[The meaning and implementation of clinical governance]

Under the 1999 Health Act a statutory duty of "quality" was given to National Health Service (NHS) organisations in the United Kingdom. This was matched by a comprehensive quality program. In this paper we look at the meaning of clinical governance as a mechanism for ensuring local delivery of high quality clinical care in the UK, the national structures which have been put in place to develop, reinforce and implement clinical governance and the role of the NHS Clinical Governance Support Team (CGST) in delivering clinical governance "on the ground". As part of the quality program, the CGST is working to enable national clinical governance policy to be translated into practice locally by supporting the development of better ways of working by individuals, clinical teams and health organisations to deliver a continuous, integrated approach to quality healthcare for patients.

Effect of concentration and biochemical assay on the accuracy of urine dipsticks in hypertensive pregnancies

OBJECTIVE

To assess how urine concentration and biochemical assay influence the assessment of proteinuria.

METHODS

This was a prospective study to assess the accuracy of detection and quantification of proteinuria within the day assessment unit and antenatal ward of a teaching hospital in Leicester, United Kingdom. We studied hypertensive pregnancies (of mixed parity) referred to day care assessment or attending the antenatal hypertension clinic after 20 completed weeks of gestation (n = 197). Aliquots of a well-mixed 24-h urine collection were tested by routine dipstick urinalysis and then assayed for protein using the Benzethonium Chloride and the Bradford assays (n = 197).

MAIN OUTCOME MEASURES

Total protein excretion in 24 h and protein concentration per liter of urine for both biochemical assays were compared to semiquantitative dipstick protein measurement.

RESULTS

The prevalence of proteinuria in the study group varied according to the method used for testing. Dipstick urinalysis recorded the lowest prevalence (16.2%) and the Benzethonium Chloride assay measuring total protein excretion in 24 h recorded the highest (70.1%). When the positive and negative predictive values for dipstick urinalysis were calculated, performance was found to be dependent on both the units of measurement compared and the type of assay used as the "gold standard." Positive predictive values ranged from 87.5% to 96.9% and negative predictive values ranged from 35.2% to 92.1%.

CONCLUSIONS

The prevalence of proteinuria in hypertensive pregnancies is dependent on the method used to detect it. The amount of protein assessed quantitatively is further dependent on the biochemical assay employed. However, regardless of the quantitative assessment, dipstick urinalysis has a significant false-negative rate. This first reporting of a variation in performance between dipstick urinalysis and two different biochemical assays in pregnancy may be explained in relation to protein assay specificity and the observed protein compositions of the samples on electrophoretic analysis. The significance of proteinuria should be considered in light of the method used to detect it, but, ultimately, it must be related to clinical outcome.

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.

Reviewing a service--discovering the unwritten rules

In our previous article we looked at the history of quality development and discussed how the implementation of clinical governance provides the opportunity to begin the cultural shift necessary to underpin quality in the modern NHS. This article begins an explanation of the model of quality improvement followed by delegates to the Clinical Governance Development Programme by looking at the service review process delegate teams undertake.

Clinical governance: its origins and its foundations

This article from the NHS Clinical Governance Support Team (NCGST) outlines the development of quality concerns since the NHS was founded in 1948. It traces the development of clinical governance as a means of achieving continuous quality improvement and describes what the implementation of clinical governance means for patients and professionals. It analyses features of the cultural shift necessary to underpin quality improvement initiatives and describes with practical examples the constituents of the culture necessary for successful clinical governance. Future articles in this series will address other issues around clinical governance and will explain the model being followed by delegates to the NCGST's Clinical Governance Development Programme as they implement clinical governance "on the ground".

Inpatient monitoring on an outpatient basis: managing hypertensive pregnancies in the community using automated technologies

Automated measurement of blood pressure and urinalysis is reviewed, and the strengths and weaknesses of these devices are compared with conventional techniques. The few early reports of such management strategies are reviewed with emphasis on the advantages of automated monitoring. The article concludes with a review of published pilot data in this field and places those findings in the context of recent recommendations for the development of obstetric care in the United Kingdom.

Lack of consistency in research papers over the definition of pre-eclampsia

The most common definition of pre-eclampsia involves hypertension and proteinuria. This has changed little in over a hundred years despite advances in understanding the underlying pathological process. However, a number of variations in definition exist, and this paper demonstrates a lack of consistency in research articles in defining pre-eclampsia. A quarter of papers omit description, and many authors choose their own interpretation of the standard classification. Editors and reviewers should ensure that papers include a clear description of the definition used and an adequate description of the population studied to allow meaningful interpretation of research findings.

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.

Can 24-hour ambulatory blood pressure measurement predict the development of hypertension in primigravidae?

OBJECTIVE

To assess the role of 24-hour ambulatory blood pressure measurement in the mid-second trimester as a predictive test for the development of hypertension in pregnancy.

DESIGN

Prospective intervention.

SETTING

The Rotunda Hospital, Dublin.

PARTICIPANTS

One thousand one hundred and two healthy primigravid women.

INTERVENTION

24-hour ambulatory blood pressure measurement at 18 to 24 weeks of gestation.

MAIN OUTCOME MEASURES

The development of pre-eclampsia or gestational hypertension.

RESULTS

A total of 1048 women had sufficient readings to be included in the final analysis. Of these, 23 (2.2%) developed pre-eclampsia, 64 (6.1%) developed gestational hypertension and 961 (91.7%) remained normotensive. Significantly higher ambulatory blood pressures were recorded in both the pre-eclamptic and gestational hypertensive group compared with the normotensive group. In addition, the gestational hypertensive group had significantly higher clinically measured blood pressure compared with the normotensive group. There were no differences between the pre-eclamptic and the gestational hypertensive group for any of the blood pressure parameters analysed. The best overall predictor for pre-eclampsia was 24-hour mean diastolic pressure which using a cutoff level of 71 mmHg gave a test with a sensitivity of only 22% and a positive predictive value of 15%.

CONCLUSION

Because the absolute differences are small and the overlap between the hypertensive and normotensive groups large, ambulatory blood pressure measurement, in a healthy primigravid population, between 18 and 24 weeks of gestation is not a useful predictor of hypertension.

Hypertension in pregnancy: which method of blood pressure measurement is most predictive of outcome?

OBJECTIVE

To determine the clinical effectiveness of blood pressure (BP) measurement using conventional sphygmomanometry in the antenatal clinic and obstetric day unit compared with automated BP monitoring at home.

METHODS

The study population consisted of 109 nulliparous white women with BPs of at least 140 or 90 mmHg at the antenatal clinic after 20 weeks' gestation, who underwent obstetric day unit and 24-hour automated BP monitoring on the same day. Automated measurement was obtained every half hour for 24 hours using a commercially available device that had been previously validated in pregnancy.

RESULTS

At the traditional BP cutoff point (140/90 mmHg), the relative risk for subsequent development of adverse obstetric outcome was greatest for automated BP measurement: The relationships between outcome and automated diastolic BP were all statistically significant: proteinuria (P = .034), preterm delivery (P < .001), birth weight below the tenth percentile (P = .001), admission to the special care neonatal unit (P = .001), and cesarean delivery (P = .007).

CONCLUSION

Automated BP measurement appears to improve the identification of patients who are at high risk of poor obstetric outcome. Automated BP measurement is worthy of further evaluation as an antenatal screening and diagnostic test.

Diurnal blood pressure difference in the assessment of preeclampsia

OBJECTIVE

To evaluate diurnal variation in blood pressure (BP) in normal gravidas and those with preeclampsia, using ambulatory BP monitoring.

METHODS

A cross-sectional comparative observational study was performed in three teaching hospital maternity units. Twenty-four normotensive and 24 preeclamptic women who were similar in age, weight, and mean duration of gestation (35 weeks) were studied. Diurnal variation and BP measurement were assessed using ambulatory BP monitors validated for use in pregnancy and for which normal reference ranges for pregnancy have been derived.

RESULTS

At night, the BP fall was less in preeclamptic women than in normotensive women. The day-night BP difference decreased as average BP rose (diastolic gradient = -0.54 [95% confidence interval (CI) -0.77 to -0.31], systolic gradient = -0.36 [95% CI -0.58 to -0.14], where gradient denotes a unit increase in BP leading to an increase or decrease in the day-night difference).

CONCLUSION

The decrease in day-night BP difference observed in preeclampsia is inversely related to average BP. This blunting of the day-night BP difference may be a useful adjunctive measure of disease severity in preeclampsia.

Lack of reproducibility in pregnancy of Korotkoff phase IV as measured by mercury sphygmomanometry

BACKGROUND

Since hypertensive disorders of pregnancy are common, blood pressure is frequently measured in all pregnant women. Many authorities recommend that Korotkoff phase IV (K4, muffling of sound) is taken as the diastolic identification point measured on mercury sphygmomanometry in pregnancy because of reports that phase V (K5, disappearance of sound) is at or near to zero cuff pressure in some pregnant women. We compared the identification and reproducibility of K4 and K5 by observers unaware of each other's results.

METHODS

In the first part of the study, two pairs of observers each took 340 measurements in 85 pregnant women. The second part of the study consisted of 1120 measurements in 80 pregnant and 80 non-pregnant women by five pairs of observers. Measurements were taken simultaneously by sphygmomanometry with a shared cuff and diaphragm; the observers were in separate booths.

FINDINGS

K5 was identified in all measurements by both observers and never approached zero. K4 was heard in only 52% of measurements; in 33% of cases it was heard by only one of the pair of observers, so the pair agreed on its detection in only 19% of readings. Visual analogue scores used to assess Korotkoff sound quality indicated that systolic blood pressure was perceived significantly more clearly than diastolic blood pressure (K4 or K5). Even when K4 was heard by both observers, agreement on its value was poor (78% within 5 mm Hg vs 86% for K5, p < 0.05). K4 was heard significantly less often in non-pregnant women (32% of measurements). There was also no consistency in the identification of K4 within individual women.

INTERPRETATION

K4 has little value in clinical management because it cannot be reproduced accurately. We recommend that K4 should be replaced by K5 as the measure of diastolic blood pressure in pregnancy.

Haemostatic, fibrinolytic and endothelial variables in normal pregnancies and pre-eclampsia

OBJECTIVE

To determine the behaviour of the coagulation variables antithrombin III (ATIII), protein C, thrombin/antithrombin III (TATIII); fibrinolytic activity, tissue plasminogen activator antigen (t-PA), plasminogen activator inhibitors (PAI) 1 and 2, and endothelial involvement by fibronectin assay in normal and pre-eclamptic pregnancies.

DESIGN

Longitudinal and cross-sectional observational study.

SETTING

Antenatal clinic and maternity hospital.

SUBJECTS

Thirty-six primigravid normotensive caucasian patients, four of whom subsequently developed pre-eclampsia, and 12 patients with established pre-eclampsia.

MAIN OUTCOME MEASURES

Plasma levels of PAI-1, PAI-2 and t-PA antigen were determined using an ELISA technique as were TATIII complex levels of fibronectin. ATIII and protein C plasma levels were assayed using chromogenic substrate techniques.

RESULTS

PAI-1 and PAI-2 antigen levels rose progressively throughout normal pregnancy. Among the established pre-eclamptic group compared with matched normal pregnancies, the PAI-2 antigen level was significantly lower (48.5 +/- 22.8 versus 183.5 +/- 37.4; P < 0.001), the PAI-1 antigen level was significantly higher (122 +/- 34.4 versus 79.2 +/- 19.7; P < 0.001), ATIII activity was significantly lower (87.8 +/- 27.1 versus 110.9 +/- 19.3; P < 0.001) and TATIII complex levels were significantly higher (16.9 +/- 6.4 versus 10.2 +/- 5.9; P < 0.001). Among the four initially normotensive patients who subsequently developed pre-eclampsia, fibronectin levels were significantly elevated from as early as nine weeks of gestation.

CONCLUSION

Significantly elevated levels of PAI-1 and fibronectin occurring early in pregnancies that subsequently develop pre-eclampsia suggest that these variables may have predictive values. PAI-2 would seem to be a marker of placental function in pre-eclampsia while increased t-PA and TATIII complex levels reflect the severity of the condition.

Indomethacin-induced maternal convulsion in the treatment of preterm labour

A caucasian 28-year-old woman at 25 weeks gestation with a diagnosis of preterm labour suffered a convulsion after the administration of indomethacin. Convulsions are described as an infrequent complication with this therapy in the non-pregnant population. No such convulsion has been described to date in pregnancy.

Twenty-four-hour ambulatory blood pressure measurement in a primigravid population

OBJECTIVE

To establish the profiles of 24-h non-invasive ambulatory blood pressure measurement (ABPM) during the trimesters of pregnancy and the puerperium in normotensive healthy primigravidae.

DESIGN

A prospective study in which 24-h ABPM was performed on five occasions in each subject: in the first trimester between 9 and 16 weeks' gestation; in the second trimester between 18 and 24 weeks; in the third trimester between 26 and 32 weeks and between 33 and 40 weeks; and finally at 6 weeks post partum.

METHOD

One hundred and six Caucasian primigravid women who were normotensive at their first booking visit were recruited consecutively from the antenatal clinic and had 24-h ABPM performed with the SpaceLabs 90207 ambulatory system.

RESULTS

Of the 106 women recruited, 98 completed 24-h ABPM on four of the five measurement occasions. Four women delivered prematurely before 33 weeks' gestation, thereby missing one ABPM measurement. Changes during pregnancy and the puerperium were assessed against the ABPM performed in the first trimester. There was no difference for daytime or night-time systolic blood pressure between 9 and 33 weeks, but it rose significantly from 33 to 40 weeks. At 6 weeks post partum, systolic blood pressure was not significantly different from the daytime pressure in the first-trimester ABPM but was raised significantly at night. Diastolic blood pressure decreased significantly between 18 and 24 weeks for both daytime and night-time. From 33 to 40 weeks it increased in parallel with systolic blood pressure, and at 6 weeks post partum it was raised significantly compared with first-trimester values for daytime and night-time. The nocturnal fall in blood pressure was preserved throughout pregnancy with a significant difference between daytime and night-time measurements present on all measurement occasions for systolic, diastolic and mean blood pressures and heart rate. There were significant differences between daytime ABPM and clinic blood pressure for both systolic and diastolic blood pressure up to 33 weeks. From 33 weeks until 6 weeks post partum there was no significant difference between daytime ambulatory and clinic blood pressures.

CONCLUSION

This study provides reference values for ABPM in healthy primigravidae with generally uncomplicated pregnancies.

Accelerated folate breakdown in pregnancy

During pregnancy there is an increased requirement for folate. We studied pregnant women to determine whether the increased requirement might be due to enhanced catabolism of the vitamin. Six normal pregnant women provided 24 h urine samples during each trimester and postpartum while taking a defined diet. The urines were assayed for the folate breakdown products p-amino-benzoylglutamate (pABGlu) and its acetylated derivative p-acetamidobenzoylglutamate (apBGlu) by high-pressure liquid chromatography. Mean concentration of excreted apABGlu rose significantly in the second trimester but returned to baseline postpartum. This increased rate of folate catabolism produces an extra demand for dietary folate of about 200-300 micrograms per day in pregnant women, a considerably greater value than recent recommendations.

Intrapartum asphyxia in term and post term infants

Many attempts have been made to identify infants at risk of suffering asphyxial brain damage. In a retrospective review of records at the Rotunda Hospital over a five year period all infants who died or suffered seizures, presumed secondary to asphyxia, were compared with the general hospital population. Out of 28,655 deliveries reviewed, there were 13 deaths in infants at or after term associated with perinatal asphyxia, and 32 surviving infants had asphyxial seizures. Seizures were regarded as asphyxial in origin if they occurred in the first forty eight hours of life and were associated with other clinical evidence of asphyxia. The incidence of abnormal presentations, assisted breech deliveries, instrumental deliveries and emergency caesarean sections was all increased in the asphyxial categories compared to the control population. Referral to the fetal assessment unit was associated with a seizure rate of 0.16/1000 live births compared with a rate of 1.4/1000 in the remaining non referred hospital population. Nineteen percent of the infants who seized subsequently developed cerebral palsy. It would appear from our data that referral to the fetal assessment unit and the consequent assignment to "high risk" status is associated with low risk in terms of asphyxial outcome.

Clinical application of ambulatory blood pressure measurement in pregnancy

Eclampsia and pre-eclampsia are the most important obstetric causes of maternal mortality in the Western world. The current definitions of hypertensive disorders in pregnancy rely on arbitrary blood pressure limits based on intermittent clinic readings which are subject to bias and error. Twenty-four-hour ambulatory blood pressure monitoring can overcome many of these deficiencies but has only recently been introduced into antenatal care. Five pregnancy studies using ambulatory blood pressure monitoring are currently underway in Birmingham, Glasgow, Grenoble, Oxford and Dublin. The results so far indicate that ambulatory blood pressure monitoring is an acceptable method of measuring blood pressure in pregnancy. It is also concluded that ambulatory blood pressure monitoring may have several roles in the future antenatal management of hypertension, including modification of existing classification systems, a clinical confirmatory role and a possible predictive role for pre-eclampsia.

Plasma exchange in the management of severe rhesus haemolytic disease

Over a ten year period from 1977 to 1987, 30 mothers with severe rhesus haemolytic disease and expected fetal loss were treated by plasma exchange using a blood cell separator. All patients had at least on previous stillborn or neonatal death due to haemolytic disease of the newborn. Of the 30 patients, 19 pregnant women were successfully treated. Overall, 53% (16 babies) survived intact. Three of the deaths were due to causes other than erythroblastosis foetalis.