Three years of haemovigilance in a general university hospital

Review of haemovigilance at the Rabat Regional Blood Transfusion Centre in Morocco (2017-2021)

Introduction

blood transfusion remains an essential therapeutic intervention, but the occurrence of transfusion reactions makes its administration even more complex. Vigilant reporting of such reactions by recipients of blood products is essential for effective haemovigilance. This study aimed to determine the frequency and nature of transfusion reactions.

Methods

conducted over five years (2017-2021) at the Haemovigilance Department of the Rabat Regional Blood Transfusion Centre, this retrospective study exploited incident forms notified by health establishments and data from the regional blood transfusion centre's computer system.

Results

from 1 January 2017 and 31 December 2021, the Rabat Regional Blood Transfusion Centre distributed 435,651 labile blood products to various healthcare establishments, which reported 191 transfusion reactions involving 191 patients. The median age of the patients was 44.3 years, with an overall cumulative incidence of transfusion reactions of 0.44 per 1000 labile blood products delivered. The predominant reactions were non-haemolytic febrile and allergic reactions, accounting for 41.36% and 35.60% respectively. Grade 1 reactions accounted for 87% of all reactions recorded. During the study period, three deaths were recorded, with ABO incompatibility and transfusion-related acute lung injury (TRALI) accounting for two and one case respectively. Transfusion reactions involving erythrocyte components were significantly more frequent than those involving platelet and plasma components.

Conclusion

this study revealed a relatively low incidence of transfusion reactions (0.44%), dominated by non-haemolytic febrile and allergic reactions. Several levels of failure were identified, in particular under-reporting of reactions and inadequate training in transfusion practices and haemovigilance, as well as the need for an effective electronic transfusion reaction reporting system to facilitate reporting and identification of underlying problems and risk factors to improve the quality of transfusion care provided to patients.

The incidence of transfusion-related acute lung injury using active surveillance: A systematic review and meta-analysis

BACKGROUND

Transfusion-related acute lung injury (TRALI) is a leading cause of transfusion-related mortality. A concern with passive surveillance to detect transfusion reactions is underreporting. Our aim was to obtain evidence-based estimates of TRALI incidence using meta-analysis of active surveillance studies and to compare these estimates with passive surveillance.

STUDY DESIGN AND METHODS

We performed a systematic review and meta-analysis of studies reporting TRALI rates. A search of Medline and Embase by a research librarian identified studies published between January 1, 1991 and January 20, 2023. Prospective and retrospective observational studies reporting TRALI by blood component (red blood cells [RBCs], platelets, or plasma) were identified and all inpatient and outpatient settings were eligible. Adult and pediatric, as well as general and specific clinical populations, were included. Platelets and plasma must have used at least one modern TRALI donor risk mitigation strategy. A random effects model estimated TRALI incidence by blood component for active and passive surveillance studies and heterogeneity was examined using meta-regression.

RESULTS

Eighty studies were included with approximately 176-million blood components transfused. RBCs had the highest number of studies (n = 66) included, followed by platelets (n = 35) and plasma (n = 34). Pooled TRALI estimates for active surveillance studies were 0.17/10,000 (95% confidence intervals [CI]: 0.03-0.43; I2  = 79%) for RBCs, 0.31/10,000 (95% CI: 0.22-0.42; I2  = <1%) for platelets, and 3.19/10,000 (95% CI: 0.09-10.66; I2  = 86%) for plasma. Studies using passive surveillance ranged from 0.02 to 0.10/10,000 among the various blood components.

DISCUSSION

In summary, these estimates may improve a quantitative understanding of TRALI risk, which is important for clinical decision-making weighing the risks and benefits of transfusion.

A Retrospective Analysis of Transfusion Reactions at a Tertiary Care Center: An Institutional Hemovigilance Study

BACKGROUND

The goal of our study was to determine the frequency and type of transfusion reactions (TRs) as well as other hemovigilance activities reported at a tertiary care hospital in Turkey over a period of 3 years.

METHOD

In this retrospective study, the notification sheets of TRs reported to the institution's local hemovigilance system between December 2017 and December 2020 were analyzed.

RESULTS

A total of 89,187 units of blood components were administered to patients during this period. A total of 197 TRs were reported to the hemovigilance system. The overall frequency of TRs was 0.22%. The most common TRs were allergic reactions (49.2%) and febrile nonhemolytic transfusion reactions (37.6%), respectively. Most of the adverse events were reported by clinical nurses.

CONCLUSION

Our study showed that the frequency of TRs was low, and most were manageable reactions. We found that reporting of all TRs and continuous nursing education can help to strengthen the hemovigilance system. [J Contin Educ Nurs. 2021;52(12):581-588.].

Surveillance of Transfusion Related Adverse Reactions in a Tertiary Care Centre in Bangalore: A 4-Year Hemovigilance Initiative

Even though blood transfusion is a life saving measure, it is nonetheless associated with a number of risks and hazards. The adverse reactions that can be potentially expected range anywhere in severity from mild to life threatening. The hemovigilance program deals with the systematic surveillance of these reactions as and when they occur in a hospital setting with an explicit aim of improving the quality and safety standards of the entire transfusion process. The current study was undertaken in the blood bank of a tertiary care centre in Bangalore to ascertain frequency of the blood transfusion related adverse reactions and to make a systematic profile assessment. Data was collected over a period of 4 years and 3 months. All adverse reactions caused by transfusion of blood and its products during the study period were included in the study. A total of 6910 units of blood and its components were issued to patients during the study period. Transfusion reactions accounted for 0.5% of transfusions. Febrile non-hemolytic transfusion reactions were the most common reactions (51.4%) followed by allergic reactions (40%), fluid overload (5.7%) and anaphylactic reactions (2.9%). Majority of these reactions were seen with PRBC transfusions (74.3%) followed by platelet transfusions (25.7%). The use of leukoreduced PRBCs will help in reducing the frequency of these reactions. The hemovigilance program of our institution helps in assessing the diversity of adverse reactions associated with transfusion of blood and its various components. It is also an efficient scheme for minimizing their occurrence by ensuring safety standards.

Transfusion reactions: A retrospective analysis of the Iranian national haemovigilance system (INHS) data

BACKGROUND

The use of blood and blood components is an essential and effective treatment for many patients, but the transmission of infectious agents via transfusion and the occurrence of non-infectious transfusion reactions (TRs) are unavoidable. The objective of our study was to determine the frequency and type of transfusion-related reactions reported in Iran between 2014 and 2018.

METHODS

This retrospective study was carried out in the Iranian blood transfusion organization (IBTO) during a period of five years (2014-2018). All TRs reported to the Iranian national haemovigilance system (INHS) were analyzed using SPSS software.

RESULTS

A total of 20,062 TRs were reported to the INHS from 2014 to 2018. The overall frequency of TRs was 0.14 %. The most common TRs were allergic (42.51 %) and febrile non-hemolytic reactions (37.17 %), respectively. The frequency of TRs to red blood cell (RBC) components was significantly higher than those to the components of platelet (PLT) and plasma (P < 0.05).

CONCLUSIONS

In the present study, the frequency of TRs was relatively low (0.14 %) and the majority of them were allergic and febrile non-hemolytic reactions. The recording and reporting of all occurred TRs, the implementation of INHS in all hospitals and the continuity of specific educational courses to physicians, nurses and blood banking staff, as well as the use of an online reporting system will help to improve the haemovigilance in Iran.

Hemovigilance: the experience of transfusion reaction reporting in a Teaching Hospital

OBJECTIVE

To describe the occurrence of immediate transfusion reactions received by the Risk Management Department of Hospital São Paulo.

METHOD

Cross-sectional and retrospective study which analyzed the notification sheets of transfusion reactions that occurred between May 2002 and December 2016 and were included in the Hemovigilance National System.

RESULTS

One thousand five hundred and forty-eight transfusion reaction notification sheets were analyzed, all of which concerned immediate reactions associated with packed red blood cells (72.5%). The most frequently reported reaction was febrile non-hemolytic transfusion reaction, and among severe and moderate cases, allergic reaction was the most common. The most frequently reported signs and symptoms were hyperthermia, sudoresis, chills, and skin lesions. No differences were observed regarding gender and age, and 90.7% of reactions occurred in patients with Rh+ factor.

CONCLUSION

This study allowed for a better assessment and understanding of transfusion reactions, which will help to improve the quality of blood circulation and provide greater safety of patients undergoing transfusion therapy.

Reporting adverse transfusion reactions: A retrospective study from tertiary care hospital from New Delhi, India

CONTEXT:

Blood transfusion services have achieved newer heights in the last decade, with developments in cellular techniques, component separation, and integration of molecular methods. However, the system of recording and reporting of the adverse events related to blood transfusion is developing countries like India is grossly inadequate and voluntary in nature.

AIMS:

This study was undertaken to analyze the retrospective data on adverse events related to blood transfusions in our hospital.

SUBJECTS AND METHODS:

This retrospective study was done to examine all the transfusion related adverse events reported in a Regional Blood Bank Transfusion Centre of North India over a period of 9 years. Adverse transfusion events related to whole blood, red cell concentrates (RCCs), and all other components were analyzed and classified on the basis of their clinical features and laboratory tests. Average rate of transfusion reactions with the components was also assessed.

STATISTICAL ANALYSIS USED:

Categorical variables were analyzed using the Chi-square test. P < 0.05 was taken to indicate a significant difference.

RESULTS:

During this period, a total of 1,60,973 blood/blood component units were issued by our blood bank to various departments of the hospital and 314 immediate transfusion events were reported. The rate of immediate transfusion reactions during the study was 0.19%. Average transfusion reaction rate with RCC was 0.25% with febrile nonhemolytic reactions being the most common type of adverse event (37.2%).

CONCLUSIONS:

Awareness should be increased among clinicians to correctly prevent, identify, and report transfusion-related adverse events. These measures should be implemented to increase blood transfusion quality and safety.

[Recipients adverse reactions in the Ibn Sina Hospital of Rabat: State 1999-2013]

PURPOSE OF STUDY

The declaration of the recipients adverse reactions (RAR) is one of the field haemovigilance activities. It provides an evaluation of transfusion side effects and thus prevents their appearance. The aim of this study is to analyze, over 14 years, the RAR supports reported in Rabat Ibn Sina hospital.

PATIENTS AND METHODS

All of the RAR supports sending to the blood transfusion service were analyzed. The data collected from these supports are: clinical characteristics of the patient, type of incident observed and type of labile blood products (LBP) transfused.

RESULTS

A total of 353 RAR were declared with a mean cumulative incidence of 1.7/1000 LBP delivered. Febrile non-hemolytic transfusion reactions represent 72.8% of the RAR declared. The RAR were classified as grade 1 in 87.1% of cases and were secondary to a transfusion of the red cell concentrates in 81.9%. ABO incompatibility was found in four cases (0.02/1000 LBP delivered).

CONCLUSION

The number of RAR reported by Rabat Ibn Sina hospital remains underestimated. Management and traceability RAR and rigorous investigation, under the responsibility of the corresponding haemovigilance contribute to the improvement of transfusion safety.

Study of acute transfusion reactions in a teaching hospital of Sikkim: A hemovigilance initiative

Objective:

Blood transfusions are inherently associated with risks ranging in severity from minor to life-threatening. Continuous monitoring of transfusion related complications can promote understanding of factors contributing to transfusion reactions and help to formulate necessary remedial measures. This study was designed to analyze the frequency and nature of transfusion reactions reported to the blood bank of a remote North East Indian teaching hospital.

Materials and Methods:

All acute transfusion reactions (ATRs) reported to the blood bank over a period of 20 months (May 2013 to January 2015) were reviewed and analyzed. The risk of transfusion reactions associated with each individual component was assessed.

Results:

A total of 3455 units of whole blood and component transfusions were carried out of which a total of 32 (0.92%) ATRs were encountered. Packed red blood cells (PRBCs) (n = 15, P = 0.06) and whole blood (WB) (n = 13, P = 0.83) were most commonly implicated. Allergic reaction was the most frequent transfusion reaction encountered (65.6%), seen most commonly with PRBC (risk of 0.76%, P = 0.42), and WB (risk of 0.68%, P = 0.63) transfusions. This was followed by febrile reactions (28.1%), which were seen more commonly with PRBCs (risk of 0.57%, P = 0.016). No reactions were observed with platelet transfusions.

Conclusion:

The overall incidence of transfusion reactions in this hospital is slightly higher than those having more advanced transfusion facilities in India. The lack of leukoreduction facilities in our hospital could be a likely cause for the same. The use of leukoreduced WB and PRBCs could possibly reduce the overall incidence of ATRs in general and febrile nonhemolytic transfusion reactions in particular.

Incidence and pattern of 12 years of reported transfusion adverse events in Zimbabwe: a retrospective analysis

BACKGROUND

Haemovigilance hinges on a systematically structured reporting system, which unfortunately does not always exist in resource-limited settings. We determined the incidence and pattern of transfusion-related adverse events reported to the National Blood Service Zimbabwe.

MATERIALS AND METHODS

A retrospective review of the transfusion-event records of the National Blood Service Zimbabwe was conducted covering the period from 1 January 1999 to 31 December 2011. All transfusion-related event reports received during the period were analysed.

RESULTS

A total of 308 transfusion adverse events (0.046%) were reported for 670,625 blood components distributed. The majority (61.6%) of the patients who experienced an adverse event were female. The median age was 36 years (range, 1-89 years). The majority (68.8%) of the adverse events were acute transfusion reactions consisting of febrile non-haemolytic transfusion reactions (58.5%), minor allergies (31.6%), haemolytic reactions (5.2%), severe allergic reactions (2.4%), anaphylaxis (1.4%) and hypotension (0.9%). Two-thirds (66.6%) of the adverse events occurred following administration of whole blood, although only 10.6% of the blood was distributed as whole blood. Packed cells, which accounted for 75% of blood components distributed, were associated with 20.1% of the events.

DISCUSSION

The incidence of suspected transfusion adverse events was generally lower than the incidences reported globally in countries with well-established haemovigilance systems. The administration of whole blood was disproportionately associated with transfusion adverse events. The pattern of the transfusion adverse events reported here highlights the probable differences in practice between different settings. Under-reporting of transfusion events is rife in passive reporting systems.

Analysis of immediate transfusion incidents reported in a regional blood bank

BACKGROUND

Blood transfusion is imperative when treating certain patients; however, it is not risk free. In addition to the possible transmission of contagious infectious diseases, incidents can occur immediately after transfusion and at a later time.

AIMS

This study aimed to examine the immediate transfusion incidents reported in a regional blood bank in the state of Minas Gerais between December 2006 and December 2009. A retrospective quantitative epidemiological study was conducted. Data were obtained from 202 transfusion incident reports of 42 health institutions served by the blood bank. Data processing and analysis were carried out using the Statistical Package for the Social Sciences (SPSS) software.

RESULTS

The rate of immediate transfusion incidents reported in the period was 0.24%; febrile non-hemolytic reactions were the most common type of incident (56.4%). The most frequent clinical manifestations listed in transfusion incident reports were chills (26.9%) and fever (21.6%). There was a statistically significant association (p-value < 0.05) between the infusion of platelet concentrates and febrile non-hemolytic reactions and between fresh frozen plasma and febrile non-hemolytic reaction. The majority (73.3%) of transfused patients who suffered immediate transfusion incidents had already been transfused and 36.5% of the cases had previous transfusion incident reports.

CONCLUSIONS

Data from the present study corroborate the implementation of new professional training programs aimed at blood transfusion surveillance. These measures should emphasize prevention, identification and reporting of immediate transfusion incidents aiming to increase blood transfusion quality and safety.

Incidentes transfusionais imediatos: revisão integrativa da literatura

Este estudo de revisão integrativa da literatura teve como objetivo analisar as pesquisas que abordam a ocorrência de incidentes transfusionais imediatos e ações de hemovigilância implantadas. Os dados foram obtidos por meio de busca nas bases de dados - LILACS, MEDLINE e PUBMED - abrangendo o período de 1980 a 2009, nos idiomas português, inglês e espanhol. Foram identificados 1.382 artigos, dos quais 29 atenderam aos critérios de inclusão estabelecidos. Destes artigos, 20 (69,0%) eram estudos retrospectivos transversais, 8 (27,5%) prospectivos e um (3,5%) caso-controle. Em relação à abordagem, os estudos foram classificados em dois focos temáticos: tipos de incidentes transfusionais imediatos e ações de hemovigilância implantadas associadas aos tipos de incidentes transfusionais imediatos. A análise dos trabalhos destacou a maior ocorrência de reação febril não hemolítica e alérgica, avanço em ações de hemovigilância e maior preocupação com a qualidade da assistência hemoterápica.

A well-designed online transfusion reaction reporting system improves the estimation of transfusion reaction incidence and quality of care in transfusion practice

Recognizing and reporting a transfusion reaction is important in transfusion practice. However, the actual incidence of transfusion reactions is frequently underestimated. We designed an online transfusion reaction reporting system for nurses who take care of transfusion recipients. The common management before and after transfusion and the 18 most common transfusion reactions were itemized as tick boxes. We found the overall documented incidence of transfusion reaction increased dramatically, from 0.21% to 0.61% per unit of blood, after we started using an online reporting system. Overall, 94% (30/32) of nurses took only 1 week to become familiar with the new system, and 88% (28/32) considered the new system helpful in improving the quality of clinical transfusion care. By using an intranet connection, blood bank physicians can also identify patients who are having a reaction and provide appropriate recommendations immediately. A well-designed online reporting system may improve the ability to estimate the incidence of transfusion reactions and the quality of transfusion care.

A randomised controlled pilot trial to evaluate and optimize the use of anti-platelet agents in the perioperative management in patients undergoing general and abdominal surgery--the APAP trial (ISRCTN45810007)

PURPOSE

Surgeons are increasingly confronted by patients on long-term low-dose acetylsalicylic acid (ASA). However, owing to a lack of evidence-based data, a widely accepted consensus on the perioperative management of these patients in the setting of non-cardiac surgery has not yet been reached. Primary objective was to evaluate the safety of continuous versus discontinuous use of ASA in the perioperative period in elective general or abdominal surgery.

METHODS

Fifty-two patients undergoing elective cholecystectomy, inguinal hernia repair or colonic/colorectal surgery were recruited to this pilot study. According to cardiological evaluation, non-high-risk patients who were on long-term treatment with low-dose ASA were eligible for inclusion. Patients were allocated randomly to continuous use of ASA or discontinuation of ASA intake for 5 days before until 5 days after surgery. The primary outcome was the incidence of major haemorrhagic and thromboembolic complications within 30 days after surgery.

RESULTS

A total of 26 patients were allocated to each study group. One patient (3.8%) in the ASA continuation group required re-operation due to post-operative haemorrhage. In neither study group, further bleeding complications occurred. No clinically apparent thromboembolic events were reported in the ASA continuation and the ASA discontinuation group. Furthermore, there were no significant differences between both study groups in the secondary endpoints.

CONCLUSIONS

Perioperative intake of ASA does not seem to influence the incidence of severe bleeding in non-high-risk patients undergoing elective general or abdominal surgery. Further, adequately powered trials are required to confirm the findings of this study.

[Pathogen reduction of blood components: from financial issues to possible long-term consequences]

Pathogen inactivation of blood products represents a global and major paradigm shift in transfusion medicine. In the next near future, it is likely that most blood products will be inactivated by various physicochemical approaches. The concept of blood safety will be challenged as well as transfusion medicine practice, notably for donor selection or biological qualification. In this context, it seems mandatory to develop analytical economic approaches by assessing costs-benefits ratio of blood transfusion as well as to set up cohorts of patients based on hemovigilance networks allowing rigorous scientific analysis of the benefits and the risks of blood transfusion at short- and long-term.

A review of the use of common antiplatelet agents in orthopaedic practice

Antiplatelet agents are widely prescribed for the primary and secondary prevention of cardiovascular events. A common clinical problem facing orthopaedic and trauma surgeons is how to manage patients receiving these agents who require surgery, either electively or following trauma. The dilemma is to balance the risk of increased blood loss if the antiplatelet agents are continued peri-operatively against the risk of coronary artery/stent thrombosis and/or other vascular event if the drugs are stopped. The traditional approach of stopping these medications up to two weeks before surgery appears to pose significant danger to patients and may require review. This paper covers the important aspects regarding the two most commonly prescribed antiplatelet agents, aspirin and clopidogrel.

Perioperative handling of patients on antiplatelet therapy with need for surgery

The widespread use of metal stents and drug-eluting stents has shown the extent to which patients with unstable coronary perfusion depend on antiplatelet drugs, and how their risk of late thrombosis depends on the long-term use of agents such as clopidogrel. It has also been shown that the risk of surgical bleeding, if antiplatelet drugs are continued, is lower than that of coronary thrombosis if they are withdrawn. Thus, except for low-risk settings, the practice of withdrawing antiplatelet drugs 5-10 days prior to surgical procedures should be changed. The following suggestions are meant to provide a guideline in this respect. Most of the current surgical procedures may be performed while on low-dose aspirin treatment. Except when bleeding may occur in closed spaces (e.g. intracranial surgery, spinal surgery in the medullary canal, surgery of the posterior chamber of the eye) or where excessive blood loss is expected, where only clopidogrel should be discontinued; in all other cases the surgical procedures should be carried out in the presence of dual antiplatelet agents (if prescribed). Aspirin may be discontinued only in subjects at low risk of thrombosis, and at high risk of intraoperative bleeding. Operations associated with an expected excessive blood loss should be postponed unless vital. When prescribed for acute coronary syndrome or during stent re-endothelialization, clopidogrel should not be discontinued before a noncardiac procedure. For elective procedures, surgery should be postponed until the end of the indication for clopidogrel. After the operation, clopidogrel should be resumed within the 12-24 h. Cardiac procedures should be postponed for at least 4 days after clopidogrel withdrawal. The thrombotic risk of preoperative withdrawal of antiplatelet drugs overwhelms the benefit of regional or neuraxial blockade. Antiplatelet treatment replacement by heparin or low-molecular weight heparin does not provide protection against the risk of coronary artery or stent thrombosis. Haemostasis requires that at least 20% of circulating platelets have a normal function. As the effects of antiplatelet agents are not reversible by other drugs, fresh platelets are the only manner to rapidly restore normal haemostasis. Aprotinin decreases postoperative bleeding and transfusion rates in patients undergoing CABG and on clopidogrel during the days preceding surgery.

Designing property specifications to improve the safety of the blood transfusion process

Computer scientists use a number of well-established techniques that have the potential to improve the safety of patient care processes. One is the formal definition of a process; the other is the formal definition of the properties of a process. Even highly regulated processes, such as laboratory specimen acquisition and transfusion therapy, use guidelines that may be vague, misunderstood, and hence erratically implemented. Examining processes in a systematic way has led us to appreciate the potential variability in routine health care practice and the impact of this variability on patient safety in the clinical setting. The purpose of this article is to discuss the use of innovative computer science techniques as a means of formally defining and specifying certain desirable goals of common, high-risk, patient care processes. Our focus is on describing the specification of process properties, that is, the high-level goals of a process that ultimately dictate why a process should be performed in a given manner.

Swiss Haemovigilance Data and Implementation of Measures for the Prevention of Transfusion Associated Acute Lung Injury (TRALI)

SUMMARY: In Switzerland, blood donations are collected exclusively from healthy non-remunerated voluntary blood donors mainly by 13 regional Blood Transfusion Services throughout the country. Thereby, self-sufficient blood supply for a population of about 7.5 million is achieved, and approximately 300,000 units of red cells, 75,000 therapeutic units of fresh plasma, and 20,000 therapeutic units of platelets are transfused annually. Reporting to Swissmedic (the Swiss agency for therapeutic products) of all suspected adverse transfusion events on a standardised form is mandatory. Data are then analysed to estimate the risks of the most serious transfusion events. Together with transfusion of an incorrect blood component and bacterial contamination of platelet concentrates, TRALI is a significant risk of transfusion in Switzerland and occurs in approximately every 8,000-20,000 FFP transfusions according to current haemovigilance data. Among 25 reported cases between 2002 and November 2007, 4 are proven immune TRALI, 2 are highly likely immune TRALI, 10 are possibly immune TRALI, 8 are non-immune TRALI, and 1 is a suspected case which could not be confirmed as TRALI. Based on the hypothesis of an immunological trigger of TRALI, an exclusion of the transfusion of plasma from female donors can be considered as a precautionary measure which might have prevented 4 cases of proven immune TRALI, 2 cases of highly likely immune TRALI, and an unknown number of the 10 cases of possibly immune TRALI. Based on these data and encouraging preliminary reports of the effects of comparable measures in other countries, the decision was made that starting with January 1st 2007 the production of quarantined FFP is restricted to donations from men or from women confirming that they have never been pregnant (to their knowledge) or with negative tests for antibodies against HLA class I and II. The analysis of further vigilance data is needed to elucidate the efficacy of this preventive measure.

Perioperative antiplatelet therapy: the case for continuing therapy in patients at risk of myocardial infarction

Recent clinical data show that the risk of coronary thrombosis after antiplatelet drugs withdrawal is much higher than that of surgical bleeding if they are continued. In secondary prevention, aspirin is a lifelong therapy and should never be stopped. Clopidogrel is regarded as mandatory until the coronary stents are fully endothelialized, which takes 3 months for bare metal stents, but up to 1 yr for drug-eluting stents. Therefore, interruption of antiplatelet therapy 10 days before surgery should be revised. After reviewing the data on the use of antiplatelet drugs in cardiology and in surgery, we propose an algorithm for the management of patients, based on the risk of myocardial ischaemia and death compared with that of bleeding, for different types of surgery. Even if large prospective studies with a high degree of evidence are still lacking on different antiplatelet regimens during non-cardiac surgery, we propose that, apart from low coronary risk situations, patients on antiplatelet drugs should continue their treatment throughout surgery, except when bleeding might occur in a closed space. A therapeutic bridge with shorter-acting antiplatelet drugs may be considered.

Perioperative use of anti-platelet drugs

Performing a surgical procedure on a patient undergoing anti-platelet therapy raises a dilemma: is it safer to withdraw the drugs and reduce the haemorrhagic risk, or to maintain them and reduce the risk of myocardial ischaemic events? Based on recent clinical data, this review concludes that the risk of coronary thrombosis on anti-platelet drugs withdrawal is much higher than the risk of surgical bleeding when maintaining them. In secondary prevention, aspirin is a lifelong therapy and should never be stopped. Clopidogrel is mandatory as long as the coronary stents are not fully endothelialized, which takes 6-24 weeks depending on the technique used, but might be required for a longer period.

Increasing patient safety and efficiency in transfusion therapy using formal process definitions

The administration of blood products is a common, resource-intensive, and potentially problem-prone area that may place patients at elevated risk in the clinical setting. Much of the emphasis in transfusion safety has been targeted toward quality control measures in laboratory settings where blood products are prepared for administration as well as in automation of certain laboratory processes. In contrast, the process of transfusing blood in the clinical setting (ie, at the point of care) has essentially remained unchanged over the past several decades. Many of the currently available methods for improving the quality and safety of blood transfusions in the clinical setting rely on informal process descriptions, such as flow charts and medical algorithms, to describe medical processes. These informal descriptions, although useful in presenting an overview of standard processes, can be ambiguous or incomplete. For example, they often describe only the standard process and leave out how to handle possible failures or exceptions. One alternative to these informal descriptions is to use formal process definitions, which can serve as the basis for a variety of analyses because these formal definitions offer precision in the representation of all possible ways that a process can be carried out in both standard and exceptional situations. Formal process definitions have not previously been used to describe and improve medical processes. The use of such formal definitions to prospectively identify potential error and improve the transfusion process has not previously been reported. The purpose of this article is to introduce the concept of formally defining processes and to describe how formal definitions of blood transfusion processes can be used to detect and correct transfusion process errors in ways not currently possible using existing quality improvement methods.

Haemovigilance in a general university hospital: need for a more comprehensive classification and a codification of transfusion-related events

BACKGROUND AND OBJECTIVES

The purpose of this study was to analyse the transfusion-related events recorded in a general university hospital.

MATERIALS AND METHODS

The method we used was retrospective analysis of the data collected between 1999 and 2003.

RESULTS

The incidence of transfusion reactions (n = 394) was 4.19 per 1000 blood products distributed: 59% (n = 231) were febrile non-haemolytic transfusion reactions; 22% (n = 88) were caused by allergy; 5% (n = 21) were caused by bacterial infection; and 14% (n = 54) were classified as other reactions. Platelet concentrates gave rise to a significantly greater number of reactions than erythrocyte concentrates and fresh-frozen plasma. Transfusion errors and near-miss events were also observed and were analysed separately. A series of transfusion-related events, such as haemosiderosis, metabolic disturbances or volume overload, were not reported.

CONCLUSIONS

Our experience prompts us to propose a more comprehensive classification and codification of transfusion-related events.

Strategies for transfusion therapy

Transfusion of allogeneic red blood cells (RBCs), fresh frozen plasma (FFP) and platelets is associated with risks, and outcome studies comparing liberal and restrictive transfusion regimens are lacking in surgical patients. Therefore, guidelines have been established. They recommend first maintaining normovolaemia by the use of crystalloids and colloids. RBC transfusions are recommended for haemoglobin levels < 6 g/dl and for physiological signs of inadequate oxygenation such as haemodynamic instability, oxygen extraction > 50% and myocardial ischaemia (new ST-segment depressions > 0.1 mV, new ST-segment elevations > 0.2 mV or new wall motion abnormalities in transoesophageal echocardiography). FFP transfusions are recommended for urgent reversal of anticoagulation, known coagulation factor deficiencies, microvascular bleeding in the presence of elevated (> 1.5 times normal) prothrombin time (PT) or partial thromboplastin time (PTT) and microvascular bleeding after the replacement of more than one blood volume when PT or PTT cannot be obtained. Platelet transfusions are recommended prior to major operations in patients with platelet counts < 50,000/microl, intraoperatively with microvascular bleeding at platelet counts < 50,000/microl and in the range of 50,000-100,0000/microl following cardiopulmonary bypass and in patients undergoing surgery where already minimal bleeding may cause major damage such as in neurosurgery.

Updates in perioperative coagulation: physiology and management of thromboembolism and haemorrhage

Understanding of blood coagulation has evolved significantly in recent years. Both new coagulation proteins and inhibitors have been found and new interactions among previously known components of the coagulation system have been discovered. This increased knowledge has led to the development of various new diagnostic coagulation tests and promising antithrombotic and haemostatic drugs. Several such agents are currently being introduced into clinical medicine for both the treatment or prophylaxis of thromboembolic disease and for the treatment of bleeding. This review aims to elucidate these new concepts and to outline some consequences for clinical anaesthesia and perioperative medicine.