Summary of findings of studies in which clinicians increased VWF levels to 0.50 IU/mL in patients with VWD undergoing minor surgery
| Outcome . | No. of participants . | No. of observational studies . | Total No. of surgeries . | Certainty of the evidence . | GRADE . | Impact . |
|---|---|---|---|---|---|---|
| Bleeding complications: hemorrhagic, postoperative bleeding | 278 | 6 | 281 | ⨁◯◯◯ | Very low*† | Proportion of surgeries in which there were bleeding complications, 11% (95% CI, 6%-19%). |
| Hemostasis during surgery: excellent or good; adequate, as judged by clinician | 88 | 3 | ⨁◯◯◯ | Very low* | Proportion of procedures in which hemostasis was judged as appropriate, 98% (95% CI, 91%-99%). | |
| No. of patients with need for additional hemostatic agents (postoperative factor replacement) | 13 | 1 | ⨁◯◯◯ | Very low*‡ | Proportion of participants who required postoperative factor replacement, 54% (7 of 13). Proportion who required continuous replacement, 38% (5 of 13). | |
| Hospitalization needed for performing the procedure | 13 | 1 | ⨁◯◯◯ | Very low* | In 1 study in which researchers report outcomes of 13 liver or percutaneous biopsies, all 13 patients had to be hospitalized for the procedure. | |
| No. of patients who needed transfusion | 51 | 3 | 54 | ⨁◯◯◯ | Very low*§ | Proportion of participants who needed transfusions, 2% (95% CI, 0%-50%). |
| Thrombotic serious AEs | 76 | 3 | 94 | ⨁◯◯◯ | Very low* | Three studies reported this outcome; no thrombotic events occurred in any of the 3 studies. |
| No. of patients who developed inhibitors or AEs | 39 | 2 | ⨁◯◯◯ | Very low*† | Proportion of patients who developed inhibitors, 2% (95% CI, 0%-21%). | |
| Several definitions provided for AEs | 133 | 4 | ⨁◯◯◯ | Very low* | Four studies reported AEs; 3 reported no allergic reactions (0 of 28 surgeries), no wound infections (0 of 11 surgeries), and no AEs (0 of 29 surgeries); 1 study reported a vasovagal episode that required hospitalization for observation in 1 of 65 patients. |
| Outcome . | No. of participants . | No. of observational studies . | Total No. of surgeries . | Certainty of the evidence . | GRADE . | Impact . |
|---|---|---|---|---|---|---|
| Bleeding complications: hemorrhagic, postoperative bleeding | 278 | 6 | 281 | ⨁◯◯◯ | Very low*† | Proportion of surgeries in which there were bleeding complications, 11% (95% CI, 6%-19%). |
| Hemostasis during surgery: excellent or good; adequate, as judged by clinician | 88 | 3 | ⨁◯◯◯ | Very low* | Proportion of procedures in which hemostasis was judged as appropriate, 98% (95% CI, 91%-99%). | |
| No. of patients with need for additional hemostatic agents (postoperative factor replacement) | 13 | 1 | ⨁◯◯◯ | Very low*‡ | Proportion of participants who required postoperative factor replacement, 54% (7 of 13). Proportion who required continuous replacement, 38% (5 of 13). | |
| Hospitalization needed for performing the procedure | 13 | 1 | ⨁◯◯◯ | Very low* | In 1 study in which researchers report outcomes of 13 liver or percutaneous biopsies, all 13 patients had to be hospitalized for the procedure. | |
| No. of patients who needed transfusion | 51 | 3 | 54 | ⨁◯◯◯ | Very low*§ | Proportion of participants who needed transfusions, 2% (95% CI, 0%-50%). |
| Thrombotic serious AEs | 76 | 3 | 94 | ⨁◯◯◯ | Very low* | Three studies reported this outcome; no thrombotic events occurred in any of the 3 studies. |
| No. of patients who developed inhibitors or AEs | 39 | 2 | ⨁◯◯◯ | Very low*† | Proportion of patients who developed inhibitors, 2% (95% CI, 0%-21%). | |
| Several definitions provided for AEs | 133 | 4 | ⨁◯◯◯ | Very low* | Four studies reported AEs; 3 reported no allergic reactions (0 of 28 surgeries), no wound infections (0 of 11 surgeries), and no AEs (0 of 29 surgeries); 1 study reported a vasovagal episode that required hospitalization for observation in 1 of 65 patients. |
The following outcomes were not reported in the studies: need for additional surgical procedures, mortality, inability to perform the surgery. The risk in the intervention group (and its 95% CI) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI). GRADE Working Group grade of evidence: 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.
These are case series, and there are no comparisons with other groups.
The CIs show that the proportion can be very small or not so small.
Very small number of patients.
The CIs are very wide and suggest that the proportion can be very small to very large.