Use of red blood cell transfusions in surgery.

BACKGROUND: Limited blood supplies necessitate the rational use of blood products. The aim of the present study was to provide a basis for audits of red cell usage in surgery by benchmarking common practice. Application of the data to the construction of a maximum surgical blood order schedule may be relevant for centres that perform a serological crossmatch or who collect autologous units. METHODS: Data on surgical procedures identified by Commonwealth Medical Benefits Schedule item numbers, were collected retrospectively from theatre and blood bank records at the Royal Melbourne and Melbourne Private hospitals from May 1997 to April 1998. The percentage of procedures for which red cells were transfused, and the mean, median and range of units transfused for procedures with >/= 30% transfusion likelihood were identified. RESULTS: Over 12 months, 266 surgical procedure codes were itemized >/= 10 times each, contributing 12 300 data entries. Only 38 procedures demonstrated an incidence of transfusion of at least 30%. Most frequently transfused procedures included spinal fusion, total hip replacement, mandible/maxilla resection, prostatectomy and bladder excision. CONCLUSION: The number of common surgical procedures in which there is a 30% or greater likelihood that red cell transfusions will be given is limited. This benchmarking of common red cell usage is a first step in the process of determination of transfusion appropriateness.

[Labile blood products and their preparation]. / Produits sanguins labiles et leur préparation.

Licensed labile blood components are put down on a regulatory list by the French Health Authority. They are prepared by the French National Blood Service and controlled according to regulatory and validated procedures. Depending on the origin of the blood, labile blood components are either homologous (donors) or autologous (from patients). Blood components (red cell concentrates, platelet concentrates and fresh frozen plasma) are processed within sterile closed disposable systems using either post-donation processing of whole blood or apheresis technology. All homologous blood components are leuco-reduced. Depending on specific settings, blood components could be washed, gamma irradiated or cryopreserved. Fresh frozen plasma is either "donor retested" after quarantine or viro-attenuated by solvent detergent treatment. Release is only allowed after a full conformity control of each blood component unit.

Safety of the blood supply.

Three of four recipients of transfusion in the United States are patients undergoing surgery, and despite promising advances in the development of alternatives to allogeneic blood transfusion, it is likely that for years to come this patient population will remain dependent on blood donated by volunteers. The safety of the blood supply has been questioned seriously since it became known that the human immunodeficiency virus could be transmitted by transfusion. In response to this threat, enforcement of strict donor eligibility criteria, removal of high risk donors from the donor pool, and testing of each donation with a panel of viral markers were instituted which have reduced the infectious risks of allogeneic blood transfusion dramatically during the last decade. The current safety of the blood supply is reviewed and the ongoing efforts to improve the safety of transfusions in the future are summarized briefly.

Review of the problems involved in using enzymes in blood group serology--provision of freeze-dried ICSH/ISBT protease enzyme and anti-D reference standards. International Council for Standardization in Haematology. International Society of Blood Transfusion.

Proteolytic enzyme preparations and techniques used routinely in blood group serology for the detection of atypical patient antibodies prior to transfusion vary widely and are often poorly standardised. Recent advances have been made in the use of biochemical methods to standardise and stabilise the potency of the enzyme preparations used. A joint working party of the International Council for Standardization in Haematology (ICSH) and the International Society of Blood Transfusion (ISBT) has investigated possibilities for the provision of standards for the protease preparations and techniques. The specification for these standards was that the performance of enzyme reference preparation in the reference technique should be of equivalent sensitivity to the ICSH/ISBT LISS spin indirect antiglobulin test using a titration series of a reference weak anti-D, and be free from false-positive reactions. The working party circulated materials for evaluation in inter-laboratory trials, followed by a laboratory workshop meeting to achieve agreement on the specification for reference materials and methods. Reference freeze-dried papain at 0.6 azoalbumin units and weak anti-D preparations (91/562) have been prepared and validated to meet these specifications. The performance of a test enzyme preparation in the technique for which it is recommended for use should be at least equal to that of the reference papain preparation, by the reference two-stage technique in terms of sensitivity, using a titration series of the reference anti-D, and freedom from false-positive reactions, using six fresh inert sera. The reference papain and weak anti-D can also be used to calibrate the level of proteolytic activity required in other procedures in blood group serology, such as new technology methods for antibody detection, and automated and microplate cell grouping procedures. These preparations and an agreed method for their use are now available from listed centres as ICSH/ISBT and Food and Drug Administration reference materials.

[Adjustment of the consensus guidelines on blood transfusion policies at hospitals]. / Bijstelling van de consensusrichtlijnen voor het bloedtransfusiebeleid in ziekenhuizen.

The consensus guidelines for blood transfusion in hospitals published in 1982 have been adjusted taking into account recent developments in compatibility testing, storage media for red cells, autologous blood transfusion and blood ordering. The 'type and screen'-strategy, previously recommended with certain restrictions, is now considered safe and advantageous as regards availability of blood for transfusion. The saline-adenine-glucose-mannitol (SAGM) solution for preservation of red cell concentrates is recommended as it has clinical and logistic advantages. Guidelines for pre- and peroperative autologous blood transfusion and the use of frozen autologous red cell concentrates are presented.

The pH optima for papain and bromelain treatment of red cells.

The action of papain and bromelain, prepared over a pH range from 4.6 to 8.6, was evaluated for the ability to render red cells agglutinable by five incomplete antibodies of differing blood group specificities using a two-stage technique. The optimal pH for treatment of red cells by activated papain or bromelain was between 5.4 and 5.8. Above this pH range, a fall in serological sensitivity was apparent which was much more pronounced with papain than with bromelain. The optimal pH for enzyme treatment of red cells can be achieved in two-stage techniques, but not in one-stage techniques due to the buffering effect of serum proteins.