How accurate is inpatient blood pressure measurement?

Background: Accuracy of blood pressure (BP) measurement depends on quality technique, yet there are no existing guidelines for accurate measurement of inpatient BP. We assessed the performance of BP measurements in a major teaching hospital by comparison with consensus criteria. METHODS: Routine BP measurement methods were observed across 3 noncritical care wards (aged care, acute surgical, and hematology) at St George Hospital, Sydney, over a 3-week period. Aspects of BP measurement were compared for concordance with an ideal BP measurement technique, consisting of 10 consensus criteria, as determined by an expert panel. RESULTS: A total of 278 BP measurements were observed in 153 patients. Concordance with the consensus criteria was high for device calibration (92%), uncrossed legs (82%), using the correct cuff size (77%), and back support (75%). Concordance was moderate for the criteria of correctly positioned cuff on a bare arm (both 65%), and poor for the remaining criteria (seated position [26%], no talking [23%], cuff at heart height [15%], and taking at least 2 measurements [7%]). No observed measurement met all 10 of the consensus criteria for BP measurement quality. CONCLUSIONS: Our findings indicate considerable discordance between routine BP measurement and optimal technique (as determined by an expert panel) in an Australian hospital setting. The lowest concordance was observed for the 3 highest-ranked consensus criteria for accurate BP measurement. This variability may result in inaccurate and biased readings. Standardized, hospital-specific BP measurement guidelines and training are needed to improve BP measurement accuracy.