Preoperative statin therapy for adults undergoing cardiac surgery.

Despite significant advances in surgical techniques and perioperative care, people undertaking cardiac surgery due to cardiovascular disease are more prone to the development of postoperative adverse events. Statins (5-hydroxy-3-methylglutaryl-co-enzyme A (HMG-CoA) reductase inhibitors) are well-known for their anti-inflammatory and antioxidant effects and are established for primary and secondary prevention of coronary artery disease. In addition, statins are thought to have clinical benefits in perioperative outcomes in people undergoing cardiac surgery. This review is an update of a review that was first published in 2012 and updated in 2015. To evaluate the benefits and harms of preoperative statin therapy in adults undergoing cardiac surgery compared to standard of care or placebo. We performed a search of the Cochrane Central Register of Controlled Trials (CENTRAL) (Issue 9, 2023), Ovid MEDLINE (1980 to 14 September 2023), and Ovid Embase (1980 to 2023 (week 36)). We applied no language restrictions. We included all randomised controlled trials (RCTs) comparing any statin treatment before cardiac surgery, for any given duration and dose, versus no preoperative statin therapy (standard of care) or placebo. We excluded trials without a registered trial protocol and trials without approval by an institutional ethics committee. We used standard Cochrane methodology. Primary outcomes were short-term mortality and major adverse cardiovascular events. Secondary outcomes were myocardial infarction, atrial fibrillation, stroke, renal failure, length of intensive care unit (ICU) stay, length of hospital stay and adverse effects related to statin therapy. We reported effect measures as risk ratios (RRs) or mean differences (MDs) with corresponding 95% confidence intervals (CIs). We used the RoB 1 tool to assess the risk of bias in included trials, and GRADE to assess the certainty of the evidence. We identified eight RCTs (five new to this review) including 5592 participants. Pooled analysis showed that statin treatment before surgery may result in little to no difference in the risk of postoperative short-term mortality (RR 1.36, 95% CI 0.72 to 2.59; I2 = 0%; 6 RCTs, 5260 participants; low-certainty evidence; note 2 RCTs reported 0 events in both groups so RR calculated from 4 RCTs with 5143 participants). We are very uncertain about the effect of statins on major adverse cardiovascular events (RR 0.93, 95% CI 0.77 to 1.13; 1 RCT, 2406 participants; very low-certainty evidence). Statins probably result in little to no difference in myocardial infarction (RR 0.88, 95% CI 0.73 to 1.06; I2 = 0%; 5 RCTs, 4645 participants; moderate-certainty evidence), may result in little to no difference in atrial fibrillation (RR 0.87, 95% CI 0.72 to 1.05; I2 = 60%; 8 RCTs, 5592 participants; low-certainty evidence), and may result in little to no difference in stroke (RR 1.47, 95% CI 0.90 to 2.40; I2 = 0%; 4 RCTs, 5143 participants; low-certainty evidence). We are very uncertain about the effect of statins on renal failure (RR 1.04, 95% CI 0.80 to 1.34; I2 = 57%; 4 RCTs, 4728 participants; very low-certainty evidence). Additionally, statins probably result in little to no difference in length of ICU stay (MD 1.40 hours, 95% CI -1.62 to 4.41; I2 = 43%; 3 RCTs, 4528 participants; moderate-certainty evidence) and overall hospital stay (MD -0.31 days, 95% CI -0.64 to 0.03; I2 = 84%; 5 RCTs, 4788 participants; moderate-certainty evidence). No study had any individual risk of bias domain classified as high. However, two studies were at high risk of bias overall given the classification of unclear risk of bias in three domains. In this updated Cochrane review, we found no evidence that statin use in the perioperative period of elective cardiac surgery was associated with any clinical benefit or worsening, when compared with placebo or standard of care. Compared with placebo or standard of care, statin use probably results in little to no difference in MIs, length of ICU stay and overall hospital stay; and may make little to no difference to mortality, atrial fibrillation and stroke. We are very uncertain about the effects of statins on major harmful cardiac events and renal failure. The certainty of the evidence validating this finding varied from moderate to very low, depending on the outcome. Future trials should focus on assessing the impact of statin therapy on mortality and major adverse cardiovascular events.

Marques Antunes M ，Nunes-Ferreira A ，Duarte GS ，Gouveia E Melo R ，Sucena Rodrigues B ，Guerra NC ，Nobre A ，Pinto FJ ，Costa J ，Caldeira D ... -  《Cochrane Database of Systematic Reviews》

Interventions to prevent surgical site infection in adults undergoing cardiac surgery.

Surgical site infection (SSI) is a common type of hospital-acquired infection and affects up to a third of patients following surgical procedures. It is associated with significant mortality and morbidity. In the United Kingdom alone, it is estimated to add another £30 million to the cost of adult cardiac surgery. Although generic guidance for SSI prevention exists, this is not specific to adult cardiac surgery. Furthermore, many of the risk factors for SSI are prevalent within the cardiac surgery population. Despite this, there is currently no standard of care for SSI prevention in adults undergoing cardiac surgery throughout the preoperative, intraoperative and postoperative periods of care, with variations in practice existing throughout from risk stratification, decontamination strategies and surveillance. Primary objective: to assess the clinical effectiveness of pre-, intra-, and postoperative interventions in the prevention of cardiac SSI. (i) to evaluate the effects of SSI prevention interventions on morbidity, mortality, and resource use; (ii) to evaluate the effects of SSI prevention care bundles on morbidity, mortality, and resource use. We searched the Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library, MEDLINE (Ovid, from inception) and Embase (Ovid, from inception) on 31 May 2021. gov and the WHO International Clinical Trials Registry Platform (ICTRP) were also searched for ongoing or unpublished trials on 21 May 2021. No language restrictions were imposed. We included RCTs evaluating interventions to reduce SSI in adults (≥ 18 years of age) who have undergone any cardiac surgery. We followed the methods as per our published Cochrane protocol. Our primary outcome was surgical site infection. Our secondary outcomes were all-cause mortality, reoperation for SSI, hospital length of stay, hospital readmissions for SSI, healthcare costs and cost-effectiveness, quality of life (QoL), and adverse effects. We used the GRADE approach to assess the certainty of evidence. A total of 118 studies involving 51,854 participants were included. Twenty-two interventions to reduce SSI in adults undergoing cardiac surgery were identified. The risk of bias was judged to be high in the majority of studies. There was heterogeneity in the study populations and interventions; consequently, meta-analysis was not appropriate for many of the comparisons and these are presented as narrative summaries. We focused our reporting of findings on four comparisons deemed to be of great clinical relevance by all review authors. Decolonisation versus no decolonisation Pooled data from three studies (n = 1564) using preoperative topical oral/nasal decontamination in all patients demonstrated an uncertain direction of treatment effect in relation to total SSI (RR 0.98, 95% CI 0.70 to 1.36; I2 = 0%; very low-certainty evidence). A single study reported that decolonisation likely results in little to no difference in superficial SSI (RR 1.35, 95% CI 0.84 to 2.15; moderate-certainty evidence) and a reduction in deep SSI (RR 0.36, 95% CI 0.17 to 0.77; high-certainty evidence). The evidence on all-cause mortality from three studies (n = 1564) is very uncertain (RR 0.66, 95% CI 0.24 to 1.84; I2 = 49%; very low-certainty evidence). A single study (n = 954) demonstrated that decolonisation may result in little to no difference in hospital readmission for SSI (RR 0.80, 95% CI 0.44 to 1.45; low-certainty evidence). A single study (n = 954) reported one case of temporary discolouration of teeth in the decolonisation arm (low-certainty-evidence. Reoperation for SSI was not reported. Tight glucose control versus standard glucose control Pooled data from seven studies (n = 880) showed that tight glucose control may reduce total SSI, but the evidence is very uncertain (RR 0.41, 95% CI 0.19 to 0.85; I2 = 29%; numbers need to treat to benefit (NNTB) = 13; very-low certainty evidence). Pooled data from seven studies (n = 3334) showed tight glucose control may reduce all-cause mortality, but the evidence is very uncertain (RR 0.61, 95% CI 0.41 to 0.91; I2 = 0%; very low-certainty evidence). Based on four studies (n = 2793), there may be little to no difference in episodes of hypoglycaemia between tight control vs. standard control, but the evidence is very uncertain (RR 2.12, 95% CI 0.51 to 8.76; I2 = 72%; very low-certainty evidence). No studies reported superficial/deep SSI, reoperation for SSI, or hospital readmission for SSI. Negative pressure wound therapy (NPWT) versus standard dressings NPWT was assessed in two studies (n = 144) and it may reduce total SSI, but the evidence is very uncertain (RR 0.17, 95% CI 0.03 to 0.97; I2 = 0%; NNTB = 10; very low-certainty evidence). A single study (n = 80) reported reoperation for SSI. The relative effect could not be estimated. The certainty of evidence was judged to be very low. No studies reported superficial/deep SSI, all-cause mortality, hospital readmission for SSI, or adverse effects. Topical antimicrobials versus no topical antimicrobials Five studies (n = 5382) evaluated topical gentamicin sponge, which may reduce total SSI (RR 0.62, 95% CI 0.46 to 0.84; I2 = 48%; NNTB = 32), superficial SSI (RR 0.60, 95% CI 0.37 to 0.98; I2 = 69%), and deep SSI (RR 0.67, 95% CI 0.47 to 0.96; I2 = 5%; low-certainty evidence. Four studies (n = 4662) demonstrated that topical gentamicin sponge may result in little to no difference in all-cause mortality, but the evidence is very uncertain (RR 0.96, 95% CI 0.65 to 1.42; I2 = 0%; very low-certainty evidence). Reoperation for SSI, hospital readmission for SSI, and adverse effects were not reported in any included studies. This review provides the broadest and most recent review of the current evidence base for interventions to reduce SSI in adults undergoing cardiac surgery. Twenty-one interventions were identified across the perioperative period. Evidence is of low to very low certainty primarily due to significant heterogeneity in how interventions were implemented and the definitions of SSI used. Knowledge gaps have been identified across a number of practices that should represent key areas for future research. Efforts to standardise SSI outcome reporting are warranted.

Cardiothoracic Interdisciplinary Research Network ，Rogers LJ ，Vaja R ，Bleetman D ，Ali JM ，Rochon M ，Sanders J ，Tanner J ，Lamagni TL ，Talukder S ，Quijano-Campos JC ，Lai F ，Loubani M ，Murphy GJ ... -  《Cochrane Database of Systematic Reviews》

Treatment for women with postpartum iron deficiency anaemia.

Postpartum iron deficiency anaemia is caused by antenatal iron deficiency or excessive blood loss at delivery and might affect up to 50% of labouring women in low- and middle-income countries. Effective and safe treatment during early motherhood is important for maternal well-being and newborn care. Treatment options include oral iron supplementation, intravenous iron, erythropoietin, and red blood cell transfusion. To assess the benefits and harms of the available treatment modalities for women with postpartum iron deficiency anaemia. These include intravenous iron, oral iron supplementation, red blood cell transfusion, and erythropoietin. A Cochrane Information Specialist searched for all published, unpublished, and ongoing trials, without language or publication status restrictions. We searched databases including CENTRAL, MEDLINE, Embase, CINAHL, LILACS, WHO ICTRP, and ClinicalTrials.gov, together with reference checking, citation searching, and contact with study authors to identify eligible studies. We applied date limits to retrieve new records since the last search on 9 April 2015 until 11 April 2024. We included published, unpublished, and ongoing randomised controlled trials (RCTs) that compared treatments for postpartum iron deficiency anaemia with placebo, no treatment, or alternative treatments. Cluster-randomised trials were eligible for inclusion. We included RCTs regardless of blinding. Participants were women with postpartum haemoglobin ≤ 12 g/dL, treated within six weeks after childbirth. We excluded non-randomised, quasi-randomised, and cross-over trials. The critical outcomes of this review were maternal mortality and fatigue. The important outcomes included persistent anaemia symptoms, persistent postpartum anaemia, psychological well-being, infections, compliance with treatment, breastfeeding, length of hospital stay, serious adverse events, anaphylaxis or evidence of hypersensitivity, flushing/Fishbane reaction, injection discomfort/reaction, constipation, gastrointestinal pain, number of red blood cell transfusions, and haemoglobin levels. We assessed risk of bias in the included studies using the Cochrane RoB 1 tool. Two review authors independently performed study screening, risk of bias assessment, and data extraction. We contacted trial authors for supplementary data when necessary. We screened all trials for trustworthiness and scientific integrity using the Cochrane Trustworthiness Screening Tool. We conducted meta-analyses using a fixed-effect model whenever feasible to synthesise outcomes. In cases where data were not suitable for meta-analysis, we provided a narrative summary of important findings. We evaluated the overall certainty of the evidence using GRADE. We included 33 RCTs with a total of 4558 postpartum women. Most trials were at high risk of bias for several risk of bias domains. Most of the evidence was of low or very low certainty. Imprecision due to few events and risk of bias due to lack of blinding were the most important factors. Intravenous iron versus oral iron supplementation The evidence is very uncertain about the effect of intravenous iron on mortality (risk ratio (RR) 2.95, 95% confidence interval (CI) 0.12 to 71.96; P = 0.51; I² = not applicable; 3 RCTs; 1 event; 572 women; very low-certainty evidence). One woman died of cardiomyopathy, and another developed arrhythmia, both in the groups treated with intravenous iron. Intravenous iron probably results in a slight reduction in fatigue within 8 to 28 days (standardised mean difference -0.25, 95% CI -0.42 to -0.07; P = 0.006; I² = 47%; 2 RCTs; 515 women; moderate-certainty evidence). Breastfeeding was not reported. Oral iron probably increases the risk of constipation compared to intravenous iron (RR 0.12, 95% CI 0.06 to 0.21; P < 0.001; I² = 0%; 10 RCTs; 1798 women; moderate-certainty evidence). The evidence is very uncertain about the effect of intravenous iron on anaphylaxis or hypersensitivity (RR 2.77, 95% CI 0.31 to 24.86; P = 0.36; I² = 0%; 12 RCTs; 2195 women; very low-certainty evidence). Three women treated with intravenous iron experienced anaphylaxis or hypersensitivity. The trials that reported on haemoglobin at 8 to 28 days were too heterogeneous to pool. However, 5 of 6 RCTs favoured intravenous iron, with mean changes in haemoglobin ranging from 0.73 to 2.10 g/dL (low-certainty evidence). Red blood cell transfusion versus intravenous iron No women died in the only trial that reported on mortality (1 RCT; 7 women; very low-certainty evidence). The evidence is very uncertain about the effect of red blood cell transfusion on fatigue at 8 to 28 days (mean difference (MD) 1.20, 95% CI -2.41 to 4.81; P = 0.51; I² = not applicable; 1 RCT; 13 women; very low-certainty evidence) and breastfeeding more than six weeks postpartum (RR 0.43, 95% CI 0.12 to 1.57; P = 0.20; I² = not applicable; 1 RCT; 13 women; very low-certainty evidence). Constipation and anaphylaxis were not reported. Red blood cell transfusion may result in little to no difference in haemoglobin within 8 to 28 days (MD -1.00, 95% CI -2.02 to 0.02; P = 0.05; I² = not applicable; 1 RCT; 12 women; low-certainty evidence). Intravenous iron and oral iron supplementation versus oral iron supplementation Mortality and breastfeeding were not reported. One trial reported a greater improvement in fatigue in the intravenous and oral iron group, but the effect size could not be calculated (1 RCT; 128 women; very low-certainty evidence). Intravenous iron and oral iron may result in a reduction in constipation compared to oral iron alone (RR 0.21, 95% CI 0.07 to 0.69; P = 0.01; I² = not applicable; 1 RCT; 128 women; low-certainty evidence). There were no anaphylaxis or hypersensitivity events in the trials (2 RCTs; 168 women; very low-certainty evidence). Intravenous iron and oral iron may result in little to no difference in haemoglobin (g/dL) at 8 to 28 days (MD 0.00, 95% CI -0.48 to 0.48; P = 1.00; I² = not applicable; 1 RCT; 60 women; low-certainty evidence). Red blood cell transfusion versus no transfusion Mortality, fatigue at day 8 to 28, constipation, anaphylaxis, and haemoglobin were not reported. Red blood cell transfusion may result in little to no difference in breastfeeding more than six weeks postpartum (RR 0.91, 95% CI 0.78 to 1.07; P = 0.24; I² = not applicable; 1 RCT; 297 women; low-certainty evidence). Oral iron supplementation versus placebo or no treatment Mortality, fatigue, breastfeeding, constipation, anaphylaxis, and haemoglobin were not reported. Two trials reported on gastrointestinal symptoms, but did not report results by study arm. Intravenous iron probably reduces fatigue slightly in the early postpartum weeks (8 to 28 days) compared to oral iron tablets, but probably results in little to no difference after four weeks. It is very uncertain if intravenous iron has an effect on mortality and anaphylaxis/hypersensitivity. Breastfeeding was not reported. Intravenous iron may increase haemoglobin slightly more than iron tablets, but the data were too heterogeneous to pool. However, changes in haemoglobin levels are a surrogate outcome, and treatment decisions should preferentially be based on patient-relevant outcomes. Iron tablets probably result in a large increase in constipation compared to intravenous iron. The effect of red blood cell transfusion compared to intravenous iron on mortality, fatigue, and breastfeeding is very uncertain. No studies reported on constipation or anaphylaxis/hypersensitivity. Red blood cell transfusion may result in little to no difference in haemoglobin at 8 to 28 days. The effect of intravenous iron and oral iron supplementation on mortality, fatigue, breastfeeding, and anaphylaxis/hypersensitivity is very uncertain or unreported. Intravenous iron and oral iron may result in a reduction in constipation compared to oral iron alone, and in little to no difference in haemoglobin. The effect of red blood cell transfusion compared to non-transfusion on mortality, fatigue, constipation, anaphylaxis/hypersensitivity, and haemoglobin is unreported. Red blood cell transfusion may result in little to no difference in breastfeeding. The effect of oral iron supplementation on mortality, fatigue, breastfeeding, constipation, anaphylaxis/hypersensitivity, and haemoglobin is unreported. This Cochrane review had no dedicated funding. Protocol and previous versions are available: Protocol (2013) [DOI: 10.1002/14651858.CD010861] Original review (2004) [DOI: 10.1002/14651858.CD004222.pub2] Review update (2015) [DOI: 10.1002/14651858.CD010861.pub2].

Jensen MCH ，Holm C ，Jørgensen KJ ，Schroll JB ... -  《Cochrane Database of Systematic Reviews》

Prophylactic use of inotropic agents for the prevention of low cardiac output syndrome and mortality in adults undergoing cardiac surgery.

As the burden of cardiovascular disease grows, so does the number of cardiac surgeries. Surgery is increasingly performed on older people with comorbidities who are at higher risk of developing perioperative complications such as low cardiac output state (LCOS). Surgery-associated LCOS represents a serious pathology responsible for substantial morbidity and mortality. Prevention of LCOS is a critical and worthwhile aim to further improve the outcome and effectiveness of cardiac surgery. However, guidelines consistently report a lack of evidence for pharmacological LCOS prophylaxis. To assess the benefits and harms of the prophylactic use of any inotropic agent to prevent low cardiac output and associated morbidity and mortality in adults undergoing cardiac surgery. We identified trials (without language restrictions) via systematic searches of CENTRAL, MEDLINE, Embase, and CPCI-S Web of Science in October 2022. We checked reference lists from primary studies and review articles for additional references. We also searched two registers of ongoing trials. We included randomised controlled trials (RCTs) enrolling adults who underwent cardiac surgery and were prophylactically treated with one or multiple inotropic agent(s) in comparison to any type of control (i.e. standard cardiac care, placebo, other inotropic agents). We used established methodological procedures according to Cochrane standards. Two review authors independently extracted data and assessed risk of bias according to a pre-defined protocol. On request, we obtained a reply and additional information from only one of the included study authors. We used the five GRADE considerations (study limitations, consistency of effect, imprecision, indirectness, and publication bias) to assess the certainty of evidence from the studies that contributed data to the meta-analyses for the pre-specified outcomes. Based on the identified studies, there were seven comparison groups: amrinone versus placebo, dopamine versus placebo, milrinone versus placebo, levosimendan versus dobutamine, levosimendan versus milrinone, levosimendan versus standard cardiac care, and levosimendan versus placebo. We identified 29 eligible studies, including 3307 individuals, and four ongoing studies. In general, confidence in the results of the analysed studies was reduced due to relevant study limitations, imprecision, or inconsistency. Domains of concern encompassed inadequate methods of sequence generation and lack of blinding. The majority of trials were small, with only a few included participants, and investigated the prophylactic use of levosimendan. Our meta-analyses showed that levosimendan as compared to placebo may reduce the risk of LCOS (risk ratio (RR) 0.43, 95% confidence interval (CI) 0.25 to 0.74; I2 = 66%; 1724 participants, 6 studies; GRADE: low) and probably reduces all-cause mortality (RR 0.65, 95% CI 0.43 to 0.97; I2 = 11%; 2347 participants, 14 studies; GRADE: moderate). This translates into a number needed to treat for an additional beneficial outcome (NNTB) of 8 to prevent one event of LCOS post surgery and of 44 to prevent one death at 30 days. Subgroup analyses revealed that the beneficial effects of levosimendan were predominantly observed in preoperative drug administration. Our meta-analyses further indicated that levosimendan as compared to placebo may shorten the length of intensive care unit (ICU) stay (mean difference -1.00 days, 95% CI -1.63 to -0.37; 572 participants, 7 studies; GRADE: very low) and the duration of mechanical ventilation (mean difference -8.03 hours, 95% CI -13.17 to -2.90; 572 participants, 7 studies; GRADE: very low) but the evidence is very uncertain. The risk of adverse events did not clearly differ between levosimendan and placebo groups (cardiogenic shock: RR 0.65, 95% CI 0.40 to 1.05; I2 = 0%; 1212 participants, 3 studies; GRADE: high; atrial fibrillation: RR 1.02, 95% CI 0.82 to 1.27; I2 = 60%; 1934 participants, 11 studies; GRADE: very low; perioperative myocardial infarction: RR 0.89, 95% CI 0.61 to 1.31; I2 = 13%; 1838 participants, 8 studies; GRADE: moderate; non-embolic stroke or transient ischaemic attack: RR 0.89, 95% CI 0.58 to 1.38; I2 = 0%; 1786 participants, 8 studies; GRADE: moderate). However, levosimendan as compared to placebo might reduce the number of participants requiring mechanical circulatory support (RR 0.47, 95% CI 0.24 to 0.91; I2 = 74%; 1881 participants, 10 studies; GRADE: low). There was no conclusive evidence on the effect of levosimendan compared to standard cardiac care on LCOS (RR 0.49, 95% CI 0.14 to 1.73; I2 = 59%; 208 participants, 3 studies; GRADE: very low), all-cause mortality (RR 0.37, 95% CI 0.13 to 1.04; I2 = 0%; 208 participants, 3 studies; GRADE: low), adverse events (cardiogenic shock: RR 0.62, 95% CI 0.22 to 1.81; 128 participants, 1 study; GRADE: very low; atrial fibrillation: RR 0.40, 95% CI 0.11 to 1.41; I2 = 60%; 188 participants, 2 studies; GRADE: very low; perioperative myocardial infarction: RR 0.62, 95% CI 0.22 to 1.81; 128 participants, 1 study; GRADE: very low; non-embolic stroke or transient ischaemic attack: RR 0.56, 95% CI 0.27 to 1.18; 128 participants, 1 study; GRADE: very low), length of ICU stay (mean difference 0.33 days, 95% CI -1.16 to 1.83; 80 participants, 2 studies; GRADE: very low), the duration of mechanical ventilation (mean difference -3.40 hours, 95% CI -11.50 to 4.70; 128 participants, 1 study; GRADE: very low), and the number of participants requiring mechanical circulatory support (RR 0.88, 95% CI 0.50 to 1.55; I2 = 0%; 208 participants, 3 studies; GRADE: low). Prophylactic treatment with levosimendan may reduce the incidence of LCOS and probably reduces associated mortality in adult patients undergoing cardiac surgery when compared to placebo only. Conclusions on the benefits and harms of other inotropic agents cannot be drawn due to limited study data. Given the limited evidence available, there is an unmet need for large-scale, well-designed randomised trials. Future studies of levosimendan ought to be designed to derive potential benefit in specific patient groups and surgery types, and the optimal administration protocol.

Gayatri D ，Tongers J ，Efremov L ，Mikolajczyk R ，Sedding D ，Schumann J ... -  《Cochrane Database of Systematic Reviews》

Cell salvage for the management of postpartum haemorrhage.

Postpartum haemorrhage (PPH), defined as a blood loss of 500 mL or more within 24 hours of birth, is the leading global cause of maternal morbidity and mortality. Allogenic blood transfusions are a critical component of PPH management, yet are often unfeasible, particularly in resource-poor settings where maternal morbidity is highest. Autologous cell salvage in the management of PPH has been proposed to combat limitations in access to allogenic blood and potential transfusion-related risks. This review examines the benefits and harms of using cell salvage for pregnant women during birth. To assess the benefits and harms of cell salvage when used during birth. We searched the CENTRAL, MEDLINE, Ovid Embase, and Global Index Medicus databases and the ICTRP and ClinicalTrials.gov trials registers. We also carried out reference checking and citation searching, and contacted study authors to identify all relevant studies. The latest search date was 8 February 2024. We included randomised controlled trials (RCTs) in pregnant women (24 weeks or more gestation) comparing use of cell salvage following caesarean or vaginal birth with routine care (defined as no cell salvage). We did not place any restrictions on mode of birth, ethnicity, race, socioeconomic status, education level, or place of residence. Critical outcomes for this review were risk of allogenic blood transfusion, risk of transfusion-related adverse reactions, risk of haemorrhage, transfer to higher level of care, length of hospitalisation, length of operation, and risk of sepsis. Important outcomes were estimated blood loss, blood loss ≥ 500 mL, blood loss ≥ 1000 mL, use of additional uterotonics or tranexamic acid, maternal death, postpartum haemoglobin concentration, change in haemoglobin, major surgery including hysterectomy, future major surgery, end-organ dysfunction or failure, amniotic fluid embolism, side effects, clotting abnormalities, maternal experience/satisfaction, maternal well-being, and breastfeeding. We assessed risk of bias using the Cochrane risk of bias tool (RoB 1) for each critical outcome from each RCT. We conducted a meta-analysis for each outcome where data were available from more than one study using a random-effects model. If data could not be analysed using meta-analysis, we synthesised results narratively using the Synthesis Without Meta-analysis (SWiM) guidance. We used GRADE to assess the certainty of evidence for each outcome. We included six RCTs with 3476 participants. All trials involved pregnant women having a caesarean birth. Three trials were conducted in high-income countries, and three were conducted in an upper-middle-income country. Allogenic blood transfusion Intraoperative cell salvage at caesarean birth may reduce the need for allogenic transfusions received by participants, although the 95% confidence interval (CI) includes the possibility of an increase in effect. Low-certainty evidence from three studies found the risk of donor transfusions was possibly lower in participants with cell salvage (risk ratio (RR) 0.45, 95% CI 0.15 to 1.33; P = 0.15, I2 = 33%; 3 RCTs, 3115 women; low-certainty evidence). The absolute risk of transfusion was very low in the studies (4% in women not treated with cell salvage and 2% in women treated with cell salvage). Transfusion-related adverse reactions The evidence is very uncertain about the risk of transfusion-related adverse reactions in participants with intraoperative cell salvage (RR 0.48, 95% CI 0.09 to 2.62; P = 0.39; 4 RCTs, 3304 women; very low-certainty evidence). Haemorrhage Two studies reported risk of haemorrhage and found that there was probably no difference between arms (RR 0.88, 95% CI 0.67 to 1.15; P = 0.36, I² = 0%; 2 RCTs, 3077 women; moderate-certainty evidence). Length of hospitalisation The evidence is very uncertain about whether interoperative cell salvage at caesarean birth affects length of hospitalisation. Three studies reported length of hospitalisation (MD -2.02 days, 95% CI -4.73 to 0.70; P = 0.15, I2 = 100%; 3 RCTs, 3174 women; very low-certainty evidence). Length of operation Two studies reported on length of operation. However, meta-analysis was not possible due to statistical heterogeneity and divergence of study findings; the direction of effect could not be determined. We evaluated the evidence as very low certainty. Sepsis One study reported risk of sepsis, finding that there was possibly no difference between arms (RR 1.00, 95% CI 0.43 to 2.29; P = 0.99; 1 RCT, 2990 women; low-certainty evidence). Estimated blood loss Cell salvage at caesarean birth may reduce blood loss. Two studies reported that estimated blood loss was possibly lower in women who had cell salvage compared to those who did not (MD -113.59 mL, 95% CI -130.41 to -96.77; P < 0.00001, I2 = 0%; 2 RCTs, 246 women; low-certainty evidence). Postpartum haemoglobin concentration Cell salvage at caesarean birth may increase day one postpartum haemoglobin. Three studies reported day one postpartum haemoglobin levels (MD 6.14 g/L, 95% CI 1.62 to 10.65; P = 0.008, I2 = 97%; 3 RCTs, 3070 women; low-certainty evidence). Amniotic fluid embolism Three trials reported risk of amniotic fluid embolism and no cases were observed (n = 3226 women). Cell salvage may reduce the need for allogenic blood transfusion, may reduce blood loss, and may increase day one postpartum haemoglobin in pregnant women having caesarean birth (low certainty). Cell salvage may make little to no difference to the risk of sepsis (low certainty) and probably makes little to no difference to the risk of haemorrhage (moderate certainty). The effect of cell salvage on risk of transfusion-related adverse reactions is very uncertain. The effect of cell salvage on the length of hospital stay was both clinically and statistically heterogenous, with a very low certainty of evidence. The effect of cell salvage on length of operation is divergent and meta-analysis was not possible due to significant statistical heterogeneity; the evidence is of very low certainty. No cases of amniotic fluid embolism were reported among the included trials. Studies in low- and middle-income settings are needed. This review had no dedicated funding. This review was registered with PROSPERO (CRD42024554204).

Dey T ，Brown D ，Cole MG ，Hill RA ，Chaplin M ，Huffstetler HE ，Curtis F ... -  《Cochrane Database of Systematic Reviews》