Raúl de Pablo

Individualized PEEP Setting in Subjects With ARDS: A Randomized Controlled Pilot Study

BACKGROUND: Low-tidal-volume ventilation may be associated with repetitive opening and closing of terminal airways. The use of PEEP is intended to keep the alveoli open. No method of adjusting the optimal PEEP has shown to be superior or to improve clinical outcomes. We conducted a pilot study to evaluate the effect of setting an individualized level of PEEP at the highest compliance on oxygenation, multiple-organ-dysfunction, and survival in subjects with ARDS. METHODS: Subjects with ARDS ventilated with low tidal volumes and limitation of airway pressure to 30 cm H2O were randomized to either a compliance-guided PEEP group or an FIO2-guided group. RESULTS: Of the 159 patients with ARDS admitted during the study period, 70 met the inclusion criteria. Subjects in the compliance-guided group showed nonsignificant improvements in PaO2/FIO2 during the first 14 days, and in 28-day mortality (20.6% vs. 38.9%, P = .12). Multiple-organ-dysfunction-free days (median 6 vs 20.5 d, P = .02), respiratory-failure-free days (median 7.5 vs 14.5 d, P = .03), and hemodynamic-failure-free days (median 16 vs 22 d, P = .04) at 28 days were significantly lower in subjects with compliance-guided setting of PEEP. CONCLUSIONS: In ARDS subjects, protective mechanical ventilation with PEEP application according to the highest compliance was associated with less organ dysfunction and a strong nonsignificant trend toward lower mortality. ClinicalTrials.gov Number NCT01119872.

Mortality in Patients With Septic Shock Correlates With Anti-Inflammatory But not Proinflammatory Immunomodulatory Molecules

Background: Mortality in patients with septic shock remains unacceptably high and the attempts to antagonize certain proinflammatory cytokines based on the results of animal model studies have failed to improve survival rates. The objective of this article is to examine the pro-/anti-inflammatory cytokine balance in patients with septic shock and its connection with mortality. Methods: Serum levels of proinflammatory cytokines (tumor necrosis factor-α [TNF-α], interleukin 1β [IL-1β], interferonγ [IFN-γ], and IL-6) and soluble cytokine antagonists (soluble TNF receptor I [sTNF-RI], sTNF-RII, and IL-1Ra) were determined on admission to the intensive care unit (ICU) and 3, 7, 14, and 28 days later in 52 patients with septic shock and in 36 healthy controls. Specific sandwich enzyme-linked immunosorbent assay (ELISA) was used for all determinations. Results: Serum levels of most of the pro- and anti-inflammatory molecules examined (TNF-α, IL-6, sTNF-RI, sTNF-RII, and IL-1 receptor agonist [IL-1Ra]) were significantly elevated on admission and during the 28-day observation period in patients when compared to controls. Notably, the anti-inflammatory mediators sTNF-RI, sTNF-RII, and IL-1Ra were better predictors of mortality. Receiver-operating characteristic (ROC) analysis revealed that sTNF-RI or sTNF-RII concentrations over 2767 or 4619 pg/mL, respectively, determined a high risk of death (sensitivity: 100%-100%, specificity: 57.1%-71.4%, area under the curve [AUC] 0.759-0.841, respectively), whereas IL-1Ra concentrations below 7033 pg/mL determined a high probability of survival (sensitivity: 60%, specificity: 100%, AUC 0.724). In addition, IFN-γ levels were significantly higher in survivors than in controls during the initial 2 weeks of observation. Conclusions: Our data show that serum cytokine disturbance patterns have prognostic significance in patients with septic shock admitted to the ICU. The pattern, defined by an early response to continuously elevated anti-inflammatory cytokine serum levels, is associated with an enhanced risk of a fatal outcome for patients.

Clinical relevance of the severe abnormalities of the T cell compartment in septic shock patients

IntroductionGiven the pivotal role of T lymphocytes in the immune system, patients with septic shock may show T cell abnormalities. We have characterised the T cell compartment in septic shock and assess its clinical implications.MethodsT lymphocytes from the peripheral blood of 52 patients with septic shock and 36 healthy control subjects were analysed on admission to the intensive care unit, baseline, and 3, 7, 14 and 28 days later. T cell phenotypes (CD3+CD4+/CD3+CD8+, CD45RA+/CD45RO+, CD62L+/CD28+) were assessed by quantitative flow cytometry.ResultsCD3+, CD3+CD4+ and CD3+CD8+ lymphocyte counts were significantly lower in patients with septic shock than control subjects. In surviving patients, CD3+CD4+ lymphocytes had normalised after 14 days, yet CD3+CD8+ numbers were still low. Non effector CD45RA+CD45RO- subsets of CD3+CD4+ and CD3+CD8+ were persistently low during patient follow up. CD3+CD8+CD28+ and CD3+CD8+CD62L+ were reduced in patients versus controls and survivors versus nonsurvivors in the first three days. A prediction receptor operative curve revealed that for the CD3+CD8+CD28+ subset, a cutoff of 136 cells/ml showed 70% sensitivity and 100% specificity for predicting death and the area under the curve was 0.84 at admission. Corresponding values for CD3+CD8+CD62L+ were 141 cells/ml, 60% sensitivity, 100% specificity and an area under the curve of 0.75.ConclusionsA severe redistribution of T lymphocyte subsets is found in septic shock patients. A different kinetic pattern of T cell subset involvement is observed in surviving and nonsurviving patients, with lower numbers of circulating CD3+CD8+CD28+ and CD3+CD8+CD62L+ associated with a better disease outcome.

Circulating sICAM-1 and sE-Selectin as biomarker of infection and prognosis in patients with systemic inflammatory response syndrome☆

BACKGROUND Vascular endothelium activation is a key pathogenic step in systemic inflammatory response syndrome (SIRS) that can be triggered by both microbial and sterile proinflammatory stimuli. The relevance of soluble adhesion molecules as clinical biomarkers to discriminate between infectious and non-infectious SIRS, and the individual patient prognosis, has not been established. METHODS We prospectively measured by sandwich ELISA, serum levels of soluble E-Selectin (sE-Selectin), soluble vascular cell adhesion molecule-1 (sVCAM-1), soluble intercellular adhesion molecule-1 (sICAM-1) and soluble intercellular adhesion molecule-2 (sICAM-2) at ICU admission and at days 3, 7, 14 and 28 in patients with sepsis and at days 3 and 7 in patients with non-infectious SIRS. RESULTS At ICU admission, sE-Selectin, sVCAM-1 and sICAM-1 in patients with infectious SIRS were significantly higher than those found in patients with non-infectious SIRS. ROC analysis revealed that the AUC for infection identification was best for sICAM-1 (0.900±0.041; 95% CI 0.819-0.981; p<0.0001). Moreover, multivariate analysis showed that 4 variables were significantly and independently associated with mortality at 28 days: male gender (OR 15.90; 95% CI, 2.54-99.32), MODS score (OR 5.60; 95% CI, 1.67-18.74), circulating sE-Selectin levels (OR 4.81; 95% CI, 1.34-17.19) and sVCAM-1 concentrations (OR 4.80; 95% CI, 1.34-17.14). CONCLUSIONS Patients with SIRS secondary to infectious or non-infectious etiology show distinctive patterns of disturbance in serum soluble adhesion molecules. Serum ICAM-1 is a reliable biomarker for classifying patients with infectious SIRS from those with non-infectious SIRS. In addition, soluble E-Selectin is a prognostic biomarker with higher levels in patients with SIRS and fatal outcome.

Role of Circulating Lymphocytes in Patients with Sepsis

Sepsis is a systemic inflammatory response syndrome due to infection. The incidence rate is estimated to be up to 19 million cases worldwide per year and the number of cases is rising. Infection triggers a complex and prolonged host response, in which both the innate and adaptive immune response are involved. The disturbance of immune system cells plays a key role in the induction of abnormal levels of immunoregulatory molecules. Furthermore, the involvement of effector immune system cells also impairs the host response to the infective agents and tissue damage. Recently, postmortem studies of patients who died of sepsis have provided important insights into why septic patients die and showed an extensive depletion of CD4 and CD8 lymphocytes and they found that circulating blood cells showed similar findings. Thus, the knowledge of the characterization of circulating lymphocyte abnormalities is relevant for the understanding of the sepsis pathophysiology. In addition, monitoring the immune response in sepsis, including circulating lymphocyte subsets count, appears to be potential biomarker for predicting the clinical outcome of the patient. This paper analyzes the lymphocyte involvement and dysfunction found in patients with sepsis and new opportunities to prevent sepsis and guide therapeutic intervention have been revealed.

Sepsis-induced acute respiratory distress syndrome with fatal outcome is associated to increased serum transforming growth factor beta-1 levels☆

BACKGROUND TGF-β1 is a promoter of pulmonary fibrosis in many chronic inflammatory diseases. TGF-β1 circulating levels in patients with sepsis-induced Acute Respiratory Distress Syndrome (ARDS) have not been established. METHODS In this prospective pilot cohort study, serum bioactive TGF-β1 concentration, determined by sandwich ELISA, was analyzed in 52 patients who fulfilled criteria for septic shock at admission and on days 3 and 7. RESULTS Of the 52 patients enrolled in the study, 46.1% fulfilled the criteria for ARDS on admission. At ICU admission, there were not statistical differences in TGF-β1 concentrations between septic shock patients with or without ARDS. After 7 days of follow-up in ICU, circulating TGF-β1 levels were significantly higher in patients with sepsis and ARDS than in those without ARDS [55.47 (35.04-79.48 pg/ml) versus 31.65 (22.89-45.63 pg/ml), respectively] (p = 0.002). Furthermore, in septic shock associated ARDS patients, TGF-β1 levels were significantly higher in nonsurvivors than in survivors [85.23 (78.19-96.30 pg/ml) versus 36.41 (30.21-55.47 pg/ml), respectively] (p = 0.006) on day 7 of ICU follow-up. CONCLUSIONS In patients with septic shock, persistent ARDS is accompanied with increased circulating TGF-β1 levels. Furthermore, ARDS patients with fatal outcome show higher TGF-β1 concentrations than survivors. These results suggest the relevance of TGF-β1 levels found in the pathogenesis of persistent sepsis-induced ARDS.

Characteristics and Outcomes of Elderly Patients Refused to ICU

Background. There are few data regarding the process of deciding which elderly patients are refused to ICU admission, their characteristics, and outcome. Methods. Prospective longitudinal observational cohort study. We included all consecutive patients older than 75 years, who were evaluated for admission to but were refused to treatment in ICU, during 18 months, with 12-month followup. We collected demographic data, ICU admission/refusal reasons, previous functional and cognitive status, comorbidity, severity of illness, and hospital and 12-month mortality. Results. 338 elderly patients were evaluated for ICU admission and 88 were refused to ICU (26%). Patients refused because they were “too ill to benefit” had more comorbidity and worse functional and mental situation than those admitted to ICU; there were no differences in illness severity. Hospital mortality rate of the whole study cohort was 36.3%, higher in patients “too ill to benefit” (55.6% versus 35.8%, P < 0.01), which also have higher 1-year mortality (73.7% versus 42.5%, P < 0.01). High comorbidity, low functional status, unavailable ICU beds, and age were associated with refusal decision on multivariate analysis. Conclusions. Prior functional status and comorbidity, not only the age or severity of illness, can help us more to make the right decision of admitting or refusing to ICU patients older than 75 years.

The predictive role of early activation of natural killer cells in septic shock

Recently, several studies about the role of natural killer (NK) cells in sepsis have been highlighted. In an earlier study, we characterized the abnormalities of circulating lymphocytes in 52 patients with septic shock during the first 28 days in the intensive care unit. Our results confirm and expand some previous reports. We found that patients who did not survive exhibited less NK cell (CD3−CD56+) depletion than survivors and that these NK cells expressed CD69+ and CD57+. These data demonstrate that NK cells are key participants in septic shock because patients who survived have more depletion and expressed less early activation and differentiation.

Functional Status and Quality of Life in Elderly Intensive Care Unit Survivors

To evaluate functional status and quality of life in elderly intensive care unit (ICU) survivors at 1‐year follow‐up.

Successful outcome of cardiopulmonary arrest with systemic thrombolysis

Massive pulmonary embolism (PE) may be the cause of cardiopulmonary arrest with a reported mortality up to 65% of cases [1]. A high index of suspicion is needed to identify this condition as the origin of cardiac arrest. Some clinical characteristics can help to identify PE as the likely cause of cardiac arrest including respiratory distress and altered mental status before the episode, age under 65, witnessed arrest and presence of pulseless electrical activity as the first rhythm [2].