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Background

Whole blood donation is generally considered to be a safe procedure, but occasionally adverse reactions of varying severity may occur during or at the end of the collection. The aim of the study was to estimate the frequency and type of adverse events occurring during blood donation and to assess the practices which would help to minimise them.

Materials and methods

This retrospective single-centre study was conducted from June 2007 to November 2009 at a regional blood transfusion centre. All whole blood donations made at the centre were analysed. All adverse events occurring during or at the end of donation were noted using a standardised format.

Results

Overall 113 adverse events were reported in relation to 19,045 donations, resulting in an overall adverse event rate of 0.6%, that is, an incidence of 1 in every 166 donations. Presyncopal symptoms, in other words vasovagal reactions of mild intensity, were the most commonly observed adverse reactions and accounted for approximately 70% of all adverse reactions noted.

Conclusions

Only 0.6% of blood donations were complicated by adverse events and most of these events were presyncopal symptoms. Our study reinforces the fact that blood donation is a very safe procedure which could be made even more event-free by following certain friendly, reassuring and tactful practices.  相似文献   
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Anaemia and RBC (red blood cell) transfusion may be associated with worse clinical outcomes, especially with longer blood storage duration prior to transfusion. The mechanisms underlying these harmful effects are unknown. RBCs have been proposed to buffer plasma S1P (sphingosine 1-phosphate), a lysophospholipid essential for the maintenance of endothelial integrity and important in the regulation of haematopoietic cell trafficking. The present study examined the effect of anaemia, RBC transfusion and RBC storage duration on plasma S1P levels. Plasma S1P from 30 individuals demonstrated a linear correlation with Hct (haematocrit; R2 = 0.51, P < 0.001) with no evidence for a plateau at Hct values as low as 19%. RBC transfusion in 23 anaemic patients with baseline mean Hct of 22.2 ± 0.34% (value is the mean ± S.D.) increased Hct to 28.3 ± 0.6% at 72 h. Despite an Hct increase, RBC transfusion failed to elevate plasma S1P consistently. A trend towards an inverse correlation was observed between RBC storage duration and the post-transfusion increase in plasma S1P. After 30 days of storage, RBC S1P decreased to 19% of that observed in fresh (3-7-day-old) RBC segments. RBC membranes contain low levels of both S1P phosphatase and S1P lyase activities that may account for the decline in S1P levels with storage. Our results support a role for RBCs in buffering plasma S1P and identify a disturbance in the capacity after transfusion. Changes in S1P content may contribute to an RBC storage lesion. Further studies should investigate the clinical significance of alterations in circulating S1P levels and the potential value of enriching stored RBCs with S1P.  相似文献   
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Ureaplasma urealyticum genital infection may lead to severe clinical implications if left undiagnosed and untreated. The present study was conducted to evaluate the diagnostic efficiency of a polymerase chain reaction (PCR) assay and to determine the prevalence of U. urealyticum in Indian adults with symptoms of genital discharge. Cervical swabs, vaginal swabs and male urethral swabs from 100 patients attending an sexually transmitted disease clinic at a tertiary care hospital in Delhi were screened prospectively for infection with U. urealyticum. The prevalence of U. urealyticum was found to be 32% by culture and 45% by PCR. U. urealyticum was recovered from 8 (47%) and 37 (45%) symptomatic men and women, respectively. The agreement between PCR and culture was 93.75%. PCR improved the test sensitivity by 13% compared to culture. The results confirm the need to use a sensitive and reliable molecular method to prevent the underdiagnosis of ureaplasma infection and to facilitate better clinical management of this infection in India.  相似文献   
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In the traditional approach to buffering of H(+) during metabolic acidosis, the sole focus is on lowering the H(+) concentration, but this overlooks several important points. First, increased binding of H(+) to proteins changes their charge, shape, and possibly function. Second, organs in which buffering of H(+) occurs is not assessed even though it would be advantageous to spare brain proteins in this process. Third, only the arterial and not the capillary PCO(2) of individual organs is considered. This article provides a "brain protein-centered" view, which leads to different conclusions concerning the way H(+) are removed physiologically.  相似文献   
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BACKGROUND:

Octogenarians are the fastest growing population in Canada and have also been referred for coronary artery bypass grafting (CABG) with increasing frequency during the past decade.

OBJECTIVE:

To examine the changing trends in preoperative risk profiles, postoperative outcomes and hospital resource use in the octogenarian population.

METHODS:

A retrospective review was conducted to identify all patients 80 years of age or older who underwent isolated CABG at the Toronto General Hospital (Toronto, Ontario) between 1990 and June 2005. To examine the effect of time on preoperative risk, patients were divided into three groups based on year of operation: 1990 to 1994, n=92; 1995 to 1999, n=202; and 2000 to June 2005, n=314.

RESULTS:

The preoperative risk profile of octogenarians undergoing CABG has changed over the years. The percentage of patients with diabetes, dyslipidemia, hypertension and left main disease increased over time (P<0.05). However, the requirement for urgent/emergent operations decreased. In-hospital mortality declined from 7.1% (1990 to 1999) to 3.2% (2000 to June 2005, P=0.02). The prevalence of low cardiac output syndrome, intra-aortic balloon pump insertion and stroke decreased over time. Preoperative myocardial infarction (OR 4, P=0.0004), left main disease (OR 3.7, P=0.0013) and year of operation (1990 to 1994 [OR 3.3, P=0.03]; 1995 to 1999 [OR 2.9, P=0.02]) independently predicted in-hospital mortality. Hospital resource use in terms of hours on ventilator, length of stay in the intensive care unit and postoperative length of stay decreased over time (P<0.0001).

CONCLUSION:

Despite a changing risk profile, hospital outcomes of octogenarians were improved over time with a reduction in hospital resource use. The results suggest that CABG can and should be performed in this expanding population.  相似文献   
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