Summary of findings 4. Cell salvage compared to no cell salvage in cardiovascular (with bypass) surgeries.
| Cell salvage compared to no cell salvage in cardiovascular (with bypass) surgeries | ||||||
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Patient or population: cardiovascular (with bypass) surgeries Setting: hospital Intervention: cell salvage Comparison: no cell salvage | ||||||
| Outcomes | Anticipated absolute effects* (95% CI) | Relative effect (95% CI) | № of participants (studies) | Certainty of the evidence (GRADE) | Comments | |
| Risk with no cell salvage | Risk with cell salvage | |||||
| Transfusions (during hospital stay) | 630 per 1000 | 510 per 1000 (460 to 560) | RR 0.81 (0.73 to 0.89) | 2676 (25 RCTs) | ⨁⨁◯◯ Lowa,b | There may be an impact from cell salvage in reducing the risk of requiring allogeneic transfusion |
| Volume of transfusion (units) (PPT) (during hospital stay) | The mean volume of transfusion (units) (PPT) ranged from 0.75 to 7.15 units | MD 0.8 lower (1.21 lower to 0.4 lower) | ‐ | 1264 (16 RCTs) | ⨁◯◯◯ Very lowa,c,d | Very low‐certainty evidence means we are uncertain whether cell salvage has an impact on the volume of transfusion required PPT |
| Mortality (up to 90 days) | 22 per 1000 | 19 per 1000 (11 to 33) | RR 0.86 (0.50 to 1.48) | 2491 (21 RCTs) | ⨁◯◯◯ Very lowa,e | Very low‐certainty evidence means we are uncertain whether cell salvage has an impact on mortality risk |
| DVT (up to 90 days) | 0 per 1000 | 0 per 1000 (0 to 0) | RD 0.00 (‐0.12 to 0.12) | 30 (1 RCT) | ⨁◯◯◯ Very lowa,f | Very low‐certainty evidence means we are uncertain whether cell salvage has an impact on DVT risk |
| Infection (up to 90 days) | 94 per 1000 | 110 per 1000 (78 to 152) | RR 1.16 (0.83 to 1.61) | 1231 (8 RCTs) | ⨁⨁◯◯ Lowg,h | There may be no difference between cell salvage use and no cell salvage use for infection risk |
| MI (up to 90 days) | 34 per 1000 | 29 per 1000 (16 to 52) | POR 0.86 (0.47 to 1.58)i | 1376 (9 RCTs) | ⨁◯◯◯ Very lowe,g | Very low‐certainty evidence means we are uncertain whether cell salvage has an impact on MI risk |
| CVA (stroke) (up to 90 days) | 30 per 1000 | 16 per 1000 (7 to 37) | RR 0.54 (0.23 to 1.24) | 1018 (5 RCTs) | ⨁⨁⨁◯ Moderateh | There is probably no impact of cell salvage on CVA risk |
| *The risk in the intervention group (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI). CI: confidence interval; CVA: cerebrovascular accident; DVT: deep vein thrombosis; MD: mean difference; MI: myocardial infarction; MID: minimally important difference; OIS: optimal information size; POR: Peto odds ratio; PPT: per person transfused; RD: risk difference; ROB: risk of bias; RR: risk ratio; SD: standard deviation | ||||||
| GRADE Working Group grades of evidence High certainty: we are very confident that the true effect lies close to that of the estimate of the effect. Moderate certainty: we are moderately confident in the effect estimate: the true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different. Low certainty: our confidence in the effect estimate is limited: the true effect may be substantially different from the estimate of the effect. Very low certainty: we have very little confidence in the effect estimate: the true effect is likely to be substantially different from the estimate of effect. | ||||||
aDowngraded once for ROB due to assessment of unclear and low risk in most domains (mostly unclear) bDowngraded once for inconsistency: I2 = 64%, moderate heterogeneity cDowngraded twice for inconsistency: I2 = 91%, high heterogeneity dMID calculated as +/‐0.5*SD in control group = +/‐0.5*1.704 eDowngraded twice for imprecision: CI crosses both boundaries for MID (0.8 to 1.25) fDowngraded twice for imprecision due to small sample size, below OIS for this outcome gDowngraded once for ROB as most studies were at overall low or unclear risk, with some high ROB for randomisation and blinding, though these were in studies contributing less weight hDowngraded once for imprecision: CI crosses one boundary for MID (0.8 to 1.25) iPeto OR used due to low event rate in both groups (< 5%)