered through blended-learning and practical elements acquired in parallel through proctored practice. These all linked with existing national/international echocardiography courses. When completed, it is anticipated that the practitioner will have performed the prerequisite number of studies, and achieved the competency to undertake accreditation (leading to Level 2 competence) via a recognized National or European examination and provide the appropriate required evidence of competency (logbook). Thus, even where appropriate fellowships are not available, with support from the relevant echocardiography bodies, training and subsequently accreditation in ICU echocardiography becomes achievable within the existing framework of current critical care and cardiological practice, and is adaptable to each countrie's needs.

Assessment of moderate to severe abdominal blood loss using peripheral to central blood oxygen saturation

PURPOSE

There are various definitions and monitoring modalities for hemodynamic status. Each of them has its own advantages and shortcomings. A new hemodynamic index is proposed in this study. This index can be calculated by placing the measured hemoglobin saturation in a formula. Blood samples for this measurement are taken from arterial, antecubital and central venous blood.

MATERIAL AND METHODS

We calculated this index in three different groups undergoing laparatomy. The control group consisted of patients who underwent elective surgery. The case group with acute internal abdominal bleeding was divided into two groups. Those with more than 20 ml/kg of blood in their abdominal cavity were designated as the severe case group, while those bleeding less were categorized as moderate. Blood samples were taken from ten patients in each group in stable and unstable conditions.

RESULTS

This index differed significantly between dissimilar hemodynamic conditions. The pre-anesthesia value of this index in the control group showed a mean +/- SD of 8.5 +/- 3.2 vs. 1.6 +/- 0.4 in the moderate case group vs. 0.7 +/- 0.08 in the case group with severe hemodynamic changes (p < .001). The index approximated to the control values as the circumstances improved. After compensation for volume loss, pre-extubation values were not significantly different. These were 9.6 +/- 2 in the control group vs. 8 +/- 2 in the case group with moderate hemodynamic change vs. 8 +/- 1.8 in the severe case group. The likelihood ratio of bleeding increased as this index decreased.

CONCLUSION

As the hemodynamic condition deteriorates, this index decreases significantly. This index is an accurate indicator for predicting hemodynamic changes compared to some other modalities. Further investigations are needed into the prognostic and therapeutic advantages of this index.

Inferior vena cava diameter correlates with invasive hemodynamic measures in mechanically ventilated intensive care unit patients with sepsis

Early optimization of fluid status is of central importance in the treatment of critically ill patients. This study aims to investigate whether inferior vena cava (IVC) diameters correlate with invasively assessed hemodynamic parameters and whether this approach may thus contribute to an early, non-invasive evaluation of fluid status. Thirty mechanically ventilated patients with severe sepsis or septic shock (age 60 +/- 15 years; APACHE-II score 31 +/- 8; 18 male) were included. IVC diameters were measured throughout the respiratory cycle using transabdominal ultrasonography. Consecutively, volume-based hemodynamic parameters were determined using the single-pass thermal transpulmonary dilution technique. This was a prospective study in a tertiary care academic center with a 24-bed medical intensive care unit (ICU) and a 14-bed anesthesiological ICU. We found a statistically significant correlation of both inspiratory and expiratory IVC diameter with central venous pressure (p = 0.004 and p = 0.001, respectively), extravascular lung water index (p = 0.001, p < 0.001, respectively), intrathoracic blood volume index (p = 0.026, p = 0.05, respectively), the intrathoracic thermal volume (both p < 0.001), and the PaO(2)/FiO(2) oxygenation index (p = 0.007 and p = 0.008, respectively). In this study, IVC diameters were found to correlate with central venous pressure, extravascular lung water index, intrathoracic blood volume index, the intrathoracic thermal volume, and the PaO(2)/FiO(2) oxygenation index. Therefore, sonographic determination of IVC diameter seems useful in the early assessment of fluid status in mechanically ventilated septic patients. At this point in time, however, IVC sonography should be used only in addition to other measures for the assessment of volume status in mechanically ventilated septic patients.

Echocardiographic assessment of pulmonary artery occlusion pressure in ventilated patients: a transoesophageal study

Background

Non-invasive evaluation of left ventricular filling pressure has been scarcely studied in critically ill patients. Accordingly, we prospectively assessed the ability of transoesophageal echocardiography (TEE) Doppler to predict an invasive pulmonary artery occlusion pressure (PAOP) ≤ 18 mmHg in ventilated patients.

Methods

During two consecutive 3-year periods, TEE Doppler parameters were compared to right heart catheterisation derived PAOP used as reference in 88 ventilated patients, haemodynamically stable and in sinus rhythm (age: 63 ± 14 years; simplified acute physiologic score (SAPS) II: 45 ± 12). During the initial period (protocol A), threshold values of pulsed-wave Doppler parameters to predict an invasive PAOP ≤ 18 mmHg were determined in 56 patients. Derived Doppler values were prospectively tested during the subsequent period (protocol B) in 32 patients.

Results

In protocol A, Doppler parameters had similar area under the receiver operating characteristic (ROC) curve. In protocol B, mitral E/A ≤ 1.4, pulmonary vein S/D > 0.65 and systolic fraction > 44% best predicted an invasive PAOP ≤ 18 mmHg. Lateral E/E' ≤ 8.0 or E/Vp ≤ 1.7 predicted a PAOP ≤ 18 mmHg with a sensitivity of 83% and 80%, and a specificity of 88% and 100%, respectively. Areas under ROC curves of lateral E/E' and E/Vp were similar (0.91 ± 0.07 vs 0.92 ± 0.07: p = 0.53), and not significantly different from those of pulsed-wave Doppler indices.

Conclusion

TEE accurately predicts invasive PAOP ≤ 18 mmHg in ventilated patients. This further increases its diagnostic value in patients with suspected acute lung injury/acute respiratory distress syndrome.

Cardiac morphological and functional changes during early septic shock: a transesophageal echocardiographic study

OBJECTIVE

The objective was to prospectively evaluate cardiac morphological and functional changes using transesophageal echocardiography (TEE) during early septic shock.

DESIGN

Prospective, observational study.

SETTING

Medical-surgical intensive care unit of a teaching hospital.

PATIENTS AND PARTICIPANTS

Ventilated patients with septic shock, sinus rhythm and no cardiac disease underwent TEE within 12h of admission (Day0), after stabilization of hemodynamics by fluid loading (median volume: 4.9l [lower and upper quartiles: 3.7-9.6l]) and vasopressor therapy, and after vasopressors were stopped (Dayn).

MEASUREMENTS AND RESULTS

Thirty-five patients were studied (median age: 60 years [range 44-68]; SAPS II: 53 [46-62]; SOFA score: 9 [8-11]) and 9 of them (26%) died while on vasopressors. None of the patients exhibited TEE findings of cardiac preload dependence. Between Day0 and Dayn (7 days [range 6-9]), mean left ventricular (LV) ejection fraction (EF) increased (47 +/- 20 vs. 57 +/- 14%: p < 0.05), whereas mean LV end-diastolic volume decreased (97 +/- 25 vs. 75 +/- 20ml: p < 0.0001). Out of 16 patients (46%) with LV systolic dysfunction on Day0, 12 had normal LVEF on Dayn and 4 patients fully recovered by Day28. Only 4 women had LV dilatation (range, LV end-diastolic volume: 110-148ml) on Day0, but none on Dayn. Doppler tissue imaging identified an LV diastolic dysfunction in 7 patients (20%) on Day0 (3 with normal LVEF), which resolved on Dayn.

CONCLUSIONS

This study confirms that LV systolic and diastolic dysfunctions are frequent, but LV dilatation is uncommon in fluid-loaded septic patients on vasopressors. All abnormalities regressed in survivors, regardless of their severity.

DESCRIPTORS

Shock: clinical studies (38), Cardiovascular monitoring (34).

Focused training for goal-oriented hand-held echocardiography performed by noncardiologist residents in the intensive care unit

OBJECTIVE

We sought to evaluate the efficacy of a limited training dedicated to residents without knowledge in ultrasound for performing goal-oriented echocardiography in ICU patients.

DESIGN

Prospective pilot observational study.

SETTING

Medical-surgical ICU of a teaching hospital.

PATIENTS

61 consecutive adult ICU patients (SAPS II score: 38 +/- 17; 46 ventilated patients) requiring a transthoracic echocardiography were studied.

INTERVENTIONS

After a curriculum including a 3-h training course and 5 h of hands-on training, one of four noncardiologist residents and an intensivist experienced in ultrasound subsequently performed hand-held echocardiography (HHE), independently and in random order. Assessable "rule in, rule out" clinical questions were purposely limited to easily identifiable conditions by the sole use of two-dimensional imaging.

MEASUREMENTS AND RESULTS

When compared with residents, the experienced intensivist performed shorter examinations (4 +/- 1 vs. 11 +/- 4 min: p < 0.0001) and had significantly less unsolved clinical questions [3 (0.8%) vs. 27 (7.4%) of 366 clinical questions: p < 0.0001]. When addressed, clinical questions were adequately appraised by residents: left ventricular systolic dysfunction [Kappa: 0.76 +/- 0.09 (95% CI: 0.59-0.93)], left ventricular dilatation [Kappa: 0.66 +/- 0.12 (95% CI: 0.43-0.90)], right ventricular dilatation [Kappa: 0.71 +/- 0.12 (95% CI: 0.46-0.95)], pericardial effusion [Kappa: 0.68 +/- 0.18 (95 CI: 0.33-1.03)], and pleural effusion [Kappa: 0.71 +/- 0.09 (95% CI: 0.53-0.88)]. The only case of tamponade was accurately diagnosed by the resident.

CONCLUSIONS

Limited training of noncardiologist ICU residents without previous knowledge in ultrasound appears feasible and efficient to address simple clinical questions using point-of-care echography. Influence of the learning curve on diagnostic accuracy and potential therapeutic impact remain to be determined.

What role does the right side of the heart play in circulation?

Right ventricular failure (RVF) is an underestimated problem in intensive care. This review explores the physiology and pathophysiology of right ventricular function and the pulmonary circulation. When RVF is secondary to an acute increase in afterload, the picture is one of acute cor pulmonale, as occurs in the context of acute respiratory distress syndrome, pulmonary embolism and sepsis. RVF can also be caused by right myocardial dysfunction. Pulmonary arterial catheterization and echocardiography are discussed in terms of their roles in diagnosis and treatment. Treatments include options to reduce right ventricular afterload, specific pulmonary vasodilators and inotropes.

Echocardiographic prediction of volume responsiveness in critically ill patients with spontaneously breathing activity

OBJECTIVE

In hemodynamically unstable patients with spontaneous breathing activity, predicting volume responsiveness is a difficult challenge since the respiratory variation in arterial pressure cannot be used. Our objective was to test whether volume responsiveness can be predicted by the response of stroke volume measured with transthoracic echocardiography to passive leg raising in patients with spontaneous breathing activity. We also examined whether common echocardiographic indices of cardiac filling status are valuable to predict volume responsiveness in this category of patients.

DESIGN AND SETTING

Prospective study in the medical intensive care unit of a university hospital.

PATIENTS

24 patients with spontaneously breathing activity considered for volume expansion.

MEASUREMENTS

We measured the response of the echocardiographic stroke volume to passive leg raising and to saline infusion (500 ml over 15 min). The left ventricular end-diastolic area and the ratio of mitral inflow E wave velocity to early diastolic mitral annulus velocity (E/Ea) were also measured before and after saline infusion.

RESULTS

A passive leg raising induced increase in stroke volume of 12.5% or more predicted an increase in stroke volume of 15% or more after volume expansion with a sensitivity of 77% and a specificity of 100%. Neither left ventricular end-diastolic area nor E/Ea predicted volume responsiveness.

CONCLUSIONS

In our critically ill patients with spontaneous breathing activity the response of echocardiographic stroke volume to passive leg raising was a good predictor of volume responsiveness. On the other hand, the common echocardiographic markers of cardiac filling status were not valuable for this purpose.