ment at that time. Nevertheless, the finding that the difference between standard mortality ratios did not increase as the social class differences did during the 1970s suggests that this north-south gap may not reflect socioeconomic inequalities as closely as Dr Davey Smith and colleagues suppose.
Prescribed Respiratory Diseases,' and doctors from the eight regional medical boarding centres are happy to provide advice or answer queries on an informal basis. D H YATES Department of Social Security, London SEI IHU
IAN LECK
University of Manchester, Manchester M 13 9PT 1 Davey Smith G, Bartley M, Blane D. The Black report on socioeconomic inequalities in health 10 years on. Br Med J 1990;301:373-7. (18-25 August.) 2 Blane D, Davey Smith G, Bartlev M. Social class differences in years of potential life lost: size, trends, and principal causes. BrMedj 1990;301:429-32. (I September.) 3 Leck I. The north-south divide in England: implications for health care resource allocation. Community Med 1989;11: 102-7. 4 Office of Population Censuses and Surveys. Mortality statistics area: review of the Registrar General on deaths by area of usual residence in England and Wales 1986, 1987, 1988. London: HMSO, 1989 and 1990. (Series DH5 Nos 13-15.)
Asbestos diseases and compensation SIR,-Professor Anthony Seaton highlights many of the issues that surround the difficult issue of compensation for asbestos related diseases.' It may be useful to offer some practical details for doctors wishing to advise patients to claim Industrial Disablement Benefit as well as to provide some more accurate statistics regarding Ciaims. The application form to request at the local social security office is the BI lOO(Pn). Asbestosis is classified as a pneumoconiosis, and thus is included in prescribed disease number Dl (PD Dl), mesothelioma is PD D3, bilateral diffuse pleural thickening PD D9, and lung cancer in association with asbestosis or bilateral diffuse pleural thickening PD D8. It may be worth helping patients to fill in the form as they may not be clear exactly which disease they have or when it started. Accuracy in designating the disease is important as claims for malignant diseases are treated especially urgently. Details regarding hospital attendance are also important as they enable the notes to be requested in advance, thus speeding up the claim. The form also asks the date on which the claimant first had the disease, and it should be emphasised that this date is not the date of diagnosis but that of first onset of symptoms. Patients too unwell to travel can be visited at home or in hospital by the medical board. If the patient is unaware of the diagnosis or there are other complications, a letter from the hospital doctor or general practitioner is always carefully noted, and every effort is made to guard confidentiality. The table shows the figures for new awards of disablement benefit for asbestos related disease under the industrial injuries scheme over the past few years. It should be noted that some patients who develop carcinoma of the bronchus will already have been registered as having asbestosis and therefore will not be included in the figures. The 1989 data are to be published shortly. Further information regarding the scheme is available in the leaflet Pneumoconiosis and Other
1 Seaton A. Asbestos diseases and compensation. Br Med J 1990;301:453-4. (8 September.) 2 Department of Social Security. The social securitv statistics 1989. London: HMSO, 1989. 3 Department of Social Security. Pneumoconiosisandotherprescribed respirator diseases. London: DSS, 1989. (NI 226.)
Hereditary (primary) haemochromatosis SIR,-Dr Niall D C Finlayson rightly emphasises the importance of screening close relatives of patients with hereditary haemochromatosis,' but, unfortunately, treatment by venesection does not guarantee protection from developing primary hepatocellular carcinoma. Though Niederau et al did not find any case of primary hepatocellular carcinoma in haemochromatotic patients treated before the development of cirrhosis,2 my colleagues and I reported on two patients with primary haemochromatosis in whom hepatocellular carcinoma supervened in the absence of concomitant cirrhosis and despite removal of excess iron by venesection.3 Barry et al also described a patient without cirrhosis who developed primary hepatocellular carcinoma secondary to iron overload associated with hereditary spherocytosis.4 Though it is clear that treatment by venesection should be performed in patients with hereditary haemochromatosis and it is likely that the risk of development of hepatocellular carcinoma is greater if cirrhosis has developed, the possibility of this tumour arising in the absence of cirrhosis should be remembered. I W FELLOWS
Norfolk and Norwich Hospital, Norwich NR2 3TU I Finlayson NDC. Hereditary (primary) haemochromatosis.
BrMedj 1990;301:350-1. (18-25 August.) 2 Niederau C, Fisher R, Sonnenberg A, Stremmel W, Trampisch HJ, Stromeyer G. Survival and causes of death in cirrhotic and in non-cirrhotic patients with primary haemochromatosis. N EngljMed 1985;313:1256-62. 3 Fellows IW, Stewart M, Jeffcoate WJ, Smith PG, Toghill PJ. Hepatocellular carcinoma in primary haemochromatosis in the absence of cirrhosis. Gut 1988;29:1603-6. 4 Barry M, Scheuer PJ, Sherlock S, Ross CF, Williams R. Hereditary spherocytosis with secondary haemochromatosis. Lancet 1968;ii:481-5.
Extracorporeal membrane oxygenation SIR, -Dr A W Sosnowski and colleagues suggest a randomised trial should be undertaken to assess whether extracorporeal membrane oxygenation should be established in centres around Britain.' Certainly many neonates have benefited from this treatment in the United States, but American hospitals cater for a different population and
Number of new recipients of disablement benefit for asbestos related disease byyear No of new awards for:
1984 1985 1986 1987 1988
Asbestosis
Mesothelioma
Bilateral diffuse pleural thickening*
Carcinoma of the bronchus associated with asbestosis or bilateral diffuse pleural thickening*
290 301 329 282 224
201 250 306 399 479
63 114 117 117
8 34 55 59
*First "prescribed" on 1 April 1985.
BMJ VOLUME 301
22 SEPTEMBER 1990
have different obstetric support. The authors do not mention that there has been a large learning curve for all centres initiating extracorporeal membrane oxygenation (Extra Corporeal Life Support Organisation, unpublished data). Thus, if a trial were set up at the moment it would be comparing arguably poor techniques of extracorporeal membrane oxygenation with good conventional techniques. One must certainly encourage progress in conditions for which conventional treatment is not yet perfect, but it would be sensible to gain the necessary expertise in the new technique. Furthermore, there is a considerable financial implication in establishing extracorporeal membrane oxygenation centres. I surveyed all neonatal units in the West Midlands region with the intention of establishing an extracorporeal membrane oxygenation centre. Fifty eight letters were sent to 20 units, and I received 29 individual or corporate replies from 16 of the 20 units. Only one unit rejected establishing a centre on medical grounds, and one person thought it similarly unjustified. Thus 15 of the 16 units welcomed the potential establishment of a centre in the region. Of the 15 units, five thought that there was insufficient finance for the present conventional intensive care treatment and that there were insufficient intensive care facilities in the region, and thus the cost of setting up an extracorporeal membrane oxygenation service could not be justified. This also was the sentiment of the regional neonatal advisory group. This, I think, is sound advice and should be taken on board as there are undoubtedly insufficient neonatal intensive care facilities at present. The reference of Dr Sosnowski and colleagues to the use of extracorporeal membrane oxygenation in diaphragmatic hernia is misleading. The treatment is indicated in only a few infants with this condition. The only reversible aspect of this congenital abnormality is the abnormal distribution of smooth muscles throughout the pulmonary tree. This may regress in the first week after the operation, but regression is by no means a certainty. Thus only infants who yield normal blood gas concentrations at least once on conventional treatment should be considered for extracorporeal membrane oxygenation, and many centres believe that extracorporeal membrane oxygenation is inappropriate for treating congenital diaphragmatic hernia. STEPHEN J ROSE East Birmingham Hospital, Birmingham B9 5ST I Sosnowski AW, Bonser SJ, Field DJ, Graham TR, Firmin RK. Extracorporeal membrane oxygenation. Br Med J 1990;301: 303-4. (11 August.)
Management of severe burns SIR,-We would like to comment on the comprehensive review by Messrs Colin Robertson and Oliver Fenton,' which rightly includes injury from smoke inhalation-an important cause of death in victims of fire.2 Firstly, in the presence of carboxyhaemoglobin, conventional electrode blood gas analysers display erroneously high values for the calculated oxygen saturation and content, giving the unwary a false sense of security. In these circumstances pulse oximetry is also inaccurate. A blood oximeter, however, accurately determines oxygen saturation and content and also rapidly measures carboxyhaemoglobin concentrations. Secondly, the cyanide antidote they mention, dicobalt edetate, is standard treatment for massive poisoning in cases of ingestion or industrial accident. It may not be appropriate, however, for patients who have inhaled smoke as poisoning by inhalation is limited, with no further absorption after respiratory arrest or rescue. In the presence of
609
Prescribed Respiratory Diseases,' and doctors from the eight regional medical boarding centres are happy to provide advice or answer queries on an informal basis. D H YATES Department of Social Security, London SEI IHU
IAN LECK
University of Manchester, Manchester M 13 9PT 1 Davey Smith G, Bartley M, Blane D. The Black report on socioeconomic inequalities in health 10 years on. Br Med J 1990;301:373-7. (18-25 August.) 2 Blane D, Davey Smith G, Bartlev M. Social class differences in years of potential life lost: size, trends, and principal causes. BrMedj 1990;301:429-32. (I September.) 3 Leck I. The north-south divide in England: implications for health care resource allocation. Community Med 1989;11: 102-7. 4 Office of Population Censuses and Surveys. Mortality statistics area: review of the Registrar General on deaths by area of usual residence in England and Wales 1986, 1987, 1988. London: HMSO, 1989 and 1990. (Series DH5 Nos 13-15.)
Asbestos diseases and compensation SIR,-Professor Anthony Seaton highlights many of the issues that surround the difficult issue of compensation for asbestos related diseases.' It may be useful to offer some practical details for doctors wishing to advise patients to claim Industrial Disablement Benefit as well as to provide some more accurate statistics regarding Ciaims. The application form to request at the local social security office is the BI lOO(Pn). Asbestosis is classified as a pneumoconiosis, and thus is included in prescribed disease number Dl (PD Dl), mesothelioma is PD D3, bilateral diffuse pleural thickening PD D9, and lung cancer in association with asbestosis or bilateral diffuse pleural thickening PD D8. It may be worth helping patients to fill in the form as they may not be clear exactly which disease they have or when it started. Accuracy in designating the disease is important as claims for malignant diseases are treated especially urgently. Details regarding hospital attendance are also important as they enable the notes to be requested in advance, thus speeding up the claim. The form also asks the date on which the claimant first had the disease, and it should be emphasised that this date is not the date of diagnosis but that of first onset of symptoms. Patients too unwell to travel can be visited at home or in hospital by the medical board. If the patient is unaware of the diagnosis or there are other complications, a letter from the hospital doctor or general practitioner is always carefully noted, and every effort is made to guard confidentiality. The table shows the figures for new awards of disablement benefit for asbestos related disease under the industrial injuries scheme over the past few years. It should be noted that some patients who develop carcinoma of the bronchus will already have been registered as having asbestosis and therefore will not be included in the figures. The 1989 data are to be published shortly. Further information regarding the scheme is available in the leaflet Pneumoconiosis and Other
1 Seaton A. Asbestos diseases and compensation. Br Med J 1990;301:453-4. (8 September.) 2 Department of Social Security. The social securitv statistics 1989. London: HMSO, 1989. 3 Department of Social Security. Pneumoconiosisandotherprescribed respirator diseases. London: DSS, 1989. (NI 226.)
Hereditary (primary) haemochromatosis SIR,-Dr Niall D C Finlayson rightly emphasises the importance of screening close relatives of patients with hereditary haemochromatosis,' but, unfortunately, treatment by venesection does not guarantee protection from developing primary hepatocellular carcinoma. Though Niederau et al did not find any case of primary hepatocellular carcinoma in haemochromatotic patients treated before the development of cirrhosis,2 my colleagues and I reported on two patients with primary haemochromatosis in whom hepatocellular carcinoma supervened in the absence of concomitant cirrhosis and despite removal of excess iron by venesection.3 Barry et al also described a patient without cirrhosis who developed primary hepatocellular carcinoma secondary to iron overload associated with hereditary spherocytosis.4 Though it is clear that treatment by venesection should be performed in patients with hereditary haemochromatosis and it is likely that the risk of development of hepatocellular carcinoma is greater if cirrhosis has developed, the possibility of this tumour arising in the absence of cirrhosis should be remembered. I W FELLOWS
Norfolk and Norwich Hospital, Norwich NR2 3TU I Finlayson NDC. Hereditary (primary) haemochromatosis.
BrMedj 1990;301:350-1. (18-25 August.) 2 Niederau C, Fisher R, Sonnenberg A, Stremmel W, Trampisch HJ, Stromeyer G. Survival and causes of death in cirrhotic and in non-cirrhotic patients with primary haemochromatosis. N EngljMed 1985;313:1256-62. 3 Fellows IW, Stewart M, Jeffcoate WJ, Smith PG, Toghill PJ. Hepatocellular carcinoma in primary haemochromatosis in the absence of cirrhosis. Gut 1988;29:1603-6. 4 Barry M, Scheuer PJ, Sherlock S, Ross CF, Williams R. Hereditary spherocytosis with secondary haemochromatosis. Lancet 1968;ii:481-5.
Extracorporeal membrane oxygenation SIR, -Dr A W Sosnowski and colleagues suggest a randomised trial should be undertaken to assess whether extracorporeal membrane oxygenation should be established in centres around Britain.' Certainly many neonates have benefited from this treatment in the United States, but American hospitals cater for a different population and
Number of new recipients of disablement benefit for asbestos related disease byyear No of new awards for:
1984 1985 1986 1987 1988
Asbestosis
Mesothelioma
Bilateral diffuse pleural thickening*
Carcinoma of the bronchus associated with asbestosis or bilateral diffuse pleural thickening*
290 301 329 282 224
201 250 306 399 479
63 114 117 117
8 34 55 59
*First "prescribed" on 1 April 1985.
BMJ VOLUME 301
22 SEPTEMBER 1990
have different obstetric support. The authors do not mention that there has been a large learning curve for all centres initiating extracorporeal membrane oxygenation (Extra Corporeal Life Support Organisation, unpublished data). Thus, if a trial were set up at the moment it would be comparing arguably poor techniques of extracorporeal membrane oxygenation with good conventional techniques. One must certainly encourage progress in conditions for which conventional treatment is not yet perfect, but it would be sensible to gain the necessary expertise in the new technique. Furthermore, there is a considerable financial implication in establishing extracorporeal membrane oxygenation centres. I surveyed all neonatal units in the West Midlands region with the intention of establishing an extracorporeal membrane oxygenation centre. Fifty eight letters were sent to 20 units, and I received 29 individual or corporate replies from 16 of the 20 units. Only one unit rejected establishing a centre on medical grounds, and one person thought it similarly unjustified. Thus 15 of the 16 units welcomed the potential establishment of a centre in the region. Of the 15 units, five thought that there was insufficient finance for the present conventional intensive care treatment and that there were insufficient intensive care facilities in the region, and thus the cost of setting up an extracorporeal membrane oxygenation service could not be justified. This also was the sentiment of the regional neonatal advisory group. This, I think, is sound advice and should be taken on board as there are undoubtedly insufficient neonatal intensive care facilities at present. The reference of Dr Sosnowski and colleagues to the use of extracorporeal membrane oxygenation in diaphragmatic hernia is misleading. The treatment is indicated in only a few infants with this condition. The only reversible aspect of this congenital abnormality is the abnormal distribution of smooth muscles throughout the pulmonary tree. This may regress in the first week after the operation, but regression is by no means a certainty. Thus only infants who yield normal blood gas concentrations at least once on conventional treatment should be considered for extracorporeal membrane oxygenation, and many centres believe that extracorporeal membrane oxygenation is inappropriate for treating congenital diaphragmatic hernia. STEPHEN J ROSE East Birmingham Hospital, Birmingham B9 5ST I Sosnowski AW, Bonser SJ, Field DJ, Graham TR, Firmin RK. Extracorporeal membrane oxygenation. Br Med J 1990;301: 303-4. (11 August.)
Management of severe burns SIR,-We would like to comment on the comprehensive review by Messrs Colin Robertson and Oliver Fenton,' which rightly includes injury from smoke inhalation-an important cause of death in victims of fire.2 Firstly, in the presence of carboxyhaemoglobin, conventional electrode blood gas analysers display erroneously high values for the calculated oxygen saturation and content, giving the unwary a false sense of security. In these circumstances pulse oximetry is also inaccurate. A blood oximeter, however, accurately determines oxygen saturation and content and also rapidly measures carboxyhaemoglobin concentrations. Secondly, the cyanide antidote they mention, dicobalt edetate, is standard treatment for massive poisoning in cases of ingestion or industrial accident. It may not be appropriate, however, for patients who have inhaled smoke as poisoning by inhalation is limited, with no further absorption after respiratory arrest or rescue. In the presence of
609
