Measurement of blood pressure during pregnancy: evaluation of the 'TriCUFF'.

Previous surveys have revealed that a major source of error in measuring blood pressure in pregnant women is failure to use a large cuff when necessary. We have tested the hypothesis that this problem could be overcome by using a single cuff containing automatically selected inflation bladders of appropriate size, the TriCUFF. We compared readings obtained with the TriCUFF with those obtained using standard adult or large (obese) cuffs in 51 pregnant women. Thirty nine had normal upper arm circumferences (< 34 cm) and 12 increased arm circumferences (> or = 34 cm). The TriCUFF overestimated standard cuff systolic and diastolic (phase IV) readings by 2 (0-4) mmHg (mean, 95% confidence limits) (p < 0.05). There was no difference between readings for women with large arms. Agreement between readings by both methods was acceptable for clinical practice in most cases. Use of the TriCUFF could significantly improve the accuracy of blood pressure recording in pregnant women.