Emergency department rapid response systems: the case for a standardized approach to deteriorating patients

Objectives: 

The timing of Rapid-Response Team activations: a multicentre international study

Background:
Most studies of Rapid-Response Teams (RRTs) assess their effect on outcomes of all hospitalised patients. Little information exists on RRT activation patterns or why RRT calls are needed. Triage error may necessitate RRT review of ward patients shortly after hospital admission. RRT diurnal activation rates may reflect the likely frequency of caregiver visits.

Objectives:
To study the timing of RRT calls in relation to time of day and day of week, and their frequency and outcomes in relation to days after hospital admission.

Methods:
We prospectively studied RRT calls over 1 month in seven hospitals during 2009, collecting data on patient age, sex, admitting unit, admission source, limitations of medical therapy (LOMTs), and admission and discharge dates. We assessed the timing of RRT calls in relation to hospital admission and circadian variation; and differences in characteristics and outcomes of calls occurring early (Days 0 and 1) versus late (after Day 7) after hospital admission.

Results:
There were 652 RRT calls for 518 patients. Calls were more likely on Mondays (P=0.018) and during work hours (P<0.0001) but less likely on weekends (P=0.003) or overnight (P<0.001). There were 177 early calls (27.1%) and 198 late calls (30.4%). Early calls involved younger patients (median ages, 67.5 years [early calls] v 73 years [late calls]; P= 0.01), fewer LOMTs (P=0.029), and lower in hospital mortality (12.8% [early calls] v 32.3% [late calls]; P<0.0001). The mortality difference remained in patients without LOMTs (5.6% [early calls] v 19.6% [late calls]; P=0.003).

Conclusions:
About one-quarter of RRT calls occurred shortly after hospital admission, and were more common when caregivers were around. Early calls may partially reflect suboptimal triage, though the associated mortality appeared low. Late calls may reflect suboptimal end-of-life care planning, and the associated mortality was high. There is a need to further assess the epidemiology of RRT calls at different phases of the hospital stay.

Characteristics and outcomes of patients requiring rapid response system activation within 24 hours of emergency admission

Objectives: 

Findings of the first ANZICS conference on the role of intensive care in Rapid Response Teams.

Rapid Response Teams (RRTs) are specialised teams introduced into hospitals to improve the outcomes of deteriorating ward patients. Although Rapid Response Systems (RRSs) were developed by the intensive care unit (ICU) community, there is variability in their delivery, and consultant involvement, supervision and leadership appears to be relatively infrequent. In July 2014, the Australian and New Zealand Intensive Care Society (ANZICS) convened the first conference on the role of intensive care medicine in RRTs in Australia and New Zealand. The conference explored RRSs in the broader role of patient safety, resourcing and staffing of RRTs, effect on ICU workload, different RRT models, the outcomes of RRT patients and original research projects in the area of RRSs. Issues around education and training of both ICU registrars and nurses were examined, and the role of team training explored. Measures to assess the effectiveness of the RRS and RRT at the level of health system and hospital, team performance and team effectiveness were discussed, and the need to develop a bi-national ANZICS RRT patient database was presented. Strategies to prevent patient deterioration in the 'pre-RRT' period were discussed, including education of ward nurses and doctors, as well as an overarching governance structure. The role of the ICU in deteriorating ward patients was debated and an integrated model of acute care presented. This article summarises the findings of the conference and presents recommendations on the role of intensive care medicine in RRTs in Australia and New Zealand.

Epidemiology of early Rapid Response Team activation after emergency department admission

BACKGROUND: Rapid Response Team (RRT) calls can often occur within 24h of hospital admission to a general ward. We seek to determine whether it is possible to identify these patients before there is a significant clinical deterioration. METHODS: Retrospective case-controlled study comparing patient characteristics, vital signs, and hospital outcomes in patients triggering RRT activation within 24h of ED admission (cases) with matched ED admissions not receiving a RRT call (controls). RESULTS: Over 12 months, there were 154 early RRT calls. Compared with controls, cases had a higher heart rate (HR) at triage (92 vs. 84beats/min; p=0.008); after 3h in the ED (91 vs. 80beats/min; p=0.0007); and at ED discharge (91 vs. 81beats/min; p=0.0005). Respiratory rate (RR) was also higher at triage (21.2 vs. 19.2breaths/min; p=0.001). On multiple variable analysis, RR at triage and HR before ward transfer predicted early RRT activation: OR 1.07 [95% CI 1.02-1.12] for each 1breath/min increase in RR; and 1.02 [95% CI 1.002-1.030] for each beat/minute increase in HR, respectively. Study patients required transfer to the intensive care in approximately 20% of cases and also had a greater mortality: (21% vs. 6%; OR 4.65 [95% CI 1.86-11.65]; p=0.0003) compared with controls. CONCLUSIONS: Patients that trigger RRT calls within 24h of admission have a fourfold increase in risk of in-hospital mortality. Such patients may be identified by greater tachycardia and tachypnoea in the ED.

Clinical review criteria and medical emergency teams: evaluating a two-tier rapid response system

OBJECTIVES: To assess the prevalence of patients fulfilling clinical review criteria (CRC), to determine activation rates for CRC assessments, to compare baseline characteristics and outcomes of patients who fulfilled CRC with patients who did not, and to identify the documented nursing actions in response to CRC values. DESIGN, SETTING AND PARTICIPANTS: A cross-sectional study using a retrospective medical record audit, in a universityaffiliated, tertiary referral hospital with a two-tier rapid response system in Melbourne, Australia. We used a convenience sample of hospital inpatients on general medical, surgical and specialist service wards admitted during a 24-hour period in 2013. MAIN OUTCOME MEASURES: Medical emergency team (MET) or code blue activation, unplanned intensive care unit admissions, hospital length of stay and inhospital mortality. For patients who fulfilled CRC or MET criteria during the 24- hour period, the specific criteria fulfilled, escalation treatments and outcomes were collected. RESULTS: Of the sample (N = 422), 81 patients (19%) fulfilled CRC on 109 occasions. From 109 CRC events, 66 patients (81%) had at least one observation fulfilling CRC, and 15 patients (18%) met CRC on multiple occasions. The documented escalation rate was 58 of 109 events (53%). The number of patients who fulfilled CRC and subsequent MET call activation criteria within 24 hours was significantly greater than the number who did not meet CRC (P < 0.001). CONCLUSIONS: About one in five patients reached CRC during the study period; these patients were about four times more likely to also fulfil MET call criteria. Contrary to hospital policy, escalation was not documented for about half the patients meeting CRC values. Despite the clarity of escalation procedures on the graphic observation chart, escalation remains an ongoing problem. Further research is needed on the impact on patient outcomes over time and to understand factors influencing staff response.

The effect of a staged, emergency department specific rapid response system on reporting of clinical deterioration

BACKGROUND: Despite emerging evidence regarding clinical deterioration in emergency department (ED) patients, the widespread uptake of rapid response systems (RRS) in EDs has been limited. AIMS: To evaluate the effect of an ED RRS on reporting of clinical deterioration and determine if there were differences between patients who did, and did not, deteriorate during ED care. METHODS: A retrospective cross sectional design was used to conduct this single site study in Melbourne, Australia. Stratified random sampling identified 50 patients with shortness of breath, chest pain or abdominal pain per each year studied (2009-2012) giving a total of 600 patients. The intervention was an ED RRS implemented in stages. RESULTS: The frequency of clinical deterioration was 14.8% (318 episodes/89 patients). Unreported deterioration decreased each year (86.7%; 68.8%; 55.3%; 54.0%, p=0.141). Patients who deteriorated during ED care had a longer median ED length of stay (2.8h; p<0.001), were 31.9% more likely to need hospital admission (p<0.001) and 4.9% more likely to die in hospital (p=0.044). CONCLUSIONS: A staged ED specific RRS decreased the frequency of unreported clinical deterioration. Controlled multi-site studies of ED specific RRSs are needed to examine the effect of formal ED RRSs on patient outcomes.

The epidemiology of sepsis during rapid response team reviews in a teaching hospital

In a three-month retrospective study, we assessed the proportion of rapid response team (RRT) calls associated with systemic inflammatory response syndrome (SIRS) and sepsis. We also documented the site of infection (whether it was community- or hospital-acquired), antibiotic modifications after the call and in-hospital outcomes. Amongst 358 RRT calls, two or more SIRS criteria were present in 277 (77.4%). Amongst the 277 RRT calls with SIRS criteria, 159 (57.4%) fulfilled sepsis criteria in the 24 hours before and 12 hours after the call. There were 118 of 277 (42.6%) calls with SIRS criteria but no evidence of sepsis and 62 of 277 (22.3%) calls associated with both criteria for sepsis as well as an alternative cause for SIRS. Hence, 159 (44.4%) of all 358 RRT calls over the three-month study period fulfilled criteria for sepsis and in 97 (159-62) (27.1%) of the 358 calls, there were criteria for sepsis without other causes for SIRS criteria. The most common sites of infection were respiratory tract (86), abdominal cavity (38), urinary tract (26) and bloodstream (26). Infection was hospital-acquired in 91 (57.2%) and community-acquired in 67 (42.1%) cases, respectively. Patients were on antibiotics in 127 of 159 (79.9%) cases before the RRT call and antibiotics were added or modified in 76 of 159 (47.8%) cases after RRT review. The hospital length-of-stay of patients who received an RRT call associated with sepsis was longer than those who did not (16.0 [8.0 to 28.5] versus 10 days [6.0 to 18.0]; P=0.002).

Patient physiological status during emergency care and rapid response team or cardiac arrest team activation during early hospital admission

OBJECTIVES: The objective of this study was to examine the relationship between rapid response team (RRT) or cardiac arrest team (CAT) activation within 72 h of emergency admission and (i) physiological status in the emergency department (ED) and (ii) risk for ICU admission and in-hospital mortality.

METHODS: A retrospective matched cohort study was conducted in three hospitals in Melbourne, Australia. The exposed cohort (n=660) included randomly selected adults admitted to the medical or surgical ward through the ED who had RRT or CAT activation within 72 h of admission. Unexposed matched controls (n=1320) did not have RRT or CAT activation.

RESULTS: The exposed cohort was more likely to have physiological abnormalities fulfilling hospital RRT activation criteria during ED care (36.7 vs. 23.8%, P<0.001). After adjusting for confounders, tachypnoea (adjusted odds ratio=1.92, 95% confidence interval: 1.38-2.67) or hypotension (AOR=1.43, 95% confidence interval: 1.00-2.03), fulfilling RRT activation criteria during ED care, was associated with RRT or CAT activation within 72 h of admission. The exposed cohort had more in-hospital deaths (16.5 vs. 3.6%, P<0.001), more unexpected in-hospital deaths (2.05 vs. 0.2%, P<0.001), more ICU admissions (11.8 vs. 0.7%, P<0.001) and longer lengths of hospital stay (median=8 vs. 5 days, P<0.001).

CONCLUSION: CAT/RRT activations within 72 h of emergency admission are associated with higher mortality and increased length of stay. Factors associated with CAT/RRT activation in the wards are often identifiable when patients are in the ED. Further studies are required to determine whether early identification and intervention in patients at risk for RRT or CAT activation can improve their eventual outcomes.

Additive manufacturing technologies : 3D printing, rapid prototyping, and direct digital manufacturing

This book covers in detail the various aspects of joining materials to form parts. A conceptual overview of rapid prototyping and layered manufacturing is given, beginning with the fundamentals so that readers can get up to speed quickly. Unusual and emerging applications such as micro-scale manufacturing, medical applications, aerospace, and rapid manufacturing are also discussed. This book provides a comprehensive overview of rapid prototyping technologies as well as support technologies such as software systems, vacuum casting, investment casting, plating, infiltration and other systems. This book also: Reflects recent developments and trends and adheres to the ASTM, SI, and other standards Includes chapters on automotive technology, aerospace technology and low-cost AM technologies Provides a broad range of technical questions to ensure comprehensive understanding of the concepts covered.

The effect of a rapid heating rate, mechanical vibration and surfactant chemistry on the structure-property relationships of epoxy/clay nanocomposites

The role of processing conditions and intercalant chemistry in montmorillonite clays on the dispersion, morphology and mechanical properties of two epoxy/clay nanocomposite systems was investigated in this paper. This work highlights the importance of employing complementary techniques (X-ray diffraction, small angle X-ray scattering, optical microscopy and transmission electron microscopy) to correlate nanomorphology to macroscale properties. Materials were prepared using an out of autoclave manufacturing process equipped to generate rapid heating rates and mechanical vibration. The results suggested that the quaternary ammonium surfactant on C30B clay reacted with the epoxy during cure, while the primary ammonium surfactant (I.30E) catalysed the polymerisation reaction. These effects led to important differences in nanocomposite clay morphologies. The use of mechanical vibration at 4 Hz prior to matrix gelation was found to facilitate clay dispersion and to reduce the area fraction of I.30E clay agglomerates in addition to increasing flexural strength by over 40%.

Rapid and sensitive ethanol sensor based on hollow Au/V2O5 nanotubes via emulsion-electrospinning route

Hollow electrospun V2O5 and Au/V2O5 nanotubes have been successfully synthesized by combining emulsion electrospinning (EE) and post calcination treatment. Immiscible polyvinyl pyrrolidone (PVP)/metal salts/dimethylformamide (DMF) solution and polystyrene (PS)/DMF solution are chosen for the EE to form PS PVP/metal salts) core-sheath nanofibers, in which PS nanorods were formed and encapsulated within in the PVP/metal salts nanofibers owing to the stretching forces and de-emulsified force during the electrospinning. Excellent sensitivity and rapid response-recovery behaviors against ethanol have been successfully achieved based on our hollow ceramic (V2O5 and Au/V2O5) nanotubes.

Optimal power allocation and load distribution for multiple heterogeneous multicore server processors across clouds and data centers

For multiple heterogeneous multicore server processors across clouds and data centers, the aggregated performance of the cloud of clouds can be optimized by load distribution and balancing. Energy efficiency is one of the most important issues for large-scale server systems in current and future data centers. The multicore processor technology provides new levels of performance and energy efficiency. The present paper aims to develop power and performance constrained load distribution methods for cloud computing in current and future large-scale data centers. In particular, we address the problem of optimal power allocation and load distribution for multiple heterogeneous multicore server processors across clouds and data centers. Our strategy is to formulate optimal power allocation and load distribution for multiple servers in a cloud of clouds as optimization problems, i.e., power constrained performance optimization and performance constrained power optimization. Our research problems in large-scale data centers are well-defined multivariable optimization problems, which explore the power-performance tradeoff by fixing one factor and minimizing the other, from the perspective of optimal load distribution. It is clear that such power and performance optimization is important for a cloud computing provider to efficiently utilize all the available resources. We model a multicore server processor as a queuing system with multiple servers. Our optimization problems are solved for two different models of core speed, where one model assumes that a core runs at zero speed when it is idle, and the other model assumes that a core runs at a constant speed. Our results in this paper provide new theoretical insights into power management and performance optimization in data centers.