Immunological consequences of laparoscopic surgery, speculations on the cause and clinical implications

BACKGROUND

Immune suppression is an established consequence of surgical stress and trauma. Postoperative changes in the systemic immune system are proportional to the degree of surgical trauma and subsequent immune suppression may be implicated in the development of infectious complications and tumor metastasis formation. Laparoscopic surgery reduces the magnitude of the operative trauma and is thought to preserve postoperative immunological defenses.

METHODS

Relevant literature concerning postoperative immune functions and laparoscopic surgery was reviewed and clinical implications are discussed.

RESULTS

The influence of laparoscopic surgery on the postoperative systemic immune response is significantly less after laparoscopic cholecystectomy than with the conventional approach. Few immunological data are available concerning more advanced laparoscopic procedures. Various animal model studies of postoperative septic complications and tumor growth show that the postoperative preservation of the systemic immune response after laparoscopic surgery can have enormous clinical advantages.

CONCLUSION

Laparoscopic surgery preserves the postoperative immunological defenses. In the future, this may imply a lower number of infections, less local recurrence and even fewer distant metastases. Prospective randomized studies are necessary to see whether these suspected advantages can be demonstrated in clinical practice.

Reduced postoperative infections with an immune-enhancing nutritional supplement

OBJECTIVES/HYPOTHESIS

Malnutrition is a significant risk factor for postoperative infections in patients undergoing oncologic surgery. This study was undertaken to determine if perioperative nutritional supplementation with an immune-enhancing formula is superior to standard formula in the prevention of postoperative infectious complications.

STUDY DESIGN

This was a prospective, randomized, double-blind trial comparing perioperative nutritional supplementation with Impact and standard nutritional formulas.

METHODS

Following stratification, 136 patients undergoing oncologic head and neck surgery were randomly assigned to one of four treatment groups: preoperative/postoperative Impact, postoperative Impact, preoperative/postoperative standard formula, and postoperative standard formula. Outcome measures included laboratory evaluations of nutritional status, infectious and wound healing complications, and duration of hospitalization. Statistical analysis was performed using chi2 or two-tailed Fisher Exact Tests, when appropriate.

RESULTS

Intent-to-treat (P = .02) and actual therapy (P = .04) analyses revealed a significant decrease in the incidence of postoperative infectious complications (all sites) in patients who received Impact. There was no significant difference in wound healing problems or duration of hospitalization. Postoperative measures of nutrition status demonstrated a higher serum albumin (P = .05) in patients who received Impact compared with standard formula.

CONCLUSIONS

Compared with standard formula, perioperative nutritional supplementation with Impact significantly reduced the incidence of infectious complications. The length of hospitalization was significantly prolonged in patients with postoperative infections, suggesting potential cost savings with the use of immune-enhancing formulas such as Impact.

[The immune status indices of patients with local purulent necrotic lesions]

Hypoproteinemia, the lowering of albumin-globulin coefficient, IgG and T-suppressors level, the circulating immune complexes contents increase were revealed while the immunological state investigation in 100 patients with purulent wound. The results obtained witness the necessity of application of immunostimulating and antimicrobic methods, which do not influence an organism negatively (fluorochinolones, for example) in treatment of patients with purulent-necrotic infection.

[Immunological parallels in the use of ultraviolet irradiation of autoblood in patients with suppurative diseases of soft tissue]

Ultraviolet irradiation of autoblood in patients with suppurative diseases of soft tissues increased the titer of specific antibacterial antibodies and the number of antibody-producing cells (APC), which was the most expressed in cases when the erythrocytes and leukocytes were exposed separately. Study of the count of APC during UV exposure showed it to increase 6-8 h after the procedure.

[Effect of alanyl-glutamine in postoperative total parenteral nutrition on postoperative immunosuppression and morbidity. Preliminary results of a prospective randomized study]

The impact of glutamine substitution on postoperative immunosuppression and morbidity was investigated in patients with surgical interventions and total parenteral nutrition in a prospective randomized trial. To analyze immune competence, the expression of CD3, CD4, and CD8 on lymphocytes and of HLA-DR and CD14 on monocytes as well as the plasma levels of IL-6 and IL-10 was evaluated before, 1, 2, 4, and 7 days after surgery. A total of 34 patients have been included (with glutamine: n = 18; without glutamine: n = 16). Patients with glutamine substitution showed decreased systemic inflammation, significant faster compensation for postoperative immunosuppression and a lower incidence of postoperative complications. Patients without postoperative complications showed no significant differences in postoperative immunosuppression.

[Some immunologic aspects in postoperative peritonitis]

Examination of blood serum and cellular elements of 45 patients with postoperative diffuse purulent peritonitis shows that in the majority of examined persons before and in the first days after the operation immunodepression exists. The dynamics of immunologic disturbances (antibody titers, phagocytosis, immunoglobulines, T- and B-lymphocytes) are sufficiently informative and as a rule, correlate with clinical course of peritonitis. Adequate reaction of the organism to infection resulted in a favourable outcome. Low values of immunologic indices in postoperative period necessitate the use of stimulant therapy in combined treatment of this complication.

Cimetidine reduces impairment of cellular immunity after cardiac operations with cardiopulmonary bypass

OBJECTIVE

Depressive effects of cardiopulmonary bypass on cell-mediated immune responses may lead to postoperative infectious complications. We previously reported that cimetidine reduced postbypass depression of the cytotoxic activity of natural killer cells. This study evaluated cimetidine as an agent to preserve cellular immunity after cardiac operations.

METHODS

In a prospective randomized study, 20 patients were divided into two groups of equal size. Cimetidine-group patients received 400 mg of cimetidine intravenously before bypass and a 33 mg/hr intravenous infusion of cimetidine after the operation, continuing until the fifth postoperative day. Control-group patients received conventional perioperative therapy. Lymphocyte subsets, natural killer cell activity, percentage of CD56+CD16+ (percentage of natural killer cells), and percentage of CD11b+CD8+ (percentage of suppressor T lymphocytes) were measured perioperatively.

RESULTS

Although temporary postoperative reductions in percentages of CD3+, CD4+, and CD56+CD16+ cells were observed in both groups, CD8+ percentages on postoperative day 1 and CD11b+CD8+ percentages on postoperative days 1 and 3 in the cimetidine group were significantly lower compared with those in the control group (p = 0.01,p = 0.004, andp = 0.02, respectively). Temporary postoperative reduction of natural killer cell activity was also observed in both groups, but the natural killer cell activity on postoperative day 1 in the cimetidine group (17.1%) was significantly higher (p = 0.02) than that in the control group (8.20%).

CONCLUSIONS

Cimetidine counteracts depressive effects of cardiopulmonary bypass on cell-mediated immunity and may possibly reduce postoperative susceptibility to infection.

Infective complications after abdominal surgery in patients infected with human immunodeficiency virus: role of CD4+ lymphocytes in prognosis

Risk factors associated with surgical infections are related to many events that modulate the immune system and affect the surgical procedure. The aim of this study was to determine the influence of low CD4+ lymphocyte counts in 24 patients with human immunodeficiency virus (HIV) undergoing abdominal surgery. Blood samples were obtained, and the lymphocyte population was evaluated perioperatively, as was the nutritional status of the patient. All the patients received selective antibiotic prophylaxis depending on the surgical procedure performed: (1) clean surgery: splenectomies (n = 8); (2) clean-contaminated: cholecystectomy and biliary tract surgery (n = 8); and (3) contaminated: appendectomy (n = 8). Depending on their CD4 count, two groups were formed: one with 200 to 500 cells/ml (n = 11) and the other with < 200 cells/ml (n = 13). When surgical infection was suspected, surgical drainage and microbiologic cultures were undertaken. For statistical evaluation of the groups ANOVA and the chi-square test were used; p < 0.05 was considered significant. Altogether 14 patients (58.3%) had a wound infection, and the mean (+/- SD) CD4 count in those patients was decreased (221.7 +/- 75.1) compared with that of the 10 patients in the uneventful group (386 +/- 81.2). Surgical infection rates were 50% for clean procedures, 62.5% for clean-contaminated procedures, and 62.5% for contaminated surgery. The group of patients with CD4 counts of < 200 cell/ml had an increased incidence of surgical infection, regardless of the type of surgery (p = 0.002). Thus the surgical infection rates with HIV patients undergoing abdominal surgery are dramatically increased. The CD4 and subsequently depressed neutrophil populations increase the risk of surgical infection during major procedures regardless of the type of surgery performed.

[Clinical and laboratory study of cefodizime (Modivid) in prophylaxis and treatment of surgical patients]

The results of the clinical and laboratory study of the efficacy of the prophylactic and therapeutic use of cefodizime (modivid) in patients with chronic calculous cholecystitis and burns are presented. Expediency of the preoperative prophylactic use of the drug and its significance in the treatment of infectious complications of the burn disease were verified. The immunological investigation gave evidence of an increase of the phagocytosis functional activity when cefodizime (modivid) was used prophylactically in cholecystectomy.

Impact of laparoscopic surgery on stress responses, immunofunction, and risk of infectious complications

Open laparotomy is followed by profound changes in endocrine metabolic function and various host defense mechanisms, impaired pulmonary function, and hypoxemia, all of which may be important for the development of postoperative infectious complications. Laparoscopic surgery, however, leads to a reduced inflammatory response (C-reactive protein and interleukin-6), a reduced immunomodulatory response, improvement in pulmonary function, and less hypoxemia, whereas classic endocrine metabolic responses are less influenced or not influenced compared with similar open operation. The clinical implications of laparoscopic surgery on postoperative infectious complications have not been assessed in large-scale prospective, randomized studies, except in appendectomy, in which a reduced incidence of wound infection has been demonstrated. Data from cholecystectomy and colorectal surgery suggest a reduction in wound complications, whereas the sparse data on intraperitoneal infections and sepsis are not conclusive. Thus, laparoscopic surgery modifies the injury response and reduces the risk of infectious complications. If integrated into an accelerated rehabilitation program, further improvement may result. The impact of these findings on prophylactic antibiotic regimens cannot be assessed from available data and requires evaluation in prospective clinical studies.

Molecular mechanisms of sepsis

Today a great number of problems in the field of bacterial sepsis remain to be solved. Understanding the molecular mechanisms of one of the most important bacterial products in the pathogenesis of sepsis - endotoxin may contribute to innovative and more effective therapies. Therefore, this review focuses on the structural and functional elements of endotoxin, its interaction with immune cells, and its biological activity. Finally, other bacterial components and their impact on sepsis are discussed.

Reduced TNFalpha and IL-6 production in patients who mount a preoperative acute phase response

BACKGROUND/AIMS

In some patients postoperative infective complications are related to a reduced resistance to the operative trauma and the perioperative microbiological challenge. To investigate preoperative alterations in the immune responses in patients who had mounted an acute-phase response before the operation, we measured the capacity of tumor necrosis factor alpha and interleukin-6 production in whole blood.

PATIENTS/METHODS

Serum concentrations of C-reactive protein, alpha1-antitrypsin, albumin, and prealbumin were measured in 89 patients submitted for major abdominal surgery on their admission to hospital.

RESULTS

In 23 patients (26%) we found concentrations of at least one, and in 16 patients (18%) of two or more of these variables beyond the reference range. Patients who mounted an acute-phase response released 37% less TNFalpha (1339 vs. 848 pg/ml) and 31% less IL-6 (24293 vs. 16900 pg/ml) when whole blood was stimulated with lipopolysaccharide 0.5 microg/ml.

CONCLUSION

Patients who mount an acute-phase response before operation may thus have a downregulated immune response at the level of proinflammatory cytokines. This is likely to alter their resistance to invasive micro-organisms in the perioperative period.

[Respiratory burst and phagocytosis activity in patients with infection after surgical abdominal interventions]

Phagocyte functions such as respiratory burst or phagocytic activity allow the determination of septic courses. Already in case of surgical stress a reduced constitutive generation of reactive oxygen metabolites could be shown, which is assumed to influence the outcome of following septic courses. The results of septic patients suggest that in spite of a functioning uptake of particles and germs (phagocytosis) a defect of intracellular killing (respiratory burst) exists.

New arguments to explain the high infection rate in posttraumatic spleenless patients

To get more information about the high infection rate in splenectomized adult patients 211 spleenless patients were investigated with regard to clinical and laboratory data and compared to healthy blood donors. The results show that the infection rate is markedly increased to 30%. Splenectomized patients have decreased IgG levels which is due to diminished IgG1 and IgG4. Whereas IgA, complement factors C3, C4, and transferrin are not changed in patients without spleen, fibronectin and IgM are significantly reduced and the phagocytosis as well as the migration of neutrophilic granulocytes is impaired to 50%. With these changes in laboratory data it is possible to identify patients which bear an increased risk with regard to infection.

Perioperative transfusion, postoperative infection, and recurrence of head and neck cancer

BACKGROUND

Immunologic effects of perioperative transfusion and postoperative infection have been purported to influence cancer recurrence rates.

METHODS

Records of all head and neck cancer patients having surgical extirpation of the primary tumor and/or regional nodes at our institution over a 5-year period were reviewed. Time to recurrence was the outcome measure. All variables were evaluated via univariate analysis using log rank tests, with Cox proportional hazards used for multivariate analyses.

RESULTS

Univariate analysis identified the following as potential prognostic factors associated with recurrence: nodal stage, total lymphocyte count, overall stage, amount transfused, occurrence of a transfusion, and the American Society of Anesthesiologists status. Various backward stepwise multivariate regression models showed that neither transfusion nor postoperative infection independently influenced recurrence. However, transfusion of 3 or more units did surface as an independent contributor to recurrence, and in certain subgroups there was a trend toward improved survival for those who had a postoperative infection.

CONCLUSIONS

In this series, neither perioperative transfusion nor postoperative infection independently influenced recurrence.

Surgical wound infection in renal transplantation: outcome data in 102 consecutive patients without perioperative systemic antibiotic coverage

BACKGROUND

The incidence of surgical wound infection in the presence of immunosuppression has been reported in the literature to approach 7%. Perioperative systemic antibiotic therapy is routinely used to reduce the occurrence of wound infections. This therapy is not without complications, including adverse effects and development of resistant strains.

DESIGN

Surgical wound infection rates during the first 100 days after renal transplantation were studied in 102 consecutive patients. Eighty-one patients underwent cadaveric transplantation and 21 patients underwent living-related donor transplantation from February 1, 1991, to January 1, 1992. No systemic perioperative antibiotic coverage was used, but local antibiotic irrigation was part of the perioperative protocol.

SETTING

Hahnemann University Hospital, Philadelphia, Pa, is a large, tertiary care center. Patients were initially hospitalized and were discharged during the 100-day follow-up period based on clinical status and improvement in renal function.

PATIENTS

Twenty-seven (25%) of 102 patients had diabetes mellitus.

INTERVENTIONS

Induction immunosuppression consisted of azathioprine, prednisone, and anitlymphocyte globulin, while maintenance immunosuppression consisted of azathioprine, prednisone, and cyclosporine. Acute allograft rejection episodes were treated with steroids and/or OKT3 (Ortho Pharmaceutical Group, Raritan, NJ).

RESULTS

Two surgical wound infections (2%) occurred. In both, infection was superficial, resolving with wound drainage and intravenous antibiotics. The surgical wound infection rate was not significantly affected by age, sex, allograft source, or presence of diabetes mellitus.

CONCLUSIONS

Despite immunosuppression, the incidence of surgical wound infection was minimal, comparing favorably to rates reported for renal transplantation with the use of systemic antibiotics. Possible explanations for the low incidence of surgical wound infections include local wound irrigation, meticulous hemostasis, improved organ procurement techniques, and continuity in perioperative care.

Antibiotic prophylaxis and infection resistance of massive tumor endoprostheses during chemotherapy

Fifty-five consecutively treated patients with malignant bone tumors had preoperative and postoperative chemotherapy by one oncologist. These same patients had massive bone resection and cemented endoprosthetic bone replacement by one orthopaedic oncologist. Despite 143 instances of documented fever and/or neutropenia in 45 of these 55 patients, no known deep periprosthetic infections developed in any patient during follow-up (mean, 29.4 months; median, 25 months; range, 5 months to 62 months). Broad spectrum antibiotics had been administered in at least 118 instances to these patients (intravenously in hospital, 9 times to 7 patients; intravenously at home, 38 times to 18 patients; and orally at home, 71 times to 26 patients). This study confirms the low infection rate of these massive endoprostheses, despite neutropenic and/or febrile episodes if the patient is given prophylactic broad spectrum antibiotics during the episodes. We support the continued use of massive endoprostheses for bone reconstruction in patients requiring chemotherapy.

Immunoglobulin prophylaxis in shunt infections: a prospective randomized study

Cerebrospinal fluid shunt infection is serious and one of the most frequent complications of shunt implantation. Age has been one of the most significant host factors for the development of shunt infections. A relative deficiency of the immune response against bacteria in infants could partly explain the higher infection rate in the very young patients. This prospective-randomized study was conducted in two groups: group A (immunoglobulin group) and group B (control group). There were 30 patients in each group. The patients in group A received intravenous immunoglobulin (Sandoglobulin) at a dose of 1 g/kg in the night before surgery. Each patient was followed up to 6 months. No infection was seen in group A. In group B, infection rate per procedure were 5.1% (P = 0.494) and 6.6% (P = 0.492), respectively. Intravenous immunoglobulin prophylaxis in infants seems to reduce the shunt infections.

[The intracorporeal ultraviolet irradiation of the blood and its effect on the immune status in patients with a surgical infection]

A dynamic investigation was done of the immunologic status in 75 patients with purulent surgical lesions of soft tissues. Applied in the complex of therapeutic measures was intracorporeal irradiation of blood with ultraviolet light under control of partial pressure of oxygen and carbon dioxide. The above irradiation was found out to make for a more rapid and marked stabilization of bodily immunologic status.

[Surgery in immunosuppressed patients with emergency or elective indications]

Immunosuppressive therapy and its influence on perioperative pathophysiology present special challenges in the event of surgical intervention. Immunosuppressive agents alter the patient's response to surgical stress and infectious complications. The often masked signs, even in the case of severe infection, require a high index of suspicion to establish the diagnosis. This may result in a fatal delay of therapy. In addition, the immunosuppressed state increases the patient's susceptibility to infection and leads to an impairment of wound healing. Therefore, careful perioperative clinical monitoring of the patient and complete control of the immunosuppressive therapy are mandatory. Elective operations in immunosuppressed patients should be performed with special caution regarding the potential perioperative risks for the patient and the graft. On the other hand, if there is evidence of, for example, an acute abdominal event, a more aggressive approach is required to rapidly establish the diagnosis and institute appropriate therapy. From the surgical point of view, special emphasis should be placed on wound closure and on anastomotic sutures when operating on a patient receiving immunosuppressive therapy.

Impact of splenectomy on circulating immunoglobulin levels and the development of postoperative infection following total gastrectomy for gastric cancer

Splenectomy increases the postoperative morbidity of total gastrectomy for carcinoma of the stomach. The reasons for this increased risk of postoperative infection are unknown. The aim of this study was to evaluate the impact of splenectomy on circulating immunoglobulin levels and to determine whether splenectomy was an independent risk factor for the development of postoperative infection in 154 patients undergoing total gastrectomy for carcinoma of the stomach. Splenectomy reduced circulating immunoglobulin M levels in the early postoperative period following total gastrectomy. However, it was not identified as an independent risk factor for the development of postoperative infection by multivariate analysis.

Inhibition of T and B cell proliferation by titanium, cobalt, and chromium: role of IL-2 and IL-6

The mechanism by which an increased risk of prosthetic infection is induced in patients with total joint arthroplasties is poorly understood. The adverse effects of metallic corrosion products of a prosthesis on host defense mechanisms, particularly immune response and release of immunoregulatory cytokines, remain largely unknown. Titanium, cobalt, and chromium are the materials most often used for joint implantation. Therefore, this study was aimed at investigating the cytotoxicity of titanium, cobalt, and chromium and whether these metals affect T and B cell proliferation and the release of cytokines by human peripheral blood mononuclear cells (PBMC) in vitro. Metal cytotoxicity was not observed judging by cell viability and cell injury after PBMC was extensively exposed to the metals. Phytohemagglutinin (PHA)-induced T cell proliferation and lipopolysaccharide-induced B cell proliferation were significantly inhibited by titanium, chromium, and cobalt. The release of IL-2 and IL-6 by PHA-stimulated PBMC was significantly inhibited by titanium, chromium, and cobalt. Titanium did not alter IFN-gamma production, whereas chromium and cobalt significantly reduced IFN-gamma release by PHA-stimulated PBMC. The addition of IL-2 and IL-6 significantly restored the metal-induced inhibition of T cell and B cell proliferation, respectively. This study sheds light on how the metals impair immune response and cytokine release, suggesting that patients with an extensive exposure to the metals may develop immune dysfunctions. The compromised immune response induced by the metals might significantly contribute to an increased risk of infection in patients with joint prostheses.