Transfusion
A blood transfusion threshold of no higher than 8g/dl is suggested in asymptomatic postoperative hip fracture patients.

Rationale

Several moderate strength studies (Carson 2015, Carson 2011, Gregersen 2015, Gruber-Baldini, 2013, Parker 2013) support this recommendation. Carson (2011) FOCUS trial is the largest (n=2016) and most robust study to address transfusion threshold in hip fracture patients. FOCUS considered patient-centered and clinically important outcomes in a prospective, randomized, multicenter, controlled trial. This study showed that a restrictive transfusion threshold of hemoglobin 8g/dl in asymptomatic hip fracture patients with cardiovascular disease or risk factors resulted in no significant difference in primary or secondary outcomes at 30- or 60-days including mortality, independent walking ability, residence, other functional outcomes, cardiovascular events, or length of stay. Symptoms or signs that were considered indicative of anemia appropriate for transfusion were chest pain that was deemed to be cardiac in origin, congestive heart failure, and unexplained tachycardia or hypotension unresponsive to fluid replacement. Gregersen’s (2015) study comparing 9.7g/dl vs. 11.3 g/dl also showed no significant difference in most of the primary or secondary outcomes. 

Of note, in the Carson (2011) study, for patients in the restrictive-strategy group (8g/dl) and for patients in both groups in the Gregerson (2015) study, blood was transfused 1 unit at a time and the patient reassessed for presence of symptoms or signs after each transfusion.  

Benefits/Harms of Implementation

Implementation of this recommendation is likely to result in lower transfusion associated complications and cost. There is risk that cognitively impaired patients cannot report symptoms, so special attention to these individuals may be warranted; FOCUS automatically transfused significantly demented patients below hemoglobin 8mg/dl. 

Future Research

Confirmatory studies by other authors would strengthen evidence. Additional studies could further risk stratify and refine transfusion thresholds in subpopulations.