M. G. Dehne

Alterations of acute phase reaction and cytokine production in patients following severe burn injury

To determine the acute immunologic reaction, mediated by cytokines, interleukines (ILs) and growth factors and the susceptibility to infections and sepsis after severe burn injury a prospective, single unit, longitudinal study of acute phase reactants and mediators who performed. After approval by the ethics committee of our hospital, we investigated the plasma concentrations of IL-2, -6, -8, -10, and -13, the soluble IL-2 receptor (sIL-2R), and the acute phase proteins procalcitonin (PCT) and C-reactive protein (CRP) at admission and every 3 days in 24 patients over a time course of 28 days after thermal injury and categorized by percent burn: < or =30% (group 1; n=12) and >30% (group 2; n=12). Shortly after burn injury we found higher concentrations of IL-2, -6, -10 and PCT in those patients >30% TBSA. During the study period, we found significant higher levels of acute phase proteins, IL-6 and -8 in patients >30% TBSA. The incidence of SIRS and MODS was three times increased in patients >30% TBSA. Our results show different patterns of cytokines and acute phase proteins in patients with different burned surface areas over a long time and continuous monitoring of a more distinct inflammatory response in these patients.

The systemic inflammatory response syndrome following cardiac surgery: different expression of proinflammatory cytokines and procalcitonin in patients with and without multiorgan dysfunctions

Cardiopulmonary bypass is associated with an injury that may cause pathophysiological changes in the form of systemic inflammatory response syndrome (SIRS) or multiple organ dysfunction syndrome (MODS). In the present study, we investigated the inflammatory response of patients with multiple organ dysfunctions following open-heart surgery. Plasma levels of cytokines (IL-1β, IL-6, IL-8, IL-18) and procalcitonin (PCT) were measured on the first four postoperative days in 12 adult male patients with SIRS and two or more organ dysfunctions after myocar-dial revascularization (MODS group), and 15 patients without organ dysfunctions (SIRS group). All cytokines (except IL-1β) and PCT were significantly elevated in MODS patients, with peak values at the first two postoperative days. The results of our study show a different expression of members of the IL-1 family following extracorporeal circulation. For the first time, we can document that IL-18 is involved in the inflammatory response and the initiation of the MODS following cardiopulmonary bypass. In addition to APACHE-II score, PCT, IL-8, and IL-18 may be used as parameters for the prognosis of patients with organ dysfunctions after cardiac surgery. Furthermore, it must be noted that the duration of the surgical procedure is one of the most important factors for the initiation of the inflammatory response.

Hydroxyethyl starch (HES) does not directly affect renal function in patients with no prior renal impairment

STUDY OBJECTIVES To examine the effects of hydroxyethyl starch (HES) on renal function. DESIGN Randomized, controlled trial. SETTING Operating theatre of a university hospital. PATIENTS 60 ASA physical status I and II male patients undergoing middle ear surgery. INTERVENTIONS Patients received either lactated Ringers solution (LRS) or one of three HES solutions. The HES solutions were administered in a dose of 15 mL/kg bodyweight (bw), the Ringers solution in a dose of 60 mL/kg bw, after induction of anesthesia over a period of one hour. MEASUREMENTS Blood and urine samples for hormone and enzyme tests were obtained at defined times before, during, and after surgery. Urine excretion, glomerular filtration rate (GFR), renal plasma flow, and routine hemodynamic parameters were measured simultaneously. MAIN RESULTS There were no significant intergroup differences regarding GFR, renal plasma flow, or tubular and glomerular integrity as measured by specific proteins and enzymes (alpha-1-microglobulin, Tamm-Horsfall-protein, immunoglobulin G, and N-acetyl-beta-D-glucosaminidase). Arginine vasopressin decreased in all groups during and following anesthesia, aldosterone and plasma renin activity decreased only in the HES groups, and angiotensin II decreased only in the HES 200/0.5 group. Central venous pressure increased during fluid administration in the LRS group and returned to baseline sooner in the HES groups. CONCLUSIONS Hydroxyethyl starch administration appears to be risk-free with regard to renal function in patients without preexisting renal dysfunction who undergo general anesthesia. The relevance of the decrease in aldosterone following HES therapy needs further investigation.

Hemodynamic effects of inhaled aerosolized iloprost and inhaled nitric oxide in heart transplant candidates with elevated pulmonary vascular resistance

OBJECTIVE An elevated pulmonary vascular resistance (PVR) is described as a predictor of postoperative right heart failure and increased mortality in patients undergoing orthotopic heart transplantation. The use of intravenous vasodilators is limited by their systemic effects. We evaluated the pulmonary and systemic hemodynamic effects of inhaled nitric oxide (NO) and inhaled aerosolized iloprost (IP) in heart transplant candidates with elevated PVR. METHODS Fourteen male heart transplant candidates due to dilative or ischemic cardiomyopathia with elevated PVR (> or = 180 dyn s cm(-5)) were included in the study. Increasing concentrations of NO (5, 10 and 30 ppm) and 50 microg aerosolized IP were administered by inhalation. Hemodynamic measurements preceded and followed administration of each agent. RESULTS Inhalation of IP, 10, and 30 ppm NO reduced PVR and mean pulmonary artery pressure (MPAP), but did not affect blood pressure or systemic vascular resistance. Comparing the effectiveness of 10 ppm NO and IP, we found a significant higher reduction of MPAP in patients treated with IP. An increase of cardiac index and stroke index could only be shown with IP-inhalation. CONCLUSIONS Inhaled iloprost induces pulmonary vasodilation which is significantly greater than the effects of 10 and 30 ppm NO. The results of our study show, that inhaled iloprost induces a reliable hemodynamic response in the evaluation of heart transplant candidates. Further advantages of iloprost inhalation are the lack of adverse reactions and toxic side effects and an easier administration. Due to this facts we recommend iloprost as a routine screening drug for vascular reactivity in HTx-candidates. Based on our results it would be of great interest to investigate the role of iloprost in management of postoperative right heart insufficiency following cardiac transplantation.

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.

Iloprost improves hemodynamics in patients with severe chronic cardiac failure and secondary pulmonary hypertension

PurposeSignificant pulmonary hypertension is a predictor of postoperative right heart insufficiency and increased mortality in patients undergoing orthotopic heart transplantation. Since the use of iv vasodilators is limited by their systemic effects, we evaluated the pulmonary and systemic hemodynamic effects of inhaled aerosolized iloprost (IP) in heart transplant candidates with elevated pulmonary vascular resistance (PVR).MethodsTwenty-nine male heart transplant candidates because of dilated or ischemic cardiomyopathy with elevated PVR were included in the study. After assessing baseline hemodynamics, 50 μg aerosolized IP were administered by inhalation.ResultsInhalation of iloprost reduced PVR index (PVRI; 416 ± 180 vs 349 ± 173 dyn·sec−1·m−2·cm−5;P < 0.01) and mean pulmonary artery pressure (MPAP; 28.6 ± 9 vs 24.2 ± 9.1 mmHg;P < 0.01), but did not affect blood pressure or systemic vascular resistance. An additional improvement of ventricular performance with an increase of cardiac index (CI; 2.8 ± 0.7 vs 2.6 ± 0.7 L·min−1m−2;P < 0.05) and a decrease of pulmonary capillary wedge pressure (PCWP; 15.6 ± 6.8 vs 12.8 ± 7.1 mmHg;P < 0.01) was observed after inhalation of IPConclusionsInhaled aerosolized iloprost effectively reduces MPAP and is accompanied by an increase in CI and stroke index. Further advantages of iloprost inhalation are the lack of adverse reactions and ease of administration. Iloprost may be a useful drug to screen for vascular reactivity in cardiac transplantation patients.RésuméObjectifL’hypertension artérielle pulmonaire élevée est un prédicteur d’insuffisance postopératoire du cœur droit et elle accroît la mortalité des candidats à la transplantation cardiaque. L’usage des vasodilatateurs iv étant limité par leurs effets généraux, nous avons évalué les effets pulmonaires et généraux de l’iloprost (IP) en inhalation aérosol chez des candidats à la transplantation cardiaque présentant une résistance vasculaire pulmonaire élevée (RVP).MéthodeVingt-neuf hommes, candidats à une transplantation cardiaque à cause d’une cardiomyopathie dilatée ou ischémique et d’une RVP élevée, ont participé à l’étude. À la suite de l’évaluation hémodynamique de base, 50 μg d’IP en aérosol ont été administrés par inhalation.RésultatsL’inhalation d’iloprost a réduit l’index de RVP (IRVP; 416 ± 180 vs 349 ± 173 dyn·sec−1·m−2·cm−5; P < 0,01) et la pression artérielle pulmonaire moyenne (PAPM; 28,6 ± 9 vs 24,2 ± 9,1 mmHg; P < 0,01), mais n’a pas affecté la tension artérielle ou la résistance vasculaire générale. Une amélioration supplémentaire de la performance ventriculaire accompagnée d’une hausse de l’index cardiaque (IC; 2,8 ± 0,1 vs 2,6 ± 0,7 L·min−1·m−2; P < 0,05) ainsi qu’une baisse de la pression capillaire pulmonaire bloquée (PCPB; 15,6 ± 6,8 vs 12,8 ± 7,1 mmHg; P < 0,01) ont été observées après l’inhalation d’IPConclusionL’iloprost en aérosol administré par inhalation réduit efficacement la PAPM. Cet effet est accompagné d’une hausse de l’IC et de l’index systolique. Les autres avantages de l’inhalation d’iloprost sont l’absence de réactions indésirables et la facilité d’administration. L’iloprost pourrait servir au dépistage de la réactivité vasculaire chez les candidats à la transplantation cardiaque.

Alterations of the cytokine network in patients undergoing cardiopulmonary bypass.

Cardiovascular surgery using extracorporeal circulation causes a systemic inflammatory response which often results in severe organ dysfunction and increased postoperative mortality. Advances in knowledge about the interactions of cytokines involved in the response to cardiopulmonary bypass (CPB) may improve the outcome of patients undergoing cardiac surgery. The purpose of our study was to investigate the fluctuations in cytokine production, during and after CPB. In 24 patients undergoing elective coronary artery bypass grafting, plasma levels of interleukins IL-2, IL-6, IL-10 and IL-12, soluble IL-2-receptor (sIL-2R), and transforming growth factor-beta (TGF-β) were measured at eight time points before, during and after CPB, using a standardized enzyme-linked immunosorbant assay technique. There was a significant increase in plasma levels of IL-10, IL-6 and TGF-β after weaning off CPB. The IL-2 plasma levels decreased after the onset of CPB until 24 h postoperatively (p < 0.05). Concentrations of sIL-2R decreased 20 min after the start of CPB until the end of the operation (p < 0.05). In the postoperative course, sIL-2R levels increased, with peak values 48 h after the end of the surgical procedure. The IL-12 levels decreased after weaning off CPB (p < 0.05) until 6 h postoperatively. The results of our study demonstrate an intraoperative-predominant immunosuppression, followed by an early postoperative immunological activation, combined with a distinct acute phase response.

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.

[Tamm-Horsfall protein, alpha-1- and beta-2-microglobulin as kidney function markers in heart surgery].

ZusammenfassungOperationen am offenen Herzen gehen in bis zu 4% der Fälle mit zeitweiligen Nierenfunktionsstörungen einher. Eine Lokalisation der Schädigung ist nur invasiv mit der Feinnadelbiopsie möglich. Die Ausscheidung des Nierentubulusproteins Tamm-Horsfall (THP) und der Mikroglobuline α-1 (α-1 MG) und β-2 (β-2 MG) wurden bei insgesamt 30 Patienten untersucht. Eine Einteilung in 2 Gruppen erfolgte nach der präoperativen Kreatinin-Clearance (ClKrea). Alle Patienten wurden vor und bis zum 2. Tag postoperativ beobachtet. Die Gruppe der präoperativ Nierengesunden umfaßte 15 Patienten (13 m/2 w, Diagnosen: 14mal ACB, 3mal Klappenersatz). Das THP zeigte einen gleichbleibenden Verlauf mit einer Korrelation von 0,7 zur ClKrea (p<0,001). α-1 MG aus dem spätdistalen Tubulus wies parallele Veränderungen auf. Bei β-2 MG wurden trotz Schwankungen eine deutliche Entwicklung zu pathologischen Werten postoperativ und eine hohe Korrelation zum α-1-MG gefunden (r= 0,76; p<0,0001). Die Gruppe II umfaßte ebenfalls 15 Patienten (13 m/2 w, Diagnosen: 9mal ACB, 4mal Klappenersatz, 4mal Kombinationseingriffe, 1mal HTX). Parallel zur ClKrea verhielt sich auch in dieser Gruppe der Verlauf des THP. α-1- und β-2-MG stiegen von 32,8 (0,73) mg als leicht pathologische Werte als Zeichen einer massiven tubulären Schädigung postoperativ stark an. Hier konnte gezeigt werden, daß Operationen am offenen Herzen häufig transiente Nierenfunktionsstörungen verursachen, besonders bei vorbestehenden Schäden. Außerdem wurde gezeigt, daß mit empfindlichen Parametern tubuläre und glomeruläre Schäden verifiziert werden können.AbstractAfter cardiac surgery, transient renal dysfunction often occurs. Regional differentiation of these processes is possible only using invasive techniques, including renal biopsy. Approximately 30 different plasma protein components have been identified in the urine of healthy individuals by means of qualitative and quantitative immunochemical methods. The detection of microalbuminuria has high diagnostic relevance for the early diagnosis of renal damage at a reversible stage. One typical urinary protein is Tamm-Horsfall protein (THp). After histochemical staining of human kidney sections, activity is seen in the loop of Henle and initial distal tubule. The assay of α-1 microglobulin (MG) in urine is considered one of the most efficient laboratory parameters for the diagnosis of tubular lesions. Serum concentrations of α-1 MG are less dependent on extrarenal changes than are those of other low-molecular-weight proteins. β-2 MG is also one of the standards used in recent years for diagnostic relevance. Urinary albumin excretion, normaly less than 30 mg per day, sometimes increases after glomerular damage. Some renal function tests are used daily in many intensive care units, e.g. creatinine clearance (CCr) or urea and sodium excretion. Renal dysfunction should, however, be further examined to localise regional damage and to seek new clinical standards in addition to the conventional tests. Methods. After obtaining the agreement of the local ethics committee, 30 patients were divided into two groups of 15 each: group I without renal dysfunction and CCr more than 60 ml/min; and group II with CCr below 60 ml/min. THp and α-1 MG were measured pre- and postoperatively after open heart surgery with the ELISA and β-2 MG with the nephelometric technique. These parameters were compared with clinical standards such as albumin excretion, blood urea nitrogen (BUN), urea clearance, and fractional sodium excretion. Results. The CCr did not change in group I from the pre- to postoperative period (81.5 to 85.1 and 91.4 ml/min), nor did excretion of THp (20.1 to 25.0 and 24.8 mg/day), correlation r=0.7; P<0.001). The elimination of α-1 and β-2 MG was significantly higher in the postoperative period in this group (α-1: 7.2 to 44.1 and 100.6 mg/day; β-2: 0.3 to 2.1 and 3.2 mg/day). In group II CCr showed pathological values (36.8 to 31.1 and 36.3 ml/min), as did simultaneous THp (13.5 to 9.7 and 12.7 mg/day). α-1 and β-2 MG values became more pathological in the postoperative period than in group I (α-1: 32.8 to 113.9 and 198.5 mg/day; β-2: 0.7 to 5.8 and 16.9 mg/day). Discussion. Measurement of the excretion of THp and α-1 and β-2 MG is a useful addition to present clinical standards for recognising early changes in renal function. The increases in the postoperative period after cardiac surgery showed tubular damage even in patients without predictive risk factors or clinical signs. In patients with renal dysfunction open heart surgery and extracorporeal circulation led to significant tubular damage.

Quantitative determination of free intracellular α-keto acids in neutrophils

For the first time, a procedure is described for the quantitative analysis of free α-keto acid content in human neutrophils (PMNs) relative to single cell number by reversed-phase fluorescence high-performance liquid chromatography. The procedure is minimally invasive and is unsurpassed in the quality of PMN separation, ease of sample preparation as well as sample stability. This method can satisfy the rigorous demands for an ultra-sensitive, comprehensive and rapid intracellular α-keto acid analysis in particularly for the surveillance of severe diseases as well as cellular or organ dysfunction.