Luiz Monteiro da Cruz Neto

Evolutive standard base excess and serum lactate level in severe sepsis and septic shock patients resuscitated with early goal-directed therapy: still outcome markers?

PURPOSE To compare the evolution of standard base excess and serum lactate level between surviving and non surviving patients with severe sepsis and septic shock resuscitated with early goal-directed therapy. METHODS This is a retrospective study in an intensive care unit of a university tertiary hospital where 65 consecutive severe sepsis and septic shock patients were observed without any intervention in the treatment by the authors of this report. RESULTS In our study, the mortality of severe sepsis and septic shock patients was 38%. The central venous oxygen saturation of both groups was above 70% after the resuscitative period, excluding the second day of the non survivors group (69.8%). After the second day, the central venous oxygen saturation was significantly higher in the survivors group (P < .001). Standard base excess was initially low in both groups, but from the second day on, the correction of standard base excess was significantly more successful and linear in the survivor group (P < .001). Lactate levels were similar during the evolution of both groups. CONCLUSIONS Although evolutive standard base excess and serum lactate level are still outcome markers in severe sepsis and septic shock patients resuscitated with early goal-directed therapy, other studies must be performed to clarify if hemodynamic interventions based on standard base excess and serum lactate level could be reliable to improve clinical outcomes in severe sepsis and septic shock patients.

The use of sodium-chloride difference and chloride-sodium ratio as strong ion difference surrogates in the evaluation of metabolic acidosis in critically ill patients

PURPOSE Inorganic apparent strong ion difference (SIDai) improves chloride-associated acidosis recognition in dysnatremic patients. We investigated whether the difference between sodium and chloride (Na(+)-Cl(-)) or the ratio between chloride and sodium (Cl(-)/Na(+)) could be used as SIDai surrogates in mixed and dysnatremic patients. PATIENTS AND METHODS Two arterial blood samples were collected from 128 patients. Physicochemical analytical approach was used. Correlation, agreement, accuracy, sensitivity, and specificity were measured to examine whether Na(+)-Cl(-) and Cl(-)/Na(+) could be used instead of SIDai in the diagnosis of acidosis. RESULTS Na(+)-Cl(-) and Cl(-)/Na(+) were well correlated with SIDai (R = 0.987, P < 0.001 and R = 0.959, P < 0.001, respectively). Bias between Na(+)-Cl(-) and SIDai was high (6.384 with a limit of agreement of 4.463-8.305 mEq/L). Accuracy values for the identification of SIDai acidosis (<38.9 mEq/L) were 0.989 (95% confidence interval [CI], 0.980-0.998) for Na(+)-Cl(-) and 0.974 (95% CI, 0.959-0.989) for Cl(-)/Na(+). Receiver operator characteristic curve showed that values revealing SIDai acidosis were less than 32.5 mEq/L for Na(+)-Cl(-) and more than 0.764 for Cl(-)/Na(+) with sensitivities of 94.0% and 92.0% and specificities of 97.0% and 90.0%, respectively. Na(+)-Cl(-) was a reliable SIDai surrogate in dysnatremic patients. CONCLUSIONS Na(+)-Cl(-) and Cl(-)/Na(+) are good tools to disclose SIDai acidosis. In patients with dysnatremia, Na(+)-Cl(-) is an accurate tool to diagnose SIDai acidosis.

Cathelicidin LL-37 bloodstream surveillance is down regulated during septic shock

Host defense peptides are ancient weapons of the innate immunity. The human cathelicidin LL-37 protects the epithelial barrier against infection and is constitutively secreted in the bloodstream by immune cells. Current knowledge claims that LL-37 is up regulated upon infection. LL-37 can protect against bacterial infections and possesses many immunomodulatory properties. Here, we show that the human host defense peptide LL-37 is down regulated during septic shock. Furthermore, we show that these effects are not related to vitamin D serum levels, a potent inducer of LL-37 gene expression, pointing out the complex regulation of cathelicidins during septic shock.

Relationship between acid-base status and inflammation in the critically ill.

IntroductionThere is a complex interplay between changes in acid–base components and inflammation. This manuscript aims to explore associations between plasma cytokines and chemokines and acid–base status on admission to intensive care.MethodsWe conducted a prospective cohort study in a 13-bed ICU in a tertiary-care center in Brazil. 87 unselected patients admitted to the ICU during a 2-year period were included. We measured multiple inflammatory mediators in plasma using multiplex assays and evaluated the association between mediator concentrations and acid–base variables using a variety of statistical modeling approaches, including generalized linear models, multiadaptive regression splines and principal component analysis.ResultsWe found a positive association between strong ion gap (SIG) and plasma concentrations of interleukin (IL)6, 8, 10 and tumor necrosis factor (TNF); whereas albumin was negatively associated with IL6, IL7, IL8, IL10, TNF and interferon (IFN)α. Apparent strong ion difference (SIDa) was negatively associated with IL10 and IL17. A principal component analysis including SAPS 3 indicated that the association between acid–base components and inflammatory status was largely independent of illness severity, with both increased SIG and decreased SIDa (both drivers of acidosis) associated with increased inflammation.ConclusionAcid–base variables (especially increased SIG, decreased albumin and decreased SIDa) on admission to ICU are associated with immunological activation. These findings should encourage new research into the effects of acid–base status on inflammation.

Effect of Paco2 variation on standard base excess value in critically ill patients

PURPOSE The aim of this study was to investigate the impact of acute Paco(2) temporal variation on the standard base excess (SBE) value in critically ill patients. METHODS A total of 265 patients were prospectively observed; 158 were allocated to the modeling group, and 107 were allocated to the validation group. Two models were developed in the modeling group (one including and one excluding Paco(2) as a variable determinant of SBE), and both were tested in the validation group. RESULTS In the modeling group, the mathematical model including SIDai, SIG, l-lactate, albumin, phosphate, and Paco(2) had a predictive superiority in comparison with the model without Paco(2) (R(2) = 0.978 and 0.916, respectively). In the validation group, the results were confirmed with significant F change statistics (R(2) change = 0.059, P < .001) between the model with and without Paco(2). A high correlation (R = 0.99, P < .001) and agreement (bias = -0.25 mEq/L, limits of agreement 95% = -0.72 to 0.22 mEq/L) were found between the model-predicted SBE value and the SBE calculated using the Van Slyke equation. CONCLUSIONS Acute Paco(2) temporal variation is related to SBE changes in critically ill patients.

Septic shock in older people: a prospective cohort study

BackgroundSeptic shock is the first cause of death in Intensive Care Units. Despite experimental data showing increased inflammatory response of aged animals following infection, the current accepted hypothesis claims that aged patients are immunocompromised, when compared to young individuals.ResultsHere, we describe a prospective cohort study designed to analyze the immune profile of this population.ConclusionOlder people are as immunocompetent as the young individual, regarding the cytokines, chemokines and growth factors response to devastating infection.

Decreased Parathyroid Hormone Levels Despite Persistent Hypocalcemia in Patients with Kidney Failure Recovering from Septic Shock

INTRODUCTION Hypocalcemia is a common and poorly understood finding in critically ill patients. The current study was designed to assess the association of ionized calcium, vitamin D, phosphorus and Parathyroid hormone levels in a cohort of patients with and without kidney dysfunction admitted for sepsis or non-infectious causes. METHODS Prospective cohort clinical and biochemical study. RESULTS We confirmed that hypocalcemia and hypovitaminosis D are a common finding in critically ill patients. Parathyroid hormone levels significantly rise in septic shock. In the recovery phase, however, despite persistent hypocalcemia, Parathyroid hormone levels abruptly decrease in patients with kidney dysfunction, but not in patients with normal renal function. CONCLUSIONS The systemic inflammatory response syndrome probably leads to inappropriately high Parathyroid hormone levels during septic shock. In the recovery phase, Parathyroid hormone levels decrease, but calcium levels remain low, displaying evidence that the parathyroid is not responding as expected. Since Parathyroid hormone receptors and calcium-sensing receptors have been described in immune cells and other cell types, we propose that these effects may have a plethora of other deleterious effects, with important implications to the pathogenesis of septic shock.

The economic effect of extracorporeal membrane oxygenation to support adults with severe respiratory failure in Brazil: a hypothetical analysis.

Objective: To analyze the cost-utility of using extracorporeal oxygenation for patients with severe acute respiratory distress syndrome in Brazil. Methods: A decision tree was constructed using databases from previously published studies. Costs were taken from the average price paid by the Brazilian Unified Health System ( Sistema Unico de Saude; SUS) over three months in 2011. Using the data of 10,000,000 simulated patients with predetermined outcomes and costs, an analysis was performed of the ratio between cost increase and years of life gained, adjusted for quality (cost-utility), with survival rates of 40 and 60% for patients using extracorporeal membrane oxygenation. Results: The decision tree resulted in 16 outcomes with different life support techniques. With survival rates of 40 and 60%, respectively, the increased costs were R

Anion gap corrected for albumin, phosphate and lactate is a good predictor of strong ion gap in critically ill patients: a nested cohort study

=-301.00/-14.00, with a Part of a document submitted to the Brazilian Network for Health Technology Assessment (Rede Brasileira de Avaliacao de Tecnologias em Saude), Ministry of Health. ABSTRACT

Neuropeptide Downregulation in Sepsis

Objective Corrected anion gap and strong ion gap are commonly used to estimate unmeasured anions. We evaluated the performance of the anion gap corrected for albumin, phosphate and lactate in predicting strong ion gap in a mixed population of critically ill patients. We hypothesized that anion gap corrected for albumin, phosphate and lactate would be a good predictor of strong ion gap, independent of the presence of metabolic acidosis. In addition, we evaluated the impact of strong ion gap at admission on hospital mortality. Methods We included 84 critically ill patients. Correlation and agreement between the anion gap corrected for albumin, phosphate and lactate and strong ion gap was evaluated by the Pearson correlation test, linear regression, a Bland-Altman plot and calculating interclass correlation coefficient. Two subgroup analyses were performed: one in patients with base-excess <-2mEq/L (low BE group - lBE) and the other in patients with base-excess >-2mEq/L (high BE group - hBE). A logistic regression was performed to evaluate the association between admission strong ion gap levels and hospital mortality. Results There was a very strong correlation and a good agreement between anion gap corrected for albumin, phosphate and lactate and strong ion gap in the general population (r2=0.94; bias 1.40; limits of agreement -0.75 to 3.57). Correlation was also high in the lBE group (r2=0.94) and in the hBE group (r2=0.92). High levels of strong ion gap were present in 66% of the whole population and 42% of the cases in the hBE group. Strong ion gap was not associated with hospital mortality by logistic regression. Conclusion Anion gap corrected for albumin, phosphate and lactate and strong ion gap have an excellent correlation. Unmeasured anions are frequently elevated in critically ill patients with normal base-excess. However, there was no association between unmeasured anions and hospital mortality.