DO DIFFERENT PULSE AND HEART RATE MEASUREMENT METHODS RENDER THE SAME RESULTS?

Atrium

Objective. This study was conducted to determine if significant differences exist among four different rate measurement devices and four different rate measurement time periods when each device was used in combination with each time period at rest. Background. Clinically, the words “heart rate” (electrical event) and “pulse rate” (mechanical event) are often used interchangeably. However, some contractions of the left ventricle fail to produce peripheral pulse waves and occasionally manually palpated rates are estimated using abbreviated (10 s, 15 s, 30 s) counts; either scenario raises possible documentation consistency and patient safety concerns. Methods. Thirty-two (9 males, 24.7±2.1yrs; 23 females, 24.1±2.1yrs) physical therapy students were randomly selected to participate in the study. Following acquisition of informed consent, subjects were positioned supine while the heart and pulse rates were obtained simultaneously at 10, 15, 30, and 60 s from four sources: radio telemetry ECG (RT ECG); hand held ECG (HH ECG); pulse oximeter (PO) and, manual palpation of the radial artery (MP). Results. Data analysis revealed significant overall differences (p ~ 0) in the pulse rate measurements among the devices and among the time periods. Within-subject contrasts revealed that all rate measurements were significantly different (p ~ 0) for all the devices when compared to RT ECG with all rate measurements significantly different (p ~ 0) from 60 s as well. Within-subjects contrasts also indicated significant interaction terms between the device and time-period. The following interaction terms were significant (p < 0.03): RT ECG v HH ECG at time periods 10 s v 60 s and 30 s v 60 s; RT ECG v MP at time periods 10 s v 60 s and 15 s v 60 s. Effect size analysis revealed medium to high effect sizes among device contrasts and medium effect sizes for time-period contrasts Conclusion. We conclude, that although rate differences between methods were small, they were non-the-less significant and appear worthy of clinical consideration - especially for the elderly and for those with cardiac dysrhythmias. Of particular interest was the inconsistency seen between most all methods, whether pulse or heart rate. This appears to support the notion that rates should be obtained from the same device whenever possible to minimize variations due to method. The rate differences observed between ECG methods cannot be explained. However, 60 s MP rates calculated from abbreviated 10 s and 15 s counts clearly lacked precision since they are estimates only. Grants. N/A