Jörg Hambsch

Cytometric Bead Array to Measure Six Cytokines in Twenty-Five Microliters of Serum

Infections and sepsis are among the most common reasons for neonatal morbidity and mortality. Early diagnosis is difficult because clinical presentation is highly variable and signs are often subtle and common to a variety of conditions. Among the proposed early indicators of infection and sepsis are serum concentrations of interleukin (IL)-6, IL-8, and IL-10. It is believed that IL-8 is a sensitive indicator of infection and that high concentrations of IL-6 and IL-10 are indicators of sepsis and predictors of mortality (1)(2)(3). The concentrations of each of these cytokines in serum vary by several orders of magnitude (1)(2)(3). Literature-reported cutoff values for IL-8 are >70 ng/L (2) or >18 ng/L (1) for infection, and values >10 000 ng/L have been reported (1). IL-6 >175 ng/L is predictive of sepsis, and values >747 ng/L are predictive for pneumonia (3). IL-6 is also believed to be predictive of necrotizing enterocolitis (3). IL-10 >420 ng/L correlates with neonatal death (3). The ELISAs commonly used for cytokine detection require 50–100 μL of serum (∼100–200 μL of peripheral blood in the neonate) per cytokine. To determine the stage of an infection, measurement of several cytokines at multiple time points can be of importance (3). Combining pro- and antiinflammatory cytokines in a single assay yields an overall view on the patient’s inflammatory status; may allow differentiation among infection, sepsis, and enterocolitis; and thus may improve diagnostic accuracy. In neonates, however, particularly preterm neonates, such combined measurements are often hampered by lack of sufficient obtainable blood (1). Furthermore, although the ELISAs are adequate for measuring these cytokines, they often require multiple dilutions to cover a wide concentration range because …

Cardiopulmonary bypass-induced increase of serum interleukin-10 levels in children

R E F E R E N C E S 1. Buckley MG, Sethi D, Markandu ND, Sagnella A, Singer DRJ, MacGregor GA. Plasma concentrations and comparisons of brain natriuretic peptide and atrial natriuretic peptide in normal subjects, cardiac transplant recipients and patients with dialysis-independent or dialysis-dependant chronic renal failure. Clin Sci 1992;83:437-44. 2. Geny B, Piquard F, Follenius M, Thiranos JCL, Charpentier A, Epailly E, et al. Endothelin participates in increased circulating atrial natriuretic peptide early after human heart transplantation. J Heart Lung Transplant. In press. 3. Ationu A, Burch M, Singer D, Littleton P, Carter N. Cardiac transplantation affects ventricular expression of brain natriuretic peptide. Cardiovasc Res 1993;27:188-91. 4. El Gamel A, Campbell C, Yonan N, Keevil B, Warburton R, Woodcock A, et al. Atrial natriuretic peptide release after cardiac transplantation. J Thorac Cardiovasc Surg 1996;112: 1128-9. 5. Lang CC, Prasad N, McAlpine HM, Macleod C, Lipworth BJ, MacDonald TM, et al. Increased plasma levels of brain natriuretic peptide in patients with isolated diastolic dysfunction. Am Heart J 1994;127:1635-6.

Pulmonary artery sling: reimplantation versus antetracheal translocation

BACKGROUND We compared two repair techniques for pulmonary artery sling. The first comprised detachment of the aberrant left pulmonary artery from the right pulmonary artery and its implantation into the main pulmonary artery, and the second, translocation of the left pulmonary artery anterior to the trachea (without implanting it into the main pulmonary artery), resection of tracheal stenosis, and end-to-end reconstruction of the trachea. METHODS Five symptomatic infants (3 boys and 2 girls; median age 5 months; range, 3 weeks to 11 months) with pulmonary artery sling were operated on through a median sternotomy with aid of cardiopulmonary bypass. In 3 patients, the left pulmonary artery was transected from the right pulmonary artery and implanted into the main pulmonary artery. In addition, the anterior trachea was augmented with a pericardial patch (n = 2). In the remaining 2 patients, associated tracheal stenosis was resected, the left pulmonary artery was translocated anterior to the trachea, and the trachea was reconstructed. RESULTS All 5 infants survived the operation. The 3 patients in whom the left pulmonary artery was implanted into the main pulmonary artery had an uncomplicated postoperative course. All 3 patients, at a follow-up of 10 months to 7.9 years, were free of symptoms; the left pulmonary artery was documented to be widely patent. The remaining 2 patients in whom the left pulmonary artery was translocated anterior to the trachea could not be extubated. In both patients the distal trachea was compressed anteriorly by the left pulmonary artery. One of these patients died at 1 week postoperatively secondary to tracheal dehiscence. In the other patient, the left pulmonary artery was implanted into the main pulmonary artery with good result; at a follow-up of 3.9 years, mild residual stridor has persisted. CONCLUSIONS In pulmonary artery sling, implantation of the aberrant left pulmonary artery into the main pulmonary artery, if necessary combined with anterior tracheoplasty, reliably eliminates tracheal and esophageal compression and maintains antegrade flow into the left pulmonary artery. Translocation of the left pulmonary artery anterior to the trachea without implanting it into the main pulmonary artery is not favored because that might result in anterior compression of the trachea. In addition, we are concerned about growth of the circumferential tracheal anastomosis in neonates and infants.

Transient Th1/Th2 disbalance indicates postoperative effusions and edema after cardiopulmonary bypass in children.

Cardiac surgery with cardiopulmonary bypass (CPB) induces substantial release of IL‐10, indicating increased Th2 cell response. Therefore, in this study, we wanted to verify if this response is due to CPB or surgical trauma, and to study its relation to postoperative effusions and edema (POEE) in children.

Urgency of operation in infracardiac total anomalous pulmonary venous connection

BACKGROUND Because the tendency for pulmonary venous obstruction in the infracardiac type of total anomalous pulmonary venous connection may be partially dependent on the connection of the descending vein to the portal vein, the inferior vena cava, or one of their tributary vessels, we reviewed our surgical experience with various subtypes of infracardiac total anomalous pulmonary venous connection. METHODS The urgency of operation in 4 neonates with infracardiac total anomalous pulmonary venous connection was reviewed. RESULTS Two patients with pulmonary venous obstruction in whom the descending vein connected to the portal vein were operated on immediately with successful outcome. One patient who had become critically ill after the ductus venosus had closed died before operation could be undertaken. One patient in whom the descending vein connected to the left hepatic vein was operated on electively with successful outcome. CONCLUSIONS In hemodynamically stable patients with no clinical or echocardiographic signs of pulmonary venous obstruction, some form of differentiation with regard to urgency of operation may be appropriate. When the descending vein connects to the inferior vena cava or a hepatic vein, the operation may be performed on a semi-elective basis. In contrast, when the descending vein connects to the portal vein or the ductus venosus, operation should generally not be delayed because of the high likelihood of obstruction.

Protein‐losing enteropathy after fontan surgery: Is assessment of risk patients with immunological data possible?

Protein‐losing enteropathy (PLE) is a late complication of the Fontan type surgery for univentricular heart characterized by massive enteric protein loss. The pathogenesis of PLE is not fully understood, and it is unclear why the onset of PLE varies widely and occurs months or even years after surgery. Besides characteristic laboratory findings, a typical cellular feature concerns the almost selective loss of CD4+ lymphocytes at an only slightly changed CD8+ lymphocyte count. The present pilot study aimed to test whether immunological or laboratory parameters differ in patients at risk for PLE.

Neutrophil Adhesion Molecule Expression and Serum Concentration of Soluble Adhesion Molecules during and after Pediatric Cardiovascular Surgery with or without Cardiopulmonary Bypass

Background Increased neutrophil activation by cardiopulmonary bypass (CPB) during cardiovascular surgery is thought to be responsible for postoperative complications. In children, the contribution of cardiovascular surgery alone to this response is not well-characterized. Methods Children undergoing surgery with CPB (CPB group, n = 35) and without CPB (control, n = 22) were studied (age, 3–17 yr). Blood was drawn 24 h preoperatively before medication, after anesthesia, after connection to CPB, at reperfusion, 4 h to 2 days after surgery, at discharge, and months after surgery. Neutrophil antigen expression and serum concentration of adhesion molecules, interleukin 8, and C5a (fragment of C5 complement) were analyzed by flow cytometry and enzyme-linked immunosorbent assay, respectively. Results With and without CPB, anesthesia and surgery induced decreased LFA-1 (CD11a–CD18), Mac-1 (CD11b–CD18), CD45, and CD54 (intercellular adhesion molecule 1) surface expression and sICAM-1 serum concentrations (all P < 0.001). sL-selectin serum concentration decreased with CPB (P < 0.001) but was not significantly altered in the control. In contrast, CD62L expression increased during CPB (P < 0.001). The time course of all analyzed markers was not significantly different between CPB and control, with the exception of sL-selectin (P = 0.017). One-day preoperative baseline values were reached days to months after surgery. Interleukin 8 and C5a serum concentrations increased after surgery in both the CPB group and the control group. Conclusions Pediatric cardiovascular surgery leads to reduced adhesiveness and activity of circulating neutrophils. This reduction is more pronounced and sustained with CPB. These data may be useful in the assessment of novel therapeutic strategies.

Repair of Complex Unroofed Coronary Sinus by Anastomosis of Left to Right Superior Vena Cava

An extracardiac repair technique is described for the anomalously connecting left superior vena cava in complex unroofed coronary sinus syndrome. In this technique, the left superior vena cava is divided distally and is anastomosed to the right superior vena cava in an end-to-side fashion; in addition, the intracardiac anomalies are corrected. The main advantage of this technique consists of avoidance of the various disadvantages of construction of a complex intraatrial baffle.

Inflammation and Immune Suppression following Protein Losing Enteropathy after Fontan Surgery Detected by Cytomics

Protein losing enteropathy (PLE), the enteric loss of proteins, is a potential late complication after total cavopulmonary connection (TCPC - Fontan circulation) surgery. PLE etiology is poorly understood, but immunological factors seem to play a role. This study aimed to gain insight into immune phenotype alterations following post- TCPC PLE. Patients and Methods: Patients were studied over a period of up to 5 years after surgery. During routine follow-up, blood samples of TCPC patients without (n = 21) and with manifest PLE (n = 12) and of age-matched healthy children (control, n = 22) were collected. Routine laboratory, immune phenotype and serological parameters were determined. Results: Following PLE the immune phenotype dramatically changed with signs of acute inflammation (increased neutrophil and monocyte count, C-reactive protein, serum IL-8 and complement activation). In contrast, the lymphocyte count (NK cells, αβ T cell receptor-positive (TCR+) CD4+ cells, αβ TCR+ CD8+ cells) decreased (60-80%, p < 0.001). The residual T cells had elevated CD25 (IL-2R) and CD69 expression. In PLE patients unique cell populations with CD3+ αβ/γδ TCR- and αβ TCR+ CD4- CD8- double negative phenotype were present in increased frequencies. Conclusions: Our studies show for the first time a dramatically altered leukocyte phenotype, the appearance of double negative cells and the alteration of serum compounds after PLE in TCPC patients. These alterations resemble to changes in autoimmune diseases such as systemic lupus erythematosus and celiac disease. We conclude that autoimmune processes may play a role in the etiology and pathophysiology of PLE.

Modulation of the cellular and humoral immune response to pediatric open heart surgery by methylprednisolone.

With the intention to reduce overshooting immune response, glucocorticoids are frequently administered perioperatively in children undergoing open heart surgery. In a retrospective study we investigated extensively the modulation of the humoral and cellular immune response by methylprednisolone (MP).