Infusion Of Red Cells Research Articles

Tachycardia and fever after packed red cell (PRC) infusion: A case report

ABSTRACT A 56-year-old female patient with a body weight of 60 kg was brought to the hospital with hematemesis and received one unit of packed red cells (PRCs) for this condition. After 30 min, the patient experienced tachycardia of 120 beats/min and an increased body temperature of 102°F. The patient had no relevant medical history of allergy or similar episodes in the past. The patient was not suffering from any coagulopathies or sickle cell anaemia, which is a prevalent condition in the region. The patient was receiving the PRC for the first time. After this event, the infusion was stopped and immediately injection meropenem, pantoprazole and ondansetron IV were administered. The patient’s condition normalised after 6 h. No re-challenge was given after the recovery of the patient. Suspected ADR was analysed according to the World Health organization (WHO) causality assessment scale and the causality was “Possible”. Meticulous monitoring and prompt therapy were provided. The patient was discharged after observing for 24 h. The adverse drug reaction was possibly caused due to the PRCs.

Red cell infusion but not saline is effective for volume expansion in preterm piglets.

A common first-line treatment for supporting cardiovascular function in preterm infants is volume expansion using saline, but this does not improve outcomes. This study aimed to determine if volume expansion with saline increases blood volume, blood pressure and cerebral oxygenation; and if volume expansion with packed red blood cells (RBC) is more effective. We hypothesized that RBC infusion is more effective than saline for increasing blood volume and maintaining cardiovascular function and cerebral oxygenation. Five groups of preterm piglets (98/115d gestation) were infused with saline (10 or 20 mL/kg) or RBC (10 or 20 mL/kg) or no treatment. Blood volume, blood pressure, central venous pressure, heart rate, carotid flow, cerebral oxygenation, arterial pH, base excess, and lactate levels were assessed for 6 h after treatment started. Both RBC groups had significant increases in blood volume, and improved measures of cardiovascular function, cerebral oxygenation and metabolic acidosis. Saline infusion did not increase blood volume or measures of cardiovascular function, cerebral oxygenation or metabolic acidosis. The results suggest that the deteriorating cardiovascular function in the hours after birth in preterm piglets, and possibly in premature babies, may be reversed or halted by more effective support of blood volume. Blood volume decreases after birth in preterm piglets and this decrease is associated with deteriorating cardiovascular function and cerebral oxygenation. Infusion of saline does not increase blood volume nor prevent deterioration in cardiovascular function. Infusion of packed red blood cells results in an increase in blood volume and improvements in cardiovascular function and cerebral oxygenation. Deteriorating cardiovascular function in the hours after birth in preterm piglets, and possibly in human preterm neonates, may be reversed or halted by more effective support of blood volume.

Massive transfusion protocol: Need of the hour - A tertiary care centre experience.

Massive transfusion (MT) in critically ill patients during major volume losses can lead to serious adverse outcomes. Studies have reported that rampant red cell infusion for maintaining perfusion support has had detrimental effects on patients' short- and long-term survival rates. Evidence-based studies quote the importance of maintaining blood product ratio during massive hemorrhage and ensuring good outcomes with the least morbidity and mortality. It is an observational study to compare the ratio of usage of blood products and their role in the outcome of MT cases. A total of 70 patients (29 females and 41 males) who received MT were included in the study. There was no fixed ratio of packed red blood cells (PRBC) to blood components for patients with massive hemorrhage. The average ratio of PRBC: fresh frozen plasma (FFP):platelet concentrate (PC) was 1:0.9:0.6. However, blood component therapy with PRBC: FFP ratio between 1 and 2 was associated with a significant rise in post-acute phase hemoglobin value (P value = 0.018). Appropriate blood component therapy during the acute bleeding phase in massively transfused patients can further decrease the transfusion demand and transfusion-related complications. There is a need to adhere to the MT protocol for the clinical areas requiring MT in the developing world too.

Analysis of Factors Influencing the Effect of Red Blood Cell Suspension Infusion in Children

Objective: The related factors of no improvement of hypoxia and ineffective infusion were analyzed to provide new ideas, clinical observation and evaluation pathway for RBC transfusion in clinical children. Methods: Retrospective analysis from January 2020 to December 2020, Guangzhou women and children’s medical center hospital in the emergency observation room of 249 children under 1 month to 18 years of blood cell suspension infusion, analyze the clinical effect of red blood cell infusion and children gender, age, fever after transfusion, disease type, delay transfusion. The possible influencing factors were analyzed by logistic regression. Results: Invalid transfusion was associated with the type of transfusion product (P = 0.032), logistic regression analysis showed that patients infused with washed RBC suspension were 3.231 times more likely to not achieve the expected effect than those infused with RBC suspension (P = 0.025). Failure transfusion was associated with the type of transfusion products. In ineffective transfusion was closely related to post-transfusion fever (P P P = 0.031). Logistic regression analysis showed that fever after transfusion was a risk factor for no improvement of hypoxia (OR = 5.809, P = 0.001), and the improvement of hypoxia in adolescent children was 10.744 times higher than that of infants (0 - 3 years old). Late transfusion hypoxia improvement was 4.212 times more likely to achieve no effect than timely transfusion. If ineffective infusion of red blood cells is considered and hypoxia after transfusion is not improved, univariate suggests a close correlation with fever after transfusion (P = 0.002), logistic regression analysis showed that fever after transfusion was an independent risk factor (OR = 7.258, P = 0.002). Conclusion: There was no correlation between the ineffective transfusion of red blood cells and the type of disease affected in the child. Infusion of red cell suspension has an advantage over the wash red cell infusion. Ineffective RBC transfusion and no improvement in hypoxia after transfusion were closely related to post-transfusion fever, with no difference between children in all age groups. Red blood cell infusion in pediatric clinical treatment activities should pay attention to adolescent children, especially female children to give more attention, and give timely red blood cell infusion as much as possible.

Pre-transplant donor-type red cell transfusion is a safe and effective strategy to reduce isohemagglutinin titers and prevent donor marrow infusion reactions in major ABO-mismatched transplants.

ABO incompatibility is not a barrier to allogeneic stem cell transplant but may result in acute hemolytic reactions. As stem cell product manipulation is cumbersome, we are reporting the effectiveness and safety of donor-type red cell infusion as a method of reducing acute hemolytic reaction while using marrow as stem cell source. In major ABO-mismatched bone marrow transplants, manipulation of marrow product requires expertise and expensive equipment, which may not be readily available to transplant centers in low- and middle-income regions. The aim behind our study is to report a safe and effective strategy to reduce isohemagglutinin titers and prevent donor marrow infusion reactions in major ABO-mismatched transplants. We retrospectively analyzed 303 consecutive allogeneic bone marrow transplants (BMTs) for beta thalassemia major, between August 2015 and March 2020, with either major (n = 41) or bidirectional (n = 14) mismatches. When isohemagglutinin titers were 1:32 or higher, donor-type packed red blood cell was divided into 4 aliquots, irradiated and administered over 4 days at incremental volumes. Patients were observed for hemolytic reaction, and if no reaction, bone marrow was infused without manipulation. Out of 55 patients, 20 received donor-type blood infusion. Twelve patients showed evidence of mild hemolysis. None developed severe hemolytic or anaphylactic reaction. Titers were rechecked in 14 patients and all had reduction in titers, except for one. Our experience demonstrated that donor-type PRBC infusion is safe and effective in preventing acute hemolysis in major ABO-mismatched stem cell transplants even with bone marrow as graft source.

Moxibustion with deferasirox results in safe, accelerated, and sustained cardiac iron chelation for a young Diamond Blackfan Anemia patient: An integrative case report

Diamond Blackfan Anemia (DBA) is a rare blood disorder of bone marrow failure typically identified in the first year of life. Due to treatment limitations, nearly all DBA patients are reliant upon chronic red cell infusion for some period of their lives. Repeat blood transfusion invariably leads to iron overload, which creates significant and life-threatening side effects. In this case report, a female child of 2 years and 8 months with DBA was diagnosed via T2* MRI imaging with potentially emergent levels of cardiac iron overload as a result of chronic red cell infusion. According to Chinese, Japanese, and integrative medicine principles, moxibustion was applied externally in conjunction with the prescribed oral chelation agent, deferasirox (DFX), over a period of six months. Analysis of repeat imaging at six months showed complete removal of cardiac iron and a one-third decrease in hepatic iron. In addition, there was no evidence of known risks to high-dose chelation, including renal, aural, or ocular damage. Follow-up examination two years after initial imaging showed no evidence of cardiac iron deposition with hepatic iron levels below minimum levels recommended for chelation despite the medical necessity of continued red cell infusion. This case study suggests that an integrative medical approach combining DFX with moxibustion may safely accelerate and sustain iron chelation for transfusion-dependent DBA patients. Recommendations for a successful approach to integrative iron chelation are provided in the case discussion.

In-Vivo Adsorption of Iso-Haemagglutinin (IHA) Antibodies By Donor Type Red Cell Transfusion during Conditioning Is a Safe and Effective Method to Overcome Major ABO Incompatibility-Related Acute Hemolytic Reactions in Stem Cell Transplant Using Bone Marrow As Stem Cell Graft Source

Introduction: ABO blood group incompatibility is not a barrier to performing allogeneic stem cell transplant, but may result in life-threatening acute hemolytic reactions as well as pure red cell aplasia. As stem cell product manipulation is cumbersome and may entail cell loss, attempts have been made in the past to reduce IHA titers in-vivo either by donor type red cell transfusion or using frozen plasma in peripheral blood stem cell (PBSC) transplants (Scholl et al. Transfusion 2005; Damodar et al. BMT 2005). The efficacy of such strategies have not been described in Bone marrow transplant (BMT) setting. We are reporting the effectiveness and safety of donor type red cell infusion during conditioning as a method of reducing acute hemolytic reaction during transplant while using unmanipulated marrow as stem cell source (BMT). Materials and Methods: We retrospectively analyzed 241 consecutive allogeneic BMTs for beta thalassemia major, between August 2015 and July 2019 out of which 82 were ABO mismatched transplants, either major (n=30) or minor (n=40), or bidirectional (n =12) mismatched. Infusion of donor type red blood cell during conditioning after the infusion of Anti-thymocyte globulin (ATG) and post-transplant complication of acute hemolysis were determined by retrospective review of individual medical records. When there is a major ABO incompatibility and IHA titers against the donor were > 1:64, a single unit of donor type Packed Red Blood cell (PRBC) was divided into 4 aliquots, irradiated and administered over 4 days at increasing incremental volumes once daily over 4 days if tolerated (Day 1 - 5 ml, Day 2 - 10ml, Day 3- 20-30 ml, Day 4 - 40-60 ml) (Fig.1). Patients were watched carefully for febrile reactions and hemoglobinuria and mild reactions were tolerated. If no clinical evidence of severe hemolytic reaction, bone marrow was infused without manipulation on the day of transplant. Results: Out of 30 patients with major ABO incompatibility, 13 patients had titers more than 1:64 (highest was 1:2048) and hence received donor type PRBC infusion in small incremental doses. Eight patients showed evidence of some hemolysis (4 during infusion of donor type PRBC aliquot and 4 showed increase in indirect bilirubin with marrow infusion) which was managed conservatively with hydration. None of the patients developed severe hemolytic or anaphylactic reaction at the time of marrow infusion. Post infusion of donor type blood, titers were checked in 7 patients. 6 patients had significant reduction in titers (all were less than 1:32) except for 1(titers increased to 1:4096), which was not considered clinically relevant as he tolerated 100mls of donor type PRBC. He also tolerated marrow infusion without any evidence of severe hemolytic reaction. Four more patients with bidirectional mismatch had IHA titers against the donor more than 1:64, hence the same procedure was followed. One of them had mild hemoglobinuria during donor type PRBC infusion and 3 patients had mild hemoglobinuria with rise in indirect bilirubin at the time of marrow infusion. All patients were managed conservatively with hydration. Conclusion: Our experience demonstrated that donor-type PRBC infusion as a method of in-vivo adsorption of IHA antibodies against donor is safe and effective in preventing acute hemolysis in major ABO-mismatched stem cell transplants even in the context where bone marrow is used as graft source. This simple method in addition to avoiding the problems related to product manipulation can also be safely and easily performed in resource limited settings. Disclosures No relevant conflicts of interest to declare.

Average Monthly Cost of Iron Chelator Treatment in Adult Patients with Sickle Cell Disease

Introduction: Iron overload in adult patients with sickle cell disease (SCD) can lead to variety of complications like liver dysfunction/cirrhosis, cardiac enlargement, diabetes mellitus, hypogonadism and arthropathy. These complication can be prevented by iron chelation therapy .We did retrospective analysis to find incidence of iron over load in this population and also did a survey to find the insurance status in this population. Methods: We take care of approximately 300 adult patients with SCD at out hematology clinic. We did retrospective analysis to investigate the prevalence of iron overload in this population. We also did survey on 100 adult patients with SCD to find out about the insurance converge for them. Web search was done to find out the average monthly cost of iron chelators. Results: On retrospective analysis of 458 adult patients with SCD, we found that 117/458(25.58%) had iron over load. Majority of them, 93/117 were SS type of SCD. Results of survey done on 100 adult patients with SCD showed that 61 had Medicaid, 2 were free care, 25 had Medicare and 12 had private insurance. The average monthly cost of Deferiprone is $ 18762, while that of Deferasirox is $ 13,082. Conclusions: Iron over load is a common complication affecting a quarter of the adult patients with SCD. The treatment of iron overload is expensive, as just the iron-chelator therapy costs approximately 160 to 220 K per year. In an attempt to minimize additional iron accumulation in our chronically transfused patient population we encourage the schedule of exchange of 1 unit phlebotomy and 1 unit of red cell infusion every two weeks. Disclosures No relevant conflicts of interest to declare.

Clinical outcomes of synchronous revascularization on patients concomitant carotid and coronary artery severe stenosis

To analyze the outcomes of synchronous revascularization for patients concomitant carotid and coronary artery severe stenosis. From May 2012 to April 2014, 12 cases who received one-stage operation was retrospective analyzed, including the characteristics, methods of treatment, perioperative complications and health survey 30 days post procedure. Two subgroups were divided according to the different treatment methods on carotid artery, WIC and SF-36 scale were applied to compare the basic condition and recovery situation between 2 groups, the hospital stay time, costs, ventilation time, drainage and blood transfusion volume were also be compared. Totally 30 coronary vessels 8 carotid endarterectomy (CEA) and 5 carotid artery stenting (CAS) were performed on 12 patients. One patient also received coronary artery bypass grafting and bilateral carotid artery revascularization (CEA on right and CAS on left). Two (16.67%) minor stroke, 1 (8.33%) TIA, 1 wound infection occurred within 30 days post procedure, and 11 (91.67%) received blood component transfusion. No myocardial infarction and death occured. The average hospital stay time were (36.5 ± 25.3) days, ventilator application (37.5 ± 31.2) hours, postoperative drainage volume from pericardial and mediastinal was (347.92 ± 105.69) ml, infusion of concentrated red cell was 4.3 U. WIC was (5.57 ± 1.51) in CEA and (4.25 ± 1.50) in CAS subgroup, there was no significantly statistical difference (t = 1.40, P > 0.05). the results of SF-36 was (3.63 ± 1.76) and (5.44 ± 1.05) in CEA and CAS subgroup, there was no significantly statistical difference (t = -1.85, P > 0.05). In hospital stay time, ventilator application time, transfusion and drainage volume, hospitalization costs were also no significant statistical difference between two groups. The early outcome of synchronous revascularization on concomitant carotid and coronary severe stenosis disease is satisfactory. The clinical results are similar in the CEA and CAS subgroup.

Balanced versus unbalanced salt solutions: what difference does it make?

The infusion of crystalloid solutions is a fundamental part of the management of critically ill patients. These solutions are used to maintain the balance of water and essential electrolytes and replace losses when patients have limited gastrointestinal intake. They also act as carriers for intravenous infusion of medication and red cells. The most commonly used solution, 0.9% saline, has equal concentrations of Na(+) and Cl(-) even though the plasma concentration of Na(+) normally is 40meq/L higher than that of Cl(-). The use of this fluid thus can produce a hyperchloremic acidosis in a dose-dependent manner, but it is not known whether this has clinical significance. The first part of this article deals with the significance of Na(+) and Cl(-) in normal physiology. This begins with examination of their roles in the regulation of osmolality, acid-base balance, and generation of electrochemical gradients and why the concentration of Cl(-) normally is considerably lower than that of Na(+). The next part deals with how their concentrations are regulated by the gastrointestinal tract and kidney. Based on the physiology, it would seem that solutions in which the concentration of Na(+) is "balanced" by a substance other than Cl(-) would be advantageous. The final part examines the evidence to support that point. There are strong observational data that support the notion that avoiding an elevated Cl(-) concentration or using fluids that reduce the rise in Cl(-) reduces renal dysfunction, infections, and possibly even mortality. However, observational studies only can indicate an association and cannot indicate causality. Unfortunately, randomized trials to date are far too limited to address this crucial issue. What is clear is that appropriate randomized trials will require very large populations. It also is not known whether the important variable is the concentration of Cl(-), the difference in concentrations of Na(+) and Cl(-), or the total body mass of Cl(-).

Résultats des échanges transfusionnels partiels chez 42 patients drépanocytaires homozygotes au CHU de Brazzaville

The standard of care for major sickle cell diseases in crisis is based on blood transfusion, but this remains a risky therapy in sub-Saharan Africa. The objective of this retrospective and prospective study was to assess exchange transfusion (ET) in homozygous sickle cell disease between 1st July 2005 and 30th June 2008 at the transfusion centre of university hospital of Brazzaville. The ET technique used was manual and made of three stages: bleeding, infusion of solution, and infusion of red cell concentrate. Clinical and biological assessments were done before and after exchanges. The indication for ET were: pregnancy (19 cases); strokes (seven cases); vaso-occlusive crisis (five cases), priapism (four cases), cardiac failure (three cases) and miscellaneous (four cases), the values of hematocut in red cell blood bag between 0.55 and 0.70 (median 0.65). The median haemoglobin level before exchange was about 5.8 g/dl (4.1–7.4 g/dl), that of HbS from haemoglobin electrophoresis about 98.4 % (94.6–100 %). Before the exchanges, viral serological tests were done with the following results: two patients with HBV antigen positive and one patient antibodies to HCV. In acute situation interval between exchanges is 3 to 10 days, whereas during chronic situation is between 14 to 28 days. No major immediate complications have been observed. Clinical situation after exchange characterized by stabilization of cerebral vascular stroke and over and control of one case of priapism complications. Assessment after exchange showed the following results: medium rate of Hb level: 9.5 g/dl (an increase of 3.7 g/dl); medium percentage of HbS reduced to 46.8 % (approximately a decrease of 51.6 %). Patient's serological status to HCV changed for one patient. This study illustrates the benefit and the limitations of the transfusion exchange during sickle cell disease in sub-Saharan Africa.

Can latent heat safely warm blood? – in vitro testing of a portable prototype blood warmer

BackgroundTrauma/retrieval patients are often in shock and hypothermic. Treatment of such patients usually involves restoring their blood volume with transfusion of blood (stored at 2°C – 6°C) and/or crystalloids or colloids (stored at ambient temperature). Rapid infusion of these cold fluids can worsen or even induce hypothermia in these patients. Warming of intravenous fluids at accident sites has traditionally been difficult due to a lack of suitable portable fluid warmers that are not dependent on mains electrical or battery power. If latent heat, the heat released when a liquid solidifies (an inherently temperature limiting process) can warm intravenous fluids, portable devices without a reliance on electrical energy could be used to reduce the incidence of hypothermia in trauma patients.MethodsRapid infusion of red cells into patients was timed to sample typical clinical flow rates.An approved dry heat blood warmer was compared with a prototype blood warmer using a supercooled liquid latent heat storage material, to warm red cells whilst monitoring inlet and outlet temperatures. To determine the effect of warming on red cell integrity compared to the normal storage lesion of blood, extracellular concentrations of potassium, lactate dehydrogenase and haemoglobin were measured in blood which had been warmed after storage at 2°C – 6°C for 1 to 42 days.ResultsA prototype latent heat fluid warmer consistently warmed red cells from approximately 4°C to approximately 35°C at typical clinical flow rates. Warming of stored blood with latent heat did not affect red cell integrity more than the approved dry heat blood warmer.ConclusionUsing latent heat as an energy source can satisfactorily warm cold blood or other intravenous fluids to near body temperature, without any adverse affects.

Air Detection Performance of the Level 1 H-1200 Fluid and Blood Warmer

We evaluated the Level 1 H-1200 fluid warmer during simulated conditions of minor to massive air embolism. The fluids we tested were crystalloid and diluted red cells (estimated hematocrit 50%) during gravity and pressure driven flow. The air volumes tested ranged from 1-60 mL for crystalloid and 30-150 mL for red cells. No air was observed distal to the air detector and clamp during all test conditions. The device consistently alarmed and automatically shut off flow. Air was easily purged through the gas vent-filter assembly during simulated air embolism with crystalloid but not with red cell infusion. The use of ultrasonic air detection coupled with automatic shutoff is a significant safety improvement of the Level 1 H-1200 fluid and blood warmer.

Crimean-Congo hemorrhagic fever: experience at a tertiary care hospital in Karachi, Pakistan

Crimean-Congo hemorrhagic fever (CCHF) is endemic in certain rural areas of Pakistan. Since the discovery of CCHF virus (CCHFV) in the country in the 1960s, there have been 13 outbreaks in addition to sporadic cases. An outbreak during 2000 coincided with the movement of sacrificial animals from rural to urban areas for the festival of Eid-ul-Azha. Diagnosis was suspected in patients with fever and thrombocytopenia, and confirmed retrospectively using immunoassays and reverse transcriptase-PCR. Patients were given platelet, plasma and red cell infusions. Management varied due to unfamiliarity with the condition and its treatment, lack of availability of diagnostic laboratory tests and limited supply of ribavirin. Inadequate antiviral treatment and late presentation probably contributed to the death of six of the eight patients. Renal failure, disseminated intravascular coagulation and persistent high-grade fever were associated with mortality. The nucleotide sequence of the small genomic RNA segment of the CCHFV isolated in this outbreak was found to be very closely related to the CCHFV strains previously isolated in Pakistan.

An algorithm to reduce allogenic red blood cell transfusions for major orthopedic surgery

In a previous prospective study, we confirmed that transfusion-related immunosuppression predisposes to postoperative infections, impairs the postoperative healing of wound and thereby prolongs hospitalization. This increases the well-known risks, such as transmission of infection or transfusion reactions, and has obliged us to revise our transfusion guidelines. We used a relational database containing information about 28,861 orthopedic surgery patients was used to determine when and how to improve these guidelines for transfusions. The survey showed the circumstances surrounding a high incidence of allogenic red cell infusions: failure to follow the guidelines, the preoperative use of nonselective NSAIDs, low preoperative Hb level, failure to retrieve blood, and high cut-off values for allogenic red cell transfusion. The first step was to determine the Hb level before giving red cell infusions and ensure compliance with predefined cut-off values. Subsequent measures included: use of COX 2-selective NSAIDs alone in the perioperative period; erythropoietin and iron therapy when the Hb level fell below 13 g/dL; use of cell salvage during and after surgery; administration of aprotinin to patients expected to have a high blood loss. The type of anesthesia had no blood-sparing effect. Although these steps can not be regarded as a new approach, we show that by following a strict rules with appropriate steps and in a concerted fashion, the use of allogenic red blood cells was reduced by 80%. Moreover, the amount of blood saved had other effects--e.g., the incidence of deep wound infections was reduced by 40%. The outcome is described in an algorithm summarizing the steps in a comprehensive perioperative diagram for giving blood.

Frequency and risk factors in bronchopulmonary dysplasia in a cohort of very low birth weight infants.

Frequency and perinatal risk factors in bronchopulmonary dysplasia (BPD) were retrospectively evaluated in a cohort of 242 infants with birth weights less than 1501 g born in one hospital in 1990-1994. At 28 days' postnatal age, 30.7% (59/192) of the infants alive received oxygen supplementation and showed typical radiological changes in chest X-rays. At 36 weeks' corrected gestation, 13.0% (24/184) of the survivors fulfilled these criteria. In multivariate analysis, low birth weight and gestational age, male sex, packed red cell infusions and long duration of ventilator therapy were correlated with an increased risk of BPD at 28 days' postnatal age. Only 49% of the infants with BPD had had respiratory distress syndrome, and 49% of them recovered from BPD by 36 weeks' corrected gestational age. Preeclampsia, low birth weight, rapid birth weight recovery, packed red cell infusions, long duration of ventilator therapy, patent ductus arteriosus and hyperoxia were associated with BPD beyond 36 weeks' corrected gestation. No infant born small for gestational age recovered from BPD before 36 weeks' corrected gestation. The frequency of BPD at 28 days' postnatal age seems to be increasing, but half of the patients recover before term. Factors other than respiratory distress syndrome, especially small birth weight, early weight gain and possibly intrauterine growth retardation are becoming more important risk factors of BPD beyond 36 weeks' corrected gestation.

Thrombelastogram reveals hypercoagulability after administration of gelatin solution

We have compared the effects of gelatin, low molecular weight hydroxyethyl starch (HES) or albumin on tests of haemostasis and on the thrombelastogram in 42 ASA I patients undergoing total hip or knee replacement. Patients were allocated randomly to receive one of the three blood substitutes to obtain moderate intraoperative haemodilution. Blood loss and packed red cell infusion was the same in each group. A greater amount of gelatin was given (1.5 times the measured blood loss) because of its shorter half-life. There was a statistically significant but clinically negligible decrease in platelets count, prothrombin time and fibrinogen, and an increase in bleeding time in all groups. Platelets were slightly but significantly lower after HES. Haemodilution was comparable between groups. TEG showed a state of hypercoagulability in the gelatin group with a significant decrease in r, r + k and an increase in alpha angle.

In vivo demonstration of red cell-endothelial interaction, sickling and altered microvascular response to oxygen in the sickle transgenic mouse.

Intravascular sickling, red cell-endothelium interaction, and altered microvascular responses have been suggested to contribute to the pathophysiology of human sickle cell disease, but have never been demonstrated under in vivo flow. To address this issue, we have examined a transgenic mouse line, alphaHbetaSbetaS-Antilles [betaMDD] which has a combined high (78%) expression of beta S and beta S-Antilles globins. In vivo microcirculatory studies using the cremaster muscle preparation showed adhesion of red cells, restricted to postcapillary venules, in transgenic mice but not in control mice. Electron microscopy revealed distinct contacts between the red cell membrane and the endothelium surface. Some red cells exhibiting sickling were regularly observed in the venular flow. Infusion of transgenic mouse red cells into the ex vivo mesocecum vasculature also showed adhesion of mouse red cells exclusively in venules. Under resting conditions (pO2, 15-20 mmHg), there were no differences in the cremaster microvascular diameters of control and transgenic mice; however, transgenic mice showed a drastic reduction in microvascular red cell velocities (Vrbc) with maximal Vrbc decrease (> 60%) occurring in venules, the sites of red cell adhesion and sickling. Local, transient hyperoxia (pO2, 150 mmHg) resulted in striking differences between control and transgenic mice. In controls, oxygen caused a 69% arteriolar constriction, accompanied by 75% reduction in Vrbc. In contrast, in transgenic mice, hyperoxia resulted in only 8% decrease in the arteriolar diameter and in 68% increase in VrBC; the latter is probably due to an improved flow behavior of red cells as a consequence of unsickling. In summary, the high expression of human sickle hemoglobin in the mouse results not only in intravascular sickling but also red cell-endothelium interaction. The altered microvascular response to oxygen could be secondary to blood rheological changes, although possible intrinsic differences in the endothelial cell/vascular smooth muscle function in the transgenic mouse may also contribute. These sickle transgenic mice could serve as a useful model to investigate vasoocclusive mechanisms, as well as to test potential therapies.

Recombinant interferon alpha 2a, thymopentin and low doses of cytosine arabinoside for the treatment of myelodysplastic syndromes: a pilot study.

Eighteen patients (pts) with myelodysplastic syndrome (MDS) were treated with thymopentin (TP) (50 mg subcutaneously for 5 days) and recombinant interferon alpha 2a (rIFN alpha 2a) (3 MU/m2 subcutaneously on the sixth day); the courses were delivered every week. Moreover those pts with > or = 10% blasts in the bone marrow were additionally treated with low dose cytosine arabinoside (LDARAc) (20 mg standard dose, subcutaneously, twice a day for seven days every four weeks). Sixteen pts were finally assessable for response. Seven pts (44%) were classified as good responders, 5 (31%) had a PR; the overall response rate (GR+PR) was 75%. Two pts (12.5%) showed stable disease and the 2 remaining (12.5%) had progressive disease. Six pts with an initial moderate anemia never required supportive care before and during the therapy; in contrast to 10 pts who were transfusion-dependent. After six months of therapy 2 pts decreased their transfusional needs by 50% (1 of them did not receive any transfusion over the following six months of therapy); 2 pts needed no packed red cell infusions and 1 pt decreased his transfusional support by 75%. Five pts kept an unchanged supportive care load. The overall median survival was 12.5 months. Therapy was generally well tolerated with acceptable compliance; the most frequently recorded side effects were neutropenia and thrombocytopenia grade 2-3 among the group receiving LDARAc. However no life-threatening infectious episodes or bleeding were observed. TP, rIFN alpha 2a and LDARAc can be safely administered on an outpatient basis to MDS pts and appears to have significant activity.(ABSTRACT TRUNCATED AT 250 WORDS)

In Vitro and In Vivo Evaluation of an Electromechanical Blood Infusion Pump

To evaluate the suitability of the LifeCare Model 4 electromechanical infusion pump and cassette (Abbott Laboratories) for red cell infusions, both in vitro markers of red cell damage (plasma hemoglobin, percentage of hemolysis, and osmotic fragility) and in vivo51Cr-labeled red cell survival and half the disappearance time (T½) of packed red cells and other red cell components (whole blood, AS-1 -preserved red cells, and frozen-thawed deglycerolized red cells) passed through the pump were evaluated. No statistically significant differences were found in the in vitro assays between gravity-filtered control red cell-containing products and those blood products pumped at either 50 or 200 mL per hour after either short- or long-term storage. Similarly, no statistically significant differences (paired t test) were observed between pumped and control red cells in terms of either 24-hour in vivo survival or T½ between the pumped or control cells, using a crossover study in which individual subjects (n = 5) served as their own controls. The current Abbott LifeCare Model 4 electromechanical infusion pump and cassette thus appears suitable for the administration of red blood cells at a constant rate of infusion.