T. Menges

Randomized, placebo-controlled trial of the anti-tumor necrosis factor antibody fragment afelimomab in hyperinflammatory response during severe sepsis: The RAMSES study

ObjectiveThis study investigated whether treatment with the anti-tumor necrosis factor-&agr; monoclonal antibody afelimomab would improve survival in septic patients with serum interleukin (IL)-6 concentrations of >1000 pg/mL. DesignMulticenter, double-blind, randomized, placebo-controlled study. SettingEighty-four intensive care units in academic medical centers in Europe and Israel. PatientsA total of 944 septic patients were screened and stratified by the results of a rapid qualitative immunostrip test for serum IL-6 concentrations. Patients with a positive test kit result indicating IL-6 concentrations of >1000 pg/mL were randomized to receive either afelimomab (n = 224) or placebo (n = 222). Patients with a negative IL-6 test (n = 498) were not randomized and were followed up for 28 days. InterventionsTreatment consisted of 15-min infusions of 1 mg/kg afelimomab or matching placebo every 8 hrs for 3 days. Standard surgical and intensive care therapy was otherwise delivered. Measurements and Main Results The study was terminated prematurely after an interim analysis estimated that the primary efficacy end points would not be met. The 28-day mortality rate in the nonrandomized patients (39.6%, 197 of 498) was significantly lower (p < .001) than that found in the randomized patients (55.8%, 249 of 446). The mortality rates in the IL-6 test kit positive patients randomized to afelimomab and placebo were similar, 54.0% (121 of 224) vs. 57.7% (128 of 222), respectively. Treatment with afelimomab was not associated with any particular adverse events. ConclusionsThe IL-6 immunostrip test identified two distinct sepsis populations with significantly different mortality rates. A small (3.7%) absolute reduction in mortality rate was found in the afelimomab-treated patients. The treatment difference did not reach statistical significance.

Is continuous cardiac output measurement using thermodilution reliable in the critically ill patient

Objective: Evaluation of continuous cardiac output monitoring based on the thermodilution technique in the critically ill. Design: Prospective clinical investigation. Setting: A surgical intensive care unit of a university hospital. Patients: Thirty‐five critically ill patients (trauma and/or sepsis patients), who needed pulmonary artery catheterization. The patients were prospectively studied according to the following groups: a) patients with a heart rate of >120 beats/min; b) those patients with a cardiac output of >10 L/min; c) patients with a cardiac output of <4.5 L/min; d) patients with a rectal temperature of >39.0°C; and e) patients with a pulmonary artery catheter inserted for >4 days. Interventions: Therapies were carried out according to modern intensive care medicine protocols by physicians who were not involved in the study. Measurements: Cardiac output was monitored continuously using a new, modified pulmonary artery catheter. This catheter has a heating filament by which energy is transmitted to the circulating blood (modified thermodilution technique). A bedside microprocessor calculated cardiac output using a new algorithm. Standard bolus thermodilution technique (10 mL of ice‐cold saline solution) was used to compare the continuous cardiac output measurement with the intermittent bolus cardiac output measurement. Main Results: A total of 404 pairs of intermittent (bolus) cardiac output and continuous cardiac output measurements were obtained from the 35 patients. The bias (mean difference between bolus cardiac output measurement and continuous cardiac output measurement) of all measurements was 0.03 ± 0.52 L/min and the 95% confidence limit (mean difference ± 2 sd) was ‐1.01/1.06 L/min. Also, continuous cardiac output measurement agreed closely with bolus cardiac output measurement (bias was 0.16 ± 0.57 L/min in the cardiac output of >10 L/min group; bias was ‐0.17 ± 0.50 L/min for the cardiac output of <4.5 L/min group). Increased temperature and prolonged length of stay did not influence the agreement of continuous cardiac output measurement with bolus cardiac output measurement (bias was 0.09 ± 0.51 L/min in the >39°C rectal temperature group). Conclusions: Continuous monitoring of cardiac output using a modified pulmonary artery catheter with a heated filament has proven to be accurate and precise in the critically ill patient when compared with the “standard” intermittent bolus thermodilution technique. The continuous monitoring technique enhances our armamentarium for more intensive monitoring of these patients under a variety of circumstances. (Crit Care Med 1994; 22:1913–1918)

Changes in blood lymphocyte populations after multiple trauma: Association with posttraumatic complications

OBJECTIVE To study the frequency of several lymphocyte subsets, circulating cytokines, and prostaglandin plasma values at their time course over a period of 14 days in severely injured trauma patients in relation to the development of sepsis and multiple organ failure (MOF). DESIGN Prospective study. SETTING An operative intensive care unit (ICU) of a university hospital. PATIENTS Sixty-eight consecutive severely injured trauma patients. INTERVENTIONS Patients were separated into patients without sepsis and MOF (group 1, n = 51), and patients who developed sepsis and MOF (group 2, n = 17) during their stay in the ICU. Therapy was adjusted to the standards of modern intensive care management by physicians who were not involved in the study. MEASUREMENTS AND MAIN RESULTS In arterial blood samples, the profile of lymphocyte subset frequencies was performed by flow cytometry and, together with interleukin (IL)-1, IL-10, tumor necrosis factor (TNF)-alpha soluble TNF-alpha receptor 1 (sTNF-alpha r1 [p55]), and prostaglandin E2 (PGE2alpha)-alpha, serially measured after arrival in the ICU (baseline value) and during the next 14 days. Mean plasma IL-1 (29.3 +/- 5.8 [SD] pg/mL), TNF-alpha (138.5 +/- 22.4 pg/mL), and soluble TNF-alpha r1 (6.1 +/- 0.3 ng/mL) values were significantly higher in group 2 patients before clinical evidence of sepsis and MOF. With the onset of severe infections in group 2 patients, IL-1, TNF-alpha, and sTNF-alpha r1 values decreased, while immunosuppressive IL-10 (191.7 +/- 29.1 pg/mL) and PGE2alpha (87.7 +/- 20.4 pg/mL) values further increased and remained elevated during the time course. Analysis of lymphocyte subsets revealed a fall in total lymphocyte levels, in CD4+ T lymphocytes, and natural killer (NK) cells, but no change in CD8+ T lymphocyte subset. Despite a marked change in the T helper (CD4+) to T suppressor (CD8+) ratio (from 1:1.72 to 1:1.10), patients without MOF (group 1) had no significant difference in any of the markers tested compared with baseline values. In addition to the inverse CD4+/CD8+ T cell ratio (from 1:1.75 to 1:0.91) and increased activated T cells, each of these markers was significantly elevated and peaked before the onset of MOF in group 2 patients. CONCLUSIONS A severely depressed cellular immune response associated with increased suppressive mediators might be closely related to the development of severe sepsis and MOF in trauma patients. Therefore, an in-depth understanding of the deficits in host defense following multiple trauma will provide the basis for therapeutic interventions.

Plasminogen-activator-inhibitor-1 4G/5G promoter polymorphism and prognosis of severely injured patients

A single base pair insertion/deletion (4G/SG) promoter polymorphism in the plasminogen-activator-inhibitor-1 (PAI-1) gene is thought to play a part in prognosis after severe trauma. We investigated the relation between outcome of severe trauma, PAI-1 concentrations, and PAP-1 genotype in 61 patients who had been severely injured. 11 (58%) of 19 patients with genotype 4G/4G did not survive, whereas only eight (28%) of 29 patients with heterozygous genotype 4G/SG, and two (15%) of 13 patients with genotype 5G/5G died. The PAI-1 4G allele is associated with high concentrations of PAI-1 in plasma and a poor survival rate after severe trauma.

Morphine inhibits NF-κB nuclear binding in human neutrophils and monocytes by a nitric oxide-dependent mechanism

Background The transcription factor NF-&kgr;B plays a pivotal role in gene expression of inflammatory mediators such as cytokines or adhesion molecules. NF-&kgr;B–mediated transcriptional activation of these genes is inhibited by nitric oxide (NO) in a variety of cells, including monocytes. Morphine mediates NO release in a naloxone antagonizable manner in monocytes and neutrophils. Methods The influence of morphine on NF-&kgr;B activation was investigated in a whole-blood flow cytometric assay. A specific antibody against the p65 subunit of NF-&kgr;B was used and detected by fluoresceine-isothiocyanate–labeled anti–immunoglobulin G. Nuclei were stained with propidium iodide. Leukocyte subpopulations were evaluated by gating on neutrophils and monocytes. The median fluorescence channel was determined. Different morphine concentrations (50 nm, 50 &mgr;m, 1 mm) and incubation intervals (10–150 min) were used. Results Morphine inhibits lipopolysaccharide-induced NF-&kgr;B nuclear binding in human blood neutrophils and monocytes in a time-, concentration-, and naloxone-sensitive–dependent manner. Similar effects were achieved with the NO donor S-nitroso-N-acetyl-pencillamine and the antioxidant N-acetyl-cysteine. The NO synthase inhibitors N&ohgr;-nitro-l-arginine-methyl-esther and N&ohgr;-nitro-l-arginine completely abolished the morphine-induced attenuation of NF-&kgr;B nuclear binding, demonstrating that the inhibitory action is mediated by NO release. Conclusion Morphine causes immunosuppression, at least in part, via the NO-stimulated depression of NF-&kgr;B nuclear binding.

Regional Hemostatic Status and Blood Requirements After Total Knee Arthroplasty With and Without Tranexamic Acid or Aprotinin

Antifibrinolytics seem to reduce postoperative blood loss after total knee arthroplasty. Few studies have shown the impact of these drugs on the mechanisms of coagulation. The purpose of this study was to examine coagulation/fibrinolysis variables as well as blood loss after total knee arthroplasty with and without antifibrinolytics in the operated limb on a regional level. Thirty-six patients were randomized into one of three groups to receive aprotinin, tranexamic acid, or no medication. We took blood samples of the femoral vein before deflating the tourniquet and after 5, 10, 30, 60, 120 min and on the first postoperative day. The implantation of a knee prosthesis in artificial ischemia caused a significant activation of coagulation and fibrinolysis in the regional circulation. Tranexamic acid and aprotinin did not cause a significant modulation of fibrinolysis variables or a significant reduction of postoperative bleeding and transfusion requirements. One of the differences in comparison to other studies was the decreased total blood loss. The use of bone cement as well as surgical hemostasis before wound closure may be regarded as reasons for this. Therefore, primarily these methods should be used because there is no increased risk of adverse drug effects.

Alterations in circulating vasoactive substances in the critically ill--a comparison between survivors and non-survivors.

ObjectiveRegulation of circulatory homeostasis is based on several factors including various circulating vasoactive substances. Whether these regulators differ between survivors and non-survivors was investigated in critically ill patients.DesignProspective study.SettingClinical investigation on a surgical intensive care unit of an university hospital.Patients60 consecutive patients suffering from trauma (n=21) or postoperative complications (n=39) were studied prospectively. The patients were divided into survivors (n=27) and non-survivors (n=33). Therapy was adjusted to the standards of modern intensive care management by physicians who were not involved in the study.Measurements and resultsEndothelin-1, atrial natriuretic peptide (ANP), vasopressin, renin, and catecholamine (epinephrine, norepinephrine) plasma levels were measured from arterial blood samples using radioimmunoassay (RIA) or high-pressure liquid chromatography (HPLC) technique on the day of admission to ICU and during the following 5 days. Various hemodynamic parameters were also monitored during that period. The non-survivors showed elevated pulmonary artery pressure (PAP: 34.1±5.4 mmHg) and pulmonary capillary wedge pressure (PCWP: 20.3±7.3 mmHg) already at the beginning of the study. Cardiac index (CI) did not differ among the groups, whereas right ventricular ejection fraction (RVEF) decreased in the non-survivors. PaO2/FIO2 decreased only in the non-survivors, whereas VO2 increased in the survivors (from 246±48 to 331±43 ml/min). Plasma levels of renin (from 206±40 to 595±81 pg/ml) and vasopressin (from 5.78±0.82 to 7.97±0.69 pg/ml) increased significantly in the non-survivors. Epinephrine and norepinephrine plasma concentrations were elevated in the non-survivors already at baseline and tremendously increased in these patients during the following days. ANP plasma levels significantly increased also only in the non-survivors (from 188±63 to 339±55 pg/ml) (p<0.05). Endothelin-1 decreased in the survivors, whereas it significantly increased in the non-survivors (from 3.62±0.68 to 9.37±0.94 pg/ml) during the study period (p<0.05). Analyses of co-variance revealed overall no significant correlation between circulating vasoactive substances and hemodynamics.ConclusionsSystemic and regional regulators of the circulation were markedly changed by critical illness. In survivors, these regulators almost normalized within the study period of 5 days, whereas in non-survivors these alterations were even aggravated. It can only be speculated whether these regulator systems were influenced by activation of various mediator systems or whether they themselves influenced the negative outcome in the non-survivors.

Plasma levels of immunoinhibitory cytokines interleukin-10 and transforming growth factor-beta in patients undergoing coronary artery bypass grafting.

OBJECTIVE Cardiovascular surgery with extracorporeal circulation causes a systemic inflammatory response, which can lead to organ failure and increased postoperative morbidity. Advances in knowledge about the interactions between markers of cellular and humoral immunity involved in the inflammatory response to cardiopulmonary bypass (CPB) may reduce the deleterious effects and improve the outcome for patients undergoing cardiac surgery. METHODS To determine the release of immunoinhibiting cytokines during CPB, we measured plasma levels of interleukin-10 (IL-10) and transforming growth factor-beta (TGF-beta) in 30 patients undergoing elective coronary artery bypass grafting. Arterial blood samples were collected at eight time points before, during and after CPB, using a standardized ELISA-technique. RESULTS Plasma IL-10 and TGF-beta increased significantly after weaning off CPB (P < 0.05) and peaked respectively at time of skin closure (IL-10, 308 +/- 180 pg/ml; TGF-beta, 1860 +/- 906 pg/ml; mean peak +/-S.D.). Postoperatively, 6 h, IL-10 decreased to 19.8 +/- 9.8 pg/ml (P < 0.05) and TGF-beta decreased to 1133 +/- 547 pg/ml (P < 0.05). CONCLUSIONS Both cytokines are major immunoregulatory factors with negative influence on T cell-mediated immunologic response. The significantly elevated levels at the end of CPB indicate that IL-10 and TGF-beta may be important factors of immunologic dysregulation following CPB.

Sepsis syndrome and death in trauma patients are associated with variation in the gene encoding tumor necrosis factor.

Objective:Patients encountering severe trauma are at risk of developing sepsis syndrome and subsequent multiple organ failure. This is often associated with fatal outcome despite survival of the initial injury. We postulate that variation of the gene coding for tumor necrosis factor (TNF)-α is associated with increased occurrence of sepsis syndrome and mortality in trauma patients. Design:Prospective cohort study; validation in an external replication sample. Setting:Tertiary academic medical center. Patients:We included 159 severely traumatized patients from a single center. Serial blood samples were analyzed for serum concentrations of TNF-α and lymphotoxin-α (LTA). We genotyped nine polymorphisms in the TNF gene and tested for an association with sepsis syndrome and outcome. Genetic associations were validated in an external replication sample (n = 76). We examined the peripheral blood transcriptome in 28 patients by whole genome-based profiling and validated the results. Interventions:None. Measurements and Main Results:Carriage of the TNF rs1800629 A allele was associated with higher TNF-α serum concentrations on the first day after trauma and during follow-up (two-sided p = 5.0 × 10−5), with development of sepsis syndrome (odds ratio 7.14, two-sided p = 1.2 × 10−6; external validation sample [n = 76]: odds ratio 3.3, one-sided p = .03), and with fatal outcome (odds ratio 7.65, two-sided p = 1.9 × 10−6). Carriage of the TNF rs1800629 A allele was associated with differential expression of genes representing stronger proinflammatory and apoptotic responses compared with carriage of the wild-type allele. Conclusions:Common TNF gene variants are associated with sepsis syndrome and death after severe injury. These findings are strongly supported by functional data and may be important for developing preemptive anti-inflammatory interventions in carriers of the risk-associated allele.

Quantitative determination of free intracellular amino acids in single human polymorphonuclear leucocytes. Recent developments in sample preparation and high-performance liquid chromatography

The described procedure allows quantitative, highly precise and reproducible analysis of free amino acid concentrations in single polymorphonuclear leucocytes (PMLs). This method is superior to previously described procedures with regard to sample size, PML separation, sample preparation and stability, as well as the chosen fluorescence high-performance liquid chromatography procedure, and can satisfy the high demands for ultra-sensitive and comprehensive amino acid analysis, especially for the continuous surveillance of severe diseases and organ dysfunction.