Classifying Transfusions Related to the Anemia of Critical Illness in Burn Patients

Abstract

Background Critically ill patients require transfusions because of acute blood loss and the anemia of critical illness. In critically ill burn patients, typically, no distinction is made between transfusions related to acute surgical blood loss and those related to the anemia of critical illness. We sought to identify the percentage of blood transfusions due to the anemia of critical illness and the clinical characteristics associated with these transfusions in severely burned patients. Methods Sixty adult patients with ≥20% total body surface area (TBSA) burn who were transfused at least 1 unit of packed red blood cells during their hospitalization were studied. Clinical variables including age, %TBSA burn, Acute Physiology and Chronic Health Evaluation (APACHE) II score, number of ventilator days, inhalation injury, and number of operative events were correlated with the total number of packed red blood cell units and percentage of nonsurgical transfusions in these patients. Nonsurgical transfusions were defined as transfusions occurring after postoperative day 1 for each distinct operative event and were classified as being caused by the anemia of critical illness. Results Patients were transfused an average of 16.6 units ± 21.2 units. Nonsurgical transfusions accounted for 52% of these transfusions. APACHE II score, %TBSA burn, number of ventilator days, and number of operative events, all correlated with total transfusions. However, nonsurgical transfusions correlated with only APACHE II score (p = 0.01) and number of ventilator days (p = 0.03). There was no correlation between nonsurgical transfusions and other clinical variables. Conclusion The anemia of critical illness is responsible for >50% of all transfusions in severely burned patients. The initial severity of critical illness (APACHE II score) and duration of the critical illness (number of ventilator days) correlated with transfusions related to anemia of critical illness. Further investigation into the specific risk factors for these transfusions may help to develop strategies to further reduce transfusion rates.

Predicting postoperative haemoglobin changes after burn surgery

“…The anaemia of critical illness in burn patients describes a continuous slow decrease in Hb in the first days after surgery. [9] It is therefore possible that the postoperative Hb nadir may only be reached a few days after burn surgery for patients not transfused in the postoperative period. Good clinical judgement, taking into consideration the risk associated with unnecessary blood transfusion compared with that of undertransfusion, is required with these patients.…”

Discrete β-adrenergic mechanisms regulate early and late erythropoiesis in erythropoietin-resistant anemia

“…About 12 million units of packed RBCs are utilized per year in the United States alone. Among severely burned patients, more than half of all transfusions is attributed to anemia of critical illness; correlating with the initial severity and duration of critical illness based on APACHE II score and number of ventilator days respectively (5). Even though anemia of thermal burns was first noticed in 1946 (6), to this date there is no other alternative to transfusion (7).…”

Evaluating the appropriateness of blood component utilization in burns patients

“…30 But other studies by Posluzny et al (16.6 units), Palmieri et al (13.7 units) and Gupta et al (8 units) showed a higher mean number of blood units transfused. 7,12,31 Most of the red cells transfused in burn patients in this present study belonged to second and third week of storage, which was similar to mean storage age of 16.2 days in the study by Vincent et al and 16-21 days by Aubron et al 30,32 The patient profiles in the present study had varied, from a patient who was conservatively managed without any blood component transfusion to an electrical burns patient, who was transfused with 25 units of red cells, 7 units of fresh frozen plasma and 1 unit of platelets and underwent 4 surgical procedures. Use of blood components when are they are not necessary, for example patients with minor or partial thickness burns, who can be managed with fluids only, constitutes inappropriateness.…”

“…13 Despite modifications to transfusion thresholds over the past 20 years, transfusion thresholds still differ between various burn centers. 7 In patients without cardiac compromise, blood transfusion can be withheld to hemoglobin levels as low as 7.0 to 8.0 gm/dL as long as there is no active bleeding. 13 Blood transfusions are necessary in burn patients losing more than 700 ml at any one time or have a fall in Hemoglobin to 8 gm%.…”

“…Conditions that necessitate transfusions related to anemia in burn patients are not well defined. 7 This study was undertaken to find out the appropriateness of blood usage pattern in Burns patients which will help the Burns treatment team to utilize the invaluable resource appropriately, predict future blood demand and help maintain transfusion inventory for specialized burn units.…”