[Evaluation of the OrthoPAT autologous transfusion system by experimental models simulating intra- and postoperative blood salvage]. / Evaluación del sistema de autotransfusión orthoPat, utilizando modelos experimentales de simulación de recuperación de sangre intra y postoperatoria.

OBJECTIVE: To evaluate the efficacy of the OrthoPAT (Haemonetics) system for blood salvage and for removing chemical or cellular debris, by experimental models simulating intra- and postoperative conditions. MATERIAL AND METHODS: Blood samples (20%-25% packed red cells) were prepared for the intraoperative model (n=8) and the postoperative model (n=22). Surgical compresses were soaked in some samples (n=5). Other samples were supplemented with hemolyzed blood (n=7). From others cytokines were removed and blood activated with bacterial liposaccharides (n=10) was added. The samples were analyzed before and after processing; tests included detection of free plasma hemoglobin (FPH), potassium ions (K+), glutamic oxalic transaminase (GOT), lactate dehydrogenase (LDH), proteins, and cytokines. RESULTS: In the intraoperative model 2935 (SD 260) mL of blood was processed. The concentration of packed red cells was 63% and 80% of the red cells were recovered. In the postoperative model 652 (35) mL was processed, the packed red cell concentration was 67% and 81% of the red cells were recovered. Reductions were observed in the concentrations of white blood cells (72%), platelets (88%), GOT and LDH (75%), and proteins and K+ (>95%). Fifty percent of the red cells were recovered in the surgical compresses model. In the hemolysis model, the K+ and FPH concentrations were reduced more than 95%. In the cytokine model, up to 90% of the interleukin 1beta, interleukin 6, and tumor necrosis factor content was removed from the activated blood samples. CONCLUSIONS: These findings suggest that the OrthoPAT system washes blood and salvages content effectively, recovering 80% of red cells. Moreover, its processing capacity (800-1000 mL x h(-1)) seems adequate for blood replacement in orthopedic surgery.

Evaluación del sistema de autotransfusión OrthoPAT®, utilizando modelos experimentales de simulación de recuperación de sangre intra y postoperatoria / Evaluation of the OrthoPAT® autologous transfusion system by experimental models simulating intra- and postoperative blood salvage

OBJETIVO: Evaluar la eficacia del sistema de autotransfusión OrthoPAT® (Haemonetics) en la recuperación de hematíes y su capacidad para eliminar contaminantes químicos o celulares, utilizando diferentes modelos experimentales de recuperación de sangre intra y post-operatoria. MATERIAL Y MÉTODOS: Se prepararon mezclas de sangre (Htc=20-25%) que fueron utilizadas en los modelos de recuperación intraoperatoria (n=8), postoperatoria (n=22), y de compresas quirúrgicas (n=5), así como en los de hemólisis (suplementadas sangre hemolizada, n=7) y eliminación de citocinas (suplementadas con sangre activada con liposacárido bacteriano, n=10). Se determinaron hematimetría, hemoglobina libre en plasma (HBLP), K+, GOT, LDH, proteínas y citocinas, antes y después del procesamiento de la sangre. RESULTADOS: En modelo intraoperatorio, se procesaron 2935±260 mL de sangre, obteniéndose un concentrado de hematíes con Htc del 63% y recuperándose el 80% de los hematíes. En el postoperatorio, estos valores fueron 652±35 mL, 67% y 81%, respectivamente, y se redujo el contenido de leucocitos (72%), plaquetas (88%), GOT y LDH (75%), proteínas y potasio (>95%). En el de compresas, se recuperó el 50% de los hematíes. En el de hemólisis, hubo una reducción >95% del contenido de K+ y HBLP. En el de citocinas, se eliminó hasta el 90% del contenido de IL-1β, IL-6 y TNFα de las mezclas suplementadas con sangre activada. CONCLUSIONES: De estos resultados parece concluirse que el sistema OrthoPAT® realiza un lavado y concentración efectivos de la sangre, recuperando el 80% de los hematíes. Además, su capacidad de procesamiento (800- 1000 mL h-1) parece ser adecuada para la reposición hemática en cirugía ortopédica

OBJECTIVE: To evaluate the efficacy of the OrthoPAT® (Haemonetics) system for blood salvage and for removing chemical or cellular debris, by experimental models simulating intra- and postoperative conditions. MATERIAL AND METHODS: Blood samples (20%-25% packed red cells) were prepared for the intraoperative model (n=8) and the postoperative model (n=22). Surgical compresses were soaked in some samples (n=5). Other samples were supplemented with hemolyzed blood (n=7). From others cytokines were removed and blood activated with bacterial liposaccharides (n=10) was added. The samples were analyzed before and after processing; tests included detection of free plasma hemoglobin (FPH), potassium ions (K+), glutamic oxalic transaminase (GOT), lactate dehydrogenase (LDH), proteins, and cytokines. RESULTS: In the intraoperative model 2935 (SD 260) mL of blood was processed. The concentration of packed red cells was 63% and 80% of the red cells were recovered. In the postoperative model 652 (35) mL was processed, the packed red cell concentration was 67% and 81% of the red cells were recovered. Reductions were observed in the concentrations of white blood cells (72%), platelets (88%), GOT and LDH(75%), and proteins and K+ (>95%). Fifty percent of the red cells were recovered in the surgical compresses model. In the hemolysis model, the K+ and FPH concentrations were reduced more than 95%. In the cytokine model, up to 90% of the interleukin 1β, interleukin 6, and tumor necrosis factor content was removed from the activated blood samples. CONCLUSIONS: These findings suggest that the OrthoPAT® system washes blood and salvages content effectively, recovering 80% of red cells. Moreover, its processing capacity (800-1000 mL·h-1) seems adequate for blood replacement in orthopedic surgery

[Ability of leukocyte reduction filters to remove fat particles from blood in experimental models simulating blood salvage in orthopedic surgery]. / Capacidad de los filtros leucorreductores para la eliminación de partículas de grasa en sangre. Modelo experimental de simulación de la sangre recuperada en cirugía ortopédica.

BACKGROUND: Salvaged autologous blood in orthopedic surgery may contain tissular debris such as fat particles (FP), possibly increasing the risk of fat embolism after bone surgery. Therefore, this study was initiated to ascertain the capacity of leukocyte filters to remove FP using in vitro models. METHODS: All experiments were performed in triplicate using donor blood bags within 15 days of their donation. Five different olive oil volumes were added to blood to obtain 5 oil concentrations (1% to 5%), and blood was subsequently filtered through a PureCell (Pall Biomedical, Portsmouth, UK) leukocyte-reduction filter. In another set of experiments, 5 different oil volumes (1, 2.5, 5, 7.5 or 10 mL) were injected into the line during filtration of oil-free blood. In addition, 3 preparations of blood supplemented with 5% oil were processed in the autotransfusion device OrthoPAT (Haemonetics Corp, Braintree, MA, USA), and the obtained red cell concentrate was subsequently filtered through PureCell. We collected samples for cell counting and analysis and FP detection with a Pentra 120 Retic (ABX, Montpellier, France) flow cytometer. RESULTS: Specific signals corresponding to FP were clearly detected in the white blood cell scattergrams yielded by the cytometer for oil supplemented blood. PureCell removed FP up to an oil concentration of 3% or up to an injected oil volume of less than 10 mL. Addition of a filtration step through a PureCell filter after blood washing by the OrthoPAT device completely removed FP. CONCLUSIONS: Leukocyte filters seem to be useful for removing FP from unprocessed blood with a low degree of fat contamination (less than 10 mL) and to complete FP removal from processed blood. Therefore, using a leukocyte filter in the patient's line should contribute to improving the safety of perioperative autologous blood salvage.

Capacidad de los filtros leucorreductores para la eliminación de partículas de grasa en sangre. Modelo experimental de simulación de la sangre recuperada en cirugía ortopédica / Ability of leukocyte reduction filters to remove fat particles from blood in experimental models simulating blood salvage in orthopedic surgery

OBJETIVOS: La sangre autóloga recuperada en cirugía ortopédica puede contener detritus tisulares, como partículas grasas (PG),con riesgo de embolismo graso. Se ha estudiado la capacidad de los filtros de leucocitos en la eliminación de PG, utilizando diferentes modelos in vitro . MÉTODOS: Todos los ensayos se realizaron por triplicado utilizando bolsas de sangre con menos de 15 días de almacenamiento. Se añadieron diferentes volúmenes de aceite de oliva a la sangre, para obtener 5 concentraciones de aceite (1 a 5%),siendo posteriormente filtrada a través del filtro de leucocitos PureCell (Pall). En otra serie de experimentos, se inyectaron diferentes volúmenes de aceite (1;2,5;5;7,5 ó 10 ml)en el circuito durante la filtración de sangre sin grasa. Además, se procesaron 3 preparaciones de sangre con aceite al 5% en el autotransfusor OrthoPAT (Haemonetics)y el con- centrado de hematíes obtenido se filtró a través de PureCell.Se tomaron muestras para hematimetría y detección de PG (analizador Pentra 120 Retic,ABX). RESULTADOS: En los diagramas de dispersión de leucocitos obtenidos para la sangre que contenía aceite, se detectaron claramente las señales específicas correspondientes a PG. El filtro PureCell eliminó las PG hasta una concentración de aceite del 3%o hasta un volumen de aceite inyectado en el circuito inferior a 10 ml. Además, PureCell eliminó totalmente las PG remanentes en sangre procesada por OrthoPAT. CONCLUSIONES: Los filtros de leucocitos parecen ser útiles para eliminar las PG de sangre no procesa- da con bajo grado de contaminación grasa (inferior a 10 mL),y para completar la eliminación de PG en sangre procesada. Por tanto, su uso en la línea de infusión al paciente podría contribuir a aumentar la seguridad de la recuperación perioperatoria de sangre autóloga

BACKGROUND: Salvaged autologous blood in ortho- pedic surgery may contain tissular debris such as fat par- ticles (FP), possibly increasing the risk of fat embolism after bone surgery. Therefore, this study was initiated to ascertain the capacity of leukocyte filters to remove FP using in vitro models. METHODS: All experiments were performed in triplicate using donor blood bags within 15 days of their donation. Five different olive oil volumes were added to blood to obtain 5 oil concentrations (1%to 5%),and blood was subsequently filtered through a PureCell (Pall Biomedical,Portsmouth,UK)leukocyte-reduction filter. In another set of experiments,5 different oil volumes (1, 2.5,5,7.5 or 10 mL)were injected into the line during filtration of oil-free blood.In addition,3 preparations of blood supplemented with 5%oil were processed in the autotransfusion device OrthoPAT (Haemonetics Corp, Braintree, MA, USA),and the obtained red cell concentrate was subsequently filtered through PureCell. We collected samples for cell counting and analysis and FP detection with a Pentra 120 Retic (ABX, Montpellier, France)flow cytometer. RESULTS: Specific signals corresponding to FP were cle- arly detected in the white blood cell scattergrams yielded by the cytometer for oil supplemented blood. PureCell removed FP up to an oil concentration of 3%or up to an injected oil volume of less than 10 mL. Addition of a filtration step through a PureCell filter after blood washing by the OrthoPAT device completely removed FP. CONCLUSIONS: Leukocyte filters seem to be useful for removing FP from unprocessed blood with a low degree of fat contamination (less than 10 mL)and to complete FP removal from processed blood. Therefore, using a leukocyte filter in the patient ’s line should contribute to improving the safety of perioperative autologous blood salvage

Both alleles of the M235T polymorphism of the angiotensinogen gene can be a risk factor for myocardial infarction.

We have studied the role of three polymorphic genes of the renin-angiotensin system (RAS) as independent risk factors for myocardial infarction (MI) and their correlation with three of the major coronary risk factors: serum cholesterol (CH), hypertension (HT) and smoking (SM). A population of 392 men was genotyped for the M235T polymorphism of the angiotensinogen (AGT) gene, the insertion/deletion of the angiotensin-converting enzyme (ACE) and the all66c of the angiotensin-II type 1 receptor (AT1R), by means of polymerase chain reaction (PCR) and restriction enzyme analysis. It was observed that the T allele frequency increased significantly in the MI with HT, CH, and SM subgroup (0.58 vs 0.31) (p<0.01). In contrast, the M allele frequency was higher in the MI without HT, CH, and SM (0.69 vs 0.42) (p<0.01). A strong association between the MM genotype and MI (p<0.001, odds ratio=4.29, confidence interval=1.95-9.42) was found when age-matched MM control subjects were compared to MI individuals with none of the other known major coronary risk factors. Futhermore, subjects with the MM genotype showed a significantly higher plasma renin activity (PRA) profile than those with the TT genotype (p<0.001). It can be concluded that the M allele is an independent risk factor for MI and the T allele modified the risk when other major risk factors are present.

The genotype interactions of methylenetetrahydrofolate reductase and renin-angiotensin system genes are associated with myocardial infarction.

We analyzed the evolution with age of the frequencies of the I/D polymorphism of the angiotensin I-converting enzyme (ACE), a1166c of the angiotensin II AT1 receptor (AT1R), M235T of the angiotensinogen (AGT) and A225V of their methylenetetrahydrofolate reductase (MTHFR) gene in a healthy (H) population and the subsequent comparison to age- and sex-matched groups of myocardial infarction (MI) subjects. A total of 472 H subjects were divided into three groups < 30, 30-55 and > 55 years old and 277 individuals with MI into two groups 30-55 and > 55 years old. The evolution with age showed that the AGT M allele (P < 0.001) and the MTHFR V allele (P < 0.05) frequency decreased with age in H men. The comparison between healthy and MI groups showed that the MM genotype frequency increased in MI men > 55 years (OR =4.16; 95% CI; 1.72-10.1) The cc genotype showed a similar behaviour (OR = 3.96; 95% CI; 1.21-12.9). In men, all the combinations with MM genotype presented a high risk, with OR values between 1.10 and 7.22. In women, the cc genotype increased in the MI > 55 group (OR = 6.66; 95% CI; 2.02-21.9). All the combinations with the cc genotype showed OR values between 1.71 and 13.3. The MM genotype in men and cc genotype in men and women, are independent risk factors for MI. We propose that the study of the allele frequency evolution in an H population at different ages is essential to determine risk factors for MI in case-control studies, since data from isolated age-matched groups can be misinterpreted.