Summary of findings for the main comparison. Cardiopulmonary interventions to decrease blood loss and blood transfusion requirements for liver resection.
| Cardiopulmonary intervention versus control for liver resection | ||||||
| Patient or population: patients with liver resection. Settings: secondary or tertiary care. Intervention: intervention versus control. | ||||||
| Outcomes | Illustrative comparative risks* (95% CI) | Relative effect (95% CI) | No of Participants (studies) | Quality of the evidence (GRADE) | Comments | |
| Assumed risk | Corresponding risk | |||||
| Control | Intervention versus control | |||||
| Serious adverse events ‐ Haemodilution versus control. | Study population | |||||
| 217 per 1000 | 219 per 1000 (124 to 391) | Rate ratio 1.01 (0.57 to 1.8) | 208 (2 studies) | ⊕⊝⊝⊝ very low1,2,3,4,5 | ||
| Number requiring allogeneic blood transfusion ‐ Low central venous pressure (CVP) versus control. | Study population | RR 0.66 (0.42 to 1.03) | 177 (3 studies) | ⊕⊝⊝⊝ very low1,3,4,5 | ||
| 303 per 1000 | 200 per 1000 (127 to 312) | |||||
| Number requiring allogeneic blood transfusion ‐ Haemodilution versus control. | Study population | RR 0.41 (0.25 to 0.66) | 233 (3 studies) | |||
| 347 per 1000 | 142 per 1000 (87 to 229) | |||||
| Red cell transfusion ‐ Low CVP versus control. | The mean red cell transfusion ‐ low CVP versus control in the intervention groups was 0.31 standard deviations lower (0.65 lower to 0.03 higher) | 135 (2 studies) | ⊕⊝⊝⊝ very low1,5,6,7 | SMD ‐0.31 (‐0.65 to 0.03) | ||
| Red cell transfusion ‐ Haemodilution versus control. | The mean red cell transfusion ‐ haemodilution versus control in the intervention groups was 0.33 standard deviations lower (0.63 to 0.03 lower) | 180 (3 studies) | ⊕⊝⊝⊝ very low1,5,6 | SMD ‐0.33 (‐0.63 to ‐0.03) | ||
| *The basis for the assumed risk was the mean control group risk across studies. The corresponding risk (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; RR: Risk ratio. | ||||||
| GRADE Working Group grades of evidence High quality: Further research is very unlikely to change our confidence in the estimate of effect. Moderate quality: Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate. Low quality: Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate. Very low quality: We are very uncertain about the estimate. | ||||||
1 Trials were of high risk of bias. 2 The seriousness of the outcomes was based on the study authors' judgement. 3 The confidence intervals overlap 1 and 0.75 or 1.25, or both. 4 Fewer than 300 events (in both groups). 5 There were few trials to assess whether there was any publication bias. 6 The I‐squared value was high. 7 There were less than 400 patients in both the groups together and the confidence intervals overlap 0 and ‐0.25 and/or +0.25.