Explore the vast range of titles available.

Intensive-care clinicians are presented with large quantities of measurements from multiple monitoring systems. The limited ability of humans to process complex information hinders early recognition of patient deterioration, and high numbers of monitoring alarms lead to alarm fatigue. We used machine learning to develop an early-warning system that integrates measurements from multiple organ systems using a high-resolution database with 240 patient-years of data. It predicts 90% of circulatory-failure events in the test set, with 82% identified more than 2 h in advance, resulting in an area under the receiver operating characteristic curve of 0.94 and an area under the precision-recall curve of 0.63. On average, the system raises 0.05 alarms per patient and hour. The model was externally validated in an independent patient cohort. Our model provides early identification of patients at risk for circulatory failure with a much lower false-alarm rate than conventional threshold-based systems. A machine-learning algorithm based on an array of demographic, physiological and clinical information is able to predict, hours in advance, circulatory failure of patients in the intensive-care unit.

Background Septic shock is associated with decreased vasopressor responsiveness. Experimental data suggest that central alpha2-agonists like dexmedetomidine (DEX) increase vasopressor responsiveness and reduce catecholamine requirements in septic shock. However, DEX may also cause hypotension and bradycardia. Thus, it remains unclear whether DEX is hemodynamically safe or helpful in this setting. Methods In this post hoc subgroup analysis of the Sedation Practice in Intensive Care Evaluation (SPICE III) trial, an international randomized trial comparing early sedation with dexmedetomidine to usual care in critically patients receiving mechanical ventilation, we studied patients with septic shock admitted to two tertiary ICUs in Australia and Switzerland. The primary outcome was vasopressor requirements in the first 48 h after randomization, expressed as noradrenaline equivalent dose (NEq [μg/kg/min] = noradrenaline + adrenaline + vasopressin/0.4). Results Between November 2013 and February 2018, 417 patients were recruited into the SPICE III trial at both sites. Eighty-three patients with septic shock were included in this subgroup analysis. Of these, 44 (53%) received DEX and 39 (47%) usual care. Vasopressor requirements in the first 48 h were similar between the two groups. Median NEq dose was 0.03 [0.01, 0.07] μg/kg/min in the DEX group and 0.04 [0.01, 0.16] μg/kg/min in the usual care group ( p  = 0.17). However, patients in the DEX group had a lower NEq/MAP ratio, indicating lower vasopressor requirements to maintain the target MAP. Moreover, on adjusted multivariable analysis, higher dexmedetomidine dose was associated with a lower NEq/MAP ratio. Conclusions In critically ill patients with septic shock, patients in the DEX group received similar vasopressor doses in the first 48 h compared to the usual care group. On multivariable adjusted analysis, dexmedetomidine appeared to be associated with lower vasopressor requirements to maintain the target MAP. Trial registration The SPICE III trial was registered at ClinicalTrials.gov ( NCT01728558 ).

Reduced cellular ATP synthesis due to impaired mitochondrial function of immune cells may be a factor influencing the immune response in septic shock. We investigate changes in mitochondrial function and bioenergetics of human monocytes and lymphocyte subsets. Thirty patients with septic shock were studied at ICU admission, after 24 and 48 hours, and after resolution of shock. Enzymatic activities of citrate synthase and mitochondrial complexes I, IV, and ATP synthase and ATP content of monocytes, T-cells and B-cells and pro-inflammatory (IL-1β and IL-6) and anti-inflammatory (IL-10) cytokine plasma concentrations were compared to samples from 20 healthy volunteers. Large variations in mitochondrial enzymatic activities of immune cells of septic patients were detected. In monocytes, maximum levels of citrate synthase activity in sepsis were significantly lower when compared to controls (p = 0.021). Maximum relative enzymatic activity (ratio relative to citrate synthase activity) of complex I (p<0.001), complex IV (p = 0.017) and ATP synthase (p<0.001) were significantly higher. In T-cells, maximum levels of citrate synthase (p = 0.583) and relative complex IV (p = 0.602) activity did not differ between patients and controls, whereas levels of relative complex I (p = 0.006) and ATP synthase (p = 0.032) were significantly higher in septic patients. In B-cells of patients, maximum levels of citrate synthase activity (p = 0.004) and relative complex I (p<0.001) were significantly higher, and mean levels of relative complex IV (p = 0.042) lower than the control values, whereas relative ATP synthase activity did not differ (p = 1.0). No significant difference in cellular ATP content was detected in any cell line (p = 0.142-0.519). No significant correlations between specific cytokines and parameters of mitochondrial enzymatic activities or ATP content were observed. Significant changes of mitochondrial enzymatic activities occur in human peripheral blood immune cells in septic shock when compared to healthy controls. Assessed sub-types of immune cells showed differing patterns of regulation. Total ATP-content of human immune cells did not differ between patients in septic shock and healthy volunteers.

Subarachnoid hemorrhage (SAH) is a serious condition, and a myocardial injury or dysfunction could contribute to the outcome. We assessed the prevalence and prognostic impact of cardiac involvement in a cohort with SAH. This is a prospective observational multicenter study. We included 192 patients treated for non-traumatic subarachnoid hemorrhage. We performed ECG recordings, echocardiographic examinations, and blood sampling within 24 h of admission and on days 3 and 7 and at 90 days. The primary endpoint was the evidence of cardiac involvement at 90 days, and the secondary endpoint was to examine the prevalence of a myocardial injury or dysfunction. The median age was 54.5 (interquartile range [IQR] 48.0–64.0) years, 44.3% were male and the median World Federation of Neurological Surgeons (WFNS) score was 2 (IQR 1–4). At day 90, 22/125 patients (17.6%) had left ventricular ejection fractions ≤ 50%, and 2/121 patients (1.7%) had evidence of a diastolic dysfunction as defined by mitral peak E-wave velocity by peak eʹ velocity (E/eʹ) > 14. There was no prognostic impact from echocardiographic evidence of cardiac complications on neurological outcomes. The overall prevalence of cardiac dysfunction was modest. We found no demographic or SAH-related factors associated with 90 days cardiac dysfunction.

Ventilator-associated pneumonia (VAP) is a frequent complication of mechanical ventilation and is associated with substantial morbidity and mortality. Accurate diagnosis of VAP relies in part on subjective diagnostic criteria. Surveillance according to ventilator-associated event (VAE) criteria may allow quick and objective benchmarking. Our objective was to create an automated surveillance tool for VAE tiers I and II on a large data collection, evaluate its diagnostic accuracy and retrospectively determine the yearly baseline VAE incidence. We included all consecutive intensive care unit admissions of patients with mechanical ventilation at Bern University Hospital, a tertiary referral center, from January 2008 to July 2016. Data was automatically extracted from the patient data management system and automatically processed. We created and implemented an application able to automatically analyze respiratory and relevant medication data according to the Centers for Disease Control protocol for VAE-surveillance. In a subset of patients, we compared the accuracy of automated VAE surveillance according to CDC criteria to a gold standard (a composite of automated and manual evaluation with mediation for discrepancies) and evaluated the evolution of the baseline incidence. The study included 22′442 ventilated admissions with a total of 37′221 ventilator days. 592 ventilator-associated events (tier I) occurred; of these 194 (34%) were of potentially infectious origin (tier II). In our validation sample, automated surveillance had a sensitivity of 98% and specificity of 100% in detecting VAE compared to the gold standard. The yearly VAE incidence rate ranged from 10.1–22.1 per 1000 device days and trend showed a decrease in the yearly incidence rate ratio of 0.96 (95% CI, 0.93–1.00, p = 0.03). This study demonstrated that automated VAE detection is feasible, accurate and reliable and may be applied on a large, retrospective sample and provided insight into long-term institutional VAE incidences. The surveillance tool can be extended to other centres and provides VAE incidences for performing quality control and intervention studies.

Quantitative data on ventilation during acclimatization at very high altitude are scant. Therefore, we monitored nocturnal ventilation and oxygen saturation in mountaineers ascending Mt. Muztagh Ata (7,546 m). To investigate whether periodic breathing persists during prolonged stay at very high altitude. A total of 34 mountaineers (median age, 46 yr; 7 women) climbed from 3,750 m within 19-20 days to the summit at 7,546 m. During ascent, repeated nocturnal recordings of calibrated respiratory inductive plethysmography, pulse oximetry, and scores of acute mountain sickness were obtained. Nocturnal oxygen saturation decreased, whereas minute ventilation and the number of periodic breathing cycles increased with increasing altitude. At the highest camp (6,850 m), median nocturnal oxygen saturation, minute ventilation, and the number of periodic breathing cycles were 64%, 11.3 L/min, and 132.3 cycles/h. Repeated recordings within 5-8 days at 4,497 m and 5,533 m, respectively, revealed increased oxygen saturation, but no decrease in periodic breathing. The number of periodic breathing cycles was positively correlated with days of acclimatization, even when controlled for altitude, oxygen saturation, and other potential confounders, whereas symptoms of acute mountain sickness had no independent effect on periodic breathing. Our field study provides novel data on nocturnal oxygen saturation, breathing patterns, and ventilation at very high altitude. It demonstrates that periodic breathing increases during acclimatization over 2 weeks at altitudes greater than 3,730 m, despite improved oxygen saturation consistent with a progressive increase in loop gain of the respiratory control system. Clinical trial registered with www.clinicaltrials.gov (NCT00514826).

Background The aim of the study was to evaluate the composition and the temporal evolution of the oropharyngeal microbiome in antibiotic-naïve patients requiring mechanical ventilation and to gain new insights into the pathogenesis of ventilator-associated pneumonia (VAP). Methods Prospective, observational single-center nested case-control study. Patients with acute critical illness and anticipated duration of mechanical ventilation > 4 days were eligible. We took oropharyngeal swabs (and if available, tracheal secretions) daily, starting at the day of intubation. The microbiota was characterized by 16S rRNA high-throughput sequencing and compared between patients developing VAP versus controls. Results Five patients developed VAP. In three patient the causative pathogens were Enterobacteriaceae and in two Haemophilus influenzae . Locally weighted polynomial regression suggested that the within diversity (=alpha) was lower in Enterobacteriaceae VAP patients between days two to five of mechanical ventilation when compared to controls. Detection of Enterobacteriaceae in the oropharynx occurred on day two of follow-up and consisted of a single operational taxonomic unit in 2/3 patients with enterobacterial VAP. Conclusions In acutely-ill patients who developed enterobacterial VAP the causative pathogen gained access to the oropharynx early after starting mechanical ventilation and outgrew the commensal members of the microbiome. Whether a specific pattern of the oropharyngeal microbiome between days three to five of mechanical ventilation may predict VAP enterobacterial VAP has to be evaluated in further studies.

Thoracic ultrasound (TUS) has been successfully used in the diagnosis of community-acquired pneumonia. Little is known about its diagnostic potential in ventilator-associated pneumonia (VAP). The purpose of this study was to systematically describe the morphology and temporal changes of sonographic patterns in mechanically ventilated patients and to evaluate the diagnostic performance characteristics of TUS-based VAP diagnoses. Patients who were placed on invasive ventilation for reasons other than pneumonia and who were considered at risk for the development of VAP received daily TUS examinations while being closely monitored for the development of pneumonia. Fifty-seven patients were studied. The incidence of VAP was 21.1%. Sonographic patterns of reduced or absent lung aeration were found in 64.2% of examinations. The sonographic pattern of lung consolidation with either dynamic or static air bronchograms was 100% sensitive and 60% specific for VAP in those patients who developed clinical signs and symptoms compatible with pneumonia. The pretest and posttest probabilities were 0.38 and 0.6, respectively. Sonographic patterns of abnormal aeration are frequently observed in mechanically ventilated patients. If sonographic lung consolidation with either static or dynamic air bronchograms is absent, VAP is highly unlikely. The presence of these sonographic patterns in patients with signs and symptoms suggestive of pneumonia significantly increases the probability of VAP.

Background Hemodynamic instability is one of the leading causes of intensive care unit (ICU) admission. Early stabilization of hemodynamics is associated with improved outcome. The monitoring used to guide hemodynamic support may influence the time needed to achieve stable hemodynamics. Visualization of the heart using echocardiography offers the advantage of direct measurement of cardiac volumes and ventricular function. A miniaturized monoplane transesophageal echocardiography (TEE) probe was developed, allowing for almost continuous qualitative hemodynamic TEE assessment (hTEE) after brief bedside training. The primary objective of the study is to assess whether hemodynamic monitoring using the hTEE technology shortens time to resolution of shock in ICU patients in comparison to standard monitoring using a central venous catheter, pulmonary artery catheter, or conventional echocardiography. Methods Five hundred consecutive subjects with circulatory shock (low mean arterial blood pressure (MAP) and signs of organ hypoperfusion) at the time of ICU admission are included in the study. The subjects are randomly assigned to one of four groups using a 2 × 2 factorial design stratified by method of hemodynamic monitoring (hTEE vs standard hemodynamic monitoring) and frequency of hemodynamic assessments (minimum every 4 h vs standard of care). The primary study outcome is the time from study inclusion to resolution of circulatory shock, defined as MAP >  60 mmHg for ≥ 4 h after discontinuation of vasopressors and inotropes. The hTEE monitoring consists of the acquisition of three defined echocardiography views: Transgastric mid-esophageal short axis with measurement of fractional area change of left ventricle, mid-esophageal four-chamber view with measurement of the ratio of right to left ventricular area, and mid-esophageal ascending aortic short-axis view with measurement of the superior vena cava collapsibility index. In the control groups, monitoring modalities, including conventional TTE and TEE but not hTEE, are at the discretion of the treating physician. The interpretation of hemodynamic monitoring and the subsequent changes in patient management are recorded after each hemodynamic assessment. Differences in the primary and further secondary time-to-event outcomes will be assessed using a competing risk model accounting for the competing risk of death. Discussion The effect of using echocardiography as a monitoring modality on relevant patient outcomes has not been established so far. The study at hand may be one of the first trials to provide detailed data on effectiveness and safety of echocardiography to guide treatment in patients with circulatory shock. Trial registration ClinicalTrials.gov, ID: NCT02048566. Registered on January 29, 2014.