BRITISH MEDICAL JOURNAL
8 FEBRUARY 1975
possible feature would be the presence or absence of abnormal chromosome sets. Karyotype abnormalities have repeatedly been found in cervical lesions, including many lesions with surface maturation.'3 It has been suggested14 that the presence of abnormal mitoses in paraffin sections should be taken as a major feature for a new definition of carcinoma in situ, but that criterion would certainly be open to differences in interpretation. If the enlarged nuclei present in the mildest dysplasias turned out to be simply polyploid, with normal chromosome sets, and if that could be reliably determined, a tidy separation might be possible. Direct chromosome preparations are almost impossible to make from the lesions with low mitotic activity, but some of the evidence from Feulgen microspectrophotometry tends to support this concept.'5 16 Further careful studies on the nuclear DNA content in lesions considered to be on the borderline of cervical neoplasia would be illuminating and might even permit a separation into three-those with simple polyploidy, those with a scatter of aneuploid values, and those showing the emergence of a new dominant clone. Only the last could justifiably carry the question-begging name carcinoma in situ. If such a distinction could be shown (and there are formidable technical difficulties) we would still be left with the problem of discovering whether the newly-defined pathological states have different clinical courses when left untreated. Treated cases provide no information, since their risk of developing invasive cancer of the cervix is already known to be practically zero.
Koss, L. G., et al., Cancer (Philadelphia), 1963, 16, 1160. Johnson, L. D., Obstetrical & Gynecological Survey, 1969, 24, 735. Richart, R. M., Pathology Annual 1973, ed. S. C. Sommers. New York, Appleton-Century-Crofts., 1973, p. 301. 4Reagan, J. W., and Patten, S. F., Annals of the New York Academy of Sciences, 1962, 97, 662. 5 Patten, S. F., Diagnostic Cytology of the Uterine Cervix. Basle, Karger, 1969. 6 Thomas, D. B., American3Journal of Epidemiology, 1973, 98, 10. Thomas, D. B., and Anderson, R. I., American J'ournal of Epidemiology, 1974, 100, 113. 8 Bettinger, H. F., and Reagan, J. W., in Proceedings of the First International Congress on Exfoliative Cytology, ed. G. L. Wied. Philadelphia, Lippincott, 1962, p. 283. 9 Novak, E. R., and Woodruff, J. D., Novak's Gynecologic and Obstetric Pathology, 7th edn. Philadelphia, Saunders, 1974. 10 Govan, A. D. T., et ai.,3Journal of Clinical Pathology, 1969, 22, 383. 1 Riotton, G., and Christopherson, W. M., Cytology of the Female Genital Tract. Geneva, World Health Organization, 1973. 12 Koss, L. G., Diagnostic Cytology and its Histopathologic Bases, 2nd edn. Philadelphia, Lippincott, 1968. 13 Spriggs, A. I., Chromosomes and Cancer, ed. J. German, p. 423. New York, John Wiley, 1974. 14 Kirkland, J. A., Stanley, M. A., and Cellier, K. M., Cancer (Philadelphia), 1967, 20, 1934. 15 Brandao, H. J. S., Acta Cytologica, 1969, 13, 232. 16 Wagner, D., Sprenger, E., and Blank, M. H., Acta Cytologica, 1972, 16, 2 3
517.
Illness in the Clouds The introduction of the Boeing 747-the current type of 400-passenger jumbo jet-has not really been as revolutionary as might be thought. The Boeing 707, originally designed for about 140 passengers, can and frequently does carry 190 passengers in and out of London's Heathrow, and the "stretched" D.C.8 now carries about 260 passengers.' What is new is the current economic climate in which the airlines can only operate profitably with large aircraft. In 1974 at Heathrow there are only nine airlines operating 747s but the number of 747 movements (arrivals and departures) was 18000 compared with 35 000 movements of 707s. In all, between April 1973 and April 1974 a total of 20 946 141 passengers used London's Heathrow Airport through 268 701 aircraft movements.
295
All travel tends to be exhausting, and at the airport lengthy check-in, security, and immigration procedures may cause anxiety before the passenger has even boarded, and the increasing size of the aircraft often means the passenger has a long walk weighed down with hand-baggage. Modern jet aircraft operate most efficiently at heights exceeding 35 000 ft (11 000 m). Though the cabins are pressurized the passenger is in effect exposed to an equivalent altitude2 of between 5000 and 7000 ft (2000 m). Healthy people have no difficulty in adapting their circulation to the resulting mild degree of hypoxia but anyone with cardiorespiratory disease may become distressed.3-5 Travel is expensive, so the mean age of air travellers is high; the elderly and middle-aged are prone to ischaemic heart disease and cerebrovascular disease, both of which may be adversely affected by hypoxia. An analysis of 471 voyage reports submitted by the cabin staff of B.O.A.C. showed that the most common illnesses were related to trauma: 94 incidents in all, including burns, scalds, sprains, and bruises. There were 15 reports of angina, 24 of heart failure, and 1 cardiac arrest with recovery; and 22 cases of dyspnoea, 5 of asthma, and 1 pulmonary embolus. There were 55 faints and 6 fits. Gastrointestinal disturbances were also common, as were E.N.T. problems; and there were 33 episodes of mental illness. There were four deaths. During the period of study there were over 7000 passengers known to be invalids who had sought the airline's medical department's help with their travels. Only 25 of the cases reported by the cabin staff were among those notified invalid passengers, though 2 of the deaths occurred in that group. Of 90 deaths from natural causes in passengers from 1947 to 1967 on B.O.A.C. ffights 34 were due to myocardial infarction, 6 to heart failure, 7 to cerebrovascular accidents, 13 to cancer, 3 to leukaemia, 3 to renal failure, 2 to pulmonary embolism, and 2 to cirrhosis of the liver. The remaining 20 deaths were due to other causes; 47 of the 90 deaths were in notified invalid passengers.4 In former days a flight to Australia took many days, with night stops in Rome, Beirut, Bombay, Calcutta, Bangkok, and Singapore. The modern stewardess is lucky if she gets a night stop in Glasgow, and much of the glamour of flying has gone. The stewardess and steward have a training in first aid and aviation medicine, but today few are already trained nurses. The medical supplies carried are designed for simple first aid procedures-sticking plaster and other dressings, antiseptic creams, insect repellant cream, paracetamol, and drugs for travel sickness and dyspepsia. British Airways aircraft also carry small stocks of barbiturates, morphine, nikethamide, antimalarials, and a mucus extractor. Most airlines operating jumbo jets employ 16 cabin staff on each ffight. Should a medical emergency occur and there are no medically trained staff or passengers available, the captain of the aircraft will usually have to divert to the nearest airport where medical assistance is at hand. Fortunately very few diversions are necessary, but with increasingly big aircraft coming into operation (there are already military aircraft capable of carrying 600 passengers) the risk of a medical emergency occurring increases. However, with larger numbers of passengers on each ffight there is also a higher statistical chance of there being a doctor in the house. Green, R. L., Association of Sea and Airport Health Authorities Annual Conference, 1972. Bergin, K., British Medical Journal, 1967, 3, 539. 3 Peffers, A. S. R., V International Conference of Diseases of the Chest, Tokyo, 1958. 4Richards, P. R., M.D. thesis, University of London, 1970. 5 Beighton, P. H., and Richards, P. R., British Heart Journal, 1968, 30, 367. 1
2
8 FEBRUARY 1975
possible feature would be the presence or absence of abnormal chromosome sets. Karyotype abnormalities have repeatedly been found in cervical lesions, including many lesions with surface maturation.'3 It has been suggested14 that the presence of abnormal mitoses in paraffin sections should be taken as a major feature for a new definition of carcinoma in situ, but that criterion would certainly be open to differences in interpretation. If the enlarged nuclei present in the mildest dysplasias turned out to be simply polyploid, with normal chromosome sets, and if that could be reliably determined, a tidy separation might be possible. Direct chromosome preparations are almost impossible to make from the lesions with low mitotic activity, but some of the evidence from Feulgen microspectrophotometry tends to support this concept.'5 16 Further careful studies on the nuclear DNA content in lesions considered to be on the borderline of cervical neoplasia would be illuminating and might even permit a separation into three-those with simple polyploidy, those with a scatter of aneuploid values, and those showing the emergence of a new dominant clone. Only the last could justifiably carry the question-begging name carcinoma in situ. If such a distinction could be shown (and there are formidable technical difficulties) we would still be left with the problem of discovering whether the newly-defined pathological states have different clinical courses when left untreated. Treated cases provide no information, since their risk of developing invasive cancer of the cervix is already known to be practically zero.
Koss, L. G., et al., Cancer (Philadelphia), 1963, 16, 1160. Johnson, L. D., Obstetrical & Gynecological Survey, 1969, 24, 735. Richart, R. M., Pathology Annual 1973, ed. S. C. Sommers. New York, Appleton-Century-Crofts., 1973, p. 301. 4Reagan, J. W., and Patten, S. F., Annals of the New York Academy of Sciences, 1962, 97, 662. 5 Patten, S. F., Diagnostic Cytology of the Uterine Cervix. Basle, Karger, 1969. 6 Thomas, D. B., American3Journal of Epidemiology, 1973, 98, 10. Thomas, D. B., and Anderson, R. I., American J'ournal of Epidemiology, 1974, 100, 113. 8 Bettinger, H. F., and Reagan, J. W., in Proceedings of the First International Congress on Exfoliative Cytology, ed. G. L. Wied. Philadelphia, Lippincott, 1962, p. 283. 9 Novak, E. R., and Woodruff, J. D., Novak's Gynecologic and Obstetric Pathology, 7th edn. Philadelphia, Saunders, 1974. 10 Govan, A. D. T., et ai.,3Journal of Clinical Pathology, 1969, 22, 383. 1 Riotton, G., and Christopherson, W. M., Cytology of the Female Genital Tract. Geneva, World Health Organization, 1973. 12 Koss, L. G., Diagnostic Cytology and its Histopathologic Bases, 2nd edn. Philadelphia, Lippincott, 1968. 13 Spriggs, A. I., Chromosomes and Cancer, ed. J. German, p. 423. New York, John Wiley, 1974. 14 Kirkland, J. A., Stanley, M. A., and Cellier, K. M., Cancer (Philadelphia), 1967, 20, 1934. 15 Brandao, H. J. S., Acta Cytologica, 1969, 13, 232. 16 Wagner, D., Sprenger, E., and Blank, M. H., Acta Cytologica, 1972, 16, 2 3
517.
Illness in the Clouds The introduction of the Boeing 747-the current type of 400-passenger jumbo jet-has not really been as revolutionary as might be thought. The Boeing 707, originally designed for about 140 passengers, can and frequently does carry 190 passengers in and out of London's Heathrow, and the "stretched" D.C.8 now carries about 260 passengers.' What is new is the current economic climate in which the airlines can only operate profitably with large aircraft. In 1974 at Heathrow there are only nine airlines operating 747s but the number of 747 movements (arrivals and departures) was 18000 compared with 35 000 movements of 707s. In all, between April 1973 and April 1974 a total of 20 946 141 passengers used London's Heathrow Airport through 268 701 aircraft movements.
295
All travel tends to be exhausting, and at the airport lengthy check-in, security, and immigration procedures may cause anxiety before the passenger has even boarded, and the increasing size of the aircraft often means the passenger has a long walk weighed down with hand-baggage. Modern jet aircraft operate most efficiently at heights exceeding 35 000 ft (11 000 m). Though the cabins are pressurized the passenger is in effect exposed to an equivalent altitude2 of between 5000 and 7000 ft (2000 m). Healthy people have no difficulty in adapting their circulation to the resulting mild degree of hypoxia but anyone with cardiorespiratory disease may become distressed.3-5 Travel is expensive, so the mean age of air travellers is high; the elderly and middle-aged are prone to ischaemic heart disease and cerebrovascular disease, both of which may be adversely affected by hypoxia. An analysis of 471 voyage reports submitted by the cabin staff of B.O.A.C. showed that the most common illnesses were related to trauma: 94 incidents in all, including burns, scalds, sprains, and bruises. There were 15 reports of angina, 24 of heart failure, and 1 cardiac arrest with recovery; and 22 cases of dyspnoea, 5 of asthma, and 1 pulmonary embolus. There were 55 faints and 6 fits. Gastrointestinal disturbances were also common, as were E.N.T. problems; and there were 33 episodes of mental illness. There were four deaths. During the period of study there were over 7000 passengers known to be invalids who had sought the airline's medical department's help with their travels. Only 25 of the cases reported by the cabin staff were among those notified invalid passengers, though 2 of the deaths occurred in that group. Of 90 deaths from natural causes in passengers from 1947 to 1967 on B.O.A.C. ffights 34 were due to myocardial infarction, 6 to heart failure, 7 to cerebrovascular accidents, 13 to cancer, 3 to leukaemia, 3 to renal failure, 2 to pulmonary embolism, and 2 to cirrhosis of the liver. The remaining 20 deaths were due to other causes; 47 of the 90 deaths were in notified invalid passengers.4 In former days a flight to Australia took many days, with night stops in Rome, Beirut, Bombay, Calcutta, Bangkok, and Singapore. The modern stewardess is lucky if she gets a night stop in Glasgow, and much of the glamour of flying has gone. The stewardess and steward have a training in first aid and aviation medicine, but today few are already trained nurses. The medical supplies carried are designed for simple first aid procedures-sticking plaster and other dressings, antiseptic creams, insect repellant cream, paracetamol, and drugs for travel sickness and dyspepsia. British Airways aircraft also carry small stocks of barbiturates, morphine, nikethamide, antimalarials, and a mucus extractor. Most airlines operating jumbo jets employ 16 cabin staff on each ffight. Should a medical emergency occur and there are no medically trained staff or passengers available, the captain of the aircraft will usually have to divert to the nearest airport where medical assistance is at hand. Fortunately very few diversions are necessary, but with increasingly big aircraft coming into operation (there are already military aircraft capable of carrying 600 passengers) the risk of a medical emergency occurring increases. However, with larger numbers of passengers on each ffight there is also a higher statistical chance of there being a doctor in the house. Green, R. L., Association of Sea and Airport Health Authorities Annual Conference, 1972. Bergin, K., British Medical Journal, 1967, 3, 539. 3 Peffers, A. S. R., V International Conference of Diseases of the Chest, Tokyo, 1958. 4Richards, P. R., M.D. thesis, University of London, 1970. 5 Beighton, P. H., and Richards, P. R., British Heart Journal, 1968, 30, 367. 1
2
