Comparison of the Use of Conventional and Prewired Electrodes for Electrocardiography in an Emergency Setting: The Spaghetti Study

Abstract

We compare the quality of ECG recordings obtained with conventional and prewired electrodes in an emergency setting. This was a prospective, randomized, open comparison study in an emergency medical services setting. Participants were patients undergoing ECG between April and May 2007 (n=105). Two 12-lead ECG recordings were made in random order with conventional and prewired electrodes. Artifacts, ie, signal noise (>0.4 seconds of recording affected) and baseline instability (>1-mV variation), were analyzed and scored by 3 blinded reviewers. Results were expressed as number of affected leads, score/lead (0 to 3 scale for signal noise; 0 to 4 scale for baseline instability), and number of leads that were totally artifact free. Time to make recordings was measured. Recordings were nearly as easy and took 20% less time with prewired than with conventional electrodes (118 [interquartile ratio (IQR) 90 to 150] versus 144 [IQR 120 to 182]). With prewired electrodes, fewer leads were affected by noise (1 [IQR 0 to 3] versus 3 [IQR 0 to 6]) and baseline instability (0 [IQR 0 to 2] versus 2 [IQR 0 to 4]). The mean score/lead was lower for both noise (1 [IQR 0 to 3] versus 3 [IQR 0 to 8]) and instability (0 [IQR 0 to 2] versus 2 [IQR 0 to 5]); the number of artifact-free leads was greater (38 [36%] versus 19 [18%]). There was no significant difference between electrode types in the prevalence of P-wave and QRS complex abnormalities. Recordings with prewired electrodes took significantly less time. Signal noise and baseline instability were significantly reduced. The time saved was not at the expense of the quality of the recording.