Patient satisfaction with the SpaceLabs 90207 ambulatory blood pressure monitor in pregnancy.

OBJECTIVE: The objective of this study was to evaluate the acceptability of the SpaceLabs 90207 ambulatory blood pressure monitor among pregnant women. METHODS: Patients participating in research projects involving ambulatory blood pressure monitoring (ABPM) in pregnancy (N = 110) were asked to complete a questionnaire relating to patient satisfaction on completion of the monitoring period. The first part of the questionnaire involved rating on a visual Likert scale (0-10) whether they found the monitor heavy, noisy, cumbersome, disturbing, or embarrassing to wear. The second part of the questionnaire addressed whether cuff inflation caused significant sleep disturbance or physical discomfort. OUTCOME MEASURES: The mean (SD) and range of the Likert scores are reported. The number of patients reporting sleep disturbance or physical discomfort was calculated. Logistic regression was used to examine which factors were significant predictors of discontinuing monitoring. RESULTS: The mean (SD) responses measured by the Liken scores were: finding the monitor heavy 3.2 (2.3); comfortable 4.8 (2.3); straightforward to use 8.8 (1.8); cumbersome 3.8 (2.3); disturbing 4.5 (2.7); noisy 1.6 (2.2); and embarrassing to wear 1.7 (2.1). Difficulty initiating sleep was reported by 28.8% of patients, and a further 56.3% reported difficulty maintaining sleep due to the monitor. Sleep disturbance was found to be the strongest predictor [r = 0.52; OR 1.68 (1.23, 2.27), p = 0.0009] for the 15% of patients discontinuing the monitoring. CONCLUSIONS: While pregnant women tolerate the noise, weight, inconvenience, and disturbance associated with ambulatory blood pressure monitoring (ABPM) well, sleep disturbance is a major cause of dissatisfaction and noncompliance. Future studies should evaluate critically the number of nocturnal blood pressure assessments required, and should allow for a withdrawal rate of approximately 15% when performing sample size calculations for ABPM studies in pregnancy.     

Diurnal blood pressure variation in the evaluation of early onset severe pre-eclampsia

OBJECTIVE: To study the association between diurnal variation in blood pressure, the mean daily blood pressure and various complications of pregnancy in patients presenting with severe pre-eclampsia before 34 weeks' gestation. STUDY DESIGN: Forty-four women presenting to a tertiary hospital in South Africa with severe pre-eclampsia between 28 and 34 weeks' gestation were managed expectantly for at least 8 days. We measured maternal blood pressure every 30 min with the pregnancy validated Spacelabs 90209 automated blood pressure monitor for 24h periods on alternative days. The mean 24-h diastolic blood pressure measurement, the mean diastolic blood pressure for daytime and nighttime, the day-night blood pressure difference and the night-day ratio were compared with the occurrence of abruptio placentae, gestational age at delivery, neonatal intensive care unit admission, birth weight, abnormal umbilical artery Doppler FVW and reason for delivery. RESULTS: One hundred and seventy-six 24-h studies were analyzed. The day-night blood pressure difference decreased with increasing mean diastolic blood pressure (r=-0.323, p<0.0001). A combination of normal mean diastolic blood pressure and normal day-night blood pressure difference was associated with increased gestational age and lower caesarean section rates. CONCLUSION: The combination of mean diastolic blood pressure and day-night blood pressure difference may be a supplementary measurement of disease severity in early onset severe pre-eclampsia and seems to be of prognostic value.     

Inflationary oscillometry provides accurate measurement of blood pressure in pre-eclampsia

Objective To evaluate the accuracy of the OMRON-MIT inflationary oscillometric device for blood pressure measurement in pregnancy and pre-eclampsia.
Design Prospective observational study, using validation methods recommended by the British Hypertension Society (BHS) and the Association for the Advancement of Medical Instrumentation (AAMI).
Settings Antenatal clinics and ward, Guy's Hospital, London.
Population Normotensive pregnant women and those diagnosed with pre-eclampsia according to the definition of the International Society for the Study of Hypertension in Pregnancy.
Methods Validation according to BHS protocol.
Main outcome measures Proportion of readings within 5, 10 and 15 mmHg (absolute differences) between the automated device and two trained, blinded observers, according to the BHS and AAMI criteria.
Results The OMRON-MIT achieved an overall BHS grade B for systolic and grade A for diastolic blood pressure measurement in both pregnancy and pre-eclampsia. The mean (SD) differences between the standard and the test device were −5 (7) mmHg for systolic and 2 (6) mmHg for diastolic blood pressure in pregnancy and −4 (6) mmHg for systolic and 2 (7) mmHg for diastolic blood pressure in pre-eclampsia. This device therefore fulfils the AAMI criteria.
Conclusion The OMRON-MIT is the only automated oscillometric device that has proven to be accurate for blood pressure measurement in pre-eclampsia according to the BHS protocol in pregnancy. Inflationary oscillometry may correct the error associated with oscillometric devices in pre-eclampsia.     

Accuracy of oscillometric blood pressure monitoring in pregnancy and pre-eclampsia

Objective To assess the accuracy of the Omron HEM 705 CP oscillometric device for the measurement of blood pressure in pregnancy and pre-eclampsia.
Setting Two teaching hospitals.
Participants Eighty-five pregnant women with a wide range of blood pressures, and 43 women with pre-eclampsia.
Methods Evaluation was carried out according to the British Hypertension Society protocol, incorporating criteria of the Association for the Advancement of Medical Instrumentation (AAMI).
Results Mean differences (device minus observer) for systolic blood pressure were −0.9 mmHg (SD 10) in normal pregnancy, and −2 mmHg (SD 10) in the women with pre-eclampsia. For diastolic blood pressure, Korotkoff phase V, the differences were −1.5 mmHg (SD 10), and −8 mmHg (SD 8) respectively; i.e. the device consistently under-read the diastolic blood pressure in pre-eclamptic women by a mean of 8 mmHg when compared with conventional sphygmomanometry. Korotkoff phase IV could not be accurately reproduced. According to the British Hypertension Society grading criteria, the device reached a 'B' grading in the 85 pregnant women. In pre-eclampsia only a 'C' grade was reached for systolic blood pressure, and 'D' grade for diastolic blood pressure. Accuracy criteria stipulated by the AAMI were not met in any situation.
Conclusion The Omron HEM 705 CP does not reach acceptable accuracy criteria for blood pressure measurement when compared with trained observers in women with pre-eclampsia, as judged by the British Hypertension Society Protocol. It also failed to meet the AAMI criteria, although the methodology stipulated by the AAMI may not be applicable to a pregnancy population.     

Haemoconcentration in severe pre-eclampsia

Summary. The last maternal haemoglobin (Hb) concentration before delivery was related to the perinatal outcome in 87 non-anaemic women suffering from severe pre-eclampsia. Abnormally high Hb concentrations were found in most women with evidence of placental dysfunction. An inverse correlation was found between the centile weight of the newborn and the maternal Hb. Significantly higher Hb levels were found in pregnancies complicated by fetal growth retardation and perinatal distress compared with those in pregnancies with good outcomes. Particularly high levels were found in pregnancies that ended in perinatal deaths. The hypothesis is put forward that raised haemoconcentration during severe pre-eclampsia causes increased maternal blood viscosity which predisposes to placental pathology and initiates a vicious circle.     

Automated blood pressure measurement as a predictor of proteinuric pre-eclampsia

Objectives To investigate the relation between antenatal clinic, obstetric day unit and 24-hour ambulatory blood pressure measurements and 24-hour proteinuria levels in hypertensive pregnancies.
Design An observational study.
Participants Forty-eight women presenting with new hypertension after 20 weeks of gestation.
Results The closest relation was found between ambulatory blood pressure measurements and 24-hour proteinuria levels. No significant relation was found between the conventional diastolic blood pressure threshold of 90 mmHg and 24-hour proteinuria levels.
Conclusions Ambulatory blood pressure measurement gives better information about disease status in pre-eclampsia as assessed by proteinuria than does conventional sphygmomanometry.     

Home monitoring of blood pressure in pregnancy at high risk of pre-eclampsia

The early detection of pre-eclampsia is a major challenge in obstetric care. We report a case where pre-eclampsia was detected by home blood pressure monitoring between routine antenatal visits. This novel management approach allows early diagnosis and optimises antenatal care in fulminating disease.     

Hemodynamic measurements with Swan-Ganz catheter in women with severe proteinuric gestational hypertension (pre-eclampsia)

Ten women with severe pre-eclampsia, i.e. a blood pressure greater than or equal to 150/110 mmHg or 140/90 mmHg and proteinuria greater than 3 g/24 h were, after initial antihypertensive treatment, centrally monitored with a pulmonary artery catheter (Swan-Ganz). All had been normotensive in early pregnancy. Mean age was 29 years (range 23-37). Mean gestational age upon admission was 29 weeks (range 23-36) and 7 of the women were nulliparous. Nine of the 10 patients had subjective symptoms, e.g. headache and/or epigastric pain. All were considered in need of intensive care. Two patients were found to have an abnormal coagulation and liver function. All patients had normal serum creatinine values despite proteinuria. Hypertension was treated with dihydralazine and/or labetalol. Volume substitution was carried out with plasma and albumin. The women could be divided into two groups: 5 patients where progress of the disease despite therapy led to delivery within 24 h, and 5 patients whose diastolic blood pressure could be stabilized around 100 mmHg after treatment and pregnancy could be prolonged by 5-13 days. Common for all patients was a hyperkinetic circulation with an increased cardiac output despite a variety of central pressures. Invasive monitoring of central pressures with a Swan-Ganz catheter demonstrated that the clinical status could be stabilized and the pregnancy prolonged in 5 of the 10 women with severe pre-eclampsia. The variety of the central hemodynamic values illustrates clearly that treatment has to be individualized regarding antihypertensive medication, fluids and diuretics.(ABSTRACT TRUNCATED AT 250 WORDS)     

Pharmacological management of severe pre-eclampsia

(Very) High blood pressure in pre-eclamptic women poses a serious risk of acute cerebrovascular complications in these women, necessitating the use of antihypertensive treatment in pre-eclampsia. In this review, the different antihypertensive drugs used in the management of pre-eclampsia are discussed with a focus on efficacy and maternal and neonatal safety. The characteristics of each drug are summarised, including placental transfer, and comparisons between antihypertensive drugs are shown, based on recent publications. Special emphasis is given on newer developments including treatment with ketanserin or nicardipine. Especially nicardipine seems to be a potent drug in the treatment of pre-eclampsia, but comparative trials are needed.     

Blood rheology in pre-eclampsia and intrauterine growth retardation: effects of blood pressure reduction with labetalol

Blood viscosity ( Contraves L S 30) and its determinants were measured in 23 patients with mild/moderate pre-eclampsia, 10 patients with intrauterine growth retardation and 22 control subjects, matched for age and gestation. Both abnormal groups had a significantly increased blood viscosity at high shear rate (94 s-1) associated with increased haematocrit. Fibrinogen levels were also increased, but there were no significant differences between groups in plasma viscosity, low shear viscosity (0.94 s-1) or red cell deformability, measured by a low-shear washed cell system of filtration through 5-micron pore diameter Nuclepore filters. In the pre-eclamptic group, measurements were repeated after 1-2 weeks in nine patients treated with labetalol (a combined alpha and beta adrenergic blocker) and in 10 patients treated with bed rest. Labetalol reduced blood pressure but no change in rheology was seen in either group. Control of blood pressure by labetalol does not adversely affect rheology, in contrast to diuretics which are known to cause haemoconcentration and increased blood viscosity.     

Autonomic nervous dysfunction in severe pre-eclampsia

We evaluated autonomic nervous function in 14 subjects with severe pre-eclampsia and 11 subjects with normal third-trimester pregnancies using standard cardiovascular tests, i.e. heart rate responses to deep breathing and standing up, and blood pressure response to standing up. Both of the heart rate responses were lower in subjects with severe pre-eclampsia than in the control group (P less than 0.01 and P less than 0.001, respectively). Four subjects with severe pre-eclampsia had postural hypotension, defined as a systolic blood pressure fall of at least 30 mmHg on standing. Our results show that severe pre-eclampsia may be associated with autonomic nervous dysfunction. The inability to regulate heart rate and blood pressure in response to postural alterations may compromise the placental and renal blood flow in certain conditions, emphasising the importance of bed rest in severe pre-eclampsia.