[In-hospital emergencies at a surgical university hospital]

BACKGROUND

Emergency treatment and resuscitation within hospitals are managed by so-called medical emergency teams (MET). The present study examined the circumstances, number, initial treatment and further hospital course of in-hospital emergency cases at a level 1 university hospital.

METHODS

A retrospective study of in-hospital emergencies on the surgical wards of a university hospital including all non-intensive care areas from January 2007 to June 2010 was carried out. A self-developed documentation protocol which was introduced in 2006 was used by the MET to document general patient characteristics and details of the emergency treatment. These data included the place where the emergency situation arose, the patient's assignment to a surgical discipline, a detailed description of the emergency situation, the effectiveness of basic life support measures as well as the further hospital course of the patient.

RESULTS

A total of 235 emergency cases were documented within the study period of 3.5 years. The frequency of in-hospital emergencies was 4/1,000 admitted patients per year. Cardiac arrest was encountered in 31,5%. Out of all patients 54,5% were admitted to an intensive care unit.

CONCLUSION

The tasks of a MET at a surgical university hospital go beyond mere cardiopulmonary resuscitation. Emergency cases within the full spectrum of perioperative complications are encountered. Further multicenter studies with standardized protocols are required to analyze the management of German in-hospital emergencies.

Surviving sepsis: going beyond the guidelines

The Surviving Sepsis Campaign is a global effort to improve the care of patients with severe sepsis and septic shock. The first Surviving Sepsis Campaign Guidelines were published in 2004 with an updated version published in 2008. These guidelines have been endorsed by many professional organizations throughout the world and come regarded as the standard of care for the management of patients with severe sepsis. Unfortunately, most of the recommendations of these guidelines are not evidence-based. Furthermore, the major components of the 6-hour bundle are based on a single-center study whose validity has been recently under increasing scrutiny. This paper reviews the validity of the Surviving Sepsis Campaign 6-hour bundle and provides a more evidence-based approach to the initial resuscitation of patients with severe sepsis.

Haplotype association mapping of acute lung injury in mice implicates activin a receptor, type 1

RATIONALE

Because acute lung injury is a sporadic disease produced by heterogeneous precipitating factors, previous genetic analyses are mainly limited to candidate gene case-control studies.

OBJECTIVES

To develop a genome-wide strategy in which single nucleotide polymorphism associations are assessed for functional consequences to survival during acute lung injury in mice.

METHODS

To identify genes associated with acute lung injury, 40 inbred strains were exposed to acrolein and haplotype association mapping, microarray, and DNA-protein binding were assessed.

MEASUREMENTS AND MAIN RESULTS

The mean survival time varied among mouse strains with polar strains differing approximately 2.5-fold. Associations were identified on chromosomes 1, 2, 4, 11, and 12. Seven genes (Acvr1, Cacnb4, Ccdc148, Galnt13, Rfwd2, Rpap2, and Tgfbr3) had single nucleotide polymorphism (SNP) associations within the gene. Because SNP associations may encompass "blocks" of associated variants, functional assessment was performed in 91 genes within ± 1 Mbp of each SNP association. Using 10% or greater allelic frequency and 10% or greater phenotype explained as threshold criteria, 16 genes were assessed by microarray and reverse real-time polymerase chain reaction. Microarray revealed several enriched pathways including transforming growth factor-β signaling. Transcripts for Acvr1, Arhgap15, Cacybp, Rfwd2, and Tgfbr3 differed between the strains with exposure and contained SNPs that could eliminate putative transcriptional factor recognition sites. Ccdc148, Fancl, and Tnn had sequence differences that could produce an amino acid substitution. Mycn and Mgat4a had a promoter SNP or 3'untranslated region SNPs, respectively. Several genes were related and encoded receptors (ACVR1, TGFBR3), transcription factors (MYCN, possibly CCDC148), and ubiquitin-proteasome (RFWD2, FANCL, CACYBP) proteins that can modulate cell signaling. An Acvr1 SNP eliminated a putative ELK1 binding site and diminished DNA-protein binding.

CONCLUSIONS

Assessment of genetic associations can be strengthened using a genetic/genomic approach. This approach identified several candidate genes, including Acvr1, associated with increased susceptibility to acute lung injury in mice.

What blood temperature for an ex vivo extracorporeal circuit?

Ex vivo circuits are commonly used to evaluate biomaterials or devices used for extracorporeal blood purification. However, various aspects of the ex vivo circuit, apart from the circuit materials, may affect inflammation and coagulation. One such aspect is temperature. The aim of this study was to evaluate the influence of different blood temperature conditions on inflammation parameters in an ex vivo circuit. Blood was collected from 20 healthy volunteers and run through three different experimental conditions for 4 h: a miniaturized ex vivo extracorporeal circuit equipped with a blood warmer set to 37°C, the same circuit without the warmer (23°C), and a tube placed in an incubator at 37°C (no circuit). We measured the granulocyte macrophage colony-stimulating factor, the tumor necrosis factor, and the interleukin (IL)-1β, IL-6, IL-8, and IL-10 concentrations at baseline, 15, 60, 120, and 240 min. Human leukocyte antigen (HLA)-DR, CD11b, CD11a, CD62L, tumor necrosis factor alpha converting enzyme, annexin V expression, and NFkB DNA binding were measured in monocytes and polymorphonuclear neutrophils (PMNs) using flow cytometry at baseline, 120 min, and 240 min. While cytokine production over time was very slight at room temperature, levels increased by more than 100-fold in the two heated conditions. Differences in the expression of some surface markers were also observed between the room temperature circuit and the two heated conditions (CD11b PMN, P < 0.0001; HLA-DR Mono, P=0.0019; and CD11a PMN, P<0.0001). Evolution of annexin V expression was also different over time between the three groups (P=0.0178 for monocytes and P=0.0011 for PMNs). A trend for a greater NFkB DNA binding was observed in the heated conditions. Thus, for ex vivo studies using extracorporeal circuits, heating blood to maintain body temperature results in significant activation of inflammatory cells while hypothermia (room temperature) seems to suppress the leukocyte response. Both strategies may lead to erroneous conclusions, possibly masking some specific effects of the device being studied. Investigators in this field must be aware of the fact that blood temperature is a crucial confounding parameter and the type of "background noise" they will face depending on the strategy adopted.

Care bundles: implementing evidence or common sense?

Care bundles aim to improve standard of care and patient outcome by promoting the consistent implementation of a group of effective interventions. However, a variety of barriers prevent their full application in clinical practice. Here, we discuss some of the benefits and limitations of care bundles in the delivery of safer and more effective and consistent health care.

ANGPT2 genetic variant is associated with trauma-associated acute lung injury and altered plasma angiopoietin-2 isoform ratio

RATIONALE

Acute lung injury (ALI) acts as a complex genetic trait, yet its genetic risk factors remain incompletely understood. Large-scale genotyping has not previously been reported for ALI.

OBJECTIVES

To identify ALI risk variants after major trauma using a large-scale candidate gene approach.

METHODS

We performed a two-stage genetic association study. We derived findings in an African American cohort (n = 222) using a cardiopulmonary disease-centric 50K single nucleotide polymorphism (SNP) array. Genotype and haplotype distributions were compared between subjects with ALI and without ALI, with adjustment for clinical factors. Top performing SNPs (P < 10(-4)) were tested in a multicenter European American trauma-associated ALI case-control population (n = 600 ALI; n = 2,266 population-based control subjects) for replication. The ALI-associated genomic region was sequenced, analyzed for in silico prediction of function, and plasma was assayed by ELISA and immunoblot.

MEASUREMENTS AND MAIN RESULTS

Five SNPs demonstrated a significant association with ALI after adjustment for covariates in Stage I. Two SNPs in ANGPT2 (rs1868554 and rs2442598) replicated their significant association with ALI in Stage II. rs1868554 was robust to multiple comparison correction: odds ratio 1.22 (1.06-1.40), P = 0.0047. Resequencing identified predicted novel splice sites in linkage disequilibrium with rs1868554, and immunoblots showed higher proportion of variant angiopoietin-2 (ANG2) isoform associated with rs1868554T (0.81 vs. 0.48; P = 0.038).

CONCLUSIONS

An ANGPT2 region is associated with both ALI and variation in plasma angiopoietin-2 isoforms. Characterization of the variant isoform and its genetic regulation may yield important insights about ALI pathogenesis and susceptibility.

Early goal-directed therapy (EGDT) for severe sepsis/septic shock: which components of treatment are more difficult to implement in a community-based emergency department?

BACKGROUND

Early goal-directed therapy (EGDT) has been shown to reduce mortality in patients with severe sepsis/septic shock, however, implementation of this protocol in the emergency department (ED) is sometimes difficult.

OBJECTIVES

We evaluated our sepsis protocol to determine which EGDT elements were more difficult to implement in our community-based ED.

METHODS

This was a non-concurrent cohort study of adult patients entered into a sepsis protocol at a single community hospital from July 2008 to March 2009. Charts were reviewed for the following process measures: a predefined crystalloid bolus, antibiotic administration, central venous catheter insertion, central venous pressure measurement, arterial line insertion, vasopressor utilization, central venous oxygen saturation measurement, and use of a standardized order set. We also compared the individual component adherence with survival to hospital discharge.

RESULTS

A total of 98 patients presented over a 9-month period. Measures with the highest adherence were vasopressor administration (79%; 95% confidence interval [CI] 69-89%) and antibiotic use (78%; 95% CI 68-85%). Measures with the lowest adherence included arterial line placement (42%; 95% CI 32-52%), central venous pressure measurement (27%; 95% CI 18-36%), and central venous oxygen saturation measurement (15%; 95% CI 7-23%). Fifty-seven patients survived to hospital discharge (Mortality: 33%). The only element of EDGT to demonstrate a statistical significance in patients surviving to hospital discharge was the crystalloid bolus (79% vs. 46%) (respiratory rate [RR] = 1.76, 95% CI 1.11-2.58).

CONCLUSION

In our community hospital, arterial line placement, central venous pressure measurement, and central venous oxygen saturation measurement were the most difficult elements of EGDT to implement. Patients who survived to hospital discharge were more likely to receive the crystalloid bolus.

BK large conductance Ca²+-activated K+ channel-deficient mice are not resistant to hypotension and display reduced survival benefit following polymicrobial sepsis

Nitric oxide-mediated activation of large conductance calcium-activated potassium (BK) channels is considered an important underlying mechanism of sepsis-induced hypotension. Indeed, the nonselective K-channel inhibitor, tetraethylammonium chloride (TEA), has been proposed as a potential treatment to raise blood pressure in septic shock by virtue of its ability to inhibit BK channels. As experimental evidence has so far relied on pharmacological inhibition, we examined the effects of channel deletion using BKα subunit knockout (α, Slo) mice in two mouse models of polymicrobial sepsis, namely, intraperitoneal fecal slurry and cecal ligation and puncture. Comparison was made against TEA treatment in wild-type (WT) mice. Following slurry, BKα and WT mice developed similar degrees of hypotension over 10 h with no difference in cardiac output as assessed by echocardiography between groups. Tetraethylammonium chloride raised blood pressure significantly in septic WT mice, but had no effect on survival. However, following cecal ligation and puncture, a significantly reduced survival was seen in both BKα mice and (high-dose) TEA-treated WT mice compared with untreated WT animals. In conclusion, the BK channel does not appear to be integral to sepsis-induced hypotension but does affect survival through other mechanisms. The pressor effect of TEA may be related to effects on other potassium channels.

The epidemiology and outcome of medical emergency team call patients treated with non-invasive ventilation

INTRODUCTION

Use of non-invasive ventilation (NIV) is normally limited to the Emergency Department, Intensive Care Unit (ICU), Coronary Care Unit (CCU) or High Dependency Unit (HDU). However, NIV is sometimes used by the Medical Emergency Team (MET) as respiratory support for ward patients.

OBJECTIVES

We reviewed the characteristics and outcome of ward patients treated with NIV in the setting of a MET Call and determined the clinical and prognostic significance of such treatment.

METHODS

We used our MET database to assess the characteristics and outcome of patients treated with NIV and compared them to a control group of patients with similar MET diagnoses but not treated with NIV.

RESULTS

We studied 5389 calls in 3880 patients. NIV was delivered during 483 (9.0%) calls to 426 patients (11% of the total). The four most common MET diagnoses associated with NIV were acute pulmonary edema (156 calls, 32.3%), pneumonia (84 calls, 17.4%), acute respiratory failure of unclear origin (59 calls, 12.2%) and exacerbation of chronic obstructive pulmonary disease (32 calls, 6.6%). Limitations of medical therapy (LOMT) were documented in 151 (35.4%) patients. Among NIV patients without LOMT, 115 (41.8%) were transferred to ICU and 50 (18.2%) to the coronary care or high dependency unit (CCU/HDU) compared with only 50 (18.0%) and 16 (5.8%) respectively in the control group (p<0.001). Overall, 76 NIV patients (27.6%) received endotracheal intubation (ETT) compared with 61 (21.9%) in controls. Mortality was 23.6% in the NIV group versus 18.8% in the control group.

CONCLUSION

One in ten MET call patients received NIV. In those without LOMT, two thirds were transferred to ICU/HDU/CCU, one in four received ETT, and one in four died. NIV use at the time of a MET call identified high risk patients for whom admission to ICU/HDU/CCU should be strongly considered.

The effect of medical emergency teams on patient outcome: a review of the literature

This paper presents a review of literature on the impact of the medical emergency team (MET) on inpatient mortality, cardiopulmonary arrests or unscheduled intensive care unit (ICU) admissions. A total of 14,172 abstracts and 98 full text papers were reviewed. In total, 24 met the inclusion criteria, 2 used a cluster-randomized controlled trial, 11 before and after, 6 retrospective analyses, 4 prospective cohorts and 1 not reported. There is moderate to strong evidence that METs are associated with decreased mortality and cardiac arrest rates, and weak evidence on its impact on ICU admission rate reductions. This evidence suffers from the flaws with only two randomized controlled trials examining differing outcome measures with differing results. Poor methodology and failure to report both quality improvement co-interventions and time response rates of METs, limit the strength of the evidence that METs are effective interventions for preventing mortality, code rates or unscheduled ICU admissions. Studies with improved implementation practices and evaluation of the efficacy of MET is warranted.

Clinical review: Optimal dose of continuous renal replacement therapy in acute kidney injury

Continuous renal replacement therapy (CRRT) is the preferred treatment for acute kidney injury in intensive care units (ICUs) throughout much of the world. Despite the widespread use of CRRT, controversy and center-specific practice variation in the clinical application of CRRT continue. In particular, whereas two single-center studies have suggested survival benefit from delivery of higher-intensity CRRT to patients with acute kidney injury in the ICU, other studies have been inconsistent in their results. Now, however, two large multi-center randomized controlled trials - the Veterans Affairs/National Institutes of Health Acute Renal Failure Trial Network (ATN) study and the Randomized Evaluation of Normal versus Augmented Level (RENAL) Replacement Therapy Study - have provided level 1 evidence that effluent flow rates above 25 mL/kg per hour do not improve outcomes in patients in the ICU. In this review, we discuss the concept of dose of CRRT, its relationship with clinical outcomes, and what target optimal dose of CRRT should be pursued in light of the high-quality evidence now available.

Fluid administration and the kidney

PURPOSE OF REVIEW

Intravenous fluids are widely administered in the ICU with the intention of preventing or ameliorating acute kidney injury (AKI). This review focuses on recent studies examining fluid administration and renal function in critical illness to critically examine conventional justifications for fluid administration.

RECENT FINDINGS

Early, targeted, resuscitation of inadequate cardiac output in shock may have a beneficial effect on organ function and patient outcome. However, experimental evidence suggests the relationship between fluid administration and an increase in renal oxygen delivery is weak, whereas any beneficial effects from fluid administration can be short lived. Conversely, evidence associating fluid overload and adverse outcomes is strengthening, whereas more restrictive fluid administration does not seem to predispose to clinically significant AKI in many situations. Furthermore, concerns persist that some colloid or high chloride concentration solutions may directly impair renal function independent of volume overload.

SUMMARY

Adequate volume resuscitation remains a cornerstone to the emergent treatment of critical illness. However, continued fluid administration and positive fluid balances have not been shown to improve renal outcomes and may worsen overall prognosis in AKI. Concerns about renal dysfunction should not deter clinicians from adopting more restrictive approaches to fluid administration.

The deteriorating ward patient: a Swedish-Australian comparison

OBJECTIVE

Most centres in Europe have not introduced a rapid response team (RRT), partly because of concerns that data from other health-care systems may not be relevant. We tested whether patient characteristics and outcomes for deteriorating patients differ between two health-care systems separated by distance and culture.

METHODS

We obtained data from 3,063 RRT calls: 815 calls at Karolinska University Hospital (Sweden) and 2,248 calls at Austin Hospital (Australia) and compared demographic and clinical data, as well as outcomes for patients reviewed by a RRT.

RESULTS

At Karolinska, 46.9% of patients were female compared with 45.1% at Austin. Mean age was 66.5 years versus 69.4 years. The unit of admission was surgical/medical in 49.1%/50.9% versus 48.8%/51.1% of patients, respectively. Overall, 56.7% versus 55.8% of the calls were out-of-hours (1700-0800 hours). There was a predominance of respiratory triggers at both centres and the "worried" criterion was frequently used in both hospitals (17.2% versus 14.4%) as a trigger for RRT activation. Overall, 30-day mortality was 27.7% versus 29.4% and allocation of Limitations of Medical Treatment (LOMT) orders was 34.2% versus 30.8%. The allocation of LOMT orders was influenced by the RRT in 14.4% versus 12.6% of cases.

CONCLUSION

In two different health-care systems separated by geography, language, culture and organizational features, the characteristics of deteriorating ward patients, their disposal and outcomes were similar, suggesting that the care of the deteriorating ward patient is a global problem in modern hospitals and confirming that their hospital mortality is high.

Retrospective review of emergency response activations during a 13-year period at a tertiary care children's hospital

OBJECTIVES

Pediatric in-hospital arrests are uncommon but are associated with poor outcomes. In preparation for implenting a Rapid Response Team (RRT) at The Children's Hospital, we reviewed our data collection of 13 years of emergency response team (ERT) activations. We describe demographic and clinical variables, including outcomes of ERT activations at a free-standing tertiary care children's hospital.

METHODS

Analysis was performed on data collected from January 1993 through July 2007. Variables collected included age, sex, admission diagnosis, core event, admission diagnosis and secondary diagnosis, medical division or winter/nonwinter months, day/night shifts, survival of core event, survival to discharge, and primary attending service.

RESULTS

There were 1537 ERT activations in the database, 203 were eliminated due to missing data or were adult visitors/employees. The remaining 1334 were included for analysis. Our results showed 39%(511) of all ERT activations occurred in patients under 1 year of age. The most common admission diagnosis category was cardiac disease. There was no statistical significance between summer and winter months although more activations occurred during daytime hours (P < .001). Survival rate of an ERT was 90%, with a 78% survival rate to discharge.

CONCLUSION

Our data support the general belief that younger children with chronic disease are at highest risk for ERT activations. These risk factors should be taken into consideration when planning patient placement, medical staffing, and the threshold for ICU consultations or admissions. More extensive multisite studies using clinical data are necessary to further identify hospitalized children at risk for sudden decompensation.

Glyburide is anti-inflammatory and associated with reduced mortality in melioidosis

Patients with diabetes have better survival from septic melioidosis than patients who without diabetes. This difference was seen only in patients taking glyburide prior to presentation and was associated with an anti-inflammatory effect of glyburide.

Background. Patients with diabetes mellitus are more prone to bacterial sepsis, but there are conflicting data on whether outcomes are worse in diabetics after presentation with sepsis. Glyburide is an oral hypoglycemic agent used to treat diabetes mellitus. This K_ATP-channel blocker and broad-spectrum ATP-binding cassette (ABC) transporter inhibitor has broad-ranging effects on the immune system, including inhibition of inflammasome assembly and would be predicted to influence the host response to infection.

Methods. We studied a cohort of 1160 patients with gram-negative sepsis caused by a single pathogen (Burkholderia pseudomallei), 410 (35%) of whom were known to have diabetes. We subsequently studied prospectively diabetics with B. pseudomallei infection (n = 20) to compare the gene expression profile of peripheral whole blood leukocytes in patients who were taking glyburide against those not taking any sulfonylurea.

Results. Survival was greater in diabetics than in nondiabetics (38% vs 45%, respectively, P = .04), but the survival benefit was confined to the patient group taking glyburide (adjusted odds ratio .47, 95% confidence interval .28–.74, P = .005). We identified differential expression of 63 immune-related genes (P = .001) in patients taking glyburide, the sum effect of which we predict to be antiinflammatory in the glyburide group.

Conclusions. We present observational evidence for a glyburide-associated benefit during human melioidosis and correlate this with an anti-inflammatory effect of glyburide on the immune system.

Rapid response team interventions for severe hyperkalemia: evaluation of a patient safety initiative

RATIONALE

This study evaluates outcomes and process measures associated with a rapid response team (RRT) intervention for patients with severe hyperkalemia.

STUDY POPULATION

Inpatients on medical-surgical floors (excluding dialysis or comfort care patients) at a 1000-bed tertiary hospital from 2005 to 2009 with severe hyperkalemia (defined as potassium [K(+)] ≥ 6.3 mEq/L).

METHODS

Retrospective administrative data and medical record review. Hyperkalemia incidence (based both on coding data and laboratory test results) was assessed, as was the association between hyperkalemia and mortality. Independent physician reviewers adjudicated selected cases for death directly attributable to hyperkalemia and potential for preventability with the RRT intervention. All 115 Baylor University Medical Center (Dallas, TX) cases receiving the RRT hyperkalemia intervention over a 12-month period (December 2006-December 2007) underwent in-depth process assessment.

RESULTS

Hyperkalemia occurred as a codable diagnosis in approximately 3.2% of all hospital discharges annually (5-year average of 42 000 discharges), and K(+) values ≥ 6.3 mEq/L were observed in 0.8% to 0.9% of all K(+) assays run by the laboratory in the months sampled. Deaths determined to be directly related to hyperkalemia and potentially preventable were rare, with a total of only 4 events during the study period (3 of these were in the pre-implementation phase), precluding statistical analysis on mortality related to the intervention. The RRT averaged 6 to 10 interventions for hyperkalemia monthly (representing 10% of all inpatient K(+) values ≥ 6.3 mEq/L). Mean initial K(+) level triggering the RRT cascade was 6.7 ± 0.3 mEq/L; average time from floor notification of critical K(+) level to bedside RRT arrival was 14.6 ± 12.1 minutes. Over 24 to 36 hours, K(+) declined 1.7 ± 1.1 mEq/L between patients' initial and final K(+) values (P < 0.001).

CONCLUSIONS

Hyperkalemia occurs frequently in inpatient settings. Rapid response team intervention for this condition facilitates timely correction of critical laboratory test results and consistent treatment through use of a standardized protocol. Benefit of the intervention on mortality could not be reliably demonstrated in this study due to event rarity and challenges with case ascertainment. Further research with a prospective, multi-site cluster design using electronic medical records and larger sample sizes could demonstrate which RRT hyperkalemia intervention components warrant widespread adoption.

Evaluation of coma: a critical appraisal of popular scoring systems

Numerous scoring scales have been proposed and validated to evaluate coma for rapid pre-hospital assessment and triage, disease severity, and prognosis for morbidity and mortality. These scoring systems have been predicated on core features that serve as a basis for this review and include ease of use, inter-rater reliability, reproducibility, and predictive value. Here we review the benefits and limitations of the most popular coma scoring systems. The methods include search of Medline, databases, and manual review of article bibliographies. Few of the many available coma scales have gained widespread approval and popularity. The best known and widely accepted scale is the Glasgow Coma Scale (GCS). The Reaction Level Scale (RLS85) has utility and proven benefit, but little acceptance outside of Scandinavia. The newer Full Outline of UnResponsiveness (FOUR) score provides an attractive replacement for all patients with fluctuating levels of consciousness and is gradually gaining wide acceptance.

Clinical emergencies and outcomes in patients admitted to a surgical versus medical service

BACKGROUND

The merit of rapid response systems (RRSs) remains controversial. A tailored approach to specific groups may increase the efficacy of these teams. The purpose of this study was to compare differences in triggers for RRS activation, interventions, and outcomes in patients on medical and surgical services.

METHODS

A retrospective review RRS events was performed. The incidence of out of ICU cardiac arrests and hospital mortality were compared 2 years prior to and following RRS implementation. Call trigger, interventions, and disposition between medical and surgical patients were compared over a 15 month period.

RESULTS

Out of ICU cardiac arrest was significantly more prevalent in the medical group both before and after implementation of RRS. The out of ICU cardiac arrest rate decreased 32% in the surgical group (p=0.05) but hospital mortality did not change. Out of ICU cardiac arrest decreased 40% in the medical group (p<0.001) and hospital mortality decreased 25% (p<0.001) following RRS implementation. There were 1082 RRS activations, 286 surgical and 796 medical. Surgical patients were more likely to have received sedation within 24 h of evaluation (14% vs. 4%, p<0.001). The majority of patients in both cohorts were discharged alive.

CONCLUSION

Implementation of a RRS had greater impact on reduction of out of ICU cardiac arrest and mortality in medical inpatients. Triggers for activation and interventions were similar between groups; however, surgical patients demonstrated substantial risk for decompensation within the first 24 h following operation. More research is needed to evaluate the disproportionate benefit observed between cohorts.

Vasogenic shock physiology

Shock means inadequate tissue perfusion by oxygen-carrying blood. In vasogenic shock, this circulatory failure results from vasodilation and/or vasoplegia. There is vascular hyporeactivity with reduced vascular smooth muscle contraction in response to α1 adrenergic agonists. Considering vasogenic shock, one can understand its utmost importance, not only because of its association with sepsis but also because it can be the common final pathway for long-lasting, severe shock of any cause, even postresuscitation states. The effective management of any patient in shock requires the understanding of its underlying physiology and pathophysiology. Recent studies have provided new insights into vascular physiology by revealing the interaction of rather complicated and multifactorial mechanisms, which have not been fully elucidated yet. Some of these mechanisms, such as the induction of nitric oxide synthases, the activation of adenosine triphosphate-sensitive potassium channels, and vasopressin deficiency, have gained general acceptance and are considered to play an important role in the pathogenesis of vasodilatory shock. The purpose of this review is to provide an update on the pathogenesis of vasogenic shock.

Rapid response team composition effects on outcomes for adult hospitalised patients: A systematic review

BACKGROUND

Utilisation of a rapid response team (RRT) in a hospital setting has been documented in the literature. RRTs were formed to intervene quickly when the hospitalised patient first shows signs of deterioration. The purpose was to prevent failure to rescue, leading to intensive care unit transfers, cardiac arrest and mortality. To date, however, there is a lack of evidence to support the effectiveness of this intervention. The focused question, subsequent systematic review and data analysis are presented.

OBJECTIVE

To synthesise the best available research evidence on the impact of rapid response team composition on cardiopulmonary arrest outside the intensive care unit (ICU), unplanned transfers to ICU, in-hospital mortality, length of hospital stay in hospitalised non-ICU adult medical-surgical patients and staff satisfaction.

SEARCH STRATEGY

Published and unpublished literature were searched. The databases searched for studies from 1989 to 2010 were CINAHL, EMBASE, Google Scholar, Mednar, New York Academy of Medicine, Proquest and PubMed. Reference lists of included studies were hand searched. Initial keywords searched were rapid response team, rapid response system, medical emergency team, medical emergency system and team composition.

INCLUSION CRITERIA

The studies included in the systematic review were randomized controlled trials (RCTs). In absence of sufficient RCTs, quasi-experimental studies, cohort studies, observational and control trials without randomization were included. Types of participants were adults (18 years and older) hospitalised in an acute care setting, not requiring the specialized care and management of an ICU. Hospitalised paediatric patients, ICU patients, hospice or palliative care patients were excluded.

CRITICAL APPRAISAL, DATA COLLECTION AND ANALYSIS

JBI MAStARI Critical Appraisal Tools were used for the methodological assessment of identified studies. Data were collected specifically related to RRT intervention, study methods and design, randomization, length of intervention, data collection points and inclusion criteria. Significant variables of interest included in the data collection were team composition, cardiopulmonary arrest outside the ICU, unplanned transfers to the ICU, in-hospital mortality, length of hospital stay and staff satisfaction. Data were extracted and analysed using the Joanna Briggs Institute Meta Analysis of Statistics Assessment and Review Instrument (JBI-MAStARI). The findings were presented in narrative form as statistical meta-analysis was not possible.

MAIN RESULTS

A total of 26 articles were included. The types of studies included in this systematic review were one cluster randomized control trial and one controlled trial without randomization. The remaining 24 studies were quasi-experimental cohort control design with two being retrospective studies and 22 prospective before-and-after intervention studies. Of those included, 10 were physician led, 13 were critical care registered nurse led and three nurse practitioner led. No association was found between team composition and patient outcomes.

CONCLUSIONS

This systematic review found no correlation between team composition and patient outcomes. Teams that were mature, dedicated, made rounds and required mandatory activation had statistically significant results. These teams were more effective in decreasing cardiopulmonary arrest outside of the ICU, unplanned ICU transfer, in-hospital mortality, length of hospital stay and increased staff satisfaction.

IMPLICATIONS FOR PRACTICE

RRT activation was either mandatory or voluntary. Mandatory activation directed the RRT to be called if specific predetermined criteria were observed. Voluntary activation of the team was at the discretion of the staff regardless of guidelines. In these instances, concerns were reported about initiating "inappropriate" activation. Dedicated RRTs making proactive rounds and educating staff led to improved outcomes and staff satisfaction.

IMPLICATIONS FOR RESEARCH

Short study periods after team implementation may not accurately reflect the effectiveness of the RRT. Evidence points to significant results with team maturation. Further research should be directed toward more rigorous studies on team maturation, mandatory versus voluntary team activations, use of dedicated teams making rounds and staff satisfaction.

Differential involvement of potassium channel subtypes in early and late sepsis-induced hyporesponsiveness to vasoconstrictors

This study investigated the involvement of potassium channel subtypes in the hyporesponsiveness to vasoconstrictors of an experimental model of sepsis [cecal ligation and puncture (CLP)], at 2 time points, namely, 6 and 24 hours after sepsis onset. Wistar rats were submitted to CLP or sham surgery, and 6 and 24 hours later, responses to phenylephrine were obtained before and 30 minutes after injection of potassium channel blockers. The potassium channel blockers used were tetraethylammonium (TEA; a nonselective channel blocker), glibenclamide (GLB; an adenosine triphosphate -dependent channel blocker), 4-aminopyridine (4-AP; a voltage-dependent channel blocker), apamin (APA; a small-conductance calcium-dependent channel blocker), and iberiotoxin (IBTX; a large-conductance calcium-dependent channel blocker). It was found that (1) sepsis caused a severe vascular hyporesponsiveness to phenylephrine both 6 and 24 hours after CLP, (2) TEA partially reversed the hyporesponsiveness 6 hours after CLP and completely restored vascular response to phenylephrine 24 hours after CLP, (3) apamin reversed hyporesponsiveness 6 but not 24 hours after CLP, (4) GLB restored phenylephrine response only 24 hours after CLP, and (5) IBTX and 4-AP were ineffective in all periods studied. Our results suggest that potassium channels are important effectors of sepsis-induced vascular dysfunction in vivo and that different subtypes of potassium channels are involved in early (small-conductance calcium-dependent potassium channels) and late (adenosine triphosphate -dependent potassium channels) hyporesponsiveness to vasoconstrictors caused by sepsis.

2, 4-dinitrophenol poisoning caused by non-oral exposure

2, 4-Dinitrophenol (2, 4-DNP) is widely used in industry, but recently, poisoning through consumption for weight control has been frequently reported. We report the cases of two patients whose deaths were attributed to occupational and non-oral exposure of 2, 4-DNP. They were all poisoned through skin absorption and respiratory tract inhalation; common features were excessive sweating, hyperthermia, tachycardia, clouded consciousness and asystole. Because of the lack of specific early symptoms, effective antidotes and the means of washing the contamination from the skin, their arrival in hospital was delayed and the supportive therapy was ineffectual. Cardiac arrest occurred quickly and unexpected after admission.

Literature review: do rapid response systems reduce the incidence of major adverse events in the deteriorating ward patient?

AIMS

To conduct a literature review that explores the impact of rapid response systems on reducing major adverse events experienced by deteriorating ward patients.

BACKGROUND

Patients located on hospitals wards are frequently older, have multiple co-morbidities and are often at risk of life-threatening clinical deterioration. Rapid response systems have been developed and implemented to provide appropriate and timely intervention to these patients.

DESIGN

A comprehensive review of the literature.

METHODS

This review used the rapid response systems framework recently developed by experts in the area. Medline, CINAHL, Embase and Cochrane databases were searched from January 1995-June 2009. Sixteen papers were selected that most clearly reflected the research aim. Each paper was critically appraised and systematically assessed. Major themes and findings were identified for each of the studies.

RESULTS

The effectiveness of rapid response systems in reducing major adverse events in deteriorating ward patients remains inconclusive. Six studies demonstrated that the introduction of a rapid response systems positively impacted on patient outcomes, but three studies demonstrated no positive impact on patient outcomes. Nursing staff appear reluctant to use rapid response systems; the rationale for this is unclear. However, the continued underuse and inactivation may be one reason why research findings evaluating rapid response systems have been inconclusive.

CONCLUSIONS

 The paper illustrates two important gaps in the literature. First, 'ramp-up' systems have not been subjected to formal evaluation. Second, rapid response systems are under-activated and underused by nursing staff. There is an urgent need to explore the reasons for this and to identify interventions to improve the activation of these systems in an effort to promote safe and effective care to the deteriorating ward patient.

RELEVANCE TO CLINICAL PRACTICE

Rapid response systems are multidimensional models. They are relatively new innovations that have important implications for clinical research and implementation policy. This review contributes to the emerging debate on rapid response systems.

Impact of critical care outreach on hematopoietic stem cell transplant recipients: a cohort study

Serious morbidity and mortality can occur after hematopoietic SCT (HSCT). Critical care outreach (CCO) can provide timely access to intensive care for hospitalized patients in need of urgent stabilization but has not been examined in HSCT. Rapid Assessment of Critical Events (RACE) team was introduced at our centre January 1, 2005. A retrospective cohort study was performed. Patients undergoing HSCT between January 1, 2000 and December 31, 2004 (n=520) formed the 'before' cohort and patients transplanted between January 1, 2005 and December 31, 2007 (n=294) formed the 'after' cohort. Non-relapse mortality at day 100 after transplant was not different in the two cohorts (26 (8.8%) post-RACE vs 53 (10.2%) pre-RACE, P=0.62). The number of failed organs at time of transfer to intensive care unit (ICU) was reduced in the post-RACE cohort (1.9 ± 0.8 vs 2.3 ± 1.0, P=0.04) and the incidence of cardiovascular failure was lower (23.8 vs 43.8%, P=0.04). Other secondary outcomes were not different, including the frequency of ICU admission. RACE may contribute to earlier stabilization during critical illness in patients undergoing HSCT but does not reduce non-relapse mortality. CCO should be studied prospectively in patients undergoing HSCT to better evaluate its role.

Critical care trial design and interpretation: a primer

OBJECTIVE

Better understanding of the pathophysiology of critical illness has led to an increase in clinical trials designed to improve the clinical care and outcomes of patients with life-threatening illness. Knowledge of basic principles of clinical trial design and interpretation will assist the clinician in better applying the results of these studies into clinical practice.

DATA SOURCES

We review selected clinical trials to highlight important design features that will improve understanding of the results of critical care clinical trials designed to improve clinical care of the critically ill.

RESULTS

Trial design features such as patient selection, bias, sample size calculation, selection of subjects and controls, and primary outcome measure may influence the results of a critical care clinical trial designed to test a therapy targeting improved clinical care. In conjunction with trial design knowledge, understanding the size of the anticipated treatment effect, the importance of any clinical end point achieved, and whether patients in the trial are representative of typical patients with the illness will assist the reader in determining whether the results should be applied to specific patients or usual clinical practice.

CONCLUSIONS

Better understanding of important aspects of trial design and interpretation, such as whether patients enrolled in both intervention arms were comparable and whether the primary outcome of the trial is clinically important, will assist the bedside clinician in determining whether to apply the findings from the clinical study into clinical practice.

Vascular hyporesponsiveness to vasopressors in septic shock: from bench to bedside

PURPOSE

To delineate some of the characteristics of septic vascular hypotension, to assess the most commonly cited and reported underlying mechanisms of vascular hyporesponsiveness to vasoconstrictors in sepsis, and to briefly outline current therapeutic strategies and possible future approaches.

METHODS

Source data were obtained from a PubMed search of the medical literature with the following MeSH terms: Muscle, smooth, vascular/physiopathology; hypotension/etiology; shock/physiopathology; vasodilation/physiology; shock/therapy; vasoconstrictor agents.

RESULTS

Nitric oxide (NO) and peroxynitrite are crucial components implicated in vasoplegia and vascular hyporeactivity. Vascular ATP-sensitive and calcium-activated potassium channels are activated during shock and participate in hypotension. In addition, shock state is characterized by inappropriately low plasma glucocorticoid and vasopressin concentrations, a dysfunction and desensitization of alpha-receptors, and an inactivation of catecholamines by oxidation. Numerous other mechanisms have been individualized in animal models, the great majority of which involve NO: MEK1/2-ERK1/2 pathway, H(2)S, hyperglycemia, and cytoskeleton dysregulation associated with decreased actin expression.

CONCLUSIONS

Many therapeutic approaches have proven their efficiency in animal models, especially therapies directed against one particular compound, but have otherwise failed when used in human shock. Nevertheless, high doses of catecholamines, vasopressin and terlipressin, hydrocortisone, activated protein C, and non-specific shock treatment have demonstrated a partial efficiency in reversing sepsis-induced hypotension.

Rapid response team in an academic institution: does it make a difference?

BACKGROUND

Although data remain contradictory, rapid response systems are implemented across US hospitals. We aimed to determine whether implementation of a rapid response team (RRT) in a tertiary academic hospital improved outcomes.

METHODS

Our hospital is a tertiary academic medical center with 24-h in-house resident coverage. We conducted a retrospective cohort study comparing 27 months after implementation of the RRT (April 1, 2006, to June 31, 2008) and 9 months before (January 1, 2005, to September 31, 2005). Outcomes included incidence of codes (cardiac and/or respiratory arrests), outcome of the codes, and overall hospital mortality.

RESULTS

We analyzed 16,244 nonobstetrics hospital admissions and 70,208 patient days in the control period and 45,145 nonobstetrics hospital admissions and 161,097 patient days after the RRT was implemented. The RRT was activated 1,206 times (7.7 calls per 1,000 patient days). There was no difference in the code rate (0.83 vs 0.98 per 1,000 patient days, P = .3). There was a modest but nonsustained improvement in nonobstetrics hospital mortality during the study period (2.40% vs 2.15%; P = .05), which could not be explained by the RRT effect on code rates. The mortality was 2.40% in the control group and 2.06%, 1.94%, and 2.46%, respectively, during the next three consecutive 9-month intervals.

CONCLUSIONS

In our single-institution study involving an academic hospital with 24-h in-house coverage, we found that RRT implementation did not reduce code rates in the 27 months after intervention. Although there was a decrease in overall hospital mortality, this decrease was small, nonsustained, and not explained by the RRT effect on code rates.

Gentamicin-collagen sponge for infection prophylaxis in colorectal surgery

BACKGROUND

Despite the routine use of prophylactic systemic antibiotics, surgical-site infection continues to be associated with significant morbidity and cost after colorectal surgery. The gentamicin-collagen sponge, an implantable topical antibiotic agent, is approved for surgical implantation in 54 countries. Since 1985, more than 1 million patients have been treated with the sponges.

METHODS

In a phase 3 trial, we randomly assigned 602 patients undergoing open or laparoscopically assisted colorectal surgery at 39 U.S. sites to undergo either the insertion of two gentamicin-collagen sponges above the fascia at the time of surgical closure (the sponge group) or no intervention (the control group). All patients received standard care, including prophylactic systemic antibiotics. The primary end point was surgical-site infection occurring within 60 days after surgery, as adjudicated by a clinical-events classification committee that was unaware of the study-group assignments.

RESULTS

The incidence of surgical-site infection was higher in the sponge group (90 of 300 patients [30.0%]) than in the control group (63 of 302 patients [20.9%], P=0.01). Superficial surgical-site infection occurred in 20.3% of patients in the sponge group and 13.6% of patients in the control group (P=0.03), and deep surgical-site infection in 8.3% and 6.0% (P=0.26), respectively. Patients in the sponge group were more likely to visit an emergency room or surgeon's office owing to a wound-related sign or symptom (19.7%, vs. 11.0% in the control group; P=0.004) and to be rehospitalized for surgical-site infection (7.0% vs. 4.3%, P=0.15). The frequency of adverse events did not differ significantly between the two groups.

CONCLUSIONS

Our large, multicenter trial shows that the gentamicin-collagen sponge is not effective at preventing surgical-site infection in patients who undergo colorectal surgery; paradoxically, it appears to result in significantly more surgical-site infections. (Funded by Innocoll Technologies; ClinicalTrials.gov number, NCT00600925.)

Optimizing hemodynamic support in septic shock using central and mixed venous oxygen saturation

Global tissue hypoxia is one of the most important factors in the development of multisystem organ dysfunction. In hemodynamically unstable critically ill patients, central venous oxygen saturation (Scvo(2)) and mixed venous oxygen saturation (Svo(2)) monitoring has been shown to be a better indicator of global tissue hypoxia than vital signs and other clinical parameters alone. Svo(2) is probably more representative of global tissue oxygenation, whereas Scvo(2), is less invasive. Svo(2) and Scvo(2) monitoring can have diagnostic and therapeutic uses in understanding the efficacy of interventions in treating critically ill, hemodynamically unstable patients.

Wire-guided catheter exchange after failed direct laryngoscopy in critically ill adults

STUDY OBJECTIVE

To describe a technique for tracheal intubation after failed direct laryngoscopy using a Laryngeal Mask Airway (LMA) to secure the airway and to establish ventilation, and as a conduit for fiberoptic intubation utilizing a pre-packaged, convenient, and commercially available wire-guided catheter exchange kit.

DESIGN

Retrospective case series.

SETTING

University hospital.

MEASUREMENTS

The cases of 5 critically ill adult patients who required intubation for respiratory failure, and in whom direct laryngoscopy was unsuccessful and unanticipated, were reviewed. Difficult intubation was defined as > or = two attempts by direct laryngoscopy and use of an airway adjunct/alternate airway device, or > or = three attempts by direct laryngoscopy. Occurrence of hypotension, hypoxemia, and the time required to accomplish the intubation were recorded.

MAIN RESULTS

Patients' tracheas were intubated in the emergency department (n = 2), the intensive care unit (n = 2), and the radiology department (n = 1). An Eschmann endotracheal tube (ETT) introducer was used in 4 of the 5 patients, and a GlideScope was used in the fifth patient. After failed direct laryngoscopy, an LMA Classic was inserted to gain an airway, after which a fiberoptic bronchoscope and wire-guided catheter exchange set was used to change the LMA to a conventional ETT. Ventilation was maintained via the LMA with an attached bronchoscope adapter throughout the procedure.

CONCLUSIONS

In all 5 patients, the trachea was successfully intubated within three minutes on the first attempt, using a wire-guided exchange, without hypoxemia or hypotension.

Updating the evidence for the role of corticosteroids in severe sepsis and septic shock: a Bayesian meta-analytic perspective

Introduction

Current low (stress) dose corticosteroid regimens may have therapeutic advantage in severe sepsis and septic shock despite conflicting results from two landmark randomised controlled trials (RCT). We systematically reviewed the efficacy of corticosteroid therapy in severe sepsis and septic shock.

Methods

RCTs were identified (1950-September 2008) by multiple data-base electronic search (MEDLINE via OVID, OVID PreMedline, OVID Embase, Cochrane Central Register of Controlled trials, Cochrane database of systematic reviews, Health Technology Assessment Database and Database of Abstracts of Reviews of Effects) and hand search of references, reviews and scientific society proceedings. Three investigators independently assessed trial inclusion and data extraction into standardised forms; differences resolved by consensus.

Results

Corticosteroid efficacy, compared with control, for hospital-mortality, proportion of patients experiencing shock-resolution, and infective and non-infective complications was assessed using Bayesian random-effects models; expressed as odds ratio (OR, (95% credible-interval)). Bayesian outcome probabilities were calculated as the probability (P) that OR ≥1. Fourteen RCTs were identified. High-dose (>1000 mg hydrocortisone (equivalent) per day) corticosteroid trials were associated with a null (n = 5; OR 0.91(0.31-1.25)) or higher (n = 4, OR 1.46(0.73-2.16), outlier excluded) mortality probability (P = 42.0% and 89.3%, respectively). Low-dose trials (<1000 mg hydrocortisone per day) were associated with a lower (n = 9, OR 0.80(0.40-1.39); n = 8 OR 0.71(0.37-1.10), outlier excluded) mortality probability (20.4% and 5.8%, respectively). OR for shock-resolution was increased in the low dose trials (n = 7; OR 1.20(1.07-4.55); P = 98.2%). Patient responsiveness to corticotrophin stimulation was non-determinant. A high probability of risk-related treatment efficacy (decrease in log-odds mortality with increased control arm risk) was identified by metaregression in the low dose trials (n = 9, slope coefficient -0.49(-1.14, 0.27); P = 92.2%). Odds of complications were not increased with corticosteroids.

Conclusions

Although a null effect for mortality treatment efficacy of low dose corticosteroid therapy in severe sepsis and septic shock was not excluded, there remained a high probability of treatment efficacy, more so with outlier exclusion. Similarly, although a null effect was not excluded, advantageous effects of low dose steroids had a high probability of dependence upon patient underlying risk. Low dose steroid efficacy was not demonstrated in corticotrophin non-responders. Further large-scale trials appear mandated.

International variations in outcomes from sedation protocol research: where are we at and where do we go from here?

In this article, sedation protocol research in the intensive care environment is critically examined, focusing upon the differences in outcomes from research conducted on mechanically ventilated patients in various countries. Limitations of the current research are discussed, with suggestions of how sedation protocol research may be conducted in future. Also, the monitoring of important clinical factors is discussed so that clinicians can assess the impact upon patients of changes to sedation management practices within their own ICU.