Plasma concentration of cytokine antagonists in patients with infection following liver resection

Lipopolysaccharide and toll-like receptor 4 in dogs with congenital portosystemic shunts

Surgical attenuation of a congenital portosystemic shunt (CPSS) results in increased portal vein perfusion, liver growth and clinical improvement. Portal lipopolysaccharide (LPS) is implicated in liver regeneration via toll-like receptor (TLR) 4 mediated cytokine activation. The aim of this study was to investigate factors associated with LPS in dogs with CPSS. Plasma LPS concentrations were measured in the peripheral and portal blood using a limulus amoebocyte lysate (LAL) assay. LPS concentration was significantly greater in the portal blood compared to peripheral blood in dogs with CPSS (P = 0.046) and control dogs (P = 0.002). LPS concentrations in the peripheral (P = 0.012) and portal (P = 0.005) blood of dogs with CPSS were significantly greater than those of control dogs. The relative mRNA expression of cytokines and TLRs was measured in liver biopsies from dogs with CPSS using quantitative PCR. TLR4 expression significantly increased following partial CPSS attenuation (P = 0.020). TLR4 expression was significantly greater in dogs that tolerated complete CPSS attenuation (P = 0.011) and those with good portal blood flow on pre-attenuation (P = 0.004) and post-attenuation (P = 0.015) portovenography. Serum interleukin (IL)-6 concentration was measured using a canine specific ELISA and significantly increased 24 h following CPSS attenuation (P < 0.001). Portal LPS was increased in dogs with CPSS, consistent with decreased hepatic clearance. TLR4 mRNA expression was significantly associated with portal blood flow and increased following surgery. These findings support the concept that portal LPS delivery is important in the hepatic response to surgical attenuation. Serum IL-6 significantly increased following surgery, consistent with LPS stimulation via TLR4, although this increase might be non-specific.

Nutrition assessment as a predictor of clinical outcomes for infants with cardiac surgery: using the prognostic nutritional index

BACKGROUND

The aim of the present study was to determine whether nutrition assessment helps predict clinical outcomes (COs) in infants who have undergone cardiac surgery.

METHODS

Study subjects were infants, aged less than 18 months, who had undergone cardiac surgery between April 2007 and August 2008. The nutrition parameters assessed include Onodera's prognostic nutritional index (PNI), height for age, weight for height, and weight for age. COs included mortality rate during hospitalization, length of stay in intensive care unit (LOS-1), length of stay in the hospital after surgery (LOS-2), and duration of mechanical ventilation support. Method-1: the correlation between nutrition parameters and COs was examined by statistical analysis. Method-2: the cutoff point of nutrition parameters was determined using the minimum P value approach.

RESULTS

The following results were obtained: Results-1: PNI was the only nutrition parameter found to be correlated with LOS-1. Results-2: the cutoff point for PNI as a predictor of LOS-1 was 55.

CONCLUSIONS

It appeared that preoperative PNI was the most influential factor on LOS-1 for infants after they underwent cardiac surgery. The PNI cutoff point 55 in infants who underwent cardiac surgery seems to be the best predictor of CO.

Immunosuppression following surgical and traumatic injury

Severe sepsis and organ failure are still the major causes of postoperative morbidity and mortality after major hepatobiliary pancreatic surgery. Despite recent progress in understanding the immune conditions of abdominal sepsis, the postoperative incidence of septic complications after major visceral surgery remains high. This review focuses on the clinical and immunological parameters that determine the risk of the development and lethal outcome of postoperative septic complication following major surgery and trauma. A review of the literature indicates that surgical and traumatic injury profoundly affects the innate and adaptive immune responses, and that a marked suppression in cell-mediated immunity following an excessive inflammatory response appears to be responsible for the increased susceptibility to subsequent sepsis. The innate and adaptive immune responses are initiated and modulated by pathogen-associated molecular-pattern molecules and by damage-associated molecular-pattern molecules through the pattern-recognition receptors. Suppression of cell-mediated immunity may be caused by multifaceted cytokine/inhibitor profiles in the circulation and other compartments of the host, excessive activation and dysregulated recruitment of polymorphonuclear neutrophils, induction of alternatively activated or regulatory macrophages that have anti-inflammatory properties, a shift in the T-helper (Th)1/Th2 balance toward Th2, appearance of regulatory T cells, which are potent suppressors of the innate and adaptive immune system, and lymphocyte apoptosis in patients with sepsis. Recent basic and clinical studies have elucidated the functional effects of surgical and traumatic injury on the immune system. The research studies of interest may in future aid in the selection of appropriate therapeutic protocols.

Circulating Cytokines, Chemokines, and Stress Hormones are Increased in Patients with Organ Dysfunction Following Liver Resection

BACKGROUND

Humoral mediators are potentially involved in the pathogenesis of postoperative complications following surgery. The aim of the present study is to evaluate the postoperative responses of circulating cytokines, chemokines, and stress hormones following liver resection, and their effects on postoperative infectious complications and organ dysfunction.

PATIENTS AND METHODS

Perioperative plasma concentrations of interleukin (IL)-6, IL-10, IL-4, IL-8, macrophage chemoattractant protein (MCP)-1, cortisol, macrophage migration inhibitory factor (MIF), and leptin were measured by immunoassays in 128 consecutive patients undergoing liver resection.

RESULTS

Forty-three patients had postoperative infection and 11 had infection-related organ dysfunction. Plasma levels of all mediators except for IL-4 increased postoperatively. Postoperative levels of IL-6, IL-10, IL-8, MCP-1, cortisol, and leptin were significantly higher in patients with organ dysfunction than in those without organ dysfunction (P < 0.05). However, postoperative MIF levels were not affected by postoperative infection or organ dysfunction. Plasma levels of IL-6, IL-10, IL-8, and MCP-1 were positively correlated with operation time (P < 0.0001) or blood loss (P < 0.0001), and higher in patients with jaundiced liver (P < 0.05). In univariate logistic regression analyses, elevated IL-6, IL-10, IL-8, and MCP-1, advanced age, large volume of blood loss, long operation time, long hepatic ischemia time, and major liver resection were significantly correlated with postoperative infection (P < 0.05). In multivariate analyses, IL-6 and IL-10 were significant predisposing factors for postoperative infection (P < 0.05), and blood loss and IL-6 for organ dysfunction (P < 0.01).

CONCLUSIONS

These results suggest that IL-6, IL-10, IL-8, MCP-1, cortisol, and leptin are released after liver resection in response to surgical stress and correlated with postoperative infection and organ dysfunction, and that of these circulating mediators, IL-6 and IL-10, have a close relationship to the complications.

Increased plasma levels of IL-6 and IL-8 are associated with surgical site infection after pancreaticoduodenectomy

OBJECTIVES

Cytokines and chemokines potentially modulate postoperative immune response. Association of circulating cytokines and chemokines with postoperative infectious complications after pancreaticoduodenectomy was evaluated.

METHODS

Plasma concentrations of interleukin (IL) 6, IL-10, IL-8, macrophage chemoattractant protein 1, heat shock protein 70, and amylase, as well as amylase levels in peritoneal exudative fluid, were measured perioperatively in 60 consecutive patients who underwent pancreaticoduodenectomy.

RESULTS

Of the 60 patients, 27 patients had surgical site infection (SSI), including peritoneal infection in all, intra-abdominal abscess in 14, and radiologically visualized pancreatic leakage in 6. Postoperative plasma levels of IL-6, IL-8, and macrophage chemoattractant protein 1, as well as peritoneal amylase levels, were significantly higher in patients with SSI than in those without SSI (P < 0.05). Nonpancreatic cancer as a histopathologic diagnosis, high pancreatic juice flow, and increased levels of IL-6 and IL-8 were independently associated with SSI (P < 0.05) in multiple logistic regression analysis. Plasma levels of IL-6 and IL-10 among patients with SSI were significantly higher in those with pancreatic leakage than in those without leakage.

CONCLUSIONS

These results suggest that, in addition to pancreatic exocrine function, IL-6 and IL-8 are associated with postoperative SSI, including pancreatic leakage after pancreaticoduodenectomy.

Bacterial translocation after cirrhotic liver resection: a clinical investigation of 181 patients

BACKGROUND

Cirrhotic patients are usually associated with a high susceptibility to infection. Although bacterial translocation from gut mucosa to mesenteric lymph node (MLN) and systemic circulation is a well-known phenomenon after hepatectomy, its role in cirrhotic patients remains unclear.

MATERIALS AND METHODS

MLN was harvested for bacterial culture before and after liver resection in 181 cirrhotic patients. The characteristics and postoperative courses of patients with positive and negative bacterial culture for MLN after hepatectomy were compared. Postoperative systemic antibiotics were administered if infectious complications occurred.

RESULTS

No bacteria were cultured in MLN before hepatectomy. Bacterial translocation (BT) to MLN after hepatectomy occurred in 36 patients (BT group). After multivariate analysis, intraoperative blood transfusion was the only independent factor that influenced bacterial translocation rates after cirrhotic liver resection. BT group patients also had higher infectious and overall complication rates, with a longer postoperative hospital stay. Among the cultured bacteriae from infected sites in BT group patients with infectious complications, only 2 patients (12.5%) had totally different bacterial species to those cultured from MLNs.

CONCLUSIONS

Bacterial translocation more often occurred after liver resection in cirrhotic patients who received intraoperative blood transfusion. Such patients had higher postoperative infectious and overall complication rates. Thus, avoidance of intraoperative blood transfusion is mandatory for cirrhotic liver resection.

Host immune responses and intestinal permeability in patients with jaundice

BACKGROUND

Systemic endotoxaemia is implicated in the development of complications associated with obstructive jaundice. The aims of these studies were to assess the systemic immune response to intervention in patients with jaundice and to compare the effects of surgical and non-surgical biliary drainage on host immune function and gut barrier function.

METHODS

In the first study, 18 jaundiced and 12 control patients were studied to assess systemic immune responses before and after intervention. In the second study, immune responses and gut barrier function were assessed following surgical and non-operative biliary decompression in 45 patients with jaundice.

RESULTS

Endotoxin antibody concentrations fell significantly in patients with jaundice immediately after surgical intervention, but not after non-operative biliary drainage. This decrease was associated with a significant increase in serum P(55) soluble tumour necrosis factor (sTNF) receptor concentration (5.3 versus 10.5 ng/ml; P < 0.001), urinary excretion of P(55) TNF receptors (21.4 versus 78.8 ng/ml; P = 0.002) and intestinal permeability (lactulose : mannitol ratio 0.032 versus 0.082; P = 0.048). Intestinal permeability was significantly increased in patients with jaundice compared with controls (0.033 versus 0.015; P = 0.002).

CONCLUSION

These data suggest that obstructive jaundice is associated with impaired gut barrier function and activation of host immune function that is exacerbated by intervention. Surgery causes an exaggerated pathophysiological disturbance not seen with non-operative biliary drainage procedures.

The soluble tumor necrosis factor receptor I is an early predictor of local infective complications after colorectal surgery

The clinical implications of increased cytokine levels after major surgery remain unclear. In this study, systemic concentration of a spectrum of cytokines, including interleukins IL-6, IL-8, IL-10, IL-1ra, and soluble tumor necrosis factor receptor-I (sTNF-RI) was examined in patients with and without postoperative septic complications following colorectal surgery. Although there were no significant changes in IL-1beta, TNF-alpha, and IL-8 serum levels during the observation period, there was a significant rise in IL-6, IL-1ra, and sTNF-RI concentrations in the entire group of patients between postoperative day 1 and 14. There were no differences between the group without and with local complications when IL-6, IL-1ra, and IL-10 were examined. The serum levels of sTNF-RI, IL-1ra, and IL-6 were found to be sensitive indicators of the pro- and anti-inflammatory response to the surgical trauma, but only sTNF-RI turned out to be a sensitive early marker of local septic postoperative complications in patients with colorectal carcinoma.

Role of L-selectin in the development of ventilator-associated pneumonia in patients after major surgery

BACKGROUND

The circulating level of soluble L-selectin (sL-selectin) has been reported to be low in adult respiratory distress syndrome and acute lung injury. This study explores the role of L-selectin in the development of ventilator-associated pneumonia (VAP) in patients undergoing major surgery.

PATIENTS AND METHODS

Thirty-four patients who underwent esophagectomy were maintained by mechanical ventilation in a surgical intensive care unit. Fourteen patients developed VAP by postoperative day (POD) 7, while 20 patients did not. The plasma levels of soluble adhesion molecules and elastase were measured serially by ELISA or EIA. The expression of L-selectin on polymorphonuclear neutrophils (PMNs) was analyzed by flow cytometry.

RESULTS

In multiple logistic regression analysis, only the preoperative plasma level of sL-selectin was significantly associated with VAP. The plasma sL-selectin level before surgery was significantly lower in the patients who developed VAP compared with the patients who did not develop VAP. After surgery, the level of sL-selectin did not change. The plasma level of soluble intercellular adhesion molecule-1 increased in the patients with and without VAP. The plasma level of soluble vascular cell adhesion molecule-1 was significantly higher in the patients with VAP. L-selectin expression on PMNs showed a peak on POD 2 in the patients without VAP, whereas it was impaired in the patients with VAP.

CONCLUSIONS

Determination of the preoperative plasma level of sL-selectin may help to identify patients at high risk for VAP after esophagectomy.

Increased hepatosplanchnic inflammation precedes the development of organ dysfunction after elective high-risk surgery

This study investigated the relationship of the hepatosplanchnic production and uptake of inflammatory mediators, hepatosplanchnic perfusion, and outcome during major abdominal surgery to evaluate the hypothesis that regional production of inflammatory mediators precedes the development of hepatic dysfunction. This retrospective analysis of data and blood samples collected during a randomized controlled clinical trial included high-risk surgical patients undergoing major abdominal surgery in a 24-bed university-afilliated intensive care unit. Patients were divided into a subgroup that developed hepatic dysfunction (HD+) postoperatively and a subgroup without hepatic dysfunction (HD-). Hepatic vein and arterial plasma levels of IL-6, IL-8, s-E-selectin, s-ICAM-1, and the TNF-receptors 55 and 75 were measured, and the flux was calculated by multiplying the difference in hepatic vein minus arterial levels of the mediators by the hepatosplanchnic flow. Systemic (thermodilution) and total hepatosplanchnic blood flow (using indocyanine green [ICG]-dilution method) and gastric intramucosal pH (pHi) were assessed preoperatively, 4, 24, and 36 h postoperatively. Of a total of 26 patients, 6 patients developed hepatic dysfunction after their abdominal surgery (mean 6 days postoperatively). The number of sepsis-related deaths and postoperative days on the ventilator were significantly higher in this group. A higher production of IL-8, TNF-receptor-75 and 55 in the hepatosplanchnic area in the HD+ subgroups was found, which preceded the development of organ dysfunction (P = 0.04, P = 0.02, and P = 0.02, respectively). Moreover, the uptake of s-ICAM-1 was significantly increased in this subgroup. Furthermore, total hepatosplanchnic blood flow was significantly higher and pHi was significantly lower in the HD+ group, whereas global hemodynamic data were similar in the two subgroups. In conclusion, the development of postoperative organ dysfunction is preceded by an increased regional inflammatory response, indicated by an increased soluble TNF-receptor shedding and IL-8 production from the hepatosplanchnic area together with an increased uptake of s-ICAM-1. Moreover, an increased total hepatosplanchnic blood flow with intramucosal acidosis was associated with this regional inflammatory response.

Anti-inflammatory response in patients with obstructive jaundice caused by biliary malignancy

BACKGROUND

Obstructive jaundice potentially modulates the host defense mechanism resulting in perioperative infection. It has been reported that a systemic inflammatory response occurs in patients with obstructive jaundice. An anti-inflammatory response was studied in 29 jaundiced patients undergoing biliary drainage.

RESULTS

Plasma concentrations of interleukin (IL)-10, soluble tumor necrosis factor receptor (STNFR) p55, STNFR p75, IL-1 receptor antagonist (IL-1ra), IL-6 and soluble CD14 (sCD14) were measured by using immunoassay. Plasma concentrations of IL-10, STNFR p55, STNFR p75, IL-1ra, IL-6 and sCD14 were significantly higher in jaundiced patients than in the controls (P < 0.01). After biliary drainage, the concentrations of IL-10, the three cytokine antagonists, and IL-6 decreased significantly (P < 0.05). The sCD14 concentration did not decrease. At the time of drainage, the concentrations of STNFR p55 and STNFR p75 were significantly higher in 10 patients with positive bile cultures than in 19 patients with negative bile cultures (P < 0.05). Bile cultures became positive 14 days after drainage in 10 patients, and remained negative in nine. The concentration of STNFR p55 before drainage was significantly higher in the former group (P = 0.05). The plasma concentrations of IL-10 and STNFRs were significantly correlated with the IL-6 concentration, body temperature and the white blood cell count (P < 0.05). Serum total bilirubin levels did not affect plasma levels of anti-inflammatory mediators, and sCD14.

CONCLUSION

Jaundiced patients exhibited an anti-inflammatory immune response that potentially modulates the host defense mechanism and results in anergy and increased susceptibility to infection. Biliary infection may be one of the major stimuli of the immune response.

Leucocyte activation markers in clinical practice

The response against tissue injury and infection begins with the early activation of molecular and cellular elements of the inflammatory and immune response. Severe tissue injury, necrosis, and infection induce imbalanced inflammation associated with leukocyte over-stimulation and excessive or dysregulated release of cellular mediators. Clinical and experimental studies have shown that these mediators are directly related to progressive post-injury complications. Persistent increased levels of pro-inflammatory mediators produce tissue injury. Excessive production and activity of anti-inflammatory mediators cause anergy and/or immune dysfunction with increased susceptibility to infection. Leukocyte activation is assessed by cell surface phenotype expression, cellular mediators determination, or by measuring functional responses using isolated cells. Potential routine clinical uses are: evaluation of severity and prognosis in critically ill patients, immunomonitoring of sepsis, and detection of tissue injury, necrosis, and infection. In practice, the determination of cellular activation markers is restricted by a limited number of automated methods and by the cost of reagents. The availability of flow cytometry and immunoassay automated systems can contribute to a wider use in practice. Here we review the immunopathophysiology of polymorphonuclear neutrophil, monocyte, macrophage, and lymphocyte activation in response to tissue injury and infection. In addition, laboratory methods for their determination, and clinical applications in practice, are discussed.