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PubMed1996

Nursing strategies to minimize blood loss associated with phlebotomy.

Blood loss associated with phlebotomy is significant in critically ill adults. Iatrogenic anemia may result and impose unnecessary stress on the cardiovascular and respiratory systems and may require allogeneic blood transfusions. Many strategies exist under nursing's direct control to decrease blood loss associated with phlebotomy. In the past, nursing effectively implemented many of these strategies in patients at high risk of anemia, such as pediatric, neonatal, transplant, or chronic renal failure patients, as well as patients who are Jehovah's Witnesses. Implementation of these strategies are needed for all critically ill patients because allogeneic blood transfusions carry infectious risk and because complications and chronic critical illness cannot be predicted reliably. Incorporation of these strategies into daily practice as well as the development of blood conservation programs represent imminent challenges for nursing.

Adult↗
PubMed2006

Effects of phlebotomy therapy on cytochrome P450 2e1 activity and oxidative stress markers in dysmetabolic iron overload syndrome: a randomized trial.

AIM: To assess the effects of iron removal on cytochrome P450 2E1 activity and oxidative stress in dysmetabolic iron overload syndrome. METHODS: Forty-eight patients were randomized to phlebotomy therapy consisting of removal of 300-500 mL of blood every 14 days until serum ferritin levels dropped under 100 microg/L or to follow-up without phlebotomy therapy. Cytochrome P450 2E1 activity was measured at baseline and at the end of treatment by using the 6-hydroxychlorzoxazone/chlorzoxazone blood metabolic ratio, 2 h after the intake of 500 mg of chlorzoxazone. RESULTS: In the treatment group, a mean of 3.9 +/- 1.3 L of blood was removed and serum ferritin levels dropped from 715 +/- 397 to 74 +/- 34 microg/L. Variation of cytochrome P450 2E1 activity was not significantly different between the 2 groups (0.07 +/- 0.26 vs. 0.03 +/- 0.19, P = 0.36). In the treatment group, low-density lipoprotein cholesterol and vitamin E were lowered after treatment compared with control group (-0.15 +/- 0.51 vs. 0.24 +/- 0.58, P = 0.002 and -1.3 +/- 4.4 vs. 2.3 +/- 5.2, P = 0.03, respectively). Inversely, vitamin C was increased (0.5 +/- 3.5 vs. -1.8 +/- 3.9, P = 0.03). CONCLUSIONS: In dysmetabolic iron overload syndrome, reduction of iron stores does not significantly influence cytochrome P450 2E1 activity but is associated with a significant decrease of low-density lipoprotein cholesterol, suggesting that venesection therapy may be a suitable option in these patients.

Ascorbic Acid↗
PubMed2000

Phlebotomy increases cadmium uptake in hemochromatosis.

The intestinal absorption of the nephrotoxic environmental pollutant cadmium increases markedly when iron stores are depleted. This may be mediated by an up regulation of the recently identified mucosal transporter DMT1 (Nramp2 or DCT1) for divalent cations. We tested whether the highly increased iron absorption in hereditary hemochromatosis (HH) was accompanied by an enhanced absorption of cadmium and lead. Cadmium and lead in blood and iron status markers were determined in 21 nonsmoking subjects with HH genetically tested for the HFE mutations and in 21 nonsmoking controls matched for age and sex. In subjects with HH on maintenance phlebotomy treatment, blood concentrations of cadmium, but not lead, were significantly higher than in paired controls. There was a strong age-independent positive association between blood cadmium and the number of years of phlebotomy treatment. Blood lead showed a similar but less pronounced consequence of treatment. All HH subjects with lower blood cadmium than the corresponding controls had either no mutation in the HFE gene, were not phlebotomized, or were phlebotomized for only a limited time. Our findings indicate that the treatment rather than the disease increased the cadmium uptake in homozygous HH. Further studies are needed to confirm whether the disease decreased cadmium absorption and whether the absorption was dependent on the genotype.

Absorption↗
PubMed2006

The efficacy of a medical virtual reality simulator for training phlebotomy.

OBJECTIVE: The present study compared the effectiveness of a virtual reality (VR) simulator for training phlebotomy with that of a more traditional approach using simulated limbs. BACKGROUND: Phlebotomy, or drawing blood, is one of the most common medical procedures; yet, there are no universal standards for training and assessing performance. The absence of any standards can lead to injuries and inaccurate test results if the procedure is improperly performed. METHOD: Twenty 3rd-year medical students were trained under one of the two methods and had their performance assessed with a 28-item checklist. RESULTS: The results showed that performance improvements were limited to those who trained with the simulated limbs, and a detailed comparison of the two systems revealed several functional and physical differences that may explain these findings. CONCLUSION: Participants trained with simulated limbs performed better than those trained with a VR simulator; however, the metrics recorded by the VR system may address some aspects of performance that could eventually prove beneficial. APPLICATION: The present study highlights the potential for medical simulators to improve patient safety by enabling trainees to practice procedures on devices instead of patients. Applications of this research include training, performance assessment, and design of simulator systems.

Adult↗
PubMed2000

Juvenile hemochromatosis associated with B-thalassemia treated by phlebotomy and recombinant human erythropoietin.

Juvenile hemochromatosis is a rare genetic disorder that causes iron overload. Clinical complications, which include liver cirrhosis, heart failure, hypogonadotropic hypogonadism and diabetes, appear earlier and are more severe than in HFE-related hemochromatosis. This disorder, therefore, requires an aggressive therapeutic approach to achieve iron depletion. We report here the case of a young Italian female with juvenile hemochromatosis who was unable to tolerate frequent phlebotomy because of coexistent ss-thalassemia trait. The patient was successfully iron-depleted by combining phlebotomy with recombinant human erythropoietin.

Adrenal Cortex Hormones↗
PubMed2006

Causes of anaemia in very low birth weight infants. Phlebotomy losses are not the first accused.

AIM: The specific aim of the study was to determine the correlation between the severity of pathology, the amount of blood removed for diagnostic purposes in the 1st week of life and the incidence of early anaemia in very low birth weight (VLBW) infants. METHODS: We recorded the level of haemoglobin (Hb) and haematocrit (Ht) in each of the 50 infants entered in the study at their admission in our neonatal intensive care unit (NICU) and at the age of 8 days. We quantified for each infant the blood drawn for clinical purpose during the 1(st)week of life, using microanalytic techniques for all types of analysis performed. Using the neonatal therapeutic intensive score system (NTISS) we divided all patients into 2 groups: group A= mild light pathology; group B= severe pathology. RESULTS: There was statistically significant difference between the percent decrease of Hb and Ht with reference to the birth weight in the 2 groups. Logistic regression analysis indicated a strong correlation (P = 0.009) between higher degree of illness severity and higher percent decrease of Hb and Ht. The difference due to the amount of phlebotomy losses was not significant. CONCLUSIONS: To our knowledge, this study is the first that strongly suggest that phlebotomy losses is not the main cause of anaemia in VLBW preterm infants in the 1st week of life, when a policy of strictly attention to the amount of blood removed is performed.

Age Factors↗
PubMed1982

Hemoglobin Osler: report of a new family with exercise studies before and after phlebotomy.

Five members of a new family with hemoglobin Osler are described. Exercise studies were performed before and after phlebotomy in one patient. These studies demonstrated that anaerobic threshold was directly related to hematocrit. Our data suggest that the elevation of red cell mass seen with this high oxygen affinity hemoglobin is an appropriate physiologic response which improves tissue oxygen delivery. Despite the increase in whole blood viscosity associated with erythrocytosis, our data do not support the use of therapeutic phlebotomy to improve exercise performance in patients with hemoglobin Osler.

Adult↗
PubMed1985

Monitoring of intensive phlebotomy therapy in iron overload by serum ferritin assay.

Four patients with idiopathic hemochromatosis were treated with intensive phlebotomy therapy. In 1 to 2 years, 8.8-16.7 g iron was removed. In three out of four patients hemoglobin levels fell at the end of therapy. Serum ferritin was continuously measured during therapy. The greatly elevated serum ferritin levels normalized or decreased to subnormal levels in all patients after therapy. Despite some fluctuations in the first phase of therapy, the fall in serum ferritin was regular with halving of the ferritin levels after about 50% of the excess iron was removed. The normalization of serum ferritin occurred in advance of the hemoglobin decrease at the end of therapy, indicating that in the later stages of therapy the normal iron stores are also depleted. It is emphasized that serum ferritin measurements are useful for monitoring of intensive phlebotomy therapy, and in particular to indicate the end of therapy before anemia develops.

Adult↗
PubMed1989

Effect of phlebotomy on the ferritin iron content in the rat liver as determined morphometrically with the use of electron energy loss spectroscopy.

Phlebotomy of untreated and iron-loaded rats results in a significant decrease in total liver iron. In iron-loaded rats a marked decrease in iron-containing particles is observed ultrastructurally in lysosomes and cytoplasm of hepatic sinusoidal cells but not in parenchymal cells. This remarkable phenomenon was further investigated in a morphometric study, based on element-specific (iron) distribution images made in situ in the parenchymal cell by means of electron energy loss spectroscopy. With the use of this technique it could be shown that in spite of phlebotomy the ferritin iron content of the iron-loaded liver parenchymal cell is not decreased.

Animals↗
PubMed1983

Acute effects of phlebotomy on right ventricular size and performance in polycythemic patients with chronic obstructive pulmonary disease.

To assess the acute effects of phlebotomy on right ventricular size and performance, gated equilibrium radionuclide angiography was used to evaluate 10 patients with severe chronic obstructive pulmonary disease and erythrocytosis (hematocrit greater than 55%). The mean right ventricular ejection fraction was abnormal before (0.38) but not after (0.43) phlebotomy, and the increase was highly significant (p less than 0.001). Similarly, the right ventricular end-diastolic area decreased significantly from 588 to 505 pixels (p less than 0.02). No significant changes occurred on the left side. Cardiac output was unchanged or slightly increased. Thus, assuming that afterload was unchanged, as reported by other investigators, the data herein are consistent with the hypothesis that a normalization in preload shifts the Starling curve, resulting in improved right ventricular performance with preservation of the cardiac output.

Adult↗
PubMed1994

Response to repeated phlebotomies in patients with non-insulin-dependent diabetes mellitus.

Regardless of type, uncontrolled diabetes represents a serious disruption of fuel homeostasis with consequences throughout the body. This may hamper the applicability of predeposited autologous blood transfusion in diabetic patients because metabolic changes are expected as a consequence of repeated bleeding. We undertook this study to determine whether the presence of non-insulin-dependent diabetes mellitus (NIDDM) influences the erythropoietin (EPO) response to repeated phlebotomies with respect to normal subjects. We included 22 consecutive patients scheduled for major surgery during a 2-year period in which clinical and metabolic complications were excluded and renal and liver function was considered unaffected. Selected biochemical and hematologic variables were serially measured during donation of several units of blood in a 12- to 29-day period. Bleeding produced a significant decrease in serum glucose, cholesterol, triglyceride, and apoprotein B concentration in diabetic patients. Except for glucose, this effect was not observed in controls. Both groups were comparable with respect to initial hemoglobin concentrations and all hematologic variables measured. The decrease in hemoglobin concentration did not produce clinical symptoms in these patients, and recovery was regarded as normal in both groups. Serum EPO levels in diabetic patients were negatively influenced by the initial hemoglobin A1c (HbA1c) proportion. Moreover, three nonrespondent diabetic patients with poor glycemic control responded normally 6 to 13 months later, in a second operation, when glycemic control had improved significantly. In conclusion, NIDDM may limit the donation of requested units for major surgery only if poor glycemic control is present. When possible, phlebotomies should be delayed and metabolic control reinforced.

Adult↗
PubMed1994

Effects of phlebotomy on a patient with secondary polycythemia and angina pectoris.

A 67-year-old man with polycythemia, secondary to chronic obstructive pulmonary disease, had angina attacks at rest treated successfully by supplementing conventional therapy with frequent phlebotomies. Although phlebotomy reduces arterial oxygen content, it also decreases blood viscosity, improves peripheral oxygen consumption and thus yields the clinical benefit.

Aged↗
PubMed1988

Conjunctival oxygen tension monitoring during a controlled phlebotomy.

A decrease in the conjunctival oxygen tension (Pcjo2) and conjunctival index (Pcjo2/Pao2) has been shown to be an early marker of acute blood loss. We sequentially measured Pcjo2, Pcjo2/Pao2, blood pressure, and pulse rate in five healthy adults after controlled phlebotomy of 450 mL and after intravenous fluid repletion. No significant changes occurred in either the Pcjo2 or Pcjo2/Pao2 after phlebotomy or after fluid replacement. We conclude that a blood loss of 450 mL in healthy, euvolemic adults is insufficient to perturb the conjunctival index. The lower limits of sensitivity of changes in Pcjo2 and Pcjo/Pao2 in response to acute blood loss remain to be established.

Adult↗
PubMed1975

Physiologic effects of hyperventilation and phlebotomy in baboons: systemic and cerebral oxygen extraction.

Eighteen anesthetized baboons were studied to determine the effects of passive hyperventilation and phlebotomy on oxygen transport. After 1 hour of hyperventilation a significant increase in the red cell affinity for oxygen occurred in vivo. This was not associated with any significant changes in cardiac output, oxygen consumption, or in lactic acid production. There was a 40% decrease in cerebral blood flow, a 10 mm Hg decrease in the pulmonary artery Po2 level, and a 17 mm Hg decrease in the jugular venous Po2 level. After 1 hour of hyperventilation, the plasma inorganic phosphorus level decreased significantly, the red cell ATP level decreased slightly, and the red cell 2. 3 DPG level increased significantly, indicating that inorganic phosphorus had been removed from the blood during hyperventilation. Passive hyperventilation was maintained, and the baboons were bled 32% of their red cell volume. The blood volume was partially restored with nonbuffered isotonic saline. One hour after the phlebotomy and volume restoration (2 hours of hyperventilation) there were no changes in oxygen consumption, cardiac output, cerebral blood flow, or blood lactate levels, but the pulmonary artery Po2 level was decreased by 15 mm Hg, and the jugular venous Po2 level was decreased by 20 mm Hg. Systemic oxygen consumption was not affected by the significant decrease in pulmonary artery Po2.

Animals↗
PubMed1990

Exercise-induced changes in left ventricular function after phlebotomy in patients with polycythemic COPD.

The exercise capacity of polycythemic COPD patients has been shown to improve after phlebotomy, possibly because of reduction of ventricular afterload by decreased blood viscosity, resulting in increased cardiac output. Ten patients with polycythemic COPD and mean hematocrit 62% were studied at rest and during exercise before and after reduction of mean hematocrit to 50% by repeated phlebotomy. Pulmonary function was evaluated by physiologic exercise testing on a bicycle ergometer. Cardiac function was evaluated by rest and exercise RNVG. Significant increase in exercise tolerance and maximal oxygen uptake at peak exercise, with significant reduction in mean systemic BP, were demonstrated. Ejection fractions did not change, but dV/dt for ejection from the left ventricle at peak exercise improved significantly. Mean SV counts, ESV counts, and EDV counts were measured and the fractional increase with exercise compared for prephlebotomy and postphlebotomy, assuming that resting volumes would not change. ESV counts and EDV counts were both proportionately, though not significantly, reduced postphlebotomy. The data tend to support the hypothesis that the afterload on the left ventricle is reduced, with resulting improved myocardial contractility and left ventricular function. Improved peripheral oxygen uptake may also be a factor.

Cardiac Output↗
PubMed1977

Treatment of porphyria cutanea tarda with chloroquine and phlebotomy.

Treatment of porphyria cutanea tarda (PCT) with chloroquine risks serious side-effects so we have combined it with phlebotomy. One to four venesections were performed before the administration of chloroquine in 10 PCT patients. Equally high excretion of urinary porphyrins was achieved but the side-effects were reduced. Chloroquine may be used as a provocative diagnostic test for patients with a questionably latent PCT but this is safe if phlebotomy is performed beforehand.

Adult↗
PubMed1983

Zinc, copper, magnesium, and calcium in blood and plasma after phlebotomy.

Zinc levels in plasma and whole blood were investigated in 2 groups of blood donors. The first group consisted of 19 men and 11 women who donated blood for the first time and were followed during 3 phlebotomies. The second group comprised 44 men with 9 or more previous blood donations, their blood being analysed on a single occasion. Plasma concentrations of copper, magnesium, calcium and ferritin were also analysed. The zinc levels in whole blood and plasma in the second group were significantly lower as compared to the first group (P less than 0.001). Furthermore, the second group had significantly higher levels of copper and copper:zinc quotient in plasma as compared to those of the new blood donors (P less than 0.001). Our results indicate that besides the earlier known effect of blood donation on iron stores, there are also signs of zinc depletion when judged from the zinc levels in plasma and in erythrocytes. No significant changes in calcium and magnesium concentrations were seen during phlebotomy.

Adolescent↗
PubMed1991

Variations in serum erythropoietin and transferrin receptor during phlebotomy therapy of hereditary hemochromatosis: a case report.

Serum levels of transferrin receptor and erythropoietin were determined in 2 patients with hereditary hemochromatosis undergoing phlebotomy therapy. The objective of the study was to determine changes in serum transferrin receptor and serum erythropoietin occurring during therapy, and to investigate if such changes could be useful to monitor the therapy. The study showed that serum transferrin receptor, and to a lesser extent serum erythropoietin, may be better parameters than serum ferritin as indicators of when phlebotomy should be discontinued. The most sensitive parameter, however, appeared to be the serum transferrin receptor/ferritin ratio.

Adult↗