Objective:To determine the effect of blood component ratios in massive transfusion (MT), we hypothesized that increased use of plasma and platelet to red blood cell (RBC) ratios would result in decreased early hemorrhagic death and this benefit would be sustained over the ensuing hospitalization.Sum

Increased plasma and platelet to red blood cell ratios improves outcome in 466 massively transfused civilian trauma patients

In 1994, the American Society of Anesthesiologists established the Task Force on Blood Component Therapy to develop evidence‐based indications for transfusing red blood cells, platelets, fresh‐frozen plasma, and cryoprecipitate in perioperative and peripartum settings. The guidelines were developed according to an explicit methodology. The principal conclusions of the task force are that red blood cell transfusions should not be dictated by a single hemoglobin \"trigger\" but instead should be based on the patient's risks of developing complications of inadequate oxygenation. Red blood cell transfusion is rarely indicated when the hemoglobin concentration is greater than 10 g/dL and is almost always indicated when it is less than 6 g/dL. The indications for autologous transfusion may be more liberal than for allogeneic (homologous) transfusion. The risks of bleeding in surgical and obstetric patients are determined by the extent and type of surgery, the ability to control bleeding, the actual and anticipated rate of bleeding, and the consequences of uncontrolled bleeding. Prophylactic platelet transfusion is ineffective when thrombocytopenia is due to increased platelet destruction. Surgical and obstetric patients with microvascular bleeding usually require platelet transfusion if the platelet count is less than 50 x 109 /l and rarely require therapy if it is greater than 100 x 10 sup 9 /l. Fresh‐frozen plasma is indicated for urgent reversal of warfarin therapy, correction of known coagulation factor deficiencies for which specific concentrates are unavailable, and correction of microvascular bleeding when prothrombin and partial thromboplastin times are > 1.5 times normal. It is contraindicated for augmentation of plasma volume or albumin concentration. Cryoprecipitate should be considered for patients with von Willebrand's disease unresponsive to desmopressin, bleeding patients with von Willebrand's disease, and bleeding patients with fibrinogen levels below 80–100 mg/dL. The task force recommends careful adherence to proper indications for blood component therapy to reduce the risks of transfusion.

Practice guidelines for blood component therapy: A report by the American Society of Anesthesiologists Task Force on Blood Component Therapy

Mechanism of abnormal bleeding in patients undergoing cardiopulmonary bypass: acquired transient platelet dysfunction associated with selective alpha-granule release.

Background. Recalcitrant coagulopathy the bloody vicious cycle, produces the majority of deaths after torso trauma. A model predicting this life-threatening complication may facilitate clinical decision-making. Methods. We prospectively analyzed patients > 15 years old who received a massive transfusion (> 10 units of packed red blood cells (PRBC)/24 h) over a 2-year period. Excluding massive head injuries and pre-existing disease, the 58 study patients had a mean age = 35.4 years, Injury Severity Score (ISS) = 30.6, and PRBC = 24.2 units/24 h. Results. Defined as prothrombin time of two times that of normal laboratory controls and partial thromboplastin time as two times that of normal laboratory controls, 27 patients (47%) developed life-threatening coagulopathy. Using a multiple logistic regression model, the four significant risk factors (with odds ratio) were (1) pH 25 (7.7), and (4) systolic blood pressure 25 + systolic blood pressure 25 + temperature 25 + pH < 7.10 = 49%; with all four risk factors the incidence was 98%. Conclusion. Postinjury life-threatening coagulopathy in the seriously injured requiring massive transfusion is predicted by persistent hypothermia and progressive metabolic acidosis.

Predicting life-threatening coagulopathy in the massively transfused trauma patient: hypothermia and acidoses revisited.

The purpose of this study was to assess the change of platelet and fibrinogen concentrations and the change of activities of prothrombin and factors V and VII when major surgical blood loss was replaced with plasma-poor red cell concentrates (RCCs) and colloid plasma substitutes. Sixty patients were studied. The average blood loss was 65% +/- 41% of the calculated blood volume (CBV). Blood loss was monitored carefully and replaced without delay to ensure stable blood volume. Blood samples were obtained at the induction of anesthesia and at the end of the recovery room period, or before the patient was given fresh frozen plasma. In addition, a platelet count was determined after each 20% blood loss. The results were converted to relative values, and simple linear regression with logarithmic transformation was applied. The initial platelet concentration was 257 +/- 89 x 10(3)/mm3 and the extrapolation of the regression line intercepted the critical level of 50 x 10(3)/mm3 at 230% (confidence interval 169%-294%) blood loss. The initial fibrinogen concentration was 3.7 +/- 1.1 g/L and the hemostatically significant level of 1.0 g/L was already reached at 142% (117%-169%) blood loss (r2 = 0.90). Activities of prothrombin and coagulation factors V and VII reached their critical levels at 201% (160%-244%), 229% (167%-300%), and 236% (198%-277%) blood loss, respectively. We conclude that deficiency of fibrinogen develops earlier than any other hemostatic abnormality when plasma-poor RCCs are used for the replacement of major blood loss.

Hemostatic factors and replacement of major blood loss with plasma-poor red cell concentrates.

Coagulation defects associated with massive blood transfusions.

Coagulation defects associated with massive blood transfusions

No correlation was observed between the amount of stored acid-citrate-dextrose blood administered and magnitude of negative base excess measured in 20 patients, some in shock and some not. Extreme variability in acid-base response to multiple blood transfusion would appear to make routine bicarbonate administration unadvisable. Four of five patients receiving greater than 100 mEq of sodium bicarbonate intraoperatively had postoperative arterial pH of greater than 7.48. Only two of 11 patients who received less than 100 mEq of sodium bicarbonate intraoperatively had postoperative arterial pH values greater than 7.48. Because of an undesirable shift of the oxygen dissociation curve to the left with an alkaline pH, it is suggested that bicarbonate therapy should be reserved for patients with severe metabolic acidosis (base excess, —7 mEq/liter or more) which can be established only by analysis of arterial blood for arterial carbon dioxide tension and pH.

https://jamanetwork.com/journals/jama/articlepdf/337900/jama_216_11_008.pdf

Thomas O. Robbins

Papers

Coagulation defects associated with massive blood transfusions.

Coagulation defects associated with massive blood transfusions

Effects of massive transfusion of blood on acid-base balance.

Blood coagulation studies in Plasmodium falciparum malaria.