T4P is a study designed to establish the safe optimal threshold for platelet count in procedures associated with critical illness. This trial is currently suspended at KCH due to the Synnovis Ransomware attack, and its effects on the transfusion service.
INCLUSION CRITERIA
Patients must meet all the inclusion criteria, and none of the exclusion criteria at the time of randomisation:
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Inclusion criteria:
1. Adult (aged ≥18 years)
2. Accepted for admission or admitted to a participating critical care unit
3. Platelet count <50x109/L
4. Planned to undergo a specified* low bleeding risk invasive procedure OR platelet transfusion being considered for an ‘other’ procedure
*Specified low bleeding risk invasive procedures include the following: • Central venous vascular catheter insertion (including vascular access for renal replacement therapy) • Paracentesis/superficial abdominal fluid collection drainage • Pleural aspiration
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‘Other’ procedures may be included if the clinician deems these to be a low bleeding risk invasive procedure and a platelet transfusion is being considered for the procedure. These include, but are not limited to, the following: • Arterial catheter insertion • Arterial or central venous catheter removal • Pleural drain • Interventional radiology (as defined by Society of Interventional Radiology guidelines) • Bronchoscopy with or without lavage • Wound dressing changes • Surgical procedures where the clinical team agree risk of bleeding is low, e.g. re-look laparotomy, or wound closure
EXCLUSION CRITERIA
1. Ongoing major haemorrhage requiring blood products and/or surgical/radiological intervention†
2. Intracranial haemorrhage within prior 72 hours†
3. Contra-indication to platelet transfusion (such as thrombotic microangiopathies; heparin-induced thrombocytopaenia; immune thrombocytopaenia; congenital platelet function defects)
4. Acute promyelocytic leukaemia (APML)
5. Known advance decision refusing blood/blood component transfusions (e.g. Jehovah’s Witnesses)
6. Death perceived as imminent or admission for palliation
7. Previously randomised into T4P
8. Fulfilled all the inclusion criteria and none of the other exclusion criteria ≥ 72 hours
†Exclusion criteria no. 1 and 2 are dynamic, and if resolved, the patient may be reconsidered for the trial. Patients receiving anticoagulation therapy or anti-platelet therapy will be included, with unit policies (other than platelet administration) followed prior to the procedure. Patients with platelet counts ≥50x109/L will be screened daily until recruitment, refusal or critical care unit discharge. Patients undergoing procedures not eligible for randomisation will remain available for inclusion where subsequent eligible procedures occur.
Study Information
The T4P study is a platelet threshold study and not a platelet target study.
The specialist team or critical care can order and administer platelets against a daily
platelet target uncoupled from the T4P trial- so the T4P allocation is only the trigger
for platelet COVER for ICU PROCEDURES.
Once the patient is randomised, they should keep the same procedure cover trigger
for the rest of the ICU admission
If a patient has a platelet count<50 and gets platelets for a clinical reason, they do not then
need a re-check of platelets prior to randomisation.
