Assessment of Right Ventricular Mechanics by 3D Transesophageal Echocardiography in the Early Phase of Acute Respiratory Distress Syndrome.

Aim: To compare global and axial right ventricular ejection fraction in ventilated patients for moderate-to-severe acute respiratory distress syndrome (ARDS) secondary to early SARS-CoV-2 pneumonia or to other causes, and in ventilated patients without ARDS used as reference. Methods: Retrospective single-center cross-sectional study including 64 ventilated patients: 21 with ARDS related to SARS-CoV-2 (group 1), 22 with ARDS unrelated to SARS-CoV-2 (group 2), and 21 without ARDS (control group). Real-time three-dimensional transesophageal echocardiography was performed for hemodynamic assessment within 24 h after admission. Contraction pattern of the right ventricle was decomposed along the three anatomically relevant axes. Relative contribution of each spatial axis was evaluated by calculating ejection fraction along each axis divided by the global right ventricular ejection fraction. Results: Global right ventricular ejection fraction was significantly lower in group 2 than in both group 1 and controls [median: 43% (25-75th percentiles: 40-57) vs. 58% (55-62) and 65% (56-68), respectively: p < 0.001]. Longitudinal shortening had a similar relative contribution to global right ventricular ejection fraction in all groups [group 1: 32% (28-39), group 2: 29% (24-40), control group: 31% (28-38), p = 0.6]. Radial shortening was lower in group 2 when compared to both group 1 and controls [45% (40-53) vs. 57% (51-62) and 56% (50-60), respectively: p = 0.005]. The relative contribution of right ventricular shortening along the anteroposterior axis was not statistically different between groups [group 1: 51% (41-55), group 2: 56% (46-63), control group; 56% (50-64), p = 0.076]. Conclusion: During early hemodynamic assessment, the right ventricular systolic function appears more impaired in ARDS unrelated to SARS-CoV-2 when compared to early stage SARS-CoV-2 ARDS. Radial shortening appears more involved than longitudinal and anteroposterior shortening in patients with ARDS unrelated to SARS-CoV-2 and decreased right ventricular ejection fraction.

The PRICES statement: an ESICM expert consensus on methodology for conducting and reporting critical care echocardiography research studies.

PURPOSE: Echocardiography is a common tool for cardiac and hemodynamic assessments in critical care research. However, interpretation (and applications) of results and between-study comparisons are often difficult due to the lack of certain important details in the studies. PRICES (Preferred Reporting Items for Critical care Echocardiography Studies) is a project endorsed by the European Society of Intensive Care Medicine and conducted by the Echocardiography Working Group, aiming at producing recommendations for standardized reporting of critical care echocardiography (CCE) research studies. METHODS: The PRICE panel identified lists of clinical and echocardiographic parameters (the "items") deemed important in four main areas of CCE research: left ventricular systolic and diastolic functions, right ventricular function and fluid management. Each item was graded using a critical index (CI) that combined the relative importance of each item and the fraction of studies that did not report it, also taking experts' opinion into account. RESULTS: A list of items in each area that deemed essential for the proper interpretation and application of research results is recommended. Additional items which aid interpretation were also proposed. CONCLUSION: The PRICES recommendations reported in this document, as a checklist, represent an international consensus of experts as to which parameters and information should be included in the design of echocardiography research studies. PRICES recommendations provide guidance to scientists in the field of CCE with the objective of providing a recommended framework for reporting of CCE methodology and results.

Right ventricular failure in septic shock: characterization, incidence and impact on fluid responsiveness.

OBJECTIVE: Incidence of right ventricular (RV) failure in septic shock patients is not well known, and tricuspid annular plane systolic excursion (TAPSE) could be of limited value. We report the incidence of RV failure in patients with septic shock, its potential impact on the response to fluids, as well as TAPSE values. DESIGN: Ancillary study of the HEMOPRED prospective multicenter study includes patients under mechanical ventilation with circulatory failure. SETTING: This is a multicenter intensive care unit study PATIENTS: Two hundred and eighty-two patients with septic shock were analyzed. Patients were classified in three groups based on central venous pressure (CVP) and RV size (RV/LV end-diastolic area, EDA). In group 1, patients had no RV dilatation (RV/LVEDA < 0.6). In group 2, patients had RV dilatation (RV/LVEDA ≥ 0.6) with a CVP < 8 mmHg (no venous congestion). RV failure was defined in group 3 by RV dilatation and a CVP ≥ 8 mmHg. Pulse pressure variation (PPV) was systematically recorded. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: In total, 41% of patients were in group 1, 17% in group 2 and 42% in group 3. A correlation between RV size and CVP was only observed in group 3. Higher RV size was associated with a lower response to passive leg raising for a given PPV. A large overlap of TAPSE values was observed between the 3 groups. 63.5% of patients with RV failure had a normal TAPSE. CONCLUSIONS: RV failure, defined by critical care echocardiography (RV dilatation) and a surrogate of venous congestion (CVP ≥ 8 mmHg), was frequently observed in septic shock patients and negatively associated with response to a fluid challenge despite significant PPV. TAPSE was unable to discriminate patients with or without RV failure.

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.

Assessment of volume status and volume responsiveness in the ICU: Protocol for an observational, multicentre cohort study.

BACKGROUND: Expansion of the intravascular compartment is common to treat haemodynamic instability in ICU patients. The most useful and accurate variables to guide and evaluate a fluid challenge remain debated and incompletely investigated resulting in significant variability in practice. The analogue mean systemic pressure has been reported as a measure of the intravascular volume state. METHODS: This is a protocol and statistical analysis plan for a review of the application of an analogue of the mean systemic pressure and the use of derived variables to assess the volume state and volume responsiveness. A pulmonary artery catheter was used in 286 postoperative cardiac surgical patients to monitor cardiac output before and after a fluid bolus in addition to arterial and central venous pressures. With otherwise similar monitoring, echocardiography was used in 540 general ICU patients to determine cardiac outputs and indices related to intravascular filling. The responses to a fluid bolus or the passive leg raising manoeuvre will be investigated using continuous and dichotomous definitions of volume responsiveness. The results will be stratified according to the method of monitoring cardiac output. CONCLUSIONS: This study investigating 2 cohorts that encompass a wide variety of reasons for haemodynamic instability will illustrate the applicability of the analogue mean systemic pressure and derived variables to assess the volume state and responsiveness. The results may guide the rationale and design of interventional studies.

Multicentric Standardized Flow Cytometry Routine Assessment of Patients With Sepsis to Predict Clinical Worsening.

BACKGROUND: In this study, we primarily sought to assess the ability of flow cytometry to predict early clinical deterioration and overall survival in patients with sepsis admitted in the ED and ICU. METHODS: Patients admitted for community-acquired acute sepsis from 11 hospital centers were eligible. Early (day 7) and late (day 28) deaths were notified. Levels of CD64pos granulocytes, CD16pos monocytes, CD16dim immature granulocytes (IGs), and T and B lymphocytes were assessed by flow cytometry using an identical, cross-validated, robust, and simple consensus standardized protocol in each center. RESULTS: Among 1,062 patients screened, 781 patients with confirmed sepsis were studied (age, 67 ± 48 years; Simplified Acute Physiology Score II, 36 ± 17; Sequential Organ Failure Assessment, 5 ± 4). Patients were divided into three groups (sepsis, severe sepsis, and septic shock) on day 0 and on day 2. On day 0, patients with sepsis exhibited increased levels of CD64pos granulocytes, CD16pos monocytes, and IGs with T-cell lymphopenia. Clinical severity was associated with higher percentages of IGs and deeper T-cell lymphopenia. IG percentages tended to be higher in patients whose clinical status worsened on day 2 (35.1 ± 35.6 vs 43.5 ± 35.2, P = .07). Increased IG percentages were also related to occurrence of new organ failures on day 2. Increased IG percentages, especially when associated with T-cell lymphopenia, were independently associated with early (P < .01) and late (P < .01) death. CONCLUSIONS: Increased circulating IGs at the acute phase of sepsis are linked to clinical worsening, especially when associated with T-cell lymphopenia. Early flow cytometry could help clinicians to target patients at high risk of clinical deterioration. TRIAL REGISTRY: ClinicalTrials.gov; No.: NCT01995448; URL: www.clinicaltrials.gov.

Hemodynamic Assessment of Patients With Septic Shock Using Transpulmonary Thermodilution and Critical Care Echocardiography: A Comparative Study.

BACKGROUND: To assess the agreement between transpulmonary thermodilution (TPT) and critical care echocardiography (CCE) in ventilated patients with septic shock. METHODS: Ventilated patients in sinus rhythm requiring advanced hemodynamic assessment for septic shock were included in this prospective multicenter descriptive study. Patients were assessed successively using TPT and CCE in random order. Data were interpreted independently at bedside by two investigators who proposed therapeutic changes on the basis of predefined algorithms. TPT and CCE hemodynamic assessments were reviewed offline by two independent experts who identified potential sources of discrepant results by consensus. Lactate clearance and outcome were studied. RESULTS: A total of 137 patients were studied (71 men; age, 61 ± 15 years; Simplified Acute Physiologic Score, 58 ± 18; Sequential Organ Failure Assessment, 10 ± 3). TPT and CCE interpretations at bedside were concordant in 87/132 patients (66%) without acute cor pulmonale (ACP), resulting in a moderate agreement (kappa, 0.48; 95% CI, 0.37-0.60). Experts' adjudications were concordant in 100/129 patients without ACP (77.5%), resulting in a good intertechnique agreement (kappa, 0.66; 95% CI, 0.55-0.77). In addition to ACP (n = 8), CCE depicted a potential source of TPT inaccuracy in 8/29 patients (28%). Lactate clearance at H6 was similar irrespective of the concordance of online interpretations of TPT and CCE (55/84 [65%] vs 32/45 [71%], P = .55). ICU and day 28 mortality rates were similar between patients with concordant and discordant interpretations (29/87 [36%] vs 13/45 [29%], P = .60; and 31/87 [36%] vs 16/45 [36%], P = .99, respectively). CONCLUSIONS: Agreement between TPT and CCE was moderate when interpreted at bedside and good when adjudicated offline by experts, but without impact on lactate clearance and mortality.

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.

Ultrasonographic identification and semiquantitative assessment of unloculated pleural effusions in critically ill patients by residents after a focused training.

PURPOSE: Chest ultrasonography is currently a required element to achieve competence in general critical care ultrasound (GCCUS) which should be part of the training of every intensivist. We sought to assess the ability of resident novices in ultrasonography to identify and quantify unloculated pleural effusions in ICU patients after a limited training program. METHODS: A total of 147 patients (mean age, 62 ± 17 years; simplified acute physiology score II, 35 ± 15; 78 % ventilated) with a suspected pleural effusion underwent a thoracic ultrasonography performed successively by a recently trained resident novice in ultrasound and by an experienced intensivist with expertise in GCCUS, considered as reference. Ultrasonographic examinations were performed randomly and independently. In the presence of a pleural effusion, the maximal interpleural distance was measured at the thoracic base. RESULTS: Residents performed a mean of 15 ± 9 examinations. Agreement between residents and experienced intensivists for the diagnosis of left- and right-sided pleural effusions was good to excellent [kappa 0.74 (95 % CI 0.63-0.85) and 0.86 (95 % CI 0.78-0.94), respectively)]. Agreement for the measurement of left and right maximal interpleural distance was excellent (intraclass concordance coefficient, 0.86 [95 % CI 0.77-0.91] and 0.85 [95 % CI 0.75-0.90], respectively). Mean bias for left and right interpleural distance was -0.3 mm (95 % CI -2.4, 1.8 mm) and -1.2 mm (95 % CI -3.4, 1.1 mm), respectively. CONCLUSIONS: After a focused training program, resident novices in ultrasound identify and quantify unloculated pleural effusions in ICU patients using chest ultrasonography with a good agreement with experts.

Initial resuscitation guided by the Surviving Sepsis Campaign recommendations and early echocardiographic assessment of hemodynamics in intensive care unit septic patients: a pilot study.

OBJECTIVE: To compare therapeutic interventions during initial resuscitation derived from echocardiographic assessment of hemodynamics and from the Surviving Sepsis Campaign guidelines in intensive care unit septic patients. DESIGN AND SETTING: Prospective, descriptive study in two intensive care units of teaching hospitals. METHODS: The number of ventilated patients with septic shock who were studied was 46. Transesophageal echocardiography was first performed (T1<3 hrs after intensive care unit admission) to adapt therapy according to the following predefined hemodynamic profiles: fluid loading (index of collapsibility of the superior vena cava≥36%), inotropic support (left ventricular fractional area change<45% without relevant index of collapsibility of the superior vena cava), or increased vasopressor support (right ventricular systolic dysfunction, unremarkable transesophageal echocardiography study consistent with sustained vasoplegia). Agreement for treatment decision between transesophageal echocardiography and Surviving Sepsis Campaign guidelines was evaluated. A second transesophageal echocardiography assessment (T2) was performed to validate therapeutic interventions. RESULTS: Although transesophageal echocardiography and Surviving Sepsis Campaign approaches were concordant to manage fluid loading in 32 of 46 patients (70%), echocardiography led to the absence of blood volume expansion in the remaining 14 patients who all had a central venous pressure<12 mm Hg. Accordingly, the agreement was weak between transesophageal echocardiography and Surviving Sepsis Campaign for the decision of fluid loading (κ: 0.37 [0.16;0.59]). With a cut-off value<8 mm Hg for central venous pressure, κ was 0.33 [-0.03;0.69]. Inotropes were prescribed based on transesophageal echocardiography assessment in 14 patients but would have been decided in only four patients according to Surviving Sepsis Campaign guidelines. As a result, the agreement between the two approaches for the decision of inotropic support was weak (κ: 0.23 [-0.04;0.50]). No right ventricular dysfunction was observed. No patient had anemia and only three patients with transesophageal echocardiography documented left ventricular systolic dysfunction had a central venous oxygen saturation<70%. CONCLUSIONS: A weak agreement was found in the prescription of fluid loading and inotropic support derived from early transesophageal echocardiography assessment of hemodynamics and Surviving Sepsis Campaign guidelines in patients presenting with septic shock.

Assessment of left ventricular ejection fraction using an ultrasonic stethoscope in critically ill patients.

INTRODUCTION: Assessment of cardiac function is key in the management of intensive care unit (ICU) patients and frequently relies on the use of standard transthoracic echocardiography (TTE). A commercially available new generation ultrasound system with two-dimensional imaging capability, which has roughly the size of a mobile phone, is adequately suited to extend the physical examination. The primary endpoint of this study was to evaluate the additional value of this new miniaturized device used as an ultrasonic stethoscope (US) for the determination of left ventricular (LV) systolic function, when compared to conventional clinical assessment by experienced intensivists. The secondary endpoint was to validate the US against TTE for the semi-quantitative assessment of left ventricular ejection fraction (LVEF) in ICU patients. METHODS: In this single-center prospective descriptive study, LVEF was independently assessed clinically by the attending physician and echocardiographically by two experienced intensivists trained in critical care echocardiography who used the US (size: 135×73×28 mm; weight: 390 g) and TTE. LVEF was visually estimated semi-quantitatively and classified in one of the following categories: increased (LVEF>75%), normal (LVEF: 50 to 75%), moderately reduced (LVEF: 30 to 49%), or severely reduced (LVEF<30%). Biplane LVEF measured using the Simpson's rule on TTE loops by an independent investigator was used as reference. RESULTS: A total of 94 consecutive patients were studied (age: 60±17 years; simplified acute physiologic score 2: 41±15), 63 being mechanically ventilated and 36 receiving vasopressors and/or inotropes. Diagnostic concordance between the clinically estimated LVEF and biplane LVEF was poor (Kappa: 0.33; 95% CI: 0.16 to 0.49) and only slightly improved by the knowledge of a previously determined LVEF value (Kappa: 0.44; 95% CI: 0.22 to 0.66). In contrast, the diagnostic agreement was good between visually assessed LVEF using the US and TTE (Kappa: 0.75; CI 95%: 0.63 to 0.87) and between LVEF assessed on-line and biplane LVEF, regardless of the system used (Kappa: 0.75; CI 95%: 0.64 to 0.87 and Kappa: 0.70; CI 95%: 0.59 to 0.82, respectively). CONCLUSIONS: In ICU patients, the extension of physical examination using an US improves the ability of trained intensivists to determine LVEF at bedside. With trained operators, the semi-quantitative assessment of LVEF using the US is accurate when compared to standard TTE.

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) < or = 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 < or = 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 < or = 1.4, pulmonary vein S/D > 0.65 and systolic fraction > 44% best predicted an invasive PAOP < or = 18 mmHg. Lateral E/E' < or = 8.0 or E/Vp < or = 1.7 predicted a PAOP < or = 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 < or = 18 mmHg in ventilated patients. This further increases its diagnostic value in patients with suspected acute lung injury/acute respiratory distress syndrome.

Quantitative assessment of pleural effusion in critically ill patients by means of ultrasonography.

OBJECTIVE: To assess the ability of ultrasonography to identify the presence and assess the volume of pleural effusion in the intensive care unit setting. DESIGN: Prospective descriptive clinical study. SETTING: Medical-surgical intensive care unit of a teaching hospital. PATIENTS: Initial study group (group I) consisted of 97 patients (mean [+/-SD] Simplified Acute Physiology Score II, 40 +/- 14) with clinically suspected pleural effusion. Fifty-one patients were mechanically ventilated and 55 patients underwent a unilateral or bilateral thoracentesis (58 procedures). All patients underwent supine chest radiography and pleural ultrasonography at bedside. The testing group (group II) consisted of 19 additional patients (17 under ventilation) who underwent thoracentesis. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Maximal interpleural distance was measured at the base and apex of the pleural space, at both end-expiration and end-inspiration. In group I, interpleural distances were compared to actual volume of fluid in the subset of patients who underwent a complete thoracentesis (n = 49). Prediction of the volume of pleural effusion was subsequently tested prospectively in group II (25 complete thoracenteses). Portable chest radiography and pleural ultrasonography yielded discordant results for 47 patients (48%) in the diagnosis of pleural effusion. The expiratory interpleural distance measured at the thoracic base with ultrasonography was significantly correlated with the volume of fluid (p < .0001; coefficient of determination: right, 0.78; left, 0.51). A pleural effusion > or =800 mL was predicted when this distance was >45 mm (right) or >50 mm (left), with a sensitivity of 94% and 100% and a specificity of 76% and 67%, respectively. In group II, the mean bias between the predicted and observed volumes of pleural effusion determined by thoracentesis was 24 +/- 355 mL, and this decreased to 28 +/- 146 mL for the prediction of pleural effusion <1400 mL. CONCLUSIONS: Bedside ultrasonography is well suited for the quantitative assessment of unloculated pleural effusions in intensive care unit patients.

Hemodynamic assessment of critically ill patients using echocardiography Doppler.

PURPOSE OF REVIEW: The evaluation of hemodynamic status in critically ill patients is a leading recommended indication of transesophageal echocardiography in the intensive care unit. Advantages and diagnostic yield of transesophageal echocardiography in this setting are particularly relevant when considering limitations and questioned prognostic impact of pulmonary artery catheterization. RECENT FINDINGS: Recent clinical studies have been performed to validate and assess the value of transesophageal echocardiography in determining cardiac output, cardiac preload dependence, right ventricular function, and left ventricular filling pressure. In addition, diagnostic capacity and therapeutic impact of transesophageal echocardiography have been widely reported in various intensive care unit settings. SUMMARY: Transesophageal echocardiography appears well suited for the determination of cardiac index and to track its variations after therapeutic interventions. Although repeated measurements of left ventricular end-diastolic dimension allows to accurately track preload variations, a single determination is not reliable to predict fluid responsiveness in intensive care unit patients. Identification of preload dependence in hemodynamically unstable patients currently tends to rely mainly on dynamic parameters that use cardiopulmonary interactions under mechanical ventilation. Transesophageal echocardiography also allows to adequately assess right ventricular function and left ventricular filling pressure using combined Doppler modalities. Adequate education and training of intensivists and anesthesiologists is crucial to further develop the use of transesophageal echocardiography in the intensive care unit setting. Despite the absence of randomized controlled studies documenting transesophageal echocardiography benefits on patient outcome, present evidence and experience strongly recommend a larger use of echocardiography Doppler for a comprehensive functional hemodynamic assessment of critically ill patients with circulatory failure.

Hand-held echocardiography with Doppler capability for the assessment of critically-ill patients: is it reliable?

OBJECTIVE: To evaluate the diagnostic capability of a hand-carried ultrasound device (HCU) in critically ill patients when using conventional transthoracic echocardiography (TTE) as a reference. DESIGN: Prospective, descriptive study. SETTING: Medical-surgical intensive care unit of a teaching hospital. PATIENTS: All patients requiring a TTE study were eligible. INTERVENTIONS: Each patient underwent an echocardiographic examination using a full-feature echocardiographic platform (Sonos 5500, Philips Medical Systems, Andover, MA) and a small battery-operated device (SonoHeart Elite, SonoSite, Bothell, WA). The operators (level III training in echocardiography) were randomized (HCU vs. TTE) and they independently interpreted the echocardiograms at the patient bedside. RESULTS: During a 2-month period, 55 consecutive patients (age: 61+/-16 years, simplified acute physiology score 46+/-15, body mass index 26+/-7) were studied, 40 of them being mechanically ventilated (73%). The number of acoustic windows was comparable using HCU and TTE (2.3+/-0.8 vs. 2.4+/-0.8: P=0.24). The overall diagnostic accuracy of HCU was lower compared with conventional TTE (137/171 vs. 158/171 clinical questions solved: P=0.002), reaching 80% and 92%, respectively. Despite its spectral Doppler capability, HCU missed diagnoses that were adequately identified by TTE: elevated left ventricular pressure ( n=2), relevant valvulopathy ( n=2) and moderate ( n=4) or severe ( n=2) pulmonary hypertension. Acute management was altered by HCU and TTE findings in 27 patients (49%) and 28 patients (51%), respectively. CONCLUSIONS: In this study, HCU had a lower diagnostic accuracy compared with conventional TTE, despite its spectral Doppler capability. Further studies are needed to validate these evolving diagnostic tools in critical care settings.

Assessment of Right Ventricular and Right Atrial Systolic and Diastolic Performance Using Automated Border Detection.

Noninvasive assessment of right ventricular (RV) function is important clinically, but current techniques have limitations. Acoustic quantification (AQ) is an automated endocardial border detection technique that allows continuous determination of RV and right atrial (RA) area waveforms and may be useful for the assessment of RA and RV systolic and diastolic performance. Fifty patients (10 normal, 40 with RV pathology) were studied. Signal-averaged RA and RV AQ area waveforms were obtained and analyzed to compute parameters of diastolic and systolic function. All groups demonstrated significant diastolic dysfunction on the RA AQ waveform as manifested by a reduced percentage of passive atrial emptying and increased dependence on active atrial emptying. Abnormalities of diastolic performance were noted in all subgroups on RV AQ analysis as evidenced by a reduction in the percentage of ventricular filling occurring during early diastole and an increased contribution from active atrial contraction. This study demonstrates the feasibility of using automated analysis of signal-averaged RA and RV area waveforms for the evaluation of RV systolic and diastolic performance. This technique identified significant systolic and diastolic dysfunction in four groups of commonly seen right heart pathologies including biventricular heart failure, pulmonary hypertension, pressure and volume overloaded RVs, and biventricular hypertrophy.