The Safety and Short-term Outcomes of Leukocyte Depleted Autologous Transfusions During Radical Cystectomy.

OBJECTIVE: To examine long- and short-term outcomes using cell salvage with a commercially available leukocyte depletion filter following radical cystectomy in an oncologic population. MATERIALS AND METHODS: One hundred and fifty-seven patients, 87 of whom received a cell salvage transfusion, were retrospectively identified from chart review. Ninety-day outcomes as well as long-term mortality and cancer recurrence data were collected. Chi-square, Student's t, or Mann-Whitney U tests were used as appropriate. Multivariable regressions of survival were performed with a Cox proportional-hazards model. RESULTS: Those who received a cell salvage transfusion did not show any differences in rate of cancer recurrence (23%) vs those who did not receive a cell salvage transfusion (24%; P = .85). There were also no differences noted in mortality rates between the 2 populations (12% vs 17%; P = .36). Furthermore, no differences were noted in postoperative complication rates, length of hospital stay, 90-day culture positive infections or readmissions (P >.05). CONCLUSION: There are no significant differences in short-term or long-term patient outcomes between those who did and did not receive an intraoperative cell salvage transfusion. Cell salvage transfusions with a leukocyte depletion filter are safe and effective methods to reduce the need for allogeneic blood transfusions while controlling for the theoretical risk of metastatic spread.

A Novel Centrifugation Method Using a Cell Salvage Device Offers an Alternative to the Use of Leukocyte-Depleting Filters for Autologous Blood Transfusions.

Autotransfusion protocols often use the use of costly filters, such as leukocyte-depleting filters (LDFs), to minimize reinfusion of activated leukocytes and inflammatory mediators associated with reperfusion injury (RI). LDFs are used extensively in hospital settings; however, they represent an additional capital expenditure for hospitals, as well as a constraint on the reinfusion rate of blood products for health-care providers. We compared a commonly used LDF to a novel centrifugation method employing a widely used cell salvage device. Complete blood counts and enzyme-linked immunosorbent assays (ELISAs) measuring tumor necrosis factor-α (TNF-α) and interleukin-2 (IL-2) were performed to compare the efficacy of these methodologies. The LDF removed, on average, 94% of all leukocytes, including 96% of neutrophils. The centrifugation method removed, on average, 89% of all leukocytes, including 91% of neutrophils and resulted in a highly concentrated red blood cell product. Our results suggest both methods offer equivalent leukocyte reduction. TNF-α was also comparably reduced following our novel centrifugation method and the LDF method and IL-2 levels were undetectable in all samples. These results indicate our novel centrifugation method may preclude the need for a LDF during select autotransfusion applications.

Efficacy of the RemoweLL cardiotomy reservoir for fat and leucocyte removal from shed mediastinal blood: a randomized controlled trial.

INTRODUCTION: Re-transfusion of lipid particles and activated leucocytes with shed mediastinal blood (SMB) can aggravate cardiopulmonary bypass-associated inflammation and increase the embolic load. This study evaluated the fat and leucocyte removal capacity of the RemoweLL cardiotomy reservoir. METHODS: Forty-five patients undergoing elective on-pump cardiac surgery were randomly allocated to filtration of SMB using the RemoweLL or the Admiral cardiotomy reservoir. The primary outcome was a drop in leucocytes and lipid particles obtained with the two filters. The effect of the filters on other blood cells and inflammatory mediators, such as myeloperoxidase (MPO), was also assessed. RESULTS: The RemoweLL cardiotomy filter removed 16.5% of the leucocytes (p<0.001) while no significant removal of leucocytes was observed with the Admiral (p=0.48). The percentage reductions in lipid particles were similar in the two groups (26% vs 23%, p=0.2). Both filters similarly affected the level of MPO (p=0.71). CONCLUSION: The RemoweLL filter more effectively removed leucocytes from SMB than the Admiral. It offered no advantage in terms of lipid particle clearance.

A laboratory study of the effects of processing blood through a cell salvage device and leucocyte depletion filter on levels of pro-inflammatory cytokines and bradykinin.

We investigated changes in concentrations of interleukin-1ß, interleukin-6, tumour necrosis factor-α and bradykinin in blood during passage through a cell salvage device and a leucocyte depletion filter, with or without application of subatmospheric pressure across the filter. Blood samples from 19 healthy women undergoing scheduled caesarean section showed concentrations of cytokines and bradykinin in blood filtered under gravity flow that were equal to or significantly lower than those of pre-operative venous blood samples. They were also significantly lower than that in postoperative orthopaedic shed blood, which is commonly reinfused after orthopaedic surgery. A minority of samples taken from blood that had been filtered using subatmospheric pressure showed raised interleukin-6 concentrations. We suggest that use of a leucocyte depletion filter for cell-salvaged blood with gravity flow is likely to be safe with regard to concentrations of cytokines and bradykinin. However, this may not hold true for the filter used with subatmospheric pressure. If transfusion of salvaged blood using a leucocyte depletion filter seems to induce hypotension, elevation of interleukin-6 should be suspected.

Acute hypotension associated with intraoperative cell salvage using a leukocyte depletion filter during management of obstetric hemorrhage due to amniotic fluid embolism.

Amniotic fluid embolism (AFE) is a rare but catastrophic obstetric complication that can lead to profound coagulopathy and hemorrhage. The role of cell salvage and recombinant human Factor VIIa (rFVIIa) administration in such cases remains unclear. We present a case of AFE and describe our experience with the use of cell salvage and rFVIIa administration during the resuscitation. Cell salvage and transfusion through a leukocyte depletion filter was attempted after the diagnosis of AFE was made, but the attempted transfusion was immediately followed by hypotension and a worsening of hemodynamics. rFVIIa, on the contrary, was used with clinical improvement in coagulopathy and without apparent adverse thrombotic effect.

Use of a leucocyte filter to remove tumour cells from intra-operative cell salvage blood.

SUMMARY: The intra-operative blood loss of 50 consecutive gynae-oncology patients undergoing surgery for endometrial, cervical or ovarian cancer was cell salvaged and filtered. In each case blood samples were taken from the effluent tumour vein, a central venous line, the cell saver reservoir, the cell salvage re-transfusion bag after processing but before filtration and from the cell salvage re-transfusion bag after processing and filtration. Samples were examined using immunohistochemical monoclonal antibody markers for epithelial cell lines. Viable, nucleated malignant cells were detected in 2/50 central venous samples, 34/50 reservoir samples and 31/50 unfiltered cell salvaged samples. After passage through a Pall RS leucocyte depletion filter no remaining viable, nucleated malignant cells were detected in any sample. The clinical risks of cell salvage in these circumstances should be reviewed in the light of the risks of allogeneic blood transfusion.

Leukocyte removal efficiency of cell-washed and unwashed whole blood: an in vitro study.

Leukocyte filtration of the cardiopulmonary bypass (CPB) perfusate after cardiac surgery has evolved as an important technique to prevent effector functions mediated by activated leukocytes. However, little is known about the filtration efficiency. Therefore, an in vitro study was conducted to define the leukocyte removal rate of a transfusion leukocyte-depletion filter, using cell-washed and unwashed whole porcine blood. In addition, the influence of different cell-washing protocols on the elimination rate of blood cells (leukocytes and platelets) was investigated. Fresh, diluted, pooled, heparinized, porcine blood was processed using either a high-flow (HF, n = 5) or quality-wash (QW, n = 5) protocol on a continuous auto-transfusion system, or was left unprocessed (control n=5). Thereafter, all samples were filtered using a transfusion leukocyte-depletion filter. Blood samples for measurement of hematocrit, white blood cell count, including leukocyte differentiation and platelet count, were taken before and after filtration. To compare the experimental groups, the removal rate was presented as the fraction of leukocytes or platelets removed per plasma volume. Cell washing significantly altered the fraction of leukocytes removed per plasma volume when compared to unprocessed blood (2.07 and 2.36 in the HF and QW groups, respectively, versus 1.34 in the control group, p = 0.008 for both). No statistically significant difference in leukocyte removal rate was observed between the different cell-washing protocols. The leukocyte differential count showed that, during all experiments, the neutrophils were removed most efficiently (99.7%). Overall, significantly more platelets were depleted after cell washing compared to the control group (1.47 and 1.60 in the HF and QW groups, respectively, versus 1.12 in the control group, p =0.008 and 0.032, respectively). Furthermore, the amount of blood that could be filtered using a single pass technique did not significantly differ between the experimental groups. However, a larger variation in the total amount of filtered blood was observed in the unprocessed group (570+/-398 mL) compared to the cell-washed groups (360+/-42 and 430+/-97 mL in the HF and QW groups, respectively). In conclusion, blood processing with an auto-transfusion system significantly enhances the leukocyte and platelet removal efficiency of the transfusion leukocyte-depletion filter that was studied. In particular, neutrophils were efficiently removed.

[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.