Using heart-lung interactions to assess fluid responsiveness during mechanical ventilation

According to the Frank-Starling relationship, a patient is a 'responder' to volume expansion only if both ventricles are preload dependent. Mechanical ventilation induces cyclic changes in left ventricular (LV) stroke volume, which are mainly related to the expiratory decrease in LV preload due to the inspiratory decrease in right ventricular (RV) filling and ejection. In the present review, we detail the mechanisms by which mechanical ventilation should result in greater cyclic changes in LV stroke volume when both ventricles are 'preload dependent'. We also address recent clinical data demonstrating that respiratory changes in arterial pulse (or systolic) pressure and in Doppler aortic velocity (as surrogates of respiratory changes in LV stroke volume) can be used to detect biventricular preload dependence, and hence fluid responsiveness in critically ill patients.

A tale of two compartments: interstitial versus blood glucose monitoring

Self-monitoring of blood glucose was described as one of the most important advancements in diabetes management since the invention of insulin in 1920. Recent advances in glucose sensor technology for measuring interstitial glucose concentrations have challenged the dominance of glucose meters in diabetes management, while raising questions about the relationships between interstitial and blood glucose levels. This article will review the differences between interstitial and blood glucose and some of the challenges in measuring interstitial glucose levels accurately.

The value of vital sign trends in predicting and monitoring clinical deterioration: A systematic review

BACKGROUND

Vital signs, i.e. respiratory rate, oxygen saturation, pulse, blood pressure and temperature, are regarded as an essential part of monitoring hospitalized patients. Changes in vital signs prior to clinical deterioration are well documented and early detection of preventable outcomes is key to timely intervention. Despite their role in clinical practice, how to best monitor and interpret them is still unclear.

OBJECTIVE

To evaluate the ability of vital sign trends to predict clinical deterioration in patients hospitalized with acute illness.

DATA SOURCES

PubMed, Embase, Cochrane Library and CINAHL were searched in December 2017.

STUDY SELECTION

Studies examining intermittently monitored vital sign trends in acutely ill adult patients on hospital wards and in emergency departments. Outcomes representing clinical deterioration were of interest.

DATA EXTRACTION

Performed separately by two authors using a preformed extraction sheet.

RESULTS

Of 7,366 references screened, only two were eligible for inclusion. Both were retrospective cohort studies without controls. One examined the accuracy of different vital sign trend models using discrete-time survival analysis in 269,999 admissions. One included 44,531 medical admissions examining trend in Vitalpac Early Warning Score weighted vital signs. They stated that vital sign trends increased detection of clinical deterioration. Critical appraisal was performed using evaluation tools. The studies had moderate risk of bias, and a low certainty of evidence. Additionally, four studies examining trends in early warning scores, otherwise eligible for inclusion, were evaluated.

CONCLUSIONS

This review illustrates a lack of research in intermittently monitored vital sign trends. The included studies, although heterogeneous and imprecise, indicates an added value of trend analysis. This highlights the need for well-controlled trials to thoroughly assess the research question.

Review of ICT-based services for identified unmet needs in people with dementia

Some of the needs that people with dementia and their informal carers currently perceive as insufficiently met by regular care and support services might be alleviated, or even be met, using modern Information and Communication Technology (ICT). The study described in this paper was designed to provide an insight into the state of the art in ICT solutions that could contribute to meet the most frequently mentioned unmet needs by people with dementia and their informal carers. These needs can be summarized as (1) the need for general and personalized information; (2) the need for support with regard to symptoms of dementia; (3) the need for social contact and company; and (4) the need for health monitoring and perceived safety. Databases that were searched include: PubMed, Cinahl, Psychinfo, Google (Scholar), INSPEC and IEEE. In total 22 websites and 46 publications were included that satisfied the following criteria: the article reports on people with dementia and/or their informal carers and discusses an ICT-device that has been tested within the target group and has proven to be helpful. Within the first need area 18 relevant websites and three studies were included; within the second need area 4 websites and 20 publications were included. Within the third and fourth need area 11 and 12 publications were included respectively. Most articles reported on uncontrolled studies. It is concluded that the informational websites offer helpful information for carers but seem less attuned to the person with dementia and do not offer personalized information. ICT solutions aimed at compensating for disabilities, such as memory problems and daily activities demonstrate that people with mild to moderate dementia are capable of handling simple electronic equipment and can benefit from it in terms of more confidence and enhanced positive effect. Instrumental ICT-support for coping with behavioral and psychological changes in dementia is relatively disregarded as yet, while support for social contact can be effectively realized through, for example, simplified (mobile) phones or videophones or (entertainment) robots. GPS technology and monitoring systems are proven to result in enhanced feelings of safety and less fear and anxiety. Though these results are promising, more controlled studies in which the developed ICT solutions are tested in real life situations are needed before implementing them in the care for people with dementia. It is recommended that future studies also focus on the integration of the current techniques and solutions.

Development, implementation, and impact of an automated early warning and response system for sepsis

BACKGROUND

Early recognition and timely intervention significantly reduce sepsis-related mortality.

OBJECTIVE

Describe the development, implementation, and impact of an early warning and response system (EWRS) for sepsis.

DESIGN

After tool derivation and validation, a preimplementation/postimplementation study with multivariable adjustment measured impact.

SETTING

Urban academic healthcare system.

PATIENTS

Adult non-ICU patients admitted to acute inpatient units from October 1, 2011 to October 31, 2011 for tool derivation, June 6, 2012 to July 5, 2012 for tool validation, and June 6, 2012 to September 4, 2012 and June 6, 2013 to September 4, 2013 for the preimplementation/postimplementation analysis.

INTERVENTION

An EWRS in our electronic health record monitored laboratory values and vital signs in real time. If a patient had ≥4 predefined abnormalities at any single time, the provider, nurse, and rapid response coordinator were notified and performed an immediate bedside patient evaluation.

MEASUREMENTS

Screen positive rates, test characteristics, predictive values, and likelihood ratios; system utilization; and resulting changes in processes and outcomes.

RESULTS

The tool's screen positive, sensitivity, specificity, and positive and negative predictive values and likelihood ratios for our composite of intensive care unit (ICU) transfer, rapid response team call, or death in the derivation cohort was 6%, 16%, 97%, 26%, 94%, 5.3, and 0.9, respectively. Validation values were similar. The EWRS resulted in a statistically significant increase in early sepsis care, ICU transfer, and sepsis documentation, and decreased sepsis mortality and increased discharge to home, although neither of these latter 2 findings reached statistical significance.

CONCLUSIONS

An automated prediction tool identified at-risk patients and prompted a bedside evaluation resulting in more timely sepsis care, improved documentation, and a suggestion of reduced mortality.

Wearable Biosensors: An Alternative and Practical Approach in Healthcare and Disease Monitoring

With the increasing prevalence of growing population, aging and chronic diseases continuously rising healthcare costs, the healthcare system is undergoing a vital transformation from the traditional hospital-centered system to an individual-centered system. Since the 20th century, wearable sensors are becoming widespread in healthcare and biomedical monitoring systems, empowering continuous measurement of critical biomarkers for monitoring of the diseased condition and health, medical diagnostics and evaluation in biological fluids like saliva, blood, and sweat. Over the past few decades, the developments have been focused on electrochemical and optical biosensors, along with advances with the non-invasive monitoring of biomarkers, bacteria and hormones, etc. Wearable devices have evolved gradually with a mix of multiplexed biosensing, microfluidic sampling and transport systems integrated with flexible materials and body attachments for improved wearability and simplicity. These wearables hold promise and are capable of a higher understanding of the correlations between analyte concentrations within the blood or non-invasive biofluids and feedback to the patient, which is significantly important in timely diagnosis, treatment, and control of medical conditions. However, cohort validation studies and performance evaluation of wearable biosensors are needed to underpin their clinical acceptance. In the present review, we discuss the importance, features, types of wearables, challenges and applications of wearable devices for biological fluids for the prevention of diseased conditions and real-time monitoring of human health. Herein, we summarize the various wearable devices that are developed for healthcare monitoring and their future potential has been discussed in detail.

Wearable technology in epilepsy: The views of patients, caregivers, and healthcare professionals

PURPOSE

In recent years, digital technology and wearable devices applied to seizure detection have progressively become available. In this study, we investigated the perspectives of people with epilepsy (PWE), caregivers (CG), and healthcare professionals (HP). We were interested in their current use of digital technology as well as their willingness to use wearables to monitor seizures. We also explored the role of factors influencing engagement with technology, including demographic and clinical characteristics, data confidentiality, need for technical support, and concerns about strain or increased workload.

METHODS

An online survey drawing on previous data collected via focus groups was constructed and distributed via a web link. Using logistic regression analyses, demographic, clinical, and other factors identified to influence engagement with technology were correlated with reported use and willingness to use digital technology and wearables for seizure tracking.

RESULTS

Eighty-seven surveys were completed, fifty-two (59.7%) by PWE, 13 (14.4%) by CG, and 22 (25.3%) by HP. Responders were familiar with multiple digital technologies, including the Internet, smartphones, and personal computers, and the use of digital services was similar to the UK average. Moreover, age and disease-related factors did not influence access to digital technology. The majority of PWE were willing to use a wearable device for long-term seizure tracking. However, only a limited number of PWE reported current regular use of wearables, and nonusers attributed their choice to uncertainty about the usefulness of this technology in epilepsy care. People with epilepsy envisaged the possibility of understanding their condition better through wearables and considered, with caution, the option to send automatic emergency calls. Despite concerns around accuracy, data confidentiality, and technical support, these factors did not limit PWE's willingness to use digital technology. Caregivers appeared willing to provide support to PWE using wearables and perceived a reduction of their workload and anxiety. Healthcare professionals identified areas of application for digital technologies in their clinical practice, pending an appropriate reorganization of the clinical team to share the burden of data reviewing and handling.

CONCLUSIONS

Unlike people who have other chronic health conditions, PWE appeared not to be at risk of digital exclusion. This study highlighted a great interest in the use of wearable technology across epilepsy service users, carers, and healthcare professionals, which was independent of demographic and clinical factors and outpaced data security and technology usability concerns.

RADAR-Base: Open Source Mobile Health Platform for Collecting, Monitoring, and Analyzing Data Using Sensors, Wearables, and Mobile Devices

BACKGROUND

With a wide range of use cases in both research and clinical domains, collecting continuous mobile health (mHealth) streaming data from multiple sources in a secure, highly scalable, and extensible platform is of high interest to the open source mHealth community. The European Union Innovative Medicines Initiative Remote Assessment of Disease and Relapse-Central Nervous System (RADAR-CNS) program is an exemplary project with the requirements to support the collection of high-resolution data at scale; as such, the Remote Assessment of Disease and Relapse (RADAR)-base platform is designed to meet these needs and additionally facilitate a new generation of mHealth projects in this nascent field.

OBJECTIVE

Wide-bandwidth networks, smartphone penetrance, and wearable sensors offer new possibilities for collecting near-real-time high-resolution datasets from large numbers of participants. The aim of this study was to build a platform that would cater for large-scale data collection for remote monitoring initiatives. Key criteria are around scalability, extensibility, security, and privacy.

METHODS

RADAR-base is developed as a modular application; the backend is built on a backbone of the highly successful Confluent/Apache Kafka framework for streaming data. To facilitate scaling and ease of deployment, we use Docker containers to package the components of the platform. RADAR-base provides 2 main mobile apps for data collection, a Passive App and an Active App. Other third-Party Apps and sensors are easily integrated into the platform. Management user interfaces to support data collection and enrolment are also provided.

RESULTS

General principles of the platform components and design of RADAR-base are presented here, with examples of the types of data currently being collected from devices used in RADAR-CNS projects: Multiple Sclerosis, Epilepsy, and Depression cohorts.

CONCLUSIONS

RADAR-base is a fully functional, remote data collection platform built around Confluent/Apache Kafka and provides off-the-shelf components for projects interested in collecting mHealth datasets at scale.

Intracranial Pressure Monitoring-Review and Avenues for Development

Intracranial pressure (ICP) monitoring is a staple of neurocritical care. The most commonly used current methods of monitoring in the acute setting include fluid-based systems, implantable transducers and Doppler ultrasonography. It is well established that management of elevated ICP is critical for clinical outcomes. However, numerous studies show that current methods of ICP monitoring cannot reliably define the limit of the brain's intrinsic compensatory capacity to manage increases in pressure, which would allow for proactive ICP management. Current work in the field hopes to address this gap by harnessing live-streaming ICP pressure-wave data and a multimodal integration with other physiologic measures. Additionally, there is continued development of non-invasive ICP monitoring methods for use in specific clinical scenarios.

Implantable chemical sensors for real-time clinical monitoring: progress and challenges

Recently, progress has been made in the development of implantable chemical sensors capable of real-time monitoring of clinically important species such as PO(2), PCO(2), pH, glucose and lactate. The need for developing truly biocompatible materials for sensor fabrication remains the most significant challenge for achieving robust and reliable sensors capable of monitoring the real-time physiological status of patients.

Trends in complexity of diabetes care in the United States from 1991 to 2000

BACKGROUND

During the decade from 1991 to 2000, the standard of care for diabetes mellitus evolved to require more intensive management of glycemia, blood pressure, and cholesterol levels.

METHODS

To assess changes in the complexity of outpatient management of diabetes, we used nationally representative data from the National Ambulatory Medical Care Survey. For 4708 primary care visits by patients with diabetes from 1991 to 2000, we characterized trends in the number of prescribed medicines, management of hyperglycemia, hypertension, and hyperlipidemia, provision of diabetes-related ambulatory services, and visit length.

RESULTS

From 1991 to 2000, the annual proportion of primary care visits listing at least 5 prescription medicines increased from 18.2% to 29.9% (P<.001). We found increases in visits listing oral medications for control of glucose levels (37.2% to 50.5%; P<.001), antihypertensive agents (35.9% to 42.3%; P<.001), and medications for lowering of lipid levels (4.1% to 17.3%; P<.001), whereas visits listing insulin treatment decreased from 25.3% in 1991 to 15.3% in 2000 (P<.001). Provision of diabetes-related ambulatory services remained stable (blood pressure measurement, cholesterol level testing, and dietary and smoking cessation counseling) or increased (exercise counseling; P =.01). The proportion of visits longer than 20 minutes increased from 17.8% in 1991 to 20.9% in 2000 (P =.02 for trend).

CONCLUSIONS

Office-based management of diabetes has changed significantly during the study decade. We found a marked increase in medical regimen complexity, a modest increase in visit length, and stable or increased provision of diabetes-related screening and counseling services. The increasing complexity of medical care combined with limited time during clinic visits may represent a barrier to achieving evidence-based goals of diabetes care.

Longitudinal adherence to fecal occult blood testing impacts colorectal cancer screening quality

OBJECTIVES

Existing cross-sectional quality measures for colorectal cancer (CRC) screening do not assess longitudinal adherence and thus may overestimate the quality of care. Our goal was to evaluate the adherence to repeated yearly fecal occult blood tests (FOBTs) in order to better understand the extent to which longitudinal adherence may impact screening quality.

METHODS

This was a retrospective cohort analysis of 1,122,645 patients aged 50-75 years seen at any of the 136 Department of Veterans Affairs medical centers across the United States in 2000 and followed through 2005. The primary outcome was receipt of adequate CRC screening as defined by receipt of FOBTs in at least 4 out of 5 years or receipt of any number of FOBTs in addition to at least one colonoscopy, flexible sigmoidoscopy, or double-contrast barium enema. In a predefined subset of patients receiving exclusively FOBT, adherence with repeated testing was determined over the 5-year study period.

RESULTS

Only 41.1% of men and 43.6% of women received adequate screening. Of the 384,527 men who received exclusively FOBT, 42.1% received a single FOBT, 26.0% received 2 tests, 17.8% received 3 tests, and only 14.1% were documented to have received at least 4 tests during the study period. Among the 10,469 female veterans receiving FOBT alone, rates were similar with only 13.7% completing at least 4 FOBTs in the 5-year study period.

CONCLUSIONS

Adherence to repeated FOBT is low, suggesting that cross-sectional measurements of quality may overestimate the programmatic success of CRC screening.

Advances in ICP monitoring techniques

With the advent of newer devices for measuring intracranial pressure (ICP) and cerebral metabolism, more alternatives continue to rise aiming to control ICP. This manuscript presents a proposed analysis of different ICP monitoring devices in order to make appropriate selection of them in our clinical setting including general and pediatric applications. A systematic review of the literature was made analyzing the technical advances in ICP monitoring. The recent in vitro and in vivo tests as well as mathematical/computer models were reviewed. Practical applications of principles were discussed and compared based on the mode of pressure transformation. A ventricular catheter connected to an external strain gauge transducer or catheter tip pressure transducer device is considered to be the most accurate method of monitoring ICP and enables therapeutic CSF drainage. The significant infections or hemorrhage associated with ICP devices causing patients morbidity are clinically rare and should not deter the decision to monitor ICP. Parenchymal catheter tip pressure transducer devices are advantageous when ventricular ICP cannot be obtained or if there is an obstruction in the fluid couple, though they have the potential for significant measurement differences and drift due to the inability to recalibrate. Subarachnoid or subdural fluid-coupled devices and epidural ICP devices are currently less accurate. With an increasing miniaturization of the transducers, fiberoptic systems have been developed, however, there is a problem of measurement accuracy during the period of patient monitoring and external calibration should be performed frequently to ensure constant accuracy. Ventriculostomies continue to have a pivotal role in ICP control. With a rational understanding of the applications and limitations of the different ICP monitoring devices, the outcome for critically ill neurological patients is optimized.

Perioperative management and monitoring in anaesthesia

In recent years, several risk factors for adverse outcome in patients undergoing anaesthesia have been identified. Besides human errors, cardiovascular and respiratory complications are associated with substantial morbidity. Assessment of complications has promoted the introduction of basic physiological monitoring in clinical practice. Whether monitoring directly affects outcome is not proven; however, circumstantial evidence suggests that basic cardiorespiratory monitoring decreases the incidence of serious accidents. Prevention of hypothermia also reduces anaesthesia-related morbidity. Measurement of body temperature is mandatory, and active warming is a simple, effective technique to avoid hypothermia. Evidence is growing that patients with known or suspected coronary artery disease should be treated with beta blockers perioperatively. Whether the type of anaesthesia-ie, general or regional-is relevant to perioperative mortality remains unclear. In subgroups of patients at high risk, neuraxial anaesthesia reduces the rate of respiratory and cardiovascular complications.

The perception of cancer risk in patients with prevalent Barrett's esophagus enrolled in an endoscopic surveillance program

BACKGROUND & AIMS

Patients with Barrett's esophagus (BE) have a risk of esophageal adenocarcinoma of approximately 0.5% per year. Patients may have difficulty understanding this risk. This study assessed the perceived risk of cancer in patients with BE, and correlated their risk estimates with their health care use behaviors.

METHODS

We performed a survey of patients with BE participating in an endoscopic surveillance program at 2 sites: a university teaching hospital and a Veterans' Administration hospital. A questionnaire also elicited their demographics as well as their sources of health information. Health care behaviors, including physician visits and endoscopic surveillance behaviors, were assessed. Patients were classified as either overestimators or nonoverestimators of risk. Characteristics of overestimators, as well as health care use patterns, were assessed.

RESULTS

One hundred eighteen patients met entry criteria, and 92 (78%) completed all the questionnaires. Sixty-eight percent of patients overestimated their 1-year risk of cancer, with a mean estimated 1-year cancer risk being 13.6%. The lifetime risk also was overestimated by 38% of patients. Patients who overestimated risk were more likely to be Veterans' Administration medical center patients, have more symptomatic reflux, and were more likely to use the Internet to get health care information. There was no significant difference in physician visits between overestimators and nonestimators (1.2 visits per year vs 1.0, P = .20), nor in endoscopy use (5.7 endoscopies per 5-year period vs 5.0, P = .42).

CONCLUSIONS

The majority of patients with prevalent BE participating in an endoscopic surveillance program overestimated their chances of developing adenocarcinoma of the esophagus. Efforts to improve education of such patients with BE are warranted.

Fluid administration for acute circulatory dysfunction using basic monitoring: narrative review and expert panel recommendations from an ESICM task force

An international team of experts in the field of fluid resuscitation was invited by the ESICM to form a task force to systematically review the evidence concerning fluid administration using basic monitoring. The work included a particular emphasis on pre-ICU hospital settings and resource-limited settings. The work focused on four main questions: (1) What is the role of clinical assessment to guide fluid resuscitation in shock? (2) What basic monitoring is required to perform and interpret a fluid challenge? (3) What defines a fluid challenge in terms of fluid type, ranges of volume, and rate of administration? (4) What are the safety endpoints during a fluid challenge? The expert panel found insufficient evidence to provide recommendations according to the GRADE system, and was only able to make recommendations for basic interventions, based on the available evidence and expert opinion. The panel identified significant gaps in the scientific evidence on fluid administration outside the ICU (excluding the operating theater). Globally, scientific communities and health care systems should address these critical gaps in evidence through research on how basic fluid administration in resource-rich and resource-limited settings can be improved for the benefit of patients and societies worldwide.

Ophthalmic glucose monitoring using disposable contact lenses--a review

We have developed a range of disposable and colorless tear glucose sensing contact lenses, using off-the-shelf lenses embedded with new water soluble, highly fluorescent and glucose sensitive boronic acid containing fluorophores. The new lenses are readily able to track tear glucose levels and therefore blood glucose levels, which are ideally suited for potential use by diabetics. The fluorescence responses from the lenses can be monitored using simple excitation and emission detection devices. The novelty of our approach is two fold. Firstly, the notion of sensing extremely low glucose concentrations in tears, which track blood levels, by our contact lens approach, and secondly, the unique compatibility of our new glucose signaling probes with the internal mildly acidic contact lens environment. The new lenses are therefore ideal for the non-invasive and continuous monitoring of tear glucose, with about 15-min response time, and a measured shelf life in excess of 3 months. In this review article, we show that fluorescence based signaling using plastic disposable lenses, which have already been industrially optimized with regard to vision correction and oxygen/analyte permeability etc, may a notable alternative to invasive and random finger pricking, the most widely used glucose monitoring technology by diabetics.

Advanced Wearable Microfluidic Sensors for Healthcare Monitoring

Wearable flexible sensors based on integrated microfluidic networks with multiplex analysis capability are emerging as a new paradigm to assess human health status and show great potential in application fields such as clinical medicine and athletic monitoring. Well-designed microfluidic sensors can be attached to the skin surface to acquire various pieces of physiological information with high precision, such as sweat loss, information regarding metabolites, and electrolyte balance. Herein, the recent progress of wearable microfluidic sensors for applications in healthcare monitoring is summarized, including analysis principles and microfabrication methods. Finally, the challenges and opportunities for wearable microfluidic sensors in practical applications are discussed.

Multimodality monitoring in neurocritical care

Multimodality monitoring of cerebral physiology encompasses the application of different monitoring techniques and integration of several measured physiologic and biochemical variables into assessment of brain metabolism, structure, perfusion, and oxygenation status. Novel monitoring techniques include transcranial Doppler ultrasonography, neuroimaging, intracranial pressure, cerebral perfusion, and cerebral blood flow monitors, brain tissue oxygen tension monitoring, microdialysis, evoked potentials, and continuous electroencephalogram. Multimodality monitoring enables immediate detection and prevention of acute neurologic injury as well as appropriate intervention based on patients' individual disease states in the neurocritical care unit. Real-time analysis of cerebral physiologic, metabolic, and cardiovascular parameters simultaneously has broadened knowledge about complex brain pathophysiology and cerebral hemodynamics. Integration of this information allows for more precise diagnosis and optimization of management of patients with brain injury.

Multimodal monitoring in traumatic brain injury: current status and future directions

Traumatic brain injury (TBI) remains a major cause of morbidity and mortality, particularly in young people. Despite encouraging animal studies, human trials assessing the use of pharmacological agents after TBI have all failed to show efficacy. Current management strategies are therefore directed towards providing an optimal physiological environment in order to minimize secondary insults and maximize the body's own regenerative processes. Modern neurocritical care management utilizes a host of monitoring techniques to identify or predict the occurrence of secondary insults and guide subsequent therapeutic interventions in an attempt to minimize the resulting secondary injury. Recent data suggest that the use of protocolized management strategies, informed by multimodality monitoring, can improve patient outcome after TBI. Developments in multimodality monitoring have allowed a movement away from rigid physiological target setting towards an individually tailored, patient-specific, approach. The wealth of monitoring information available provides a challenge in terms of data integration and accessibility and modern software applications may aid this process.

The effects of passive leg raising may be detected by the plethysmographic oxygen saturation signal in critically ill patients

BACKGROUND

A passive leg raising (PLR) test is positive if the cardiac index (CI) increased by > 10%, but it requires a direct measurement of CI. On the oxygen saturation plethysmographic signal, the perfusion index (PI) is the ratio between the pulsatile and the non-pulsatile portions. We hypothesised that the changes in PI could predict a positive PLR test and thus preload responsiveness in a totally non-invasive way.

METHODS

In patients with acute circulatory failure, we measured PI (Radical-7) and CI (PiCCO2) before and during a PLR test and, if decided, before and after volume expansion (500-mL saline).

RESULTS

Three patients were excluded because the plethysmography signal was absent and 3 other ones because it was unstable. Eventually, 72 patients were analysed. In 34 patients with a positive PLR test (increase in CI ≥ 10%), CI and PI increased during PLR by 21 ± 10% and 54 ± 53%, respectively. In the 38 patients with a negative PLR test, PI did not significantly change during PLR. In 26 patients in whom volume expansion was performed, CI and PI increased by 28 ± 14% and 53 ± 63%, respectively. The correlation between the PI and CI changes for all interventions was significant (r = 0.64, p < 0.001). During the PLR test, if PI increased by > 9%, a positive response of CI (≥ 10%) was diagnosed with a sensitivity of 91 (76-98%) and a specificity of 79 (63-90%) (area under the receiver operating characteristics curve 0.89 (0.80-0.95), p < 0.0001).

CONCLUSION

An increase in PI during PLR by 9% accurately detects a positive response of the PLR test.

TRIAL REGISTRATION

ID RCB 2016-A00959-42. Registered 27 June 2016.

Metabolomics in human type 2 diabetes research

The high prevalence of diabetes and diabetic complications has caused a huge burden on the modern society. Although scientific advances have led to effective strategies for preventing and treating diabetes over the past several decades, little progress has been made toward curing the disease or even getting it under control, from a public health and overall societal standpoint. There is still a lack of reliable biomarkers indicative of metabolic alterations associated with diabetes and different drug responses, highlighting the need for the development of early diagnostic and prognostic markers for diabetes and diabetic complications. The emergence of metabolomics has allowed researchers to systemically measure the small molecule metabolites, which are sensitive to the changes of both environmental and genetic factors and therefore, could be regarded as the link between genotypes and phenotypes. During the last decade, the progression made in metabolomics has provided insightful information on disease development and disease onset prediction. Recent studies using metabolomics approach coupled with statistical tools to predict incident diabetes revealed a number of metabolites that are significantly altered, including branched-chain and aromatic amino acids, such as isoleucine, leucine, valine, tyrosine and phenylalanine, as diagnostic or highly-significant predictors of future diabetes. This review summarizes the current findings of metabolomic studies in human investigations with the most common form of diabetes, type 2 diabetes.

WSES consensus conference guidelines: monitoring and management of severe adult traumatic brain injury patients with polytrauma in the first 24 hours

The acute phase management of patients with severe traumatic brain injury (TBI) and polytrauma represents a major challenge. Guidelines for the care of these complex patients are lacking, and worldwide variability in clinical practice has been documented in recent studies. Consequently, the World Society of Emergency Surgery (WSES) decided to organize an international consensus conference regarding the monitoring and management of severe adult TBI polytrauma patients during the first 24 hours after injury. A modified Delphi approach was adopted, with an agreement cut-off of 70%. Forty experts in this field (emergency surgeons, neurosurgeons, and intensivists) participated in the online consensus process. Sixteen recommendations were generated, with the aim of promoting rational care in this difficult setting.