Evidence Cornered: Transfusion Evidence Summary – Platelet transfusion before CVC placement in patients with thrombocytopenia (PACER trial)

Clinical


| INTRODUCTION
[3][4][5][6] The routine use of ultrasound in CVC insertion has reduced bleeding complications, 7 and some studies have shown a harmful effect of platelet transfusions. 8This study aims to see whether, in this context, omission of prophylactic platelet transfusion increases the risk of CVC-related bleeding in patients with platelet counts 10-50 Â 10 9 /L.

Evidence Box
Study design: Single-blinded, randomised controlled noninferiority trial.
No. of patients: 411 CVC placements randomised.373 included in the per-protocol analysis.
• CVC due to be in place for >24 h.

| Summary of study findings
Grade 2-4 bleeding occurred in 4.8% of the transfusion group, and 11.9% of the non-transfusion group.Most bleeding was Grade 2, with no Grade 4 events.In subgroup analysis, the bleeding risk was higher for haematology inpatients than on ICU, and for subclavian CVCs (Table 1).

| Limitations
• The authors state that 18% of inpatients in the Netherlands have a CVC inserted, which is higher than in the UK. 9 Subclavian CVCs accounted for 37% of lines inserted.The increased bleeding risk associated with these represented the majority of excess bleeding in this study, so findings may not be generalisable to countries where this site is not commonly used.
• The majority of bleeding in this study was Grade 2, which settled with conservative measures.It is unclear whether this is clinically significant and offsets the risks and financial costs of transfusion.
• The authors conclude that they would consider giving platelet transfusions prior to CVC insertion for patients with platelets <30 Â 10 9 /L.It is unclear how this threshold was selected, given the numbers in the subgroup analysis were small and the effect of withholding transfusion in patients with platelet counts 10-20 Â 10 9 /L was not significant.They also suggest platelet transfusions should be considered for tunnelled line insertion, despite there being no evidence of a reduction in bleeding risk in this context.
• The overall rate of bleeding was higher than in other studies, likely due to its prospective nature and the site of CVC insertion.
• Further limitations of this study are discussed in this letter. 10

| Evidence in context
This is the first RCT of platelet transfusions prior to invasive procedures.
T A B L E 1 Results.
Use of therapeutic anticoagulation, history of acquired/ congenital bleeding disorder, INR >3 (changed from INR >1.5 mid-trial), <24 h from previous CVC placement.Comparison: 1:1 randomisationreceive a one-unit platelet transfusion before CVC placement or no platelet transfusion.Any [Correction added on 28 June 2024, after first online publication: The article title was corrected in this version.]type of CVC was permitted.The non-inferiority margin was set at 2.5% in the no transfusion group.Primary outcome: Grade 2-4 catheter-related bleeding within 24 h of CVC placement assessed according to this bleeding scale.Secondary outcomes: Grade 1 or >Grade 3 bleeding, Platelet/ red cell transfusions within 24 h, Hb/platelet count at 1 + 24 h, allergic transfusion reactions, TRALI, length of ICU/ hospital stay, inpatient mortality, financial costs.