Intra-arterial versus oscillometric blood pressure measurements in women with severe peripartum hypertension undergoing urgent treatment with nicardipine: An observational study.

OBJECTIVES

The aim of this study was to compare radial arterial catheter-derived pressure with oscillometric blood pressure in women with severe peripartum hypertension undergoing urgent treatment with intravenous nicardipine at a maternal intensive care unit.

STUDY DESIGN

We obtained patients' paired values of systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean arterial pressure (MAP). All of the measurements were divided into four groups based on the levels of SBP and MAP measured using the oscillometric method.

MAIN OUTCOME MEASURES

We assessed agreements of the paired values using the Bland-Altman method. The clinical relevance of differences between the two methods was assessed by error grid analysis.

RESULTS

A total of 337 paired SBP and DBP values and 305 paired MAP values were obtained for 89 patients. The values of intra-arterial SBP were higher than those of oscillometric SBP. The values of intra-arterial MAP were higher than those of oscillometric MAP except for the women with MAP ≥ 125 mm Hg. Bland - Altman analysis showed acceptable agreement for DBP and MAP measured by intra-arterial method and oscillometric method. Error grid analysis showed the proportions of measurements in risk zones A to E were 83.22%, 16.46%, 0.32%, 0%, and 0% for SBP, and 97.81%, 2.19%, 0%, 0%, and 0% for MAP, respectively.

CONCLUSION

Intra-arterial MAP can be used reliably to monitor the effect of intravenous nicardipine for treating severe hypertension. Intra-arterial SBP may trigger moderate-risk treatment decisions in the women with oscillometric SBP ≤ 160 mm Hg.