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.
Caesarean section is associated with blood loss and maternal morbidity. Excessive blood loss requires transfusion of donor (allogeneic) blood, which is a finite resource. Cell salvage returns blood ...lost during surgery to the mother. It may avoid the need for donor blood transfusion, but reliable evidence of its effects is lacking.
To determine if routine use of cell salvage during caesarean section in mothers at risk of haemorrhage reduces the rates of blood transfusion and postpartum maternal morbidity, and is cost-effective, in comparison with standard practice without routine salvage use.
Individually randomised controlled, multicentre trial with cost-effectiveness analysis. Treatment was not blinded.
A total of 26 UK obstetric units.
Out of 3054 women recruited between June 2013 and April 2016, we randomly assigned 3028 women at risk of haemorrhage to cell salvage or routine care. Randomisation was stratified using random permuted blocks of variable sizes. Of these, 1672 had emergency and 1356 had elective caesareans. We excluded women for whom cell salvage or donor blood transfusion was contraindicated.
Cell salvage (intervention) versus routine care without salvage (control). In the intervention group, salvage was set up in 95.6% of the women and, of these, 50.8% had salvaged blood returned. In the control group, 3.9% had salvage deployed.
Primary - donor blood transfusion. Secondary - units of donor blood transfused, time to mobilisation, length of hospitalisation, mean fall in haemoglobin, fetomaternal haemorrhage (FMH) measured by Kleihauer-Betke test, and maternal fatigue. Analyses were adjusted for stratification factors and other factors that were believed to be prognostic a priori. Cost-effectiveness outcomes - costs of resources and service provision taking the UK NHS perspective.
We analysed 1498 and 1492 participants in the intervention and control groups, respectively. Overall, the transfusion rate was 2.5% in the intervention group and 3.5% in the control group adjusted odds ratio (OR) 0.65, 95% confidence interval (CI) 0.42 to 1.01;
= 0.056. In a planned subgroup analysis, the transfusion rate was 3.0% in the intervention group and 4.6% in the control group among emergency caesareans (adjusted OR 0.58, 95% CI 0.34 to 0.99), whereas it was 1.8% in the intervention group and 2.2% in the control group among elective caesareans (adjusted OR 0.83, 95% CI 0.38 to 1.83) (interaction
= 0.46, suggesting that the difference in effect between subgroups was not statistically significant). Secondary outcomes did not differ between groups, except for FMH, which was higher under salvage in rhesus D (RhD)-negative women with RhD-positive babies (25.6% vs. 10.5%, adjusted OR 5.63, 95% CI 1.43 to 22.14;
= 0.013). No case of amniotic fluid embolism was observed. The additional cost of routine cell salvage during caesarean was estimated, on average, at £8110 per donor blood transfusion avoided.
The modest evidence for an effect of routine use of cell salvage during caesarean section on rates of donor blood transfusion was associated with increased FMH, which emphasises the need for adherence to guidance on anti-D prophylaxis. We are unable to comment on long-term antibody sensitisation effects. Based on the findings of this trial, cell salvage is unlikely to be considered cost-effective.
Research into risk of alloimmunisation among women exposed to cell salvage is needed.
Current Controlled Trials ISRCTN66118656.
This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in
; Vol. 22, No. 2. See the NIHR Journals Library website for further project information.
This study aimed to evaluate the effectiveness of inpatient care models during induction of labour (IOL). A prospective observational study involving 1,133 women undergoing IOL in a tertiary ...obstetric centre was conducted between March 2009 and August 2010. Three models of care were evaluated: model A – women were admitted when workload permitted, and cared for by midwives who may also be caring for women in labour. Model B – women were given specific appointments and cared for by dedicated IOL midwives working a total of 40 hours or (model C) 84 hours per week. Model C resulted in a reduction in admission-to-birth interval when compared to models A and B (p <0.0001). Compared to model A, the relative risk of caesarean birth (CS) for model C was 0.71 (0.52 – 0.97, p = 0.034). A dedicated IOL midwife may be associated with shorter admission-to-birth intervals and lower CS rates.
Academic Unit of Child Health, University of Manchester and
Department of Obstetrics and Gynecology, St. Mary's Hospital,
Manchester M13 0JH, United Kingdom
We have investigated
L -arginine transport ...systems in the human placental
syncytiotrophoblast across gestation using purified microvillous (MVM)
and basal (BM) plasma membrane vesicles. In MVM from first-trimester
and term placentas, L -arginine transport was by systems
y + and y + L. In BM (term placentas), however,
there was evidence for system y + L only. The Michaelis
constant of system y + L was significantly lower ( P < 0.05) in first-trimester compared with term MVM and lower in term
MVM compared with BM ( P < 0.05). There was no functional
evidence for system b 0+ in term MVM or BM. Cationic amino
acid transporter (CAT) 1, CAT 4, and 4F2hc were detected using RT-PCR
in placentas throughout gestation. rBAT was not detected in term
placentas. An ~85-kDa and an ~135-kDa protein was detected by
Western blotting in MVM under reducing and nonreducing conditions,
respectively, consistent with the 4F2hc monomer and the 4F2hc-light
chain dimer, and their expression was significantly higher ( P < 0.05) in term compared with first-trimester MVM. These proteins
were not detected in BM despite functional evidence for system
y + L. These data suggest different roles for 4F2hc in the
development and polarization of cationic amino acid transporters in the syncytiotrophoblast.
CAT 1; CAT 4; 4F2hc; rBAT; L -arginine; gestational
change