Objectives: To determine the accuracy of sphygmomanometers (SPHYGs) from a metropolitan EMS system and quantitate the mis-triage of adult blunt trauma patients based on erroneous systolic blood pressure (SBP) readings.

Methods-A: A cross-sectional, convenient sample of 150 SPHYGs was checked for accuracy using industry standards. Mean high and low deviations were calculated at 90 mmHg.

Methods-B: Retrospectively, a frequency distribution of the initial SBPs of all blunt trauma patients, age ≥21, seen in 1994 was plotted to characterize our study population. The numbers of patients potentially over- or under-triaged were identified when their reported SBP was corrected for using the mean high and low deviation plus 2 SDs.

Results-A: Overall, 25.3% of the SPHYGs were inaccurate. At 90 mmHg, 28.0% (42/150) were inaccurate with 16.7% (7/42) high by 4.6±1.5 mmHg and 81.0% (34/42) low by 6.2±4.2 mmHg; one was inoperable.

Results-B: 1,005 adult blunt trauma patients were evaluated; 61 were eliminated: 35 had initial SBPs of 0 mmHg and 26 had no SBP recorded (n = 944). The mean initial SBP was 138 ±30mmHg, and 3.8% (36/944) of the patients had SBPs <90 mmHg. Potentially, 2.0% (19/944) of the patients were undertriaged (initial erroneously high SBP reading 90–98 mmHg) and 2.5% (24/944) over-triaged (initial erroneously low SBP reading 74–90 mmHg).