cause. It would be interesting to know how many of the perinatal deaths in the "anoxic" group in Cardiff corresponded to deaths of unknown cause in mature infants and to know the age, parity, height, and social class of the mothers. Higher induction and section rates in these groups most at risk might have resulted in better figures.Fedrick and Yudkin9 reported a reduction in the number of stillbirths in the Oxford area associated with a rising induction rate. The reduction was more apparent in induced than in noninduced births. As they pointed out themselves, however, when the induction rate is low only pregnancies at very great risk are included in an induced group, but as the induction rate rises, more and more relatively normal cases are induced. It is difficult, therefore, to draw firm conclusions about the benefits of induced labour from their method of analysing their data. Possibly the optimum induction rate will vary from area to area depending on the characteristics of the populations. By detailed analysis of our population and classification of the causes of our perinatal deaths, we were able to show where greatest improvement could be made, and it would be valuable to compare our results with those from other centres. Our present findings strongly suggest that increased use of induction of labour has contributed to a reduction in perinatal mortality.

No abstract

In addition to their effects on blood pressure, antihypertensive agents may produce additional effects on blood rheology and arterial compliance abnormalities which may play a role in target-organ damage. However, these effects may depend only on the specific pharmacological properties of certain antihypertensive agents, and may be partly unrelated to blood pressure lowering action. We compared the effects of nitrendipine 20 mg once daily to hydrochlorothiazide 25 mg once daily in 33 mildly to moderately hypertensive and otherwise healthy patients, in a double blind parallel group trial. Blood rheology (blood fibrinogen and protein concentrations, hematocrit, plasma viscosity and whole blood viscosity at shear rates 0.2 to 128 s-1, erythrocyte deformability and aggregation) and radial artery diameter and compliance (Nius I + Finapres) were measured at baseline and after 2 months of treatment. Both drugs produced similar blood pressure lowering. Blood viscosity increased for all shear rates in the hydrochlorothiazide group and decreased in the nitrendipine treated group. Erythrocyte deformability increased in the nitrendipine but not in the thiazide group. Radial artery diameter and compliance were not different between the two groups but there was a trend towards an increase in cross-sectional compliance in the hydrochlorothiazide group and towards a decrease in the nitrendipine group. Our data show that, in mildly hypertensive patients, blood pressure control by nitrendipine produced more favourable effects on relevant rheological variables than hydrochlorothiazide. Radial artery compliance changes tended to be altered also in opposite directions by the two agents. The significance and the clinical relevance of these effects may require further investigations.

Short-term fluctuations in blood pressure (BP) and heart rate (HR) were analysed in a group of twelve males with essential hypertension. Indirect finger BP was measured by a Finapres device. The effect of a 7-day administration of a cardioselective beta-adrenoceptor blocker, acebutolol (400 mg/day), was studied in a double-blind, randomized, placebo-controlled cross-over study. Compared with placebo, acebutolol caused a significant decrease in BP and HR. In addition, the standard deviation (SD) of BP and HR were reduced after acebutolol in the standing position. Spectral analysis of fluctuations in BP showed a reduction in the variability underlying the SD changes of BP and HR. This reduction predominated in the mid frequency (MF) region corresponding to Mayer waves. This effect was marked for HR since the MF component for standing HR after acebutolol was 46% the placebo level. The average reduction in MF component for standing Systolic BP (SBP) was 36%. No significant correlation was found between the Mayer wave reduction and the systolic, diastolic BP or HR lowering effect of acebutolol. No significant changes in the gain of the transfer function between MF SBP and HR fluctuations in the standing position were observed. The reduced MF component of HR and BP variability after acebutolol could be due to a peripheral cardiac and non-cardiac sympatholytic effect of chronic beta-adrenoceptor blockade.