Factores asociados a coagulopatías adquiridas en una unidad de cuidados intensivos / Factors Associated with Acquired Coagulopathies in an Intensive Care Unit

Introducción: en los pacientes críticos existe un desequilibrio entre las actividades procoagulantes y las anticoagulantes, por ello las alteraciones de la coagulación o coagulopatías son una complicación frecuente que se asocia con una elevada morbilidad y mortalidad. Objetivos: identificar factores de riesgo asociados con coagulopatías adquiridas en pacientes ingresados y analizar la relación entre coagulopatía y mortalidad. Métodos: se realizó un estudio longitudinal prospectivo, donde se revisaron complementarios e historias clínicas de 29 pacientes ingresados en la unidad de cuidados intensivos del hospital Hermanos Ameijeiras, desde abril hasta junio de 2011. Se identificaron factores de riesgo asociados a las coagulopatías y se analizó su relación con la mortalidad. Resultados: se identificó la presencia de coagulopatías al ingreso en 58,62 por ciento, entre las 48-72 h 44,82 por ciento y en la última evaluación 51,73 por ciento. Predominó la coagulopatía por deficiencia de factores dependientes de vitamina K. Dentro de la unidad, el uso de hemocomponentes y la administración de aminoglucósidos resultaron estadísticamente significativos. Fallecieron 21 de los pacientes y en 13 de ellos se detectó la presencia de coagulopatía representando 44,8 por ciento. Conclusiones: se detectó que es dos veces más probable que a la persona que le administren hemocomponentes desarrolle algún tipo de coagulopatía y 5 veces más probable si se le administran aminoglucósidos. No se encontró relación significativa entre la presencia de coagulopatía y mortalidad, ni relación significativa entre la presencia de sangramiento y mortalidad(AU)

Introduction: There is an imbalance between procoagulant activities and anticoagulants in critical patients, so coagulation disorders or coagulopathies are a frequent complication associated with high morbidity and mortality. Objectives: To identify risk factors associated with acquired coagulopathies in hospitalized patients and to analyze the relationship between coagulopathy and mortality. Methods: A prospective longitudinal study was carried out. Complementary and clinical histories of 29 patients were reviewed. These patients had been admitted to the intensive care unit at Hermanos Ameijeiras hospital from April to June 2011. Risk factors associated with coagulopathies were identified. Mortality relationship was analyzed. Results: The presence of coagulopathies on admission was identified in 58.62 percent, 44.82 percent in 48-72 h and 51.73 percent in last assessment. Coagulopathy was predominant due to deficiency of vitamin K dependent factors. The use of blood components and the administration of aminoglycosides were statistically significant in the unit. Twenty one (21) patients died and thirteen (13) coagulopathy was detected, (44.8 percent). Conclusions: It was detected that it is twice as likely that the person receiving hemocomponents will develop some type of coagulopathy and five times more likely if they are administered aminoglycosides. No significant relationship was found between the presence of coagulopathy and mortality, nor significant relationship between the presence of bleeding and mortality(AU)

Factores asociados a coagulopatías adquiridas en una unidad de cuidados intensivos / Factors Associated with Acquired Coagulopathies in an Intensive Care Unit

Introducción: en los pacientes críticos existe un desequilibrio entre las actividades procoagulantes y las anticoagulantes, por ello las alteraciones de la coagulación o coagulopatías son una complicación frecuente que se asocia con una elevada morbilidad y mortalidad. Objetivos: identificar factores de riesgo asociados con coagulopatías adquiridas en pacientes ingresados y analizar la relación entre coagulopatía y mortalidad. Métodos: se realizó un estudio longitudinal prospectivo, donde se revisaron complementarios e historias clínicas de 29 pacientes ingresados en la unidad de cuidados intensivos del hospital Hermanos Ameijeiras, desde abril hasta junio de 2011. Se identificaron factores de riesgo asociados a las coagulopatías y se analizó su relación con la mortalidad. Resultados: se identificó la presencia de coagulopatías al ingreso en 58,62 por ciento, entre las 48-72 h 44,82 por ciento y en la última evaluación 51,73 por ciento. Predominó la coagulopatía por deficiencia de factores dependientes de vitamina K. Dentro de la unidad, el uso de hemocomponentes y la administración de aminoglucósidos resultaron estadísticamente significativos. Fallecieron 21 de los pacientes y en 13 de ellos se detectó la presencia de coagulopatía representando 44,8 por ciento. Conclusiones: se detectó que es dos veces más probable que a la persona que le administren hemocomponentes desarrolle algún tipo de coagulopatía y 5 veces más probable si se le administran aminoglucósidos. No se encontró relación significativa entre la presencia de coagulopatía y mortalidad, ni relación significativa entre la presencia de sangramiento y mortalidad(AU)

Introduction: There is an imbalance between procoagulant activities and anticoagulants in critical patients, so coagulation disorders or coagulopathies are a frequent complication associated with high morbidity and mortality. Objectives: To identify risk factors associated with acquired coagulopathies in hospitalized patients and to analyze the relationship between coagulopathy and mortality. Methods: A prospective longitudinal study was carried out. Complementary and clinical histories of 29 patients were reviewed. These patients had been admitted to the intensive care unit at Hermanos Ameijeiras hospital from April to June 2011. Risk factors associated with coagulopathies were identified. Mortality relationship was analyzed. Results: The presence of coagulopathies on admission was identified in 58.62 percent, 44.82 percent in 48-72 h and 51.73 percent in last assessment. Coagulopathy was predominant due to deficiency of vitamin K dependent factors. The use of blood components and the administration of aminoglycosides were statistically significant in the unit. Twenty one (21) patients died and thirteen (13) coagulopathy was detected, (44.8 percent). Conclusions: It was detected that it is twice as likely that the person receiving hemocomponents will develop some type of coagulopathy and five times more likely if they are administered aminoglycosides. No significant relationship was found between the presence of coagulopathy and mortality, nor significant relationship between the presence of bleeding and mortality(AU)

[Coagulation profiles during cardiac surgery].

OBJECTIVE: To evaluate patients' hemostasis after cardiac surgery using thromboelastometric and impedance aggregometry. MATERIALS AND METHODS: 66 patients were examined intraoperatively. Comparison group included 45 blood donors. Hemostasis was tested for thromboelastometricRotem Gamma with the assessment of external (exTem) and internal (inTem) pathways of coagulation tests performed detection of heparin (hepTem) and cytochalasin-D-inactivation of platelets (fibTem) to assess the level of fibrinogen. Collagen-induced platelet aggregation was determined in an aggregometer CHRONO-LOG (USA). RESULTS: Significant deviations of the parameters of hemostasis were detected in 52 of the 66 studied patients. In group-1 (23 patients) revealed a residual effect of heparin. The effect manifested prolongation CT (clotting time) inTem to an average of 241 +/- 15 s, compared with CT hepTem--181 +/- 7. Patients in this group were in need of additional administration of protamine sulfate. Postoperative bleeding and resternotomia were observed in 3 patients of group-1. In group-2 (25 patients) CT inTem was 216 +/- 21 with significantly fewer CT hepTem (272 +/- 26). The data indicated excess of protamine sulfate. Platelets aggregation decreased compared to the norm. According to the obtained results, the addition of protamine sulfate is not required, however, in 7 cases the protamine sulfate was administered in a dose of 8.9 +/- 0.8 mg in 6 cases resternotomiya required. In the third group (n = 6) bleeding was observed in 4 patients. The difference in CT-hepCT was significant. Significant variations were revealed in the tests of the activity of the extrinsic pathway of coagulation and cytochalasin-D-induced inactivation of platelets: exMCF- 42 +/- 2 mm (normal 57 +/- 15 mm), fibMCF 5.0 +/- 0.3 mm (norm 12.8 +/- 4.3 mm). The concentration of platelets and their aggregation activity was sharply reduced. Disorders of hemostasis in the third group, designated as dilution coagulopathy. CONCLUSION: Turning thromboelastometric and impedance aggregometry in the study of the coagulation profile of patients undergoing cardiac surgery in postperfusion period brings valuable information and allows a differentiated treatment of hemostasis disorders.

Spinal haematoma after removal of a thoracic epidural catheter in a patient with coagulopathy resulting from unexpected vitamin K deficiency.

Postoperative epidural analgesia is effective and widely utilised after major abdominal surgery. Spinal haematoma is a rare and devastating complication after epidural analgesia. Well-established risk factors for the development of spinal haematoma after neuraxial procedures have been documented. We present the case of a patient with normal pre-operative coagulation parameters who developed a spinal haematoma more than 24 h after removal of an epidural catheter; she had been without oral intake for only 4 days during which time she developed vitamin K-deficient coagulopathy. Clinicians should consider pre-operative screening of coagulation (International Normalised Ratio), or giving vitamin K supplementation, before performing neuraxial procedures in patients who are at risk of developing vitamin K deficiency or coagulopathy in the peri-operative period.

[The protective effect of Xuebijing injection pretreatment on hepatic ischemia reperfusion injury and coagulopathy after excision of liver cancer].

OBJECTIVE: To observe the protective effect of Xuebijing injection pretreatment on hepatic ischemia reperfusion (I/R) injury and coagulopathy in liver cancer patients undergoing excision of hepatic cancer after occlusion of hepatic blood flow. METHODS: A prospective randomly controlled study was conducted. Sixty patients with liver cancer classified as Child-Pugh class A undergoing hepatectomy in the Department of Hepatobiliary Surgery of Sun Yat-sen University Cancer Center from October 2011 to March 2013 were enrolled. The patients were randomized into control group and Xuebijing group (each patient received 100 mL Xuebijing injection added to 0.9% saline as a preoperative treatment for 3 days). Complete blood count, coagulation function, hepatic function, serum pro-inflammatory cytokines and alpha-fetoprotein (AFP) levels were determined before and after operation. RESULTS: Forty-five out of 60 patients were enrolled eventually, with 23 patients in control group and 22 in Xuebijing group, and among them 43 patients were positive for hepatitis B surface antigen (HBsAg) at admission. Compared with those before operation, the postoperative levels of alanine transaminase (ALT), aspartate transaminase (AST) and lactate dehydrogenase (LDH) in control and Xuebijing groups were significantly elevated, prothrombin time (PT) and activated partial prothrombin time (AfYIT) were significantly prolonged, and white blood cells (WBC) , proportion of neutrophils (N) and C-reactive protein (CRP) were significantly increased (P<0.05 or P<0.01 ). Although the above indexes in Xuebijing group after operation were lower than those in control group in different degrees [ALT (U/L): 213.1 (80.4-796.6) vs. 265.8 (15.6-882.3), AST (UIL): 194.1 (65.4-914.2) vs. 264.3 (15.4-475.9), LDH (lg,U/L): 5.69 ± 0.72 vs. 5.71 ± 0.72, PT (s): 15.24 ± 2.16 vs. 14.41 ± 1.33, AfYIT (s): 31.51 ± 7.04 vs. 29.47 ± 4.90, WBC (x 109/L) : 13.4 7 ± 4.66 vs. 14.58 ± 4.40, N: 0.87 ± 0.06 vs. 0.87 ± 0.04, CRP (mg/L): 40.64 (16.93-189.59) vs. 45.64 ( 1.65-349.40) J, no statistical significance was found between the groups (all P>0.05 ). The preoperative levels of tumor necrosis factor-a (TNF -a) and interleukin-6 OL-6) were both less than 1.0 ng/L, and the postoperative levels of TNF-a showed no significant change, and IL-6 was increased to 485.10 (104.00-837.50) ng/L and 193.26 (95.10-385.20) ng/L in control and Xuebijing groups respectively (P<0.01). The serum high mobility group box-1 ( HMGB1 ) protein levels after operation were higher than those of preoperative in both groups (both P<0.01), but the postoperative HMGB1 in Xuebijing group were significantly lower than those in control group (j.Lg/L: 268.73 ± 5.56 vs. 277.12 ± 2.92, P<0.01). Acute physiology and chronic health evaluation ll (APACHE ll) score in Xuebijing group was significantly lower than that in control group (4.18 ± 3.75 vs. 4.53 ± 2.34, t=5.328, P=0.027), and the first passage of flatus and defecation after operation in Xuebijing group were significantly earlier than those in control group [exhaust time (days): 3 (2-4) vs. 3 (2-4), U=-2.023, P=0.043; defecation time (days): 4 (2-6) vs. 5 (3-8), U =-2.926, P=0.003 J. However, no difference was found between two groups in the postoperative and total hospital days. Spearman rank correlation analysis showed there were positive correlations between hepatitis B virus (HBV)-DNA levels and preoperative ALT (r=0.414, P=0.044) and AST (r=0.405, P=0.024) in 33 HBV-DNA positive patients, but there was no significant correlation between HBV -DNA levels or other preoperative liver function indicators. CONCLUSIONS: Hepatic I/R injury and coagulopathy may occur in liver cancer patients undergoing resection of cancer with occlusion of hepatic blood flow. Xuebijing injection may inhibit the release of serum pro-inflammatory cytokines, thereby alleviate hepatic I/R injury and promote the recovery of intestinal function. But it does not offer protective effect on coagulopathy.

[Perioperative management of Jehovah's Witness patients. Special consideration of religiously motivated refusal of allogeneic blood transfusion]. / Perioperatives Management bei Zeugen Jehovas. Spezielle Berücksichtigung der religiös motivierten Ablehnung von Fremdblut.

The religious organization of Jehovah's Witnesses numbers more than 7 million members worldwide, including 165,000 members in Germany. Although Jehovah's Witnesses strictly refuse the transfusion of allogeneic red blood cells, platelets and plasma, Jehovah's Witness patients may nevertheless benefit from modern therapeutic concepts including major surgical procedures without facing an excessive risk of death. The present review describes the perioperative management of surgical Jehovah's Witness patients aiming to prevent fatal anemia and coagulopathy. The cornerstones of this concept are 1) education of the patient about blood conservation techniques generally accepted by Jehovah's Witnesses, 2) preoperative optimization of the cardiopulmonary status and correction of preoperative anemia and coagulopathy, 3) perioperative collection of autologous blood, 4) minimization of perioperative blood loss and 5) utilization of the organism's natural anemia tolerance and its acute accentuation in the case of life-threatening anemia.

Role of orally available antagonists of factor Xa in the treatment and prevention of thromboembolic disease: focus on rivaroxaban.

Interpatient variability in the safety and efficacy of oral anticoagulation with warfarin presents several challenges to clinicians, thus underscoring the emergent need for new orally available anticoagulants with predictable pharmacokinetic and pharmacodynamic profiles and ability to target circulating clotting factors. Seven compounds including rivaroxaban, apixaban, betrixaban, and eribaxaban are orally available direct inhibitors of activated factor X currently in development for the prevention and treatment of venous thromboembolism and for thromboprophylaxis in patients with atrial fibrillation or following an acute coronary syndrome. At doses used in phase 2 and 3 clinical trials, rivaroxaban and apixaban demonstrated a predictable onset of effect, maximal plasma concentration, and half-life that was unaffected by age, renal, or hepatic disease. In clinical trials for the treatment and prevention of venous thromboembolism, rivaroxaban and apixaban produced equivalent or superior reductions in the development or progression of venous thromboembolism compared with either low molecular weight heparin or warfarin. Trials comparing the efficacy of rivaroxaban or apixaban to standard therapy for stroke prophylaxis in patients with atrial fibrillation are in process. Rivaroxaban, the sentinel compound in this class, is already approved in the European Union and Canada. It is likely to be approved for use in the United States in 2010.

Transfusion of blood products in trauma: an update.

BACKGROUND: Blood transfusion in the management of severely injured patients can be lifesaving. These patients are susceptible to developing early coagulopathy, thus perpetuating bleeding. OBJECTIVES: This article presents recent advances in both the civilian and military clinical arena to improve the treatment of trauma patients with severe hemorrhage, the use of agents to support coagulation, perspectives on restrictive transfusion strategies, and transfusion-related risks. DISCUSSION: Massive blood transfusion is an adjunct to surgical care. The volume of blood products transfused and the ratio of blood components have been associated with increased morbidity and mortality rates. The adverse clinical effects of transfusion and the limited supply of blood products have resulted in modern resuscitation protocols to limit the volume of blood transfused. CONCLUSION: A restrictive blood transfusion strategy and the use of hemostatic agents may decrease morbidity and mortality in trauma patients, but insufficient data are available for their use in trauma patients. Massive transfusion should reflect an equal ratio of packed red cells and plasma to limit coagulopathy. Prospective randomized trials are needed to standardize an effective protocol.

Hyperbaric oxygen therapy prevents coagulation disorders in an experimental model of multiple organ failure syndrome.

OBJECTIVE: To evaluate the effects of hyperbaric oxygen (HBO) therapy on the coagulation cascade using an experimental model of multiple organ failure syndrome (MOFS). DESIGN: MOFS was induced by zymosan (500mg/kg i.p.) in rats. HBO therapy (2ATA) was administered in a cylindrical steel chamber 4 and 11h after zymosan administration. In a separate set of experiments animals were monitored for 72h, and systemic toxicity was scored. INTERVENTION: Eighteen hours after zymosan administration, rats were killed and blood samples were used for analysis of hemocoagulative parameters, hemodynamics, and arterial blood gas. MAIN RESULTS: Zymosan administration caused MOFS by affecting the coagulation cascade, as shown by a significant increase in plasma levels of fibrinogen, tissue plasminogen activator, inhibitor of tissue plasminogen activator of type 1, and plasma levels of fibrin degradation products vs. control rats. Zymosan-induced MOFS was also characterized by a significant increase in von Willebrand antigen plasma levels vs. controls. Moreover, zymosan administration induced a significant fall in mean arterial blood pressure and alteration in blood gas values. HBO therapy significantly reduced the derangements of coagulation cascade, the fall in mean blood pressure and alteration in blood gas induced by zymosan administration. CONCLUSIONS: The hypercoagulability induced by zymosan could be responsible for organ failure and death. Our data demonstrate that HBO therapy significantly prevents the alteration in the coagulation cascade and arterial blood gas in an experimental model of MOFS.

The prevalence of coagulation abnormalities in hospitalized patients receiving lipid-based parenteral nutrition.

BACKGROUND: Vitamin K is not a component of the multivitamin preparation added to parenteral nutrition (PN) solutions, and hospitalized patients receiving parenteral nutrition support are at risk of developing vitamin K deficiency. METHODS: In this study, 84 consecutive patients receiving PN were followed up prospectively to determine the incidence of a raised international normalized ratio (INR). All patients received lipid in their PN, which contains approximately 30 microg of vitamin K/100 mL. RESULTS: Patients were followed up for the course of PN or up to 4 weeks if they needed longer total parenteral nutrition. A raised INR compared with baseline developed in 3.6% of patients. All elevations were mild, and no patients developed clinical bleeding. CONCLUSIONS: It may be unnecessary to routinely supplement patients with vitamin K if they are receiving a lipid emulsion containing significant amounts of vitamin K. For patients receiving warfarin therapy, it will be important for nutrition support services to be aware of the vitamin K content of the lipid emulsion they are using as patients receiving a multivitamin preparation containing vitamin K and lipid emulsion may receive increased amounts of vitamin K, which could lead to warfarin resistance.

Blood chemistry of rats pretreated with Mucuna pruriens seed aqueous extract MP101UJ after Echis carinatus venom challenge.

The effect of a lethal Echis carinatus venom on serum enzyme levels and blood plasma coagulation parameters in rats pretreated with Mucuna pruriens seed aqueous extract MP101UJ (21 mg/kg body wt) 24 h and 3 wk before i.p venom injection (0.50 mg/kg rat) and rats injected with venom alone (0.50 mg/kg body wt) was investigated. The enzyme levels and coagulation parameter levels were measured 4 h after venom administration. The results showed that the increased enzymes lactate dehydrogenase (LDH), glutamic pyruvic transaminase (SGPT), creatinine kinase (CK) and changed coagulation parameters D-Dimer and Quick levels due to the venom effect were inhibited by M. pruriens seed aqueous extract MP101UJ in pretreated rats. Rats pretreated with a single dose (21 mg/kg and multiple doses 21 mg/kg rat) of extract MP101UJ maintained the normal enzyme levels and showed an anticoagulant effect as evidenced by the high PTT level which was also observed in venom treated animals. D-Dimer and Quick values were normal. However, the extract MP101UJ appeared to significantly inhibit the lethal venom induced myotoxic, cytotoxic and coagulation activities in experimental animals.

Interaction of vitamins E and K: effect of high dietary vitamin E on phylloquinone activity in chicks.

To determine the influence of vitamin E on phylloquinone activity, one day-old chicks were raised on a masch diet supplemented with different amounts of vitamin E for 31 days. In chicks fed a diet high in vitamin E (4000 mg allrac-alpha-tocopheryl acetate/kg) but adequate in vitamin K (0.14 mg phylloquinone/kg) a threefold increase in prothrombin time and an increase in mortality rate (five out of twelve animals died from increased bleeding tendency) was observed. The inhibiting effect of high dietary vitamin E on procoagulant factors could be prevented by increasing dietary phylloquinone supplementation. Weight development, and feed utilization were insignificantly different in chicks fed different amounts and ratios of vitamins E and K1. Plasma and liver alpha-tocopherol levels correlated with dietary amounts of vitamin E. Increased phylloquinone levels in the diet did not significantly influence alpha-tocopherol concentrations in plasma and liver, but coagulopathy caused by high vitamin E intake could be reversed.

Citrate compared to low molecular weight heparin anticoagulation in chronic hemodialysis patients.

Citrate and nadroparin calcium, a low molecular weight heparin (LMWH), were compared in a randomized cross-over trial in 21 chronic hemodialysis patients regarding anticoagulation, calcium and magnesium kinetics, biocompatibility, dialysis efficiency, and aluminum contamination. Citrate was infused into the arterial line at a minimum rate of 0.68 mmol/min, combined with a calcium and magnesium-free dialysate and intravenous supplementation of calcium and magnesium at rates of 0.22 and 0.10 mmol/min, respectively. Seven patients with a dialysis session of six hours, received 2/3 of the nadroparin dose predialysis, and 1/3 after 2.5 hours (divided dose (DD) group). A single predialysis bolus injection of nadroparin was administered to eight patients not on coumarins [single dose (SD) group] and to six patients on coumarins [single dose + coumarins (SD + C) group], all with a dialysis session of four hours. Nineteen patients received a nadroparin dose of 200 ICU/kg. Two patients with a single dose, one of them on coumarins, received a dose of 150 ICU/kg because of a hematocrit < 0.30. With citrate systemic whole blood activated clotting time (ACT) remained unchanged, indicating efficient regional anticoagulation. After two hours of dialysis with nadroparin, systemic ACT increments, that is, the increase compared to predialysis, of the DD, SD, and SD + C groups were 8.8 +/- 1.5, 18.7 +/- 4.7, and 33.3 +/- 6.1 seconds, respectively (mean +/- SEM). Postdialysis ACT increments in these groups were 1.5 +/- 3.4, 17.7 +/- 6.8, and 30.3 +/- 8.0 seconds. Two hour increments of systemic activated partial thromboplastin time (APTT) of the DD, SD, and SD + C groups during nadroparin were 5.0 +/- 1.2, 15.1 +/- 2.7, and 32.2 +/- 5.5 seconds, respectively, and the corresponding postdialysis APTT increments were 2.9 +/- 1.4, 7.8 +/- 2.4, and 15.8 +/- 2.6 seconds. Two-hour anti-Xa increments of the DD, SD, and SD + C groups amounted to 0.34 +/- 0.07, 0.67 +/- 0.07, and 0.80 +/- 0.08 IU/ml. The respective postdialysis anti-Xa increments were 0.21 +/- 0.06, 0.58 +/- 0.06, and 0.71 +/- 0.08 IU/ml (All ACT, APTT and anti-Xa increments were significant; P < 0.05), except for the ACT increments and the postdialysis APTT increment of the DD group). These increments, together with unchanged prothrombin fragments 1 and 2 (PTF1 + 2), indicate systemic anticoagulation with nadroparin. The increments of serum calcium and magnesium during citrate were comparable to the increments observed with a dialysate containing 1.5 mmol/liter calcium and 0.75 mmol/liter magnesium used in combination with nadroparin. Ionized calcium increments during citrate were significant after the end of dialysis, while the dialysate containing 1.5 mmol/liter calcium induced significant increments during and postdialysis. No differences were observed between citrate and nadroparin regarding biocompatibility), (expressed as dialysis-induced leukopenia and thrombocytopenia), and dialysis efficiency [measured as dialyzer urea and creatinine clearance, normalized weekly whole body urea clearance (Kt/Vurea) and time averaged urea concentration (TACurea)]. The citrate solution, if sterilized in glass bottles, contained 2 to 3 micrograms aluminum per mmol citrate, the nadroparin solution 0.009 microgram per 1,000 ICU. Aluminum contamination of the citrate solution was prevented by sterilizing the solution in polypropylene bottles. In conclusion, citrate anticoagulation is regional and is indicated for hemodialysis patients with an active or recently active bleeding focus. However, the citrate solution should be sterilized in polypropylene containers to prevent aluminum contamination. LMWHs induce systemic anticoagulation during hemodialysis, and this effect is enhanced by concomitant coumarin use and mitigated by a divided LMWH dose regimen. For hemodialysis patients not at risk of bleeding, LMWHs provide a simple anticoagulation regimen.

Perioperative interventions to decrease transfusion of allogeneic blood products.

OBJECTIVE: To discuss some of the many options available for decreasing perioperative transfusion of allogeneic blood products. DESIGN: We review the issues that focus on the goal of developing an appropriate transfusion strategy in consideration of the individual patient's preexisting conditions, physiologic requirements, perioperative stress, and coagulation status. RESULTS: Increased awareness of transfusion-related morbidity from allogeneic blood products has resulted in increased development and application of alternatives to allogeneic transfusion. Preoperative donation and perioperative collection of autologous blood and blood products decrease exposure to allogeneic blood. Pharmacologic agents, such as antifibrinolytics, may also decrease the need for allogeneic transfusion. Perioperative use of laboratory tests of coagulation function facilitates the rapid and specific diagnosis of coagulation disorders. CONCLUSION: Physicians now have considerable appreciation of the risks and benefits of blood product transfusion. This knowledge has resulted in conservative and scientific approaches to therapy for perioperative bleeding and coagulopathy.

Recombinant lipoprotein-associated coagulation inhibitor inhibits tissue thromboplastin-induced intravascular coagulation in the rabbit.

Lipoprotein-associated coagulation inhibitor produces feed-back inhibition of tissue factor (tissue thromboplastin)-induced coagulation in the presence of factor Xa Recombinant lipoprotein-associated coagulation inhibitor (rLACI) was tested for its ability to modify thromboplastin-induced intravascular coagulation in a rabbit model that allows monitoring of iodine-125 fibrin accumulation/disappearance in the lung and sampling of blood for the measurement of coagulation parameters. Infusion of thromboplastin into the rabbit caused a rapid increase of radioactivity over the lungs, possibly due to the accumulation of 125I fibrin in the lungs, followed by a rapid decline of radioactivity, suggestive of removal of fibrin from the lungs. Thromboplastin also caused a rapid decrease of systemic fibrinogen that was accompanied by a lengthening of the activated partial thromboplastin time and prothrombin time. The effect of coinfusion of rLACI with thromboplastin or bolus injection of rLACI before thromboplastin infusion was studied. At a high dose of rLACI (800 micrograms/kg body weight), the thromboplastin-induced radioactivity increase in the lungs and the systemic fibrinogen decrease were completely suppressed. The activated partial thromboplastin time and prothrombin time of the plasma samples lengthened, possibly due to the presence of thromboplastin in circulation. The thromboplastin-induced radioactivity increase over the lungs was not completely suppressed by lower doses of rLACI (135 to 270 micrograms/kg body weight), but these doses of rLACI prevented systemic fibrinogen decrease. At a bolus dose of 23 micrograms/kg body weight, rLACI provided 50% protection of the fibrinogen consumption (fibrinogen decreased to 82% compared with 65% in rabbits treated with thromboplastin alone). These results show that rLACI is effective in the inhibition of thromboplastin-induced coagulation in vivo.

Avoiding coagulopathy in vascular surgery.

The possibility of coagulopathy can be minimized by attending to certain general perioperative details to avoid hypothermia, hypotension-shock, and multiple transfusions. In this paper, we present our protocol for avoiding coagulopathy in vascular surgery. In the past 1 1/2 years, we have used perioperative plasmapheresis in 204 patients undergoing cardiac or aortic peripheral vascular surgery. Autologous platelet-rich plasma is transfused at the completion of the operation after heparin reversal. Our data show an approximate 50% reduction in homologous blood product requirement. Seventy-five percent of patients having aortic surgery received no homologous blood products during their hospital stay. For those undergoing cardiac surgery, there has been about a 45% reduction in the use of homologous blood products. In our experience, autologous platelet-rich plasma not only decreases the risk of transmittable disease, but promotes hemostasis.

[Effect of weak alternating ultra-low frequency magnetic fields on the development of the hypercoagulation syndrome in immobilized rats]. / Vliianie slabogo peremennogo magnitnogo polia sverkhnizkoi chastoty na razvitie giperkoaguliatsionnogo sindroma pri ogranichenii podvizhnosti krys.

The experimental results are given concerning the effect of variable magnetic field (VMF) with the frequency of 8 Hz and intensity 4 A/m on some parameters of rat haemocoagulation system under standard mobile regime as well as under prolonged hypokinesia. It is stated that repeated daily exposition of VMF causes hypocoagulational blood shift in intact animals. Under the effect of simultaneous VMF and hypokinesia the correction of hypercoagulational shift induced by animal hypokinesia was detected. The highest VMF effect was observed in prolonged experiments. A conclusion is drawn concerning the ability of VMF with the given parameters to limit the development of rat blood hypercoagulation under hypokinesia.