Non-invasive oscillometric versus invasive arterial blood pressure measurements in critically ill patients:A post hoc analysis of a prospective observational study

PURPOSE: The aim was to compare non-invasive blood pressure measurements with invasive blood pressure measurements in critically ill patients. METHODS: Non-invasive blood pressure was measured via automated brachial cuff oscillometry, and simultaneously the radial arterial catheter-derived measurement was recorded as part of a prospective observational study. Measurements of systolic arterial pressure (SAP), diastolic arterial pressure (DAP), and mean arterial pressure (MAP) were compared using Bland-Altman and error grid analyses. RESULTS: Paired measurements of blood pressure were available for 736 patients. Observed mean difference (±SD, 95% limits of agreement) between oscillometrically and invasively measured blood pressure was 0.8 mmHg (±15.7 mmHg, -30.2 to 31.7 mmHg) for SAP, -2.9 mmHg (±11.0 mmHg, -24.5 to 18.6 mmHg) for DAP, and -1.0 mmHg (±10.2 mmHg, -21.0 to 18.9 mmHg) for MAP. Error grid analysis showed that the proportions of measurements in risk zones A to E were 78.3%, 20.7%, 1.0%, 0%, and 0.1% for MAP. CONCLUSION: Non-invasive blood pressure measurements using brachial cuff oscillometry showed large limits of agreement compared to invasive measurements in critically ill patients. Error grid analysis showed that measurement differences between oscillometry and the arterial catheter would potentially have triggered at least low-risk treatment decisions in one in five patients

Clinical examination, critical care ultrasonography and outcomes in the critically ill : cohort profile of the Simple Intensive Care Studies-I

Purpose In the Simple Intensive Care Studies-I (SICS-I), we aim to unravel the value of clinical and haemodynamic variables obtained by physical examination and critical care ultrasound (CCUS) that currently guide daily practice in critically ill patients. We intend to (1) measure all available clinical and haemodynamic variables, (2) train novices in obtaining values for advanced variables based on CCUS in the intensive care unit (ICU) and (3) create an infrastructure for a registry with the flexibility of temporarily incorporating specific (haemodynamic) research questions and variables. The overall purpose is to investigate the diagnostic and prognostic value of clinical and haemodynamic variables. Participants The SICS-I includes all patients acutely admitted to the ICU of a tertiary teaching hospital in the Netherlands with an ICU stay expected to last beyond 24 hours. Inclusion started on 27 March 2015. Findings to date On 31 December 2016, 791 eligible patients fulfilled our inclusion criteria of whom 704 were included. So far 11 substudies with additional variables have been designed, of which six were feasible to implement in the basic study, and two are planned and awaiting initiation. All researchers received focused training for obtaining specific CCUS images. An independent Core laboratory judged that 632 patients had CCUS images of sufficient quality. Future plans We intend to optimise the set of variables for assessment of the haemodynamic status of the critically ill patient used for guiding diagnostics, prognosis and interventions. Repeated evaluations of these sets of variables are needed for continuous improvement of the diagnostic and prognostic models. Future plans include: (1) more advanced imaging; (2) repeated clinical and haemodynamic measurements; (3) expansion of the registry to other departments or centres; and (4) exploring possibilities of integration of a randomised clinical trial superimposed on the registry. Study registration number NCT02912624; Pre-results.Peer reviewe

Should the ultrasound probe replace your stethoscope? A SICS-I sub-study comparing lung ultrasound and pulmonary auscultation in the critically ill

BACKGROUND: In critically ill patients, auscultation might be challenging as dorsal lung fields are difficult to reach in supine-positioned patients, and the environment is often noisy. In recent years, clinicians have started to consider lung ultrasound as a useful diagnostic tool for a variety of pulmonary pathologies, including pulmonary edema. The aim of this study was to compare lung ultrasound and pulmonary auscultation for detecting pulmonary edema in critically ill patients. METHODS: This study was a planned sub-study of the Simple Intensive Care Studies-I, a single-center, prospective observational study. All acutely admitted patients who were 18 years and older with an expected ICU stay of at least 24 h were eligible for inclusion. All patients underwent clinical examination combined with lung ultrasound, conducted by researchers not involved in patient care. Clinical examination included auscultation of the bilateral regions for crepitations and rhonchi. Lung ultrasound was conducted according to the Bedside Lung Ultrasound in Emergency protocol. Pulmonary edema was defined as three or more B lines in at least two (bilateral) scan sites. An agreement was described by using the Cohen κ coefficient, sensitivity, specificity, negative predictive value, positive predictive value, and overall accuracy. Subgroup analysis were performed in patients who were not mechanically ventilated. RESULTS: The Simple Intensive Care Studies-I cohort included 1075 patients, of whom 926 (86%) were eligible for inclusion in this analysis. Three hundred seven of the 926 patients (33%) fulfilled the criteria for pulmonary edema on lung ultrasound. In 156 (51%) of these patients, auscultation was normal. A total of 302 patients (32%) had audible crepitations or rhonchi upon auscultation. From 130 patients with crepitations, 86 patients (66%) had pulmonary edema on lung ultrasound, and from 209 patients with rhonchi, 96 patients (46%) had pulmonary edema on lung ultrasound. The agreement between auscultation findings and lung ultrasound diagnosis was poor (κ statistic 0.25). Subgroup analysis showed that the diagnostic accuracy of auscultation was better in non-ventilated than in ventilated patients. CONCLUSION: The agreement between lung ultrasound and auscultation is poor

Making energy efficiency pro-poor : insights from behavioural economics for policy design

This paper reviews the current state of behavioural economics and its applications to energy efficiency in developing countries. Taking energy efficient lighting in Ghana, Uganda and Rwanda as empirical examples, this paper develops hypotheses on how behavioural factors can improve energy efficiency policies directed towards poor populations. The key argument is that different types of affordability exist that are influenced by behavioural factors to varying degrees. Using a qualitative approach, this paper finds that social preferences, framing and innovative financing solutions that acknowledge people’s mental accounts can provide useful starting points. Behavioural levers are only likely to work in a policy package that addresses wider technical, market and institutional barriers to energy efficiency. More research, carefully designed pre-tests and stakeholder debates are required before introducing policies based on behavioural insights. This is imperative to avoid the dangers of nudging

Clinical, biochemical and haemodynamic variables as independent predictors of 90-day mortality:The Simple Intensive Care Studies-I

INTRODUCTION. Clinical, biochemical and haemodynamic variables are used to diagnose circulatory shock and guide treatment in the critically ill. Literature is inconsistent which clinical signs have the best prognostic value on top of well-validated prognostic scores such as the simplified acute physiology score (SAPS II). OBJECTIVES. The objective of the Simple Intensive Care Studies-I (SICS-I: NCT02912624) was to evaluate the association of clinical, biochemical and haemodynamic variables with 90-day mortality in a large, consecutive, cohort of critically ill patients [1]. METHODS. This prospective cohort study included all consecutive adults who were acutely admitted with an intensive care unit (ICU) stay expected to last beyond 24 hours. We conducted a protocolised clinical examination and critical care ultrasonography (CCUS) within 24 hours of ICU admission. Our primary outcome was 90-day mortality. Our secondary outcomes were 7-and 30-day mortality, and 90-day mortality by type of circulatory shock and clinical subgroups. We used multivariable Cox regression analyses to identify independent predictors of mortality. RESULTS. From 27 March 2015 until 22 July 2017, 1104 patients were included. A total of 298 patients (28%) died at 90-day follow-up. Patients who died were older, more often ventilated, unconscious and dependent on noradrenalin, had lower blood pressures and urine output, and more often had an impaired microcirculation (tables 1-3). Multivariable Cox regression adjusted for age and SAPS-II score showed that respiratory rate (HR 1.02; 95% CI 1.00-1.04), unrespon-siveness (HR 1.53; 95% CI 1.08-2.16) and serum lactate (HR 1.08; 95% CI 1.03-1.13) were independently associated with 90-day mortality. In patients with septic shock independent predictors were mottling rate (HR 1.27; 95% CI 1.02-1.58) and serum lactate (HR 1.11; 95% CI 1.02-1.22), whereas diuresis <0.5 ml/kg/h (HR 2.27; 95% CI 1.00-5.15) and a mean arterial pressure <70 mmHg despite vasopressor treatment (HR 5.08; 95% CI 2.00-12.9) were independent predictors in patients with heart failure. CONCLUSIONS. Simple clinical variables as respiratory rate, consciousness, and serum lactate are independently associated with 90-day mortality in a large, unselected cohort of critically ill patients. The predictive value of clinical signs changed in clinical subgroups. Skin mottling and lactate showed the strongest associations in patients with septic shock and impaired diuresis and low mean arterial pressures were independently associated with 90-day mortality in patients with heart failure. [Table Presented]

Clinical examination for diagnosing circulatory shock: The Simple Intensive Care Studies-I

INTRODUCTION. The latest consensus on circulatory shock advocates clinical examination and ultrasonography for diagnosing circulatory shock. Propagation of daily clinical examination contrasts with available studies, which are of limited quality and quantity so that its level of evidence is considered 'best practice'. We hypothesize that clinical estimation of circulatory shock, should be based on multiple variables including combinations of clinical, laboratory and ultrasonography variables. OBJECTIVES. To evaluate the value of clinical examination, biochemical and ultrasonography variables in the critically ill, specifically for estimation which combinations of variables are associated with cardiac output. METHODS. We initiated the Simple Intensive Care Studies-I (SICS-I) which was designed as a prospective cohort study to include all patients acutely admitted to the intensive care unit. Clinical examination was performed in a standardized fashion in all patients according to predefined criteria including variables of heart rate, blood pressures, central venous pressure, mental state, auscultation of heart and lungs, respiratory rate, urine output, capillary refill times, central to peripheral temperatures gradients, skin mottling; biochemical variables including lactate; and ultrasonography of heart and lungs. These clinical, biochemical, and ultrasonography variables were recorded following a published protocol (NCT02912624). Circulatory shock was defined by the requirement of vasopressors and/or inotropes and measured by cardiac output using transthoracic ultrasonography. All researchers, including medical students, underwent focused training for recording of all variables, including obtaining specific ultrasonography images. Cardiac function was clinically estimated as well before being measured by ultrasonography. RESULTS. Between March 2015 and December 2016 a total of 704 out of 791 eligible patients were included. An independent Core laboratory assessed that ultrasonography images from 632 patients (90%) were of sufficient quality. Vasopressors and/or inotropes were used upon admission in 363 cases (52%). 173 patients (25%) had died at 90-day follow-up. The data of all patients included until July 1st, 2017 will be analysed to identify combinations of variables independently associated with cardiac output. At the congress, these results will be presented and these variables will inform the second phase of the on-going registry. CONCLUSIONS. Standardized clinical examination and ultrasonography in critically ill patients by novices is feasible. We will be able to answer whether clinical assessment of the presence of shock can reliably be established and if so, which combinations of variables are most informative for estimation of the patients' cardiac output

Identifying and characterizing high-risk clusters in a heterogeneous ICU population with deep embedded clustering

Critically ill patients constitute a highly heterogeneous population, with seemingly distinct patients having similar outcomes, and patients with the same admission diagnosis having opposite clinical trajectories. We aimed to develop a machine learning methodology that identifies and provides better characterization of patient clusters at high risk of mortality and kidney injury. We analysed prospectively collected data including co-morbidities, clinical examination, and laboratory parameters from a minimally-selected population of 743 patients admitted to the ICU of a Dutch hospital between 2015 and 2017. We compared four clustering methodologies and trained a classifier to predict and validate cluster membership. The contribution of different variables to the predicted cluster membership was assessed using SHapley Additive exPlanations values. We found that deep embedded clustering yielded better results compared to the traditional clustering algorithms. The best cluster configuration was achieved for 6 clusters. All clusters were clinically recognizable, and differed in in-ICU, 30-day, and 90-day mortality, as well as incidence of acute kidney injury. We identified two high mortality risk clusters with at least 60%, 40%, and 30% increased. ICU, 30-day and 90-day mortality, and a low risk cluster with 25–56% lower mortality risk. This machine learning methodology combining deep embedded clustering and variable importance analysis, which we made publicly available, is a possible solution to challenges previously encountered by clustering analyses in heterogeneous patient populations and may help improve the characterization of risk groups in critical care

Chronic Metformin Treatment is Associated with Reduced Myocardial Infarct Size in Diabetic Patients with ST-segment Elevation Myocardial Infarction

Increased myocardial infarct (MI) size is associated with higher risk of developing left ventricular dysfunction, heart failure and mortality. Experimental studies have suggested that metformin treatment reduces MI size after induced ischaemia but human data is lacking. We aimed to investigate the effect of metformin on MI size in patients presenting with an acute MI. All consecutive patients (n = 3,288) presenting to our hospital with ST-segment elevation myocardial infarction (STEMI) undergoing primary PCI between January 2004 and December 2010 were included in this retrospective analysis. Patients with diabetes were divided according to metformin versus non-metformin based pharmacotherapy. MI size was estimated using peak values of serum creatine kinase (CK), myocardial band of CK (CK-MB), and troponin-T. We identified 677 (20.6 %) patients with diabetes, of whom 189 (27.9 %) were treated with metformin. Chronic metformin treatment was associated with lower peak levels of CK (1,101 vs. 1,422 U/L, P = 0.005), CK-MB (152 vs. 182 U/L, P = 0.018) and troponin-T (2.5 vs. 4.0 ng/L, P = 0.021) compared to non-metformin using diabetics. After adjustment for age, sex, TIMI flow post PCI, and previous MI, the use of metformin treatment remained an independent predictor of smaller MI size. Patient with diabetes treated with metformin had even smaller MI size than patients without diabetes. Chronic metformin treatment is associated with reduced MI size compared to non-metformin based strategies in diabetic patients presenting with STEMI. Metformin might have additional beneficial effects beyond glucose lowering efficacy