Is needle electromyography safe in patients on anticoagulation or antiplatelet therapy?

Needle electromyography (EMG) is a valuable diagnostic tool in the evaluation of the PNS and yet the risk of complications with this procedure in patients on anticoagulant or antiplatelet medications is unknown. Guidelines recommend caution when performing needle EMG in patients with disturbances of hemostasis because of the risks of intramuscular hemorrhage or other bleeding. This commentary reviews a study by Lynch et al. that investigated the risk of hematoma formation following needle EMG of the tibialis anterior muscle in 158 patients on antiplatelet or anticoagulant medications. The authors used a standardized approach to the needle examination, followed by application of direct pressure to the insertion site after removal of the needle. Three hematomas were detected--two in patients on warfarin, and one in a patient taking clopidogrel. None of the patients had symptomatic bleeding. These results indicate that the risk of hematoma formation is low following needle EMG when direct pressure is applied after removal of the needle.