Guidelines summarize best evidence on red blood cell transfusion
Published in late 2009, guidelines on thresholds for red blood cell transfusion distill the best current evidence for common clinical situations faced in the ICU.
The guidelines, developed by a joint task force of the Eastern Association for Surgery of Trauma and the American College of Critical Care Medicine, divide recommendations on red blood cell (RBC) transfusion into seven categories: the general critically ill patient; sepsis; acute lung injury and acute respiratory distress syndrome; neurologic injury and diseases; transfusion risks; alternatives to transfusion; and strategies to reduce transfusion.
The guidelines depend heavily on the 10-year-old Transfusion Requirements in Critical Care Trial, which found that a restrictive transfusion strategy was at least as effective as a liberal one, an accompanying editorial said.
The recommendations also question current guidelines on sepsis that recommend transfusing packed red cells if necessary to hematocrit of >30%, citing multiple studies that failed to find benefit from transfusion in septic patients, the editorial noted.
Of importance, the guidelines point out that the evidence is insufficient to support a more liberal transfusion strategy in areas of continued controversy, such as sepsis, acute lung injury, acute respiratory distress syndrome, acute coronary syndromes and neurologic injury.
The guidelines provide the clearest direction to date, the editorial said, until there are more data on the short- and long-term risks and benefits of transfusion.
Some of the task force's recommendations include:
- For the general critically ill patient, transfusion is indicated for patients with evidence of hemorrhagic shock and may be indicated for patients with acute hemorrhage and hemodynamic instability or inadequate oxygen delivery. (Level 1 evidence)
- In general critically ill patients, a restrictive strategy of transfusion (Hb <7 g/dL) is as effective as a liberal strategy (Hb <10 g/dL) in patients with hemodynamically stable anemia, except possibly those with acute myocardial ischemia. (Level 1 evidence)
- Transfusion needs for sepsis patients must be assessed individually because optimal transfusion triggers are not known and there is no clear evidence that blood transfusion increases tissue oxygenation. (Level 2 evidence)
- All efforts should be made to avoid transfusion in patients at risk for acute lung injury and acute respiratory distress syndrome after resuscitation. (Level 2 evidence)
- There is no benefit of a liberal transfusion strategy in patients with moderate-to-severe traumatic brain injury. (Level 2 evidence)
- Transfusion is associated with increased nosocomial infection. (Level 2 evidence)
The complete guidelines were published in the December 2009 Critical Care Medicine.
Hospitals keep door-to-balloon time below 90 minutes for more patients
Following the launch of a national program to reduce door-to-balloon times for heart attack patients, hospitals increased to 76% those eligible patients who received angioplasty within 90 minutes of hospital arrival, with rates rising by more than 10% annually for several years, a study found.
The Door-to-Balloon (D2B) Alliance, a group of 39 organizations, launched the program in November 2006 to help hospitals lower D2B times for ST-segment elevation myocardial infarction (STEMI) patients to within 90 minutes.
Study authors evaluated D2B times at 831 hospitals between April 1, 2005, and March 31, 2008, to examine changes in D2B times before and after the program was implemented, and differences in times for patients treated at hospitals participating in the program versus patients at non-participating hospitals.
Program strategies included having a single call activate the cath lab and having the cath lab team arrive within 30 minutes of the call.
By March 2008, 76% of STEMI patients received PCI within 90 minutes, compared to 62.8% in 2006 before the program was launched, and 52.5% in 2005. Patients treated in hospitals enrolled in the D2B Alliance program for more than three months were significantly more likely than those in non- participating hospitals to have D2B times within 90 minutes (P=0.001; odds ratio: 1.16; 95% CI, 1.07 to 1.27), although the magnitude of the reported difference was modest. Reported use of each strategy recommended by the Alliance increased significantly (P<0.001) from enrollment to follow-up in participating hospitals. Cumulatively, over the 17 total months after the start of the D2B Alliance, 75% of patients in participating hospitals had D2B times within 90 minutes, compared to 69% of non-participating hospitals.
It's difficult to determine the precise role the D2B Alliance campaign played in reducing D2B times, the authors said. The program enrolled more than 70% of hospitals that perform PCI, and its educational materials—such as webinars and newsletters—were publicly accessible.
“Spillover and herd effects, which could result in widespread improvement beyond those officially enrolled, are likely,” the authors noted. As well, guideline revisions and publication of research evidence may have played a role in D2B times, they said.
Regardless of the cause, the improved timeliness of care is an impressive achievement, the authors concluded.
Results were published in the December 15/22, 2009 Journal of the American College of Cardiology.