Agreement between student paramedics when measuring blood pressure

Abstract

Introduction Blood pressure (BP) measurement is a core vital sign used by paramedics during patient examination. Throughout the out-of-hospital phase of the patient journey, several paramedics at multiple time-points may measure the BP of a single patient. An understanding of agreement in measurement of BP between paramedics may inform the reliability of serial vital signs and trends arising subsequently. The aims of this study were to assess agreement in BP when measured by student paramedics on healthy volunteers, and to validate teaching methods in an undergraduate paramedicine program. Methods A prospective observational design was used to investigate agreement between student paramedics. Pairs of students simultaneously auscultated BP using a dual-head stethoscope, resulting in 40 pairs of systolic and diastolic measurements. Differences in measurements were assessed using paired T-tests. Agreement was assessed using Bland Altman plot analysis and intra-class correlation (ICC). Results There were no significant differences between measurements for SBP (-1.1 mmHg, 95% CI -3.77–1.57; p=0.41) or DBP (1 mmHg, 95% CI -1.67–3.67; p=0.45). Regarding agreement, Bland Altman analysis showed a mean difference of 1.1 mmHg (95% limits of agreement -17.44–15.24) and 1 mmHg (95% limits of agreement -15.11–17.12) for SBP and DBP, respectively. ICC agreement was excellent for SBP (ICC 0.92; 95% CI 0.85–0.96) and good for DBP (ICC 0.82; 95% CI 0.65–0.90). Conclusion This study of student paramedic measurement of BP indicates there are high levels of agreement when measured concurrently by pairs of students, and validates the teaching methods used at the host university program.