Immunosuppressive effect of surgery

Surgical Science and the Evolution of Critical Care Medicine

Surgical science has driven innovation and inquiry across adult and pediatric disciplines that provide critical care regardless of location. Surgically originated but broadly applicable knowledge has been globally shared within the pages Critical Care Medicine over the last 50 years.

Clinical Significance of Hepatectomy for Hepatocellular Carcinoma Associated with Extrahepatic Metastases

BACKGROUND

This study evaluated the prognosis of hepatocellular carcinoma (HCC) patients with extrahepatic metastases who can undergo hepatectomy.

METHODS

A total of 32 patients who underwent hepatectomy for HCC with extrahepatic metastases, including lymph node and/or distant metastases were recruited for this study.

RESULTS

Fourteen patients had lymph node metastasis only, 16 had distant metastasis only, and 2 had both metastasis types during preoperative diagnosis. The 3-year overall survival (OS) rate of all patients was 17.9%, and the median survival time (MST) was 11.8 months. Univariate analysis revealed that intrahepatic maximal tumor size, intrahepatic tumor number, and intrahepatic tumor control after hepatectomy were significant factors influencing OS (p < 0.05). Multivariate analysis revealed that independent risk factors for OS were intrahepatic maximal tumor size and intrahepatic tumor number (p < 0.05). The MST and 3-year OS rate of patients with maximal tumor size <100 mm and intrahepatic tumor number ≤2 were 39.0 months and 51.9%, respectively.

CONCLUSIONS

Hepatectomy is not recommended for HCC patients with extrahepatic metastasis with ≥3 intrahepatic tumors, even when all intrahepatic tumors can be eliminated via hepatectomy. Aggressive surgery may be justified for HCC patients with ≤2 intrahepatic tumors and maximal tumor size <100 mm, irrespective of vascular invasion.

Production of Leukocyte Migration Inhibition Factor by Lymphocytes of Larynx Cancer Patients Stimulated by Laryngeal Carcinoma Solubilized Membrane Antigens

The production of leukocyte migration inhibition factor (LIF) from lymphocytes after stimulation with 3 M KCl soluble tumor and normal mucosa extracts was investigated in 30 patients with laryngeal carcinoma at different development stages and in 30 normal donors. The experiments were performed in heterologous and autologous systems. In heterologous systems 3 M KCl tumor extracts induced LIF production by heterologous lymphocytes from patients in 91 % of the cases, and normal mucosa extracts induced LIF production by heterologous lymphocytes from patients in 73 % of the cases and from normal donors in 90 % of the cases. In autologous systems 3 M KCl tumor extracts induced LIF production by autologous lymphocytes from the same patients in 65 % of the cases, whereas the normal laryngeal mucosa extracts induced LIF production by the same autologous lymphocytes in the 6 % of the cases. The high positivity percentage of the test in heterologous systems could be related to differences in the major histocompatibility complex. The 65 % test positivity in autologous systems using tumor extracts could be related to the presence of tumor associated antigens.

Hepatectomy leads to loss of TRAIL-expressing liver NK cells via downregulation of the CXCL9-CXCR3 axis in mice

Liver-resident natural killer (NK) cells express TNF-related apoptosis-inducing ligand (TRAIL), a critical molecule for NK cell-mediated tumor cell killing. We previously reported that TRAIL expression in liver NK cells decreases markedly after hepatectomy; however, the mechanism underlying this drastic alteration remains unknown. In this study, we assessed the role of chemokine signaling in liver-resident NK cells during the perioperative period of hepatectomy. The expression levels of various chemokine receptors on liver-resident NK cells and their associations with TRAIL expression were analyzed by flow cytometry. The expression of various intrahepatic chemokines/cytokines was analyzed after 70% hepatectomy in mice by quantitative RT-PCR and flow cytometry. We further investigated whether polyinosinic—polycytidylic acid (poly I:C)-induced NK cell activation could ameliorate TRAIL expression in the liver after 70% hepatectomy in CXCR3^-/- and wild-type mice. TRAIL⁺ NK cells strongly and exclusively expressed CXCR3, and the expression of its ligand CXCL9 was significantly decreased in the liver after hepatectomy. The kinetics of hepatic CXCL9 expression resembled the changes in hepatic TRAIL⁺ NK cells after hepatectomy. Among liver-resident mononuclear cells, CXCL9 was predominantly secreted by macrophages in response to interferon-γ stimulation. Although the administration of poly I:C, an inducer of interferon-γ, increased hepatic CXCL9 levels in both CXCR3^-/- and wild-type mice even after hepatectomy, only wild-type mice exhibited the recovery of TRAIL expression on NK cells. Partial hepatectomy remarkably reduced the proportion of TRAIL-expressing NK cells in the liver via the downregulation of the CXCL9–CXCR3 axis in mice. These findings extend our knowledge of the factors contributing to hepatocellular carcinoma recurrence after hepatectomy.

Particle radiotherapy, a novel external radiation therapy, versus liver resection for hepatocellular carcinoma accompanied with inferior vena cava tumor thrombus: A matched-pair analysis

BACKGROUND

Hepatocellular carcinoma accompanied with inferior vena cava tumor thrombus carries a dismal prognosis, and the feasibility of local treatment has remained controversial. The present study aimed to compare the outcomes of particle radiotherapy and liver resection in patients with hepatocellular carcinoma with inferior vena cava tumor thrombus.

METHODS

Thirty-one and 19 patients, respectively, underwent particle radiotherapy and liver resection for hepatocellular carcinoma with inferior vena cava tumor thrombus. A matched-pair analysis was undertaken to compare the short- and long-term outcomes according to tumor stage determined using the tumor-node-metastasis classification.

RESULTS

Both stages IIIB and IV (IVA and IVB) patients were well-matched for 12 factors, including treatment policy and patient and tumor characteristics. The median survival time of matched patients with stage IIIB tumors in the particle radiotherapy group was greater than that in the liver resection group (748 vs 272 days, P = .029), whereas no significant difference was observed in the median survival times of patients with stage IV tumors (239 vs 311 days, respectively). There were significantly fewer treatment-related complications of grade 3 or greater in the particle radiotherapy group (0%) than in the liver resection group (26%).

CONCLUSION

Particle radiotherapy is potentially preferable in hepatocellular carcinoma patients with stage IIIB inferior vena cava tumor thrombus and at least equal in efficiency to liver resection in those with stage IV disease, while causing significantly fewer complications. Considering the relatively high survival and low invasiveness of particle radiotherapy when compared to liver resection, this approach may represent a novel treatment modality for hepatocellular carcinoma with inferior vena cava tumor thrombus.

Regression of Pineal Lesions: Spontaneous or Iatrogenic? A Case Report and Systematic Literature Review

BACKGROUND

Tumors arising from the pineal region account for approximately 1% of intracranial neoplasms. We present a case of a previously healthy 5-year-old boy with an acute onset of headache. A magnetic resonance imaging (MRI) scan showed a pineal mass with aqueduct compression. The patient was scheduled for tumor resection. An endoscopic third ventriculostomy was performed in advance for the treatment of hydrocephalus. Afterwards, MRI showed a relevant regression of the pineal mass without specific treatment. Consequently, surgery was cancelled and further MRI follow-up showed a regression of the mass and a constant tumor mass over a period of 30 months. Spontaneous regression of malignant tumors is a rare phenomenon with an incidence of 1 of 60,000-100,000 cases. Only a few cases with spontaneous regression of pineal tumors have been reported.

METHODS

We performed a systematic literature review according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) guidelines on spontaneously regressing pineal lesions and found 13 cases in the literature.

RESULTS

Six hypotheses for explaining tumor regression were found, comprising treatment with steroids, effects of diagnostic irradiation, treatment of hydrocephalus, pineal apoplexy, surgical trauma, and immunologic mechanisms. None of these mechanisms was evidentiary. However, in all reported cases, some kind of treatment (e.g. treatment of hydrocephalus, application of steroids, and so on) has been performed before tumor regression.

CONCLUSIONS

The clinician has to bear in mind that regression of pineal tumors might be triggered by use of steroids, for example, and in cases of improvement of the patient's presenting symptoms, new MRI scans should be performed.

Prognostic value of circulating cytokines on overall survival and disease-free survival in cancer patients

Through their tumor-promoting and/or tumor-suppressive properties, cytokines can influence progression of cancer. We systematically reviewed the current literature on the prognostic value of the circulating cytokines IL-1α/β, IL-6, IL-8, IL-10, IL-12, TNF-α, TGF-β and IFN-γ to predict overall and disease-free survival in any type of cancer patients. PubMed was systematically searched and based on eligibility assessment using our five criteria of the Reporting Recommendations for Tumor Marker Prognostic Studies (REMARK) checklist, six unique studies were reviewed. Elevated IL-6 and IL-10 levels seem independently associated with worse prognosis in terms of overall and disease-free survival. The prognostic value of IL-1α/β, IL-8, IL-12, TNF-α, TGF-β and IFN-γ could not be demonstrated. The small number of selected studies underlines the need for large well-designed prospective studies, using the REMARK checklist as a guideline, to determine which cytokines have prognostic value on survival in cancer patients.

Systemic immune response after laparoscopic and open cholecystectomy

The laparoscopic approach is thought to reduce the postoperative immunologic and metabolic effects of an open operation. This study was designed with the aim of comparing the systemic immune response after laparoscopic and open cholecystectomy. Seventeen patients with gallbladder stones were assigned to undergo either a laparoscopic (n = 9) or open (n = 8) approach. The postoperative immune response was assessed by measuring the serum levels of soluble Fas (sFas), soluble L-selectin (sL-selectin), and transforming growth factor-beta1 (TGFbeta1) preoperatively and 2 hours, 1 day, and 2 days postoperatively. Both approaches resulted in a significant decrease in sFas levels 1 and 2 days postoperatively. The open approach evoked a transient increase in sL-selectin levels 2 hours postoperatively. Moreover, the open approach resulted in a persistent, significant increase in TGFbeta1 levels postoperatively. Comparison of open versus laparoscopic cholecystectomy has shown no significant difference in sFas level and a statistically significant increase of sL-selectin (within 2 hours) and TGFbeta levels after open surgery. Although both laparoscopic and open cholecystectomy evoked an alteration of the systemic immune response, our data showed that such immune response may be less after the laparoscopic approach.

Antioxidant-enriched enteral nutrition and immuno-inflammatory response after major gastrointestinal tract surgery

Major surgery induces an immuno-inflammatory response accompanied by oxidative stress that may impair cellular function and delay recovery. The objective of the study was to investigate the effect of an enteral supplement, containing glutamine and antioxidants, on circulating levels of immuno-inflammatory markers after major gastrointestinal tract surgery. Patients (n 21) undergoing major gastrointestinal tract surgery were randomised in a single-centre, open-label study. The effects on circulating levels of immuno-inflammatory markers were determined on the day before surgery and on days 1, 3, 5 and 7 after surgery. Major gastrointestinal surgery increased IL-6, TNF receptor 55/60 (TNF-R55) and C-reactive protein (CRP). Surgery reduced human leucocyte antigen-DR (HLA-DR) expression on monocytes. CRP decrease was more pronounced in the first 7 d in the treatment group compared with the control group. In the treatment group, from the moment Module AOX was administered on day 1 after surgery, TNF receptor 75/80 (TNF-R75) level decreased until the third post-operative day and then stabilised, whereas in the control group the TNF-R75 level continued to increase. The results of the present pilot study suggest that enteral nutrition enriched with glutamine and antioxidants possibly moderates the immuno-inflammatory response (CRP, TNF-R75) after surgery.

Efficacy of parenteral nutrition supplemented with glutamine dipeptide to decrease hospital infections in critically ill surgical patients

BACKGROUND

Nosocomial infections are an important cause of morbidity and mortality in the surgical intensive care unit (SICU). Clinical benefits of glutamine-supplemented parenteral nutrition may occur in hospitalized surgical patients, but efficacy data in different surgical subgroups are lacking. The objective was to determine whether glutamine-supplemented parenteral nutrition differentially affects nosocomial infection rates in selected subgroups of SICU patients.

METHODS

This was a double-blind, randomized, controlled study of alanyl-glutamine dipeptide-supplemented parenteral nutrition in SICU patients requiring parenteral nutrition and SICU care after surgery for pancreatic necrosis, cardiac, vascular, or colonic surgery. Subjects (n = 59) received isocaloric/isonitrogenous parenteral nutrition, providing 1.5 g/kg/d standard glutamine-free amino acids (STD-PN) or 1.0 g/kg/d standard amino acids + 0.5 g/kg/d glutamine dipeptide (GLN-PN). Enteral feedings were advanced as tolerated. Nosocomial infections were determined until hospital discharge.

RESULTS

Baseline clinical/metabolic data were similar between groups. Plasma glutamine concentrations were low in all groups and were increased by GLN-PN. GLN-PN did not alter infection rates after pancreatic necrosis surgery (17 STD-PN and 15 GLN-PN patients). In nonpancreatic surgery patients (12 STD-PN and 15 GLN-PN), GLN-PN was associated with significantly decreased total nosocomial infections (STD-PN 36 vs GLN-PN 13, P < .030), bloodstream infections (7 vs 0, P < .01), pneumonias (16 vs 6, P < .05), and infections attributed to Staphylococcus aureus (P < .01), fungi, and enteric Gram-negative bacteria (each P < .05).

CONCLUSIONS

Glutamine dipeptide-supplemented parenteral nutrition did not alter infection rates following pancreatic necrosis surgery but significantly decreased infections in SICU patients after cardiac, vascular, and colonic surgery.

Adoptive transfer of TRAIL-expressing natural killer cells prevents recurrence of hepatocellular carcinoma after partial hepatectomy

BACKGROUND

Antitumor activity of the liver natural killer (NK) cells reportedly decreases after partial hepatectomy, suggesting that patients with such depressed immune status are susceptible to the recurrence of hepatocellular carcinoma (HCC). We hypothesize that adoptive immunotherapy using activated NK cells can be a novel strategy to improve the depressed immune status in patients with HCC after hepatectomy or partial liver transplantation. In the present study, we have tested this hypothesis by using a mouse model.

METHODS

Intraportal injection of 1-5 x 10(6) Hepa1-6 cells (hepatoma cell line) did not result in liver metastases in untreated B6 mice, but led to the growth of liver metastases after extensive partial hepatectomy. Utilizing this murine HCC metastasis model, we investigated the antitumor activity of both remnant liver and exogenously transferred NK cells.

RESULTS

The anti-HCC activity of liver NK cells significantly decreased after partial hepatectomy. The expression of CD69 and tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) on liver NK cells was temporarily downregulated. The adoptive transfer of NK cells, including a TRAIL-expressing fraction, extracted from the liver perfusates of poly I:C-stimulated B6 mice inhibited the growth of liver metastasis in B6 or (B6xBALB/c) F1 (B6CF1) mice that underwent hepatectomy and received intraportal Hepa1-6 injection.

CONCLUSIONS

These findings indicate that adoptive immunotherapy using activated NK cells extracted from normal liver perfusates may be a novel technique for reconstituting the depressed immune status in cases of living donor liver transplantation involving HCC patients, recipients of a partial liver graft.

Higher Levels of Serum Cytokines and Myocardial Tissue Markers During On-Pump Versus Off-Pump Coronary Artery Bypass Surgery

Increased Troponin I levels and pro-inflammatory cytokines have been reported in most patients undergoing cardiac surgery, ascribed to the type and extent of surgery, reperfusion injury, and the method of myocardial protection. We investigated their levels in patients undergoing on-pump (CCAB) or off-pump (OPCAB) coronary artery bypass surgery and whether these correlated with the extent of myocardial injury. One hundred twenty patients were prospectively randomized to undergo OPCAB (n = 60) or CCAB (n = 60). Hemodynamic and respiratory data, as well as serum CK-MB mass fraction, Troponin I, and interleukin (IL)-6, IL-8, and IL-10 levels, were collected perioperatively. Demographic, hemodynamic, and respiratory parameters were similar between the two groups. Troponin I was significantly lower in the OPCAB than in the CCAB group, either at the end of ischemia, end of surgery, 6-hour and 24-hour postoperatively (4 +/- 3, 5 +/- 3, 7 +/- 5, and 8 +/- 3 microg/L, vs. 19 +/- 18, 27 +/- 19, 28 +/- 13.5, and 33 +/- 8.5 microg/L, respectively, p < 0.05). Serum cytokine levels in the OPCAB patients were lower compared to the CCAB group at the end of surgery (32 +/- 35, 25 +/- 30, and 40 +/- 30 pg/ml for IL-6, IL-8, and IL-10 vs. 230 +/- 30, 140 +/- 70, and 125 +/- 50 pg/ml, respectively, p < 0.05). Plasma IL-6 levels correlated with the Troponin I levels at the end of surgery in both groups (r = 0.45, p = 0.01). Thus, OPCAB surgery is associated with reduced levels of Troponin I and activation of cytokines, compared to those in the CCAB group. High levels of these factors could correlate with myocardial damage during coronary artery bypass surgery. This finding warrants further laboratory and clinical confirmation in the future.

The effect of tramadol on serum cytokine response in patients undergoing pulmonary lobectomy

STUDY OBJECTIVE

To investigate the effect of tramadol on the production of serum interleukin (IL) 6, IL-10, and IL-2 and soluble (s) IL-2 receptor (R), thereby evaluating its effects on the proinflammatory and anti-inflammatory responses and immune function in cancer patients undergoing conventional pulmonary lobectomy.

DESIGN

Randomized, double-blinded, placebo-controlled study.

SETTING

University hospital.

PATIENTS

Forty ASA physical status I and II adult patients scheduled for conventional pulmonary lobectomy.

INTERVENTIONS

Patients were randomly divided into 2 groups (n = 20 in each group). Both groups received general anesthesia with enflurane combined with epidural blockade. At 5 minutes before skin incision, patients were given either tramadol 1.5 mg/kg intravenously (IV), followed by a continuous infusion of 0.5 mg/kg per hour until the end of surgery (group I), or IV normal saline (group II).

MEASUREMENTS AND MAIN RESULTS

Venous blood samples for the measurement of serum cytokine concentrations were taken before anesthesia and at set intervals until 24 hours after operation. Serum levels of IL-6 and IL-10 in both groups were increased significantly during and after operation compared with baseline levels (P < .05). No statistical differences between groups in terms of IL-6 and IL-10 were observed. Levels of IL-2 were elevated significantly at 4 hours after operation in group I as compared with baseline levels (P < .001), whereas they remained low at 4 and 24 hours after operation in group II (P < .01). There were significant increases in levels of sIL-2R at 4 and 24 hours after operation in group II as compared with baseline levels (P < .05) and at 24 hours after operation in group I (P < .01). Levels of IL-2 were higher at 4 and 24 hours after operation in group I than in group II (P < .01). Levels of sIL-2R were lower at 4 hours after operation in group I than in group II (P < .01).

CONCLUSIONS

IV infusion of tramadol does not seem to alter IL-6/IL-10 cytokine response to pulmonary lobectomy. As tramadol was associated with increased IL-2 and delayed enhancement of sIL-2R in our study, it may attenuate to some extent an impaired immune response in pulmonary lobectomy.

Impact of graft length on surgical damage after intestinal transplantation in rats

BACKGROUND

Intestinal grafts greatly affect nutrition and immunology in the host. The growth of the recipient and incidence of graft-versus-host disease depend on graft length. A larger graft may affect the host immune system, but little is known about how the length of the intestinal graft severely affects surgical intervention. We developed a cervical small bowel transplantation (SBT) rat model that minimized technical variations using a cuff method and studied the effects of graft length on surgical damage in SBT.

MATERIALS AND METHODS

We transplanted a whole (70 cm) or partial (15 cm) intestine into a syngeneic rat combination of LEW (MHC haplotype: RT1(l)) to LEW and evaluated changes in perioperative hemodynamics and the endogenous endotoxin level. Natural killer (NK) cell activity in the peripheral blood and the immunologic response of the recipient spleen were also studied.

RESULTS

In the whole SBT model, body weight loss was more severe than in the segmental SBT model; the rats in the former model often died, while all in the latter survived indefinitely. The systemic blood pressure markedly decreased in the whole SBT group immediately after reperfusion. The proliferative activity of splenic lymphocytes stimulated by concanavalin A was also more severely inhibited in the former model than in the latter postoperatively. NK cell activity in the whole SBT rats declined more severely than the segmental SBT rats 3 days postoperatively.

CONCLUSION

The longer graft severely induced surgical intervention; and influenced host immunosuppression, resulting in the higher mortality in rats undergoing whole SBT.

Randomized trial of surgical staging (extraperitoneal or laparoscopic) versus clinical staging in locally advanced cervical cancer

OBJECTIVE

To define the role of pretreatment surgical staging for locally advanced cervical carcinoma.

METHODS

A two-step randomized trial was conducted to compare clinical staging (arm A) versus surgical staging (arm B) and to compare the laparoscopic (LAP) with the extraperitoneal (EXP) approach in previously untreated locally advanced cervical carcinoma. After the first randomization, those in arm B were randomly allocated to either LAP or EXP. An interim analysis was planned to evaluate the feasibility of LAP versus EXP, which led to the current report.

RESULTS

A total of 61 patients were eligible (arm A, 29; arm B, 32). The operation time, blood loss, and lymph node yield of LAP and EXP were not significantly different. Serious acute and late toxicity was not different between arm A and arm B, or LAP versus EXP. Para-aortic node metastasis was documented in 25% (95% confidence interval, 10% to 40%) of patients on arm B. An interim analysis was performed in January 2000. Patients on arm B had significantly worse progression-free survival than those on arm A. Hazard ratios of relapse/persistent or death were 3.13 (P = 0.005) and 1.76 (P = 0.150), respectively. Patient accrual was terminated according to the early stopping rules. With further follow-up till December 2001, the difference in progression-free survival remained significant (P = 0.003), and the difference in overall survival became significant (P = 0.024) as the data matured.

CONCLUSION

The benefit of pretreatment surgical staging for cervical carcinoma remained unproven. The detrimental effects of surgical staging observed in this study must be considered in the design of clinical guidelines or future trials.

Long-term monitoring of cell-mediated immunity in disease-free breast cancer patients: a preliminary retrospective study

In 102 N- and 44 N+ disease-free breast cancer patients, lymphocytic populations and skin reaction of delayed hypersensitivity (SRDH) were monitored up to 266 months after mastectomy to find out whether they were similar or different from control values. In two selected groups of 34 N- and 11 N+ breast cancer patients, the whole 10 year follow-up was divided into three subintervals, each of them lasting 40 months and the time course of lymphocytic populations was evaluated. In the 102 N- patients, mean CD4+, CD8+, CD3+ values were lower (P < 0.01, P < 0.001, P < 0.01, respectively) while CD4+/CD8+ ratio was higher (P < 0.05) than in controls. Fifteen N- breast cancer patients (16%) were anergic compared to 30(32%) of controls (P < 0.05). In the 34 selected N- breast cancer patients soon after mastectomy the mean value of CD4+, CD8+, CD3+ T subpopulations was lower (P < 0.01, P < 0.001, P < 0.01, respectively) than in controls. Successively their mean value increased so that in the last subinterval they were not or were only slightly lower (P n.s., P < 0.05, P < 0.05, respectively) than in controls. In the 44 N+ patients, mean CD4+, CD8+, CD3+ values were lower (P < 0.001, v < 0.05, P < 0.01, respectively) and CD19+ lymphocytes higher (P < 0.001) than in controls. Five N+ breast cancer patients (13%) were anergic compared to 32% of controls (P < 0.05). In the 11 selected N+ breast cancer patients soon after mastectomy, the mean value of CD4+, CD8+ T subpopulations and CD16+56+ cells was significantly lower (P < 0.001, P < 0.001, P < 0.01, respectively) than in controls. Successively their mean value constantly increased so that in the last subinterval, no or slight (P n.s., P < 0.05, P n.s., respectively) significant difference compared to controls occurred. The mean CD4+/CD8+ ratio value of N- patients was significantly higher than in controls. However in the last subinterval, the significance was lower than in the first one (P < 0.05 and P < 0.01, respectively). In the N+ patients, the mean value of CD4+/CD8+ ratio was constant, although not significantly, lower than in controls; however it progressively increased from the first to the last subinterval. Therefore the significance of the difference of the mean CD4+/CD8+ ratio between N- and N+ patients strongly decreased from the first to the last subinterval (P < 0.001 and P < 0.05, respectively). These data indicate that in breast cancer patients, following mastectomy, a significant activation of memory and CD4+ T cells and long-term decrease of the circulating immunocompetent CD4+, CD8+ and CD16+56+ cells occurs. The prolonged disease-free interval observed in the 34 N- and 11 N+ breast cancer patients can be correlated with the restoration of the normal state of cell-mediated immunity.

Effects of arginine-enriched total parenteral nutrition on inflammatory-related mediator and T-cell population in septic rats

OBJECTIVES

Previous reports have shown that oral arginine (Arg) has immune-enhancing properties in injury. However, the effects of parenterally infused Arg on sepsis are not well understood. We used a septic rat model to study Arg infusion in inflammatory-related cytokines and blood T lymphocyte population in vivo.

METHODS

Rats with internal jugular catheters were assigned to one of two groups. Both groups received isonitrogenous total parenteral nutrition (TPN) supplemented with 270 mg of nitrogen per kilogram per day as Arg or glycine (Gly). TPN provided 270 kcal/kg of body weight, and the kilocalorie:nitrogen ratio was 143:1. TPN was maintained for 5 d plus 2, 4, or 6 h or 6 d, according to the scheduled deaths of the rats. On day 5, sepsis was induced by cecal ligation and puncture (CLP). After CLP for 2, 4, 6, and 24 h, rats were killed.

RESULTS

The results showed that interleukin-1beta and tumor necrosis factor-alpha concentrations in peritoneal lavage fluid at 6 h and interleukin-6 levels at 24 h after CLP in the Gly group were significantly higher than those in the Arg group. The T-lymphocyte population in blood showed that CD8(+) suppressor T-cell number was significantly higher in the Gly group than in the Arg group at 6 h after CLP. The blood CD4(+):CD8(+) ratio was significantly higher in the Arg group than in the Gly group at 24 h after CLP. A negative nitrogen balance was observed in the Arg and Gly groups after CLP; there was no significant difference in nitrogen balance between the septic groups. No difference in survival rate at 24 h after CLP was observed between the groups.

CONCLUSIONS

The results showed that, compared with the Gly group, TPN preinfused with Arg reduces the production of inflammatory mediators at the site of injury and that cellular immunity is enhanced at 24 h after CLP. Parenterally administered Arg had no beneficial effect in preventing nitrogen loss and improving survival in septic rats. Whether Gly has specific effects that reduce the effects of Arg require further investigation.

The effect of glutamine-supplemented total parenteral nutrition on nitrogen economy depends on severity of diseases in surgical patients

BACKGROUND

Gln is an important substrate for enterocyte and rapid proliferation cells. Studies have shown that parenteral supplementation of Gln maintains the intracellular Gln pool, improves nitrogen balance and shortens hospital stay. However, some studies showed Gln-supplemented TPN had no effect on restoring the Gln pool in critically ill patients.

OBJECTIVE

To evaluate the effect of glutamine (Gln) dipeptide supplementation of total parenteral nutrition (TPN) on postoperative nitrogen balance and immune response of patients undergoing surgery.

METHODS

This study is a prospective, randomized double-blind clinical trial. APACHE II score and TISS were used to evaluate the patients after admission. Forty-eight patients with major abdominal surgery were allocated to two groups to receive isonitrogenous (0.228 g nitrogen/kg/day) and isoenergetic (30 kcal/kg/day) TPN for 6 days. Two groups (Conv and Ala-Gln) were further divided to high (APACHE>or=6) and low (APACHE <6) groups. Control group (Conv) received 1.5 g amino acids/kg/day, whereas the Ala-Gln group received 0.972 g amino acids/kg/day and 0.417 g of L-alanyl-L-glutamine (Ala-Gln)/kg/day. Blood samples were collected on day 1 and day 6 after surgery for plasma amino acid and CD4, CD8 cell and T lymphocyte analysis. Cumulative nitrogen balance were also measured on day 2, 3, 4, 5 postoperatively.

RESULTS

Although there was a tendency to have better cumulative nitrogen balance on the postoperative days in the Ala-Gln group, no significant difference was observed between two groups. However, a better significant cumulative nitrogen balance was observed on the 2nd, 3rd and 5th postoperative day in the Ala-Gln group than in the Conv group in patients with APACHE II <6, whereas no significant difference was noted in patients with APACHE II >or= 6. No difference in urine 3-methylhistidine excretion were observed between the 2 groups. Patients in the Ala-Gln group had significant higher T lymphocyte and CD4 cells than did those in the Conv group.

CONCLUSION

TPN supplemented with Gln dipeptide had beneficial effect on enhancing the immune response. However, the effect of Ala-Gln administration on improving nitrogen economy was only observed in patients with low APACHE II scores. These results may indicate that Gln required for reversing the catabolic condition may depend on the characteristics and severity of the diseases.

Effects of glutamine-supplemented total parenteral nutrition on cytokine production and T cell population in septic rats

BACKGROUND

This study was designed to investigate the effects of total parenteral nutrition (TPN) enriched with glutamine (GLN) on in vivo cytokine production and cellular immune response in early and late septic stages of rats.

METHODS

Male Wistar rats were divided into 2 experimental groups and received TPN solution at an energy level of 270 kcal/kg body weight. The TPN solutions were isonitrogenous and identical in nutrients composition except for differences in amino acid content. One group received 2% GLN, whereas the other group received glycine (Gly) instead. TPN was maintained for 5 or 6 days according to the sacrifice schedule of the rats. On day 5, sepsis was induced by cecal ligation and puncture (CLP). Respective groups of rats were sacrificed 2, 4, 6, and 24 hours after CLP.

RESULTS

Sepsis resulted in a negative nitrogen balance in both groups, and nitrogen loss was significantly lower in the GLN than the Gly group. Interleukin (IL)-2 and interferon (IFN)-gamma in most of the samples collected at various time points were not detectable in plasma or peritoneal lavage fluid. No differences in plasma IL-6 and TNF-alpha concentrations were observed between the GLN and Gly groups. Also, there were no significant differences in IL-1beta, IL-6, and TNF-alpha concentrations in peritoneal lavage fluid between the 2 groups at various time points. The CD4+/CD8+ ratio was significantly higher in the GLN group than in the Gly group only at 4 hours after CLP, and no difference was observed at 24 hours after CLP.

CONCLUSIONS

TPN preinfused with a GLN-supplemented solution had a beneficial effect in ameliorating the extent of negative nitrogen balance in septic rats. However, parenterally administered GLN did not reduce the production of inflammatory mediators systemically or at the site of injury, and the influence on enhancing cellular immunity was not obvious.

Naltrexone administration attenuates surgery-induced immune alterations in rats

Surgery is a commonly performed procedure which produces substantial alterations in immune function in both humans and animals. To better understand the mechanism of surgery-induced immunomodulation, the present study investigated the effect of the opioid antagonist naltrexone on surgery-induced immune alterations in rats. Based on previous investigations in our laboratory, rats underwent a 6-cm laparotomy with no internal manipulation and immunological assessments were completed 24 h following the surgical procedure. Naltrexone was administered at the time of surgery and every 4 h thereafter until immune assessment. Results showed that naltrexone attenuated the surgery-induced decrease in natural killer cell cytotoxicity, B-cell proliferation, T-cell proliferation, and production of the cytokine IFN-gamma. These results are among the first to show that pharmacological antagonism of opioid receptors can prevent deleterious immune changes in the postoperative state, suggesting a detrimental role of the endogenous opioids in surgical procedures.

Spontaneous regression of a germinoma in the pineal body after placement of a ventriculoperitoneal shunt

The authors report a case in which a germinoma in the pineal body displayed spontaneous regression after placement of a ventriculoperitoneal (VP) shunt. Spontaneous regression of malignant tumors is extremely rare, occurring in only one of 60,000 to 100,000 patients. Although in rare cases spontaneous regression is known to occur in patients with testicular seminomas, only one case of spontaneous regression of a primary pineal germinoma has so far been reported. In the present case a 17-year-old man presented with headache. A tumor in the pineal body and acute hydrocephalus were revealed by head computerized tomography (CT) and magnetic resonance (MR) imaging, and VP shunt placement was performed. Computerized tomography scanning of the head was performed four times during a 2-week period following the operation, and the patient was temporarily discharged to return to school. At the time of discharge, CT scanning demonstrated no change in the size of the tumor. Two months later, the patient was readmitted to the hospital to undergo surgery. At that time, head MR imaging revealed regression of the tumor. The pathological diagnosis of the lesion was germinoma. The patient underwent three courses of chemotherapy, during which carboplatin and etoposide were administered, in addition to a 24-Gy dose of radiotherapy. No manifestations of nerve impairment were noticed, and the patient was observed on an outpatient basis. The authors think that the factors involved in tumor regression included the effects of the VP shunt, the effects of radiation absorbed during head CT scanning, and the role of the patient's own immune response. However, no conclusion has been reached concerning the actual cause.

Influence of multimodality therapy on the cellular immunity of patients with esophageal cancer

BACKGROUND

Cancer patients have often been reported to have impaired immune function, and the effect of treatment modalities, such as surgery, irradiation, and chemotherapy, in depressing patients' immunity has also been reported. In this investigation, the effect of treatment on the cellular immunity of esophageal cancer patients was evaluated.

METHODS

Immunological parameters, such as natural killer (NK) activity and lymphocyte subsets in peripheral blood, were measured in 32 esophageal cancer patients on 5 occasions (on the day of admission, 2 days before surgery, and 1 week, 1 month, and 2 months after surgery).

RESULTS

NK activity was greatly impaired shortly after the operation, and the percentages of lymphocytes as a whole, and CD8+, CD16+, and CD57+ lymphocytes were significantly decreased, on the other hand, a postoperative increase in the CD4+/CD8+ ratio was observed. No significant depression of immune function by postoperative irradiation was observed.

CONCLUSIONS

The results of this study suggest that cellular immunity, especially cytotoxicity, shortly after esophagectomy may be greatly impaired by the surgical stress of esophagectomy and an added effect of chemotherapy.

Usefulness of autologous blood transfusion for avoiding allogenic transfusion and infectious complications after esophageal cancer resection

BACKGROUND

A retrospective investigation was conducted to determine whether autologous blood collection could reduce allogenic transfusion after resection of esophageal cancer and whether allogenic transfusion influenced postoperative infection.

METHODS

Patients (n = 100) who met the criteria for hemoglobin, age, body weight, and serum protein donated 800 mL of autologous blood from May 1994 to December 1997. The control group (n = 248) was selected from patients who met the same criteria and did not donate autologous blood over the 10 years before the start of autologous blood collection.

RESULTS

Only three patients (3%) from the autologous group required allogenic transfusion versus 84 patients (33.7%) from the control group. Sixteen of the 26 patients who received more than 4 units of allogenic blood contracted postoperative infections compared with 25 of 165 patients who did not (P < .0001). Autologous blood transfusion significantly increased the probability of avoiding allogenic transfusion (odds ratio, 27.58), and allogenic transfusion was significantly related to postoperative infection (odds ratio, 1.19), according to logistic regression analysis.

CONCLUSIONS

Autologous blood collection reduces the need for allogenic transfusion in patients undergoing resection of esophageal cancer, and avoidance of allogenic transfusion may reduce the risk of postoperative infection.

Recovery from lymphocytopenia following extracorporeal circulation: simple indicator to assess surgical stress

This study investigated whether the lymphocyte count is a useful indicator to assess surgical damage following extracorporeal bypass. In Study 1, to investigate the correlation between extracorporeal circulating time (ECCT) and lymphocyte counts, 40 elective CABG patients were studied retrospectively. The lymphocyte recovery ratio (LRR), which represented the actual lymphocyte count divided by the preoperative lymphocyte count, was determined preoperatively, and on postoperative day (POD) 1, POD 3, and POD 5. In Study 2, the correlation between the interleukin-8 (IL-8) level and LRR was examined prospectively in elective CABG patients (n = 20). We measured the LRR and serum IL-8 levels preoperatively and during extracorporeal circulation (ECC) at 5 min, at the end of ECC, and 1, 3, and 12 h following ECC termination. Study 1 showed that the LRR decreased until POD 1 and gradually increased thereafter. The LRR had a negative correlation with the ECCT. In Study 2, the IL-8 level demonstrated a time course opposite to that of the LRR; it increased until 3 h after ECC termination and declined thereafter. There was a significant negative correlation between the LRR on POD 3 and the IL-8 level at 3 h after ECC termination. In summary, long-term ECC induced significant and prolonged lymphocytopenia. The LRR had a negative correlation with IL-8. These results indicated that the LRR may represent the degree of surgical stress following ECC; therefore, the counting of lymphocytes can be a quite useful bedside monitor to assess surgical damage and prognosis.

Downregulation of T helper type 1 immune response and altered pro-inflammatory and anti-inflammatory T cell cytokine balance following conventional but not laparoscopic surgery

BACKGROUND

The clinical advantages of laparoscopic procedures result from a minimized surgical trauma. The present study was performed to investigate immunosupression following laparoscopic operations as compared with open surgery. Our analysis focused on the T cell secretion of cytokines that regulate the critical balance of either T helper type-1 (Th1)- and Th2-mediated immune responses on pro- and antiinflammatory activities.

METHODS

In a prospective study, immunological data of 26 patients submitted to laparoscopic cholecystectomy (LCE) and 17 patients undergoing conventional cholecystectomy (CCE) for symptomatic cholecystolithiasis were compared. Patients with acute cholecystitis and patients developing postoperative complications or receiving immunosuppressive medication were excluded. Production of interferon (IFN)-gamma, interleukin (IL)-2, IL-4, tumor necrosis factor (TNF)-alpha, and IL-10 by isolated T cells stimulated by cross-linking of CD3 and CD28 was evaluated preoperatively as well as on postoperative days 1 and 6 or 7. Cytokines were measured by immunoenzymometric assay.

RESULTS

IFN-gamma, TNF-alpha, and IL-2 production by T cells decreased significantly by 48.3%, 36.6%, and 36.8%, respectively, on postoperative day 1 after CCE, but not after LCE. These results indicate severe suppression of Th1-type and proinflammatory cytokines after the open operation. In contrast, IL-4 and IL-10 did not show significant changes in either group suggesting that Th2 cell response and anti-inflammatory activity remained normal.

CONCLUSIONS

The present study shows that open, but not laparoscopic cholecystectomy is associated with a marked suppression of T lymphocytes functions as indicated by deregulation of both the Th1/Th2 and the pro-/anti-inflammatory cytokine balance. The results therefore suggest that downregulation of Th1 cell-mediated immune response and pro-inflammatory activity of T cells is a hallmark of open, but not laparoscopic surgery.

Severity, time, and beta-adrenergic receptor involvement in surgery-induced immune alterations

Although investigations of surgical stress in animals have reported immune alterations, surprisingly little is known about the variables or mechanisms contributing to the effect. Thus, we completed a series of experiments investigating the immune-altering effects of surgery severity, time of maximal immune alterations, and recovery, as well as the involvement of beta-adrenergic receptors in surgery-induced immune alterations in Lewis rats. Immune alterations included natural killer (NK) cell cytotoxicity as well as B- and T-cell proliferation. Results showed increased immune suppression with larger incisions (6 cm > 3 cm > anesthesia > saline). In addition, maximal immune alterations induced by surgery occurred after 24 h; anesthesia effects predominated at the earlier time points. Recovery of immune status varied depending on the immunological measure of interest. Although NK cell cytotoxicity returned to control values within 2 days, B-cell proliferation remained suppressed for at least 8 days, and T-cell proliferation did not begin to recover until 4-8 days following the surgical procedure. To assess the mechanisms involved in surgery-induced immune alterations, follow-up assessments evaluated the effect of nadolol, a beta-adrenergic receptor antagonist, on surgery-induced immune alterations. Results show that nadolol blocks the surgery-induced reduction in B- and T-cell proliferation but has no effect on the suppression of NK cell cytotoxicity. These results indicate the need to consider surgical severity and postoperative time of immune assessment when investigating the immune-altering effects of surgery. Importantly, activation of beta-adrenergic receptors appears to play a modulatory role in surgery-induced immune alterations.

The influence of surgical stress on T cells: enhancement of early phase lymphocyte activation

For the control of postoperative infection, it may be important to understand the possible influences of surgical stress on the host immune system. To this end, we examined how the early phase of lymphocyte activation was affected in patients after major surgery (eight patients with esophageal carcinoma and six undergoing cardiac surgery) using a flow cytometric assay based on expression of the early activation antigen, CD69. Freshly isolated T cell in preoperative and postoperative samples did not express CD69. When peripheral blood mononuclear cells were stimulated in vitro, the expression of CD69 was greatly enhanced in both CD4 and CD8 T cells, compared with the preoperative samples. The proportion of de novo CD69-expressing cells in the CD4 subset was approximately 3 times (Postoperative Day 1) and 4 times (Postoperative Days 2, 3, 5, and 7) greater than those preoperatively, whereas the proportion of de novo CD69-expressing cells in the CD8 subset was approximately 1.5 times (Postoperative Days 2 and 5) and 2 times (Postoperative Day 3) greater than those preoperatively. The proportion of CD69+ cells was significantly greater in the CD4+ subset than in the CD8+ subset during the postoperative period.

IMPLICATIONS

Our results show that major surgical stress enhances the early phase of lymphocyte activation. The augmentation of activation was greater in CD4 (helper) T cells than in CD8 (cytotoxic) T cells.

Increased surgery-induced metastasis and suppressed natural killer cell activity during proestrus/estrus in rats

We have previously reported sex- and estrous-related differences in host resistance to the metastatic development of a mammary adenocarcinoma cell line, MADB106, in the Fischer 344 (F344) rat. In other studies, we found that surgery suppressed natural killer (NK) cell activity and increased the NK-sensitive metastatic development of MADB106 tumor cells. The current study was designed to explore whether sex or estrous phase at the time of surgery impacts the degree of such deleterious effects of surgery. Such estrous effects could be related to an ongoing clinical debate regarding the importance of the timing of breast cancer surgery with the menstrual cycle in premenopausal women. Mature F344 males and cycling females underwent either experimental laparotomy with halothane anesthesia, halothane anesthesia alone, or were untreated. Five hours after surgery, animals either were injected with radiolabeled MADB106 tumor cells and assessed for lung tumor cell retention 12 hours later, or underwent blood withdrawal for in vitro assessment of NK cell activity. MADB106 tumor cells metastasize only to the lungs, and lung tumor cell retention is: a) an early indicator of the number of metastases that would develop weeks later, and b) highly sensitive to in vivo levels of NK activity. This mammary adenocarcinoma cell line is syngeneic to the inbred F344 strain of rats used in our studies, thus constituting a model for breast cancer metastasis. The results indicated that sex, estrous phase, and surgery interacted in their effects on NK cell activity and tumor metastasis. MADB106 lung tumor cell retention was increased by surgery in both sexes (2- to 3-fold) compared to the anesthesia only and control groups. This increase, however, was significantly greater in proestrus/estrus (P/E) females than in metestrus/diestrus (M/D) females. Among the control animals, females in P/E exhibited significantly less NK cytotoxic activity compared to the males, and the NK activity exhibited by females in M/D was between these two groups. Surgery suppressed NK cytotoxic activity to a similar level in all groups. Possible implications of these findings for the surgical care of women with breast cancer are discussed.

Spontaneous regression of primary intracranial germinoma. A case report

BACKGROUND

Testicular seminomas are well known to regress spontaneously at a higher incidence than other tumors. To date, there have been no reports of spontaneous regression of an intracranial germinoma, although these tumors are histologically identical to testicular seminomas.

METHODS

The authors present a patient with a primary intracranial germinoma that regressed spontaneously.

RESULTS

A 21-year-old man was admitted to the study facility with acute onset of headache and vomiting. He had a 3-year history of polydipsia and polyuria. Computed tomography (CT) demonstrated a large tumor in the third ventricle, accompanied by hydrocephalus. He underwent ventriculoperitoneal shunt placement on the second day of hospitalization. A CT scan obtained on the fifth postoperative day demonstrated a remarkable decrease in tumor size. Because serial magnetic resonance imaging (MRI) demonstrated a gradual decrease in tumor size, tumor resection was not performed at that time. The patient was discharged and followed with MRI. The tumor continued to regress for more than 2 months. The patient was readmitted due to tumor regrowth, confirmed by MRI 4 months after the initial admission, despite the absence of symptom exacerbation. Two weeks later, the suprasellar portion of the tumor was resected through a right frontotemporal craniotomy. The histopathologic diagnosis was a germinoma. No concurrent tumors were found on whole body examination. The residual tumor gradually regressed after conventional radiation therapy and there has been neither tumor recurrence nor metastasis to date.

CONCLUSIONS

Although the precise cause of the transient partial regression is unknown, this case indicates that, like their testicular counterparts, intracranial germinomas may on occasion spontaneously regress.

Surgical complications related to peri-operative adjuvant chemotherapy in breast cancer. Results of a prospective, controlled, randomized clinical trial

From May 1985 to June 1992, 375 patients were enrolled in a prospective controlled randomized clinical trial of peri-operative adjuvant chemotherapy (PAC) associated with long-term adjuvant chemo-endocrinotherapy in order to test the effectiveness of reducing the time interval between surgery and chemotherapy. The short-term surgical complications related to PAC are reported in order to verify whether such treatment might negatively affect the results of breast cancer surgery. One hundred and eighty-nine patients were randomly assigned to the peri-operative treatment, and 186 to the control group. Patients undergoing PAC received one course of cyclophosphamide (600 mg/sqm), epidoxorubicin (60 mg/ sqm), and 5-fluorouracil (600 mg/sqm) (CEF) within 48-72 h following surgery. Pathologically node-positive (N+) patients, who were given peri-operative CEF, had five further cycles of CEF alternated with six cycles of CMF (cyclophosphamide 600 mg/sqm, methotrexate 40 mg/sqm, and 5-fluorouracil 600 mg/sqm). All the other N+ patients received six cycles of CEF alternated with six cycles of CMF, starting within 30 days of surgery. No significant difference in post-operative morbidity was observed as regards median hospital stay (8 days), number of outpatient dressings (3.5 vs 3), seroma (51 (26.9%) vs 45 (24.2%)), lymphatic drainage (400 ml vs 409 ml), and post-operative infections, both local (10 vs 9) and in extraoperative foci (6 vs 7), in the study and control group, respectively. The toxicity of the peri-operative CEF was mainly gastrointestinal (nausea and vomiting, 55%; stomatitis, 3%), with only a small percentage (9%) reaching grades III-IV. Hair loss was the other main side effect (55%) with baldness in only 3%. Post-operative complications following radical breast cancer surgery seem to be primarily related to operative details (type of incision, accurate nerve-sparing technique, bleeding control, closure of subcutaneous and skin, drainage, aseptic technique) rather than to the one course of PAC.

The immune-suppressive nature of pain

OBJECTIVES

To review evidence that the immune system plays a role in controlling the spread of cancer and findings that perioperative pain relief improves immune status and health outcomes.

DATA SOURCES

Research studies and review articles pertaining to immunity, immune function, stress, and immune-suppressive nature of pain.

CONCLUSIONS

Pain not only results in suffering but is a pathogen itself, capable of facilitating the progression of metastatic disease. Adequate pain relief decreases these risks.

IMPLICATIONS FOR NURSING PRACTICE

Adequate pain relief is not only a primary concern in caring for individuals in pain but may be a matter of physiologic necessity as further studies reveal the immune-suppressive nature of pain.

Effect of surgical stress on immune function in patients with urologic cancer

BACKGROUND

To determine the immunosuppressive effect of surgery for urologic cancers, multiple variables of immune function were measured serially before and after operation in patients with urologic cancer.

METHODS

Peripheral blood was obtained before operation and at postoperative day 7 and 14 from 20 patients with bladder cancer, renal pelvic, or ureteral cancer, or renal cell carcinoma.

RESULTS

In patients with bladder cancer who were undergoing radical cystectomy with use of intestine for urinary diversion, the serum level of immunosuppressive acidic protein (IAP) increased, and serum levels of immunoglobulin (Ig)A, IgG, and IgM decreased after operation. In contrast, the number of CD25+ lymphocytes significantly increased. Transurethral resection of bladder cancer also resulted in an increase in serum IAP level, however, the number of CD4+ and human leukocyte-associated HLA-DR+ lymphocytes increased. In patients with renal pelvic or ureteral cancer undergoing nephroureterectomy with cuff, the level of serum IAP increased and serum IgG level decreased after operation. By contrast, the number of CD3+ lymphocytes increased. In patients with renal cell carcinoma, radical nephrectomy led to a significant increase in the number of CD8+ lymphocytes.

CONCLUSIONS

These findings suggest that surgical stress in patients with urologic cancer may result in both suppression and stimulation of host immunity.

Hyperstimulation of leukocytes by plasma from cardiopulmonary bypass patients is diminished by alpha-MSH pretreatment

Cardiopulmonary bypass (CPB) results in a diffuse inflammatory response characterized in part by hyperstimulation of leukocytes. We have previously shown that this hyperstimulation appears to be due, in part, to an increase in the release of biological response modifiers (BRMs) such as cytokines. In the present study, we evaluated the ability of a naturally occurring immunocyte inhibitory substance, alpha-melanocyte-stimulating hormone (alpha-MSH), to prevent the hyperstimulation caused by CPB. Monocytes and granulocytes were pretreated with alpha-MSH (10(-6) M) before exposing the cells to plasma obtained from patients who had undergone CPB, as CPB plasma would stimulate native monocytes and granulocytes in a manner similar to that observed in CPB patients. Pretreatment of these cells with alpha-MSH significantly diminished the hyperstimulation induced by CPB plasma in a concentration-dependent manner. In contrast, when the cells were first or simultaneously exposed to CPB plasma and then to alpha-MSH, alpha-MSH had no effect. Furthermore, use of the specific neutral endopeptidase inhibitor, phosphoramidon, significantly increased the efficacy of alpha-MSH in inhibiting CPB-induced immunocyte activation. The data demonstrate that pretreatment of monocyte/macrophages and granulocytes with alpha-MSH effectively inhibits the immune hyperstimulation induced by CPB-plasma exposure. In addition, the data strongly suggest that preexposure to other naturally occurring immune inhibitory substances may diminish the hyperstimulation associated with CPB. The study also further confirms that this hyperstimulation may, in part, be due to BRMs released from immunocytes.

A pilot study of adjuvant hepatic arterial infusion chemotherapy, associating 5-fluorouracil and leucovorin, after resection of colorectal cancer liver metastases

We initiated a pilot study of adjuvant hepatic arterial infusion chemotherapy (AHAIC) using 5-fluorouracil (5-FU) and leucovorin. Hepatic arterial infusion ports were placed in 15 consecutive patients undergoing curative resection of colorectal liver metastases. The chemotherapy regimen consisted of a weekly infusion of 5-FU (12 mg m 2 per day) and leucovorin (200 mg m 2 per day) for 12 months. The mean follow-up was 22 months (range 3-62 months, SD 21-37 months). There were no clinical or biological complications related to chemotherapy, except for sharp epigastric burns in four patients immediately after 5-FU infusions. Catheter irreversible occlusions led to early cessation of the treatment in three patients. Four of the 15 evaluable patients developed recurrent disease. The site of relapse was the liver in two patients and extra-hepatic sites in the two remaining patients. Three of these four patients died of their recurrent disease. These results suggest that 5-FU and leucovorin can be combined for AHAIC in a long duration regimen with a very low rate of side-effects. This protocol could be safely employed in a prospective randomized study in combination with 5-FU systemic infusions.

Inflammatory responses in open versus laparoscopic herniorrhaphy

The aim of this study is to verify whether differences could be found or not as concerns of the postoperative surgical stress between the conventional open herniorrhaphy and laparoscopic herniorrhaphy. We therefore compared the immunological and inflammatory responses to open and laparoscopic procedures in this study. The sex, age, weight, and height characteristics of group 1 (open surgery group) matched those of group 2 (laparoscopic surgery group), and no statistically significant differences were found between them. Nor were there any statistically significant differences in operating time or the postoperative hospitalization. Blood samples were collected preoperatively [postoperative day (POD)0], POD 1 and 5, and the following parameters were assessed: total leukocyte (WBC) count, including neutrophil and lymphocyte subpopulations, HLA-DR+CD3+, IL-6, C-reactive protein (CRP), serum albumin, and body temperature. No differences were detected between two groups in leukocyte, neutrophil, or lymphocyte count, HLA-DR+CD3+, IL-6, albumin, or body temperature or any of the postoperative days. The only statistically significant difference was a higher CRP value in the laparoscopy group than the open group only on POD 1 (p < 0.05). It can be concluded that the laparoscopic approach appears to offer no advantages over the open approach to herniorrhaphy from the standpoint of immunological and inflammatory responses.

Pretreatment with enteral cholestyramine prevents suppression of the cellular immune system after partial hepatectomy

OBJECTIVE

The authors tested the hypothesis that the beneficial effects of the endotoxin-binding agent cholestyramine on the postoperative course in rats that had undergone a partial hepatectomy was the result of improvement of cellular immune functions.

SUMMARY BACKGROUND DATA

Major liver resection is associated with severe postoperative complications and a high incidence of systemic infections. Gut-derived endotoxins previously were shown to be involved in the pathogenic processes after partial hepatectomy in rats. In addition, enteral cholestyramine improved postoperative survival, but how its beneficial effects are mediated is not clear.

METHODS

Rats that were force-fed for 7 days with either cholestyramine (150 mg/day) or 0.9% saline (equal volume) were randomized to undergo a partial hepatectomy or a sham operation. After 24 hours, the rats were killed and splenic mononuclear cells were tested in vitro for mitogenic responses and cytokine production.

RESULTS

Proliferative responses of splenic B and T lymphocytes and lipopolysaccharide-stimulated production of tumor necrosis factor and interleukin-1 by splenocytes were lower in rats after partial hepatectomy than in sham-operated animals. An increased concanavalin A-stimulated production of interleukin-2 also was found after partial hepatectomy compared with sham levels. Pretreatment with enteral cholestyramine preserved cellular proliferative responsiveness of both B and T cells, and restored cytokine production by splenocytes to sham levels.

CONCLUSION

Prophylactic treatment with enteral cholestyramine preserved cellular immune functions after partial hepatectomy in the rat, which may explain its beneficial effects on the postoperative course. Furthermore, the authors' results are consistent with the hypothesis that endotoxemia is involved in the pathogenesis of the cellular immune derangements after partial hepatectomy.

Metabolic responses to cholecystectomy: open vs. laparoscopic approach

Laparoscopic cholecystectomy is considered a minor surgical procedure. In a prospective, randomized study, we compared the metabolic responses to surgery in two groups of patients submitted to open or laparoscopic cholecystectomy. The aim of the study was to verify if the latter caused less metabolic changes. Blood samples were drawn before the operation (basal), 1 h and 2 h after skin incision, and on the first and second postoperative days. The following parameters were studied: cortisol, renin, and leukocytes, including subpopulations. The mean values for age, weight, height, basal neutrophil and lymphocyte counts, basal values of cortisol and renin of patients, and sex distribution of group 1 patients (open, n = 20) matched with those for group 2 (laparoscopic, n = 20), with the exception of age (p < 0.05). No differences were detected between the two groups in terms of cortisol and renin values. However, the neutrophil count 1 h after skin incision was statistically significantly higher with the laparoscopic approach (p < 0.05). The lymphocyte count on the second postoperative day was also statistically significantly higher in group 2 (p < 0.05). We conclude that when a cholecystectomy is performed, the laparoscopic approach has no advantage over the open approach from the standpoint of the metabolic responses we studied. It appears that leukocytes have a more rapid return to normal values after laparoscopic cholecystectomy. Although pneumoperitoneum is known to be responsible for important cardiorespiratory changes, no worse response was found in the laparoscopic group than in the open group.