Hemodilution and coagulation. An overview.

Review of adverse effects related to perioperative hemodilution with specific reference to modulation of hemostasis. Relevant studies were obtained from the medical literature. Artificial colloids impair hemostasis in a specific way, especially when given to patients with a congenital alteration of platelet function such as a mild form of von Willebrand disease.

Blunted erythropoietic response to anemia in multiply traumatized patients.

OBJECTIVES: To assess the relations between anemia, serum erythropoietin (EPO), iron status, and inflammatory mediators in multiply traumatized patients. DESIGN: Prospective observational study. SETTING: Intensive care unit. PATIENTS: Twenty-three patients suffering from severe trauma (injury severity score > or =30). INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Blood samples were collected within 12 hrs after the accident (day 1) and in the morning on days 2, 4, 6, and 9 to determine blood cell status, serum EPO, tumor necrosis factor-alpha (TNF-alpha), soluble tumor necrosis factor-receptor I (sTNF-rI), interleukin-1 receptor antagonist (IL1-ra), interleukin-6 (IL-6), neopterin, and iron status, respectively. Hemoglobin concentration was low at admission (mean, 10.0 g/dL; range, 6.8-12.9 g/dL) and did not increase during the observation time. Serum EPO concentration was 49.8 U/L (mean value) on day 1 and did not show significant increases thereafter. No correlation was found between EPO and hemoglobin concentrations. TNF-alpha remained within the normal range. sTNF-rI was high at admission and increased further. IL1-ra was above the normal range. IL-6 was very high at admission and did not decrease thereafter. The initial neopterin concentration was normal, but increased until day 9. Serum iron was significantly decreased on day 2 posttrauma and remained low during the study. Serum ferritin increased steadily from day 2, reaching its maximum on day 9. In contrast, concentrations of transferrin were low from admission onward. CONCLUSIONS: Multiply traumatized patients exhibit an inadequate EPO response to low hemoglobin concentrations. Thus, anemia in severe trauma is the result of a complex network of bleeding, blunted EPO response to low hemoglobin concentrations, inflammatory mediators, and a hypoferremic state.

Low platelet count and elevated serum thrombopoietin after severe trauma.

Platelet count is regularly low in patients after multiple trauma, mainly due to blood loss and dilution. Thrombopoietin (TPO) is the main regulator of the circulating platelet mass. Under several clinical conditions an inverse correlation between TPO and the circulating platelet mass was reported. Since platelets bind and internalize TPO, a platelet-dependent regulation of TPO was suggested. Thus, acute blood loss should be accompanied by elevated TPO. We measured serum TPO, platelets, interleukin-6 (IL-6) and vascular endothelial growth factor (VEGF) in 17 multiple traumatized victims. Blood was collected within 12 h after trauma as well as in the morning of days 2, 4, 6 and 9 after admission at the intensive care unit. Platelet count was low at admission and remained low until day 4. Thereafter platelets increased until day 9. TPO nearly doubled within the first 2 d, reaching its maximum on day 6. IL-6 was initially very high and steadily decreased until day 9. VEGF increased 3-fold during the 9 d. Statistically significant correlations of TPO were found with platelets and IL-6, but not with VEGF. In multiple traumatized patients low platelet count is followed by a rapid increase in serum TPO. This fits into the concept of a feedback regulation between circulating TPO and platelet mass.

Immunologic changes after transfusion of autologous or allogeneic buffy coat-poor versus WBC-reduced blood transfusions in patients undergoing arthroplasty. II. Activation of T cells, macrophages, and cell-mediated lympholysis.

BACKGROUND: To estimate the impact of RBC preparations on the status of postoperative immune activation, the soluble cytokine receptors of TNFalpha (sTNF-R) and IL-2 (sIL-2R), as well as neopterin and cell-mediated lympholysis (CML), were measured. STUDY DESIGN AND METHODS: Patients undergoing strictly standardized anesthesiologic management for elective orthopedic surgery were enrolled in a prospective study. The perioperative course (Days 0, 3, 7, and 10) of sTNF-R, sIL-2R, neopterin, and CML was compared after random assignment to allogeneic buffy coat-reduced (Group 2, n = 8) or WBC-reduced (Group 3, n = 11) RBC transfusion regimen. Recipients of autologous buffy coat-reduced RBC transfusions (Group 1, n = 15) served as controls. Patients receiving intraoperatively and postoperatively salvaged blood only (n = 10) were separately analyzed as Group 4. RESULTS: In Group 1, a short-lasting increase in soluble cytokine receptors, a diminished cytolytic response (Day 0 vs. Day 7: sTNF-R, p = 0.0001; sIL-2R, p = 0.0004; CML, p = 0. 0238), and an elevation of neopterin (Day 0 vs. Day 3: p = 0.0064) were observed. In contrast, in allogeneically transfused patients, sTNF-R (Group 2, p = 0.0469: Group 3, p = 0.0039), sIL-2R (Group 3, p = 0.002) and neopterin (Group 3, p = 0.0164) increased further from baseline to Day 10 (Day 0 vs. Day 10), and this increase was accompanied by a diminished cytolytic response (Day 0 vs. Day 10: Group 2, p = 0.05; Group 3, p = 0.0076). Patients in Group 4 showed a short-lasting increase in sIL-2R (Day 0 vs. Day 3: p = 0.0078), neopterin (Day 0 vs. Day 3: p = 0.0156) and sTNF-R (Day 0 vs. Day 7: p = 0.0781). CONCLUSION: Allogeneic transfusions seem to prolong the postoperative status of immune activation, even when WBC-filtered RBCs are used for the transfusion regimen.

Increase in immune activation, vascular endothelial growth factor and erythropoietin after an ultramarathon run at moderate altitude.

The present study was performed to investigate the effects of exhaustive long lasting exercise at moderate altitude on the time course of serum immunomodulatory peptides, vascular endothelial growth factor (VEGF) and serum erythropoietin (EPO). Thirteen well trained runners participated at the Swiss Alpine Marathon of Davos (distance 67 km, altitude difference 2300 m). Interleukin-6 was significantly elevated in the first 2h after the run. In contrast, tumor necrosis factor-alpha and both soluble tumor necrosis factor-a receptors I and II were increased after exercise termination and showed sustained serum concentrations the following days. Neopterin, a serum marker for the activation of the cellular immune system, was increased until day two after the run. Immediately after the run VEGF was significantly elevated and further increased 2.4-fold until day five post exercise (p = 0.005). EPO was also increased after exercise but reached its maximum 2 h after the run (2-fold increase; p = 0.004) and decreased thereafter. The main findings of our study are that prolonged strenuous exercise at moderate altitude induced a significant long lasting increase in serum VEGF and EPO which was accompanied by an activation of the immune system.

Immunologic changes after transfusion of autologous or allogeneic buffy coat-poor versus white cell-reduced blood to patients undergoing arthroplasty. I. Proliferative T-cell responses and the balance of helper and suppressor T cells.

BACKGROUND: Donor white cells (WBCs) contained in red cell (RBC) transfusions are thought to provoke down-regulation of T-cell-mediated immunity. This study investigated this topic in otherwise healthy patients receiving buffy coat-depleted or WBC-filtered RBCs and undergoing standardized perioperative management. STUDY DESIGN AND METHODS: Patients undergoing elective orthopedic surgery (primary hip and knee replacement surgery) were enrolled in a prospective study. Perioperative changes in T-cell proliferation (stimulation with phytohemagglutinin and mixed lymphocyte culture) and T-cell balance (T-lymphocytes, helper T cells, and suppressor T cells) were compared after random assignment to allogeneic buffy coat-depleted (Group 2, n = 8) or WBC-reduced RBC (Group 3, n = 11) transfusion regimens. Recipients of autologous buffy coat-depleted RBC transfusions (n = 15) served as controls (Group 1). RESULTS: Compared to that in autologous transfusion recipients, alloantigen-induced T-cell proliferation was significantly reduced in recipients of allogeneic WBC-reduced RBCs (Day 3, p = 0.0274). After the transfusion of allogeneic buffy coat-depleted RBCs, a weak trend toward decreased T-cell proliferation was observed (p = 0.0933) and the numbers of CD4+ T cells were also significantly lower (Day 7, p = 0.0389). On Day 10, alloantigen-induced T-cell proliferation remained significantly below baseline after transfusion of WBC-reduced RBCs (p = 0.05), the numbers of CD3+ cells decreased in allogeneic RBC recipients (Group 2, p = 0.078; Group 3, p = 0.05), and those of CD8+ cells decreased significantly after the transfusion of allogeneic buffy coat-depleted RBCs (p = 0.0234) concomitant with an increased CD4:CD8 ratio (p = 0.0391). CONCLUSION: Results of the present study confirm the hypothesis of impaired T-cell-mediated immunity after allogeneic transfusion.

Consequences of acute normovolaemic haemodilution on haemostasis during major orthopaedic surgery.

Acute preoperative normovolaemic haemodilution (NHD) is an accepted tool for reducing allogeneic blood transfusion requirements during surgery. At present, little is known of its impact on haemostasis. We have investigated the consequences of NHD on haemostasis by comparing conventional global tests (prothrombin time (PT), activated partial thromboplastin time (aPTT) with more specific measures of coagulation (prothrombin fragment 1 + 2 (F 1 + 2), thrombin-antithrombin III complex (TAT) and fibrinolysis (D-dimer (DD), plasmin-alpha 2-antiplasmin complex (PAP)). Blood samples were collected from two groups (NHD and controls) undergoing elective spinal surgery or pelvic osteotomy until day 3 after operation. The conventional global tests remained within normal limits: there were no significant differences between groups. Although surgery induced significant increases in the more specific measures of coagulation and fibrinolysis, there were no differences between NHD and control patients. Major orthopaedic surgery strongly activates coagulation and fibrinolysis. As the degree of these alterations was similar in haemodiluted and control patients, we suggest that acute preoperative normovolaemic haemodilution itself does not appear to be associated with greater perioperative disturbances in haemostasis.

Transfusion of buffy coat-depleted blood components and risk of postoperative infection in orthopedic patients.

BACKGROUND: Allogeneic blood transfusions have been reported to increase susceptibility to postoperative infection, but the findings were inconclusive. This study was designed to investigate the effect of buffy coat-depleted allogeneic and autologous transfusion on postoperative infection in patients undergoing orthopedic surgery. STUDY DESIGN AND METHODS: Patients (n = 385) undergoing elective orthopedic surgery (primary and revision joint replacement, spinal, or pelvic surgery) were included in a prospective observational study of the incidence of postoperative infection between April and December 1996. Infection rates in patients who received allogeneic buffy coat-depleted blood transfusions were compared with those in patients who received no transfusion or only autologous (buffy coat-depleted) blood. RESULTS: Patients without exposure to allogeneic blood (no blood or only autologous blood) had an infection rate of 3.9 percent, as compared to a rate of 12.2 percent for those with exposure to allogeneic blood (allogeneic blood, autologous plus allogeneic blood) (odds ratio 3.442; 95% CI, 1.349-10.40; p = 0.006). Of the 385 study patients, 309 underwent primary hip or knee replacement surgery. In this homogeneous subgroup, the postoperative infection rate was 4.6 percent after no transfusion or autologous transfusion and 11.9 percent after allogeneic transfusion (odds ratio 2.827; 95% CI 1.059-8.799; p = 0.036). Multivariate regression analysis confirmed buffy coat-depleted allogeneic blood transfusion as an independent variable associated with high risk for postoperative infection. CONCLUSION: Buffy coat-depleted allogeneic blood transfusion increases the incidence of postoperative infection in patients undergoing uncontaminated orthopedic surgery.

Angiotropic large B-cell lymphoma misdiagnosed as urosepsis with multiple organ dysfunction syndrome.

A 53-year-old woman with a history of cervical carcinoma 14 years ago, treated with hysterectomy and radiation therapy, was admitted to the intensive care unit with severe SIRS (systemic inflammatory response syndrome) progressing to shock, multiple organ failure and death within 5 d. Bilateral hydronephrosis diagnosed by sonography and an enlarged left kidney with suspected abscesses verified in a CT-scan suggested the diagnosis of urosepsis. However, multiple microbiological examinations remained sterile. Despite surgical treatment and aggressive intensive care, she died in unresponsive shock. Pathohistologically, an angiotropic large B-cell lymphoma, a rare diffuse intravascular neoplasm of lymphoid origin, was diagnosed. The patient's history of abdominal radiation therapy 14 years earlier as well as multiple negative microbiological specimens in a patient with suspected urosepsis should have initiated the search for a non-infectious cause of the disease.

No release of cardiac troponin I during major orthopedic surgery after acute normovolemic hemodilution.

BACKGROUND: Normovolemic hemodilution is a well-accepted method for intraoperative blood salvage. However, some controversy exists concerning the possible risk of myocardial fiber injury as consequence of the reduced oxygen content. Laboratory diagnosis of perioperative myocardial fiber injury is difficult, since biochemical markers are elevated postoperatively due to the surgical trauma. Cardiac troponin I (cTnI) is a new, highly sensitive and specific marker for the detection of myocardial injury. The aim of our study was to investigate whether normovolemic hemodilution in patients with major orthopedic surgery (13 hemodiluted patients, 15 control) induces a release of cTnI. METHODS: cTnI as a highly specific and sensitive cardiac parameter, as well as total creatine kinase (CK), creatine kinase isoenzyme MB mass (CKMB mass) and myoglobin were measured after induction of anesthesia, after normovolemic hemodilution, prior to retransfusion of blood components, 3 h after surgery, and on the first and third postoperative days. RESULTS: Prior to retransfusion of blood components the hematocrit was decreased to 25.4 +/- 1.2% (mean +/- SEM; range: 18%-34%) in the control group and to 20.2 +/- 0.8% (mean +/- SEM; range: 17%-24%) in the hemodilution group. Total CK, CKMB mass as well as myoglobin concentration increased significantly in both groups, reaching their maxima within the first day of surgery. In contrast, cTnI was below the detection limit of assay (< 0.5 micrograms/L) at any time. CONCLUSIONS: We suggest that pre- and intraoperative hemodilution to a hematocrit of approximately 20% by maintaining normovolemia does not induce myocardial fiber injury in patients without preexisting cardiac diseases.

Metastatic lesions from prostate cancer do not express oestrogen and progesterone receptors.

Oestrogen receptors (ER) and progesterone receptors (PR) have been reported by several authors in the stromal cells of the human prostate. Controversial results exist on the expression of ER and PR in epithelial cells of the prostate. Some recent publications, in contrast to previous findings, have suggested that these receptors are also present in human prostate cancer cell lines derived from metastatic lesions. The expression of ER and PR in these cell lines has been re-examined to determine their presence in lymph node metastases from patients who did not receive any kind of endocrine therapy and in distant metastases obtained from patients who failed endocrine treatment. ER and PR expression in LNCaP, PC-3, and DU-145 cells was assessed by means of the reverse transcriptase-polymerase chain reaction, ligand binding assays, and immunohistochemistry. With all the techniques applied, the three cell lines were found to be negative for both ER and PR. Immunohistochemical analyses were performed in four lymph node metastases obtained at radical prostatectomy from patients who did not receive endocrine therapy and in 17 distant metastases obtained at palliative surgery from patients who failed endocrine therapy. All 21 metastases were negative for ER and PR on immunohistochemistry. These results do not support the recently developed concept that receptors for oestrogenic and progestagenic steroids are present in metastases from human prostate cancer.

Neopterin and 7,8-dihydroneopterin induce apoptosis in the rat alveolar epithelial cell line L2.

The neopterin derivatives, neopterin and 7,8-dihydroneopterin, modulate the cellular oxidant-antioxidant balance as well as the expression of the inducible nitric oxide synthase (iNOS) gene. Since apoptosis can be induced by reactive oxygen intermediates and nitric oxide (NO) we investigated whether these neopterin derivatives induce apoptotic cell death. As model we selected the rat alveolar epithelial cell line L2. 24 h incubation of neopterin (1-1000 microM) as well as 7,8-dihydroneopterin (1-1000 microM) resulted in a significant increase of percent apoptotic cells (measured by FACS analysis). Coincubation of both pteridines with the cytomix (interferon-gamma plus tumor necrosis factor-alpha) led to a significantly higher apoptosis than the cytomix alone. In contrast to the cytomix, no iNOS gene expression and no NO release could be detected after incubation with neopterin or 7,8-dihydroneopterin. We conclude that neopterin and 7,8-dihydroneopterin are per se inducers of apoptosis which is not mediated by nitric oxide. This may be of importance in inflammatory pulmonary diseases associated with an activation of the cellular immune system.