It is difficult to avoid the use of red blood cell transfusion (RBCT) in patients with chronic kidney disease (CKD) due to the complex pathophysiology of anemia in this population and the limitations of current anemia therapies, according to the authors of a new review published in the Journal of Nephrology.
Nonetheless, RBCT rates in the CKD population have been declining in the last decade, Anirban Ganguli, MD, of Georgetown University in Washington, DC, and colleagues reported. According to the USRDS-2018 datasheet, the percentage of HD patients receiving more than 1 RBCT declined from 23.9% in 2012 to 16.6% in 2016, they stated.
In a “Discrete Choice Experiment” survey, prescribers cited absolute hemoglobin (Hb) level (29%), patient’s functional status (16%), and cardiovascular comorbidities (12%) as the top reasons for RBCT. Transplant eligibility explained only 5% of decision-making process.
Underuse of erythropoiesis-stimulating agents (ESA) and ESA hyporesponsiveness are important reasons for RBCT, according to the reviewers. In a 2015 BMC Nephrology study of hemodialysis patients, ESA hyporesponsiveness occurred in 12.5% of patients with a majority regaining ESA responsiveness within 4 months. Young black female patients using a central venous catheter for dialysis access were particularly prone to ESA hyporesponsiveness, as were patients with greater co-morbidity burden, coexisting non-renal causes of anemia, or recent antibiotic therapy. The frequency of monthly RBCT was 5-fold and 7-fold higher in acute and chronic (more than 4 months) ESA hyporesponsive patients, respectively, and such patients had a significantly higher risk of mortality than ESA responders.
Transfusion policies tend to fall into either a liberal or restrictive (Hb less than 7, 8, or 9 g/dL) camp, the reviewers noted. Due to the paucity of randomized studies, they believe theKidney Disease Improving Global Outcomes (KDIGO) 2012 anemia guidelines and the American Association of Blood Banks (AABB) 2016 guidelines provide valuable general recommendations on transfusion.
According to the AABB guidelines, Hb level and symptoms should guide RBCT. Hemodynamically stable inpatients and patients in the intensive care unit can be transfused when Hb falls to 7 g/dL or less. Postoperative orthopedic or cardiac surgery patients and those with cardiovascular disease can be transfused when Hb drops to 8 g/dL or less or when patients experience symptoms.
KDIGO guidelines recommend avoiding RBCT when possible to minimize risks such as blood-borne infections, iron overload, circulatory overload, or allosensitization. Patients with CKD who experience allosensitization to foreign antigens tend to have longer kidney transplant wait times and graft loss, so KDIGO recommends avoiding RBCT in those eligible for kidney transplantation. The decision to transfuse a patient with CKD with non-acute anemia should be based on symptoms rather than Hb thresholds, according to KDIGO. RBCT benefits may outweigh risks in patients who do not respond well to ESA therapy, including those with ESA resistance.
In addition to these guidelines, Dr Ganguli and his coauthors suggested the following strategies to optimize transfusion without compromising patient safety:
1. Whenever possible, continue to use ESA with or without intravenous iron in patients with CKD when they are acutely ill and admitted in hospital unless there are contraindications to using these agents.
2. Use less invasive procedures with hospitalized patients with CKD.
3. In every CKD patient, triage the decision for blood-transfusion based on whether the patient is a future candidate for renal transplantation.
4. Individualize transfusion need based on acuity of situation; for example, when the threshold of transfusion in acute blood loss may be higher than chronic asymptomatic anemia.
5. Patients with anemia in the setting of acute cardiovascular conditions such as acute myocardial infarction or postcardiac surgery may need a higher than usual transfusion threshold.
Brenner N, Kommalapati A, Ahsan M, Ganguli A. Red cell transfusion in chronic kidney disease in the United States in the current era of erythropoiesis stimulating agents. J Nephrol. doi:10.1007/s40620-019-00680-5