P042: Pilot study for the inter-arm blood pressure systematic measurement during the diagnosis of transient ischemic attack in the emergency department

Abstract

Introduction: Our principal aim was to document the feasibility of the systematic measurement of the inter-arm blood pressure difference (IABPD) during an episode of transient ischemic attack (TIA) or mild stroke diagnosed in the Emergency Department (ED). As secondary goal was to compare the systolic blood pressure (BP) at triage with the systolic BPs measured during the IABPD. Methods: This is a single center pilot study. Patients presenting in the ED for a diagnosis of TIA were recruited. Once patient has been triaged and diagnosed of TIA, a research assistant made sure that the patient lay on a stretcher for at least 5 minutes. Two automated sphygmomanometers were applied, on each arm. No specific device or device calibration were required. Three consecutive simultaneous BP readings were performed, inverting cuffs arm to arm between each reading. Only the last two set of readings were used to calculate the mean IABPD. This method enables to minimize the error coming from the potential sphygmomanometers’ inaccuracies. Results: 32 patients were recruited from June to September 2017 and all had a successful IABPD measurement. Four patients had an IABPD >10 mmHg, varying from 1.5 to 13 mmHg when the left arm was higher and from 1 to 61 mmHg when the right arm was higher. Of the 22 patients where the triage BP arm side selection was recorded, only 11 were congruent with the arm presenting the highest BP during the IABPD measurement. Selecting of the arm with the highest BP value may better reflect cerebrovascular risk exposition. The mean systolic BP at triage was 159.3 mmHg (95%CI: 144.9-173.7) compared to144.8 mmHg (95%CI: 132.9-156.7) if the arm with the highest value during the IABPD measurement is selected and 142.4 mmHg (95%CI: 130.8-154.0) if the same arm as triage is selected. The p-value for these differences were 0.003 and 0.001 respectively. The patient which presented the IABPD of 61 mmHg, had a stroke 3 days after its ED visit which subsequently led to her death 10 days later. Conclusion: Our results show that the systematic IABPD measurement using a pragmatic approach in the ED is feasible and is ready to investigate its use in the context of a new TIA or mild stroke. This information may contribute to a better discrimination of the short-term risk of stroke and may help to diagnose acute aortic dissection, monitor more accurately BP during hyperacute stroke or estimate intracerebral hemorrhage risk if systemic thrombolysis is considered.