[Analysis of response reports of an in-hospital emergency team : Three years experience at a maximum medical care hospital]

BACKGROUND

In-hospital emergencies can lead to unexpected admission to the ICU, cardiac arrest or even death. Therefore, hospitals have to implement an adequate in-hospital emergency management. The results of the deployment of the in-hospital emergency team of a hospital providing maximum medical care will be presented.

PATIENTS AND METHODS

In 2003 the Westpfalz-Klinikum, Kaiserslautern introduced a central emergency team. The data of the emergency teams on alarm calls and the patient records from 2004 to 2007 were evaluated.

RESULTS

There were 241 alarm calls (9 alarm calls/100 beds and year). The mean age of the patients was 67 years and 56% were male. In 79% of all alarm calls the vital functions were compromised and in 37% cardiac arrest had occurred. When the emergency team arrived all cardiac arrest patients had received basic life support, however, no early defibrillation had been applied. On arrival of the emergency team 41% of the patients could be left on-site after emergency treatment, 40% had to be admitted to an intensive care or intermediate care unit and 21% died or were already dead (5 patients). In 27% of all cardiac arrests ventricular fibrillation/pulseless ventricular tachycardia was the first detected sign. Restoration of spontaneous circulation could be established in 53% and 20% of all resuscitated patients could be discharged. Respiratory emergencies (21%) and altered states of consciousness (20%) were other leading causes for calling the emergency team.

CONCLUSIONS

The high proportion of patients in a life-threatening condition and cardiac arrests indicates the necessity for closer patient monitoring, more intensive emergency training including early defibrillation and continuing education of hospital staff in the prevention and early detection of emergencies, in addition to the provision of an emergency team.

Early CPAP prevents evolution of acute lung injury in patients with hematologic malignancy

PURPOSE

Although chemotherapy and transplantation improve outcome of patients with hematological malignancy, complications of these therapies are responsible for a 20-50% mortality rate that increases when respiratory symptoms evolve into acute lung injury (ALI). The aim of this study is to determine the effectiveness of early continuous positive airway pressure (CPAP) delivered in the ward to prevent occurrence of ALI requiring intensive care unit (ICU) admission for mechanical ventilation.

METHODS

Patients with hematological malignancy presenting in the hematological ward with early changes in respiratory variables were randomized to receive oxygen (N = 20) or oxygen plus CPAP (N = 20). Primary outcome variables were need of mechanical ventilation requiring ICU admission, and intubation rate among those patients who required ICU admission.

RESULTS

At randomization, arterial-to-inspiratory O(2) ratio in control and CPAP group was 282 ± 41 and 256 ± 52, respectively. Patients who received CPAP had less need of ICU admission for mechanical ventilation (4 versus 16 patients; P = 0.0002). CPAP reduced the relative risk for developing need of ventilatory support to 0.25 (95% confidence interval: 0.10-0.62). Among patients admitted to ICU, intubation rate was lower in the CPAP than in the control group (2 versus 14 patients; P = 0.0001). CPAP reduced the relative risk for intubation to 0.46 (95% confidence interval: 0.27-0.78).

CONCLUSIONS

This study suggests that early use of CPAP on the hematological ward in patients with early changes in respiratory variables prevents evolution to acute lung injury requiring mechanical ventilation and ICU admission.

Early goal-directed therapy: on terminal life support?

Early goal-directed therapy (EGDT) has become regarded as the standard of care for the management of patients with severe sepsis and septic shock. The elements of EGDT have been bundled together as the "Sepsis Bundle," and compliance with the elements of the bundle is frequently used as an indicator of the quality of care delivered. The major elements of EGDT include fluid resuscitation to achieve a central venous pressure of 8 to 12 cm of water, followed by the transfusion of packed red cells or an inotropic agent to maintain the central venous oxygen saturation higher than 70%. Although the concept of early resuscitation is a scientifically sound concept, we believe that the major elements of the sepsis bundle are fatally flawed.

Cytokines in blood from septic patients interact with surface-immobilized heparin

When passing blood from septic patients through a column packed with surface heparinized beads, we were able to significantly reduce concentrations of the proinflammatory cytokine tumor necrosis factor (TNF)-alpha from initially very high levels. Passage of blood over nonheparinized beads did not affect the TNF levels. Meanwhile, concentrations of the regulated on activation, normal T-cells expressed, and secreted leukocyte activating cytokine (RANTES) remained unchanged following passage through the heparinized column, but rose significantly after passage through a column packed with the nonheparinized control beads. We conclude that surface heparinization may be a useful technique for selectively regulating the levels of heparin-binding cytokines from whole blood. This may have potential implications for the treatment of hyper-inflammatory conditions such as severe sepsis. Our data also suggests that surface activation and its associated inflammatory response may be avoided by using heparinization of the extracorporeal circuit.

Changing cardiac arrest and hospital mortality rates through a medical emergency team takes time and constant review

OBJECTIVE

To determine the long-term impact of a medical emergency team on survival and to assess the utility of administrative data to monitor outcomes.

DESIGN

Prospective study of cardiac arrests and survival. Retrospective study of administrative data.

SETTING

University affiliated tertiary referral hospital in Melbourne, Australia.

PATIENTS

All patients admitted to hospital in three 6-month periods between 2002-2007 (prospective) and 1993-2007 (retrospective).

INTERVENTION

Implementation of a medical emergency team in November 2002.

MEASUREMENTS AND MAIN RESULTS

In the prospective analysis, rates of unexpected cardiac arrest and hospital mortality (referenced to 1000 patient-care days) were measured before (July-August 2002) and after (December 2002-May 2003, December 2004-May 2005, December 2006-May 2007) the introduction of the medical emergency team. Cardiac arrest rates decreased progressively from 0.78 per 1000 (95% confidence interval, 0.50-1.16) to 0.25 per 1000 (95% confidence interval, 0.15-0.39, p < .001), and hospital mortality from 0.58 per 1000 (95% confidence interval, 0.35-0.92) to 0.30 per 1000 (95% confidence interval, 0.20-0.46, p < .05); cardiac arrest rates achieved statistical significance at 2 yrs and hospital mortality at 4 yrs. Using administrative data adjusted for age, sex, case-mix, and comorbidity, hazard ratios for mortality for the three post implementation periods were statistically lower than for the 10 yrs pre implementation (0.85, 0.74, 0.65). The intensity of calling (calls/1000 patient-days) inversely correlated with cardiac arrest rate, unexpected mortality rate, and total hospital mortality rate.

CONCLUSIONS

The introduction of a medical emergency team was associated with a progressive decline of unexpected cardiac arrests within 2 yrs, and of unexpected mortality within 4 yrs. This suggests that changes to organizational practice take time and benefits may not be immediately obvious. Such changes are reflected in total hospital mortality measured from administrative data and make monitoring simpler in the longer term. Finally, efforts to increase calling of emergency teams should reduce cardiac arrests and mortality.

Bundled care for septic shock: an analysis of clinical trials

CONTEXT

Sepsis bundles have been developed to improve patient outcomes by combining component therapies. Valid bundles require effective components with additive benefits. Proponents encourage evaluation of bundles, both as a whole and based on the performance of each component.

OBJECTIVE

Assess the association between outcome and the utilization of component therapies in studies of sepsis bundles.

DATA SOURCE

Database searches (January 1980 to July 2008) of PubMed, Embase, and the Cochrane Library, using the terms sepsis, bundles, guidelines, and early goal directed therapy.

DATA EXTRACTION

Inclusion required comparison of septic adults who received bundled care vs. nonprotocolized care. Survival and use rates for individual interventions were abstracted.

MAIN RESULTS

Eight unblinded trials, one randomized and seven with historical controls, were identified. Sepsis bundles were associated with a consistent (I2 = 0%, p = .87) and significant increase in survival (odds ratio, 1.91; 95% confidence interval, 1.49-2.45; p < .0001). For all studies reporting such data, there were consistent (I2 = 0%, p > or = .64) decreases in time to antibiotics, and increases in the appropriateness of antibiotics (p < or = .0002 for both). In contrast, significant heterogeneity was seen across trials for all other treatments (antibiotic use within a specified time period; administration of fluids, vasopressors, inotropes, and packed red blood cells titrated to hemodynamic goals; corticosteroids and human recombinant activated protein C use) (all I2 > or = 67%, p < .002). Except for antibiotics, sepsis bundle components are still being investigated for efficacy in randomized controlled trials.

CONCLUSION

Bundle use was associated with consistent and significant improvement in survival and antibiotic use. Use of other bundle components changed heterogeneously across studies, making their impact on survival uncertain. However, this analysis should be interpreted cautiously as these studies were unblinded, and only one was randomized.

Differences in cytokine levels due to gender in colorectal cancer patients

INTRODUCTION

Female gender is associated with longer survival after treatment for colorectal cancer (CRC). Reasons behind this phenomenon are not entirely clear. In addition, higher interleukin-6 (IL-6) and interleukin-1 (IL-1) levels have been found to be associated with poorer prognosis in CRC patients. The aim of this study was to investigate if cytokine levels were different in male and female CRC patients.

METHODS

Pre- and post-operative levels of IL-1, interleukin-1 receptor antagonist (IL-1ra), IL-6 and tumour necrosis factor-alpha (TNF-alpha) were measured using standard solid phase sandwich ELISA in 104 consecutive eligible patients undergoing elective resection for CRC.

RESULTS

Seventy (67.3%) participants were male and the mean age of the group was 67.6years (standard deviation 10.4years, range 39-86years). Pre-operative IL-1beta and post-operative IL-6 levels were significantly higher in males compared with females (U=486.5, p=0.03, U=424, p=0.04), values approaching statistical significance were obtained for pre-operative IL-6 (U=508.5, p=0.06) and post-operative IL-1beta (U=448, p=0.07). Differences in the levels of TNF-alpha and IL-1ra were not statistically significant. Multiple regression analysis using TNM stage as a covariate, showed that gender was an independent predictor of post-operative IL-6 levels (p=0.04).

CONCLUSION

IL-1beta and IL-6 levels were significantly higher in men than in women. This provides evidence of a possible link between gender and cytokine levels in patients with colorectal cancer.

Resident and RN perceptions of the impact of a medical emergency team on education and patient safety in an academic medical center

OBJECTIVE

To assess the perceptions of residents and RNs about the effects of a medical emergency team on patient safety and their own educational experiences.

DESIGN

Survey-based study.

SETTING

A single academic medical center.

PARTICIPANTS

In 2007, 1 yr after the introduction of a medical emergency team, a Web-based survey was administered to 141 internal medicine and general surgery residents and 497 RNs in a single academic medical center. Residents' and RNs' beliefs about the effects of the medical emergency team on patient safety and education were measured using 12 Likert scale items. Group differences were assessed using Mann-Whitney U test and Kruskal-Wallis test.

RESULTS

The overall response rate was 79% (67% for residents and 83% for RNs). Residents and RNs agreed that the medical emergency team improved patient safety, but RNs held this belief more strongly than did residents. Residents neither agreed nor disagreed with the notion that the creation of the medical emergency team decreased their opportunities to obtain critical care skills or education, whereas RNs disagreed with this statement. Relative to surgical residents, medical residents were more involved in activation of the medical emergency team and believed more strongly that the team improved patient safety. Residents and RNs who perceived that they were involved in the call activation had more positive attitudes toward the team.

CONCLUSION

Residents and RNs believe that a medical emergency team improves patient safety in the hospital without compromising educational experiences or skills. Frequency of involvement in the events and the decision to activate the team correlated with more positive attitudes.

Improving the effectiveness of physiology record books as a learning tool for first-year medical students in India

In compliance with the Medical Council of India, preclinical medical students maintain a record of their laboratory work in physiology. The physiology record books also contain a set of questions to be answered by the students. Faculty members and students had indicated that responding to these questions did not serve the intended purpose of being an effective learning tool. The purpose of this study was to obtain the views of the medical students and faculty members at our institution concerning the usefulness of responding to the questions and to gather suggestions for possible improvement. Data were collected through focus groups and questionnaires to first-year medical students and faculty members in physiology and were analyzed using qualitative and quantitative methods. The students and faculty members viewed the physiology record books as a potentially useful learning aid, but lack of time led the students to write the answers without understanding the topic rather than generating their own responses to the questions. Faculty members and students recommended that the students should write the responses to the questions on site during the practical classes, using relevant on-site resources and interacting with faculty members. The findings of the present study may be of value to other medical colleges in India and outside India with modifications based on their specific needs to improve the effectiveness of physiology record books as a learning tool.

A systems approach to the early recognition and rapid administration of best practice therapy in sepsis and septic shock

PURPOSE OF REVIEW

The early recognition and treatment of sepsis is paramount to reducing the mortality of this disease. However, unlike trauma, stroke or acute myocardial infarction, the initial signs of sepsis are subtle and easily missed by clinicians. Thus, hospital-based systems are needed to identify and triage patients who might be septic. This review focuses on the early diagnosis of sepsis and the implementation of a systems-based approach to help coordinate the identification and treatment of patients with this disease.

RECENT FINDINGS

Alterations in traditional hemodynamic parameters, such as blood pressure and heart rate, are poor predictors of the presence of septic shock. Other more subtle findings (such as the 10 signs of vitality) are stronger determinants of poor tissue perfusion in a patient who may be septic. Early detection of a patient who is 'in trouble' on the ward by bedside nurses or physicians and activation of a medical emergency team has been shown to improve outcome. By coupling the medical emergency team with early goal-directed therapy, patients with sepsis can be discovered earlier and have therapy instituted within the so-called 'golden hour', first appreciated with trauma care.

SUMMARY

The institution of a rapid response system for the detection and treatment of septic shock requires a multidisciplinary approach. The infrastructure to create such a system must be facilitated by administrators and implemented by front-line healthcare providers. Continuous assessment of the outcome benefit of such a system by a quality assurance team is the final part of a truly integrated approach to sepsis treatment.

The impact of Rapid Response System on delayed emergency team activation patient characteristics and outcomes--a follow-up study

OBJECTIVE

To evaluate the impact of Rapid Response System (RRS) maturation on delayed Medical Emergency Team (MET) activation and patient characteristics and outcomes.

DESIGN

Observational study.

SETTING

Tertiary hospital.

PATIENTS

Recent cohort of 200 patients receiving a MET review and early control cohort of 400 patients receiving a MET review five years earlier at the start of RRS implementation.

MEASUREMENTS AND RESULTS

We obtained information including demographics, clinical triggers for and timing of MET activation in relation to the first documented MET review criterion (activation delay) and patient outcomes. We found that patients in the recent cohort were older, more likely to be surgical and to have Not For Resuscitation (NFR) orders before MET review. Furthermore, fewer patients (22.0% vs. 40.3%, p<0.001) had delayed MET activation. When delayed activation occurred, there was a non-significant difference in its duration (early cohort: 12.0 [IQR 23.0]h vs. recent cohort: 9.0 [IQR 20.5]h, p=0.554). Similarly, unplanned ICU admissions decreased from 31.3% to 17.3% (p<0.001). Delayed MET activation was independently associated with greater risk of unplanned ICU admission and hospital mortality (O.R. 1.79, 95% C.I. 1.33.-2.93, p=0.003 and O.R. 2.18, 95% C.I. 1.42-3.33, p<0.001, respectively). Being part of the recent cohort was independently associated with a decreased risk of delayed activation (O.R. 0.45, 95% C.I. 0.30-0.67, p<0.001) and unplanned ICU admission (O.R. 0.5, 95% C.I. 0.32-0.78, p=0.003).

CONCLUSIONS

Maturation of a RRS is associated with a decrease in the incidence of unplanned ICU admissions and MET activation delay. Assessment of a RRS early in the course of its implementation may underestimate its efficacy.

Year in review 2008: Critical Care--cardiology

We review key research papers in cardiology and intensive care published during 2008 in Critical Care. We quote studies on the same subject published in other journals if appropriate. Papers have been grouped into three categories: (a) cardiovascular biomarkers in critical illness, (b) haemodynamic management of septic shock, and (c) haemodynamic monitoring.

Effectiveness of the Medical Emergency Team: the importance of dose

Up to 17% of hospital admissions are complicated by serious adverse events unrelated to the patients presenting medical condition. Rapid Response Teams (RRTs) review patients during early phase of deterioration to reduce patient morbidity and mortality. However, reports of the efficacy of these teams are varied. The aims of this article were to explore the concept of RRT dose, to assess whether RRT dose improves patient outcomes, and to assess whether there is evidence that inclusion of a physician in the team impacts on the effectiveness of the team. A review of available literature suggested that the method of reporting RRT utilization rate, (RRT dose) is calls per 1,000 admissions. Hospitals with mature RRTs that report improved patient outcome following RRT introduction have a RRT dose between 25.8 and 56.4 calls per 1,000 admissions. Four studies report an association between increasing RRT dose and reduced in-hospital cardiac arrest rates. Another reported that increasing RRT dose reduced in-hospital mortality for surgical but not medical patients. The MERIT study investigators reported a negative relationship between MET-like activity and the incidence of serious adverse events. Fourteen studies reported improved patient outcome in association with the introduction of a RRT, and 13/14 involved a Physician-led MET. These findings suggest that if the RRT is the major method for reviewing serious adverse events, the dose of RRT activation must be sufficient for the frequency and severity of the problem it is intended to treat. If the RRT dose is too low then it is unlikely to improve patient outcomes. Increasing RRT dose appears to be associated with reduction in cardiac arrests. The majority of studies reporting improved patient outcome in association with the introduction of an RRT involve a MET, suggesting that inclusion of a physician in the team is an important determinant of its effectiveness.

Reducing in-hospital cardiac arrests and hospital mortality by introducing a medical emergency team

PURPOSE

To prospectively evaluate the implementation of a rapid response team in the form of a medical emergency team (MET) with regard to cardiac arrests and hospital mortality.

METHODS

Prospective before-and-after trial of implementation of a MET at the Karolinska University Hospital, Stockholm, Sweden. All adult patients, apart from cardiothoracic, admitted to the hospital were regarded as participants in the study. A control period of 5 years and 203,892 patients preceded the 2-year intervention period of 73,825 patients.

MAIN RESULTS

Number of MET calls was 9.3 per 1,000 hospital admissions. Cardiac arrests per 1,000 admissions decreased from 1.12 to 0.83, OR 0.74 (95% CI 0.55-0.98, p = 0.035). Adjusted for age, sex, hospital length of stay, acute/elective admission as well as co-morbidities, MET implementation was associated with a reduction in total hospital mortality by 10%, OR 0.90 (95% CI 0.84-0.97), p = 0.003. Hospital mortality was also reduced for medical patients by 12%, OR 0.88 (95% CI 0.81-0.96, p = 0.002) and for surgical patients not operated upon by 28%, OR 0.72 (95% CI 0.56-0.92, p = 0.008). FOR PATIENTS FULFILLING THE MET CRITERIA: Thirty-day mortality pre-MET was 25% versus 7.9% following MET compared with historical controls. Similarly, 180-day mortality was 37.5% versus 15.8%, respectively.

CONCLUSIONS

Implementing the MET team was associated with significant improvement in both cardiac arrest rate and overall adjusted hospital mortality. Significant reductions in hospital mortality for un-operated surgical patients as well as for medical patients were also seen. Thus, introduction of the MET seemed to improve outcome for hospitalized patients.

Abnormal activation of potassium channels in aortic smooth muscle of rats with peritonitis-induced septic shock

This study was conducted to examine the role of membrane hyperpolarization in mediating vascular hyporeactivity induced by cecal ligation and puncture (CLP) in endothelial-denuded strips of rat thoracic aorta ex vivo. The CLP for 18 h elicited a significant fall of blood pressure and a severe vascular hyporeactivity to norepinephrine as seen in severe sepsis. At the end of the in vivo experiments, thoracic aortas were removed from both CLP-treated and control rats. After removal of the endothelium, aortic segments were mounted in myographs for the recording of isometric tension and smooth muscle membrane potential. The membrane potential recording showed that a hyperpolarization was observed in the CLP-treated rats when compared with the control rats. This hyperpolarization was reversed by iberiotoxin (a large-conductance Ca2+-activated K+ channel blocker), 4-aminopyridine (a voltage-dependent K+ channel blocker), barium (an inward rectifier K+ channels blocker), N-(1-adamantyl)-N'-cyclohexyl-4-morpholinecarboxamidine hydrochloride (a pore-forming blocker of adenosine triphosphate (ATP)-sensitive K+ channels [KATP]), or methylene blue (a nonspecific guanylyl cyclase [GC] inhibitor). However, this hyperpolarization was not significantly affected by apamin (a small-conductance Ca2+-activated K+ channel blocker), glibenclamide (a sulfonylurea blocker of KATP), N(omega)-nitro-L-arginine methyl ester (a NOS inhibitor), or 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (an NO-sensitive GC inhibitor). In addition, the basal tension of the tissues obtained from CLP rats was increased simultaneously, whereas membrane potential was reversed. In contrast, none of these inhibitors had significant effects on the membrane potential or the basal tension in control tissues. Thus, we provide electrophysiological and functional evidence demonstrating that an abnormal activation of K+ channels in vascular smooth muscle in animals with septic shock induced by CLP. Our observations suggest that the activation of large conductance Ca2+-activated K+ channels, voltage-dependent K+ channels, inward rectifier K+ channels, and KATP channels, but not small conductance Ca2+-activated K+ channels, contributes to CLP-induced vascular hyporeactivity. Furthermore, the hyperpolarization in septic shock induced by CLP is likely via non-NO-sensitive GC pathway.

Enhanced end-of-life care associated with deploying a rapid response team: a pilot study

HYPOTHESIS

Institution of a rapid response team (RRT) improves patients' quality of death (QOD).

SETTING

A 425-bed community teaching hospital.

PATIENTS

: All medical-surgical patients whose end-of-life care was initiated on the hospital wards during the 8 months before (pre-RRT) and after (post-RRT) actuation.

STUDY DESIGN

Retrospective cohort study.

METHODS

Medical records of all patients were reviewed using a uniform data abstraction tool. Demographic information, diagnoses, physiologic and laboratory data, and outcomes were recorded.

RESULTS

A total of 197 patients died in both the pre-RRT and post-RRT periods. There were no differences in age, sex, advance directives, ethnicity, or religion between groups. Restorative outcomes, including in-hospital mortality (27 vs. 30/1000 admissions), unexpected transfers to intensive care (17 vs. 19/1000 admissions) and cardiac arrests (3 vs. 2.5/1000 admissions) were similar during the 2 periods. Outcomes, including formal comfort care only orders (68 vs. 46%), administration of opioids (68 vs. 43%), pain scores (3.0 +/- 3.5 vs. 3.7 +/- 3.2), patient distress (26 vs. 62%), and chaplain visits (72 vs. 60%), were significantly better in the post-RRT period compared to the pre-RRT period (all P < 0.05). During the post-RRT period, 61 patients died with RRT care and 136 died without RRT care. End-of-life care outcomes were similar for these groups except more RRT patients had chaplain visits proximate to their deaths (80% vs. 68%; P = 0.0001).

CONCLUSIONS

Institution of an RRT in our hospital had negligible impact on outcomes of patients whose goal was restorative care. Deployment of the RRT was associated with generally improved end-of-life pain management and psychosocial care.

Venous oxygen saturation and lactate gradient from superior vena cava to pulmonary artery in patients with septic shock

Monitoring of central venous oxygen saturation (ScvO2) is considered comparable with mixed venous oxygen saturation (SvO2) in the initial resuscitation phase of septic shock. Our aim was to assess their agreement in septic shock in the intensive care unit setting and the effect of a potential difference in a computed parameter, namely, oxygen consumption (VO2). In addition, we sought for a central venous to pulmonary artery (PA) lactate gradient. We enrolled 37 patients with septic shock who were receiving noradrenaline infusions, and their attending physicians had placed a PA catheter for fluid management. Blood samples were drawn in succession from the superior vena cava, right atrium (RA), right ventricle, and PA. Hemodynamic and treatment parameters were monitored, and data were compared by correlation and Bland-Altman analysis. Mixed venous oxygen saturation was lower than ScvO2 (70.2% +/- 11.4% vs. 78.6% +/- 10.2%; P < 0.001), with a bias of -8.45% and 95% limits of agreement ranging from -20.23% to 3.33%. This difference correlated significantly to the noradrenaline infusion rate and the oxygen consumption and extraction ratio. These lower SvO2 values resulted in computed VO2v higher than the VO2cv (P < 0.001), with a bias of 104.97 mL min(-1) and 95% limits of agreement from -4.12 to 214.07 mL min(-1). Finally, lactate concentration was higher in the superior vena cava and RA than in the PA (2.42 +/- 3.15 and 2.35 +/- 3.16 vs. 2.17 +/- 3.19 mM; P < 0.01 for both comparisons). Thus, our data suggest that ScvO2 and SvO2 are not equivalent in intensive care unit patients with septic shock. Additionally, the substitution of ScvO2 for SvO2 in the calculation of VO2 produces unacceptably large errors. Finally, the decrease in lactate between RA and PA may support the hypothesis that the mixing of RA and coronary sinus blood is at least partially responsible for the difference between ScvO2 and SvO2.

Developing and evaluating a trigger response system

Based on its experience in implementing a rapid response system, a Level III trauma medical center recommends that other organizations (1) involve key stakeholders in the development process, (2) develop an awareness campaign, (3) hardwire the trigger response process, (4) develop quality success measures and metrics, and (5) implement a pilot and make data-driven changes accordingly.

Central venous oxygen saturation and emergency intubation--another piece in the puzzle?

A recent multicentre observational study examined the effect of emergency intubation on central venous oxygen saturation (SCVo2) in critically ill patients. The main finding was that SCVo2 significantly increases 15 minutes after emergency intubation and institution of mechanical ventilation with 100% oxygen, especially in those patients with pre-intubation SCVo2 values <70%, regardless of whether these patients suffered from severe sepsis. However, in only one-quarter of this subgroup was the SCVo2 normalized to > or =70% solely by this intervention. In contrast, in patients with pre-intubation SCVo2 > or =70%, the SCVo2 failed to increase after intubation. A rise in SCVo2 can be expected when whole body oxygen extraction remains unchanged after intubation and ventilation with pure oxygen.

Variable effects of inhibiting iNOS and closing the vascular ATP-sensitive potassium channel (via its pore-forming and sulfonylurea receptor subunits) in endotoxic shock

Excess production of NO and activation of vascular ATP-sensitive potassium (K(ATP)) channels are implicated in the hypotension and vascular hyporeactivity associated with endotoxic shock. Using a fluid-resuscitated endotoxic rat model, we compared the cardiovascular effects of an iNOS inhibitor and two distinct inhibitors of the K(ATP) channel. Endotoxin (LPS) was administered to anesthetized, spontaneously breathing, fluid-resuscitated adult male Wistar rats, in which MAP, aortic and renal blood flow, and hepatic microvascular oxygenation were monitored continuously. At 120 min, the iNOS inhibitor, GW273629, and the K(ATP)-channel inhibitors, PNU-37883A and glyburide, were administered separately, and their effects on hemodynamics and oxygenation were examined. We found that GW273629 increased MAP over and above the pressor effect achieved in sham animals. Inhibiting K(ATP) channels via the pore-forming subunit (PNU-37883A and high-dose glyburide) produced significant pressor effects, whereas inhibiting the sulfonylurea receptor with low-dose glyburide was ineffective. No agent reversed the fall in aortic or renal blood flow, the fall in hepatic microvascular oxygenation, or the metabolic acidosis that occurred in LPS-treated animals. We conclude that inhibition of the K(ATP) channel via the pore-forming, but not the sulfonylurea receptor subunit, increases blood pressure in a short-term endotoxic model. However, this was not accompanied by any improvement in macrocirculatory or microcirculatory organ blood flow nor reversal of metabolic acidosis. It therefore remains uncertain whether the iNOS pathway or the K(ATP) channel represents a potential target for drug development in the treatment of endotoxic shock.

Impact of emergency intubation on central venous oxygen saturation in critically ill patients: a multicenter observational study

INTRODUCTION

Central venous oxygen saturation (ScvO2) has emerged as an important resuscitation goal for critically ill patients. Nevertheless, growing concerns about its limitations as a perfusion parameter have been expressed recently, including the uncommon finding of low ScvO2 values in patients in the intensive care unit (ICU). Emergency intubation may induce strong and eventually divergent effects on the physiologic determinants of oxygen transport (DO2) and oxygen consumption (VO2) and, thus, on ScvO2. Therefore, we conducted a study to determine the impact of emergency intubation on ScvO2.

METHODS

In this prospective multicenter observational study, we included 103 septic and non-septic patients with a central venous catheter in place and in whom emergency intubation was required. A common intubation protocol was used and we evaluated several parameters including ScvO2 before and 15 minutes after emergency intubation. Statistical analysis included chi-square test and t test.

RESULTS

ScvO2 increased from 61.8 +/- 12.6% to 68.9 +/- 12.2%, with no difference between septic and non-septic patients. ScvO2 increased in 84 patients (81.6%) without correlation to changes in arterial oxygen saturation (SaO2). Seventy eight (75.7%) patients were intubated with ScvO2 less than 70% and 21 (26.9%) normalized the parameter after the intervention. Only patients with pre-intubation ScvO2 more than 70% failed to increase the parameter after intubation.

CONCLUSIONS

ScvO2 increases significantly in response to emergency intubation in the majority of septic and non-septic patients. When interpreting ScvO2 during early resuscitation, it is crucial to consider whether the patient has been recently intubated or is spontaneously breathing.

Reduction of hospital mortality and of preventable cardiac arrest and death on introduction of a pediatric medical emergency team

OBJECTIVE

To determine the effect of a medical emergency team (MET) on the incidence of unexpected cardiac arrest and death.

DESIGN

Comparison of retrospective data (pre-MET) before introduction of MET with prospective data after introduction of MET system (post-MET).

SETTING

Tertiary care pediatric hospital.

PATIENTS

A total of 104,780 admissions during a 41-month period pre-MET; 138,424 admissions during 48 months post-MET.

INTERVENTIONS

Introduction of a MET.

RESULTS

Total hospital deaths decreased from 4.38 to 2.87/ 1000 admissions (risk ratio 0.65, 95% confidence interval [CI] 0.57-0.75, p < 0.0001). Ward unexpected death decreased from 13 (0.12/1000) to 6 (0.04/1000) (risk ratio 0.35, 95% CI 0.13- 0.92, p = 0.03) but unexpected cardiac arrests did not change from 0.19/1000 to 0.17/1000 (risk ratio 0.91, 95% CI 0.50 -1.64, p = 0.75). Thirty-four hospital deaths, including three unexpected deaths (1 out of 72 MET calls), were prevented each year of MET operation. Preventable cardiac arrest (children whose symptoms or signs fulfilled MET calling criteria) decreased from 17 (0.16/ 1000) to 10 (0.07/1000) (risk ratio 0.45, 95% CI 0.20-0.97, p = 0.04) and in whom death decreased from 12 to 2 (0.11/1000 to 0.01/1000) (risk ratio 0.13, 95% CI 0.03-0.56, p = 0.001). Nonpreventable cardiac arrest (children whose symptoms or signs did not fulfill MET calling criteria) increased from 3 to 14 (0.03/1000 to 0.10/1000, p = 0.03) but death did not increase. Survival from cardiac arrest increased from 7 of 20 patients to 17 of 23 (risk ratio 2.11, 95% CI 1.11- 4.02, p = 0.01). Annual calls for urgent assistance were 202 in the post-MET era and 46 during the pre-MET era (ratio 4.4:1).

CONCLUSIONS

Introduction of a MET was associated with reduction of total hospital death and reduction of preventable cardiac arrest and death with increased survival in wards of a pediatric hospital. MET calling criteria identified some but not all children at risk of unexpected cardiac arrest and death.

Gastric tonometry versus cardiac index as resuscitation goals in septic shock: a multicenter, randomized, controlled trial

INTRODUCTION

Resuscitation goals for septic shock remain controversial. Despite the normalization of systemic hemodynamic variables, tissue hypoperfusion can still persist. Indeed, lactate or oxygen venous saturation may be difficult to interpret. Our hypothesis was that a gastric intramucosal pH-guided resuscitation protocol might improve the outcome of septic shock compared with a standard approach aimed at normalizing systemic parameters such as cardiac index (CI).

METHODS

The 130 septic-shock patients were randomized to two different resuscitation goals: CI >or= 3.0 L/min/m2 (CI group: 66 patients) or intramucosal pH (pHi) >or= 7.32 (pHi group: 64 patients). After correcting basic physiologic parameters, additional resuscitation consisting of more fluids and dobutamine was started if specific goals for each group had not been reached. Several clinical data were registered at baseline and during evolution. Hemodynamic data and pHi values were registered every 6 hours during the protocol. Primary end point was 28 days' mortality.

RESULTS

Both groups were comparable at baseline. The most frequent sources of infection were abdominal sepsis and pneumonia. Twenty-eight day mortality (30.3 vs. 28.1%), peak Therapeutic Intervention Scoring System scores (32.6 +/- 6.5 vs. 33.2 +/- 4.7) and ICU length of stay (12.6 +/- 8.2 vs. 16 +/- 12.4 days) were comparable. A higher proportion of patients exhibited values below the specific target at baseline in the pHi group compared with the CI group (50% vs. 10.9%; P < 0.001). Of 32 patients with a pHi < 7.32 at baseline, only 7 (22%) normalized this parameter after resuscitation. Areas under the receiver operator characteristic curves to predict mortality at baseline, and at 24 and 48 hours were 0.55, 0.61, and 0.47, and 0.70, 0.90, and 0.75, for CI and pHi, respectively.

CONCLUSIONS

Our study failed to demonstrate any survival benefit of using pHi compared with CI as resuscitation goal in septic-shock patients. Nevertheless, a normalization of pHi within 24 hours of resuscitation is a strong signal of therapeutic success, and in contrast, a persistent low pHi despite treatment is associated with a very bad prognosis in septic-shock patients.

Recent advances in genetic predisposition to clinical acute lung injury

It has been well established that acute lung injury (ALI), and the more severe presentation of acute respiratory distress syndrome (ARDS), constitute complex traits characterized by a multigenic and multifactorial etiology. Identification and validation of genetic variants contributing to disease susceptibility and severity has been hampered by the profound heterogeneity of the clinical phenotype and the role of environmental factors, which includes treatment, on outcome. The critical nature of ALI and ARDS, compounded by the impact of phenotypic heterogeneity, has rendered the amassing of sufficiently powered studies especially challenging. Nevertheless, progress has been made in the identification of genetic variants in select candidate genes, which has enhanced our understanding of the specific pathways involved in disease manifestation. Identification of novel candidate genes for which genetic association studies have confirmed a role in disease has been greatly aided by the powerful tool of high-throughput expression profiling. This article will review these studies to date, summarizing candidate genes associated with ALI and ARDS, acknowledging those that have been replicated in independent populations, with a special focus on the specific pathways for which candidate genes identified so far can be clustered.

Nitric oxide and vascular reactivity in sepsis

Sepsis and septic shock are major causes of morbidity and mortality in critically ill patients. Sepsis and septic shock induce a profound fall in the peripheral vascular tone. NO has been implicated as a key player in vascular changes of sepsis and septic shock. In this brief review, two points are focused in greater detail: first, the involvement of guanylate cyclase and potassium channels in NO vascular effects in sepsis; second, the role played by NO and its two effectors in the long-lasting modifications of vascular reactivity in sepsis. Some recent developments in the area are reviewed.

[Medical emergency teams: current situation and perspectives of preventive in-hospital intensive care medicine]

Severe clinical incidents occur in up to 10% of all non-intensive care unit (ICU) patients, which have an estimated mortality of 5-8%. As in the prehospital setting, early clinical warning signs can be identified in the majority of cases. Studies suggest that introduction of an in-hospital medical emergency team (MET) which responds to objective criteria of physiological deterioration, may effectively reduce the incidence of in-hospital cardiac arrests as well as unanticipated or readmissions to the ICU. According to this concept, METs would evaluate and treat non-ICU patients at risk at an early stage before a potentially fatal deterioration of cardiorespiratory parameters occurs. This article reviews available data on preventive in-hospital intensive care medicine and reflects on the circumstances for an implementation of METs in Germany, Austria and Switzerland.

Pediatric cardiopulmonary resuscitation: advances in science, techniques, and outcomes

More than 25% of children survive to hospital discharge after in-hospital cardiac arrests, and 5% to 10% survive after out-of-hospital cardiac arrests. This review of pediatric cardiopulmonary resuscitation addresses the epidemiology of pediatric cardiac arrests, mechanisms of coronary blood flow during cardiopulmonary resuscitation, the 4 phases of cardiac arrest resuscitation, appropriate interventions during each phase, special resuscitation circumstances, extracorporeal membrane oxygenation cardiopulmonary resuscitation, and quality of cardiopulmonary resuscitation. The key elements of pathophysiology that impact and match the timing, intensity, duration, and variability of the hypoxic-ischemic insult to evidence-based interventions are reviewed. Exciting discoveries in basic and applied-science laboratories are now relevant for specific subpopulations of pediatric cardiac arrest victims and circumstances (eg, ventricular fibrillation, neonates, congenital heart disease, extracorporeal cardiopulmonary resuscitation). Improving the quality of interventions is increasingly recognized as a key factor for improving outcomes. Evolving training strategies include simulation training, just-in-time and just-in-place training, and crisis-team training. The difficult issue of when to discontinue resuscitative efforts is addressed. Outcomes from pediatric cardiac arrests are improving. Advances in resuscitation science and state-of-the-art implementation techniques provide the opportunity for further improvement in outcomes among children after cardiac arrest.

Year in review 2007: Critical Care--cardiology

This review summarises key research papers in the fields of cardiology and intensive care published during 2007 in Critical Care. To create a context and for comparison with the papers described in the review, we cite studies on the same subject published in other journals. The papers have been grouped into four categories: venous oximetry, cardiac surgery, perioperative fluid optimisation, and haemodynamic monitoring.

Bench-to-bedside review: the initial hemodynamic resuscitation of the septic patient according to Surviving Sepsis Campaign guidelines--does one size fit all?

The Surviving Sepsis Campaign guidelines for the management of severe sepsis and septic shock recommend that the initial hemodynamic resuscitation be done according to the protocol used by Rivers and colleagues in their well-known early goal-directed therapy (EGDT) study. However, it may well be that their patients were much sicker on admission than many other septic patients. Compared with other populations of septic patients, the patients of Rivers and colleagues had a higher incidence of severe comorbidities, a more severe hemodynamic status on admission (excessively low central venous oxygen saturation [ScvO₂], low central venous pressure [CVP], and high lactate), and higher mortality rates. Therefore, it may well be that these patients arrived to the hospital in late untreated hypovolemic sepsis, which may have been due, in part at least, to low socioeconomic status and reduced access to health care. The EGDT protocol uses target values for CVP and ScvO₂ to guide hemodynamic management. However, filling pressures do not reliably predict the response to fluid administration, while the ScvO₂ of septic patients is characteristically high due to decreased oxygen extraction. For all these reasons, it seems that the hemodynamic component of the Surviving Sepsis Campaign guidelines cannot be applied to all septic patients, particularly those who develop sepsis during their hospital stay.

Revitalizing an established rapid response team

It is estimated that only 17% of patients survive an in-hospital cardiac arrest. Yet, more lives could be saved if the early signs of clinical deterioration were detected and promptly addressed on a consistent basis. Current evidence suggests that the creation and implementation of a rapid response team can have a positive effect on mortality and morbidity. However, to achieve these results, bedside caregivers must have access to a highly functioning, efficient team with whom they consult regularly in appropriate patient care situations. This article describes one hospital's efforts to rejuvenate its team to achieve the best possible outcomes for its patients and staff.

Outreach in obstetric critical care

The present chapter considers the evolving role of critical care outreach in the general hospital setting and applied to obstetric patients, the mechanics of transferring critically ill obstetric patients to critical care and radiology areas, the scoring systems in use in critical care, and the difficulties in applying these scoring systems to obstetric patients.

Medical emergency and rapid response teams

Hospitals that care for children are establishing medical emergency or rapid response teams as system solutions for preventing unexpected but foreseeable respiratory and cardiac arrest on inpatient units. Typically, an experienced team of doctors and nurses responds quickly to a direct request by any level of staff or even a parent for assistance with a child whose physiologic parameters meet predetermined criteria or whose condition causes concern to them. Several pediatric studies comparing outcomes before and after introduction of these rapid response systems reported reductions in rates of respiratory or cardiac arrest and death but no prospective study has compared pediatric hospitals that have implemented rapid response teams to hospitals that have not.

A prospective study of factors influencing the outcome of patients after a Medical Emergency Team review

OBJECTIVE

To identify factors that predict outcome in patients receiving a Medical Emergency Team review.

DESIGN

Prospective observational study.

SETTING

Tertiary hospital.

PATIENTS

Cohort of 228 patients receiving one or more Medical Emergency Team reviews during daytime hours over a 1-year-period. Control cohort of all patients (n = 900) receiving a Medical Emergency Team review in the same period.

MEASUREMENTS AND RESULTS

We prospectively collected information from patients receiving a Medical Emergency Team review during daytime hours from Monday to Friday (audit group) including the clinical cause of deterioration and timing of call in relation to the first documented Medical Emergency Team call criterion (activation delay). We also collected information from the hospital Medical Emergency Team database regarding all patients visited by the Medical Emergency Team during the same period (complete cohort). Audit group patients had several similar characteristics to complete cohort patients but were less likely to be not-for-resuscitation before Medical Emergency Team review and more likely to receive a Medical Emergency Team review because of hypotension, change in neurological status and oliguria. Delayed Medical Emergency Team activation and not-for resuscitation orders were the only factors to show an independent statistical association with mortality (OR 2.53, 95% CI: 1.2-5.31, P = 0.01 and OR 5.63, 95% CI: 2.81-11.28, P < 0.01, respectively).

CONCLUSION

Delayed Medical Emergency Team activation and NFR orders are the strongest independent predictors of mortality in patients receiving a Medical Emergency Team review. Avoidance of delayed Medical Emergency Team activation should be a priority for hospitals operating rapid response systems.

The impact of the introduction of critical care outreach services in England: a multicentre interrupted time-series analysis

Introduction

Critical care outreach services (CCOS) have been widely introduced in England with little rigorous evaluation. We undertook a multicentre interrupted time-series analysis of the impact of CCOS, as characterised by the case mix, outcome and activity of admissions to adult, general critical care units in England.

Methods

Data from the Case Mix Programme Database (CMPD) were linked with the results of a survey on the evolution of CCOS in England. Over 350,000 admissions to 172 units between 1996 and 2004 were extracted from the CMPD. The start date of CCOS, activities performed, coverage and staffing were identified from survey data and other sources. Individual patient-level data in the CMPD were collapsed into a monthly time series for each unit (panel data). Population-averaged panel-data models were fitted using a generalised estimating equation approach. Various potential outcomes reflecting possible objectives of the CCOS were investigated in three subgroups of admissions: all admissions to the unit, admissions from the ward, and unit survivors discharged to the ward. The primary comparison was between periods when a formal CCOS was and was not present. Secondary analyses considered specific CCOS activities, coverage and staffing.

Results

In all, 108 units were included in the analysis, of which 79 had formal CCOS starting between 1996 and 2004. For admissions from the ward, CCOS were associated with significant decreases in the proportion of admissions receiving cardiopulmonary resuscitation before admission (odds ratio 0.84, 95% confidence interval 0.73 to 0.96), admission out of hours (odds ratio 0.91, 0.84 to 0.97) and mean Intensive Care National Audit & Research Centre physiology score (decrease in mean 1.22, 0.31 to 2.12). There was no significant change in unit mortality (odds ratio 0.97, 0.87 to 1.08) and no significant, sustained effects on outcomes for unit survivors discharged alive to the ward.

Conclusion

The observational nature of the study limits its ability to infer causality. Although associations were observed with characteristics of patients admitted to critical care units, there was no clear evidence that CCOS have a big impact on the outcomes of these patients, or for characteristics of what should form the optimal CCOS.

Inhibition of potassium channels in critical illness

PURPOSE OF REVIEW

The development of refractory arterial hypotension represents a significant problem in the treatment of critically ill patients, especially during sepsis. Increased activation of ATP-sensitive potassium channels in vascular smooth muscle cells is critically implicated in the pathophysiology of sepsis-induced vasodilation and vascular hyporesponsiveness to catecholamines. Pharmacological blockade of ATP-sensitive potassium channels has been proposed as a goal-directed therapeutic approach to stabilize hemodynamics in septic patients.

RECENT FINDINGS

In different animal models of sepsis, ATP-sensitive potassium channel inhibition with intravenously infused sulfonylureas effectively reversed sepsis-induced systemic vasodilation and hypotension. Two recent clinical trials, however, failed to demonstrate beneficial effects of enterally administered glibenclamide on norepinephrine requirements and blood pressure in septic shock patients. Relevant problems related to ATP-sensitive potassium channel blockade with sulfonylureas in human septic shock include the route of administration (enteral versus intravenous) and the dose itself (benefit-risk relationship). In addition, significant adverse events may result from unspecific inhibition of nonvascular ATP-sensitive potassium channels.

SUMMARY

Inhibition of ATP-sensitive potassium channels remains an attractive option to treat excessive vasodilation in the presence of systemic inflammation. Before this knowledge can be translated into clinical practice, however, future research is needed to define the role of ATP-sensitive potassium channels in critical illness and their specific inhibition in different tissues in more detail.