Community-based cancer screening for underserved women: design and baseline findings from the Breast and Cervical Cancer Intervention Study

BACKGROUND

Underutilization of breast and cervical cancer screening has been observed in many ethnic groups and underserved populations. Effective community-based interventions are needed to eliminate disparities in screening rates and thus to improve prospects for survival.

METHODS

The Breast and Cervical Cancer Intervention Study was a controlled trial of three interventions in the San Francisco Bay Area from 1993 to 1996: (1) community-based lay health worker outreach; (2) clinic-based provider training and reminder system; and (3) patient navigator for follow-up of abnormal screening results. Study design and a description of the interventions are reported along with baseline results of a household survey conducted in four languages among 1599 women, aged 40-75.

RESULTS

Seventy-six percent of women ages 40 and over had had at least one mammogram, and most had had a clinical breast examination (88%) and Pap smear (89%). Rates were significantly lower for non-English-speaking Latinas and Chinese women (56 and 32%, respectively, for mammography), and maintenance screening (three mammograms in the past 5 years) varied from 7% (non-English-speaking Chinese) to 53% (Blacks). Pap smear screening in the past 3 years was low among non-English-speaking Latinas (72%) and markedly lower among non-English-speaking Chinese women (24%). The strongest predictors of screening behavior were having private health insurance and frequent use of medical services. Having a regular clinic and speaking English were also important. Race/ethnicity, education, household income, and employment status were, overall, not significant predictors of screening behavior.

CONCLUSIONS

These baseline results support the importance of cancer screening interventions targeted to persons of foreign origin, particularly those less acculturated.

Surveying Saccharomyces genomes to identify functional elements by comparative DNA sequence analysis

Comparative sequence analysis has facilitated the discovery of protein coding genes and important functional sequences within proteins, but has been less useful for identifying functional sequence elements in nonprotein-coding DNA because the relatively rapid rate of change of nonprotein-coding sequences and the relative simplicity of non-coding regulatory sequence elements necessitates the comparison of sequences of relatively closely related species. We tested the use of comparative DNA sequence analysis to aid identification of promoter regulatory elements, nonprotein-coding RNA genes, and small protein-coding genes by surveying random DNA sequences of several Saccharomyces yeast species, with the goal of learning which species are best suited for comparisons with S. cerevisiae. We also determined the DNA sequence of a few specific promoters and RNA genes of several Saccharomyces species to determine the degree of conservation of known functional elements within the genome. Our results lead us to conclude that comparative DNA sequence analysis will enable identification of functionally conserved elements within the yeast genome, and suggest a path for obtaining this information.

Baseline staging tests in primary breast cancer: a practice guideline

BACKGROUND

Breast cancer develops in over 7000 women each year in Ontario. These patients will all undergo some staging work-up at diagnosis. The Breast Cancer Disease Site Group of the Cancer Care Ontario Practice Guidelines Initiative reviewed the evidence and indications for routine bone scanning, liver ultrasonography and chest radiography in asymptomatic women who have undergone surgery for breast cancer.

METHODS

A systematic review of the published literature was combined with a consensus interpretation of the evidence in the context of conventional practice.

RESULTS

There were 11 studies of bone scanning reported between 1972 and 1980, involving a total of 1307 women; bone scans detected skeletal metastases in 6.8% of those with stage I breast cancer, 8.8% with stage II and 24.5% with stage III. A total of 5407 women participated in 9 studies of bone scanning reported between 1985 and 1995; in these studies, bone scans detected skeletal metastases in only 0.5% of women with stage I disease, 2.4% with stage II and 8.3% with stage III. Among 1625 women in 4 studies of liver ultrasonography reported between 1988 and 1993, hepatic metastases were detected in 0% of patients with stage I disease, 0.4% with stage II and 2.0% with stage III. Among 3884 patients in 2 studies of chest radiography published in 1988 and 1991, lung metastases were detected in 0.1% of those with stage I, 0.2% with stage II and 1.7% with stage III. False-positive rates ranged from 10% to 22% for bone scanning, 33% to 66% for liver ultrasonography and 0% to 23% for chest radiography. The false-negative rate for bone scanning was about 10%.

RECOMMENDATIONS

The following recommendations apply to women with newly diagnosed breast cancer who have undergone surgical resection and who have no symptoms, physical signs or biochemical evidence of metastases. Routine bone scanning, liver ultrasonography and chest radiography are not indicated before surgery. In women with intraductal and pathological stage I tumours, routine bone scanning, liver ultrasonography and chest radiography are not indicated as part of baseline staging. In women who have pathological stage II tumours, a postoperative bone scan is recommended as part of baseline staging. Routine liver ultrasonography and chest radiography are not indicated in this group but could be considered for patients with 4 or more positive lymph nodes. In women with pathological stage III tumours, bone scanning, liver ultrasonography and chest radiography are recommended postoperatively as part of baseline staging. In women for whom treatment options are restricted to tamoxifen or hormone therapy, or for whom no further treatment is indicated because of age or other factors, routine bone scanning, liver ultrasonography and chest radiography are not indicated as part of baseline staging.

Intracranial pressure accommodation is impaired by blocking pathways leading to extracranial lymphatics

Tracer studies indicate that cerebrospinal fluid (CSF) transport can occur through the cribriform plate into the nasal submucosa, where it is absorbed by cervical lymphatics. We tested the hypothesis that sealing the cribriform plate extracranially would impair the ability of the CSF pressure-regulating systems to compensate for volume infusions. Sheep were challenged with constant flow or constant pressure infusions of artificial CSF into the CSF compartment before and after the nasal mucosal side of the cribriform plate was sealed. With both infusion protocols, the intracranial pressure (ICP) vs. flow rate relationships were shifted significantly to the left when the cribriform plate was blocked. This indicated that obstruction of the cribriform plate reduced CSF clearance. Sham surgical procedures had no significant effects. Estimates of the proportional flow through cribriform and noncribriform routes suggested that cranial CSF absorption occurred primarily through the cribriform plate at low ICPs. Additional drainage sites (arachnoid villi or other lymphatic pathways) appeared to be recruited only when intracranial pressures were elevated. These data challenge the conventional view that CSF is absorbed principally via arachnoid villi and provide further support for the existence of several anatomically distinct cranial CSF transport pathways.

Systematic overview of the evidence for brachytherapy in clinically localized prostate cancer

BACKGROUND

Brachytherapy (permanent implantation of radioactive seeds) has emerged as an alternative to existing standard therapy with radical prostatectomy or external beam radiotherapy in the treatment of clinically localized (T1 and T2) prostate cancer. The Genitourinary Cancer Disease Site Group of the Cancer Care Ontario Practice Guidelines Initiative examined the role of brachytherapy in treating clinically localized prostate cancer.

METHODS

A systematic review of articles published from 1988 to April 1999, retrieved through a search of MEDLINE and CANCERLIT databases, was combined with a consensus interpretation of the evidence in the context of conventional practice.

RESULTS

Although there were no randomized trials comparing brachytherapy with standard treatment, evidence was available from 13 case series and 3 cohort studies. Rates of freedom from biochemical failure (biochemically no evidence of disease [bNED]) varied considerably from one series to another and were highly dependent on tumour stage, grade and pretreatment serum prostate-specific antigen (PSA) levels. Results in patients with favourable tumours (T1 or T2 tumour, Gleason score of 6 or lower, serum PSA level of 10 ng/mL [microgram/L] or less) were comparable to those in patients undergoing radical prostatectomy. Acute urinary retention was reported in 1%-14% of patients. Long-term sequelae occurred in less than 5% of patients and included urinary incontinence, cystitis, urethral strictures and proctitis. Sexual potency was maintained after implantation in 86%-96% of patients.

INTERPRETATION

At present, there is insufficient evidence to recommend the use of brachytherapy over current standard therapy for localized prostate cancer. Brachytherapy using transrectal ultrasound guidance for seed implantation is promising in terms of freedom from biochemical failure in selected patients with early-stage prostate cancer. Brachytherapy is currently available outside of clinical trials, but whenever possible patients should be asked to participate in randomized trials comparing brachytherapy and current standard therapy. Brachytherapy should be available to selected patients (those with T1c or T2a tumours, a Gleason score of 6 or lower and a serum PSA level of 10 micrograms/L or less), after discussion of the available data and potential adverse effects.

Mind-Mapped Care Plans

Nursing care plans have helped students learn problem solving for nursing practice, but creativity and the interrelationship of patient problems are not stimulated by their linear nature. Joining mind mapping with care planning forces connections, engages whole brain thinking, and stimulates creativity. The authors describe mind mapping, infusion of mind-mapped care plans into the curriculum, the teaching/learning process of mapped care plans, and the positive outcomes of mind mapping nursing care plans.

Problems with the sickness impact profile: a theoretically based analysis and a proposal for a new method of implementation and scoring

The Sickness Impact Profile (SIP) is one of the most widely used health status measures, but there are problems with the measure that lead to inconsistent and illogical scores. There are many desirable features to the SIP development methodology in that it is based on a good range of items and the item weightings are valuable. The current method of scoring the SIP is the use of a summated total and was selected based on limited empirical evidence. However, in this paper we argue that there are problems with the SIP because the current empirically derived method of scoring is incompatible with both the underlying theoretical scaling framework (Thurstone scaling) and the nature of the items in the SIP. In addition, the items do not have properties consistent with the scaling methodology. We suggest that it is crucial to take both a theoretical and empirical approach to selecting a scoring method. To examine problems associated with the SIP we explored the underlying scaling methodology and identified the types of items in the SIP. A new method of scoring is proposed that is consistent with the items and scaling in the SIP, namely using the maximum individual weighting from the items that were checked as a category score. This new method of scoring resolves many of the previously observed problems in the SIP. The new method of scoring also presented the opportunity for a new implementation of the SIP that reduces the number of items that most respondents, especially those with severe limitations, would be asked. Without taking a theoretical approach to scoring we suggest that subsequent, empirically based, scale amendments are unlikely to solve the problems. It is proposed that this new method of scoring justifies a thorough empirical investigation.

Fibrinolytic variables in patients with recurrent venous thrombosis: a prospective cohort study

To determine whether fibrinolytic testing predicts recurrent venous thrombosis, we have performed a prospective cohort study in which 303 patients with a first episode of venous thromboembolism underwent comprehensive fibrinolytic testing while receiving oral anticoagulants, and after anticoagulants had been discontinued. They were then followed for up to 3 years for recurrent venous thrombosis. No systematic differences in the levels or activity of type 1 plasminogen activator inhibitor (PAI-1), tissue plasminogen activator (tPA) or euglobulin clot lysis times were detected between patients who did, or did not, suffer recurrent thrombosis. There were also no differences in these variables when patients whose initial thrombosis was idiopathic were compared to patients whose thrombosis occurred in the setting of a known thrombotic risk factor. Based on these results, neither measuring fibrinolytic parameters in patients with venous thromboembolism, nor modification of treatment based on the results of such testing, are justified. Our study also confirms that patients with idiopathic venous thromboembolism have a high risk of recurrence.

A latex D-dimer reliably excludes venous thromboembolism

BACKGROUND

D-Dimer, a cross-linked fibrin degradation product, has a high sensitivity in patients with suspected venous thrombosis. Traditional latex D-dimer assays, however, have not been sufficiently sensitive to exclude venous thromboembolism.

METHODS

To determine the clinical utility of a latex D-dimer assay (MDA D-Dimer; Organon Teknika Corporation, Durham, NC) in patients with suspected venous thromboembolism, we conducted a retrospective cohort study involving 595 unselected patients at 4 tertiary care hospitals. Patients had blood drawn for performance of the D-dimer assay and underwent objective testing for venous thromboembolism. Pretest probability was determined using validated models in 571 patients. Patients were classified as venous thromboembolism positive or negative according to results of objective tests and 3-month follow-up. The sensitivities, specificities, predictive values, and negative likelihood ratios of the assay were calculated for all patients and for subgroups of patients with known cancer or a low, moderate, or high pretest probability of venous thromboembolism.

RESULTS

The prevalence of venous thromboembolism was 19.0% (113/595). Of those who had a pretest probability assessment, 35.9% had a low pretest probability, 49.7% a moderate pretest probability, and 14.4% a high pretest probability. Using a discriminant value of 0.50 microg fibrinogen equivalent units per milliliter, the assay showed an overall sensitivity of 96%, a negative predictive value of 98%, a specificity of 45%, and a negative likelihood ratio of 0.09. In patients with a low or moderate pretest probability, the sensitivity, negative predictive value, and negative likelihood ratio were 97%, 99%, and 0.07, respectively.

CONCLUSIONS

The MDA D-Dimer assay is the first latex agglutination assay with sufficient sensitivity to be clinically useful in the exclusion of venous thromboembolism. A negative result has the potential to be used as the sole test to exclude venous thromboembolism in patients with a low or moderate pretest probability of disease.

Use of a fixed activated partial thromboplastin time ratio to establish a therapeutic range for unfractionated heparin

BACKGROUND

The commonly recommended therapeutic range for patients receiving unfractionated heparin of 1.5 to 2.5 times the control activated partial thromboplastin time (aPTT) is not universally applicable. It has been suggested that the therapeutic range for each aPTT reagent should be based on plasma heparin levels. We sought to identify an aPTT ratio that corresponds to therapeutic anti--factor Xa heparin levels for combinations of several reagents and coagulometers that are commonly used.

METHODS

Citrated plasma was collected from 126 unselected patients receiving unfractionated heparin. Four automated coagulometers and 6 commercial aPTT reagents were used to measure the aPTT. Plasma anti--factor Xa levels were measured by means of a commercially available assay. The relationship between the aPTT results and anti-factor Xa heparin levels for each reagent-coagulometer combination was determined by linear regression analysis, and the aPTT results corresponding to therapeutic anti--factor Xa heparin levels were calculated.

RESULTS

For all reagent-coagulometer combinations studied, an aPTT ratio of 1.5 resulted in anti--factor Xa heparin levels considerably below the lower limit of the therapeutic range. When the aPTT was performed on any of the coagulometers assessed with the use of Actin (Dade Diagnostics, Aguada, Puerto Rico) and IL Test (Instrumentation Laboratories, Fisher Scientific, Unionville, Ontario) reagents, aPTT ratios necessary to achieve therapeutic anti--factor Xa heparin levels approximated 2.0 to 3.5.

CONCLUSION

For laboratories that cannot perform heparin levels, the use of less responsive reagents and any of the coagulometers studied, along with target aPTT ratio between 2.0 and 3.5, appears to be a reasonable alternative.

Surveillance programs for early stage non-seminomatous testicular cancer: a practice guideline

BACKGROUND AND PURPOSE

To identify an appropriate surveillance program for men with clinical stage I non-seminomatous germ cell tumors of the testis (NSGCT).

MATERIALS AND METHODS

A systematic review of the published literature was combined with a consensus process, around the interpretation of the evidence in the context of conventional practice, to develop an evidence-based practice guideline.

RESULTS

No randomized controlled trials (RCTs) comparing surveillance schedules were found, but data from 12 case series and one RCT which compared radiotherapy with surveillance were reviewed. Variations in the schedules were not associated with observed variations in relapse, salvage, or survival rates.

CONCLUSIONS

Men with clinical stage I testicular cancer, as defined by a normal physical examination, normal radiological scans (computed tomography [CT]) and serum markers (alpha-fetoprotein [AFP] and beta-subunit of human chorionic gonadotropin (betaHCG) which are normal or fall within normal limits during their expected half-lives, are eligible for surveillance. A recommended surveillance schedule is as follows: 1) Physical examination, blood serum marker tests (AFP and HCG), and chest x-rays should be conducted every month in the first year, every 2 months in the second year, every 3 months in the third year, and every 6 months in the fourth and fifth years; and 2) CT scans of the abdomen and pelvis should be conducted every 3 months in the first year, every 4 to 6 months in the second year and every 6 months in the third year, and once a year in the fourth and fifth year.

Increasing galactose consumption by Saccharomyces cerevisiae through metabolic engineering of the GAL gene regulatory network

Increasing the flux through central carbon metabolism is difficult because of rigidity in regulatory structures, at both the genetic and the enzymatic levels. Here we describe metabolic engineering of a regulatory network to obtain a balanced increase in the activity of all the enzymes in the pathway, and ultimately, increasing metabolic flux through the pathway of interest. By manipulating the GAL gene regulatory network of Saccharomyces cerevisiae, which is a tightly regulated system, we produced prototroph mutant strains, which increased the flux through the galactose utilization pathway by eliminating three known negative regulators of the GAL system: Gal6, Gal80, and Mig1. This led to a 41% increase in flux through the galactose utilization pathway compared with the wild-type strain. This is of significant interest within the field of biotechnology since galactose is present in many industrial media. The improved galactose consumption of the gal mutants did not favor biomass formation, but rather caused excessive respiro-fermentative metabolism, with the ethanol production rate increasing linearly with glycolytic flux.

The yeast genome: on the road to the Golden Age

Having the complete genome sequence of Saccharomyces cerevisiae makes us aware of the ultimate goal of yeast molecular biology: the 'solution' of the cell, that is, an understanding of the function of all approximately 6000 proteins (and a few RNAs) and how they interact with each other and the environment. The recent development of 'genomic' approaches for studying gene function makes this goal seem reachable in the foreseeable future. When this is accomplished, we will have entered a Golden Age, when we will have the information necessary for designing truly incisive experiments to reveal biological function.

Non-penetrating chest blows and sudden death in the young

Sudden death in the young after low energy anterior chest wall impact is an under-recognised phenomenon in this country. Review of the literature yields several American references to commotio cordis, mainly in the context of sporting events. Two cases are reported of sudden death in young men as a result of blunt impact anterior chest wall trauma. It is suggested that these cases draw attention to a lethal condition of which many practitioners are unaware.

Alterations in the gene expression profile of MCF-7 breast tumor cells in response to c-Jun

MCF7 breast tumor cells overexpressing human c-Jun exhibit a transformed phenotype characterized not only by increased tumorigenicity but also by enhanced motility and invasion. The cellular phenotypic response to c-Jun overexpression is likely due, at least in part, to altered patterns of gene expression. In order to begin to understand the complexities by which elevated production of c-Jun alters the state of the cell, we have profiled the expression of 588 different genes by comparative hybridization. By using this approach, we have identified a total of 21 upregulated or downregulated gene targets responsive to c-Jun overexpression. Interestingly, 8 of these genes have been previously found associated with c-Jun or AP-1 activity and therefore provide internal validation for this approach to target gene discovery. The remaining 13 genes represent potential new c-Jun regulated target genes. Genomic sequence information was available for 15 of the 21 genes identified in this screen. Analysis of these genomic sequences revealed the presence of AP-1 or AP-1-like sequences in 12 of the 15 genes examined. Consistent with a direct mechanism of target regulation by c-Jun, gel shift analysis of selected AP-1-containing promoter regions revealed elevated and specific binding by proteins present in nuclear extracts of c-Jun expressing MCF7 cells.

A child with ALL and ETV6/AML1 fusion on a chromosome 12 due to an insertion of AML1 and loss of ETV6 from the homolog involved in a t(12;15)(p13;q15)

A 4-year-old boy was found to have acute lymphoblastic leukemia characterized by a t(12;15)(p13;q15). FISH investigation using a TEL(ETV6)/AML1 probe detected a fusion signal in 98% of the interphase cells. Sequential FISH on a G-banded slide showed a fusion signal on an apparently normal chromosome 12 and AML1 signals on chromosomes 21. The ETV6 was deleted from the chromosome 12 involved in the t(12;15). These results are best explained as an insertion of AML1 into TEL on one chromosome arm 12p and loss of ETV6 from the chromosome 12 involved in the t(12;15).

One program's experience of OSCE vs. written board certification results: a pilot study

The objective structured clinical examination (OSCE) has been the focus of a lot debate with respect to reliability and validity. Much of the controversy surrounding these components lies in a lack of comparison with a "gold standard." Further work is needed to improve the evaluation of clinical skills to the point that a gold standard can truly be said to exist.

Training residents for community psychiatric practice: the resident perspective

OBJECTIVE

To capture the views and experiences of psychiatry residents in 5 Canadian training programs with respect to community psychiatric training.

METHOD

We sent a questionnaire regarding respondent demography, career interests, and community psychiatry training experiences to psychiatry residents at 5 training programs in Ontario. We undertook descriptive analyses and frequency comparisons on the returned data.

RESULTS

The overall response rate was 48%, with considerable variation between programs. With respect to career planning, respondents indicated highest interest in urban hospital-based practice. An interest in additional community psychiatry training was, however, expressed, particularly by junior residents. Residents' suggestions for improving community psychiatry training included better promotion of training opportunities, improved quality of supervision in community settings, and more didactic teaching.

CONCLUSION

Psychiatry residents are obtaining training experiences in community psychiatry, but objectives and guidelines are quite variable, as is reflected in their understanding of the definition of "community psychiatry." Residents' career paths are still focused on urban hospital-based practice or solo private practice, which likely reflects their prevalent training experiences. There is, however, interest in community psychiatry training. Junior residents may be more open to this type of practice, and curricula should allow more exposure to community psychiatry at this stage of training.

A survey of aPTT reporting in Canadian medical laboratories. The need for increased standardization. Thrombosis Interest Group of Canada

A survey of all licensed medical laboratories performing activated partial thromboplastin time (aPTT) testing in Canada was undertaken; the response rate was 50.7%. Preanalytic phase of testing seemed generally satisfactory, although 46% of laboratories were still using 3.8% or a 129-mmol/L concentration of citrate, and only 59% of institutions routinely performed testing to verify the platelet-poor status of the plasma used for aPTT testing. There were also concerns relating to the speed and duration of centrifugation for specimen preparation. While more than 67% of institutions had established an individual therapeutic range for aPTT testing, only 47% of laboratories verified this range with heparinized samples. Approximately 67% of the institutions that had verified the range had done this by spiking heparin concentrations into pooled plasma rather than using ex vivo specimens from patients receiving heparin therapy. There seemed to be a need for increased education about circumstances under which the therapeutic range should be rechecked and current standards for screening for the lupus anticoagulant. More than 71% of Canadian institutions surveyed used low-molecular-weight heparin, which may obviate many of the issues surrounding aPTT testing. Overall performance as documented by survey results seemed similar to that reported for the United States and Australasia.

The effects of hormone replacement therapy on thrombin generation, fibrinolysis inhibition, and resistance to activated protein C: prospective cohort study and review of literature

Recent studies have found that hormone replacement therapy (HRT) is associated with a two- to fourfold increased risk of venous thromboembolism, but the thrombogenic mechanism of HRT remains unclear. To investigate whether HRT use induces a procoagulant state, we undertook a prospective cohort study in postmenopausal women to investigate the effects of 3 months of treatment with oral HRT (conjugated equine estrogen 0.625 mg daily and medroxyprogesterone 2.5 mg daily) on markers of thrombin generation (prothrombin fragment 1+2, thrombin-antithrombin complexes), fibrinolytic potential (plasminogen activator inhibitor-1 (PAI-1) activity), and activated protein C (APC) resistance. In addition, we reviewed the literature for studies investigating the effects of HRT on markers of thrombin generation and fibrinolytic potential. In 12 patients who received HRT for a mean of 3.8 months, there was no significant effect of HRT on levels of F1+2, thrombin-antithrombin complexes, or the APC ratio. HRT use had the greatest effect on PAI-1 activity (mean difference = -3.75 UI/mL; 95% confidence interval: - 8.9, 1.1) compared to other coagulation parameters, but this did not attain statistical significance (p = 0.12). In the literature review, the effects of HRT on markers of thrombin generation were inconsistent across studies. There was a consistent pattern of increased fibrinolytic potential with HRT use associated with one marker (PAI-1), but not with another marker (tissue plasminogen activator antigen). We conclude that there is a lack of consistent evidence that the increased risk of venous thromboembolism associated with HRT use is due to a procoagulant state related to increased thrombin generation, decreased fibrinolytic potential, or acquired APC resistance.

Relationship between pericardial pressure and lymphatic pericardial fluid transport in sheep

We investigated the relationship between pericardial pressure and the volumetric lymphatic clearance rate of pericardial fluid in sheep. A single catheter perfusion system was established to deliver tracer to the pericardial cavity and control pericardial pressure. In addition, catheters were placed into the thoracic duct and into the jugular vein at the base of the neck. (125)I-human serum albumin (HSA) was administered into the pericardial perfusate to serve as the lymph flow marker and its concentration monitored in the effluent from the outflow end of the perfusion system. (131)I-HSA was injected intravenously to permit calculation of plasma tracer loss and tracer recirculation into lymphatics. From mass balance equations, estimates of total pericardial clearance into lymphatics increased significantly as pericardial pressures were elevated in 2. 5 cm H(2)O increments from 2.5 to 12.5 cm H(2)O (P = 0.018). Pericardial lymph transport ranged from 0.89 +/- 0.10 to 3.09 +/- 0. 66 ml/h at 2.5 and 12.5 cm H(2)O pericardial pressure, respectively. The majority of transport occurred through mediastinal vessels with a small proportion (10.3 to 23.9%) being cleared into lymphatics leading to the thoracic duct. We conclude that lymphatic pericardial fluid transport increases approximately 3.5-fold over a pericardial pressure range that encompasses the transition between the shallow and steep portions of the pericardial pressure-volume relationship.

Hydroxyethylstarch sedimentation by gravity ex vivo for red cell reduction of granulocyte apheresis components

BACKGROUND

When selecting only leukocyte compatible donors, the requirement of ABO compatibility limits the investigation and application of granulocyte transfusion therapy by reducing the pool of potential donors. Ex vivo hetastarch (HES) sedimentation was evaluated as a method of red blood cell (RBC) reduction of granulocyte components. The objective was to determine if this procedure consistently resulted in reduction of component packed RBC (PRBC) volume to < 5 ml, the range acceptable for infusion of ABO incompatible blood components based on guidelines set forth by the American Association of Blood Banks (AABB).

STUDY DESIGN AND METHODS

HLA-matched, ABO-compatible sibling marrow donors were selected to donate granulocyte components, which were transfused into the allogeneic bone marrow transplant (BMT) recipient as prophylaxis against infection. Three granulocyte components were collected from each of 5 donors receiving G-CSF (daily x 5). Leukapheresis (LA) began 1 day after the first G-CSF dose (Day 1), and was repeated on Days 3 and 5. LA were performed using a continuous-flow blood cell separator, with 7L blood processed during each procedure. RBC sedimentation was facilitated by administration of a 6% HES solution to the donor line. The 5 granulocyte components collected on Day 1 were not manipulated after collection. The 10 components collected on Days 3 and 5 were manipulated by ex vivo gravity sedimentation for 60 minutes followed by transfer of the buffy coat (red cell poor [RCP] fraction) to a transfer bag with residual RBCs retained in the collection bag (red cell rich [RCR] fraction). The PRBC volume and cellular composition of the components and fractions were determined.

RESULTS

When data for the 10 manipulated components were combined, the fraction of the components with < 5 ml PRBC was 0.4 in the RCP and 0.1 in the RCR fractions. All unmanipulated components contained > 5 ml PRBC. The mean PRBC volume (ml) of the RCP and RCR fractions were 6.3 and 16.4, respectively (P = .06). The mean number of RBC (x10(11)) in the RCP and the RCR fractions were .41 and 1.73, respectively (P = .03). The average proportion of cells in the manipulated components lost to the RCR fraction was 19.2% of granulocytes and 18.6% of platelets.

CONCLUSION

Ex vivo HES sedimentation, as performed, significantly reduced the number of RBCs from granulocyte components, but did not consistently result in PRBC volumes in the RCP fraction within the range acceptable for infusion of ABO incompatible blood components based on the AABB guidelines. Moreover, significant numbers of granulocytes were lost to the RCR fraction.