Basic echocardiography competence program in intensive care units: A multinational survey of intensive care units accredited by the College of Intensive Care Medicine.

In 2014, basic critical care echocardiography (BCCE) competence became a mandatory requirement for trainees registered with the College of Intensive Care Medicine (CICM). To determine the proportion of CICM intensive care units (ICUs) that conduct a BCCE competence program and to learn about the barriers/challenges and successful strategies, we conducted a survey of intensivists working in ICUs accredited by CICM for basic/advanced training in Australia, New Zealand, Hong Kong, Singapore, Ireland and India. Following consultations with content experts and a trial phase to improve clarity and minimise ambiguity, an 11-point questionnaire survey was sent to one intensivist from every CICM-accredited ICU by several methods. Participation was voluntary. Consent was implied. No incentives were offered. Results are reported as numbers and percentages. Of the 104 ICUs surveyed, 99 (95.1%) responded, with 75 (75.8%) having no BCCE teaching whatsoever. In the remaining 24 (24.2%) ICUs, the teaching process was widely variable. Only 5/99 (5.1%) ICUs provided a structured BCCE competence program through which trainees performed and archived BCCE scans, maintained a logbook and underwent formative and summative assessments for credentialling. Six more ICUs provided formative assessment but relied on external bodies for competence assessment. Overall, 20/99 (20.2%) ICUs allowed trainees to perform unsupervised scans for clinical management, even if they were not BCCE competent. Nineteen intensivists perceived management errors due to misinterpretation of echocardiographic findings. Very few CICM-accredited ICUs offer a structured BCCE competence program. To fulfil the objective of universal BCCE competence, potential solutions are presented.

The comparative effects of 3% saline and 0.5M sodium lactate on cardiac function:a randomised, crossover study in volunteers.

OBJECTIVE: To investigate the metabolic and cardiac effects of intravenous administration of two hypertonic solutions - 3% saline (SAL) and 0.5M sodium lactate (LAC). DESIGN, SETTING AND PARTICIPANTS: A randomised, doubleblind, crossover study in ten human volunteers. Intravenous bolus of either SAL or LAC at 3 mL/kg over 20 min followed by a 2 mL/kg infusion over 60 min. MAIN OUTCOME MEASURES: Acid base parameters and echocardiographic indices of cardiac function, cardiac output (CO), left ventricular ejection fraction (LVEF) and mitral annular peak systolic velocity (Sm) before and after infusion of SAL or LAC. RESULTS: Despite haemodilution, we observed an increase in sodium (139 ± 2 mmol/L to 142 ± 2 mmol/L in both groups) and respective anions, chloride (106 ± 2 mmol/L to 112 ± 3 mmol/L) and lactate (1.01 ± 0.28 mmol/L to 2.38 ± 0.38 mmol/L) with SAL and LAC, respectively. The pH (7.37 ± 0.03 to 7.45 ± 0.03; P < 0.01) and simplified strong ion difference (SID) (36.3 ± 4.6 mmol/L to 39.2 ± 3.6 mmol/L; P < 0.01) increased during the LAC infusion. The pH was unchanged, but SID decreased during SAL infusion (36.3 ± 2.5 mmol/L to 33.9 ± 3.1 mmol/L; P = 0.01). Both solutions led to an increase in preload and cardiac function, CO (4.36 ± 0.79 L/min to 4.98 ± 1.37 L/ min v 4.62 ± 1.30 L/min to 5.13 ± 1.44 L/min), LVEF (61 ± 6% to 63 ± 8% v 64 ± 6% to 68 ± 7%). The averaged Sm improved in the LAC group as compared with the SAL group (0.088 ± 0.008 to 0.096 ± 0.016 v 0.086 ± 0.012 to 0.082 ± 0.012; P = 0.032). CONCLUSIONS: The administration of SAL or LAC has opposing effects on acid base variables such as SID. Hypertonic fluid infusion lead to increased cardiac preload and performance with Sm, suggesting better left ventricular systolic function during LAC as compared with SAL. Lactated hypertonic solutions should be evaluated as resuscitation fluids.

Longitudinal wall fractional shortening: an M-mode index based on mitral annular plane systolic excursion (MAPSE) that correlates and predicts left ventricular longitudinal strain (LVLS) in intensive care patients.

BACKGROUND: Left ventricular longitudinal strain (LVLS) is a modern measurement for LV function. However, strain measurement is often difficult in critically ill patients. We sought to show LVLS can be estimated using M-mode-derived longitudinal wall fractional shortening (LWFS), which is less dependent on image quality and is easier to perform in critically ill patients. METHODS: Transthoracic echocardiographic records were retrospectively screened and 80 studies suitable for strain and M-mode measurements in the apical 4-chamber view were selected. Longitudinal wall fractional shortening was derived from conventional M-mode (LWFS) and curved anatomical M-mode (CAMMFS). The relationships between LVLS and mitral annular plane systolic excusion (MAPSE) and M-mode-derived fractional shortening were examined using univariate generalized linear model in a training set (n = 50) and was validated in a separate validation set (n = 30). RESULTS: MAPSE, CAMMFS, and LWFS demonstrated very good correlations with LVLS (r = 0.852, 0.875 and 0.909, respectively). LWFS was the best unbiased predictor for LVLS (LVLS = 1.180 x LWFS - 0.737, P < 0.001). Intra- and inter-rater agreement and reliability for LWFS measurement were good. CONCLUSIONS: LVLS can be estimated by LWFS in the critically ill patients. It provides a fast and accurate prediction of LVLS. LWFS is a reproducible and reliable measurement which can be used as a potential index in place of LVLS in the critically ill population.

Hypoxia enhances the viability, growth and chondrogenic potential of cryopreserved human adipose-derived stem cells.

Cryopreservation is the only existing method of storage of human adipose-derived stem cells (ASCs) for clinical use. However, cryopreservation has been shown to be detrimental to ASCs, particularly in term of cell viability. To restore the viability of cryopreserved ASCs, it is proposed to culture the cells in a hypoxic condition. To this end, we aim to investigate the effect of hypoxia on the cryopreserved human ASCs in terms of not only cell viability, but also their growth and stemness properties, which have not been explored yet. In this study, human ASCs were cultured under four different conditions: fresh (non-cryopreserved) cells cultured in 1) normoxia (21% O2) and 2) hypoxia (2% O2) and cryopreserved cells cultured in 3) normoxia and 4) hypoxia. ASCs at passage 3 were subjected to assessment of viability, proliferation, differentiation, and expression of stemness markers and hypoxia-inducible factor-1 alpha (HIF-1α). We found that hypoxia enhances the viability and the proliferation rate of cryopreserved ASCs. Further, hypoxia upregulates HIF-1α in cryopreserved ASCs, which in turn activates chondrogenic genes to promote chondrogenic differentiation. In conclusion, hypoxic-preconditioned cryopreserved ASCs could be an ideal cell source for cartilage repair and regeneration.

Half-molar sodium lactate infusion improves cardiac performance in acute heart failure: a pilot randomised controlled clinical trial.

INTRODUCTION: Acute heart failure (AHF) is characterized by inadequate cardiac output (CO), congestive symptoms, poor peripheral perfusion and end-organ dysfunction. Treatment often includes a combination of diuretics, oxygen, positive pressure ventilation, inotropes and vasodilators or vasopressors. Lactate is a marker of illness severity but is also an important metabolic substrate for the myocardium at rest and during stress. We tested the effects of half-molar sodium lactate infusion on cardiac performance in AHF. METHODS: We conducted a prospective, randomised, controlled, open-label, pilot clinical trial in 40 patients fulfilling two of the following three criteria for AHF: (1) left ventricular ejection fraction <40%, (2) acute pulmonary oedema or respiratory failure of predominantly cardiac origin requiring mechanical ventilation and (3) currently receiving vasopressor and/or inotropic support. Patients in the intervention group received a 3 ml/kg bolus of half-molar sodium lactate over the course of 15 minutes followed by 1 ml/kg/h continuous infusion for 24 hours. The control group received only a 3 ml/kg bolus of Hartmann's solution without continuous infusion. The primary outcome was CO assessed by transthoracic echocardiography 24 hours after randomisation. Secondary outcomes included a measure of right ventricular systolic function (tricuspid annular plane systolic excursion (TAPSE)), acid-base balance, electrolyte and organ function parameters, along with length of stay and mortality. RESULTS: The infusion of half-molar sodium lactate increased (mean ± SD) CO from 4.05 ± 1.37 L/min to 5.49 ± 1.9 L/min (P < 0.01) and TAPSE from 14.7 ± 5.5 mm to 18.3 ± 7 mm (P = 0.02). Plasma sodium and pH increased (136 ± 4 to 146 ± 6 and 7.40 ± 0.06 to 7.53 ± 0.03, respectively; both P < 0.01), but potassium, chloride and phosphate levels decreased. There were no significant differences in the need for vasoactive therapy, respiratory support, renal or liver function tests, duration of ICU and hospital stay or 28- and 90-day mortality. CONCLUSIONS: Infusion of half-molar sodium lactate improved cardiac performance and led to metabolic alkalosis in AHF patients without any detrimental effects on organ function. TRIAL REGISTRATION: Clinicaltrials.gov NCT01981655. Registered 13 August 2013.

The use of the right ventricular diameter and tricuspid annular tissue Doppler velocity parameter to predict the presence of pulmonary hypertension.

AIMS: Detecting the presence of pulmonary hypertension (PH) is important especially with unexplained dyspnoea and suspected thromboembolism. Although PH can be detected invasively by right ventricular (RV) catheterisation, accurate non-invasive assessment by echocardiography has many advantages. This however relies on the presence of tricuspid regurgitation (TR). We examined if the presence of PH can be predicted echocardiographically without relying on TR. METHODS AND RESULTS: Seventy-six consecutive patients with TR were recruited, and another 32 were used for prediction study. RV end-diastolic diameter (RVD) was measured in the apical view and tissue Doppler imaging (TDI) parameters were obtained from the lateral tricuspid annulus motion. Pulmonary artery systolic pressures (PASP) were estimated from TR. The RVD, and the TDI duration from start of isovolumic contraction to peak systole, T(peak), correlated with PASP. However, the RVD/T(peak) ratio offered the best correlation and, at a cutoff of 22 cm/s, predicted the presence of PH with 80% sensitivity and 83% specificity. The same results were obtained even if the study was confined to patients with or without RV dysfunction. The ratio displayed a good correlation with catheter-derived PASP in nine separate patients. CONCLUSION: While RVD and T(peak) can adequately detect the presence of PH, RVD/T(peak) acted as the best predictor for PH. The results apply regardless of the presence or absence of RV dysfunction.

A modified postural drainage position produces less cardiovascular stress than a head-down position in patients with severe heart disease: a quasi-experimental study.

QUESTION: Does a modified postural drainage position (horizontal) produce less cardiovascular and respiratory stress than a head-down postural drainage position (30 degrees) in people with severe heart disease? DESIGN: A quasi-experimental study. PARTICIPANTS: Thirty-one patients (mean age 69 years, SD 13) with severe left ventricular systolic dysfunction (mean ejection fraction 23%, SD 7) who were stable, receiving regular medication and free of acute respiratory illness. INTERVENTION: Two manoeuvres were performed--one from long sitting to a modified (horizontal) postural drainage position, and one from long sitting to a head-down (30 degrees) postural drainage position. OUTCOME MEASURES: Cardiovascular responses examined were blood pressure, sphygmocardiographic indices, and cardiac rhythm. Respiratory responses examined were respiratory rate, transcutaneous arterial oxyyhaemoglobin saturation, and dyspnoea. RESULTS: Three participants were intolerant to the postural drainage positions--two during head-down and one during modified positioning. The remaining 28 participants maintained their resting cardiac rhythm and did not complain of chest pain or dyspnoea. The changes in cardiovascular responses during the sitting to head-down postural drainage manoeuvre in the tolerant participants were significantly greater (p < 0.05) than the changes during the sitting to the modified postural drainage manoeuvre for most of the sphygmocardiographic indices. In contrast, there were no significant respiratory responses to either postural drainage manoeuvre. CONCLUSION: Modified positioning is associated with less cardiovascular stress than head-down positioning, yet for most patients with severe heart disease, both positions are generally well tolerated. For a subset of these patients, either position may be inappropriate. This suggests that modified positioning should be attempted first but that a head-down position may be attempted if the modified position proves ineffective.

Duration of the beneficial effects of levosimendan in decompensated heart failure as measured by echocardiographic indices and B-type natriuretic peptide.

Levosimendan is effective in the treatment of decompensated heart failure. The beneficial effects of a single dose of levosimendan last much longer than those of other inotropes. However, the exact duration of the beneficial effects is unknown. We prospectively determined the duration of the cardiac effects, as measured by echocardiography, of levosimendan (LS) following a 24-hour infusion regimen in patients with decompensated heart failure (DHF). The effects of LS on plasma B-type natriuretic peptide (BNP) were also examined. Twenty patients with DHF displaying (1) deteriorating symptoms despite optimal oral therapy, (2) left ventricular ejection fractions (LVEF) < 35%, and (3) cardiac indices of < 2.5 L/m/min received 24 hours of LS infusion. Echocardiography and BNP measurements were performed pre- and postinfusion and were reassessed on days 7, 30, and 90. Left ventricular systolic function indices (cardiac output and LVEF), LV filling pressure indices, and right ventricular systolic function indices all improved following LS treatment. Most of these improvements were sustained for at least 7 days (P < 0.05) and returned to baseline by day 30 postinfusion and remained so on day 90. Plasma BNP also displayed the same pattern of transient improvements. In conclusion, LS transiently improved the cardiac function, and the effects lasted for at least 7 days after discontinuation of infusion. Most effects, except LVEF, were not significantly different from baseline on day 30.

Diagnoses of right-sided empyema complicating tricuspid valve endocarditis during transesophageal echocardiography.

A 25-year-old man, who was a known intravenous drug user, underwent transesophageal echocardiography as part of investigation for suggested infective endocarditis. Tricuspid valve infective endocarditis was diagnosed. The simultaneous visualization of right-sided empyema, previously undiagnosed, by transesophageal echocardiography, led to operative treatment by thoracoscopy and right lung decortication.