Mar 12, 1988 - SIR,-Dr Gareth Williams and others (23 January, p 233) may underestimate the reliability of bio- thesiometry. They show wide variability ...
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who look after those in nursing or residential homes for the elderly. Typically patients will be admitted to such homes at times of crisis, when the availability of medical information may be critically important. There is an additional problem when people are not certain that they will settle in a particular home and prefer to register temporarily with a new doctor at first. When they register permanently the transfer of records is delayed by the time spent as a temporarily registered patient. Meanwhile hospital reports and discharge summaries continue to be sent to the previous doctor. I care for 21 patients in a nearby nursing home. One was previously registered with my practice, one is temporarily registered (two months), and I am waiting for the records offive (mean 4 2 months so far). For the remainder, who are permanently registered with me, there was a mean interval between registration and receipt of records of 5 1 months (range 2-8 months) with an additional temporary registration period in half of them of 3 7 months. Thus eight months or more can be spent caring for an elderly and often ill patient with no knowledge of his or her medical past. This is despite excellent liaison with the local family practitioner committee. I issue a questionnaire to all new patients, but the information gained is often vague and unhelpful. One patient mentioned problems with her neck and her blood, but not until her notes finally arrived did I appreciate her multiple myeloma. The last note by her previous general practitioner read, "Admit for terminal care." What can be done about this heroic but dangerous business of treating patients blindfold? The idea of a summary card held by the patient is attractive but probably impractical. Who should have one? When does one become elderly? Why just the elderly anyway? If all patients have one why do they not simply transfer the entire record? While we wait for electronic "credit cards" containing medical information in a decipherable but secure form a simple solution suggests itself. When it is imperative to know about a patient's history a telephone call to the previous practitioner (why are doctors' telephone numbers not on medical cards?) could easily result in the summary card from the patient's notes or at worst a brief resume of the history being sent directly to the new doctor. This would involve a minimum of time and effort but would at least provide some peace of mind to the legions of blindfolded doctors.
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classes and those with less severe illness. This is "the inverse care law" squared. In this scenario severe psychotic illness would inevitably be neglected in favour of the "walking worried." Furthermore, history teaches us of the risk of an expanded private psychiatric sector bringing with it a burgeoning of dubious and unsupervised therapies. Because of the particular vulnerability of the mentally ill and their families there seems to be an unanswerable case for a divorce between treatment and personal profit. A further and larger objection lies in the main thrust of psychiatric intervention today. This is at the community level and demands the participation of experienced consultants in assessing patients, supporting their clinical teams, liaising with general practitioners (who are increasingly asked to carry psychiatric responsibilities beyond their formal training), and coping with the complexities of the Mental Health Act 1983. Nor should one forget teaching, research, planning of services, and defending services against the deprivations of budgetary cuts. Even the most ambivalent of psychiatrists is not yet capable of being in two places at the same time. A growing proportion of the working week spent in private clinics must reduce a consultant's availability on NHS wards and risk a decline in the clinical standards on such wards. We are not enthusiasts for the expansion of private practice in any specialty. The fairness, efficiency, and public acceptance of a properly financed National Health Service seems self evidently preferable. A return to market place psychiatry could be envisaged only by those not engaged in a clinical commitment to society's most underpriviliged victims, the mentally ill. Hackney Hospital, London E9 6BE
London E14
2 Walkinshaw SA, Cordiner JW, Clements JB, Mcnab JCM. Prognosis of women with human papilloma virus DNA in normal tissue distal to invasive cervical and vulval cancer. Lancet 1987;i:563. 3 Murdoch JB, Cordiner JW, Mcnab JCM. Relevance of HPV-16 to laser therapy for cervical lesions. Lancet 1987;u: 1433.
Variability in biothesiometry: an error of technique?
SIR,-Dr Gareth Williams and others (23 January, p 233) may underestimate the reliability of biothesiometry. They show wide variability between both contralateral sites and ipsilateral sites in 25% of non-diabetic and 24% of diabetic patients. It would be interesting to see the variability and scatter for the first readings at each site because, as in many other forms of sensory testing, the "fatigue" of the patient's sensorium is an important factor which may have clouded their results. Dr Williams and his colleagues discard the first 12 readings (three at each site) and then proceed to an additional two cycles of three measurements at each site-another 24. After 36 measurements it is not surprising that such variability is shown. My own practice is to use one measurement of threshold starting from zero volts at each site, after an initial reference point-remote from the test sites-for example, clavicles or sternum-to familiarise the patient with the sensation and its initial perception. A comparison of standard deviations with this technique and with the multiple tests used by the authors might prove the point. Biothesiometry remains a valuable way of quantifying threshold, but neurologists have long been familiar with the dangers of using a single sensory modality as a "screen" for neuropathies, T H TURNER since impairment may result from root or posterior column lesions. It is a useful way of monitoring DAVID WIDGERY change. J M S PEARCE Department of Neurology, Hull Royal Infirmary, Hull HU3 2JZ
Viral infection, human papillomavirus DNA, and cervical neoplasia
SIR,-I was surprised that Dr J B Murdoch and others (6 February, p 381) infer from their data a good correlation between histological or cytological diagnosis of wart virus infection and the presence of human papillomavirus deoxyribonucleic acid (DNA) sequences. J K BYNOE Of 34 samples taken from women with either histological or cytological evidence of wart virus Medical Centre, infection, 10 had no human papillomavirus DNA, Sherburn in Elmet, North Yorkshire LS25 6ED whereas nine of 20 normal samples did have such DNA. That the correlation between histological or cytological diagnosis and the results of DNA hybridisation was better when the samples were taken from colposcopically abnormal areas reflects Psychiatry: private and public provision mainly on the correlation between colposcopic and SIR,-Dr Greg Wilkinson (9 January, p 79) has histological abnormalities. The increasing frequency with which human failed to appreciate the implications of his own analysis. This may explain the bland tone of his papillomavirus 16 DNA is found in normal tissues homilies on the "mix" between NHS and private must surely suggest that the presence of human psychiatric care, which he seems to believe can be papillomavirus 16 DNA does not indicate a high satisfactorily resolved "by market forces and risk of subsequent malignancy.'"3 Indeed, the data from the matched internal controls in this Glasgow empirical means." He is doubtless correct in stating that "people study suggest that the relation between human with mental illness descend down the social scale," papillomavirus 16 infection and cervical maligthat insurance risks are so high that only the well nancy is association rather than causation. off can afford to insure for genuinely compreW P SOUTTER hensive psychiatric treatment, and that private of Obstetrics and Gynaecology, psychiatry is concentrated on "the outpatient Institute Hammersmith Hospital, treatment of patients with neurosis." A transfer of London W12 OHS consultant commitment towards private practice MF, Meanwell CA, Maitland NJ, et al. Human papilloma in psychological medicine must, therefore, mean a 1 Coxvirus type 16 homologous DNA in normal human ecotcervix. shift of medical effort towards the higher social Lancet 1986;ii: 157-8.
AUTHORS' REPLY,-We share Dr Pearce's concern about the need to strike a compromise between familiarity and "fatigue." We tried to develop a protocol for measuring vibration perception threshold which would allow the subjects to become fully accustomed to an unfamiliar stimulus without becoming bored and losing interest. We perfc-med vibration perception threshold measurements in groups of three at each of the four sites in rotation, with a total of nine determinations at each site. Although this is a relatively large number of observations, the whole procedure took only four to six minutes and would be much less vulnerable to boredom and distraction than the three hour testing procedures used at some centres. ' We do not think that fatigue was an important contributory factor to the wide variability in vibration perception threshold among different sites, as the values at any given site were confined to a narrow range which showed no tendency to increase as more readings were taken. At the right big toe, for example, the first and last readings differed by >5 voltage units in only six of the 64 non-diabetic and 10 of the 110 diabetic subjects, and in each of these cases the last six values all fell within a range of five units. This does not suggest increasing variability, which would be expected with fatigue or failing concentration; indeed, it highlights the need for several estimations as the first may be unrepresentative. In most cases the final stable value was lower than the first, presumably because some time was necessary to "tune in" to the stimulus, whereas those subjects reporting a lower
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initial threshold may have anticipated perception. These findings agree with those of Fagius and Wahren, who concluded that the consistency of readings at a given site improves progressively with an increasing number of determinations (up to 10 in their study).2 We agree entirely with Dr Pearce that biothesiometry should not be used in isolation to screen for neuropathy. We feel, however, that its use in monitoring change must be cautious in view of the extremely wide day to day variability at a given site which has been convincingly shown by the careful studies of Fagius and Wahren.2 These authors have calculated from their confidence intervals that only changes of the order of 50% from the initial value are likely to be significant. This margin of error is several times larger than the changes reported in many longitudinal studies on the natural course or response to treatment of diabetic peripheral neuropathy.
GARETH WILLIAMS JASWINDER S GILL VIc ABER HUGH M MATHER Department of Medicine, Royal Postgraduate Medical School, Hammersmith Hospital, London W12 OHS I Dyck PJ, Zimmerman IR, O'Brien PC, et al. Introduction of automated systems to evaluate touch-pressure, vibration and thermal cutaneous sensation in man. Ann Neurol 1987;5:502-10. 2 Fagius J, Wahren LK. Variability of sensory threshold determinations in clinical use. J Neurol Sci 1981;51:11-27.
Anaesthetic services in obstetrics SIR,-Dr G Young believes that the Association of Anaesthetists has made unbalanced decisions about small and isolated obstetric units (6 February, p 431). Of the 524 obstetric units in the United Kingdom, 222 have an annual delivery rate of less than 500 mothers. After a call from an isolated unit there is a delay until the anaesthetist arrives. There is usually a lack of fully trained assistance and limited equipment. Early transfer is preferable. This also prevents reduced cover for mothers in the base hospital while the anaesthetist is away. Although the selection process in Penrith is working, it is imperfect, since "1 7% of women in Penrith need an anaesthetist" and "the perinatal mortality averages 4-7 per 1000 births and this includes those transferred in labour." These perinatal deaths, presumably in healthy mature pregnancies, also have implications for neonatal services. The Association of Anaesthetists of Great Britain and Ireland and the Association of Obstetric Anaesthetists have recommended that each district should consider withdrawing anaesthetic services where there are infrequent demands. This would provide more complete cover for higher risk pregnancies. Mothers should be given information about the service, including any restrictions on the options for pain relief. Each mother can then choose whether she wishes to have her baby close to home or travel to a unit with full facilities for the four or five days in her lifetime which she will spend in the obstetric unit to have her average two children. Recent surveys suggest that at least 40% of mothers would prefer to travel to the facilities. Our recommendations are aimed at providing safer practice with limited resources, ensuring that each mother has the facts to make the choice between safer anaesthetic service or convenience. Department of Anaesthetics, University Hospital of Wales, Cardiff CF4 4XW
Chronic fetal hypoxia in diabetic pregnancy SIR,-Mr R J Bradley and others (9 January, p 94) selected a patient at particularly high risk of fetal complications. It would be interesting to know why this patient requested cordocentesis at 23 weeks for fetal karyotyping. Was there a high suspicion of a fetal abnormality? The patient allegedly had "good control of her diabetes" yet her glycosylated haemoglobin concentration was persistently above the normal range for pregnancy. The definition of "normal" cord blood pH and oxygen tension should have been based on data from uncomplicated diabetic pregnancies rather than a non-diabetic population. The second cordocentesis suggested fetal hypoxia without acidosis. This is unusual and it would be interesting to know if the cord blood lactate concentration was normal or not. The authors comment that ultrasonic assessments of fetal growth failed to identify that the fetus was small for gestational age and therefore at risk of hypoxia. Infants of diabetic mothers tend to be larger than the normal population and macrosomia may occur even if diabetic control is optimal. It would have been more appropriate to plot fetal growth on centile charts for diabetic pregnancies. The authors suggest that Doppler studies and cordocentesis may allow early detection of fetal hypoxia, but their patient was delivered after developing an abnormal fetal heart rate pattern, which is a "traditional" test of fetal wellbeing. It is difficult to appreciate from this case how Doppler studies and cordocentesis improved fetal prognosis by early detection of hypoxia since by the time the fetus was delivered it was both acidotic and hypoxic. FIONA M FAIRLIE J J WALKER A M MATHERS ALAN D CAMERON Glasgow Royal Maternity Hospital, Glasgow G4 ONA
AUTHORS' REPLY,-The case we described did not seem initially to be one in which the fetus was particularly at risk. Although the glycosylated haemoglobin concentration was raised, the results of monitoring the mother's blood glucose concentrations were satisfactory and she had no evidence of diabetic vasculopathy. The only cause for anxiety came when the Doppler studies carried out routinely at 23 weeks were abnormal. Cordocentesis would not have been performed at this time but for the fact that she had already requested fetal karyotyping to complement the detailed fetal anomaly scan she had already had. Some diabetic women who are aware of the risk of fetal abnormality wish to be reassured that their fetus is chromosomally as well as structurally normal. The traditional tests of fetal wellbeing failed to identify this pregnancy as being at high risk, and without the blood flow studies the case would have been managed on an outpatient basis without cardiotocography and the deterioration in the fetal condition would have gone unnoticed. The rate of diffusion of carbon dioxide and hydrogen ions across the placenta is much faster than that of oxygen, explaining the well recognised phenomenon of fetal hypoxia without acidosis. As the degree of uteroplacental insufficiency worsens acidosis ensues. Although the umbilical venous lactate concentration was 195 mmol/l (normal 0-55-1-95) at the first cordocentesis, it rose to 2-4 MICHAEL ROSEN mmol/l (normal range of 0-65-2 05) at the second. It is customary in the management of high risk pregnancies to compare the measures of fetal wellbeing with those in a normal pregnancy. We
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agree, however, that if the fetal growth had been plotted on our diabetic fetal growth chart the fetus would have appeared to be mildly growth retarded. The extent of the growth retardation even then would not have prompted admission to hospital for intensive monitoring, and the deterioration in the fetal condition would have gone unnoticed. The growth pattern of the growth retarded diabetic fetus is difficult to interpret in view of the conflicting effects of the two conditions. Recent work in our unit suggests that all babies are "growth promoted" to some degree by maternal diabetes. We do not claim that blood flow studies are the answer to the monitoring of fetal wellbeing in diabetic pregnancy, and, like Dr Tyrell (6 January, p 428), we have recently had a case of late intrauterine fetal death in a diabetic pregnancy three days after normal blood flow studies. In the case we described, however, the blood flow studies were of crucial importance in identifying a fetus at risk. Until the place of blood flow studies in diabetic pregnancy has been elucidated they will continue to form an integral part of our monitoring of the fetal condition. R J BRADLEY J M BRUDENELL K H NICOLAIDES Department of Obstetrics and Gynaecology, King's College Hospital, London SE5 8RX
SIR,-Mr R J Bradley and others (9 January, p 94) discuss the benefits of cordocentesis; however, this is not widely practised in the third trimester and we recommend caution in relying too much on Doppler studies of blood flow in the management of diabetic pregnancy. We have found Doppler studies to be highly predictive of antenatal fetal compromise in 450 non-diabetic high risk pregnancies, but the same has not been true in the 65 diabetic pregnancies we have studied. This is illustrated by the following cases. A 24 year old primigravida with severe retinopathy, nephropathy, and hypertension controlled with atenolol and then labetolol had Doppler flow studies at 26 weeks' gestation. The umbilical artery showed absent end diastolic flow. The studies were repeated many times over the next six weeks and end diastolic flow was always absent. Ultrasound examination showed satisfactory growth, and other indices of fetal wellbeing remained satisfactory, although her hypertension became slightly less well controlled and her proteinuria increased to 6 g in 24 hours. At 31 weeks she had an acute inferior myocardial infarction and was stabilised in the coronary care unit. Because of her gradually deteriorating condition a caesarean section was performed at 32 weeks' gestation with intensive cardiovascular monitoring. The baby boy weighed 1800 g and was in good condition. He required ventilation for the respiratory distress syndrome but made good progress, and he and his mother are now well. A 31 year old parous patient was transferred from another hospital at about 32 weeks' gestation. She weighed 121 kg and her diabetes had been very poorly controlled. She had massive hydramnios with one pool of liquor measuring 16 x 16 cm, and a huge fat line was seen on ultrasound examination. Despite stabilisation of her plasma glucose concentration fetal movements were absent and there were only very short episodes of fetal breathing. Cardiotocography was non-reactive over three hours with reduced variability of the fetal heart rate. Umbilical artery Doppler studies showed a resistance index of 0-67, which is well within our normal range. At caesarean section that day the baby girl weighed 3050 g and was asphyxiated with Apgar scores of two and six at one and five minutes
