Cell salvage and donor blood transfusion during cesarean section: A pragmatic, multicentre randomised controlled trial (SALVO)

• Published in: PLoS medicine Vol. 14; no. 12; p. e1002471
• Main Authors: Khan, Khalid S, Moore, Philip A S, Wilson, Matthew J, Hooper, Richard, Allard, Shubha, Wrench, Ian, Beresford, Lee, Roberts, Tracy E, McLoughlin, Carol, Geoghegan, James, Daniels, Jane P, Catling, Sue, Clark, Vicki A, Ayuk, Paul, Robson, Stephen, Gao-Smith, Fang, Hogg, Matthew, Lanz, Doris, Dodds, Julie
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 19.12.2017; Public Library of Science (PLoS)
• Subjects: Adult; Amniotic fluid; Analysis; Biology and Life Sciences; Blood; Blood Donors; Blood Loss, Surgical - prevention & control; Blood transfusion; Blood Transfusion, Autologous - methods; Blood transfusions; Cesarean section; Cesarean Section - adverse effects; Cesarean Section - methods; Clinical trials; Dentistry; Embolism; Female; Funding; Gynecology; Health economics; Hematology; Hemorrhage; Hospitals; Humans; Intervention; Medical research; Medicine; Medicine and Health Sciences; Methods; Motivation; Obstetrics; Operative Blood Salvage - methods; Patient Care Planning; Patient outcomes; Physiological aspects; Pregnancy; Primary care; Prognosis; Public health; Randomization; Salvage; Social Sciences; Statistical analysis; Supervision; Transfusion; Treatment Outcome
• ISSN: 1549-1676; 1549-1277; 1549-1676
• DOI: 10.1371/journal.pmed.1002471

Excessive haemorrhage at cesarean section requires donor (allogeneic) blood transfusion. Cell salvage may reduce this requirement. We conducted a pragmatic randomised controlled trial (at 26 obstetric units; participants recruited from 4 June 2013 to 17 April 2016) of routine cell salvage use (intervention) versus current standard of care without routine salvage use (control) in cesarean section among women at risk of haemorrhage. Randomisation was stratified, using random permuted blocks of variable sizes. In an intention-to-treat analysis, we used multivariable models, adjusting for stratification variables and prognostic factors identified a priori, to compare rates of donor blood transfusion (primary outcome) and fetomaternal haemorrhage ≥2 ml in RhD-negative women with RhD-positive babies (a secondary outcome) between groups. Among 3,028 women randomised (2,990 analysed), 95.6% of 1,498 assigned to intervention had cell salvage deployed (50.8% had salvaged blood returned; mean 259.9 ml) versus 3.9% of 1,492 assigned to control. Donor blood transfusion rate was 3.5% in the control group versus 2.5% in the intervention group (adjusted odds ratio [OR] 0.65, 95% confidence interval [CI] 0.42 to 1.01, p = 0.056; adjusted risk difference -1.03, 95% CI -2.13 to 0.06). In a planned subgroup analysis, the transfusion rate was 4.6% in women assigned to control versus 3.0% in the intervention group among emergency cesareans (adjusted OR 0.58, 95% CI 0.34 to 0.99), whereas it was 2.2% versus 1.8% among elective cesareans (adjusted OR 0.83, 95% CI 0.38 to 1.83) (interaction p = 0.46). No case of amniotic fluid embolism was observed. The rate of fetomaternal haemorrhage was higher with the intervention (10.5% in the control group versus 25.6% in the intervention group, adjusted OR 5.63, 95% CI 1.43 to 22.14, p = 0.013). We are unable to comment on long-term antibody sensitisation effects. The overall reduction observed in donor blood transfusion associated with the routine use of cell salvage during cesarean section was not statistically significant. This trial was prospectively registered on ISRCTN as trial number 66118656 and can be viewed on http://www.isrctn.com/ISRCTN66118656.