Acute lung damage related to blood transfusions continues to affect about one in every 100 surgery patients, despite efforts to reduce the incidence of the life-threatening condition.
Anesthesiologists at Mayo Clinic found that the rate of transfusion-related acute lung injury (TRALI) decreased between 2004 and 2011 against a backdrop of various novel mitigation strategies. Another study, in Canada, concluded that almost 40% of reported TRALI cases in that country occurred during the perioperative period.
“TRALI is the leading cause of transfusion-related fatalities in the United States,” said Leanne Clifford, BM, MSc, an anesthesia resident at Mayo Clinic, in Rochester, Minn. “We know that approximately 50% of blood products are given in the operating room, and a recent study has suggested that 40% of TRALI episodes occur in the perioperative setting. Despite these facts, nobody has to date specifically studied the patient characteristics and risk factors for TRALI in a surgical population.”
To shed light on this area, Dr. Clifford and her colleagues evaluated the records of all patients older than age 18 years undergoing noncardiac surgery and who received transfusions during the procedure (N=3,380).
The researchers identified cases by screening patient medical records using a highly sensitive electronic algorithm for the detection of TRALI or possible TRALI (sensitivity, 92.5%; specificity, 93.6%). Two independent physicians then reviewed each positive record. “Where discrepancies arose, a panel of three senior critical care physicians adjudicated the final outcome,” Dr. Clifford said.
The cumulative incidence of TRALI and possible TRALI, in 2004 and 2011, was 1.3%. “We found a significantly higher rate of TRALI compared to what has been previously described in the literature,” Dr. Clifford noted.
“Interestingly, we did not actually observe a significant decline in the rate of TRALI between 2004 and 2011, before and after the introduction of various mitigation strategies which have been previously well demonstrated to reduce TRALI,” she added.
The rate of TRALI varied with the type of surgery, according to the researchers, who first reported their findings at the 2013 annual meeting of the American Society of Anesthesiologists (abstract 2228). Thoracic (3%), vascular (2.7%) and transplant (2.2%) surgeries carried the highest rates of TRALI, while obstetric and gynecologic surgical patients had no TRALI episodes during either study year. The rate of TRALI or possible TRALI increased with age (P=0.041) and volume of blood transfused (P<0.001; Table). The incidence of the condition was comparable in men and women (1.3% vs. 1.1% in 2004; 1.5% vs. 1.4% in 2011; P=0.764).
Table. Characteristics of TRALI Cases
2004 2011 Overall
Age, y N n (%) N n (%) N n (%)
≤49 318 3 (0.9) 277 3 (1.1) 595 6 (1.0)
50-59 296 1 (0.3) 288 3 (1.0) 584 4 (0.7)
60-69 415 4 (1.0) 421 6 (1.4) 836 10 (1.2)
70-79 486 8 (1.6) 370 5 (1.4) 856 13 (1.5)
80+ 303 6 (2.0) 206 5 (2.4) 509 11 (2.2)
Transfusion volume, mL
≤350 606 2 (0.3) 512 4 (0.8) 1118 6 (0.5)
351-700 635 2 (0.3) 485 5 (1.0) 1120 7 (0.6)
701-1,050 201 3 (1.5) 187 2 (1.1) 388 5 (1.3)
1,051-1,400 130 2 (1.5) 101 2 (2.0) 231 4 (1.7)
≥1,401 246 13 (5.3) 277 9 (3.2) 523 22 (4.2)
“The increase in incidence with increased transfusion volume is a phenomenon that has been previously described, essentially a dose-related phenomenon,” Dr. Clifford said. “The more blood products you receive, the more likely you are to receive a product that will precipitate a TRALI reaction.”
A University of Toronto research team also investigated the rate of perioperative TRALI, based on data from the Canadian Blood Services (abstract A2226). The investigators reviewed all suspected TRALI cases reported to the organization between 2001 and 2012. A second arm categorized suspected cases as occurring within 72 hours of surgery (perioperative) or outside of that period (non-perioperative).
The study found that between 2001 and 2012, 303 suspected cases of TRALI were reported to Canadian Blood Services. Of those, 112 (38%) were identified as occurring during the perioperative period. Cardiac surgery requiring cardiopulmonary bypass (25%), general surgery (18%) and orthopedic procedures (12.5%) represented the three largest surgical groups.
Patients developing TRALI perioperatively were, on average, transfused more products than non-perioperative patients. Perioperative TRALI patients were also transfused more frozen and fresh frozen plasma and cryoprecipitate than non-TRALI patients.
Perioperative TRALI cases were also found to consist of more men (53.6 vs. 41.4; P=0.0395) than non-perioperative TRALI patients. Furthermore, a greater proportion of perioperative TRALI patients required supplemental oxygen (14.3% vs. 3.1%; P=0.0003), required mechanical ventilation (18.8% vs. 3.1%) or were from the ICU (14.3% vs. 3.7%; P=0.0043), than non-perioperative patients before their operations.
“Perioperative TRALI is probably something that we need to be more aware of,” Dr. Clifford concluded. “If we can identify TRALI cases in real time, then we may be able to find and investigate the donors, and potentially consider whether they need to be excluded from the donor pool to prevent them precipitating further TRALI reactions in future patients.
“It will also enable us to conduct better studies into TRALI’s potential mechanisms, and therefore treat patients in a more timely and appropriate manner.”