Prospective investigation of transfusion transmitted infection in recipients of over 20 000 units of blood. TTI Study Group

Adverse Effects of Perioperative Blood Transfusion in Spine Surgery

BACKGROUND

Perioperative blood transfusion is often necessary during spine surgery because of blood loss from the surgical field during and after surgery. However, blood transfusions are associated with a small but significant risk of causing several adverse events including hemolytic transfusion reactions and transfusion-associated circulatory overload. Moreover, many prior publications have noted increased rates of perioperative morbidity and worsened outcomes in spine surgery patients who received blood transfusions. We performed a systematic review of the literature to better characterize the effects of blood transfusion on spine surgery outcomes.

METHODS

The PubMed/MEDLINE database was queried using the composite key word "transfus∗ AND 'spine surgery.'" A title and abstract review were performed to identify articles for final inclusion.

RESULTS

A title and abstract review of the resulting 372 English-language articles yielded 13 relevant publications, which were subsequently incorporated into this systematic review. All included studies were retrospective, nonrandomized analyses.

CONCLUSIONS

Overall, prior literature indicates a relationship between perioperative blood transfusion and worsened outcomes after spine surgery. However, the available data represent level IV evidence at best. In the future, prospective, randomized, controlled studies may help define the effects of perioperative blood transfusion on spine surgery outcomes.

A comparison of the efficacy of autologous fibrin glue/platelet-poor plasma versus suction drainage in preventing hematoma and seroma in rhytidectomy: A randomized, double-blind, controlled study

BACKGROUND

One of the most feared complications of rhytidectomy is the formation of hematoma and seroma, which may harm patients' health and compromise the surgical outcome.

OBJECTIVE

To compare the efficacy of autologous fibrin glue/platelet-poor plasma versus suction drainage in preventing surgical complications such as hematoma and seroma following rhytidectomy procedures.

METHODS

A prospective, randomized, double-blind, controlled study was conducted to compare the efficacy of the two interventions. Seventy-two patients were selected and divided into two groups of 36 (autologous fibrin glue versus suction drainage). Forty-eight hours after the procedures, all patients underwent ultrasound examination, always by the same radiologist, to measure the volume of exudate under the facial skin flaps.

RESULTS

The mean total volume of exudate was 3.21 mL in the suction drainage group and 1.02 mL in the fibrin glue group, with effect size of 68.1% and confidence interval of 55.3 to 77.2 (P < 0.001).

CONCLUSIONS

Results significantly favor the use of fibrin glue and show that it was 68.1% more effective than suction drainage in preventing hematoma or seroma in rhytidectomy procedures.

[Platelet collection in cardiac surgery: first experience with apheresis at the General Hospital in Douala]

Cardiac surgery with extracorporeal circulation (ECC) is usually associated with the loss of a significant amount of blood. Adequate prophylaxis against blood loss and good perioperative hemostasis are known as processes limiting postoperative bleeding. Until now, the need for platelets in patients operated with extracorporeal circulation in our Department has been compensated for by total blood transfusion or platelet concentrates collected from several donors. We here report our first experience with platelet concentrate collection by apheresis at the General Hospital in Douala.

Seroprevalence of transfusion transmitted infections among blood donors in Gash Barka Zonal Blood Transfusion Center, Barentu, Eritrea, 2014 through 2017

Background

Transfusion-transmissible infections pose a major health risk in developing countries, including Eritrea. In the present study, we sought to determine the prevalence of specific transfusion transmitted infections (TTIs) and the associated risk factors among blood donors at a newly established regional blood transfusion center in Barentu, Eritrea.

Methods

The seroprevalence of markers for specific TTIs by sex, age, educational status, residence, occupation, and donor type was evaluated for donors who donated blood between July 2014 and April 2017. The relationship between TTIs and the stated factors was evaluated using the Pearson Chi-square test/Fishers exact test. Adjusted and unadjusted binary logistic regression models were employed to estimate the odds ratio (OR) and 95% confidence interval (CI) for the occurrence of TTIs. A two-sided p-value < 0.05 was considered statistically significant.

Result

A total of 1939 donors were included in this study. Majority of the donors were males (88.2%), urban residents (68.8%), greater than 25 years of age (67%), and family replacement blood donors (FRBD) (59.7%). Two hundred and fifty (12.9%) donors were infected by at least one TTI. The cumulative seroprevalence of Human immunodeficiency virus, Hepatitis B virus, Hepatitis C virus and syphilis were 16 (0.8%), 97 (5%), 13 (0.7%) and 140 (7.2%), respectively. Out of the total 266 infected donors, the prevalence of co-infection was 16 (0.8%). In the adjusted model, the OR and 95% CI for the seropositivity for any TTI associated with age, no formal education, elementary school educational level, and junior school educational level were 1.02 (95% CI: 1.01–1.04), 4.4 (95% CI: 2.58–7.49), 2.67 (95% CI: 1.49–4.80), and 2.00 (95% CI: 1.14–3.52), respectively. In addition, blood from FRBD had an increased likelihood of contamination with at least one TTI, with an OR (95% CI) of 1.56 (1.10–2.21).

Conclusion

The prevalence of transfusion-transmissible infections is relatively high. In particular, specific groups in the population appear to be disproportionally affected. Therefore, targeted sensitization campaigns should be implemented in the future.

Clinical utility of endocrine markers predicting myocardial siderosis in transfusion dependent thalassemia major

BACKGROUND

Endocrinopathy due to iron overload is the most common morbidity whereas myocardial siderosis causing toxic cardiomyopathy is the leading cause of mortality among patients with transfusion dependent thalassemia major (TDTM). If detected early, this can be treated with aggressive chelation. T2* cardiac magnetic resonance imaging (CMR) guided chelation protocols are now the gold standard but have limited availability in low and middle-income countries. We hypothesized that markers of endocrine dysfunction would correlate with T2* CMR and can be used to predict the severity of myocardial siderosis and guide chelation therapy.

METHODOLOGY

We undertook a multicenter retrospective study of 280 patients with TDTM to assess the prevalence of endocrinopathies and the predictive value of a number of individual and composite markers of endocrinopathy with T2* CMR.

RESULTS

The prevalence of hypogonadism, stunting, hypoparathyroidism, and hypothyroidism was 82%, 69%, 40%, and 30%, respectively. The sensitivity of hypogonadism and stunting predicting severe myocardial siderosis was 90% and 80%, respectively.

CONCLUSION

We conclude that clinical markers of endocrine dysfunction, especially hypogonadism (positive likelihood ratio [LR+] = 1.4, 95% confidence interval [CI] = 1.0-1.9; positive predictive value [PPV] = 77%, 95% CI = 70-82; negative predictive value [NPV] = 57%, 95% CI = 34-77] and stunting (LR+ = 1.3, 95% CI = 1.1-1.6; PPV = 64%, 95% CI = 60-69; NPV = 55%, 95% CI = 45-64) in TDTM can predict severe myocardial siderosis and can potentially guide chelation therapy, especially where access to T2* CMR is limited.

Prevalence, incidence and residual risk of transfusion-transmitted hepatitis C virus and human immunodeficiency virus after the implementation of nucleic acid testing in Italy: a 7-year (2009-2015) survey

BACKGROUND

In Italy nucleic acid testing (NAT) became mandatory for hepatitis C virus (HCV) in 2002 and for human immunodeficiency virus (HIV) and hepatitis B virus in 2008. The aim of this study was to monitor the incidence and prevalence of HIV and HCV infections in Italian blood donors and the current residual risk of these infections after the introduction of NAT.

MATERIALS AND METHODS

The Italian national blood surveillance system includes data from tests used to screen for transfusion-transmissible infections. During the period of this survey (2009-2015), the NAT methods used were the transcription-mediated amplification test, for individual donor testing, and polymerase chain reaction analysis, mainly for pools of six donors. Prevalence and incidence were calculated. Three published formulae were applied to estimate the residual risk (the window period ratio model and the formulae recommended by the European Medicines Agency and the World Health Organization).

RESULTS

Overall, 12,258,587 blood donors and 21,808,352 donations were tested for HCV and HIV. The prevalence of HCV decreased from 110.3×10⁵ to 58.9×10⁵ in years 2009 and 2015, respectively, while that of HIV remained stable over time (15.5×10⁵ vs 15.4×10⁵). The incidence of HCV decreased from 3.19×10⁵ in 2009 to 1.58×10⁵ in 2015, while the incidence of HIV did not show any significant fluctuations (average incidence 4.39×10⁵). The residual risk of a viraemic unit entering the blood supply was estimated to be 0.077×10⁶ or 1 in 12,979,949 donations for HCV and 0.521×10⁶ or 1 in 1,917,250 for HIV, according to the window period ratio model, and lower with the other two formulae.

DISCUSSION

HCV infection has declined over time in both first-time and repeat donors, while the data for HIV infection are stable. All three methods employed in this study showed that the residual risk of transmitting HCV or HIV through an infected blood unit is currently very low in Italy, but there are considerable differences in estimates between methods. Thus, harmonisation of these methods is advisable.

Efficacy and Safety of Artiss Fibrin Tissue Sealant Use in Rhytidectomy: A Review of 120 Cases

Hematoma formation has persisted as the most common complication in rhytidectomy. The objective of this study is to determine the efficacy and safety of Artiss (Baxter) for use in rhytidectomies. In addition, we determine the use of fibrin tissue sealants by facial plastic surgeons. In this retrospective chart review, 120 patients in a single private practice were identified who underwent a rhytidectomy from August 2013 to January 2015 by a single facial plastic surgeon. The last 60 rhytidectomies performed with Tisseel (Baxter) were compared with the first 60 rhytidectomies performed with Artiss.

All perioperative or postoperative complications were identified and recorded, focusing on the incidence of hematoma. In addition, a six-question survey was created and sent to all members of the American Academy of Facial Plastic and Reconstructive Surgery. Results of the survey were recorded and analyzed for trends or patterns in the data. In total, 120 patients were assessed. In the Tisseel group, two complications of fluid collection requiring needle aspiration were recorded. No other complications were found. In the Artiss group, 10 complications were recorded, including 9 fluid collections requiring needle aspiration and 1 hematoma. In total, 179 members of the American Academy of Facial Plastic and Reconstructive Surgery completed the six-question survey. Of all respondents, 61 (34%) use tissue sealants for rhytidectomies, whereas 118 (66%) do not. Artiss is efficacious and safe for use in rhytidectomies. Its use obviates the need for surgical drains, and complications are minimal and similar in rate to the use of Tisseel.

PREVALENCE OF OCCULT HEPATITIS B INFECTION IN IRANIAN CANCER PATIENTS BEFORE CHEMOTHERAPY TREATMENT

BACKGROUND

Occult hepatitis B infection is characterized by negative hepatitis B surface antigen (HBsAg) and also detectable hepatitis B virus (HBV) -DNA, with or without hepatitis B core antibody (anti-HBc). HBV reactivation in individuals under immunosuppressive therapy is critical, occurring in occult HBV.

OBJECTIVE

In this study, we aimed to determine the prevalence of occult HBV infection among hepatitis B surface antigen negative in cancer patients before receiving chemotherapy.

METHODS

Sera from 204 cancer patients who were negative for HBsAg, were tested for anti-HBc antibodies. The samples that were negative for HBsAg but positive for anti-HBc also examined for HBV-DNA by polymerase chain reaction (PCR).

RESULTS

Of the 204 HBsAg negative blood samples, 11 (5.4%) samples were positive for anti-HBc antibodies. HBV-DNA was detected in 9/11 (81%) of anti-HBc positive samples. Occult HBV infection in hematological cancers was more than solid cancers, 4.8% and 4.3% respectively. There was no significant difference in HBc antibody positivity based on vaccination, previous blood transfusions, history of familial hepatitis or biochemical parameters (ALT, AST, total and direct bilirubin levels) (P>0.05).

CONCLUSION

Screening of occult HBV infection by HBsAg, HBV DNA and anti HB core antibody should be suggested as a routine investigation in cancer patients before receiving chemotherapy.

Fibrin tissue adhesive for face- and necklift

INTRODUCTION

Although available for decades, fibrin-based tissue adhesives (FTAs) have enjoyed only variable popularity in aesthetic surgery since their introduction in the 1980s. Whilst benefits in facelift surgery have been reported for a range of measures, including expanding haematoma, oedema and ecchymosis, irrefutable evidence has not yet been forthcoming. We instigated a prospective study to test the hypothesis that an underappreciated property of FTA, namely its ability to distribute tension, would reduce complications and revision due to early relapse.

PATIENTS AND METHODS

The study group comprised 100 consecutive facelifts with FTA. The comparative group comprised the immediate preceding 100 patients who underwent similar interventions, but with drains instead of FTA. All surgery was undertaken by the senior author using standard techniques and statistical analysis employing Fisher's exact test.

RESULTS

The groups were comparable in age, gender distribution, co-morbidity and declared cigarette smoking. Complications were recorded in 24 patients with significantly more in the comparative group (p = 0.048), particularly hypertrophic scarring (p = 0.029). Although there appeared a greater prevalence of revision and cutaneous necrosis in the comparative group, these did not reach statistical significance.

DISCUSSION

To the many published benefits, we can add that FTA can reduce complications, particularly hypertrophic scarring, and it now forms an important part of our facelift practice.

[Occult hepatitis B virus infection: transmission and reactivation]

Occult HBV infection (OBI) is defined as presence of HBV DNA in the liver tissue in patients with serologically undetectable HBsAg. There are differences in virologic and serological profiles of OBI. Majority of OBI are positive for anti-HBs and/or anti-HBc and minor portion are negative for all HBV markers. However, there are no HBV mutations in the surface and its regulatory regions. HBV infection persists by the presence of covalently closed circular DNA (cccDNA) within the infected hepatocytes, which serves as a reservoir for future infection. OBI increases the risk of HBV transmission through transfusion, hemodialysis, and organ transplantation. Therefore effective measures should be employed to screen OBI. Antiviral therapy is needed in HBsAg-negative transplant patients who are anti-HBc positive to prevent the recurrence of HBV infection. Since HBV replication is strongly suppressed by immune surveillance system in OBI patients, immunosuppression results in massive HBV replication. This leads to acute hepatitis and sometimes mortality when immune surveillance is recovered after stopping immunosuppressive drugs/anticancer chemotherapy. Therefore, narrow surveillance is required to recognize the viral reactivation and start antiviral agents during immunosuppressive therapy/anticancer chemotherapy in patients with OBI.

Occult hepatitis B: clinical viewpoint and management

Occult HBV infection (OBI) is defined as HBV DNA detection in serum or in the liver by sensitive diagnostic tests in HBsAg-negative patients with or without serologic markers of previous viral exposure. OBI seems to be higher among subjects at high risk for HBV infection and with liver disease. OBI can be both a source of virus contamination in blood and organ donations and the reservoir for full blown hepatitis after reactivation. HBV reactivation depends on viral and host factors but these associations have not been analyzed thoroughly. In OBI, it would be best to prevent HBV reactivation which inhibits the development of hepatitis and subsequent mortality. In diverse cases with insufficient data to recommend routine prophylaxis, early identification of virologic reactivation is essential to start antiviral therapy. For retrieving articles regarding OBI, various databases, including OVID, PubMed, Scopus, and ScienceDirect, were used.

Anemia and blood transfusions in critically ill patients

Anemia is common in critically ill patients. As a consequence packed red blood cell (PRBC) transfusions are frequent in the critically ill. Over the past two decades a growing body of literature has emerged, linking PRBC transfusion to infections, immunosuppression, organ dysfunction, and a higher mortality rate. However, despite growing evidence that risk of PRBC transfusion outweighs its benefit, significant numbers of critically ill patients still receive PRBC transfusion during their intensive care unit (ICU) stay. In this paper, we summarize the current literature concerning the impact of anemia on outcomes in critically ill patients and the potential complications of PRBC transfusions.

Management of occult hepatitis B virus infection: An update for the clinician

Occult hepatitis B virus (HBV) infection (OBI) is defined by the presence of HBV DNA in the liver tissue of individuals who test negative for hepatitis B surface antigen (HBsAg). Patients who have recovered from acute hepatitis B can carry HBV genomes for a long time and show histological patterns of mild necro-inflammation, even fibrosis, years after the resolution of acute hepatitis, without showing any clinical or biochemical evidence of liver disease. At least in conditions of immunocompetence, OBI is inoffensive itself, but when other relevant causes of liver damage are present it might make the course of the liver disease worse. The risk of HBV transmission through transfusion is related to blood donations negative for HBsAg that have been collected during the pre-seroconversion period or during chronic OBI. Use of HBV nucleic acid amplification testing and multivalent anti-HBs antibodies in the HBsAg assays is recommended for detection of true and false OBI, respectively. It is not known if prior hepatitis B immunization with an optimal anti-HBs response in cases of HBV transmission through organ transplantation can effectively modulate or abort the infection. Use of antiviral agents as prophylaxis in patients with serological evidence of past HBV infection prevents reactivation of OBI after transplantation in most cases. Reactivation of OBI has been observed in other conditions that cause immunosuppression, in which antiviral therapy could be delayed until the HBV DNA or HBsAg becomes detectable. OBI might contribute to the progression of liver fibrosis and hepatocellular carcinoma development in patients with chronic liver disease.

Bayesian evaluation of the human immunodeficiency virus antibody screening strategy of duplicate enzyme-linked immunosorbent assay in Xuzhou Blood Center, China

BACKGROUND

Accurate estimation of the risk of human immunodeficiency virus (HIV) infection through transfusion is essential for monitoring blood safety. The risk, however, is so low that it can only be estimated by mathematical modeling. With the Bayesian dependence model, this study evaluates the HIV antibody screening strategy of duplicate enzyme-linked immunosorbent assay (ELISA) in Xuzhou Blood Center and therefore estimates part of the total risks of transfusion-transmitted HIV infection.

STUDY DESIGN AND METHODS

Data from Xuzhou Blood Center between 2004 and 2008 were used. Information was obtained on donor profiles and screening and confirmatory test results. The portion of the risks of HIV infection through transfusion concerned was estimated by evaluating the screening algorithm in terms of its accuracy and predictive power with the Bayesian dependence model.

RESULTS

A total of 234,602 donations from voluntary blood donors in Xuzhou Blood Center were screened for HIV antibody. For the study screening algorithm, its sensitivity, specificity, false-positive predictive value (FPPV), and false-negative predictive value (FNPV) were 0.9951 (95% Bayesian credible interval [BCI], 0.9763-0.9997), 0.9991 (95% BCI, 0.9990-0.9992), 0.9647 (95% BCI, 0.9018-0.9923), and 1.52 × 10(-7) (95% BCI, 7.31 × 10(-9) -1.15 × 10(-6) ), respectively. For the positive detection rate (9.60 × 10(-4) ) and FPPV (0.9647), the differences between their own Bayesian median estimates and real values were 2.70 × 10(-5) and -0.0033, respectively.

CONCLUSIONS

The HIV antibody screening algorithm of duplicate ELISA is well evaluated in its accuracy and predictive power with the Bayesian dependence model. The FNPV measures the part of the risks of transfusion-associated HIV transmission concerned.

Lookback study of HTLV-1 and 2 seropositive donors and their recipients in Belo Horizonte, Brazil

The objective of this study was to perform lookback study in recipients of blood components from human T-lymphotropic virus (HTLV) seropositive donors. HTLV-1/2 may be transmitted by blood transfusion. Brazil is an endemic area for the virus and its screening in blood donors is mandatory since 1993. Hemominas Foundation (HF) is the public transfusion centre in Minas Gerais, Brazil. Data on HTLV-1/2 seropositive donors and recipients from 1993 to 2004 were obtained at HF and 24 contracting hospitals. From 1993 to 2004, HTLV-1/2 enzyme immunoassay (EIA) was performed in 918 678 donations of approximately 422 600 blood donor candidates. Of these, 456 donors (0.1%) were reactive and confirmed by Western blot (WB): 449 HTLV-1 and 7 HTLV-2. Sixty-six (14.5%) were repeat donors and had 194 blood cellular components produced from their previous donations. Of the distributed components, 119/146 (81.5%) had the recipient traced, with a total of 114 individuals. Of these, only 13 recipients were tested: six (46%) were HTLV-1 positive (four recipients of red cell units, two of platelets) and seven (54%) were negative (six of red cell units and one of platelets). Eleven did not respond and 62/114 (54.0%) were deceased. Another 28/114 (25.0%) could not be located. All six seropositive HTLV-1 recipients identified had no symptoms suggestive of HTLV-1-associated diseases. Acellular components, when used alone, were not associated with HTLV seropositivity. HTLV-1 transmission by cellular blood components occurred before screening for the virus was introduced. Haemovigilance was difficult to perform due to unavailability of computer systems before 1999 and to inadequate medical records at hospitals.

Adult T-Cell Leukemia/Lymphoma (ATLL): Report of Two Fully Documented Hellenic Patients

ATLL is etiologically associated with HTLV-I retrovirus. A population of 10 to 20 million worldwide is estimated to be infected by the virus, but only 1-4% develop ATLL during a 70-year lifespan. The latency period is more than 30 years. The aim of this study was to report two cases of ATLL in Greek patients with the concomitant study of their family members. A 55-year-old woman and a 59-year-old man presented with leucocytosis and lymphocytosis. Both were asymptomatic and physical examination was unremarkable except for minimal lymphadenopathy in the second patient. In both patients blood smears showed small-to-medium-sized, multilobulated lymphocytes, with different degrees of nuclear irregularity. Immunophenotypic study was as follows: CD2 + (97%), CD3 + (95%), CD5 + (95%), CD3/CD4 + (93%), CD3/CD25 + (84%), CD7 -/CD4 + (89%) CD2 + /HLA-DR + (53%), TCRabeta + (96%) and CD7-(7%). Bone marrow biopsy revealed a normal cellularity with dyserythropoiesis and scattered small lymphocytes (CD4 + on immunostaining) Serum HTLV I and II antibodies were positive. T-cell receptor gamma-chain rearrangement was positive in blood lymphocytes by PCR. Cytogenetic analysis showed complex karyotypic abnormalities. DNA analysis by PCR demonstrated the integration of the HTLV-I DNA in the DNA of the neoplastic T cells. Both patients rapidly developed acute type ATLL. In the first patient multiple subcutaneous nodules on the palmar surface of both hands were also observed. She received deoxycoformycin, which was stopped because of autoimmune hemolytic anemia. Corticosteroid treatment was initiated, with gradual improvement. She suffered from recurrent opportunistic infections. She is currently under interferon and zidovudine therapy with stable blood parameters. Chemotherapy was administered to the other patient with > 50% initial response. Both patients' families were tested for serum anti HTLV-I antibodies and their mates were found to be positive; they also had detectable viral DNA by PCR analysis while asymptomatic, with no abnormal clinical findings and normal white blood cell count and morphology. In conclusion, the two aforementioned patients are the first fully documented ATLL patients described in Greece. Investigation for HTLV-I antibodies should be mandatory in all patients with T-cell lymphoproliferative disorders.

Impact of nucleic acid testing for hepatitis B virus, hepatitis C virus, and human immunodeficiency virus on the safety of blood supply in Italy: a 6-year survey

BACKGROUND

Nucleic acid testing (NAT) for hepatitis C virus (HCV) and human immunodeficiency virus (HIV) has been implemented in several European countries and in the United States, while hepatitis B virus (HBV) NAT is still being questioned by opinions both in favor and against such an option, depending on the HBV endemicity, health care resources, and expected benefits.

STUDY DESIGN AND METHODS

This survey was aimed to assess the NAT impact in improving the safety of blood supply in Italy, 6 years after implementation. The study involved 93 Italian transfusion centers and was carried out in 2001 through 2006. A total of 10,776,288 units were tested for the presence of HCV RNA, 7,932,430 for HIV RNA, and 3,405,497 for HBV DNA, respectively.

RESULTS

Twenty-seven donations or 2.5 per million tested were HCV RNA-positive/anti-HCV-negative; 14 or 1.8 per million units tested were HIV RNA-positive/anti-HIV-negative; and 197 or 57.8 per million donations tested were HBV DNA-positive/hepatitis B surface antigen-negative. Of the latter, 8 (2.3/10(6)) were collected from donors in the window phase of infection and 189 (55.5/10(6)) from donors with occult HBV. Sixty-eight percent of the latter donors had hepatitis B surface antibody, 74.5 percent of whom with concentrations considered protective (>or=10 mIU/mL).

CONCLUSION

NAT implementation has improved blood safety by reducing the risk of entering 2.5 HCV and 1.8 HIV infectious units per million donations into the blood supply. The yield of NAT in detecting infectious blood before transfusion was higher for HBV than for HCV or HIV. However, the benefit of HBV NAT in terms of avoided HBV-related morbidity and mortality in blood recipients needs to be further evaluated.

Occult hepatitis B virus in liver tissue of individuals without hepatic disease

BACKGROUND/AIMS

While many data are available concerning occult hepatitis B virus (HBV) infection in patients with hepatic disorders, there is little information about this cryptic infection in individuals without liver disease. The aim of this study was to investigate the prevalence of occult HBV in the general population by examining liver specimens from a large series of HBV-surface-antigen negative individuals with no clinical and biochemical evidence of liver disease.

METHODS

The presence of HBV DNA was evaluated by testing, through polymerase chain reaction techniques, DNA extracts from 98 liver-disease-free individuals who underwent liver resection or needle biopsy during abdominal surgery. Sixteen of them were anti-HBV-core antigen (anti-HBc) positive and 82 were HBV serum-marker negative. All patients were negative for antibody to hepatitis C virus.

RESULTS

Occult HBV infection was revealed in 16 of the 98 cases (16.3%). In particular, 10/16 anti-HBc positive (62.5%) versus 6/82 (7.3%) HBV-seronegative individuals were occult carriers (p<0.0001).

CONCLUSIONS

This study revealed that about 1/6 of the Italian general population might be carriers of occult HBV infection, and this condition is significantly associated with the anti-HBc positive status.

Survey of Hepatitis Markers Among Donors in the State of Qatar

A total of 78,428 blood units collected by the Blood Donor Unit, Hamad Medical Corporation, Doha, from the multinational donors of Qatar (28,622 Qatari nationals donors and 49,806 Non-Qatari donors) in the period January 1994 to Dececember 2001 were screened for hepatitis markers. About 10,382 units (13.2%) were discarded because of positivity for one or more hepatitis markers; 769 units (0.9%) were positive for hepatitis-B surface antigen (HBsAg), 8516 units (10.9%) were positive for hepatitis-B core antibodies (HBcAb) and 1097 units (1.39%) were positive for hepatitis C (HCV) antibodies. There was no significant difference between the rate of positivity for HBcAb and HBsAg in indigenous Qataris and Non-Qataris despite a slightly higher rate ofpositivity for HCV antibodies in the Non-Qatari group. An outstanding finding was the significantly high rate of positivity for HCV antibodies in Egyptian donations (11.2%), which accounted for 31.2% of all discards for the Non-Qatari group. As the Blood Donor Unit at HMC is the only blood collection center in Qatar it is assumed that the results could be representative of the country as a whole.

Experience with Fibrin Glue in Rhytidectomy

BACKGROUND

The authors conducted a large, prospective, controlled trial of fibrin glue in rhytidectomy using a wide set of variables.

METHODS

Two hundred consecutive patients undergoing elective rhytidectomy were studied. One hundred patients received fibrin glue over a 1-year period and were followed prospectively. Another 100 patients from the previous year who had not received fibrin glue had their charts reviewed retrospectively. All patients underwent bilateral face lifts using the deep plane technique.

RESULTS

The following data were observed for the glue versus nonglue patients: expanding hematoma rate, 1 percent versus 3 percent (p > 0.05); seroma rate, 1 percent versus 7 percent (p > 0.05); and prolonged induration, edema, and ecchymosis, 0 percent versus 22 percent (p < 0.05). The pain score for glue versus nonglue patients was 100 percent minimal versus 95 percent minimal and 5 percent moderate (p > 0.05). The average score for patient satisfaction (scale, 1 to 10, with 10 being best) for glue versus nonglue patients was 9.5 versus 9.0 (p > 0.05).

CONCLUSIONS

The use of fibrin glue was associated with some benefits for rhytidectomy. Fibrin glue eliminated the use of drains. The difference in expanding hematoma was clinically, but not statistically, significant. The seroma rate was decreased and neared statistical significance. There was an impressive immediate decrease in postoperative swelling. The fibrin glue was most advantageous in eliminating prolonged induration, edema, and ecchymosis. There were no statistical differences between groups for patient satisfaction or pain. The use of fibrin glue has been shown to reduce some of the morbidity and severe complications of face lifting.

Pre-operative predeposit autologous donation in children presenting for elective surgery: a review

Predeposit Autologous blood donation (PAD) in children decreases the life-time complications associated with allogeneic blood. These complications include transmission of known or unknown pathogens and alloimmunization against future blood transfusions, organ transplants and pregnancies. In view of the potential long term benefits of PAD should it be considered a component of paediatric blood conservation programs. This paper reviews the literature to explore the risk of benefit analysis of adopting PAD in paediatric practice.

Occult hepatitis B virus infection

The persistence of hepatitis B virus (HBV) genomes in HBV surface antigen (HBsAg) negative individuals is termed occult HBV infection. Occult HBV status is associated in some cases with mutant viruses undetectable by HBsAg assays, but more frequently it is due to a strong suppression of viral replication and gene expression. Occult HBV infection is an entity with world-wide diffusion, although the available data of prevalence in various categories of individuals are often contrasting because of the different sensitivity and specificity of the methods used for its detection in many studies. Occult HBV may impact in several different clinical contexts, including the transmission of the infection by blood transfusion or organ transplantation and its acute reactivation when an immunosuppressive status occurs. Moreover, much evidence suggests that it can favour the progression of liver fibrosis and above all the development of hepatocellular carcinoma.

Residual risk of transfusion-transmitted human immunodeficiency virus, hepatitis C virus, and hepatitis B virus infections in Italy

BACKGROUND

Estimating the risk of transfusion-transmitted infections (TTIs) is essential for monitoring blood safety. The residual risk of TTI was estimated for nearly 90 percent of the blood supply in Italy.

STUDY DESIGN AND METHODS

Data were analyzed from 1,079,281 repeat donors, corresponding to 5,361,000 donations made in blood transfusion centers throughout Italy in the period 1999 through 2001. The residual risk of transfusion-transmitted human immunodeficiency virus (HIV), hepatitis C virus (HCV), and hepatitis B virus (HBV) infections was estimated with the incidence rate-window period model. The denominator for the incidence rate (i.e., the number of person-years at risk) was estimated on a sample of 5850 donors.

RESULTS

The risk of an infectious donation entering the blood supply, per 1 million donations, was 1.91 (probable range, 0.52-3.32) for HIV, 16.74 (9.57-24.01) for HCV, and 69.16 (43.12-102.70) for total HBV (adjusted for vaccination and hepatitis B surface antigen transience).

CONCLUSION

In Italy, the estimated residual risk of TTI is apparently low, particularly for HIV infection. Although the estimated risks are higher for HCV and HBV, the introduction of mandatory viral detection tests for HCV in 2002 should account for an 80 percent reduction in the HCV risk. Moreover, the ongoing HBV vaccination program will contribute to reducing the risk of transfusion-transmitted HBV.

Occult hepatitis B virus infection: implications in transfusion

Hepatitis B virus (HBV) presents a higher residual risk of transmission by transfusion than hepatitis C virus (HCV) or human immunodeficiency virus (HIV). While most infectious blood units are removed by screening for hepatitis B surface antigen (HBsAg), there is clear evidence that transmission by HBsAg-negative components occurs, in part, during the serologically negative window period, but more so during the late stages of infection. Donations negative for HBsAg, but positive for HBV DNA, with or without the presence of HBV antibodies, correspond to 'occult' HBV infection (OBI). The frequency of OBI depends on the relative sensitivity of both HBsAg and HBV DNA assays. It also depends on the prevalence of HBV infection in the population. OBI may follow recovery from infection, displaying antibody to hepatitis B surface antigen (anti-HBs) and persistent low-level viraemia, escape mutants undetected by the HBsAg assays, or healthy carriage with antibodies to hepatitis B e antigen (anti-HBe) and to hepatitis B core antigen (anti-HBc). Over time, in the latter situation, anti-HBe and, later, anti-HBc may become undetectable. The critical question is whether or not OBI is infectious by transfusion. All forms have been shown to be infectious in immunocompromised individuals, such as organ- or bone marrow-transplant recipients. In immunocompetent recipients, there is no evidence that anti-HBs-containing components (even at low titre) are infectious. Anti-HBc only, with HBV DNA, can be associated with infectivity, as can rare cases of HBV DNA without any serological HBV marker. If HBV nucleic acid amplification technology (NAT) is considered, the OBI viral load would usually be < 500 IU/ml, making testing of plasma pools unsuitable unless the sensitivity of NAT significantly increases by genome enrichment or test improvement.

[Efficiency of hepatitis C virus screening before and after blood transfusion]

Efficiency of a viral hepatitis C screening strategy before and after blood transfusion has to be evaluated.

METHODS

Four screening strategies were virtually applied to the population of transfused patients at Rouen University Hospital during 1996 and then compared : the first without any systematic HCV screening test; the second with systematic testing both before and 3 months after transfusion; the third with systematic testing both before and 6 months after transfusion ; the last defined as systematic testing before transfusion only. The efficacy (i.e. number of positive tests), the efficiency (i.e. average cost per positive test) and the marginal costs of moving from a strategy to another one were assessed using decision analysis.

RESULTS

The efficacy of systematic screening test before transfusion only (361 per positive test), systematic testing both before and three months after (523 per positive test) or six months after (488 per positive test) transfusion was similar, but the efficacy of the strategy without any systematic screening test (385 per positive test) was lower. The systematization of screening test both before, and three months, or 6 months after transfusion lead to a marginal cost of 619 , and 559 per positive test respectively. The systematization of testing before transfusion only lead to a marginal cost of 343 per positive test. Adding systematic testing after transfusion lead to a marginal cost of 5824 per positive test.

CONCLUSION

Systematic screening tests before transfusion only can be considered as the most efficient strategy.

Trends in Major Transfusion-transmissible Infections among Blood Donors over 17 Years in Istanbul, Turkey

Infection with hepatitis B virus (HBV), hepatitis C virus (HCV), human immunodeficiency virus (HIV) and syphilis are serious complications of blood transfusion. These infections are routinely screened by blood banks; such tests are obligatory for transfusion safety in Turkey. The results of screening 1 737 943 blood donations from blood centres in Istanbul between 1 January 1987 and 31 December 2003 for HBV, HCV, HIV and syphilis were analysed retrospectively. Hepatitis B surface antigen rates fell from 5.98% in 1987 to 2.07% in 2003. Anti-HCV seropositivity was found to be approximately 0.5%, whereas anti-HIV seropositivity was approximately 0.001%. Rapid plasma reagin rates (test for syphilis) were 0.04% in 1987, and increased to 0.2% in 2002. The decreasing trends observed in data from the 17-year period studied indicate the value of safety measures taken, in particular the implementation of donor screening procedures in 1997.

Screening, Diagnosis and Advances in Aortic Aneurysm Surgery

BACKGROUND

Aortic aneurysms are common in the elderly and a frequent cause of sudden death. As elective aneurysm repair has a mortality drastically lower than that associated with rupture, the emphasis must be on early detection and repair free from complications. Recent advances include ultrasound screening for asymptomatic abdominal aortic aneurysm (AAA) and clinical trials on the size of AAA that require repair. Pre-operative assessment, management of cardiac risk, autologous blood transfusion strategies, and endovascular stent graft technology to avoid major open surgery are all issues to be addressed.

METHODS

Following a computerized Medline search for publications on the detection and treatment of abdominal and thoracic aortic aneurysm, the publications identified were then read and the references within those publications examined for further publications on this topic. We have reviewed these publications without attempting a meta-analysis.

RESULTS

Randomized population studies have addressed ultrasound screening for AAA. Attendance for screening was good and AAA detection inexpensive. Screening men from 65 years reduces the mortality from rupture and is cost-effective. Open thoracic and abdominal aneurysm repair has a mortality of around 8%, with myocardial infarction being a frequent cause of death. Pre-operative reduction of cardiac risk by cardiac investigations and beta-blockade may reduce this mortality. Autologous transfusion techniques such as acute normovolaemic haemodilution and interoperative cell salvage reduce the need for allogeneic blood and the complications associated with open surgery. Minimally invasive endovascular repair is now possible for 40% of the AAA and an increasing proportion of thoracic aneurysms.

CONCLUSIONS

The combination of screening, reduced pre-operative risk, and new minimally invasive techniques extends aortic aneurysm treatment into an increasingly elderly population. The combination of these techniques will reduce mortality from ruptured aortic aneurysm in the elderly and also reduce the stress associated with aneurysm surgery.

Reconstructing and predicting the hepatitis C virus epidemic in Greece: increasing trends of cirrhosis and hepatocellular carcinoma despite the decline in incidence of HCV infection

In this study, a comprehensive methodology for modelling the hepatitis C virus (HCV) epidemic is proposed to predict the future disease burden and assess whether the recent decline in the incidence of HCV may affect the future occurrence of cirrhosis and hepatocellular carcinoma (HCC) cases. Using the prevalence of HCV, the distribution of chronic hepatitis C (CHC) patients within the various transmission groups and their infection-onset times, it was possible to reconstruct the incident infections per year in the past that progressed to CHC in Greece. The natural history of the disease was simulated in subcohorts of newly infected subjects using transition probabilities derived either empirically between fibrosis stages 0-4 or from literature review. Annual estimates of the incidence and prevalence of CHC by fibrosis stage, HCC and mortality in Greece were obtained up to 2030. HCV incidence peaked in the late 1980s at five new infections/10,000 person-years. Under the assumption of 20-100% decline in HCV incidence after 1990, the cumulative number of incident cirrhosis and HCC cases from 2002-2030 was projected to be lower by 9.6-48.2% and 5.9-29.5%, respectively, than that estimated under the assumption of no decline. However, the prevalent cirrhotic/HCC cases and HCV-related deaths are predicted to decline in the next 30 years only under the assumption of complete elimination of new HCV infections after 1990. Despite the progress in the reduction of HCV transmission, primary prevention does not seem adequate to reverse the rise in the incidence of cirrhosis and HCC.

Cell salvage does not minimize perioperative allogeneic blood transfusion in abdominal vascular surgery: a systematic review

PURPOSE

To determine whether the use of cell salvage reduces the proportion of patients receiving at least one unit of allogeneic packed red blood cells during the perioperative period of an elective vascular surgery.

SOURCE

We identified all relevant articles through the combined use of electronic searches of the MEDLINE and EMBASE databases, the Cochrane library as well as hand searching of all randomized clinical trials and review articles. The electronic search included articles published between 1966 and April 2001. The search included textword searches using "autotransfusion," "cell salvage," "device," or Medical Subject Headings "autologous blood transfusion" or a "randomized controlled trials" filter.

PRINCIPAL FINDINGS

Five randomized controlled trials (RCT) were identified involving cell salvage and vascular surgeries. In infra renal abdominal aortic aneurysm surgery the risk ratio (the risk of receiving at least one unit of allogeneic red cells) was 0.37 [95% confidence intervals (CI) of 0.06 to 2.36]. In elective aorto-femoral bypass surgery the risk ratio was 0.97 (95% CI of 0.66 to 1.42). The pooled risk ratio for cell salvage in vascular surgery was 0.67 (95% CI of 0.35 to 1.28).

CONCLUSION

Cell salvage, a commonly used technique to recover red cells from the operative field, has been the subject of several studies in vascular surgery. There is insufficient evidence to recommend the routine use of cell salvage in elective abdominal aortic aneurysm and aorto-femoral bypass surgeries. A large RCT would elucidate whether cell salvage is effective as a blood conservation technique.

The role of hospital transfusion committees in blood product conservation

Transfusion committees have been created in different countries to oversee all aspects of blood product transfusion within individual institutions. A fundamental role of hospital transfusion committees is to ensure appropriate blood product use by developing local policies, educating clinicians, and auditing blood use. Unfortunately, this task is hampered by the lack of universally accepted criteria for blood product transfusion. Several examples of specific interventions directed toward improving blood use have been described in the literature. Despite some limitations of these reports, largely because of shortfalls in study design, such interventions appear to be generally effective, but there is not enough evidence to recommend a specific course of action to ensure appropriate blood use. Notwithstanding such problems, a functional hospital transfusion committee can have a major impact on local rates of inappropriate transfusion.

Recombinant erythropoietin in clinical practice

The introduction of recombinant human erythropoietin (RHuEPO) has revolutionised the treatment of patients with anaemia of chronic renal disease. Clinical studies have demonstrated that RHuEPO is also useful in various non-uraemic conditions including haematological and oncological disorders, prematurity, HIV infection, and perioperative therapies. Besides highlighting both the historical and functional aspects of RHuEPO, this review discusses the applications of RHuEPO in clinical practice and the potential problems of RHuEPO treatment.

Estimation of the risk of hepatitis B virus, hepatitis C virus and human immunodeficiency virus infectious donations entering the blood supply in England, 1993-2001

BACKGROUND AND OBJECTIVES

The frequency of hepatitis B virus (HBV), hepatitis C virus (HCV) or human immunodeficiency virus (HIV) infectious donations entering the blood supply in England is too low to monitor using observational studies. The expected frequency of infectious donations can be estimated and these estimates may be used to contribute to monitoring of blood safety and used in the design of strategies to decrease the risk of transfusion-transmitted infections.

MATERIALS AND METHODS

The prevalence and incidence of hepatitis B surface antigen (HBsAg), and antibodies to HCV and HIV (anti-HCV and anti-HIV, respectively) in donors in England, between 1993 and 2001, were used together with data about the length of negative 'window-periods' of current assays for each of these markers and data about test performance, to estimate the number of infectious donations that enter the blood supply. The risks were calculated separately for donations from new donors and from repeat donors, and for the three time periods 1993-95, 1996-98 and 1999-01.

RESULTS

The estimated frequency of infectious donations entering the blood supply in England, between 1993 and 2001 was 1 in 260,000 for HBV and 1 in 8 million for HIV. For HCV, the frequency of infectious donations was 1 in 520,000 during 1993-98 and fell to 1 in 30 million during 1999-2001 when all donations were tested for HCV RNA. The frequency of HBV- and HCV-infectious donations entering the blood supply fell over these 9 years: the frequency of HIV-infectious donations remained essentially unchanged. The risk from donations from new donors was found to be approximately sevenfold higher than the risk from donations from repeat donors.

CONCLUSIONS

The risks of HBV-, HCV- or HIV-infectious donations entering the blood supply in England are very low, and have decreased since 1993. Although the accuracy of these estimates is imperfect, mainly owing to uncertainty in some assumptions and to small numbers of infections, they provide some quantification of the risk of HBV, HCV or HIV transmission by transfusion, and allow comparison of the magnitude of these risks for each infection and over time. The methods we have used have been developed and improved from previously published methods.

High frequency of hepatitis B virus infection in patients with beta-thalassemia receiving multiple transfusions

BACKGROUND AND OBJECTIVES

Hepatitis B virus (HBV) may occasionally be transmitted through transfusion of blood units that are hepatitis B surface antigen (HBsAg) negative but HBV DNA positive. Children with beta-thalassemia are particularly susceptible to HBV because they receive multiple blood transfusions. These children have high infection rates despite vaccination against HBV. Post-vaccination infections may be a result of viruses harbouring surface (S)-gene mutations (e.g. G587A) in a region critical for reactivity to antibody to hepatitis B surface antigen (anti-HBs). The true prevalence of HBV in individuals with beta-thalassemia has not been studied previously.

PATIENTS AND METHODS

Seventy patients with beta-thalassemia (median age 6 years; range 8 months to 22 years; 49 male), who had received seven to 623 (median 61) units of blood each and three doses (10/20 micro g) of HBV vaccine (Engerix B) before presentation to us, were included in the study; 50 of the 70 patients had received transfusions prior to vaccination. Enzyme-linked immunoassay for serological markers [HBsAg, antibody to hepatitis B core antigen (anti-HBc) and quantitative anti-HBs] and polymerase chain reaction (PCR) followed by Southern hybridization for molecular detection of hepatitis B, was performed on all samples. The PCR-amplified product was cloned, sequenced and the nucleotide and deduced amino acid sequences for the HBV S and polymerase (P) genes were analysed for mutations.

RESULTS

Four of 70 (5.7%) individuals with beta-thalassemia were HBsAg positive and 14 (20%) were anti-HBc positive. The prevalence of serological markers increased with number of transfusions (P < 0.01). Of 70 patients, 53 (75.7%) had an anti-HBs titre of > 10 IU/l following vaccination and 17 (24.3%) were non-responders (< 10 IU/l); 22 (31.4%) of the 70 were DNA positive. The frequency of HBV infection in beta-thalassemia was similar in vaccine responders and non-responders. The virus was of subtype ayw (genotype D) in the five DNA-positive samples in which a 388-nucleotide region of the S gene was sequenced. Mutations occurred at 13 positions in the S gene and at 10 positions in the P gene. Hydrophobicity plots revealed differences in amino acid regions 117-165 and 195-211. Some of these amino acid substitutions coincided with the putative cytotoxic T-lymphocyte epitopes of both S and P proteins.

CONCLUSIONS

A high frequency of HBV infection was seen using molecular methods in thalassemic patients. The frequency of infection was similar in vaccine responders and non-responders. A number of mutations were observed in the S gene, which could have implications for viral replication as well as virus-host cell interaction.

The risks associated with blood and blood product transfusion

Although transfusion of blood and blood products is often of life-saving benefit for the many patients who receive transfusions every year, it is not without considerable risk. Nurses need to be aware of these risks so that they can respond to patient anxiety about transfusion. This article outlines risks associated with transfusion and the measures taken to minimize them. Attention will be focused principally on the two most significant risks: transmission of serious blood-borne infection and the potentially fatal acute immune haemolytic reaction that can occur if patients receive incompatible red cells. Other significant adverse effects will be discussed briefly. Recent initiative aimed at monitoring the incidence of these adverse effects and increasing the safety of blood transfusion will be discussed, with special emphasis on the nurse's role in the transfusion process.

Cost-effectiveness of testing for human immunodeficiency virus and hepatitis C virus among blood transfusion recipients

OBJECTIVE

To choose the most cost-effective option for detecting human immunodeficiency virus (HIV-1) and hepatitis C virus (HCV) among blood transfusion recipients.

DESIGN

Cost-effectiveness analysis. Effectiveness was expressed as the number of HIV-1 or HCV infections detected, regardless of whether they were related to transfusion. To estimate costs, we assumed hospital insurance would cover costs related to detection and compensation, when granted.

SETTING

A 2,890-bed acute care teaching hospital in Bordeaux, France.

METHODS

Eight options were defined, from the simplest, which would be to do nothing, to a maximal approach, which would be to keep a serum sample in a serum library for a lookback and perform tests for antibody to HIV-1 and to HCV before and 3 months after transfusion. Data on probabilities and costs were taken from the literature and experiences of French hospitals.

RESULTS

The most cost-effective option was to perform viral antibody testing before transfusions (option 3), which would detect 27 infections per 1,000 patients, for an expenditure of US $1,260 per detected patient Option 6, obtaining a serum sample before transfusion and performing tests for antibody to HIV-1 and to HCV 3 months after transfusion, had a similar cost-effectiveness ratio but detected only 16 infections per 1,000 patients. Performing tests before and 3 months after transfusion (option 4), compared with option 3, would detect 1 additional infection for an additional cost of US $8,322.

CONCLUSION

The most cost-effective options are not specific to blood transfusion recipients and might be more suited to all hospitalized patients.

Cost-Effectiveness of Testing for Human Immunodeficiency Virus And Hepatitis C Virus Among Blood Transfusion Recipients

Objective:

To choose the most cost-effective option for detecting human immunodeficiency virus (HIV-1) and hepatitis C virus (HCV) among blood transfusion recipients.

Design:

Cost-effectiveness analysis. Effectiveness was expressed as the number of HIV-1 or HCV infections detected, regardless of whether they were related to transfusion. To estimate costs, we assumed hospital insurance would cover costs related to detection and compensation, when granted.

Setting:

A 2,890-bed acute care teaching hospital in Bordeaux, France.

Methods:

Eight options were defined, from the simplest, which would be to do nothing, to a maximal approach, which would be to keep a serum sample in a serum library for a lookback and perform tests for antibody to HIV-1 and to HCV before and 3 months after transfusion. Data on probabilities and costs were taken from the literature and experiences of French hospitals.

Results:

The most cost-effective option was to perform viral antibody testing before transfusions (option 3), which would detect 27 infections per 1,000 patients, for an expenditure of US $1,260 per detected patient Option 6, obtaining a serum sample before transfusion and performing tests for antibody to HIV-1 and to HCV 3 months after transfusion, had a similar cost-effectiveness ratio but detected only 16 infections per 1,000 patients. Performing tests before and 3 months after transfusion (option 4), compared with option 3, would detect 1 additional infection for an additional cost of US $8,322.

Conclusion:

The most cost-effective options are not specific to blood transfusion recipients and might be more suited to all hospitalized patients.

Cerebral and peripheral near-infrared spectroscopy: an alternative transfusion trigger?

BACKGROUND AND OBJECTIVES

To develop a transfusion trigger based on tissue oxygenation, near-infrared spectroscopy (NIRS) was evaluated in a model of compensated haemorrhage.

PATIENTS AND METHODS

Regional haemoglobin oxygen saturation from the cerebral cortex (CsO2) and the gastrocnemius muscle (PsO2) was monitored (using an INVOS 4100 near-infrared oximeter) in 30 patients during acute normovolaemic haemodilution to a target haemoglobin of 11 g/dl. Arterial oxygen saturation, end-tidal carbon dioxide tension, mean arterial pressure and haemoglobin concentration were also measured.

RESULTS

During blood collection, CsO2 and PsO2 fell by a mean (95% CI) of 8 (5.3-10.7)% (P < 0.001) and 5.5 (3.2-7.8)% (P < 0.001), respectively. Arterial pressure and oxygen saturation did not change, whilst the end-tidal carbon dioxide tension fell by 2.3 (0.8-3.8) mmHg (P = 0.004). Haemoglobin concentration correlated with CsO2 (R = 0.76, P < 0.001) and PsO2 (R = 0.63, P < 0.001), as did the volume of blood removed.

CONCLUSIONS

CsO2 and PsO2 fell predictably during compensated blood loss. With further research, NIRS may be developed into a transfusion trigger.

Identifying patients for blood conservation strategies

BACKGROUND

Generally, only the type of operation is used to estimate the need for perioperative homologous blood transfusion. This study quantified the extent to which the estimation could be improved if, in addition, simple patient characteristics were taken into account.

METHODS

Retrospective data on 24 509 consecutive adult surgical patients were used to derive and validate three models to predict perioperative homologous transfusion. The first model was a univariable model with type of operation as the only predictor. The second and third models were a full and a simplified multivariable logistic regression model. The performance of the multivariable models was tested in two validation sets: in similar patients who had operations in the same general hospital (internal validation) and in patients who had operations in a university hospital (external validation). The areas under the receiver-operator characteristic (ROC) curve were compared with that found in the derivation set.

RESULTS

There were no important differences in characteristics between the derivation and validation sets. The ROC area of the model including surgery only was 0.92 (99 per cent confidence interval (c.i.) 0.91 to 0.94) and that of the full and simplified multivariable models 0.95 (99 per cent c.i. 0.94 to 0.96) and 0.94 (99 per cent c.i. 0.93 to 0.95) respectively. The latter two were significantly different from the first one. In the external validation set the ROC area of the simplified model was 0.84 (95 per cent c.i. 0.83 to 0.86). Patients who had a preoperative haemoglobin level lower than 13 g/dl and underwent major invasive surgery had the highest risk (43 per cent) of transfusion.

CONCLUSION

A simple algorithm using type of operation and haemoglobin concentration was effective in identifying patients likely to need perioperative homologous blood transfusion.

Residual risk of transfusion-transmitted HCV and HIV infections by antibody-screened blood in Italy

BACKGROUND

This study was designed to assess the risk of transmitting HCV and HIV by transfusion of antibody-screened blood and to estimate the additional reduction in risk that may be achieved through the implementation of direct viral detection assays in Italy.

STUDY DESIGN AND METHODS

Clinical and laboratory data of 2,411,800 blood donations collected from repeat volunteer donors from 1996 through 2000 were analyzed. The risk of transmitting HCV or HIV from screened blood donated during the window period was estimated using a mathematical model.

RESULTS

The residual risk of donating antibody-negative infectious blood was estimated at 1 in 127,000 donations for HCV and 1 in 435,000 for HIV. The use of NAT should further reduce such risk by 83 percent for HCV and 50 percent for HIV.

CONCLUSION

The residual risk of HCV or HIV transmission through screened blood is currently very small in Italy. The implementation of direct viral detection assays can further improve the safety of blood supply.

An estimate of the current risk of transmitting blood-borne infections through blood transfusion in Italy

We conducted a retrospective cohort study to estimate the incidence of major blood-borne agents among Italian blood donors and calculated the risk of infection among blood recipients using the 'incidence/window period model'. The study was conducted among 46 180 blood donors enrolled in six blood centres between 1994 and 1999. During follow-up, seven new infections were confirmed: three donors seroconverted for anti-human immunodeficiency virus (HIV); two for anti-hepatitis C virus (HCV); and two showed hepatitis B surface antigen (HBsAg) reactivity; no cases of syphilis were observed. The incidence rates per 100 000 person/years were: 4.06 (95% CI: 0.82-11.85) for HIV; 2.41 (95% CI: 0.29-8.70) for HCV; and 2.70 (95% CI: 0.32-9.77) for HBsAg; the incidence for total hepatitis B virus (HBV) infection was 9.77 per 100 000 person/years (95% CI: 1.16-35.36). The estimated risk of an infectious blood unit not being detected was: 2.45 (95% CI: 0.13-12.33) per 1 million units for HIV; 4.35 (95% CI: 0.30-22.39) for HCV; and 15.78 (95% CI: 1.16-84.23) for HBV. Overall, an estimated 22.58 per 1 million units are infected. In Italy, the risk of transfusion-transmitted infections is low and is similar to that in other western countries. The introduction of new more sensitive screening tests could reduce the residual risk of transfusion-transmitted infection by 40-80%.