A systematic review of the effect of red blood cell transfusion on mortality: evidence from large-scale observational studies published between 2006 and 2010

Abstract

ObjectiveTo carry out a systematic review of recently published large-scale observational studies assessing the effects of red blood cell transfusion (RBCT) on mortality, with particular emphasis on the statistical methods used to adjust for confounding. Given the limited number of randomised trials of the efficacy of RBCT, clinicians often use evidence from observational studies. However, confounding factors, for example, individuals receiving blood generally being sicker than those who do not, make their interpretation challenging.DesignSystematic review.Information sourcesWe searched MEDLINE and EMBASE for studies published from 1 January 2006 to 31 December 2010.Eligibility criteria for included studiesWe included prospective cohort, case–control studies or retrospective analyses of databases or disease registers where the effect of risk factors for mortality or survival was examined. Studies must have included more than 1000 participants receiving RBCT for any cause. We assessed the effects of RBCT versus no RBCT and different volumes and age of RBCT.Results–32 studies were included in the review; 23 assessed the effects of RBCT versus no RBCT; 5 assessed different volumes and 4 older versus newer RBCT. There was a considerable variability in the patient populations, study designs and level of statistical adjustment. Overall, most studies showed a higher rate of mortality when comparing patients who received RBCT with those who did not, even when these rates were adjusted for confounding; the majority of these increases were statistically significant. The same pattern was observed in studies where protection from bias was likely to be greater, such as prospective studies.ConclusionsRecent observational studies do show a consistently adverse effect of RBCT on mortality. Whether this is a true effect remains uncertain as it is possible that even the best conducted adjustments cannot completely eliminate the impact of confounding.

Causes of 30-day readmission after neurosurgery of the spine

“…10,13 The results from our review indicate that receiving blood transfusion is protective against unplanned readmission. 21 A potential explanation for this finding may be that although blood transfusion is often associated with higher rates of postoperative complications, morbidity, and mortality, 1,18,21,29 it may be an effective way of dealing with those complications before leaving the hospital. That is, a patient who undergoes a large vascular spinal fusion procedure may be appropriately treated with blood transfusion.…”

“…8,21,24 We found that postoperative complications were predictive in multiple studies, and others found that they were a common risk factor for 30-day readmission across multiple specialties. 8,18,21,24,25,27,30,32 Lovecchio et al 24 found that demographic factors, comorbid disease, and operative characteristics could not alone predict readmission rate, when complications remained as a covariate. Preoperative patient characteristics like diabetes, as shown above, increase the likelihood of complication, and these complications increase the risk of readmission.…”

Mortality, Morbidity and Related Outcomes Following Perioperative Blood Transfusion in Patients with Major Orthopaedic Surgery: A Systematic Review

“…Benefits and risks of red blood cell (RBC) concentrate transfusion have intensively and controversially been discussed in various publications [1,2,3,4]. The occurrence of well-known serious adverse reactions (transfusion-related infection, haemolysis, allergic reaction, transfusion-related acute lung injury (TRALI) etc.)…”

Transfusión según cifras de hemoglobina o de acuerdo con objetivos terapéuticos

“…Estos pacientes son difíciles de catalogar porque a menudo tienen una mayor comorbilidad, y puede ser difícil definir si los peores resultados son debidos a las condiciones preexistentes y las comorbilidades de los pacientes, o a la transfusión por sí misma, ofreciendo una condición de sesgo para los pacientes que son transfundidos 4 . Además, se añade el hecho de que en diferentes estudios, las transfusiones mejoran poco la condición clínica del paciente, lo que actualmente cuestiona su efectividad clínica 5,6 .…”