Neurologists in Melbourne have identified a strategy to shorten time to antithrombotic administration in ischaemic stroke – a target that they say is a neglected aspect of acute stroke care in Australia.
While national audits show that 64% of patients in Australia receive antithrombotics within the recommended 48 hours, that figure falls well below international guideline minimum thresholds of 85% and the 97% frequency achieved in other countries.
“The components of stroke unit care which have received most attention include swallowing assessment, fever and sugar management. Surprisingly, there has been less attention on timely administration of antiplatelet therapy,” according to clinicians from the Department of Neurology at Monash Health, who say Australian data on target rates are not of the ‘high standard’ set by North American hospitals.
Auditing data from their own hospital, the team looked at factors related to time to antithrombotic therapy in 525 patients admitted to the stroke unit at Monash Health over a 12-month period in 2015. Some 42 patients had TIA while 483 had ischaemic stroke.
A review of admission diagnoses, time to triage, imaging, information on dysphagia screen and nil by mouth (NBM) status, revealed that TIA patients received antithrombotics earlier than those with stroke – a finding that could be linked to the presence of dysphagia in patients with ischaemic stroke.
Noting a 38% lower dysphagia frequency screen among patients with TIA, investigators suggested the observation might be a factor contributing to the shorter time to antithrombotics in that group.
The hospital, like most others across Victoria, uses the Acute Screening of Swallow in Stroke or TIA (ASSIST) tool for dysphagia screening of patients. It’s a highly sensitive tool and the presence of facial weakness would result in a patient being deemed to have failed the dysphagia screen – an outcome that would affect when – and how – patients are administered anti clotting agents.
“In our institution, patients who have failed this screening test are required to be assessed by a qualified speech therapist. Due to this potential for delayed therapy, 16% of patients were given aspirin by rectal method; five of these patients were classified as having a minor stroke.”
Alternative routes
While various guidelines including NICE, have recommended the use of rectal administration of aspirin or via nasogastric tube in patients with dysphagia, lead investigator Dr Thanh Phan and colleagues say an alternative route not yet explored is the use of intravenous or chewable aspirin.
Perhaps offering a more comfortable approach than rectal administration, chewable aspirin can disperse in the mouth without water and and is more cost effective with the chewable medication costing just $0.15 per tablet compared to rectal aspirin at $5.30 and intravenous aspirin at $20.00 per dose.
Other antiplatelet agents (clopidogrel, combined aspirin and clopidogrel, or aspirin and dipyridamole), which can’t be given by rectal or intravenous route, may require administration via a nasogastric tube if appropriate, or else experience delay in therapy until dysphagia improves, they add.