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PULMONARY THROMBOEMBOLISM
91
be due to breakdown of lysosomes.44 These effects, and the release of lysosomal enzymes by ultraviolet irradiation,5 can be inhibited by hydrocortisone, which stabilises the lysosomal membranes. Moreover, the work of LEJEUNE et al.6indicates that an enzyme—K-(14)-glucosidase—capable of hydrolysing glycogen, is localised within lysosomal particles. Deficiency of this enzyme leads to one type of glycogenstorage disease. There is also evidence that lysosomal enzymes are activated in cells infected with virulent viruses, and that this may contribute to cytopathic
likewise
appears to
effects.’7 The work initiated by DE DUVE is already proving very useful in the study of connective-tissue and other diseases. Its implications in experimental pathology are only just beginning to emerge; but we can be sure that studies of lysosomes, and the factors leading to their disintegration and stabilisation, will uncover many other interesting facts in the next few years.
School—and After WRITING on the school health service (p. 101), Dr. DIDSBURY points out that " in each age and society methods of health promotion must be adjusted to
changed circumstances and challenges ". A special correspondent of The Times8 says much the same thing. " The School Health
"
Service ", he believes, is under-
going a reassessment of its functions and philosophies." Both writers want the service to be closely linked with
he roundly criticises) linked with the school health service by a joint appointment, shared with a reinforced youth employment service. Over sixteen years have passed since the recommendation that there should be a medical adviser to the youth employment officer; yet so far not even the Central Youth Employment Executive has a medical adviser. Moreover, there is no connection between the appointed factory doctor and the school health service or the youth employment service, and no medical records are available at the statutory examinations, which may be done at the rate of 12 to 20 an hour, often in a surgery away from the factory, where the doctor knows little about the work situation. The appointed factory doctor generally sees those in least need of help, often because the less desirable firms do not notify; and it is small wonder that good firms regard the present procedure as futile. If the school-leaving age is going to be raised, this will at least abolish the wasteful gap between leaving school at 15 and starting an apprenticeship at 16. It is estimated that at present 80% of children are left largely to their own 11 resources. In 1949 the Gowers report proposed that medical supervision should be extended to all young people under 18 regardless of occupation. What is needed is a coordinating framework " between school and work. An experimental scheme in one area might be a basis for a national approach, and The Times article concludes with a plea for an interdepartmental committee to settle the responsibilities of the Ministries of Health, Education, and Labour. As Dr. DIDSBURY says, our school medical service was designed at the beginning of the century to cope with conditions that no longer exist". If there is now a case for restricting the services offered at school age, there is an even stronger case for expanding the services young people need after school has been left behind.
people in factories
"
the life of the school and the teachers. Dr. DIDSBURY favours more selection of children for medical examination, with a health conference at which the head teacher will bring forward " the names of pupils who have caused concern to the teaching staff by ill health, absence from school, or behaviour in class ". The Times article emphasises that the school is a biological unit, and that, in the pupil’s last year at any rate, the medical and educational services should be an indivisible team. Dr. Annotations DIDSBURY would have the service brought into better relation also with the general practitioner; for children are PULMONARY THROMBOEMBOLISM members of a family group, and the family doctor is well Two types of pulmonary embolism are clearly recogplaced to practise preventive medicine, provided he is interested " in the early detection of disease in children, nised. The first follows a major surgical operation, A main in the simple dynamics of health and sickness in the particularly one which involves the pelvis. branch of the pulmonary artery is obstructed, and home, and in trying to ensure the health of the sudden death results. The second type, which individual child". He pleads, too, for more help commonly is found in patients with left ventricular failure and from the family doctor in the care of handicapped congested lungs, results in the typical pulmonary infarct. children. More recently a third type has been reported in which The Times writer thinks that the school health service recurring small emboli impact in the peripheral branches should be extended to youth in industry, " to see that of the pulmonary artery. This results in gradual reducthey are fit and preparing to maintain their fitness tion of the pulmonary vascular bed and eventually in mentally and physically in a world where attitudes of pulmonary hypertension. Small emboli can impact in mind, understanding and insight, are of fundamental im- the lungs without producing any immediate clinical 12 portance to adaptation and survival". Like HERFORD,9 10 symptoms. The source of this type of embolus is usually a thromhe wishes to see the statutory duties of the appointed bosed vein in the leg, pelvis, or arm; but tumour cells 13 "
factory doctor (whose present work in
relation
to
young
4. Fell, H. B., Thomas, L. J. exp. Med. 1960, 111, 719. 5. Weissmann, G., Fell, H. B. ibid. 1962, 116, 365. 6. Lejeune, N., Thinès-Sempou, O., Hers, H. G. Biochem J. 1963, 86, 16. 7. Allison, A. C., Sandelin, K. J. exp. Med. 1963, 117, 879. 8. Times, Oct. 21, 1963, p. 11 9. Herford, M. E. M. Youth at Work. London, 1957; see Lancet 1957, 1, 1026. 10. Herford, M. E. M. ibid. 1960, ii, 1353; 1963, ii, 837.
and bilharzia ova 14 are other possible sources. Even if one of the smaller branches of the pulmonary artery is involved there is stasis in this vessel, and thrombosis may 11. H.M. Stationery Office. 1949. Cmd 7664. 12. Allison, P. R., Dunnell, M. S., Marshall, R. Thorax, 1960, 15, 273. 13. McMichael, J. Edinb. med. J. 1948, 55, 65. 14. Bedford, D. E., Aidances, S. M., Girgis, B. Brit. Heart J. 1946, 8, 87.
92
spread centrally to involve the major pulmonary arteries. Polycythsemia can increase the tendency to central spread of the thrombosis. When an appreciable area of the lung is involved, the patient presents with dyspnoea and slight non-productive cough. Clinical examination reveals very little except evidence of pulmonary hypertension and electrocardiographic signs of right ventricular hypertrophy. There is no other cardiac abnormality. Crispin et al.I5 have shown that radiology can contribute to the diagnosis of obstructive pulmonary hypertension and thromboembolism. They have reviewed the X-ray changes in patients in whom the clinical presentation has been discussed by Goodwin et al.I6 Their patients tend to fall into two major groups: (1) those having obstruction of a major pulmonary vessel, and (2) those in whom the obstruction is confined to the smaller branches of the pulmonary artery. In the first group, the appearances on the chest films are those of oligaemia of the affected areas of the lung, with hyperxmia elsewhere." The right ventricle and its outflow tract may be enlarged and the hilar arteries dilated as a result of the pulmonary hypertension. There may also be evidence of right inflow stasis-namely, dilation of the azygos vein and the superior vena cava. In the second group, where only smaller branches of the pulmonary artery are involved, the chest radiograph may be remarkably normal. In both groups, pulmonary angiography has proved of great value in demonstrating the degree of pulmonary involvement. This is particularly true of the second group, where the plain film may be normal. In the first group (major arteries involved) the degree of obstruction is readily appreciated. The peripheral vessels are either poorly filled or not filled at all, and the pulmonary veins in these areas are not seen. In areas where there is compensatory hyperxmia, the vessels fill early and appear larger, and the pulmonary veins appear early. In the second group (only smaller pulmonary arteries involved) the pulmonary angiogram is even more valuable in demonstrating the underlying lesion. In the affected areas of the lung the vessels are diminished and their branches irregularly pruned. The rate of passage of the dye is reduced, and, where the major artery is patent, abnormal dilated tortuous vessels may be seen. Pulmonary angiography reveals that certain areas of the lungs are well ventilated but not perfused with blood-which probably accounts for the low arterial oxygen saturation in these patients. The reticular pattern seen in the involved areas on the straight film is probably due to dilated bronchial arteries. It has been shown that oxygen desaturation can produce vasospasm, and eventual fibrotic narrowing of the pul11 monary arterioles, with resulting pulmonary hypertension. 18 It seems likely, therefore, that a vicious circle may be initiated in which thromboembolism leads to oxygen desaturation which itself gives rise to vasoconstriction and
increasing pulmonary hypertension. This may help to explain some of the poor results following anticoagulant therapy. The microscopic appearances of the vessels involved in thromboembolism and in pulmonary hypertension are highly similar, especially where the vessel has been recanalised. Many cases hitherto termed idiopathic hypertension are probably examples of this condition;and the term idiopathic pulmonary hyper15.
Crispin, 705.
16. 17. 18.
A.
R., Goodwin, J. F., Steiner, R. E. Brit. J. Radiol. 1963, 36,
Goodwin, J. F., Harrison, C. V., Wilken, D. E. L. Brit. med. J. 1963, i, 701. Fleischner, F. G. Clin. Radiol. 1963, 13, 169. von Euler, U. S., Liljestrand, G. Acta physiol. scand. 1946, 12, 301.
tension should be confined to cases where pulmonary hypertension has been known to exist since infancy without evidence of a primary cardiac defect, and the microscopic appearances of the vessels are those of foetal type. CONGENITAL MALFORMATIONS
THE Ministry of Health is introducing a scheme for the notification of congenital malformations. From Jan. 1, the doctor or midwife who notifies the local medical officer of health of the fact of birth is asked to record, at the same time, any malformation discovered in the child. This is to be done whether the child is live or stillborn. The medical officer of health is to furnish further details subsequently, classifying the abnormality with the help of the doctors attending the child. The aim is to compile statistical data: no central record of individual cases will be kept. Since notification is to be voluntary, the success of the scheme will depend on doctors’ interest and cooperation. To encourage these the Ministry has distributed a booklet1 in which some of the medical and social aspects of congenital malformation are discussed. The medical officer of health who keeps an accurate record of handicapped children in his area can, it says, ensure that the health, welfare, and education services give all possible assistance to the children and their parents. The heaviest responsibility for helping these families must, however, remain the family doctor’s, and liaison between him and the social services cannot be established too soon in each instance. The booklet points out that there are defects which are immediately obvious at birth, others which must be deliberately sought, and yet others which do not betray their presence for some days or weeks. Presumably, under the scheme as it stands, these last will escape notification. But if the returns cannot be comprehensive, they should certainly be very useful. ALCOHOL IN THE BREATH
A Medical Research Council working party has supplied the Home Office and the Ministry of Transport with a report of its inquiries into methods of estimating the blood-alcohol by measuring the alcohol content of the breath. By the 1962 Road Traffic Act the Minister of Transport has power to authorise the use by the police of a breath-testing device when they suspect a driver of being drunk; and it seems that he will shortly use this power. Three methods were studied 2 : the ’Breathalyser’ using samples collected directly; the same machine applied to samples stored in plastic bags; and the newer Kitagawa-Wright detector. The chemical reaction is similar in each case-the reduction by ethyl alcohol of dichromate present in low concentration in 50% sulphuric acid-and the colour change is translated into an estimate of blood-alcohol. In the M.R.C. tests various doses of distilled spirits were given to 18 healthy young men, and the alcohol content of their alveolar air was measured each half-hour for several hours, using the three methods. Venous blood was analysed chemically for alcohol three times in each subject. All three methods proved suitable for practical use, the readings were reproducible, and they correlated well with blood analysis. The direct breathalyser readings showed a higher correlation with blood than the plastic-bag and the Kitagawa-Wright methods, but the differences were not quite significant. It was 1.
Congenital Malformations. Ministry
Gratis. 2. Begg, T. B., Hill, I. D.,
Nickolls,
of Health. London, 1963.
L. C. Brit. med. J. Jan.
Pp.
8.
4, 1964, p. 9.
be due to breakdown of lysosomes.44 These effects, and the release of lysosomal enzymes by ultraviolet irradiation,5 can be inhibited by hydrocortisone, which stabilises the lysosomal membranes. Moreover, the work of LEJEUNE et al.6indicates that an enzyme—K-(14)-glucosidase—capable of hydrolysing glycogen, is localised within lysosomal particles. Deficiency of this enzyme leads to one type of glycogenstorage disease. There is also evidence that lysosomal enzymes are activated in cells infected with virulent viruses, and that this may contribute to cytopathic
likewise
appears to
effects.’7 The work initiated by DE DUVE is already proving very useful in the study of connective-tissue and other diseases. Its implications in experimental pathology are only just beginning to emerge; but we can be sure that studies of lysosomes, and the factors leading to their disintegration and stabilisation, will uncover many other interesting facts in the next few years.
School—and After WRITING on the school health service (p. 101), Dr. DIDSBURY points out that " in each age and society methods of health promotion must be adjusted to
changed circumstances and challenges ". A special correspondent of The Times8 says much the same thing. " The School Health
"
Service ", he believes, is under-
going a reassessment of its functions and philosophies." Both writers want the service to be closely linked with
he roundly criticises) linked with the school health service by a joint appointment, shared with a reinforced youth employment service. Over sixteen years have passed since the recommendation that there should be a medical adviser to the youth employment officer; yet so far not even the Central Youth Employment Executive has a medical adviser. Moreover, there is no connection between the appointed factory doctor and the school health service or the youth employment service, and no medical records are available at the statutory examinations, which may be done at the rate of 12 to 20 an hour, often in a surgery away from the factory, where the doctor knows little about the work situation. The appointed factory doctor generally sees those in least need of help, often because the less desirable firms do not notify; and it is small wonder that good firms regard the present procedure as futile. If the school-leaving age is going to be raised, this will at least abolish the wasteful gap between leaving school at 15 and starting an apprenticeship at 16. It is estimated that at present 80% of children are left largely to their own 11 resources. In 1949 the Gowers report proposed that medical supervision should be extended to all young people under 18 regardless of occupation. What is needed is a coordinating framework " between school and work. An experimental scheme in one area might be a basis for a national approach, and The Times article concludes with a plea for an interdepartmental committee to settle the responsibilities of the Ministries of Health, Education, and Labour. As Dr. DIDSBURY says, our school medical service was designed at the beginning of the century to cope with conditions that no longer exist". If there is now a case for restricting the services offered at school age, there is an even stronger case for expanding the services young people need after school has been left behind.
people in factories
"
the life of the school and the teachers. Dr. DIDSBURY favours more selection of children for medical examination, with a health conference at which the head teacher will bring forward " the names of pupils who have caused concern to the teaching staff by ill health, absence from school, or behaviour in class ". The Times article emphasises that the school is a biological unit, and that, in the pupil’s last year at any rate, the medical and educational services should be an indivisible team. Dr. Annotations DIDSBURY would have the service brought into better relation also with the general practitioner; for children are PULMONARY THROMBOEMBOLISM members of a family group, and the family doctor is well Two types of pulmonary embolism are clearly recogplaced to practise preventive medicine, provided he is interested " in the early detection of disease in children, nised. The first follows a major surgical operation, A main in the simple dynamics of health and sickness in the particularly one which involves the pelvis. branch of the pulmonary artery is obstructed, and home, and in trying to ensure the health of the sudden death results. The second type, which individual child". He pleads, too, for more help commonly is found in patients with left ventricular failure and from the family doctor in the care of handicapped congested lungs, results in the typical pulmonary infarct. children. More recently a third type has been reported in which The Times writer thinks that the school health service recurring small emboli impact in the peripheral branches should be extended to youth in industry, " to see that of the pulmonary artery. This results in gradual reducthey are fit and preparing to maintain their fitness tion of the pulmonary vascular bed and eventually in mentally and physically in a world where attitudes of pulmonary hypertension. Small emboli can impact in mind, understanding and insight, are of fundamental im- the lungs without producing any immediate clinical 12 portance to adaptation and survival". Like HERFORD,9 10 symptoms. The source of this type of embolus is usually a thromhe wishes to see the statutory duties of the appointed bosed vein in the leg, pelvis, or arm; but tumour cells 13 "
factory doctor (whose present work in
relation
to
young
4. Fell, H. B., Thomas, L. J. exp. Med. 1960, 111, 719. 5. Weissmann, G., Fell, H. B. ibid. 1962, 116, 365. 6. Lejeune, N., Thinès-Sempou, O., Hers, H. G. Biochem J. 1963, 86, 16. 7. Allison, A. C., Sandelin, K. J. exp. Med. 1963, 117, 879. 8. Times, Oct. 21, 1963, p. 11 9. Herford, M. E. M. Youth at Work. London, 1957; see Lancet 1957, 1, 1026. 10. Herford, M. E. M. ibid. 1960, ii, 1353; 1963, ii, 837.
and bilharzia ova 14 are other possible sources. Even if one of the smaller branches of the pulmonary artery is involved there is stasis in this vessel, and thrombosis may 11. H.M. Stationery Office. 1949. Cmd 7664. 12. Allison, P. R., Dunnell, M. S., Marshall, R. Thorax, 1960, 15, 273. 13. McMichael, J. Edinb. med. J. 1948, 55, 65. 14. Bedford, D. E., Aidances, S. M., Girgis, B. Brit. Heart J. 1946, 8, 87.
92
spread centrally to involve the major pulmonary arteries. Polycythsemia can increase the tendency to central spread of the thrombosis. When an appreciable area of the lung is involved, the patient presents with dyspnoea and slight non-productive cough. Clinical examination reveals very little except evidence of pulmonary hypertension and electrocardiographic signs of right ventricular hypertrophy. There is no other cardiac abnormality. Crispin et al.I5 have shown that radiology can contribute to the diagnosis of obstructive pulmonary hypertension and thromboembolism. They have reviewed the X-ray changes in patients in whom the clinical presentation has been discussed by Goodwin et al.I6 Their patients tend to fall into two major groups: (1) those having obstruction of a major pulmonary vessel, and (2) those in whom the obstruction is confined to the smaller branches of the pulmonary artery. In the first group, the appearances on the chest films are those of oligaemia of the affected areas of the lung, with hyperxmia elsewhere." The right ventricle and its outflow tract may be enlarged and the hilar arteries dilated as a result of the pulmonary hypertension. There may also be evidence of right inflow stasis-namely, dilation of the azygos vein and the superior vena cava. In the second group, where only smaller branches of the pulmonary artery are involved, the chest radiograph may be remarkably normal. In both groups, pulmonary angiography has proved of great value in demonstrating the degree of pulmonary involvement. This is particularly true of the second group, where the plain film may be normal. In the first group (major arteries involved) the degree of obstruction is readily appreciated. The peripheral vessels are either poorly filled or not filled at all, and the pulmonary veins in these areas are not seen. In areas where there is compensatory hyperxmia, the vessels fill early and appear larger, and the pulmonary veins appear early. In the second group (only smaller pulmonary arteries involved) the pulmonary angiogram is even more valuable in demonstrating the underlying lesion. In the affected areas of the lung the vessels are diminished and their branches irregularly pruned. The rate of passage of the dye is reduced, and, where the major artery is patent, abnormal dilated tortuous vessels may be seen. Pulmonary angiography reveals that certain areas of the lungs are well ventilated but not perfused with blood-which probably accounts for the low arterial oxygen saturation in these patients. The reticular pattern seen in the involved areas on the straight film is probably due to dilated bronchial arteries. It has been shown that oxygen desaturation can produce vasospasm, and eventual fibrotic narrowing of the pul11 monary arterioles, with resulting pulmonary hypertension. 18 It seems likely, therefore, that a vicious circle may be initiated in which thromboembolism leads to oxygen desaturation which itself gives rise to vasoconstriction and
increasing pulmonary hypertension. This may help to explain some of the poor results following anticoagulant therapy. The microscopic appearances of the vessels involved in thromboembolism and in pulmonary hypertension are highly similar, especially where the vessel has been recanalised. Many cases hitherto termed idiopathic hypertension are probably examples of this condition;and the term idiopathic pulmonary hyper15.
Crispin, 705.
16. 17. 18.
A.
R., Goodwin, J. F., Steiner, R. E. Brit. J. Radiol. 1963, 36,
Goodwin, J. F., Harrison, C. V., Wilken, D. E. L. Brit. med. J. 1963, i, 701. Fleischner, F. G. Clin. Radiol. 1963, 13, 169. von Euler, U. S., Liljestrand, G. Acta physiol. scand. 1946, 12, 301.
tension should be confined to cases where pulmonary hypertension has been known to exist since infancy without evidence of a primary cardiac defect, and the microscopic appearances of the vessels are those of foetal type. CONGENITAL MALFORMATIONS
THE Ministry of Health is introducing a scheme for the notification of congenital malformations. From Jan. 1, the doctor or midwife who notifies the local medical officer of health of the fact of birth is asked to record, at the same time, any malformation discovered in the child. This is to be done whether the child is live or stillborn. The medical officer of health is to furnish further details subsequently, classifying the abnormality with the help of the doctors attending the child. The aim is to compile statistical data: no central record of individual cases will be kept. Since notification is to be voluntary, the success of the scheme will depend on doctors’ interest and cooperation. To encourage these the Ministry has distributed a booklet1 in which some of the medical and social aspects of congenital malformation are discussed. The medical officer of health who keeps an accurate record of handicapped children in his area can, it says, ensure that the health, welfare, and education services give all possible assistance to the children and their parents. The heaviest responsibility for helping these families must, however, remain the family doctor’s, and liaison between him and the social services cannot be established too soon in each instance. The booklet points out that there are defects which are immediately obvious at birth, others which must be deliberately sought, and yet others which do not betray their presence for some days or weeks. Presumably, under the scheme as it stands, these last will escape notification. But if the returns cannot be comprehensive, they should certainly be very useful. ALCOHOL IN THE BREATH
A Medical Research Council working party has supplied the Home Office and the Ministry of Transport with a report of its inquiries into methods of estimating the blood-alcohol by measuring the alcohol content of the breath. By the 1962 Road Traffic Act the Minister of Transport has power to authorise the use by the police of a breath-testing device when they suspect a driver of being drunk; and it seems that he will shortly use this power. Three methods were studied 2 : the ’Breathalyser’ using samples collected directly; the same machine applied to samples stored in plastic bags; and the newer Kitagawa-Wright detector. The chemical reaction is similar in each case-the reduction by ethyl alcohol of dichromate present in low concentration in 50% sulphuric acid-and the colour change is translated into an estimate of blood-alcohol. In the M.R.C. tests various doses of distilled spirits were given to 18 healthy young men, and the alcohol content of their alveolar air was measured each half-hour for several hours, using the three methods. Venous blood was analysed chemically for alcohol three times in each subject. All three methods proved suitable for practical use, the readings were reproducible, and they correlated well with blood analysis. The direct breathalyser readings showed a higher correlation with blood than the plastic-bag and the Kitagawa-Wright methods, but the differences were not quite significant. It was 1.
Congenital Malformations. Ministry
Gratis. 2. Begg, T. B., Hill, I. D.,
Nickolls,
of Health. London, 1963.
L. C. Brit. med. J. Jan.
Pp.
8.
4, 1964, p. 9.