Current good manufacturing practices for transfusion medicine

Transfusion medicine is most tightly controlled in the US by CGMPs that are written as regulations, guidances, and quality management documents. Because the US regulatory scheme requires that each unit of human blood donated for transfusion (and other purposes) be documented from the moment of donor registration until the last component of that donation is finally disposed of, there is precious little that remains solely within the discretion of the treating physician who orders transfusions for her or his patients. An additional complication for transfusion medicine specialists is that the search for the requirements must extend to all possible areas of information, including the possibly unexpected source within the private sector.     

Red blood cell transfusion practices in patients undergoing orthopedic surgery: a multi-institutional analysis

This retrospective review analyzed and compared transfusion practices in patients undergoing orthopedic surgery in five Massachusetts hospitals with current practice guidelines; opportunities for improvement were identified. Patient-specific clinical information and data about transfusion practices were obtained from the medical records of 384 Medicare patients undergoing orthopedic surgery between January 1992 and December 1993. The number of patients who donated autologous blood preoperatively differed significantly among hospitals as did the number of autologous units that were unused. The number of blood units transfused at each transfusion event also differed significantly; some surgeons transfused > or =2 units in the majority of their patients, while others transfused 1 unit at a time. This variation in practice was not explained by differences in patients' clinical status. The mean pretransfusion hematocrit was higher for autologous versus allogeneic blood, suggesting more liberal criteria to transfuse autologous blood. Nearly half of all transfusion events were determined to have been potentially avoidable. Avoidable transfusions were also three to seven times more likely with autologous than with allogeneic blood. Significant inter-hospital differences existed in the number of elective surgery patients exposed to allogeneic blood. The major determinant of allogeneic blood use in these patients was the availability of autologous blood. Each additional autologous blood unit available decreased the odds of allogeneic blood exposure twofold. Differences in intraoperative and postoperative blood salvage use also were noted. These findings indicate that significant variations in practice exist. Comparative data enabled hospitals to identify and target specific areas for improvement.     

The relationship of packed cell transfusion to red blood cell deformability in systemic inflammatory response syndrome patients

Minor traumatic brain injury accounts for the majority of the one million head trauma attendances at A&E departments in the United Kingdom. Guidelines have been established listing criteria for skull films, admission to hospital, computed tomography, and neurosurgical consultation. These are currently undergoing revision and were the subject of a satellite symposium to the J Douglas Miller memorial meeting held in October 1996 in Edinburgh. In the East Anglia Region the current guidelines have been issued as memo-cards for A&E officers. The aim of admission is to observe for deterioration, predominantly caused by intracranial haematomas. The indicators for the development of such lesions are an impaired level of consciousness and presence of a skull fracture. Such patients should therefore undergo regular and frequent neurological observations, and be admitted for at least 12 hours. Following discharge, routine follow up should be considered to identify and treat patients with postconcussion symptoms and signs. The possible way forward for the management of these patients is adopting a greater emphasis on preventative aspects, and establishing, implementing, and auditing evidence based guidelines. Improved teaching in the form of formal induction seminars and computerised teaching aids is required, and a better understanding of the aetiology and treatment of the postconcussion syndrome.     

Gender-related variation in transfusion practices

Upper airway symptoms in workers employed in the manufacture of wood products using ultraviolet radiation curing or acid curing of surface coating have been reported. In this study, workers were divided into groups according to exposure: (1) UV-surface coating line, (2) acid curing surface coating line, (3) finishing processes of UV-cured acrylate coated products, (4) finishing processes of of both UV- and acid cured coated wood products, and (5) control group. The workers were examined with nasal lavage in order to investigate inflammatory signs (ECP, tryptase, albumin and microscopy with cell differential counting). UV-line workers and finishers had significantly increased levels of ECP in nasal lavage. There was a positive correlation between exposure time and ECP and albumin levels. Workers with general nasal complaints and atopics had increased levels of ECP. In this study there were findings indicating an inflammatory process in the nasal mucosa in workers exposed to UV radiation curing multifunctional acrylate coatings. The findings indicate an unspecific inflammation and, therefore, a correlation between occupational exposure to acrylate coatings and nasal inflammation seems probable.     

Review of autologous and allogeneic blood transfusion practices in patients undergoing radical hysterectomy

We investigated the short-term recuperation of bone mass during skeletal reloading after a period of unloading in young rats. One hind limb of 4-week-old rats was either unloaded irreversibly by sciatic neurectomy, or unloaded reversibly by external fixation. Other animals were sham-operated. After 9 days, the fixation-unloaded limbs were reloaded for 1-3 weeks and were compared with the hind limbs of age-matched unloaded (neurectomized) and sham-operated controls. Cortical and cancellous bone mass was measured using ashing and histomorphometry. Cortical bone mass (expressed as femoral dry and ash weight and tibial cortical bone area) was reduced in both unloaded groups and was accompanied by production of hypomineralized bone, as shown by a reduction in the percent ash of the dry weight. Cancellous bone mass (expressed as bone area and surface at the tibial metaphysis) was also reduced in both unloaded groups. Cortical bone mass deficit was greater in the fixation group than in the neurectomy group. Thereafter it increased in the neurectomy group despite a normal longitudinal growth rate, but returned to age-matched values in the reloaded group by 3 weeks. The changes in tibial cancellous bone mass were more pronounced but followed a similar pattern and normalized by 2 weeks. These data demonstrate that total unloading produced by external fixation causes a greater degree of bone mass deficit than partial unloading (produced by neurectomy); the rate of bone loss during unloading in the rat hind limb is more rapid than its recovery during reloading; and cancellous bone recuperates during the reloading phase faster than does cortical bone.     

The hemostatic effect of packed red cell transfusion in patients with anemia

BACKGROUND: The hemostatic effect of platelets has been well established, but the possible role of red cells in hemostasis has not yet been well studied. An evaluation of the hemostatic effect of packed red cell transfusion in patients with chronic anemia was the purpose of this study. STUDY DESIGN AND METHODS: In a prospective study, bleeding time (BT), activated partial thromboplastin time (APTT), and prothrombin time (PT) were measured before and after the transfusion of allogeneic packed red cells in 42 patients with chronic anemia. The results were compared and analyzed. RESULTS: APTT and BT decreased significantly after transfusion, by a mean of 1.3 seconds (p = 0.01) and 2.6 minutes (p < 0.01), respectively. PT did not change significantly after transfusion (p = 0.65). Factors studied (patient's age, sex, and renal function measurements; pretransfusion and posttransfusion hemoglobin levels, platelet counts, and PTs; change in platelet count [delta platelet count] and PT [delta PT] after transfusion) did not independently affect the change in BT (delta BT) or in APTT (delta APTT). The delta BT was not affected by the pretransfusion or posttransfusion levels of APTT or by the delta APTT. The delta APTT was not affected by the pretransfusion or posttransfusion levels of BT or by the delta BT. Diagnosis of malignant or benign diseases was found to affect delta APTT, but not delta BT. Patients with pretransfusion hemoglobin < or = 60 g per L had a 4.07 times greater chance of posttranfusion increase in BT than the patients with hemoglobin > 60 g per L (p = 0.04). CONCLUSION: Red cell transfusion might decrease the APTT and BT in some anemic patients, though the actual cause of the decrease was not determined in the present study.     

The mechanism of chlorpromazine-induced red blood cell swelling

1. Chlorpromazine (CPZ)-induced red blood cell (RBC) swelling was investigated by determination of electrolyte, mean cell volume (MCV) and water content changes in CPZ-treated cells. 2. CPZ-induced RBC swelling is dose-, hematocrit- and pH-dependent, and is associated with a net increase in RBC monovalent cation and Cl- contents. 3. The partition coefficient (Kp) for the CPZ-RBC membrane interaction is pH dependent (Kp = 2500 at pH 7.8; Kp = 840 at pH 6.8). 4. Despite the pH dependence of Kp values an equal number of CPZ molecules is required to induce a 12% increase in MCV at pH 7.8 and 6.8.     

Bone-marrow imaging in pure red blood cell aplasia

Bone-marrow scintigraphy with indium chloride in 111 was performed on a patient with pure red blood cell aplasia before and after successful treatment with immunosuppressive drugs. The return of erythroid precursors to the bone marrow was accompanied by a substantial increase in the marrow uptake of 111In. The distribution of 111In in the posttreatment scan was indistinguishable from that of 52Fe. These results indicate that indium chloride in 111 is a useful agent for the delineation of erythroid cellularity within bone marrow.     

Autologous blood transfusion

Autologous blood transfusion is a procedure in which blood is removed from a donor and returned to his circulation at some later time. Autologous transfusion can be performed in three ways: (1) preoperative blood collection, storage, and retransfusion during surgery; (2) immediate preoperative phlebotomy with subsequent artificial hemodilution and later return of the phlebotomized blood; and (3) intraoperative blood salvage and retransfusion. All three methods of autologous transfusion offer a potentially superior method of blood transfusion which eliminates many of the problems and complications associated with the banking and administration of homologous donor blood.     

Autologous blood transfusion

BACKGROUND: The clinical significance of lymph node involvement along the recurrent laryngeal nerves in cancer of the thoracic esophagus is still controversial. Although these lymph nodes are anatomically located in a well-defined compartment (proximal mesoesophagus), appropriate procedures for dissecting them are not well established. STUDY DESIGN: We retrospectively investigated clinical results over the past 10 years in 276 patients who underwent systematic dissection of cervical, mediastinal, and upper abdominal lymph nodes. We routinely performed the cervical procedure before thoracotomy for total dissection of the proximal mesoesophagus and to minimize the operative risk. RESULTS: All macroscopically recognizable lesions were resected in 94% of the patients. The hospital mortality rate was 2.5%. Recurrent nerve palsy developed in 59 patients, but it was successfully managed without prolonged hoarseness in 50 of them. The recurrent nerve node group was most frequently involved (frequency of 25% in superficial cancer, 57% in non-superficial cancer). Supradiaphragmatic lymph node involvement was limited to the recurrent nerve nodes in 25% of the patients with positive supradiaphragmatic node. The 5-year survival rate in patients with positive recurrent nerve nodes was 34%. CONCLUSIONS: Dissection of the recurrent nerve lymph nodes is essential for curative esophagectomy even in the early phase of cancer invasion. Our cervicothoracic approach for total dissection of the proximal mesoesophagus yielded acceptable outcomes.     

Rabbit red blood cell hexokinase. Purification and properties

Rabbit red blood cell hexokinase (EC 2.7.1.1.) has been purified 300,000-fold by a combination of ion exchange chromatography, affinity chromatography, and preparative polyacrylamide gel electrophoresis. The hexokinase activity has been isolated in 35% yield as a protein that is homogeneous by polyacrylamide and sodium dodecyl sulfate gel electrophoresis. The highest specific activity obtained was 145 units/mg of proteins. The native protein has a molecular weight of 110,000 by gel filtration on Ultrogel AcA 44 and 112,000 by sedimentation velocity on sucrose density gradients. Sodium dodecyl sulfate-polyacrylamide gels gave a molecular weight of 110,000 indicating that hexokinase is a monomer. The enzyme had a pI of 6.20 to 6.30 pH units by isoelectric focusing. The enzyme was specific for Mg . ATP and Mg . ITP as the nucleotide substrates. Several hexokinase with different affinities.     

Static equilibrium configurations of a model red blood cell

The membrane of the red blood cell is modeled as a fluid shell which resists bending and changes in area. The differential equations governing the mechanical equilibrium of such a membrane are derived and axisymmetric solutions are obtained numerically.     

贫血患者红细胞参数检测的参考价值

贫血是指全身循环血液中红细胞总量减少至正常值以下.但由于全身循环血液中红细胞总量的测定技术比较复杂,所以临床上一般指外周血中血红蛋白的浓度低于患者同年龄组、同性别和同地区的正常标准.采用MCV和RDW两项指标对贫血进行新的形态学分类,对贫血的鉴别诊断有一定的参考价值.     

Autologous cord blood transfusion

Pilonidal sinus is an unglamorous surgical condition, often left to juniors, that is difficult to treat. Correct decisions in management may influence the prognosis of the condition by avoiding recurrence and continued sepsis.     

Changing transfusion practices in hip and knee arthroplasty

BACKGROUND: This study was designed to examine changes in perioperative transfusion practices after the introduction of autologous blood conservation strategies into routine clinical practice. STUDY DESIGN AND METHODS: The existing medical records of all patients undergoing total hip or knee arthroplasty at Mayo Clinic in Rochester, MN, who resided in Olmsted County, were reviewed over three periods: 1981-82 (232 procedures), 1987-88 (269 procedures), and 1993-94 (398 procedures). RESULTS: The proportion of patients receiving any perioperative red cell (RBC) units significantly decreased (from 85% in 1981-82 to 65% in 1993-94). The timing of transfusion also changed; the proportion of RBC units transfused in the preoperative or intraoperative periods decreased from 68 percent in 1981-82 to 38 percent in 1993-94, with the balance of RBC units transfused in the postoperative period. Although the number of RBC units utilized per procedure in the intraoperative period significantly decreased, the number of RBC units transfused in the postoperative period significantly increased (from 0.6 +/- 1.0 to 1.1 +/- 1.4 units per procedure in 1981-82 and 1993-94, respectively, p < 0.05). CONCLUSION: Although blood conservation strategies have been successful in reducing RBC transfusion intraoperatively, avoidance of intraoperative transfusion may in some cases postpone, rather than prevent, transfusion.