Optimal preoperative autologous blood storage volume required in surgeries for placenta previas and low-lying placentas.

AIM: The high rate of stored preoperative autologous blood wastage is concerning. This study analyzed patients who provided preoperative autologous blood donations (PABDs) for massive bleeding during surgery for placenta previas and low-lying placentas, and investigated the optimal PABD storage volume required to avoid allogeneic transfusion. METHODS: Of 386 patients who provided PABDs at our hospital from 2008 to 2013, 269 patients with placenta previas or low-lying placentas were retrospectively analyzed. The PABD storage volumes were stratified into four groups based on the amounts stored, and the allogeneic transfusion usage frequencies were compared. RESULTS: A total of 124 patients (46.1%) received PABDs and 12 patients (4.5%) received allogeneic transfusions. The average PABD volume wasted was 23 940 mL/year. The allogeneic transfusion utilization rate was significantly higher in the 1- to 300-mL group (17.2%) than in the 301- to 600-mL (1.69%), 601- to 900-mL (3.82%), and 901- to 1200-mL (0%) groups (P < 0.05). The PABD cut-off volume for avoiding allogeneic blood transfusion was 300 mL, and the odds ratio for ≤300-mL PABD in a multivariate analysis was 14.3 (95% confidence interval 1.3-149.3; P = 0.03). The maximum surgical blood order schedule was 2.16 units (432 mL), and the surgical blood order equation was 2.15 units (430 mL). CONCLUSION: The allogeneic transfusion utilization rate did not differ between the 600-mL group and the groups with higher PABD storage volumes; hence, storing 600 mL of PABD was appropriate for surgery for placenta previas and low-lying placentas.

Prediction of the effect of acute normovolemic hemodilution on the hematological constituents of sequestered autologous whole blood.

During acute normovolemic hemodilution (ANH), autologous whole blood is collected in a series of collection bags containing anticoagulant. The effect of hemodilution on the actual hematological constituents of this sequestered whole blood product has never been examined. We developed a mathematical model that predicts how whole blood bag constituents change during ANH to elucidate the theoretical basis for ANH efficacy. Formulas were derived to calculate the effect of ANH on [X], the blood constituent of interest. An exponential envelope was defined so that the projected impact of ANH on each constituent could be computed while initial blood volume and whole blood bag volume (WB(ANH)) were manipulated. Equivalency of autologous whole blood hemoglobin, platelets, and fibrinogen were determined by comparison with standard allogeneic blood products. We determined that the concentration of blood constituent X in a particular unit of collected blood ([X](n)) is provided as a fraction of the initial concentration ([X](0)). As WB(ANH) increases relative to estimated blood volume, the decrement in [X](n) increases in successive blood collection bags. Irrespective of initial blood volume, the equivalence of a 450-mL autologous whole blood bag to 1 U of packed red cells and 1 U of whole blood-derived platelet concentrate is 13.3 g/dL and 123 x 10(3)/microL, respectively. The impact of ANH on autologous whole blood constituents may be accurately predicted using this model. Conversion of WB(ANH) into equivalent allogeneic blood products could provide a useful method of comparing outcome in various ANH studies. The exponential envelope may be used to assess the actual ANH technique performed by the anesthesiologist, which in turn may impact quality assurance standards.

[Prospective study of the causes for destruction of labile blood products during 1999 at a University Hospital Center]. / Etude prospective des causes de destruction des produits sanguins labiles, au cours de l'année 1999 dans un CHU.

The destruction of the blood cell product (BCP) is a situation which is hard to accept in the present context of transfusional safety which aims at covering the transfusional needs in the most appropriate way. In our University Hospital, 500 BCP out of 20,000 are destroyed per year, which represent a cost of 100,000 $. A prospective research was carried out from January 1st to December 31st 1999 in order to analyse the causes of the destruction of the BCP and to differentiate the inevitable destructions for the patient's security from the avoidable destructions which might have benefited from corrective measures. For each group of simultaneously destroyed BCP, an information note specified the patient's pathology, the reasons for the prescription, the number and the type of transfused and destroyed BCP in the same day, the time spent between distribution and return, and the causes of destruction. In 1999, a total of 483 LBP out of 19,802 which were distributed, have been returned and destroyed, that is to say 2.4% for a 99.3% traceability which involved 242 patients. Among these destroyed BCP, 28.3% came from inevitable causes--death or acute intensive care which needed a lot of transfusions--69.7% were categorised as being related to avoidable causes depending on the organisation of transport and care, unadapted safety measures. The corrective measures to be taken, concern the improvement of transport procedures, the set-up of a nominative BCP reservation system in the Blood Center, the scheduling of the BCP deliveries from the blood bank, and a better adaptation of the safety measures to the transfusional needs.

[The organization of the donation of autologous blood and its components in cardiac surgery]. / Organizatsiia autodonorstva krovi i ee komponentov v kardiokhirurgii.

The article analyzes an experience with the organization of autodonation of blood and its components in surgical treatment of 305 patients with congenital and acquired defects and ischemic heart disease. Methods of plasmacytapheresis and cryopreservation used at the terms from 3 days to 12 months before operation allowed storage of the autologous components of blood in 41.2% of the patients having indications for autodonation. In 29.1% of the observations the autotransfusion media were reserved under the outpatient clinic conditions which resulted in shorter terms of treatment at the hospital. The number of unfavorable reactions during the donation in patients did not exceed analogous parameters in regular donors. Autohemotransfusions 3-5 times reduced the volume of transfusions of the allogenic blood components and they were completely avoided in 20.1% of the patients.