482
Anitschkow, N, and Chalatow, S, Zentralblatt fur allgemeine Pathologie und pathologische Anatomie, 1913, 24, 1. Finlayson, R,J_ournal of Zoology, 1965, 147, 239. 8 Adams, C W M, Bayliss, 0 B, and Turner, D R, 7ournal of Pathology, 1975, 116, 225. 9 Wilens, S L, American Journal of Pathology, 1947, 23, 793. 10 Geer, J C, and McGill, H C, in Atherosclerotic Vascular Disease, eds A N Brest and J H Moyer. London, Butterworths, 1967. p. 8. 1 Blankenhorn, D, in Proceedings of International Workshop-Conference on Atherosclerosis, London, Ontario. To be published 1976. 6
7
Crowded clinics Throughout Africa may be found crowded outpatient clinics where 200 or more patients have to be seen in a morning by one health worker. The combination of the large burden of ill health in the population, their increasing faith in the efficacy of western-type medical treatment, and free or cheap health care makes the demand for primary care out of all proportion to the provision of services. Furthermore, commercial pharmacies do not exist outside the major cities, and lack of knowledge about disease inhibits the practice of self-care for minor illnesses. It follows that many of the outpatients have minor ailments which do not require the attention of skilled health workers. Nevertheless, when there is less than three minutes to spend per patient, to recognise those needing attention from among the crowds is itself a skilled task not normally taught. To help improve diagnostic skills whenever many patients must be seen in a short time Essex has developed a method using problem-orientated flow charts,' and this has proved effective in Tanzania. The presenting symptom is taken as a starting point, and the health worker is then guided through a series of pertinent questions and examinations. The scheme also gives some excellent guidance on community diagnoses-a fundamental prerequisite for the diagnosis of individual patients in a busy clinic. How many health workers, for example, at health centres or dispensaries know how much tuberculosis they ought to be diagnosing? Essex's book is intended primarily for use by medical auxiliaries (oedema is delightfully described, in true medical tradition, in terms of a ripe, pawpaw), but the foreword suggests that doctors, too, might find the charts useful for outpatient diagnosis when time is a major constraint. The method is a radical departure from the conventional methods of history taking and diagnosis usually taught in the relaxed atmosphere of a hospital ward, but Essex emphasises that the technique should only be used by senior students who have already been taught "properly." That may be an arguable proposition, but undoubtedly problem-orientated flow charts, modified to lower the thresholds for referral, could prove invaluable in teaching basic auxiliaries, such as the part-time village health worker so much in vogue at present. Two questions arise. Firstly, how practicable is the method for routine use in a busy polyclinic? Unfortunately Essex's evaluation was based mostly on a hospital study, though student rural medical aides were used. It would have been useful to assess its practicability in conditions found in rural health centres and dispensaries. Recently the BBC television series Horizon2 ran a programme on the Tanzanian health services which showed the use of these charts by a group of students (or health workers), one looking up the charts while another performed the examinations on the patient.2 But more often there is only one health worker who has to examine the patient and follow the appropriate charts-all in under three minutes.
BRITISH MEDICAL JOURNAL
28 FEBRUARY 1976
Probably the real value of the charts is in training health workers for primary care and as a reference for the difficult case. Secondly, how foolproof is the technique? It has been designed for maximum efficiency in circumstances where even medical professionals perform badly. Essex found that in only 6% of cases were the diagnoses incorrect when the charts were used by an inexperienced medical student. We do not know the error rates for doctors in normal conditions, let alone in a 200-patient clinic. The real question is whether diagnostic accuracy in such a clinic is improved by using the flow chart technique. The evidence suggests that it is, but more evaluation is needed. Perhaps the most valuable contribution of Essex's book is that it may focus attention on the problem of ambulatory care in developing countries. It should not, however, detract attention from the underlying problem of allocation of resources. Two-hundred-patient clinics would not exist if more resources could be found for primary care services, preventive measures, and promotion of health.
2
Essex, B J, Diagnostic Pathways in Clinical Medicine. Edinburgh Mrican Medical and Research Foundation in conjunction with Churchill Livingstone, 1975. Horizon, BBC2, 19 January 1976.
Compensation for congenital defects In giving the Congenital Disabilities (Civil Liability) Bill a second reading,' members on both sides of the House of Commons acknowledged it as an interim measure designed to cover the period until the report of Lord Pearson's Royal Commission on Civil Liability and Compensation for Personal Injury. The Bill itself is in broadly the same terms as that suggested by the Law Commission in its 1974 report2 on injuries to unborn children, and in particular gives a child a right to sue for injuries received before birth. Hence it is all the more surprising that Lord Pearson should publicly have expressed the misgivings of himself and his colleagues3 about the Bill, adding that they had made their attitude clear to ministers. Lord Pearson's anxiety was caused mostly by the practical difficulty of deciding the cause of congenital defects, but he misjudged the intention of MPs if he thought they saw the Bill as a long-term solution to the problem of compensation for fetal injury-for they fully appreciated the drawbacks inevitable in a Bill forced to tackle antenatal injuries using the tools of the current law of tort. Indeed, the Bill is not so much law reform as a declaration of the modern common law on the right to sue for fetal injury. True, there has been no decided case in England, but in Canada and Australia damages have been awarded for fetal injury, and in 1973 the defendant abandoned an appeal to the Privy Council from the Victoria Full Court's award5 to a girl whose brain injuries were said to have been the result of her mother's car crash. Nonetheless, doubts about the state of the law in 1968 were a major factor in persuading the children whose mothers had taken thalidomide to settle for 40% of the normal measure of compensation. If Mr Carter's new Bill lays such doubts for ever to rest it will have performed some service. But there are numerous aspects of the Bill which show just how misguided it is to deal with fetal injuries within the framework of the
BRITISH MEDICAL JOURNAL
28 FEBRUARY 1976
current law of civil injury (tort). For example, the Bill provides that in the case of preconceptual injuries there should be no liability if either or both of the child's parents knew of the risk of its being born disabled. That could cause much distress to the parents, as could the indeterminate obligation imposed upon the court to reduce the damages where a parent shared the responsibility for the child being born disabled. In future trials a mother's conduct during the pregnancy would, therefore have to be investigated. The Bill even makes it possible to exclude liability to a child by a contract previously made with its mother. Mr Carter's Bill will probably not provide a remedy for even one in a thousand of the handicapped children born in Britain, who will still be confronted with overwhelming difficulties in proving the physical cause of their deformity and will still be obliged to shoulder the burden of proving the defendant negligent. Nor does the Bill really deal with teratogenic drugs, for English judges lag far behind their American brethren in the creation of "products liability." Mr Ron Lewis's attempt to solve the problem-the Dangerous Drugs and Disabled Children Bill of 1972-never reached the statute book. His Bill provided for an action to lie against the manufacturer, seller, or distributor of any drug not reasonably safe for the purpose for which it was intended to be used. A child could then have claimed damages in respect of injuries sustained through his parents' use of the drug. Naturally, a weighty objection to this Bill was the fear that never again would pharmaceutical companies risk placing new drugs on the market. Lord Pearson's controversial letter to The Times hinted that a different system of compensation resting on considerations of policy novel to English law may be being considered by his Commission. But even under a "no-fault" system based on the New Zealand model there would still be a division between those children who were granted large capital sums for traumatic or accidental injuries and those whose disabilities were the result of no identifiable external cause, and who would get nothing. The principle that all disabled children should be treated equally may one day prove more important than the traditional legal attitude that the wrongdoer must pay. What is needed is a fair allocation of available resources (perhaps on the model of the Rowntree Trust Fund) so that parents receive adequate grants, rather than compensation, to help in the task of educating and rehabilitating all subnormal and handicapped children. There are considerable powers already available under the Chronically Sick and Disabled Persons Act 1970. That Act should be made to work and, if necessary, be extended. Hansard: vol 904, col 1589. 6 February, 1976. Law Commission, Report on Injuries to Unborn Children. London, HMSO, 1974. 3 Lord Pearson, The Times, 28 January 1976. 4British Medical Journal, 1973, 1, 244. 5 Watt v Rama (1972) VR 353.
2
Diagnosis of intracranial haemorrhage Hounsfield's' new radiological technique of computerised axial tomography with the EMI brain scanner has completely revolutionised the diagnosis of intracranial haemorrhage. Certainly in the last two generations radiology has been the main means to the diagnosis, at first rather crude and then
483
gradually improving. In 1936 a rather rare but pathognomonic pneumographic sign for chronic subdural haematoma was described2 and in 1940 a characteristic deformity of the ventricular system was shown3 to be produced by the same condition; but until angiography became well established no further advances were made. With the advent of isotope scanning hopes were raised of greater accuracy, but while the technique does often identify haematomas the method is not entirely reliable. Very shortly after Ambrose4 began work on Hounsfield's prototype scanner he found that haematomas had a pathognomonic appearance. This results from the fact that extruded blood absorbs photons more than does brain tissue and that the different attenuation levels can be displayed. In terms of Hounsfield numbers, normal brain ranges between 12 and 18; tumours rate a little higher depending on the type, sometimes lower and occasionally even the same, but, apart from meningiomas, some metastases, and calcified masses (the last often differentiated by being visible on a plain x-ray film), none approaches a figure of 30, which is the density of extruded blood. Blood gives a figure in this range almost immediately after the ictus. Not surprisingly, therefore, the method has helped enormously in the differential diagnosis of "stroke." It will usually separate haematoma from infarct, from haemorrhagic infarct, and from tumour. Infarcts behave in the opposite way to haemorrhages by having a lower density than normal brain, while tumours show varying densities and they often become denser after the intravenous injection of a contrast agentso-called contrast enhancement. As might be expected, a haemorrhagic infarct shows a mixture of high and low densities without enhancement. Lesions as small as 1 cm may be detected. Basically there are two groups of brain haemorrhage to be considered, the spontaneous and traumatic. The former is most commonly associated with rupture of an aneurysm, an arteriovenous malformation, or a diseased artery, often secondary to hypertension. In a recent series of 100 cases Hayward and O'Reilly5 showed that a ruptured aneurysm can nearly always be differentiated from a primary intracerebral haemorrhage by noting the anatomical site. For example, a haematoma in the cavum of the septum lucidum or in the corpus callosum spells a ruptured anterior cerebral artery aneurysm, while a haematoma in the caudate nucleus or thalamus spells a primary haemorrhage. Their preangiographic diagnosis with computerised axial tomography was so accurate that in many instances angiography became redundant. One of the great advantages of the technique is that it allows the clinician to undertake serial examinations. While no one would hesitate to follow the radiological appearances of a case of pneumonia or gastric ulcer by repeated x-ray examinations, up till recently there has been reluctance to follow brain lesions because the techniques have been invasive, usually requiring an anaesthetic each time. Now, using computerised tomography, Cronqvist6 et al have shown the changing picture which occurs in haematomas, infarcts, and haemorrhagic infarcts over days and weeks. The haematoma gradually becomes absorbed in those patients who survive and its density lessens. Some infarcts ultimately disappear on the scan. Rupture of the haematoma of whatever cause into the ventricular system is not uncommon, and may readily be recognised by the new method: since the scan is performed with the patient supine, blood entering the ventricles gravitates to the posterior part.
Anitschkow, N, and Chalatow, S, Zentralblatt fur allgemeine Pathologie und pathologische Anatomie, 1913, 24, 1. Finlayson, R,J_ournal of Zoology, 1965, 147, 239. 8 Adams, C W M, Bayliss, 0 B, and Turner, D R, 7ournal of Pathology, 1975, 116, 225. 9 Wilens, S L, American Journal of Pathology, 1947, 23, 793. 10 Geer, J C, and McGill, H C, in Atherosclerotic Vascular Disease, eds A N Brest and J H Moyer. London, Butterworths, 1967. p. 8. 1 Blankenhorn, D, in Proceedings of International Workshop-Conference on Atherosclerosis, London, Ontario. To be published 1976. 6
7
Crowded clinics Throughout Africa may be found crowded outpatient clinics where 200 or more patients have to be seen in a morning by one health worker. The combination of the large burden of ill health in the population, their increasing faith in the efficacy of western-type medical treatment, and free or cheap health care makes the demand for primary care out of all proportion to the provision of services. Furthermore, commercial pharmacies do not exist outside the major cities, and lack of knowledge about disease inhibits the practice of self-care for minor illnesses. It follows that many of the outpatients have minor ailments which do not require the attention of skilled health workers. Nevertheless, when there is less than three minutes to spend per patient, to recognise those needing attention from among the crowds is itself a skilled task not normally taught. To help improve diagnostic skills whenever many patients must be seen in a short time Essex has developed a method using problem-orientated flow charts,' and this has proved effective in Tanzania. The presenting symptom is taken as a starting point, and the health worker is then guided through a series of pertinent questions and examinations. The scheme also gives some excellent guidance on community diagnoses-a fundamental prerequisite for the diagnosis of individual patients in a busy clinic. How many health workers, for example, at health centres or dispensaries know how much tuberculosis they ought to be diagnosing? Essex's book is intended primarily for use by medical auxiliaries (oedema is delightfully described, in true medical tradition, in terms of a ripe, pawpaw), but the foreword suggests that doctors, too, might find the charts useful for outpatient diagnosis when time is a major constraint. The method is a radical departure from the conventional methods of history taking and diagnosis usually taught in the relaxed atmosphere of a hospital ward, but Essex emphasises that the technique should only be used by senior students who have already been taught "properly." That may be an arguable proposition, but undoubtedly problem-orientated flow charts, modified to lower the thresholds for referral, could prove invaluable in teaching basic auxiliaries, such as the part-time village health worker so much in vogue at present. Two questions arise. Firstly, how practicable is the method for routine use in a busy polyclinic? Unfortunately Essex's evaluation was based mostly on a hospital study, though student rural medical aides were used. It would have been useful to assess its practicability in conditions found in rural health centres and dispensaries. Recently the BBC television series Horizon2 ran a programme on the Tanzanian health services which showed the use of these charts by a group of students (or health workers), one looking up the charts while another performed the examinations on the patient.2 But more often there is only one health worker who has to examine the patient and follow the appropriate charts-all in under three minutes.
BRITISH MEDICAL JOURNAL
28 FEBRUARY 1976
Probably the real value of the charts is in training health workers for primary care and as a reference for the difficult case. Secondly, how foolproof is the technique? It has been designed for maximum efficiency in circumstances where even medical professionals perform badly. Essex found that in only 6% of cases were the diagnoses incorrect when the charts were used by an inexperienced medical student. We do not know the error rates for doctors in normal conditions, let alone in a 200-patient clinic. The real question is whether diagnostic accuracy in such a clinic is improved by using the flow chart technique. The evidence suggests that it is, but more evaluation is needed. Perhaps the most valuable contribution of Essex's book is that it may focus attention on the problem of ambulatory care in developing countries. It should not, however, detract attention from the underlying problem of allocation of resources. Two-hundred-patient clinics would not exist if more resources could be found for primary care services, preventive measures, and promotion of health.
2
Essex, B J, Diagnostic Pathways in Clinical Medicine. Edinburgh Mrican Medical and Research Foundation in conjunction with Churchill Livingstone, 1975. Horizon, BBC2, 19 January 1976.
Compensation for congenital defects In giving the Congenital Disabilities (Civil Liability) Bill a second reading,' members on both sides of the House of Commons acknowledged it as an interim measure designed to cover the period until the report of Lord Pearson's Royal Commission on Civil Liability and Compensation for Personal Injury. The Bill itself is in broadly the same terms as that suggested by the Law Commission in its 1974 report2 on injuries to unborn children, and in particular gives a child a right to sue for injuries received before birth. Hence it is all the more surprising that Lord Pearson should publicly have expressed the misgivings of himself and his colleagues3 about the Bill, adding that they had made their attitude clear to ministers. Lord Pearson's anxiety was caused mostly by the practical difficulty of deciding the cause of congenital defects, but he misjudged the intention of MPs if he thought they saw the Bill as a long-term solution to the problem of compensation for fetal injury-for they fully appreciated the drawbacks inevitable in a Bill forced to tackle antenatal injuries using the tools of the current law of tort. Indeed, the Bill is not so much law reform as a declaration of the modern common law on the right to sue for fetal injury. True, there has been no decided case in England, but in Canada and Australia damages have been awarded for fetal injury, and in 1973 the defendant abandoned an appeal to the Privy Council from the Victoria Full Court's award5 to a girl whose brain injuries were said to have been the result of her mother's car crash. Nonetheless, doubts about the state of the law in 1968 were a major factor in persuading the children whose mothers had taken thalidomide to settle for 40% of the normal measure of compensation. If Mr Carter's new Bill lays such doubts for ever to rest it will have performed some service. But there are numerous aspects of the Bill which show just how misguided it is to deal with fetal injuries within the framework of the
BRITISH MEDICAL JOURNAL
28 FEBRUARY 1976
current law of civil injury (tort). For example, the Bill provides that in the case of preconceptual injuries there should be no liability if either or both of the child's parents knew of the risk of its being born disabled. That could cause much distress to the parents, as could the indeterminate obligation imposed upon the court to reduce the damages where a parent shared the responsibility for the child being born disabled. In future trials a mother's conduct during the pregnancy would, therefore have to be investigated. The Bill even makes it possible to exclude liability to a child by a contract previously made with its mother. Mr Carter's Bill will probably not provide a remedy for even one in a thousand of the handicapped children born in Britain, who will still be confronted with overwhelming difficulties in proving the physical cause of their deformity and will still be obliged to shoulder the burden of proving the defendant negligent. Nor does the Bill really deal with teratogenic drugs, for English judges lag far behind their American brethren in the creation of "products liability." Mr Ron Lewis's attempt to solve the problem-the Dangerous Drugs and Disabled Children Bill of 1972-never reached the statute book. His Bill provided for an action to lie against the manufacturer, seller, or distributor of any drug not reasonably safe for the purpose for which it was intended to be used. A child could then have claimed damages in respect of injuries sustained through his parents' use of the drug. Naturally, a weighty objection to this Bill was the fear that never again would pharmaceutical companies risk placing new drugs on the market. Lord Pearson's controversial letter to The Times hinted that a different system of compensation resting on considerations of policy novel to English law may be being considered by his Commission. But even under a "no-fault" system based on the New Zealand model there would still be a division between those children who were granted large capital sums for traumatic or accidental injuries and those whose disabilities were the result of no identifiable external cause, and who would get nothing. The principle that all disabled children should be treated equally may one day prove more important than the traditional legal attitude that the wrongdoer must pay. What is needed is a fair allocation of available resources (perhaps on the model of the Rowntree Trust Fund) so that parents receive adequate grants, rather than compensation, to help in the task of educating and rehabilitating all subnormal and handicapped children. There are considerable powers already available under the Chronically Sick and Disabled Persons Act 1970. That Act should be made to work and, if necessary, be extended. Hansard: vol 904, col 1589. 6 February, 1976. Law Commission, Report on Injuries to Unborn Children. London, HMSO, 1974. 3 Lord Pearson, The Times, 28 January 1976. 4British Medical Journal, 1973, 1, 244. 5 Watt v Rama (1972) VR 353.
2
Diagnosis of intracranial haemorrhage Hounsfield's' new radiological technique of computerised axial tomography with the EMI brain scanner has completely revolutionised the diagnosis of intracranial haemorrhage. Certainly in the last two generations radiology has been the main means to the diagnosis, at first rather crude and then
483
gradually improving. In 1936 a rather rare but pathognomonic pneumographic sign for chronic subdural haematoma was described2 and in 1940 a characteristic deformity of the ventricular system was shown3 to be produced by the same condition; but until angiography became well established no further advances were made. With the advent of isotope scanning hopes were raised of greater accuracy, but while the technique does often identify haematomas the method is not entirely reliable. Very shortly after Ambrose4 began work on Hounsfield's prototype scanner he found that haematomas had a pathognomonic appearance. This results from the fact that extruded blood absorbs photons more than does brain tissue and that the different attenuation levels can be displayed. In terms of Hounsfield numbers, normal brain ranges between 12 and 18; tumours rate a little higher depending on the type, sometimes lower and occasionally even the same, but, apart from meningiomas, some metastases, and calcified masses (the last often differentiated by being visible on a plain x-ray film), none approaches a figure of 30, which is the density of extruded blood. Blood gives a figure in this range almost immediately after the ictus. Not surprisingly, therefore, the method has helped enormously in the differential diagnosis of "stroke." It will usually separate haematoma from infarct, from haemorrhagic infarct, and from tumour. Infarcts behave in the opposite way to haemorrhages by having a lower density than normal brain, while tumours show varying densities and they often become denser after the intravenous injection of a contrast agentso-called contrast enhancement. As might be expected, a haemorrhagic infarct shows a mixture of high and low densities without enhancement. Lesions as small as 1 cm may be detected. Basically there are two groups of brain haemorrhage to be considered, the spontaneous and traumatic. The former is most commonly associated with rupture of an aneurysm, an arteriovenous malformation, or a diseased artery, often secondary to hypertension. In a recent series of 100 cases Hayward and O'Reilly5 showed that a ruptured aneurysm can nearly always be differentiated from a primary intracerebral haemorrhage by noting the anatomical site. For example, a haematoma in the cavum of the septum lucidum or in the corpus callosum spells a ruptured anterior cerebral artery aneurysm, while a haematoma in the caudate nucleus or thalamus spells a primary haemorrhage. Their preangiographic diagnosis with computerised axial tomography was so accurate that in many instances angiography became redundant. One of the great advantages of the technique is that it allows the clinician to undertake serial examinations. While no one would hesitate to follow the radiological appearances of a case of pneumonia or gastric ulcer by repeated x-ray examinations, up till recently there has been reluctance to follow brain lesions because the techniques have been invasive, usually requiring an anaesthetic each time. Now, using computerised tomography, Cronqvist6 et al have shown the changing picture which occurs in haematomas, infarcts, and haemorrhagic infarcts over days and weeks. The haematoma gradually becomes absorbed in those patients who survive and its density lessens. Some infarcts ultimately disappear on the scan. Rupture of the haematoma of whatever cause into the ventricular system is not uncommon, and may readily be recognised by the new method: since the scan is performed with the patient supine, blood entering the ventricles gravitates to the posterior part.
