Methods of measurement.
Four points, I feel, have dominated the session devoted to the methods of measurement; First, we all seem to be convinced that ambulatory measurement of blood pressure shows great promise, not only in clinical trials of drugs but also in routine practice. Further development of the technique will almost certainly encourage more manufacturers to produce machines, which by the operation of market forces should lead to lower prices. However, we need to be critical with respect to instrument quality and to the rigour of validation according to the guidelines of hypertension societies, especially for particular populations such as elderly patients. Second, two methods of indirect measurement of blood pressure are now being employed, namely auscultation and oscillometry, which are likely to remain the most widely exploited ones with the current technology. They should not be regarded as competing methods because both have their role to play in the measurement of ambulatory blood pressure, with their own advantages and limits. A possible development would be intelligent machines using both techniques, which could switch between methods depending on the actual conditions of each measurement. Third, desirable features of the new machines would be: more comfortable recording conditions for the patient with a lighter, quieter device giving a faster reading and thus reducing the cuff inflation time; and assistance with interpretation, which I believe is compatible with current technology such as automatic determination of the position of the patient (upright or supine) using some form of sensor and quantification of the degree of activity of the patient, which clearly affects blood pressure. Fourth, it is also likely that future development will include devices capable of measuring blood pressure together with other parameters the variations of which according to blood pressure changes may be of great interest, such as electrocardiographic data, oxygen saturation and the QKD interval. For all these reasons, the near future will certainly see much progress in the ambulatory measurement of blood pressure.
Gosse
P
Hôpital Saint André, Bordeaux, France.