Initial and delayed onset of acute respiratory failure: factors associated with development and outcome.

In a prospective observational study of 1038 adult admissions to a 31-bed medical/surgical intensive care unit (ICU), acute respiratory failure (ARF, defined as a Pao(2)/Fio(2) ratio 48 h after ICU admission) in 49 (16%). On admission, the cardiovascular sequential organ failure assessment (SOFA) score was higher in initial than in delayed onset ARF (1.1 +/- 1.5 vs 0.6 +/- 1.2, P < 0.05). High admission serum C-reactive protein concentrations (OR 1.08, 95% CI 1.04-1.12, P = 0.0001) and SOFA scores (OR 1.20, 95% CI 1.08-1.33, P = 0.0007) were the factors independently associated with initial ARF, and a low Glasgow coma scale (GCS) score (OR 1.13, 95% CI 1.04-1.21, P = 0.0018) was associated with delayed onset ARF. In initial ARF, a high SOFA score (OR 1.24, 95% CI 1.12-1.38, P = 0.0001) and a low GCS score (OR 0.89, 95% CI 0.83-0.96, P = 0.0013) on admission, and in delayed onset ARF, a low GCS score at 48 h (OR 0.67, 95% CI 0.54-0.84, P = 0.0011) were independently associated with death. The mortality rate was similar for initial and delayed onset ARF.

Body temperature alterations in the critically ill.

OBJECTIVE: To determine the incidence of body temperature (BT) alterations in critically ill patients, and their relationship with infection and outcome. DESIGN: Prospective, observational study. SETTING. Thirty-one bed, medico-surgical department of intensive care. PATIENTS: Adult patients admitted consecutively to the ICU for at least 24 h, during 6 summer months. INTERVENTIONS: None. RESULTS: Fever (BT > or =38.3 degrees C) occurred in 139 (28.2%) patients and hypothermia (BT< or =36 degrees C) in 45 (9.1%) patients, at some time during the ICU stay. Fever was present in 52 of 100 (52.0%) infected patients without septic shock, and in 24 of 38 (63.2%) patients with septic shock. Hypothermia occurred in 5 of 100 (5.0%) infected patients without septic shock and in 5 of 38 (13.1%) patients with septic shock. Patients with hypothermia and fever had higher Sequential Organ Failure Assessment (SOFA) scores on admission (6.3+/-3.7 and 6.4+/-3.3 vs 4.6+/-3.2; p<0.01), maximum SOFA scores during ICU stay (7.6+/-5.2 and 8.2+/-4.7 vs 5.4+/-3.8; p<0.01) and mortality rates (33.3 and 35.3% vs 10.3%; p<0.01). The length of stay (LOS) was longer in febrile patients than in hypothermic and normothermic (36 degrees C

Infection Probability Score (IPS): A method to help assess the probability of infection in critically ill patients.

OBJECTIVE: To develop a simple score to help assess the presence or absence of infection in critically ill patients using routinely available variables. DESIGN: Observational study of a prospective cohort of patients divided into a developmental set (n = 353) and a validation set (n = 140). SETTING: Department of intensive care at an academic tertiary care center. PATIENTS: Four hundred and ninety-three adult patients admitted to the intensive care unit for > or =24 hrs. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The presence of infection was defined using the Centers for Disease Control definitions. Body temperature, heart rate, respiratory rate, white blood cell count, and C-reactive protein concentrations were measured, and the Sequential Organ Failure Assessment score was calculated throughout the intensive care unit stay. Infection was documented in 92 of the 353 patients (26%) in the developmental set and in 41 of the 140 patients (29%) in the validation set. Univariate logistic regression was used to select significant predictors for infection. Each continuous predictor was transformed in a categorical variable using a robust locally weighted least square regression between infection and the continuous variable of interest. When more than two categories were created, the variable was separated into iso-weighted dummy variables. A multiple logistic regression model predicting infection was calculated with all the variables coded 1 or 0 allowing for relative scoring of the different predictors. The resulting Infection Probability Score consisted of six different variables and ranged from 0 to 26 points (0-2 for temperature, 0-12 for heart rate, 0-1 for respiratory rate, 0-3 for white blood cell count, 0-6 for C-reactive protein, 0-2 for Sequential Organ Failure Assessment score). The best predictors for infection were heart rate and C-reactive protein, whereas respiratory rate was found to have the poorest predictive value. The cutoff value for the Infection Probability Score was 14 points, with a positive predictive value of 53.6% and a negative predictive value of 89.5%. Model performance was very good (Hosmer-Lemeshow statistic, p =.918), and the areas under receiver operating characteristic curves were 0.820 for the developmental set and 0.873 for the validation set. CONCLUSIONS: The Infection Probability Score is a simple score that can help assess the probability of infection in critically ill patients. The variables used are simple, routinely available, and familiar to clinicians. Patients with a score <14 points have only a 10% risk of infection.

C-reactive protein levels correlate with mortality and organ failure in critically ill patients.

STUDY OBJECTIVES: C-reactive protein (CRP) is an acute-phase protein, the blood levels of which increase rapidly in response to infection, trauma, ischemia, burns, and other inflammatory conditions. Although used frequently in the ICU as a sepsis marker, the relation of CRP levels to organ damage is not well known. This study assessed the association between early serum CRP concentrations and the development of organ failure and mortality in ICU patients. DESIGN: A prospective cohort study. SETTING: A 31-bed ICU in a university hospital. PATIENTS: All 313 patients admitted to the ICU during the 4-month study period. INTERVENTIONS: None. MEASUREMENTS AND RESULTS: Patients with high CRP levels at ICU admission had more severe organ dysfunction (higher sequential organ failure assessment scores, days of renal extracorporeal support therapy), longer ICU stays, and higher mortality rates than patients with normal ICU admission CRP levels. CRP concentrations were correlated with the presence and number of organ failures. ICU admission serum CRP levels > 10 mg/dL were associated with a significantly higher incidence of respiratory (65% vs 28.8%, p < 0.05), renal (16.6% vs 3.6%, p < 0.05), and coagulation (6.4% vs 0.9%, p < 0.05) failures, and with higher mortality rates (36% vs 21%, p < 0.05) than CRP levels < 1 mg/dL. In patients with CRP concentrations > 10 mg/dL on ICU admission, a decrease in CRP level after 48 h was associated with a mortality rate of 15.4%, while an increased CRP level was associated with a mortality rate of 60.9% (relative risk, 0.25; 95% confidence interval, 0.07 to 0.91; p < 0.05). CONCLUSIONS: In a heterogeneous ICU population, elevated concentrations of serum CRP on ICU admission are correlated with an increased risk of organ failure and death. Moreover, persistently high CRP concentrations are associated with a poor outcome. Serial measurements may be helpful to identify those patients who require more aggressive interventions to prevent complications.

The Multiple Organ Dysfunction Score (MODS) versus the Sequential Organ Failure Assessment (SOFA) score in outcome prediction.

OBJECTIVE: To compare outcome prediction using the Multiple Organ Dysfunction Score (MODS) and the Sequential Organ Failure Assessment (SOFA), two of the systems most commonly used to evaluate organ dysfunction in the intensive care unit (ICU). DESIGN: Prospective, observational study. SETTING: Thirty-one-bed, university hospital ICU. PATIENTS AND PARTICIPANTS: Nine hundred forty-nine ICU patients. MEASUREMENTS AND RESULTS: The MODS and the SOFA score were calculated on admission and every 48 h until ICU discharge. The Acute Physiology and Chronic Health Evaluation (APACHE) II score was calculated on admission. Areas under receiver operating characteristic (AUROC) curves were used to compare initial, 48 h, 96 h, maximum and final scores. Of the 949 patients, 277 died (mortality rate 29.1%). Shock was observed in 329 patients (mortality rate 55.3%). There were no significant differences between the two scores in terms of mortality prediction. Outcome prediction of the APACHE II score was similar to the initial MODS and SOFA score in all patients, and slightly worse in patients with shock. Using the scores' cardiovascular components (CV), outcome prediction was better for the SOFA score at all time intervals (initial AUROC SOFA CV 0.750 vs MODS CV 0.694, p<0.01; 48 h AUROC SOFA CV 0.732 vs MODS CV 0.675, p<0.01; and final AUROC SOFA CV 0.781 vs MODS CV 0.674, p<0.01). The same tendency was observed in patients with shock. There were no significant differences in outcome prediction for the other five organ systems. CONCLUSIONS: MODS and SOFA are reliable outcome predictors. Cardiovascular dysfunction is better related to outcome with the SOFA score than with the MODS.