James Connolly Memorial Hospital,. Blanchardstown,. Dublin 15,. Republic of Ireland. I Homer AC, Gilleard C. Abuse of elderly people by their carers. BMJ 1990 ...
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Funding research into alternative animal procedures SIR,-As chairman of the research subcommittee of the Animal Procedures Committee I am pleased to announce that limited funds will be available from April for research in the United Kingdom into the reduction, refinement, or replacement of the use of living animals in scientific procedures. The use of living animals in scientific procedures is an emotive issue that raises several ethical questions. There is considerable public awareness and concern about the purposes of many procedures and how they are carried out and this is often heightened by misleading reporting. The fact remains, however, that regrettably the use of animals continues to be needed in many areas of research work and safety testing. It is of course incumbent upon those working in biomedical research to ensure that they use animals only where -no suitable alternative exists, that they use the minimum number of animals necessary, and that no avoidable suffering is caused. These principles are enshrined in the Animals (Scientific Procedures) Act 1986, which imposes strict controls on the use of living animals in scientific procedures. Much work is already being done by charitable bodies and commercial concerns to find alternatives to the use of living animals. But it is important that those involved in research work and safety testing are seen to be seeking alternatives. The Animal Procedures Committee will give preference to research proposals which have a good prospect of leading to the refinement or replacement of procedures that use large numbers of animals or that entail substantial suffering-for example, challenge tests and vaccine production. The committee also continues to be interested in the possibility of developing better measures of disease, discomfort, and stress in laboratory animals and in improvements in the husbandry of such animals. Grants will normally be awarded for periods up to three years. Details of the research scheme and how to apply may be obtained from Mr Peter Edmundson, E Division, Room 971, Home Office, 50 Queen Anne's Gate, London SW1H 9AT (071 273 2029). Completed applications will be considered in the first half of April this year. SIR ANDREW HUXLEY Animal Procedures Committee, London SW I H 9AT
abusing their elderly relatives. ' The authors emphasised the willingness of these carers to discuss their behaviour, given the right circumstances. The paper did not, however, discuss a group of abusing carers, probably a minority, who abuse their elderly relatives for gain or gratification. Such carers may perpetrate quite horrific abuse of their relatives, who generally are unable to draw attention to their plight because offear or mental or physical frailty. The following case history illustrates this form of abuse. A widow in her 80s was referred to the accident and emergency department of a large general hospital because neighbours reported that she frequently cried during the night and they had noticed bruising. Abuse was suspected by the hospital and a social worker involved, who despite her best efforts was unable to assist directly, but she initiated referral to the old age psychiatry service. The woman was found to be severely cognitively impaired as a consequence of dementia and so was unable to give a history, but she was obviously very distressed and frightened and bruising was apparent. On further investigation it transpired that she was being both physically and sexually abused by her alcoholic son. He also took her pension to buy alcohol. After informal discussion with the director of community care arrangements were made for this woman to move into residential care, where she settled well. Her son was .initially reluctant to let her move and only his fear of being charged with offences against his mother led to him finally agreeing. If he had persisted in his refusal it is doubtful whether evidence of the offences could have been satisfactorily produced for a court, and certainly recourse to the courts would have delayed matters. In these cases the abusing carer may be described as pathological as factors within the abuser are the sole determinants ofviolence. In the case described alcohol abuse was obviously relevant; other examples of such factors include sociopathic behaviour, mental retardation, and psychiatric disorders such as schizophrenia. In managing these cases an essential prerequisite is that professional staff are alert to this form of abuse. In addition, there is also a need for specific legislation. A statutory procedure similar to that used in child abuse cases would be a possible mechanism.' Essential components would include legal procedures both to gain access to the elderly victim and to remove him or her to a place of safety. MARGO WRIGLEY
Abuse of elderly people by their carers SIR,-In the study by Drs Ann C Homer and C Gilleard an astonishing 45% of carers admitted to
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James Connolly Memorial Hospital, Blanchardstown, Dublin 15, Republic of Ireland I Homer AC, Gilleard C. Abuse of elderly people by their carers.
BMJ 1990;301:1359-62. (15 December.) 2 DepartmentofHealth. Child abuse guide-lines. Dublin: Stationery Office, 1987.
Tomography in deep vein thrombosis SIR,-Dr J M Schindler and colleagues conclude that colour coded duplex ultrasonography has sensitivity and specificity of 100% in the diagnosis of acute deep vein thrombosis of the leg.' This concurs with the findings of other groups.23 Unfortunately, these figures apply only to the femoral and popliteal veins; indeed, the authors state that the calf veins were not investigated. Studies at necropsy4 and using phlebography5 and scintigraphy6 indicate that most deep vein thrombuses occur or originate in the calf veins. Assessment of any diagnostic test for deep vein thrombosis must therefore address the problem of detecting thrombuses in the calf veins. Duplex studies that have included imaging of the calf veins indicate that the sensitivity of the investigation in this region is 73-84% and that the specificity is 86-92%.23 The excellent results of duplex scanning in detecting deep vein thrombosis above the knee cannot be extrapolated to the greater problem of detecting calf vein thrombosis. NICHOLAS M WILSON KEVIN G BURNAND
Division of Surgery, St Thomas's Hospital, London SE1 7EH I Schindler JM, Kaiser M, Gerber A, Vuilliomenet A, Popovic A, Bertel 0. Colour coded duplex sonography in suspected deep vein thrombosis of the leg. BMJ 1990;301:1369-70. (15
December.) 2 Rose SC, Zwiebel WJ, Nelson BD, et al. Symptomatic lower extremity deep venous thrombosis: accuracy, limitations, and role of color duplex flow imaging in diagnosis. Radiology
1990;175:639-44. 3 Lee B, Thomas ML, Bumand KG, Browse NL. Comparative trial of ascending phlebography versus duplex ultrasonography in the diagnosis of deep venous thrombosis. Br J Surg 1990;77:A701. 4 Gibbs NM. Venous thrombosis in the lower limbs with particular reference of bedrest. BrJ7 Surg 1957;45:209-36. 5 Nicolaides AN, Kakkar VV, Field ES, Renney JTG. The origin of deep vein thrombosis: a venographic study. Br J Radiol 1971;44:653-63. 6 Flanc C, Kakkar VV, Clarke MB. The detection of venous thrombosis of the legs using "I labelled fibrinogen. BrJ Surg 1968;55:742-7.
SIR,-The omission of any assessment of the calf veins in the study of colour coded duplex sonography in the diagnosis of deep vein thrombosis by Dr J M Schindler and colleagues' weakens the case for using duplex sonography as the only diagnostic test for venous thrombosis. We prospectively studied 58 patients (60 limbs) with clinically suspected deep vein thrombosis using colour duplex sonography and ascending venography. Our results (table) would confirm the accuracy of duplex sonography in the diagnosis of
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Results of using colour duplex sonography in 58 patients (60 limbs) with clinically suspected deep vein thrombosis Location of thrombus Axial and calf veins Axial vein Calf vein Diagnostic criteria: Intraluminal filling defect Occlusion Compressibility Augmentation of flow Echogenicity
No false positive 0 0 0
axial vein thombuses, but this technique still fails to identify 30% of calf vein thrombuses.2 Thrombuses in the calf veins are usually the earliest and most frequent manifestation of deep vein thombosis. Although axial vein involvement may result from propagation of such thrombuses, isolated calf vein thombuses remain an important cause of pulmonary embolism and the postthrombotic limb syndrome.3 To date phlebography remains the only reliable and accurate investigation for the diagnosis of such thrombuses. Colour coded duplex sonography can accurately diagnose axial vein thrombosis. It may therefore have a role as a first line investigation in patients suspected of having a deep vein thrombosis. A negative result, however, must be followed up by phlebography to assess the calf vein system fully. It is possible that with all of these diagnostic criteria serial duplex scanning may improve the diagnostic yield, particularly of calf vein thrombuses. Currently reported experience with duplex sonography and deep vein thrombosis supports its continued use as a preliminary investigation, but until the diagnosis of calf vein thrombosis improves we continue to advocate combined sonography and phlebography in any patient clinically suspected of having a deep vein thrombosis. SAROJ K DAS NOEL V WILSON VIJAY V KAKKAR Thrombosis Research Institute, King's College Hospital, London SE5 8RX I Schindler JM, Kaiser M, Gerber A, Vuilliomenet A, Poposic A, Bertel 0. Colour coded duplex sonographv in suspected deep vein thrombosis of the leg. BAJ 1990;301:1369-70. (15
December.) 2 Das SK, Kakkar VV. Colour coded duplex sonographv as a replacement for senography in the diagnosis of acute deep vein thrombosis. Brj Surg 1990;77:1424-5. 3 Kakkar VV, Flanc C, Howe Cl, Clarke MB. Natural history of postoperative deep vein thrombosis. Lancet 1969;ii:230-3.
SIR,-We performed a comparative study of over 200 patients with conventional duplex ultrasonography and phlebography in this department and agree with Dr J M Schindler and colleagues' that the best diagnostic criterion is incompressibility, as emphasised in this and many other papers.23 In the presence of ileofemoral thrombosis the diagnosis may be virtually instantaneous.4 Other criteria are complementary to this finding, as is the use of either duplex or colour Doppler ultrasound equipment. Considerable experience is necessary for a confident diagnosis with this technique, and our experience to date has been that the patient with a negative diagnosis on ultrasonography will still require phlebography. Our experience of duplex Doppler ultrasonography indicates that it is valuable in assessing the presence or absence of pelvic thrombus and in distinguishing communicating from non-communicating thrombus. The upper margin of a free floating thrombus can often be shown by direct imaging alone. The routine demonstration of isolated calf thrombus by ultrasonography is difficult, time consuming, and often unreliable, although other significant pathology such as a calf haematoma
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No false negative
Salmeterol in nocturnal asthma
SIR,-Dr M F Fitzpatrick and colleagues have gone to great lengths to produce a carefully con79 6 100 trolled objective study,' but we have some 87 2 100 reservations about the conclusion that inhaled 69 4 100 salmeterol improves objective sleep quality in patients with nocturnal asthma. 50 96 85 86 This conclusion is based on an improved type 96 66 0-1 and type 4 sleep in the group of patients given 60 96 50 tg salmeterol compared with the placebo group, 50 95 but this group of patients did not have significantly better sleep overall (sleep efficienLy was not may be readily identified. Treatment with anti- statistically significant), did not spend a signicoagulant drugs has been the subject of consider- ficantly shorter period awake at night, and did not able previous debate,5 but most clinicians will want have a reduced use of rescue salbutamol. The a definite answer at the time of presentation. The significant difference in total wakefulness after accuracy of colour Doppler ultrasonography in sleep onset is likely to be explained by the treatment identifying calf thrombus is not yet definitively group taking a longer time initially to go to sleep. established,67 and it seems that technical factors as This would fit with the authors' proposals that well as expertise influence the diagnosis. It seems salmeterol has some properties of a central nervous unlikely that most colour duplex examinations system stimulant. Most importantly, the patients can be performed at the bedside: the equipment themselves could detect no difference in their is extremely cumbersome and, like the hippo- quality of the sleep, and the authors have not potamus, prone to nervous shock.8 Again, the cost attempted to show improved daytime cognitive of such equipment exceeds that of conventional function with these borderline improvements in equipment, even with duplex facilities, by a factor objective sleep quality. of at least two. It is not yet widely available in Furthermore, it is difficult to see why patients British district hospitals, and the argument for given 50 ig salmeterol were deemed to have a such expensive equipment in district departments better night than the group given 100 ig: their remains to be established. sleep efficiency was no different, they did not We agree that compression ultrasonography is a spend less time awake at night, they used more highly accurate and simple non-invasive method rescue salbutamol than the 100 [tg group, and the for detecting proximal thrombosis and for exclud- number of nocturnal awakenings a night was ing other causes of limb pain and swelling (which 'identical. In fact, we are not told if there was a may occur in up to 15% of cases9), but contrast significant difference between these two groups for phlebography is still necessary when there is a type 0-1 and type 4 sleep. negative diagnosis on ultrasonography. A comRegarding the statistical methods: two (10%) of pression ultrasound examination can be performed the patients dropped out of the trial, and data from with equipment widely available in British a third patient were only partly complete because hospitals and should be the initial diagnostic he died while in the treatment arm of the study; modality used in a patient with a clinical diagnosis also, figures 1 and 2 and table II show quite clearly of deep vein thrombosis. that the magnitude of the differences between We now routinely perform an initial ultrasound groups is small and the ranges large. Although examination followed by contrast phlebography if statistically significant, these differences are not the result of the ultrasound examination is negative. necessarily clinically important. The graphic data This is a rapid and cost effective approach and are presented as the mean and standard error of the promises to eliminate the need for phlebography in mean whereas the tabular data are presented as the up to a third of patients in whom deep vein median and range (appropriate for non-parametric thrombosis of the lower limb has been diagnosed data such as this). If the graphic data were clinically, in addition to identifying and avoiding presented as they should be the differences inappropriate treatment with anticoagulant drugs between groups would become less apparent. in patients with other causes for their symptoms. In conclusion, the data do not show that there is an objective improvement in sleep quality in C H WRIGHT asthmatic patients taking salmeterol. Rather, they D J WIDDOWSON would seem to suggest that reduced nocturnal C A McCONNELL rescue with salbutamol (the final determinant of R A BYRNE the patient's subjective sense of wellbeing during H G ROW the night) and improved sleep quality are mutually S J HOTSTON Glan Clwyd Hospital, exclusive events while either 50 .tg or 100 itg of Rhyl, inhaled salmeterol is being taken twice daily. Clwyd LL18 5UJ
Specificity (%)
Sensitivity (%)
1 Schindler JM, Kaiser M, Gerber A, Vuilliomenet A, Popovic A, Bertel 0. Colour coded duplex sonography in suspected deep vein thrombosis of the leg. BMJ 1990;301:1369-70. (15 December.) 2 Effeney DJ, Freidman MB, Gooding GAW. Ileofemoral venous thrombosis: real time ultrasound diagnosis, normal criteria and clinical applications. Radiology 1984;150:787-92. 3 Whitehouse GH. Venous thrombosis and thromboembolism. Clin Radiol 1990;41:77-80. 4 Aitken AGF, Godden DJ. Real time ultrasound diagnosis of deep vein thrombosis: a comparison with venography. Clin Radiol 1987;38:309-13. 5 Salzman EW. Venous thrombosis made easy. N Engl J Med
S SARIN S SHAMI T CHEATLE
Department of Surgerv, Middlesex Hospital, London WIIN 8AA I Fitzpatrick MF, Mackay T, Driver H, Douglas NJ. Salmeterol in nocturnal asthma: a double blind, placebo controlled trial of a long acting inhaled IP2 agonist. BMJ 1990;301: 1365-8. 1 5 December.)
1986;315:847-8. 6 Baxter GM, McKechnie S, Duffy P. Colour doppler ultrasound in deep venous thrombosis: a comparison with venography.
Clin Radiol 1990;42:32-6. 7 Rose SC, Zweibel WJ, Nelson BD, et al. Symptomatic lower extremity deep venous thrombosis: accuracy, limitations, and role of colour duplex flow imaging in diagnosis. Radiologv 1990;175:639-44. 8 Eliot TS. The hippopotamus. In: Poems 1909-25. London: Faber and Faber, 1925:61. 9 White RH, McGahan P, Daschbach MM, Hartling RP. Diagnosis of deep vein thrombosis using duplex ultrasound. Ann Intern Med 1989;111:297-304.
AUTHORS' REPLY,-We showed statistically significant improvements in the objective sleep quality of patients with nocturnal asthma when they were taking inhaled salmeterol 50 Ftg twice daily-a mean 26% reduction in time spent awake or drowsy at night and a mean 30% increase in time spent in stage 4 (deep) sleep-as compared with placebo. Contrary to the speculation of Mr Sarin and colleagues, we found no significant difference
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