The use of maximum SOFA score to quantify organ dysfunction/failure in intensive care. Results of a prospective, multicentre study. Working Group on Sepsis related Problems of the ESICM

Modified score for disseminated intravascular coagulation in the critically ill

OBJECTIVE

To assess the value of the diagnosis of overt disseminated intravascular coagulation (DIC) according to the International Society on Thrombosis and Haemostasis (ISTH) criteria and that of the parameters included in the ISTH score for overt DIC in predicting day 28 mortality in intensive care patients. Also, to assess the value of the components of the score in the diagnosis of overt DIC.

DESIGN AND SETTING

Retrospective clinical study in a university hospital intensive care unit.

PATIENTS AND PARTICIPANTS

494 consecutive patients admitted in the ICU between January 2002 and October 2003.

MEASUREMENTS AND RESULTS

Clinical and laboratory data, including hemostatic parameters, were collected from computerized databases and patient files. Altogether 19% (95/494) of the patients fulfilled the criteria for overt DIC. Their day 28 mortality rate was higher than that of patients without overt DIC (40% vs. 16%). The lowest platelet count (area under curve, AUC, 0.910), highest plasma D-dimer (AUC 0.846), lowest antithrombin (AUC 0.823), and Owren-type prothrombin time activity (AUC 0.797) discriminated well the patients with and without overt DIC, whereas plasma fibrinogen (AUC 0.690) had poor discriminative power. No patient with the diagnosis of overt DIC had decreased plasma fibrinogen. Day-1 SOFA and APACHE II score, the first CRP measurement, and the lowest antithrombin were independent predictors of day 28 mortality.

CONCLUSIONS

The diagnosis of overt DIC was not an independent predictor of day 28 mortality. In ICU patients plasma antithrombin seems a promising candidate in the panel of indicators for overt DIC whereas the value of plasma fibrinogen is in doubt.

Multicenter study of the multiple organ dysfunction syndrome in intensive care units: the usefulness of Sequential Organ Failure Assessment scores in decision making

OBJECTIVE

This study examined the incidence and mortality of multiple organ dysfunction syndrome (MODS) in intensive care units, evaluated the limitation of life support in these patients, and determined whether daily measurement of the Sequential Organ Failure Assessment (SOFA) is useful for decision making.

DESIGN AND SETTING

Prospective, observational study in 79 intensive care units.

PATIENTS AND PARTICIPANTS

Of the 7,615 patients admitted during a 2-month period we found 1,340 patients to have MODS.

MEASUREMENTS AND RESULTS

We recorded mortality and length of stay in the intensive care unit and the hospital and the maximum and minimum total SOFA scores during MODS. Limitation of life support in MODS patients was also evaluated. Stepwise logistic regression was used to determine the factors predicting mortality. The in-hospital mortality rate in patients with MODS was 44.6%, and some type of limitation of life support was applied in 70.6% of the patients who died. The predictive model maximizing specificity included the following variables: maximum SOFA score, minimum SOFA score, trend of the SOFA for 5 consecutive days, and age over 60 years. The model diagnostic yield was: specificity 100%, sensitivity 7.2%, positive predictive value 100%, and negative predictive value 57.3%; the area under the receiver operating characteristic curve was 0.807.

CONCLUSIONS

This model showed that in our population with MODS those older than 60 years and with SOFA score higher than 9 for at least 5 days were unlikely to survive.

Severe acute pancreatitis: case-oriented discussion of interdisciplinary management

The clinical course of an episode of acute pancreatitis varies from a mild, transitory illness to a severe often necrotizing form with distant organ failure and a mortality rate of 20-40%. Patients with severe pancreatitis, representing about 15-20% of all patients with acute pancreatitis, need to be identified as early as possible after onset of symptoms allowing starting intensive care treatment early in the disease process. An episode of severe acute pancreatitis progresses in two phases. The first 10-14 days are characterized by a systemic inflammatory response syndrome maintained by the release of various inflammatory mediators. The second phase, beginning about 10-14 days after the onset of the disease is dominated by sepsis-related morbidity due to infected peripancreatic and pancreatic necrosis. This state is associated with septic multiple organ systemic failure. The importance of infection on the outcome of necrotizing pancreatitis has been clearly delineated and the pre-emptive use of broad-spectrum antibiotics that achieve effective tissue concentrations is considered standard management of patients with severe necrotizing pancreatitis, especially if associated with organ failure or extended necrosis. Patients with infected necrosis should undergo a surgical intervention. The standard open technique consisting of an organ preserving necrosectomy followed by a postoperative concept of lavage and/or drainage to evacuate necrotic debris occurring during the further course has recently been challenged by various minimally invasive approaches.

Risk factors for critical illness polyneuromyopathy

Although numerous clinical, laboratory, and pharmacological variables have been reported as significant risk factors for critical illness polyneuromyopathy (CIPM), there is still no consensus on the aetiology of this condition. Objectives of the study were to assess the clinical and electrophysiological incidence and risk factors for CIPM.A cohort of critically ill patients was observed prospectively for a one-month period and the association between neuromuscular involvement and various potential risk factors was evaluated. Sixty one critically ill patients completed the follow-up (30 women, 31 men, median age 59 years).CIPM development was detected clinically in 17 patients (27.9 %) and electrophysiologically in 35 patients (57.4 %). CIPM was significantly associated with the presence and duration of systemic inflammatory response syndrome and the severity of multiple, respiratory, central nervous, and cardiovascular organ failures. The median duration of mechanical ventilation was significantly longer in patients with CIPM than in those without (16 vs 3 days, p<0.001). Independent predictors of CIPM obtainable within the 1(st) week of critical illness were the admission sequential organ failure assessment score (odds ratio [OR], 1.15; 95% confidence interval [CI], 1.02-1.36), the 1(st) week total sequential organ failure assessment scores (OR, 1.14; 95 % CI, 1.06-1.46) and the 1(st) week duration of systemic inflammatory response syndrome (OR, 1.05; 95% CI, 1.01-1.15). They were able to correctly predict the development of CIPM at the end of the 1(st) week in about 80% of critically ill cases.In conclusion, the presence and duration of systemic inflammatory response syndrome and the severity of multiple and several organ failures are associated with increased risk of the development of CIPM.

TNF and TNFR polymorphisms in severe sepsis and septic shock: a prospective multicentre study

Tumour necrosis factor (TNF) is an important pro-inflammatory cytokine produced in sepsis. Studies examining the association of individual TNF single nucleotide polymorphisms with sepsis have produced conflicting results. This study investigated whether common polymorphisms of the TNF locus and the two receptor genes, TNFRSF1A and TNFRSF1B, influence circulating levels of encoded proteins, and whether individual polymorphisms or extended haplotypes of these genes are associated with susceptibility, severity of illness or outcome in adult patients with severe sepsis or septic shock. A total of 213 Caucasian patients were recruited from eight intensive care units (ICU) in the UK and Australia. Plasma levels of TNF (P = 0.02), sTNFRSF1A (P = 0.005) and sTNFRSF1B (P = 0.01) were significantly higher in those who died on ICU compared to those who survived. There was a positive correlation between increasing soluble receptor levels and organ dysfunction (increasing SOFA score) (sTNFRSF1A R = 0.51, P < 0.001; sTNFRSF1B R = 0.53, P < 0.001), and in particular with the degree of renal dysfunction. In this study, there were no significant associations between the selected candidate TNF or TNF receptor polymorphisms, or their haplotypes, and susceptibility to sepsis, illness severity or outcome. The influence of polymorphisms of the TNF locus on susceptibility to, and outcome from sepsis remains uncertain.

Modulation of asymmetric dimethylarginine in critically ill patients receiving intensive insulin treatment: A possible explanation of reduced morbidity and mortality?*

OBJECTIVE

Asymmetric dimethylarginine, which inhibits production of nitric oxide, has been shown to be a strong and independent predictor of mortality in critically ill patients with clinical evidence of organ dysfunction. Interestingly, intensive insulin therapy in critically ill patients improved morbidity and mortality, but the exact mechanisms by which these beneficial effects are brought about remain unknown. Therefore, we aimed to investigate whether modulation of asymmetric dimethylarginine concentrations by intensive insulin therapy is involved in these effects.

DESIGN

A prospective, randomized, controlled trial.

SETTING

A 56-bed predominantly surgical intensive care unit in a tertiary teaching hospital.

PATIENTS

From a study of 1,548 critically ill patients who were randomized to receive either conventional or intensive insulin therapy, we included 79 patients who were admitted to the intensive care unit after complicated pulmonary and esophageal surgery and required prolonged (>/=7 days) intensive care.

INTERVENTIONS

Determination of asymmetric dimethylarginine concentrations.

MEASUREMENTS AND MAIN RESULTS

Asymmetric dimethylarginine concentrations were determined with high-performance liquid chromatography on the day of admission, on day 2, on day 7, and on the last day at the intensive care unit. Although the asymmetric dimethylarginine levels did not change between day 0 and day 2 in patients receiving intensive insulin treatment, there was a significant increase during this period in the conventionally treated patients (p = .043). Interestingly, the mean daily insulin dose was inversely associated with the asymmetric dimethylarginine concentration on the last day (r = -.23, p = .042), and the asymmetric dimethylarginine concentration on the last day at the intensive care unit was significantly lower in the intensive insulin treatment group (p = .048). Furthermore, asymmetric dimethylarginine was positively associated with duration of intensive care unit stay, duration of ventilatory support, duration of inotropic and vasopressor treatment, number of red cell transfusions, duration of antibiotic treatment, presence of critical illness polyneuropathy, mean Acute Physiology and Chronic Health Evaluation II score, and cumulative Therapeutic Intervention Scoring System-28 score. In addition, asymmetric dimethylarginine levels in patients who died were significantly higher compared with survivors, and changes in the course of asymmetric dimethylarginine plasma concentrations were predictive for adverse intensive care unit outcome.

CONCLUSIONS

Modulation of asymmetric dimethylarginine concentration by insulin at least partly explains the beneficial effects found in critically ill patients receiving intensive insulin therapy.

Neuroanesthesia and Intensive Care Limited ability of SOFA and MOD scores to discriminate outcome: a prospective evaluation in 1,436 patients

PURPOSE

The multiple organ dysfunction (MOD) score and sequential organ failure assessment (SOFA) score are measures of organ dysfunction and have been validated based on the association of these scores with mortality. We sought to compare the performance of the SOFA and MOD scores in a large cohort of consecutive multisystem intensive care unit (ICU) patients.

METHODS

Prospective automated daily measurements of MOD and SOFA scores were performed in 1,436 patients admitted to a multisystem ICU in the Calgary Health Region over a one-year period. Logistic regression modeling techniques were used to describe the association of SOFA and MODS with mortality. Receiver operator characteristic (ROC) curves were used to assess the model's discriminatory ability.

RESULTS

For ICU and hospital mortality, there was very little practical difference between the SOFA and MOD scores in their ability to discriminate outcome as determined by the area under the ROC. However, compared to previous literature, the discriminatory ability of both scores in this population was weak. As well, the calibration of the models was poor for both scores. The SOFA cardiovascular component score performed better than the MOD cardiovascular component score in the discrimination of both ICU and hospital mortality.

CONCLUSIONS

SOFA and MOD scores had only a modest ability to discriminate between survivors and non-survivors. These results question the appropriateness of using organ dysfunction scores as a 'surrogate' for mortality in clinical trials and suggest further work is necessary to better understand the temporal relationship and course of organ failure with mortality.

Use of the Sequential Organ Failure Assessment score as a severity score

OBJECTIVE

To evaluate whether the SOFA score can be used to develop a model to predict intensive care unit (ICU) mortality in different countries.

DESIGN AND SETTING

Analysis of a prospectively collected database. Patients with ICU stay longer than 2 days were studied to develop a mortality prediction model based on measurements of organ dysfunction.

PATIENTS

748 patients from six countries.

MEASUREMENTS AND RESULTS

Two logistic regression models were constructed, one based on the SOFA maximum (SOFA Max model) and the other on variables identified by multivariate regression (SOFA Max-infection model). The H and C statistics had a p value above 0.05 for both models, but the D statistics showed a poor performance on the SOFA Max model when stratified for the presence of infection. Subsequent analysis was performed with SOFA Max-infection model. The area under the curve was 0.853. There were no statistically significant differences in observed and predicted mortalities except for one country which had a higher than predicted ICU mortality both in the overall population (28.3 vs. 19.1%) and in the noninfected patients (21.4 vs. 12.6%).

CONCLUSIONS

The SOFA Max adjusted for age and the presence of infection can predict mortality in this population, but in one country the ICU mortality was higher than expected. Our data do not allow us to determine the reasons behind these differences, and further studies to detect differences in mortality between countries and to elucidate the basis for these differences should be encouraged.

Prospective validation of the International Society of Thrombosis and Haemostasis scoring system for disseminated intravascular coagulation*

OBJECTIVES

A diagnosis of disseminated intravascular coagulation (DIC) is hampered by the lack of an accurate diagnostic test. Based on the retrospective analysis of studies in patients with DIC, a scoring system (0-8 points) using simple and readily available routine laboratory tests has been proposed. The aim of this study was to prospectively validate this scoring system and assess its feasibility, sensitivity, and specificity in a consecutive series of intensive care patients.

DESIGN

Prospective cohort of intensive care patients.

SETTING

Adult intensive care unit in a tertiary academic center.

PATIENTS

Consecutive patients with a clinical suspicion of disseminated intravascular coagulation.

INTERVENTIONS

Patients were followed during their admission to the intensive care unit, and the DIC score was calculated every 48 hrs and compared with a "gold standard" based on expert opinion. In addition, an activated partial thromboplastin time (aPTT) waveform analysis, which has been reported to be a good predictor for the absence or presence of DIC, was performed.

MEASUREMENTS AND MAIN RESULTS

We analyzed 660 samples from 217 consecutive patients. The prevalence of DIC was 34%. There was a strong correlation between an increasing DIC score and 28-day mortality (for each 1-point increment in the DIC score, the odds ratio for mortality was 1.25). The sensitivity of the DIC score was 91% and the specificity 97%. An abnormal aPTT waveform was seen in 32% of patients and correlated well with the presence of DIC (sensitivity 88%, specificity 97%). In 19% of patients, the aPTT waveform-based diagnosis of DIC preceded the diagnosis based on the scoring system.

CONCLUSIONS

A diagnosis of DIC based on a simple scoring system, using widely available routine coagulation tests, is sufficiently accurate to make or reject a diagnosis of DIC in intensive care patients with a clinical suspicion of this condition. An aPTT waveform analysis is an interesting and promising tool to assist in the diagnostic management of DIC.

Outcome of patients with end-stage renal disease admitted to the intensive care unit

OBJECTIVES

To describe the clinical course of patients with end-stage renal disease (ESRD) admitted to the intensive care unit (ICU) and to compare the performance of Acute Physiology and Chronic Health Evaluation (APACHE) III and Sequential Organ Failure Assessment (SOFA) in predicting their outcome.

PATIENTS AND METHODS

This retrospective cohort study consisted of patients with ESRD admitted to 3 ICUs between January 1, 1997, and November 30, 2002. Data on demographics, APACHE III score, SOFA score, development of sepsis and organ failure, use of mechanical ventilation, and mortality were collected.

RESULTS

Of the 476 patients with ESRD who underwent dialysis during the study period, 93 (20%) required admission to the ICU. The most common ICU admission diagnosis was gastrointestinal bleeding. The first day median (Interquartile range) APACHE III score, SOFA score, and APACHE III predicted hospital mortality rate were 64 (47-79), 6 (5-8), and 12.9% (4.2%-30.8%), respectively. The observed ICU, hospital, and 30-day mortality rates were 9%, 16%, and 22%, respectively. Nonrenal organ failure developed in 48 patients (52%) and sepsis in 15 patients (16%). Mechanical ventilation was required In 26 patients (28%). The area under the receiver operating characteristic curve for the first-day APACHE III probability of hospital death in predicting 30-day mortality was 0.78 (95% confidence interval, 0.68-0.86) compared with 0.66 (95% confidence interval, 0.55-0.76) for the SOFA score (P = .16).

CONCLUSIONS

The observed hospital mortality of patients with ESRD admitted to the ICU is relatively low. There is no statistically significant difference in the performance of APACHE III and SOFA prognostic models in discriminating between 30-day survivors and nonsurvivors.

Dynamic microsimulation to model multiple outcomes in cohorts of critically ill patients

BACKGROUND

Existing intensive care unit (ICU) prediction tools forecast single outcomes, (e.g., risk of death) and do not provide information on timing.

OBJECTIVE

To build a model that predicts the temporal patterns of multiple outcomes, such as survival, organ dysfunction, and ICU length of stay, from the profile of organ dysfunction observed on admission.

DESIGN

Dynamic microsimulation of a cohort of ICU patients.

SETTING

49Forty-nine ICUs in 11 countries.

PATIENTS

One thousand four hundred and forty-nine patients admitted to the ICU in May 1995.

INTERVENTIONS

None. MODEL CONSTRUCTION: We developed the model on all patients (n=989) from 37 randomly-selected ICUs using daily Sequential Organ Function Assessment (SOFA) scores. We validated the model on all patients (n=460) from the remaining 12 ICUs, comparing predicted-to-actual ICU mortality, SOFA scores, and ICU length of stay (LOS).

MAIN RESULTS

In the validation cohort, the predicted and actual mortality were 20.1% (95%CI: 16.2%-24.0%) and 19.9% at 30 days. The predicted and actual mean ICU LOS were 7.7 (7.0-8.3) and 8.1 (7.4-8.8) days, leading to a 5.5% underestimation of total ICU bed-days. The predicted and actual cumulative SOFA scores per patient were 45.2 (39.8-50.6) and 48.2 (41.6-54.8). Predicted and actual mean daily SOFA scores were close (5.1 vs 5.5, P=0.32). Several organ-organ interactions were significant. Cardiovascular dysfunction was most, and neurological dysfunction was least, linked to scores in other organ systems.

CONCLUSIONS

Dynamic microsimulation can predict the time course of multiple short-term outcomes in cohorts of critical illness from the profile of organ dysfunction observed on admission. Such a technique may prove practical as a prediction tool that evaluates ICU performance on additional dimensions besides the risk of death.

Finding optimal decision scores by evolutionary strategies

OBJECTIVE

Severeness of illness is often rated by physicians at admission time. For this purpose, medical scores have been developed as 'objective' rating methods. When considering their classification performance, it is not assumed that such an expert-driven score is an optimal one. Our aim is to design an optimized data-driven score. In particular, we compare classical scores with a new data-driven score for abdominal septic shock patients.

METHODS AND MATERIAL

Medical scores are used as ratings for different aspects of a patient's health status. The medical score indicates either a more critical or a healthier condition. For example, physicians rate organ conditions for different organs. We consider four different scores, SOFA, APACHE II, SAPS II, and MODS. Beyond the use of such classical scores, we propose an evolutionary strategy, that is suitable for score design, to find optimized data-driven scores. A database of 282 patients is used to optimize a new score for abdominal septic shock patients. Classification performance is compared by a ROC analysis.

RESULTS

We give a general instruction for building optimized scores, i.e. we define individuals and operators for the evolutionary score design task. We apply this instruction to abdominal septic shock patient data. When compared to the SOFA score, it has similar classification performance, but it is more performant than APACHE II, SAPS II, and MODS. It can be used as a daily bedside score.

CONCLUSIONS

We argue that evolutionary strategies should be used for optimizing purposes in the medical score design process. Using abdominal septic shock patient data, we show that evolutionary score design is a feasible and performant method that can complement or replace expert knowledge, provided that qualitative data is available.

Procalcitonin and C-reactive protein during systemic inflammatory response syndrome, sepsis and organ dysfunction

Introduction

Both C-reactive protein (CRP) and procalcitonin (PCT) are accepted sepsis markers. However, there is still some debate concerning the correlation between their serum concentrations and sepsis severity. We hypothesised that PCT and CRP concentrations are different in patients with infection or with no infection at a similar severity of organ dysfunction or of systemic inflammatory response.

Patients and methods

One hundred and fifty adult intensive care unit patients were observed consecutively over a period of 10 days. PCT, CRP and infection parameters were compared among the following groups: no systemic inflammatory response syndrome (SIRS) (n = 15), SIRS (n = 15), sepsis/SS (n = 71) (including sepsis, severe sepsis and septic shock [n = 34, n = 22 and n = 15]), and trauma patients (n = 49, no infection).

Results

PCT and CRP concentrations were higher in patients in whom infection was diagnosed at comparable levels of organ dysfunction (infected patients, regression of median [ng/ml] PCT = -0.848 + 1.526 sequential organ failure assessment [SOFA] score, median [mg/l] CRP = 105.58 + 0.72 SOFA score; non-infected patients, PCT = 0.27 + 0.02 SOFA score, P < 0.0001; CRP = 84.53 - 0.19 SOFA score, P < 0.005), although correlation with the SOFA score was weak (R = 0.254, P < 0.001 for PCT, and R = 0.292, P < 0.001 for CRP). CRP levels were near their maximum already during lower SOFA scores, whereas maximum PCT concentrations were found at higher score levels (SOFA score > 12).

PCT and CRP concentrations were 1.58 ng/ml and 150 mg/l in patients with sepsis, 0.38 ng/ml and 51 mg/l in the SIRS patients (P < 0.05, Mann–Whitney U-test), and 0.14 ng/ml and 72 mg/l in the patients with no SIRS (P < 0.05). The kinetics of both parameters were also different, and PCT concentrations reacted more quickly than CRP.

Conclusions

PCT and CRP levels are related to the severity of organ dysfunction, but concentrations are still higher during infection. Different sensitivities and kinetics indicate a different clinical use for both parameters.

Hyperglycaemia and mortality in critically ill patients. A prospective study

OBJECTIVE

To describe hyperglycaemia as a possible marker of morbidity and mortality in critically ill medical and surgical patients admitted to a multidisciplinary ICU.

DESIGN

Prospective cohort study.

SETTING

A 13-bed non-cardiac multidisciplinary ICU in a university hospital.

PATIENTS AND PARTICIPANTS

Adult patients consecutively admitted to the ICU in a 6-month period. Patients with fewer than 2 days' stay in the ICU and patients with known diabetes were excluded.

MEASUREMENTS AND RESULTS

At admission a registration form was filled in including demographic data, first and second day APACHE II scores, infections and daily maximum blood glucose level. In surgical patients, high maximum blood glucose level during the stay in ICU was correlated with increased mortality, morbidity and frequency of infection. In medical patients, we found a non-significant trend towards a correlation between hyperglycaemia and morbidity and mortality, respectively.

CONCLUSIONS

High blood glucose level during the stay in ICU was a marker of increased morbidity and mortality in critically ill surgical patients. In medical patients the same trend was found, but non-significant. The population of patients in the present study are heterogeneous and the results from surgical critically ill patients should not be generalised to medical patients.

Utility of activated partial thromboplastin time waveform analysis for identification of sepsis and overt disseminated intravascular coagulation in patients admitted to a surgical intensive care unit

OBJECTIVE

An abnormality of the optical transmission waveform obtained during measurement of the activated partial thromboplastin time (aPTT) has been described in association with overt disseminated intravascular coagulation. This abnormality, a biphasic waveform, is caused by the in vitro formation of Ca2+-induced complexes between very low density lipoprotein and C-reactive protein. We have evaluated the diagnostic utility of aPTT waveform analysis for identifying patients with overt disseminated intravascular coagulation and sepsis.

DESIGN

Observational study investigating the predictive value of biphasic waveform for the diagnosis of sepsis and overt disseminated intravascular coagulation.

SETTING

Surgical intensive care unit of a university hospital.

SUBJECTS

We studied 331 consecutive patients admitted to the intensive care unit during a period of 6 months.

INTERVENTIONS

Laboratory analyses, including prothrombin time, aPTT, aPTT waveform analysis, fibrinogen, D-dimer antigen, and platelet count.

MEASUREMENTS AND MAIN RESULTS

At the most sensitive threshold value of the waveform variable for detection of the biphasic waveform (slope_1 = -0.05 %T/sec), this abnormality was detected in 54 of 331 patients (16.3%) at admission and 95 of 331 patients (28.7%) during the entire course of intensive care unit treatment. At this threshold, 59.3% of patients with a biphasic waveform on admission and 45.3% with a biphasic waveform during the total intensive care unit course were diagnosed with sepsis. Depending on the threshold value of slope_1, the sensitivity of aPTT waveform analysis for detection of sepsis varied between 22% and 55% at admission and between 48% and 74% during the entire intensive care unit stay. The specificity for sepsis varied between 92% and 98% and between 81% and 94%, for admission and total intensive care unit course, respectively. Biphasic waveform showed a comparable specificity for the diagnosis of overt disseminated intravascular coagulation, albeit at a lower sensitivity.

CONCLUSIONS

As an adjunct to routine coagulation testing in intensive care unit patients, aPTT waveform analysis is an elegant means for the rapid and highly specific identification of patients with sepsis.

Administration of the nitric oxide synthase inhibitor NG-methyl-L-arginine hydrochloride (546C88) by intravenous infusion for up to 72 hours can promote the resolution of shock in patients with severe sepsis: results of a randomized, double-blind, placebo-controlled multicenter study (study no. 144-002)

OBJECTIVE

To assess the safety and efficacy of the nitric oxide synthase inhibitor 546C88 in patients with septic shock. The predefined primary efficacy objective was resolution of shock, defined as a mean arterial pressure > or =70 mm Hg in the absence of both conventional vasopressors and study drug, determined at the end of the 72-hr treatment period.

DESIGN

Multicentered, randomized, placebo-controlled, safety and efficacy study.

SETTING

Forty-eight intensive care units in Europe, North America, and Australia.

PATIENTS

A total of 312 patients with septic shock diagnosed within 24 hr before randomization.

INTERVENTIONS

Patients were randomly allocated to receive either 546C88 or placebo (5% dextrose) by intravenous infusion for up to 72 hrs. Conventional vasoactive therapy was restricted to norepinephrine, dopamine, and dobutamine. Study drug was initiated at 0.1 mL/kg/hr (5 mg/kg/hr 546C88) and titrated according to response up to a maximum rate of 0.4 mL/kg/hr with the objective to maintain mean arterial pressure at 70 mm Hg while attempting to withdraw any concurrent vasopressor(s).

MEASUREMENTS AND MAIN RESULTS

Requirement for vasopressors, systemic hemodynamics, indices of organ function and safety (including survival up to day 28) were assessed. The median mean arterial pressure for both groups was maintained >70 mm Hg. Administration of 546C88 was associated with a decrease in cardiac index while stroke index was maintained. Resolution of shock at 72 hr was achieved by 40% and 24% of the patients in the 546C88 and placebo cohorts, respectively (p =.004). There was no evidence that treatment with 546C88 had any major adverse effect on pulmonary, hepatic, or renal function. Day 28 survival was similar for both groups.

CONCLUSIONS

In this study, treatment with the nitric oxide synthase inhibitor 546C88 promoted the resolution of shock in patients with severe sepsis. This was associated with an acceptable overall safety profile.

Prognostication and intensive care unit outcome: the evolving role of scoring systems

Prognostic scoring systems remain important in clinical practice. They enable us to characterize our patient populations with robust measures for predicted mortality. This allows us to audit our own experience in the context of institutional quality control measures and facilitates, albeit imperfectly, comparisons across units and patient populations. Practically, they provide an objective means to characterize case-mix and this helps to quantify resource needs when negotiating with hospital administrators for funding. Prognostic scores also help to stratify patient populations for research purposes. To be used accurately and effectively, one must have a good understanding of the limitations that are intrinsic to these prognostic systems. It is important to understand the details of their derivation and validation. The population of patients that is used to develop the models may not be relevant to your patient population. The model may have been derived several years before and may no longer reflect current practice patterns and treatment. These models may become obsolete over time. As with all scoring systems, there are potential problems with misclassification and more serious, systematic error, in data collection. One needs to rigorously adhere to guidelines about how these data are to be collected and processed; the persons who collect the data require regular updates and ongoing training. In their current form, the systems should not be used to prognosticate in individual patients, nor should they be used to define medical futility. The prognostic models should be viewed as being in evolution. Many patient and ICU characteristics that seem to have an important impact on mortality have yet to be incorporated into any of the current models. As an example, these may include the genetic characteristics of the patients and the ICU's organizational structure and process of care [51, 52]. Because the organ dysfunction measures are able to be obtained daily they give a much more complete understanding of the patient's entire ICU course as opposed to the initial 24-hour period. Daily scores also help to capture the intensity of resource use and may help us gain a better understanding of what is truly ICU-acquired organ dysfunction. These measures may also be used for research to better characterize the natural history and course of a certain disease group or population. Also, they may be used in innovative ways to predict ICU mortality and post-ICU long-term morbidity. These current and developing applications will help us to further understand the link between ICU severity of illness and long-term morbidity as we move beyond survival as the sole measure of ICU outcome.

Intermittent high permeability hemofiltration in septic patients with acute renal failure

OBJECTIVE

High permeability hemofiltration (HP-HF) is a new renal replacement modality designed to facilitate the elimination of cytokines in sepsis. Clinical safety data on this new procedure is still lacking. This study investigates the effects of HP-HF on the protein and coagulation status as well as on cardiovascular hemodynamics in patients with septic shock. In addition, the clearance capacity for interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha) is analyzed.

DESIGN

Prospective, single-center pilot trial.

SETTING

University hospital.

PATIENTS

Sixteen patients with multiple organ failure (MOF) induced by septic shock were studied.

INTERVENTION

Patients were treated by intermittent high permeability hemofiltration (iHP-HF; nominal cut-off point: 60 kilodaltons). Intermittent HP-HF was performed over 5 days for 12 h per day and alternated with conventional hemofiltration.

MEASUREMENTS AND RESULTS

Intermittent HP-HF proved to be a safe hemofiltration modality in regard to cardiovascular hemodynamics and its impact on the coagulation status. However, transmembrane protein loss occurred and cumulative 12-h protein loss was 7.60 g (IQR: 6.2-12.0). The filtration capacity for IL-6 was exceptionally high. The IL-6 sieving coefficient approximated 1 throughout the study period. The total plasma IL-6 burden, estimated by area under curve analysis, declined over time ( p<0.001 vs baseline). The TNF-alpha elimination capacity was poor.

CONCLUSIONS

High permeability hemofiltration is a new approach in the adjuvant therapy of sepsis that facilitates the elimination of cytokines. HP-HF alternating with conventional hemofiltration is well tolerated. Further studies are needed to analyze whether HP-HF is able to mitigate the course of sepsis.

Validation of the multiple organ dysfunction (MOD) score in critically ill medical and surgical patients

OBJECTIVE

To validate the Multiple Organ Dysfunction (MOD) score externally.

DESIGN

Prospective observational cohort study.

SETTING

Mixed medical/surgical ICU in a tertiary referral university hospital.

PATIENTS AND PARTICIPANTS

Thousand eight hundred and nine patients admitted to ICU for more than 24 h over a 3-year period.

INTERVENTIONS

None.

MEASUREMENTS AND RESULTS

The MOD score was calculated daily for all patients. The criterion validity of the individual organ scores, the maximal MOD score and the change in MOD score were assessed by examining the relationship between increasing scores and ICU mortality. Increased maximal MOD scores and each of the six individual organ scores, and change in MOD scores were associated with increased mortality.

CONCLUSIONS

Maximal and individual organ scores have criterion validity when tested in a different ICU from that in which the scores were derived, indicating that the scoring systems are reproducible. The association of change in MOD score with mortality indicates that the score is responsive. These data, combined with previous data establishing concept and content validity, indicate that the MOD score is a valid measure of multi-organ dysfunction.

Critical illness polyneuromyopathy: the electrophysiological components of a complex entity

OBJECTIVE

To evaluate the spectrum and time profile of electrophysiological parameters in the detection of neuromuscular involvement in critically ill patients and establish their correlation with biopsy findings.

DESIGN

Prospective clinical and neurophysiological study.

SETTING

One general and one neurological intensive care unit in a university hospital.

PATIENTS

Forty-six critically ill patients with failure of at least two organ systems were enrolled and completed the 1-month follow up.

INTERVENTIONS

Detailed clinical and electrophysiological evaluation including direct muscle stimulation was performed in all cases on entry and at the end of the follow-up. Muscle biopsy was performed in 11, and sural nerve biopsy in 5, cases.

MEASUREMENTS AND RESULTS

Electrophysiological signs of new or progressing neuromuscular involvement at the end of the first month were detected in 26 patients (56%) and could be classified into three groups: "pure motor syndrome" (12 cases), combined motor syndrome and sensory polyneuropathy (13 cases) and isolated sensory polyneuropathy (1 case). Direct muscle stimulation showed decreased muscle membrane excitability in 11 of these abnormal cases. Muscle biopsy disclosed various myopathic abnormalities in all 11 cases examined with motor syndrome, in 7 of them in association with denervation/re-innervation changes.

CONCLUSIONS

Electrophysiological and histological examinations showed significant overlapping of several pathogenic components of neuromuscular involvement in critically ill patients, namely decreased muscle excitability, myopathy, axonal motor neuropathy and sensory neuropathy. The characterisation of the electrophysiological components of a complex polyneuromyopathy is preferred to the strict categorisation of abnormalities into critical illness myopathy and polyneuropathy.

The sequential organ failure assessment score as a useful predictor for estimating the prognosis of systemic inflammatory response syndrome patients being treated with extracorporeal blood purification

Systemic inflammatory response syndrome (SIRS) is a major cause of morbidity and mortality in critically ill patients. Extracorporeal blood purification procedures are becoming important for treating these patients. However, the cost of these procedures is high. Therefore, a prognostic marker would be helpful. To establish the reliability of the Sequential Organ Failure Assessment (SOFA) score as a prognostic indicator, we evaluated daily changes in the SOFA score of 40 SIRS patients who needed blood purification procedures such as continuous renal replacement therapy (CRRT), endotoxin adsorption, bilirubin adsorption, and/or plasma exchange. Twenty patients survived and 20 died. Although the baseline scores of the two groups (survivors and non-survivors) did not differ, both the maximum value of the SOFA score and the DeltaSOFA score (the difference between the maximum SOFA and baseline SOFA scores) were significantly higher in the non-survivor group. The mortality rate among patients with a maximum SOFA score greater than or equal to 18 or a DeltaSOFA score greater than or equal to 3 was higher than for the rest of the patients. The changes in the SOFA score correlated well with the outcomes of the SIRS patients. The maximum SOFA score and the DeltaSOFA score are therefore likely to be useful prognostic markers.

Resolution and outcome of acute circulatory failure does not correlate with hemodynamics

INTRODUCTION

Hemodynamic goals in the treatment of acute circulatory failure (ACF) are controversial. In critical care, organ failures can be assessed using Sequential Organ Failure Assessment and its refinement, total maximal Sequential Organ Failure Assessment (TMS). We studied the associations between resolution of ACF and hemodynamics in the early (< 24 hours) phase of intensive care unit care and their relation to TMS and mortality.

PATIENTS AND METHODS

Eighty-three patients with ACF (defined as arterial lactate > 2 mmol/l and/or base deficit > 4) who had pulmonary artery catheters and stayed for longer than 24 hours in the intensive care unit were included. Hemodynamics, oxygen transport, vasoactive drugs and TMS scores were recorded. Normalisation of hyperlactatemia and metabolic acidosis in less than 24 hours after admission was defined as a positive response to hemodynamic resuscitation.

RESULTS

Fifty-two patients responded to resuscitation. Nonresponders had higher mortality than responders (52% versus 33%, P = 0.044). Hospital mortality was highest (63%) among nonresponders who received vasoactive drugs. The TMS scores of nonresponders (median [interquartile range], 12 9-16) were higher than the scores of responders (10 7-12, P = 0.019). Late accumulation of TMS scores was associated with increasing mortality, and if the TMS score increase occurred > 5 days after admission then the mortality was 77%. Responders had higher mean arterial pressure at 24 hours, but it was no different between survivors and nonsurvivors. No other hemodynamic and oxygen transport variables were associated with the success of resuscitation or with mortality.

CONCLUSIONS

Except for the mean arterial pressure at 24 hours, invasively derived hemodynamic and oxygen transport variables are not associated with the response to resuscitation or with mortality. Positive response to resuscitation in ACF is associated with less severe organ failures as judged by TMS scores. Late accumulation of the TMS score predicts poor outcome.

Validation of the paediatric logistic organ dysfunction (PELOD) score: prospective, observational, multicentre study

BACKGROUND

Multiple organ dysfunction syndrome is more frequent than death in paediatric intensive care units. Estimation of the severity of this syndrome could be a useful additional outcome measure in clinical trials in such units. We aimed to validate the paediatric logistic organ dysfunction (PELOD) score and estimate its validity when recorded daily (dPELOD).

METHODS

We did a prospective, observational, multicentre cohort study in seven multidisciplinary, tertiary-care paediatric intensive care units of university-affiliated hospitals (two French, three Canadian, and two Swiss). We included 1806 consecutive patients (median age 24 months; IQR 5-90). PELOD score includes six organ dysfunctions and 12 variables and was recorded daily. For each variable, the most abnormal value each day and during the whole stay were used in calculating the dPELOD and PELOD scores, respectively. Outcome was vital status at discharge. We used Hosmer-Lemeshow goodness-of-fit tests to evaluate calibration and areas under receiver operating characteristic curve (AUC) to estimate discrimination.

FINDINGS

370 (21%) patients had no organ dysfunction, 471 (26%) had one, 457 (25%) had two, and 508 (28%) had three or more. Case fatality rate was 6.4% (115 deaths). PELOD score was significantly higher in non-survivors (mean 31.0 [SE 1.2]) than survivors (9.4 [0.2]; p<0.0001). Calibration (p=0.54) and discrimination (AUC=0.91, SE=0.01) of PELOD and dPELOD (p> or =0.39; AUC> or =0.79) scores were good.

INTERPRETATION

PELOD and dPELOD scores are valid outcome measures of the severity of multiple organ dysfunction syndrome in paediatric intensive care units; their use should significantly reduce the sample size required to complete clinical trials in critically ill children.

Compartmentalization of the inflammatory response during acute pancreatitis: correlation with local and systemic complications

Local and systemic inflammation has been implicated in the pathogenesis of acute pancreatitis and secondary multisystem organ failure. To assess the pro- and antiinflammatory response, the site of mediator production, and their route of diffusion, we sampled simultaneously ascites, thoracic lymph, and blood at the onset of end-organ dysfunction and for the following 6 days in 60 patients with acute pancreatitis. We used immunoassays to measure pro- and antiinflammatory cytokines and cell-based bioassays to assess the net pro- and antiinflammatory activity elicited by the biological fluids. Tumor necrosis factor-alpha and interleukin-1beta were detected in less than 15% of blood and lymph samples. Secondary pro- and antiinflammatory cytokines were found to be elevated early and throughout the sampling period in all compartments. Cytokine levels decreased from ascites to lymph to blood, suggesting a splanchnic origin. Prolonged diversion of ascites and lymph did not alter cytokine gradients, suggesting mediator transfer via the splanchnic blood circulation. Although a net proinflammatory activity ascribed to interleukin-1beta was detected in ascites, a net antiinflammatory activity was measured in virtually all lymph and blood samples, suggesting that the pancreas and the splanchnic area are sites of a proinflammatory response and that an early, dominant, and sustained antiinflammatory activity takes place in circulating compartments.

Effects of dopamine, norepinephrine, and epinephrine on the splanchnic circulation in septic shock: which is best?

OBJECTIVE

To assess the effects of different doses of dopamine, norepinephrine, and epinephrine on the splanchnic circulation in patients with septic shock.

DESIGN

Prospective, randomized, open-label study.

SETTING

A 31-bed, medicosurgical intensive care unit of a university hospital.

PATIENTS

Convenience sample of 20 patients with septic shock, separated into two groups according to whether (moderate shock group, n = 10) or not (severe shock, n = 10) dopamine alone was able maintain mean arterial pressure >65 mm Hg.

INTERVENTIONS

Dopamine was progressively withdrawn and replaced successively by norepinephrine and then epinephrine (the order of the two agents was randomly determined) to maintain mean arterial pressure constant (moderate shock) or to increase mean arterial pressure above 65 mm Hg (severe shock).

MEASUREMENTS AND MAIN RESULTS

Systemic circulation (pulmonary artery catheter) and splanchnic circulation (indocyanine green dilution and hepatic vein catheter) and gastric mucosal Pco(2) (gas tonometry) were measured during dopamine (moderate shock only), norepinephrine, and epinephrine administration (both groups). Data were analyzed with nonparametric tests and are presented as median [percentiles 25-75]. In moderate shock, cardiac index was similar to dopamine and norepinephrine (3.1 [2.7-3.8] vs. 2.9 [2.7-4.1] L/min.m2, p = nonsignificant) but greater with epinephrine (4.1 [3.5-4.4] p <.01 vs. dopamine and norepinephrine). Splanchnic blood flow was similar with the three agents (732 [413-1483] vs. 746 [470-1401] vs. 653 [476-1832] mL/min.m, p = nonsignificant). The gradient between mixed-venous and hepatic venous oxygen saturations was lower with dopamine than with norepinephrine and epinephrine, but the Pco(2) gap was similar with the three agents. In severe shock, cardiac index was higher, but splanchnic blood flow was lower, with epinephrine than with norepinephrine (4.6 [3.7-5.3] vs. 3.4 [3.0-4.1] L/min.m2, p <.01 and 860 [684-1334] vs. 977 [806-1802] mL/min.m2, p <.05, respectively). Epinephrine increased the mixed-venous and hepatic venous oxygen saturation gradient but did not alter Pco(2) gap.

CONCLUSIONS

Dopamine and norepinephrine have similar hemodynamic effects, but epinephrine can impair splanchnic circulation in severe septic shock.

Outcome analysis of 189 consecutive cancer patients referred to the intensive care unit as emergencies during a 2-year period

The referral of critically ill cancer patients to an intensive care unit (ICU) is a matter of controversial debate. This study was conducted by an interdisciplinary clinical group to evaluate the outcome of ICU treatment in cancer patients according to their characteristics at the time of referral. A retrospective analysis was used to identify relevant subgroups among 189 consecutive cancer patients referred as emergencies to one of four ICUs during a 2-year period. Reasons for ICU referral were pneumonia (29.6%), sepsis (27.0%), fungal infection (11.1%), another infection (9.5%), gastrointestinal emergency (16.9%), treatment-related organ toxicity (6.9%), or other, non-infectious complications (43.9%). Vasopressor support was required in 50.3%, mechanical ventilation in 49.7%, and haemodialysis/-filtration in 26.5% of the patients. Overall, 41.3% died during ICU treatment, 12.2% died after transfer from ICU to a non-ICU ward, and 35.4% were discharged alive. Sepsis, mechanical ventilation, vasopressor support, renal replacement therapy and neutropenia were independent risk factors for fatal outcome, but no single risk factor unequivocally predicted death. All patients with fungal infection who required vasopressor support and either had sepsis (n=13) or needed mechanical ventilation (n=14) died during ICU treatment, while all non-septic patients. who did not require mechanical ventilation, were younger than 74 years of age and had a non-infectious underlying complication (n=29), survived. This analysis may help to early identify relevant subgroups of cancer patients with different prognoses under ICU treatment. A prospective study to confirm the predictive usefulness of this approach is needed. Cancer patients should not be excluded from referral to the intensive care unit in an emergency solely due to their underlying malignant disease or a single unfavourable prognostic factor.

Application of the sequential organ failure assessment score to cardiac surgical patients

OBJECTIVE

To assess the applicability of the sequential organ failure assessment (SOFA) score to cardiac surgical patients.

DESIGN

Observational cohort study.

SETTING

Adult cardiac surgical ICU.

PATIENTS

Two hundred eighteen patients requiring ICU stay > 96 h.

MEASUREMENTS AND RESULTS

The SOFA score was calculated daily until ICU discharge. Derived SOFA variables-total maximum SOFA (TMS), DeltaSOFA, maximum SOFA (maxSOFA), and DeltamaxSOFA-were considered. Length of ICU stay was 8.9 +/- 6.7 days (mean +/- SD). The mortality rate was 11.0% in the ICU and 15.6% in the hospital. Nonsurvivors had higher TMS, DeltaSOFA, single-organ system, and mean total scores on day 1 (9.8 +/- 2.5 vs 7.8 +/- 2.3, p < 0.05) and thereafter until day 10. The total SOFA score on the first 10 days of ICU stay, time, survival status, and their interaction were all significant (p < 0.001), with higher SOFA scores for nonsurvivors, and lower scores for survivors that decreased as the number of days from operation increased. Cardiovascular score on day 1 carried the highest relative risk of mortality among other systems (risk ratio [RR], 2.12; 95% confidence interval [CI], 1.31 to 3.45; p < 0.01), as did maximum cardiovascular score (RR, 2.81; 95% CI, 1.62 to 4.85; p < 0.001). A growing number of failing organs was associated with mortality, from the first to the sixth postoperative day (p < 0.05). Total score on day 1, TMS, DeltaSOFA, maxSOFA, and DeltamaxSOFA were reliable predictors of mortality with area under receiver operating characteristic curve of 0.71 (SE, 0.08), 0.89 (SE, 0.05), 0.86 (SE, 0.06), 0.88 (SE, 0.05), and 0.88 (SE, 0.06), respectively. Length of hospital stay was significantly associated (p = 0.05) to TMS and DeltaSOFA and not to other SOFA scores, age, or sex.

CONCLUSIONS

The SOFA score may be used to grade the severity of postoperative morbidity in cardiac surgical patients without specific adaptations. The model identifies patients at increased risk for postoperative mortality.

Microalbuminuria in critically ill medical patients: prevalence, predictors, and prognostic significance

OBJECTIVE

To ascertain the prevalence, predictors, and prognostic significance of microalbuminuria in critically ill patients.

DESIGN

Prospective cohort study.

SETTING

Medical intensive care unit of a community teaching hospital.

PATIENTS

Admitted critically ill patients.

MEASUREMENTS AND MAIN RESULTS

We measured serial spot urine albumin-creatinine ratios in 104 critically ill patients, with a median age of 64.5 yrs and median Acute Physiology and Chronic Health Evaluation (APACHE) II and Sequential Organ Failure Assessment (SOFA) scores of 20.5 and 5.0, respectively. Sixty-nine percent of the patients had microalbuminuria or clinical proteinuria and 43.3% had an albumin-creatinine ratio >/=100 mg/g at admission. The acuity of illness, being non-White, and having diabetes mellitus were independent predictors of albumin-creatinine ratio >/=100 mg/g. The overall mortality rate was 26.9% (28/104). Patients with an albumin-creatinine ratio >/=100 mg/g were 2.7 times as likely to die compared with those with an albumin-creatinine ratio <100 mg/g, even after simultaneous adjustments for age, and APACHE II and SOFA scores (odds ratio, 2.7; 95% confidence interval, 1.1-7.2, p =.04). The association of albumin-creatinine ratio >/=100 mg/g with death was consistent across age, ethnicity, renal function, acuity of illness, and comorbid conditions. Among survivors, patients with an albumin-creatinine ratio >/=100 mg/g stayed approximately 5 days longer in the hospital (p =.0007). Overall, the albumin-creatinine ratio shared similar predictive characteristics with APACHE II and SOFA scores.

CONCLUSIONS

This study confirms a high prevalence of microalbuminuria in critically ill patients and suggests that an albumin-creatinine ratio >/=100 mg/g is an independent predictor of mortality and hospital stay.

Lymphocyte subset numbers depend on the bacterial origin of sepsis

OBJECTIVE

To determine the quantitative variances in peripheral blood lymphocyte subsets during sepsis, and their clinical significance.

METHODS

Peripheral blood lymphocyte subsets were enumerated in 32 non-surgical septic patients during the first 14 days of hospitalization; results from septic patients were compared with those from 34 healthy controls. Influences of the severity and the bacterial etiology of sepsis on changes in lymphocyte subsets were also assessed.

RESULTS

Significant decreases (P < 0.05) from normal values of CD4+, CD8+ and total T-lymphocytes were observed in septic patients, but the decline persisted only for CD4+ T-lymphocytes and natural killer (NK) cells for 3 and 7 days, respectively. In addition, the numbers of CD3+/DR+ lymphocytes were significantly elevated on day 14. There were no correlations between these alterations and the severity of sepsis. Gram-positive sepsis (n = 10), which was mainly due to Streptococcus pneumoniae and Staphylococcus aureus, caused prolonged decreases in CD4+, CD8+ and total T-lymphocytes, and a reduction in NK cells, that lasted for >or=14 days. Conversely, patients with sepsis due to Gram-negative pathogens (Neisseria meningitidis, n = 8; enterobacteria, n = 2) achieved full recovery of the subsets within 3 days. Moreover, the patients with Gram-negative sepsis demonstrated a significant increase in B-lymphocytes, and a rise in the numbers of CD3+/DR+ and CD4+ T-lymphocytes, which were more rapid than in patients with Gram-positive sepsis.

CONCLUSION

Our results indicate that Gram-positive sepsis causes stronger suppression of peripheral blood lymphocyte subsets in comparison to sepsis due to Gram-negative pathogens.

Outcome after acute respiratory failure is more dependent on dysfunction in other vital organs than on the severity of the respiratory failure

INTRODUCTION

The incidence and outcome of acute respiratory failure (ARF) depend on dysfunction in other organs. As a result, reported mortality in patients with ARF is derived from a mixed group of patients with different degrees of multiorgan failure. The main goal of the present study was to investigate patient outcome in single organ ARF.

PATIENTS AND METHOD

From 1 January 2000 to 1 July 2002, all adult patients (>16 years) in the intensive care unit (ICU) at Haukeland University Hospital were scored daily using the Sequential Organ Failure Assessment (SOFA) score for organ failure. ARF was defined by the SOFA criteria: ratio of arterial oxygen tension to fractional inspired oxygen, with a value < 26.6 kPa (200 mmHg) in more than one recording during the ICU stay (SOFA score 3 or 4). Patients with ARF alone and in combination with other severe organ failure (SOFA score 3 or 4) were included. Survival was recorded on discharge from the ICU, at hospital discharge and at 90 days after ICU discharge.

RESULTS

During the period of study, 832 adult patients were treated and 529 (63.0%) had ARF. The ICU, hospital and 3-month mortality rates were lowest in single organ ARF (3.2, 14.7 and 21.8%, respectively), with increasing mortality with each additional organ failure. When ARF occurred with four or five additional organ failures, the 3-month mortality rate was 75%. No significant differences in mortality were found between early and late ARF.

CONCLUSION

The prognosis for ICU patients with single organ ARF is good, both in the short and long terms. The high overall mortality rate observed is caused by dysfunction in other organs.

Continuous venovenous hemofiltration: effects on monocyte and lymphocyte immunophenotype in critically ill patients

The aim of this study was to test the hypothesis that continuous venovenous hemofiltration (CVVH) increases HLA-DR expression on monocytes and T lymphocytes in critically ill patients. 24 septic (SP) and 10 non-septic (NSP) medical ICU patients with acute renal failure were studied prospectively. The ultrafiltration rate was 20-30 ml.kg(-1).h(-1). The total and differential white cell counts were measured and CD3+ lymphocyte count, HLA-DR expression on CD14+ monocytes and CD3+ lymphocytes were analysed by two-colour flow cytometry before, 4 and 24 h after CVVH initiation, respectively. CVVH did not influence leukocyte, granulocyte, total lymphocyte and CD3+ lymphocyte counts in both groups of patients. The percentage of HLA-DR+/CD14+ monocytes in SP revealed no changes, whereas it decreased after 4 h of CWH in NSP (p < 0.05). The percentage of HLA-DR+/CD3+ lymphocytes in SP decreased after 24 h (p < 0.05), whereas it remained unchanged in NSP. We conclude that CWH initiation is not associated with the increase of HLA-DR expression on CD14+ monocytes and T lymphocytes in critically ill patients with acute renal failure.

Prognosis of hematologic malignancies does not predict intensive care unit mortality

OBJECTIVE

To evaluate the correlation between specific prognosis of hematologic malignancies on the one hand and intensive care unit and hospital mortality in critically ill patients with hematologic malignancies on the other hand.

DESIGN

Observational study during a 10-yr period.

SETTING

A 22-bed medical-surgical intensive care unit.

PATIENTS

A total of 84 consecutive patients with nonterminal hematologic malignancies with medical complications requiring intensive care.

INTERVENTIONS

None.

MEASUREMENTS

Demographic factors, acute physiology and organ dysfunction scores, microbiology, therapeutic support, and hematologic factors data on admission and during the intensive care unit stay were collected, together with mortality follow-up. Based on specific-disease prognostic factors and related published survival curves, the prognosis of hematologic malignancies was assessed and defined as good, intermediate, or poor according to a 3-yr survival probability of >50%, 20-50%, or <20%, respectively.

MAIN RESULTS

Prognosis of hematologic malignancies does not predict intensive care unit or hospital mortality and almost reaches significance for 6-mo mortality (53%, 71%, and 84% rate for patients with good, intermediate, and poor prognosis, respectively, p =.058), but it determines long-term survival (p =.008). Intensive care unit, hospital, and 6-mo overall mortality rates were 38%, 61%, and 75%, respectively. Using multivariate analysis, intensive care unit mortality was best predicted on admission by respiratory failure and fungal infection, whereas hospital mortality was predicted by the number of organ failures, the bone marrow transplant status, and the presence of fungal infection. The Acute Physiology and Chronic Health Evaluation II and the Simplified Acute Physiology Score II had no prognostic value, whereas the difference of the Multiple Organ Dysfunction Score between at the time of admission and at day 5 allowed quick prediction of hospital mortality. Diseases with the poorest 6-mo prognosis were acute myeloid leukemia and non-Hodgkin lymphoma. CONCLUSION The severity of the underlying hematologic malignancies does not influence intensive care unit or hospital mortality. Short-term prognosis is exclusively predicted by acute organ dysfunctions and by a pathogen's aggressiveness. Therefore, reluctance to admit patients with nonterminal hematologic malignancies to the intensive care unit based only on the prognosis of their underlying hematologic malignancy does not seem justified.

High frequency oscillatory ventilation in adult patients with acute respiratory distress syndrome--a retrospective study

BACKGROUND

At present there are limited data about the effects of high frequency oscillatory ventilation (HFOV) in adult patients with acute respiratory distress syndrome (ARDS). This study evaluates efficacy of HFOV in such patients.

METHODS

Sixteen ARDS patients, mean age 38.2 years (range 18-76), that underwent HFOV between 1997 and 2001 were enrolled in the study and evaluated in retrospect. FIo2, arterial blood gases, mean airway pressure (mean Paw), blood pressure, heart rate and central venous pressure were recorded by 4, 8, 12, 24, 48 and 72 h of HFOV and compared to conventional mechanical ventilation (CMV) at baseline (4 h prior to HFOV).

RESULTS

On admission to the ICU, mean Simplified Acute Physiology score (SAPS II) was 40.3 (SD 12.6). Main causes of ARDS were pneumonia (9/16) and burn injuries (4/16). At baseline the patients had severe ARDS as noted by a mean lung injury score (LIS) of 3.2 (SD 0.3) and Pao2/FIo2 ratio 12.2 (SD 3.2) kPa. Within 4 h of HFOV, Pao2/FIo2 increased to 17.3 (SD 5.9) kPa (P = 0.016). Throughout HFOV, Pao2/FIo2 was significantly higher than at baseline. There were no significant changes in haemodynamic parameters. Ending HFOV after 6.6 (SD 3.2) days, survivors (n = 11) significantly reduced their Sequential Organ Failure Assessment Score (SOFA) compared to baseline. Survival at 3 months was 68.8%.

CONCLUSION

HFOV effectively improves oxygenation without haemodynamic compromise. During HFOV, the SOFA score may predict outcome.

Recent innovations in intensive care unit risk-prediction models

During the past 20 years, ICU risk-prediction models have undergone significant development, validation, and refinement. Among the general ICU severity of illness scoring systems, the Acute Physiology and Chronic Health Evaluation (APACHE), Mortality Prediction Model (MPM), and the Simplified Acute Physiology Score (SAPS) have become the most accepted and used. To risk-adjust patients with longer, more severe illnesses like sepsis and acute respiratory distress syndrome, several models of organ dysfunction or failure have become available, including the Multiple Organ Dysfunction Score (MODS), the Sequential Organ Failure Assessment (SOFA), and the Logistic Organ Dysfunction Score (LODS). Recent innovations in risk adjustment include automatic physiology and diagnostic variable retrieval and the use of artificial intelligence. These innovations have the potential of extending the uses of case-mix and severity-of-illness adjustment in the areas of clinical research, patient care, and administration. The challenges facing intensivists in the next few years are to further develop these models so that they can be used throughout the IUC stay to assess quality of care and to extend them to more specific patient groups such as the elderly and patients with chronic ICU courses.

Comparison of multiple organ dysfunction scores in the prediction of hospital mortality in the critically ill

OBJECTIVE

To compare the scales and predictive power for hospital mortality of three recent multiple organ dysfunction scores.

DESIGN

Prospective, observational, validation cohort study.

SETTING

A ten-bed medical-surgical intensive care unit in a Finnish tertiary care hospital.

PATIENTS

Among the 591 consecutive patients admitted, 520 patients who stayed >4 hrs were studied.

MEASUREMENTS AND MAIN RESULTS

Clinical and laboratory data were collected daily. Acute Physiology and Chronic Health Evaluation (APACHE) III, Multiple Organ Dysfunction Score, Logistic Organ Dysfunction score, and Sequential Organ Failure Assessment score all were calculated and compared for hospital mortality. The areas under receiver operating curves (SE) for day-1 scores were 0.825 (0.02) for APACHE III, 0.805 (0.02) for Logistic Organ Dysfunction, 0.776 (0.02) for SOFA, and 0.695 (0.02) for Multiple Organ Dysfunction Score in prediction of hospital mortality. The highest discriminative power was revealed with total maximum scores. No statistical differences existed between the total maximum scores (p values,.06 to.97). Calibration was good for all scores of day-1 multiple organ dysfunction scales and APACHE III by chi-square test (values between 10.14 and 5.42).

CONCLUSIONS

Discriminative power (ability to distinguish between patients who die and those who live) of day-1, of daily maximum, and especially of total maximum multiple organ dysfunction scores, were rather good, comparable with each other, and comparable with APACHE III in prediction of hospital mortality.

A randomized phase II trial of granulocyte-macrophage colony-stimulating factor therapy in severe sepsis with respiratory dysfunction

Granulocyte-macrophage colony-stimulating factor (GM-CSF) stimulates hemopoiesis and effector functions of granulocytes and macrophages and is involved in pulmonary surfactant homeostasis. We investigated whether GM-CSF therapy improved clinically diagnosed severe sepsis and respiratory dysfunction in critically ill patients. This randomized, double-blind, placebo-controlled phase II study added low-dose (3 mcg/kg) intravenous recombinant human GM-CSF daily for 5 days to conventional therapy in 10 patients, with a further eight patients receiving placebo. GM-CSF-treated patients showed improvement in Pa(O(2))/FI(O(2)) over 5 days (p = 0.02) and increased peripheral blood neutrophils (p = 0.08), whereas alveolar neutrophils decreased (p = 0.02). GM-CSF therapy was not associated with decreased 30-day survival or with increased acute respiratory distress syndrome or extrapulmonary organ dysfunction. GM-CSF therapy was associated with increased blood granulocyte superoxide production and restoration or preservation of blood and alveolar leukocyte phagocytic function. We conclude that low-dose GM-CSF was associated with improved gas exchange without pulmonary neutrophil infiltration, despite functional activation of both circulating neutrophils and pulmonary phagocytes. In addition, GM-CSF therapy was not associated with worsened acute respiratory distress syndrome or the multiple organ dysfunction syndrome, suggesting a homeostatic role for GM-CSF in sepsis-related pulmonary dysfunction.

Refining predictive models in critically ill patients with acute renal failure

Mortality rates in acute renal failure remain extremely high, and risk-adjustment tools are needed for quality improvement initiatives and design (stratification) and analysis of clinical trials. A total of 605 patients with acute renal failure in the intensive care unit during 1989-1995 were evaluated, and demographic, historical, laboratory, and physiologic variables were linked with in-hospital death rates using multivariable logistic regression. Three hundred and fourteen (51.9%) patients died in-hospital. The following variables were significantly associated with in-hospital death: age (odds ratio [OR], 1.02 per yr), male gender (OR, 2.36), respiratory (OR, 2.62), liver (OR, 3.06), and hematologic failure (OR, 3.40), creatinine (OR, 0.71 per mg/dl), blood urea nitrogen (OR, 1.02 per mg/dl), log urine output (OR, 0.64 per log ml/d), and heart rate (OR, 1.01 per beat/min). The area under the receiver operating characteristic curve was 0.83, indicating good model discrimination. The model was superior in all performance metrics to six generic and four acute renal failure-specific predictive models. A disease-specific severity of illness equation was developed using routinely available and specific clinical variables. Cross-validation of the model and additional bedside experience will be needed before it can be effectively applied across centers, particularly in the context of clinical trials.

D-dimer correlates with proinflammatory cytokine levels and outcomes in critically ill patients

STUDY OBJECTIVES

To determine the relationship between d-dimer (DD) and both proinflammatory and anti-inflammatory cytokine levels, and to confirm the association between DD status and outcomes in critically ill patients.

DESIGN

Prospective observational study.

SETTING

Medical ICU (MICU) of a tertiary care, academic medical center.

PATIENTS

Individuals admitted to the MICU.

INTERVENTIONS

Within 24 h of MICU admission, patients had DD status determined and interleukin (IL) levels (IL-6, IL-8, and IL-10) and tumor necrosis factor (TNF)-alpha measured. The strength of the DD level was also noted. Subjects were then monitored prospectively to determine mortality rate and the incidence of organ failure.

MEASUREMENT AND RESULTS

The study cohort included 79 patients (mean age, 65.2 years; 54.5% male patients). DD was present in 53.2% of subjects. The DD reaction was weak (1+) in 15 patients and strong (2+) in 27 patients. The TNF-alpha, IL-6, and IL-8 levels all increased in parallel with the increasing strength of the DD level. IL-10 levels did not differ based on DD status. Similarly, the severity of illness as measured by the APACHE (acute physiology and chronic health evaluation) II score was highest among those with higher DD levels: 24.7 +/- 6.2 for those with 2+ DD vs 17.2 +/- 3.1 and 11.5 +/- 2.7 for those with 1+ DD and no circulating DD, respectively (p < 0.001). For patients lacking DD, the mortality rate was 8.1%, compared to 13.3% and 55.6% for those with 1+ and 2+ DD levels, respectively (p < 0.001). No patient without DD had multisystem organ failure (MSOF) develop, while the incidence of MSOF also increased with increasing DD levels. As a screening test for mortality, the DD performed as well as the APACHE II system.

CONCLUSIONS

The coagulation system is active in critically ill patients, and DD levels correlate with activation of the proinflammatory cytokine cascade. The absence of a relationship between DD and anti-inflammatory cytokines (IL-10) suggests that the presence of DD may reflect the imbalance between proinflammatory and anti-inflammatory cytokines. DD identifies patients at increased risk for both MSOF and death.

Discriminative power on mortality of a modified Sequential Organ Failure Assessment score for complete automatic computation in an operative intensive care unit

OBJECTIVE

To evaluate the discriminative power on mortality of a modified Sequential Organ Failure Assessment (SOFA) score and derived measures (maximum SOFA, total maximum SOFA, and delta SOFA) for complete automatic computation in an operative intensive care unit (ICU).

DESIGN

Retrospective study.

SETTING

Operative ICU of the Department of Anesthesiology and Intensive Care Medicine.

PATIENTS

Patients admitted to the ICU from April 1, 1999, to March 31, 2000 (n = 524). Data from patients under the age of 18 yrs and patients who stayed <24 hrs were excluded. In the case of patient readmittance, only data from the patient's last stay was included in the study.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The main outcome measure was survival status at ICU discharge. Based on Structured Query Language (SQL) scripts, a modified SOFA score for all patients who stayed in the ICU in 1 yr was calculated for each day in the ICU. Only routine data were used, which were supplied by the patient data management system. Score evaluation was modified in registering unavailable data as being not pathologic and in using a surrogate of the Glasgow Coma Scale. During the first 24 hrs, 459 survivors had an average SOFA score of 4.5 +/- 2.1, whereas the 65 deceased patients averaged 7.6 +/- 2.9 points. The area under the receiver operating characteristic (ROC) curve was 0.799 and significantly >0.5 (p <.01). A confidence interval (CI) of 95% covers the area (0.739-0.858). The maximum SOFA presented an area under the ROC of 0.922 (CI: 0.879-0.966), the total maximum SOFA of 0.921 (CI: 0.882-0.960), and the delta SOFA of 0.828 (CI: 0.763-0.893).

CONCLUSION

Despite a number of differences between completely automated data sampling of SOFA score values and manual evaluation, the technique used in this study seems to be suitable for prognosis of the mortality rate during a patient's stay at an operative ICU.

Markers of inflammation in sepsis

Pathophysiology of sepsis is characterised by a whole body inflammatory reaction and concurrent activation of the host's anti-inflammatory mechanisms. The balance between pro- and anti-inflammatory reactions is critical for the outcome of the patient. Strongly activated phagocytes and high levels of proinflammatory cytokines occur in patients who are at risk of developing circulatory shock and multiple organ dysfunction. Extensive anti-inflammatory reaction, which is characterised by the presence of high levels of circulating anti-inflammatory cytokines and impaired innate and adaptive immune functions, renders critically ill patients prone to secondary infections. Evaluation of the immune-inflammatory status on admission to the hospital may be helpful in the early identification of patients who are bound to develop organ dysfunction. Such patients could possibly benefit from a mode of therapy aimed at modifying the course of inflammatory response. The use of inflammatory markers may also improve diagnosis of severe infection. The present review summarises the studies on markers of inflammation and immune suppression used, first, as predictors of organ dysfunction in patients with systemic inflammation, and, second, as indicators of infection in adults and neonates.

Application of modified sequential organ failure assessment score in children after cardiac surgery

OBJECTIVE

To evaluate the usefulness of the modified sequential organ failure assessment (m/SOFA) score for assessing morbidity and mortality in pediatric patients after cardiac surgery.

DESIGN

Analysis of a prospectively collected database.

SETTING

Pediatric intensive care unit of a university-affiliated hospital.

PARTICIPANTS

Consecutive pediatric patients (n = 142) undergoing cardiac surgery.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The m/SOFA score, consisting of 5 organ scores (maximum score of 20 points), was calculated on admission (initial) and at 12 and 36 hours postoperatively. An initial score of >5 points with an unchanged or upward postoperative trend predicted a higher postoperative mortality and a greater need for intensive care intervention. In neonates, sustained higher score >10 points predicted an outcome of death with a sensitivity of 100% and a specificity of 87%. Given the higher mortality related to immature organ function and a greater complexity of heart defects, the application of the m/SOFA score, a less invasive and simple way to assess organ damage, is especially suitable in neonates. The m/SOFA score would be more appropriately assessed according to the congenital heart defect or surgical procedure because the types of cardiac defect after the surgical repair affect each organ score measurement.

CONCLUSION

Application of the m/SOFA score in the early postoperative period, which reflects cumulative perioperative organ damage, would provide some direction to eventual outcomes of morbidity and mortality in patients with congenital heart defects undergoing surgery.

Negative fluid balance predicts survival in patients with septic shock: a retrospective pilot study

OBJECTIVE

We hypothesized that patients with septic shock who achieve negative fluid balance (< or =-500 mL) on any day in the first 3 days of management are more likely to survive than those who do not.

DESIGN

Retrospective chart review.

PATIENTS

Thirty-six patients admitted with the diagnosis of septic shock.

SETTING

Twelve-bed medical ICU of a 300-bed community teaching hospital.

METHODS

Medical records of 36 patients admitted to our medical ICU over a 21-month period were examined. Patients with septic shock who required dialysis prior to hospitalization were not included. A number of demographic and physiologic variables were extracted from the medical records. Admission APACHE (acute physiology and chronic health evaluation) II and daily sequential organ failure assessment (SOFA) scores were computed from the extracted data. Variables were compared between survivors and nonsurvivors and in patients who did vs those who did not achieve negative (< or = 500 mL) fluid balance in > or = 1 day of the first 3 days of management. Survival risk ratios (RRs) were used as the measure of association between negative fluid balance and survival. RRs were adjusted for age, APACHE II scores, SOFA scores on the first and third days, and the need for mechanical ventilation, by stratified analyses.

RESULTS

Patients ranged in age from 16 to 85 years with a mean (+/- SE) age of 67.4 +/- 3.3 years. The mean admission APACHE II score was 25.4 +/- 1.4, and the day 1 SOFA score was 9.0 +/- 0.8. Twenty patients did not survive; nonsurvivors had higher mean APACHE II scores than survivors (29.8 vs 20.4, respectively) and higher first day SOFA scores than survivors (10.8 vs 6.9, respectively), and they were more likely to require vasopressors and mechanical ventilation compared to patients who survived. Whereas all 11 patients who achieved a negative balance of > 500 mL on > or = 1 of the first 3 days of treatment survived, only 5 of 25 patient who failed to achieve a negative fluid balance of > 500 mL by the third day of treatment survived (RR, 5.0; 95% CI, 2.3 to 10.9; p = 0.00001). At least 1 day of net negative fluid balance in the first 3 days of treatment strongly predicted survival across the strata of age, APACHE II scores, first- and third-day SOFA scores, the need for mechanical ventilation, and creatinine levels measured at admission.

CONCLUSION

These results suggest that at least 1 day of negative fluid balance (< or = -500 mL) achieved by the third day of treatment may be a good independent predictor of survival in patients with septic shock. These findings suggest the hypothesis "that negative fluid balance achieved in any of the first 3 days of septic shock portends a good prognosis," for a larger prospective cohort study.

Scoring systems for assessing organ dysfunction and survival

Sepsis is an ongoing disease process carrying a high risk of organ failure and death. Scoring systems to determine disease severity and risk of mortality may be useful in patient management and clinical trial enrollment, although the role of either type of score in the determination of admission or discharge criteria or in decisions relating to the continuation or withholding of treatment remains controversial. General scoring systems have been developed to quantify the severity of illness and the risk of mortality in ICU patients. Ideally, these should be customized before use in patients with septic shock, but in general noncustomized models are used, and this potential limitation should be acknowledged. Prognostic scores are remarkably reliable at predicting outcome in groups of patients and give an indication of severity of disease on admission, but they are unable to provide detail on how a patient is responding to treatment or on the disease progression. Organ function scores, however, can be assessed repeatedly and used to define a patient's progress. This approach can thus be used to evaluate individual patient care, to identify patients for enrollment in clinical trials or epidemiologic analyses, and to assess morbidity measures in clinical trials of new interventions. Organ dysfunction scores are just that, descriptors of organ dysfunction, and although high values correlate well with mortality, prognostication is not their prime aim; organ dysfunction scores and outcome prediction scores should rather be viewed as complementary systems in the description of ICU populations.