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PubMed2005

Do blood tests cause anemia in hospitalized patients? The effect of diagnostic phlebotomy on hemoglobin and hematocrit levels.

OBJECTIVE: To determine whether phlebotomy contributes to changes in hemoglobin and hematocrit levels in hospitalized general internal medicine patients. DESIGN: Retrospective cohort study. SETTING: General internal medicine inpatient service at a tertiary care hospital. PARTICIPANTS: All adult patients discharged from the Toronto General Hospital's internal medicine service between January 1 and June 30, 2001. A total of 989 hospitalizations were reviewed and 404 hospitalizations were included in our analysis. MEASUREMENTS AND MAIN RESULTS: Mean (SD) hemoglobin and hematocrit changes during hospitalization were 7.9 (12.6) g/L (P<.0001) and 2.1% (3.8%) (P<.0001), respectively. The mean (SD) volume of phlebotomy during hospital stay was 74.6 (52.1) mL. On univariate analysis, changes in hemoglobin and hematocrit were predicted by the volume of phlebotomy, length of hospital stay, admission hemoglobin/hematocrit value, age, Charlson comorbidity index, and admission intravascular volume status. The volume of phlebotomy remained a strong predictor of drop in hemoglobin and hematocrit after adjusting for other predictors using multivariate analysis (P<.0001). On average, every 100 mL of phlebotomy was associated with a decrease in hemoglobin and hematocrit of 7.0 g/L and 1.9%, respectively. CONCLUSIONS: Phlebotomy is highly associated with changes in hemoglobin and hematocrit levels for patients admitted to an internal medicine service and can contribute to anemia. This anemia, in turn, may have significant consequences, especially for patients with cardiorespiratory diseases. Knowing the expected changes in hemoglobin and hematocrit due to diagnostic phlebotomy will help guide when to investigate anemia in hospitalized patients.

Aged↗
PubMed2002

Long term effects of phlebotomy on biochemical and histological parameters of chronic hepatitis C.

OBJECTIVES: There is considerable evidence that iron is a risk factor for liver injury in chronic hepatitis C. Known as iron reduction therapy, phlebotomy reduces serum ALT activity. This effect might continue with maintenance phlebotomy and result in slower progression of liver fibrosis. METHODS: We examined the biochemical parameters and liver histology of patients with chronic hepatitis C treated by maintenance phlebotomy. For biochemical evaluation, 25 patients were treated by initial phlebotomy to reduce serum ferritin levels to 10 ng/ml or less and then observed for 5 yr with maintenance phlebotomy to maintain the iron-deficient state. For histological evaluation, liver biopsies were performed before and after the study period in 13 of the patients. Thirteen patients who were virological nonresponders to interferon alone and had undergone second liver biopsies after more than 3 yr served as histological controls. RESULTS: Serum aminotransferase levels were decreased significantly by initial phlebotomy and remained at the same levels during the study period (p < 0.05). The grading scores were improved significantly in the study group (p < 0.05) and unchanged in the controls. The staging scores remained unchanged in the study group but were increased in the controls (p < 0.005). Disease progression was significantly different between the two groups (p < 0.05). CONCLUSIONS: These results suggest that phlebotomy with maintenance lowers serum aminotransferase levels, improves liver inflammation, and suppresses the progression of liver fibrosis in chronic hepatitis C.

Adult↗
PubMed2006

Highly conservative phlebotomy in adult intensive care--a prospective randomized controlled trial.

Anaemia in critically ill patients is common and phlebotomy associated blood loss may contribute towards this anaemia. The aims of this study were twofold. Firstly, a survey was conducted to provide a summary of current phlebotomy practices within Australian intensive care units. A standardized telephone survey was aimed at Australian intensive care units registered with Australia and New Zealand Intensive Care Society (ANZICS) and questions regarding phlebotomy procedures directed at nursing staff. Secondly, a prospective randomized controlled trial aimed to assess the impact of a highly conservative phlebotomy procedure on haemoglobin concentration in intensive care patients. Patients admitted to our own intensive care unit were randomized using a sealed envelope technique to either a highly conservative phlebotomy group, or standardized controls. Blood was taken according to strict protocols and recorded along with haemoglobin concentration daily. The survey demonstrated that 16% of Australian units return deadspace volumes from in-line arterial sets and no unit routinely used paediatric-sized blood collection tubes. Using our highly conservative protocol, median phlebotomy-associated blood loss was reduced by over 80% (40 ml vs 8 ml P<0.001). Mean haemoglobin fell from 13.7 g/dl to 11.7 g/dl in controls (P=0.002) and from 12.7 g/dl to 11.5 g/dl (P=0.074) in our study group. We conclude that highly conservative phlebotomy is feasible in a critical care unit and is associated with a reduction in blood loss.

APACHE↗
PubMed2003

[Protective effects of preconditioning phlebotomy against myocardial ischemia-reperfusion injury in rat].

OBJECTIVE: To investigate the protective effect of preconditioning phlebotomy against ischemia-reperfusion injury and the role of calcitonin gene-related peptide (CGRP) in this protection mechanism. METHODS: Sixty SD rats were randomly assigned in equal number into control, phlebotomy, and CGRP polyclonal antibody (PcAb) groups, all of which were subjected to 30 min regional ischemic followed by two-hour reperfusion, initiated 15 min after phlebotomy in the latter 2 groups. The rats in CGRP PcAb group were given the antibody (2.5 mg/kg) before phlebotomy. After the operations, plasma CGRP level was determined in 8 rats from each group by radioimmunoassay, and the infarct size (IS) by nitro blue tetrazolium, represented as percentage of the area at risk (AAR). RESULTS: The mean plasma CGRP level was significantly increased in phlebotomy group compared with the levels in control and PcAb groups (F=12.4, P=0.032-0.005), and a significant reduction in IS (F=52.4, P<0.001) and IS/AAR (F=43.7, P<0.001) occurred in phlebotomy group. CONCLUSION: Preconditioning phlebotomy has obvious cardioprotective effect against ischemia-reperfusion injury, in the mechanism of which CGRP may play a role.

Animals↗
PubMedDate not supplied

Additional effect of low iron diet on iron reduction therapy by phlebotomy for chronic hepatitis C.

BACKGROUND/AIMS: Iron-induced oxidative stress plays an important role in the pathogenesis of chronic hepatitis C. Both phlebotomy for removing body iron stores and low iron diet for minimizing portal iron supply to the liver have been shown to improve serum transaminase levels in patients with the disease. However, the cooperative effects of phlebotomy and low iron diet have not yet been elucidated in detail. METHODOLOGY: A pilot study was undertaken to investigate whether a low iron diet could improve the efficacy of phlebotomy in iron reduction therapy. Of 21 patients diagnosed with chronic hepatitis C, 10 patients were treated with phlebotomy alone (group A) while 11 patients were treated with a low iron plus phlebotomy (group B). Phlebotomy was repeated biweekly until serum ferritin levels reached 10 ng/mL in both A and B groups. In addition, a low iron diet (iron intake of 8 mg/day or less) was recommended for group B, followed by estimation of iron intake from daily diet records. RESULTS: Serum alanine aminotransferase levels were significantly improved from 106+/-30 to 68+/-22 IU/L (p<0.005, paired t-test) in group A and from 100+/-33 to 46+/-10 IU/L (p<0.002, paired t-test) in group B. The enzyme levels after treatment were significantly higher in group A (p<0.02, non-paired t-test), which showed a higher upward distribution of the enzyme activity. The estimated dietary iron intake in group B was reduced from 17.6+/-6.1 to 8.2+/-3.7 mg/day. CONCLUSIONS: These findings suggest that phlebotomy alone does not completely remove iron-induced oxidative stress and a low iron diet induces an additional effect in iron reduction therapy for chronic hepatitis C.

Adult↗
PubMed2006

Evaluation of arterial compliance in polycythemia vera patients: short and long-term influence of phlebotomy.

BACKGROUND: Thrombosis is a major cause of morbidity and mortality in polycythemia vera. Hypercoagulability is principally due to hyperviscosity of the whole blood, an exponential function of the hematocrit. PV is also associated with endothelial dysfunction that can predispose to arterial disease. Reduction of the red cell mass to a safe level by phlebotomy is the first principle of therapy in PV. This therapy may have some effect on the arterial compliance in PV patients. OBJECTIVES: To estimate the influence of phlebotomies on large artery (Cl) and small artery compliance (C2) in PV patients by using non-invasive methods. METHODS: Short-term hemodynamic effects of phlebotomy were studied by pulse wave analysis using the HDI-Pulse Wave CR2000 (Minneapolis, MN, USA) before and immediately after venesection (350-500 ml of blood). We repeated the evaluation after 1 month to measure the long-term effects. RESULTS: Seventeen PV patients were included in the study and 47 measurements of arterial compliance were performed: 37 for short-term effects and 10 for long-term effects. The mean large artery compliance (C1) before phlebotomy was 12.0 ml/mmHg x 10 (range 4.5-28.6), and 12.6 ml/mmHg x 10 (range 5.2-20.1) immediately after phlebotomy (NS). The mean small artery compliance (C2) before and immediately after phlebotomy were 4.4 mg/mmHg x 10 (range 1.2-14.3) and 5.5 mg/mmHg x 10 (range 1.2-15.6) respectively (delta C2-1.1, P < 0.001). No difference in these parameters could be demonstrated in the long-term arm. CONCLUSIONS: Phlebotomy immediately improves arterial compliance in small vessels of PV patients, but this effect is short lived.

Aged↗
PubMed2004

Pharmacokinetic tracer kinetics analysis of changes in erythropoietin receptor population in phlebotomy-induced anemia and bone marrow ablation.

OBJECTIVES: The objective was to study in vivo erythropoietin (Epo) progenitor cell surface receptors (EpoR) in the bone marrow (BM) after phlebotomy and bone marrow ablation. METHODS: Serial tracer interaction method experiments were conducted in adult sheep at baseline and after phlebotomy (PH) and ablation (AB). PH was done 10 days after phlebotomy (to 3-4 g/dl Hb), and the AB was done 8 days after a 3-day oral treatment with bulsulfan (11 mg/kg/day). RESULTS: Bone marrow ablation changed the elimination from non-linear to linear, consistent with an abolition of the non-linear elimination via BM EpoRs. The phlebotomy increased the linear clearance of the ablated elimination pathway (from 63.6+/-12 to 126+/-64 ml/h/kg), consistent with an up-regulation of the erythroid progenitor BM-based EpoR pool, but did not change the clearance of the non-ablated elimination pathway (p>0.05). The EpoR pool size remaining after BM ablation was 7.4+/-2.7% of the pre-ablation pool. CONCLUSIONS: Erythropoietin elimination via EpoR in the bone marrow was non-linear and increased following phlebotomy-induced anemia. This is consistent with an up-regulation of the erythropoietic EpoR pool in BM. Assuming that the elimination of Epo after BM ablation was via non-hematopoietic EpoR, then this post-ablation EpoR population was not significantly up-regulated by the phlebotomy.

Alkylating Agents↗
PubMed2005

Soluble transferrin receptor in hemochromatosis patients during phlebotomy therapy.

BACKGROUND: The monitoring of phlebotomies in hemochromatosis patients depends on iron status measured by ferritin and transferrin saturation (TS). However, in the presence of inflammation or liver injury, soluble transferrin receptor (sTfR) determination was proposed to replace ferritin for diagnosing iron deficiency (ID). The present study evaluated performances of sTfR for the prediction of iron deficiency in a large number of hemochromatosis patients under phlebotomy therapy. METHODS: We studied 52 patients undergoing therapeutic phlebotomies and obtained 2 samples from 37 patients. Biological parameters were determined before each phlebotomy began. Performances of sTfR and TS in the diagnosis of iron deficiency were compared, according to ferritin levels under 12 microg/l. RESULTS: Ferritin and TS were correlated with removed iron (r=0.473, p<0.005 and r=0.345, p<0.05, respectively) and sTfR was correlated with the decrease in hemoglobin levels induced by phlebotomies (r=-0.678, p<0.0001). Areas under Receiver Operating Characteristics (ROC) curves for sTfR and TS were not statistically different for prediction of iron deficiency and sensitivity/specificity of sTfR at 1.64 mg/l were 67/86%. CONCLUSIONS: sTfR determination could be used to predict iron depletion induced by phlebotomies when ferritin is of limited interest, to avoid the appearance of anemia.

Adult↗
PubMed2000

[Prevention of sickle cell crises with multiple phlebotomies].

OBJECTIVES: Sickle cell disease patients suffering from frequent painful crises were submitted to phlebotomies in order to reduce hospitalization days due to pain, through hemoglobin (Hb) level reduction and iron deficiency in patients with an hemoglobin level equal to or above 9.5 g/dL. PATIENTS: Seven sickle cell disease patients (four SC, three SS), aged four to 24 years, were submitted to sequential phlebotomies during periods from 18 months to four years. METHODS: The number of hospitalization days for crises was considered. The volumes and frequencies of phlebotomies were adjusted according to the patients ages, the hemoglobin concentrations and the serum ferritin levels. RESULTS: One hundred and forty-four hospitalization days were recorded in the seven patients in the year preceding the treatment. During the study period, the annual numbers of hospitalization days were respectively 20, five, six and one. Mean hemoglobin concentration was 10.7 g/dL before phlebotomies and 8.8 to 9.2 g/dL during the four years of treatment. Mean corpuscular volume, mean corpuscular hemoglobin concentration and serum ferritin were also reduced. The volume of phlebotomies was 116 to 39 mL/kg/year according to the patients. COMMENTS AND CONCLUSION: The striking decrease of the number of hospitalization days for all the patients suggests a closed relationship between therapy and clinical improvement. The mechanism of this effect is probably multifactorial: a) the concentration of Hb level is known to influence the blood viscosity and its decrease always improved rheology in sickle cell disease patients; b) the mean corpuscular hemoglobin concentration is a critical factor concerning the HbS molecule polymerization in sickle cell disease, and its slight reduction may have an important biological effect. We observed these two biological modifications in our patients and suggest that they mediate the clinical effects. The iron deficiency induced by phlebotomies has no evident deleterious consequence either on height and weight in the children or on intellectual performance in any patients.

Adolescent↗
PubMed1998

Effect of enalapril on exaggerated erythropoietin response to phlebotomy in erythrocytosic renal transplant patients.

BACKGROUND: Exaggerated erythropoietin (EPO) response to phlebotomy regardless of the baseline EPO levels have been shown in patients with post-transplant erythrocytosis (PTE) and administration of angiotensin-converting enzyme inhibitors (ACE-1) seems to be effective in controlling PTE. However, the mechanism of this ACE-1 induced reduction in haematocrit (Hct) is not well known. Although some authors have suggested that ACE-1 may reduce EPO secretion, this is still controversial. The aim of the present study was to assess the effect of a single dose ACE-1 on exaggerated EPO response to phlebotomy. METHODS: In this study, we compared serum EPO and renin (PRA) levels of 10 PTE patients, 10 non-PTE patients and 10 healthy blood donors before and after phlebotomy. The effects of a single dose of ACE-1 (enalapril, 5 mg p.o.) in PTE patients were also evaluated in the second phlebotomy. RESULTS: While the mean basal serum EPO level was significantly higher in the PTE group than the other two groups (P<0.01), the mean basal PRA levels did not differ significantly between these groups. Serum EPO and PRA levels increased significantly after the phlebotomy (P<0.001) and exaggerated EPO response to phlebotomy was suppressed by single dose enalapril (P<0.001) in the PTE patients. CONCLUSION: The present study has shown that the renin angiotensin system plays an important role in EPO formation and the Hct lowering effect of the ACE-1 is through reduction of EPO in PTE patients.

Adult↗
PubMed1998

Hepatic iron concentration in hereditary hemochromatosis does not saturate or accurately predict phlebotomy requirements.

OBJECTIVE: Biochemical measurement of the hepatic iron concentration (HIC) is essential for the diagnosis of hereditary hemochromatosis (HH). The aim of this study was to determine whether the HIC at the time of diagnosis could predict the subsequent phlebotomy requirements and to determine whether saturation of HIC occurred in HH. METHODS: Fifty-four patients (32 male, 22 female) with homozygous HH were evaluated, and HIC was measured in liver biopsies. Patients were subjected to weekly phlebotomy (500 ml) until the transferrin saturation was <50% and/or the serum ferritin concentration was <50 microg/L. The relationship between HIC and total body iron stores (as measured by phlebotomy requirements) was determined using both linear and nonlinear (sigmoidal model) least squares regression. RESULTS: The HIC ranged from 3,742 to 41,040 microg/g dry wt. A linear relationship between HIC and total body iron stores (iron removed, IR, g) best described the data both in male (HIC = 1986 IR - 3494; r = 0.83; p < 0.001) and female HH patients (HIC = 1251 IR + 2690; r = 0.75; p < 0.001). Men required eight more phlebotomies (2 g iron) on average, compared with women, to reach normal iron stores. There was no evidence of saturation of hepatic iron levels at higher total body iron stores. However, accurate prediction of individual phlebotomy requirements based on the HIC or serum ferritin concentration at the time of diagnosis was not possible. CONCLUSION: The phlebotomy requirement for treatment of HH cannot be accurately predicted from the initial HIC or serum ferritin level. Within the range examined, hepatic iron deposition did not saturate in HH.

Adult↗
PubMed2002

Outpatient phlebotomy success and reasons for specimen rejection.

OBJECTIVES: To determine the rate with which blood collection is successful on the initial phlebotomy encounter, the rate with which laboratory personnel judge specimens unsuitable for analysis, and the practice characteristics associated with fewer unsuccessful collections and fewer rejected specimens. DESIGN: Clinical laboratories participating in the College of American Pathologists Q-Probes laboratory improvement program prospectively characterized the outcome of outpatient phlebotomies for 3 months or until 20 unsuccessful phlebotomy encounters occurred. By questionnaire, participants provided information about test ordering, patient preparation, and specimen collection. SETTING AND PARTICIPANTS: Institutions in the United States (n = 202), Canada (n = 4), Australia (n = 3), and South Korea (n = 1). MAIN OUTCOME MEASURES: Percentage of successful encounters and percentage of unsuitable specimens. RESULTS: Of 833289 encounters, 829723 were successful. Phlebotomies were unsuccessful because patients were not fasting as directed (32.2%), phlebotomy orders were missing information (22.5%), patients specimens were difficult to draw (13.0%), patients left the collection area before specimens were collected (11.8%), patients were improperly prepared for reasons other than fasting (6.3%), patients presented at the wrong time (3.1%), or for other reasons (11.8%). Only 2153 specimens (0.3%) were unsuitable; these samples were hemolyzed (18.1%), of insufficient quantity (16.0%), clotted (13.4%), lost or not received in the laboratory (11.5%), inadequately labeled (5.8%), at variance with previous or expected results (4.8%), or unacceptable for other reasons (31.1%). Facilities staffed by laboratory-administered phlebotomists reported higher success rates than facilities staffed by nonlaboratory-administered phlebotomists (P =.002). CONCLUSIONS: Most outpatient phlebotomy encounters are successful and result in specimens suitable for laboratory analysis.

Australia↗
PubMed2000

Phlebotomy skills expected of career entry CLS/CLT graduates: a Missouri hospital perspective.

OBJECTIVE: To determine how much, what type, and what proficiency of phlebotomy experience CLS/CLT students should have during the training program to be prepared to meet the needs of the majority of Missouri hospital employers. DESIGN: Survey to determine the role healthcare professionals, inside and outside the laboratory, play in today's blood collection patterns and phlebotomy management. SETTING/PARTICIPANTS: The Missouri Organization of Clinical Laboratory Science mailed 204 surveys to the Missouri Hospital Association member laboratories. MAIN OUTCOMES/CONCLUSIONS: This research examined the need for modifying phlebotomy skills of clinical laboratory science students. Data gathered from employers support the premise that entry-level competencies of CLS/CLT graduates will vary according to clinical facility size. CLS/CLT programs may use data from this study to plan phlebotomy practicums. It can be extrapolated that Missouri employers who are most likely to employ career entry graduates expect them to draw blood from 9.3 patients within one hour. Fifty-three percent of 40 to 400 bed hospitals expect graduates to perform difficult draws in at least eight types of hospital units. Laboratories are the major managers of hospital wide phlebotomy services; thus, CLS/CLT curricula should include phlebotomy management methods.

Curriculum↗
PubMed1991

Physiological response to phlebotomies for autologous transfusion at elective hip-joint surgery.

In order to study the physiological response to phlebotomies for autotransfusion, an autotransfusion program was designed for 10 patients undergoing hip-joint replacement surgery for arthrosis. 4 phlebotomies of 450 ml each were performed within 12 days. Blood samples were taken immediately before phlebotomy for blood hemoglobin (Hb), serum erythropoietin (Epo), reticulocyte count (ret) and erythrocyte 2,3-diphosphoglycerate (DPG). All 4 phlebotomies could be performed in 9/10 patients, and only 1 patient had significant symptoms (fatigue). The operation was performed 2 weeks after the last phlebotomy. None of the patients had recovered the initial Hb level at operation (24.8 +/- 9 per liter lower than initially), and they were all even more anemic after the operation (36.8 +/- 16.9 g/l lower than initially). Serum Epo increased from 13.6 +/- 7.2 IU to 30.6 +/- 12.2 (SD) IU per liter, and reticulocyte counts increased to a maximum of 3.68 +/- 1.69%. DPG increased in all patients except the one who had significant fatigue. It is concluded that the patients tolerated the phlebotomy program well but that a significant anemia developed. The compensatory increase in erythropoietin and reticulocyte count, adequate for this degree of anemia, was small compared to the increase seen at more severe anemia, indicating that there may be a role for pharmacological stimulation of erythropoiesis in blood predeposit programs.

Adult↗
PubMed1993

Evaluation of phlebotomy-induced erythropoietin production in the dog.

Erythropoietin (EPO) production in dogs was studied by reducing red blood cells with phlebotomy. In this study, the hemoglobin reduction rate (delta %Hb) was newly taken into account as the regulating factor for EPO production, and its usefulness to estimate the stimulating intensity to EPO production was examined. As the result, plasma EPO was highly correlated with delta %Hb showing the importance related to regulation of EPO production, in the increasing plasma EPO by different degrees of phlebotomy, in the change of plasma EPO through the anemia progress and recovery period after severe phlebotomy, and in the initial variation of plasma EPO induced by chronic mild phlebotomy. On the other hand, increasing EPO production appeared at least within 6 hr after acute severe phlebotomy, which revealed significantly higher plasma level compared with the mild chronic phlebotomy, suggesting the effect of time leading to red blood cell reduction on EPO production response. Simultaneously, considering an in vivo EPO half life of 8.4 hr calculated from plasma EPO disappearance after bilateral nephrectomy, endogenous plasma EPO accumulation should be taken into consideration in rapidly increasing of delta %Hb.

Anemia↗
PubMed1992

The effect of phlebotomy on serum erythropoietin levels in normal healthy subjects.

We evaluated endogenous serum erythropoietin (Epo) levels in 14 normal subjects (eight males and six females) after a single 400-ml phlebotomy. The subjects were followed up for 56 days. The hemoglobin (Hb) values of both males and females decreased to a nadir on days 3 to 7 post-phlebotomy. Hb values gradually increased, but did not completely recover to pre-phlebotomy levels by day 56. Serum Epo levels increased after 6 h post-phlebotomy, to 20.1 +/- 5.4 (mU/ml) in males and 20.7 +/- 7.0 in females, from the pre-phlebotomy levels of 14.6 +/- 4.0 in males and 13.4 +/- 4.1 in females, respectively. Epo levels continued to increase to peak levels of 25.5 +/- 6.3 in males and 28.7 +/- 11.5 in females on days 7 to 14 and thereafter decreased until day 56. Thus, the Epo response to a 400-ml phlebotomy was relatively small in magnitude and was not sufficient to initiate a significant increase in erythropoiesis. This finding suggests that the administration of recombinant human erythropoietin (rHu-Epo) may be effective for the prompt correction of anemia induced by autologous blood donation and for increasing the volume of predonated autologous blood.

Adult↗
PubMed2004

Erythropoietin production rate in phlebotomy-induced acute anemia.

OBJECTIVE: To estimate the rate of erythropoietin (EPO) production under physiological, conditions and to examine the regulatory mechanism of EPO production in response to acute phlebotomy-induced anemia. METHODS: Six sheep each underwent two phlebotomies in which the hemoglobin (Hb) was reduced to 3-4 g/dl over 4-5 h. The EPO plasma level, reticulocytes, Hb and EPO clearance were followed by frequent blood sampling. The EPO production rate was determined by a semi-parametric method based on a disposition decomposition analysis that accounts for the nonlinear disposition kinetics of EPO and corrects for time-dependent changes in the clearance. RESULTS: The controlled drop in hemoglobin resulted in an abrupt increase in the plasma EPO concentration (peak level 812+/-40 mU/ml, mean+/-CV%) that was followed by a rapid drop 2-4 days after the phlebotomy at a time when the sheep were still anemic (Hb=4.3+/-16 g/dl). The EPO production rate at baseline was 43+/-52 U/day/kg and the amounts of EPO produced over an 8 day period resulting from the first and second phlebotomy were 2927+/-40 U/kg and 3012+/-31 U/kg, respectively. CONCLUSIONS: The rapid reduction in the EPO plasma level observed 2-4 days following the phlebotomy cannot be explained solely by the increase in EPO clearance but also by a reduction in EPO production.

Acute Disease↗
PubMed2006

Effect of low central venous pressure and phlebotomy on blood product transfusion requirements during liver transplantations.

Correction of coagulation defects with plasma transfusion did not decrease the need for intraoperative red blood cells (RBC) transfusions during liver transplantations. On the contrary, it led to a hypervolemic state that resulted in an increase of shed blood. As well, plasma transfusion has been associated with a decreased one-year survival rate. The aim of the present prospective survey was to evaluate whether anesthesiologists could reduce intraoperative RBC transfusions during liver transplantations by changing their anesthesia practice, more specifically by maintaining a low central venous pressure (CVP), through restriction of volume replacement, elimination of all plasma transfusion and by using intraoperative phlebotomy during the transplantation. One hundred consecutive liver transplantations were prospectively studied during a two-year period and were compared to a retrospective series (1998-2002). A low CVP was maintained in all patients prior the anhepatic phase. Coagulation disorders were not corrected preoperatively, intraoperatively, or post-operatively unless uncontrollable bleeding. Phlebotomy and Cell Saver (CS) were used following pre-established criteria. Independent variables were analyzed in a univariate and multivariate fashion. The mean number of intraoperative RBC units transfused was 0.4 +/- 0.8. No plasma, platelets, albumin, or cryoprecipitate were transfused. Seventy-nine percent of the patients received no blood products during their liver transplantation. The average final hemoglobin value was 85.9 +/- 17.8 g/L. In 57 patients (58.2%), intraoperative phlebotomy and CS were used either together or separately. The one-year year survival rate was 89.1%. Logistic regression showed that avoidance of plasma transfusion, starting hemoglobin value and phlebotomy were significantly linked to liver transplantation without RBC transfusion. In conclusion, the avoidance of plasma transfusion and maintenance of a low CVP prior to the anhepatic phase were associated with a decrease in RBC transfusions during liver transplantations. Previous reports indicating that it is neither useful nor necessary to correct coagulation defects with plasma transfusion prior to liver transplantation are further corroborated by this prospective survey. We believe that this work also supports the practice of lowering CVP with phlebotomy in order to reduce blood loss, during liver dissection, without any deleterious effect.

Adult↗