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J Dormandy

Publications and source records attributed to J Dormandy.

12 recordsLinked to original sources
PubMed1991

[Correlation between the results of Doppler velocimetry with spectral analysis and the viscosity of cord blood].

The contribution of rheological factors to be impedance of blood flow in the umbilical artery as determined by continuous wave Doppler ultrasound was investigated. Of the 51 pregnancies recruited, six were complicated by pre-eclampsia, 10 by intrauterine growth retardation, 15 by both pre-eclampsia and fetal growth retardation, and there were 20 controls. A significant correlation was demonstrated between both plasma viscosity and gestational age and the resistance index used to characterize the Doppler waveform. Multiple regression analysis demonstrated that changes in plasma viscosity explained 55 p. cent of the variance seen in the resistance index and that this was statistically significant. This finding is, however, unlikely to be of clinical significance as whole blood viscosity had an insignificant effect on the impedance in the umbilical artery. We postulate that vascular factors such as the number and calibre of the placenta arterioles are a more important determinant of umbilical artery impedance.

Blood Flow Velocity↗
PubMed1991

Abnormal neutrophil adhesion in sickle cell anaemia and crisis: relationship to blood rheology.

Defects in neutrophil adhesion and migration may contribute to the susceptibility to infection seen in sickle cell anaemia (SCA). These dynamic defects may be influenced by abnormalities in blood rheology found in this disorder. A whole blood model was used to study neutrophil adhesion in SCA patients: neutrophil adhesion to protein coated glass was quantitated by measuring the rate of disappearance of neutrophils from heparinized whole blood circulating through a perfusion chamber. Twenty-three adult patients (Hb SS) were studied in asymptomatic steady state, of whom nine were also studied during pain crisis, both before and 4-7 d after conventional therapy. Red cell and granulocyte filterability and whole blood and plasma viscosity were also measured. The half-time for disappearance from the perfusion system (t1/2) of neutrophils from patients in the steady-state was 93.5 +/- 8.4 min, compared to 49.1 +/- 2.8 min in normal age-matched controls (P = 0.001). In crisis t1/2 was further prolonged to 170.0 +/- 16.1 min (P = 0.01 v. steady state). After therapy, t1/2 decreased to 57.0 +/- 4.5 min (P = 0.001 v. pre-therapy state and P = 0.009 v. steady state) and was comparable to Hb AA controls. These findings reveal a neutrophil adhesion defect in SCA which worsens in crisis but is corrected following supportive therapy. Red cell filterability (expressed as average resistance to flow and pore-clogging particles) and white cell filterability (expressed as pore-clogging particles) were also abnormal in SCA and were found to correlate with neutrophil adhesion. Plasma viscosity also correlated with adhesion t1/2. The defect appears to be related to abnormal blood flow properties in SCA but the rheological factors cannot fully explain either the steady-state defect or the marked changes in neutrophil adhesion during crisis.

Adult↗
PubMedDate not supplied

Use of the prostacyclin analogue iloprost in the treatment of patients with critical limb ischaemia.

Five large, placebo-controlled, randomised prospective multicentre trials have been completed in several European countries, including a total of 728 patients with critical limb ischaemia (CLI). 593 had ulceration or gangrene and it is these which will be analysed in detail. Only patients with CLI who were unsuitable for further reopening procedures were entered and approximately a third of the patients had already had attempts at surgical revascularisation or interventional radiology. The maximum tolerated dose up to 2 ng/kg/min was determined during the first three days and then continued as a six-hourly intravenous infusion every day for two to four weeks, depending on the study. Pooled results showed a significant overall 21% increase in ulcer healing rate due to iloprost (p less than 0.001) compared with placebo. The improvement was greater in the three studies when treatment was continued for four weeks. The very hard end point of a major amputation or death during a 3 to 6 month follow up was available in three of the studies. Analysis of these together demonstrated a significantly lower incidence of major amputations after iloprost treatment (p less than 0.05). Thus the existing weight of evidence from a large number of patients suggests that a course of intravenous iloprost is useful in the management of patients with CLI and trophic skin changes, who are unsuitable for reconstructive surgery or catheter procedures.

Amputation, Surgical↗