Sometimes, medical practice in the setting of uncertainty simply turns out to be futile and low-value.
This is one of those times where we’ve probably been at least futile, and possibly harmful.
Life-threatening or critical intracranial bleeding in the setting of concomitant antiplatelet therapy frequently offers a dire prognosis. As part of our standard “don’t just stand there!” approach in Emergency Medicine, patients with ICH in this setting are frequently transfused platelets in an effort to provide untainted clotting substrate. This practice, however, has never been reinforced by substantiated evidence, and the pharmacokinetics of the antiplatelet agents suggests this strategy is unlikely to be efficacious.
This is the PATCH trial, a randomized, open-label trial conducted at 60 hospitals between 2009 and 2015, investigating the utility of platelet transfusion in the setting of ICH. Patients with normal baseline functional status and ICH while taking aspirin, clopidogrel, or dipyridamole were eligible for inclusion. Specific excluded ICH were epidural or subdural hematomas, significant intraventricular blood, surgical intervention planned, or those in which death appeared imminent. Treating clinicians could not be blinded to study arm allocation, but follow-up assessors and data analysis was masked. The primary outcome is was functional outcome on the modified Rankin Scale, analyzed via ordinal shift analysis.
The authors do not present the number of patients screened for potential enrollment during the study period, but, ultimately, 190 participants were included from 41 centers. The authors state patients were well-balanced on most demographics, although median ICH volumes were a little higher in the platelet-transfusion group, with 34% of patients having ICH >30mL versus only 21% in the standard-care group. There were four patients in the platelet-transfusion group who did not receive transfusion, and two in the standard-care that did.
In the end, outcomes were universally dismal. Only 15 patients in the entire study survived with minimal disability or better. The vast majority of patients were at least moderately disabled or dead at follow-up. And, while the confidence intervals for many of their comparisons cross unity, none of the trends favored platelet transfusion. Generally speaking, there were more deaths, fewer patients with minimal disability, and additional adverse events in the transfusion group.
I tend to feel this is a small enough cohort the heterogeneity between individual patients is enough to effect the overall results – including the apparent harms relating to platelet-transfusion. However, there is certainly no signal of benefit, and lacking a compelling indication to utilize a scarce resource, I believe this is enough to suggest this practice should be routinely avoided.
“Platelet transfusion versus standard care after acute stroke due to spontaneous cerebral haemorrhage associated with antiplatelet therapy (PATCH): a randomised, open-label, phase 3 trial”