597 even
allowing for the large capital outlay on equipment.
favourably with some activities which are accepted without question as part of the acute hospital services-for example, the treatment of some forms of malignant disease by general surgeons, radiotherapists, and oncologists, which at best may result only in short-term palliation, which might be achieved more simply, and which at worst amounts to an expensive placebo. In contrast, the success of renal dialysis and transplantation, in terms of initial mortality, actuariallycorrected survival, and degree of rehabilitation achieved, is striking.12 The same is true for much open-
It compares very
heart surgery.
and hence to more effective use of specialists. They should concentrate on activities which only they can do; and they should be more willing to consider ways and means whereby some of the work currently regarded as their responsibility might be carried out by generalists. In the work which they retain within their units they should ensure that an appropriate proportion of their resources are reserved for effective procedures. This demands careful selection of patients, in accordance with agreed and declared policies. REFERENCES 1. Drake, C. G. J. Neurosurg 1978, 2. Hart, J. T. Lancet, 1971,i, 405.
13,14
49, 483.
(personal communication), cited by C. G. Drake in J. Neuro1978, 49, 483. 4. Hanlon, C. R. J. Neurosurg. 1978, 49, 785. 5. Editorial. Br. J. Radiol. 1975, 48, 517. 6. Thomas, M. L. Br. med. J. 1978,ii, 706 & 1225. 7. Gardner, R., Hanka, R., Evison, B., Mountford, P. M., O’Brien, V. C., Roberts, S. J. ibid. 1392. 8. McCarthy, M. Lancet, 1975,i, 1128. 9. Teasdale, G., Knill-Jones, R., Van der Sande, J. J. Neurol. Neurosurg. Psychiat. 1978, 41, 603 10. Jennett, B. Lancet, 1976, ii, 1235. 11. Jennett, B. in Clinical Practice and Economics (edited by C. I. Phillips and J. N. Wolfe); p. 46. London, 1977. 12. Morris, P. J., Bishop, M., Fellows, G., et al. Lancet, 1978,ii, 1353. 13. Ross, J. K., Monro, J. L., Manners, J. M., Edwards, J. C., Lewis, B., Hyde, I., Conway, N., Johnson, A. M. Br. med. J. 1976,ii, 1485. 14. Monro, J. L., Mollo, S., Brookbanks, S., Conway, N., Ross, J. K. ibid. 1978, 3. Ransohoff, J. surg.
CONCLUSIONS a fact of life in modern medicine in countries. It allows the development of effective methods of investigation and treatment, but the benefits of these techniques are seldom as widely available to appropriate patients as they might be. This is not only, or indeed mainly, due to lack of resources. A more serious hindrance is the reluctance of specialists to define their role, and to declare what they can and cannot do. Agreement between them and their colleagues in other disciplines could lead to more effective referral patterns,
Specialisation is
western
Hospital Practice CAN PATIENTS KEEP THEIR OWN PEAK-FLOW RECORDS RELIABLY? I. P. WILLIAMS M. R. HETZEL* R. M. SHAKESPEARE
Department of Thoracic Medicine, St. James’ Hospital, London SW12
Fifty patients recorded their peak expiratory-flow rate (P.E.F.R.) in hospital, unaided by nursing staff, five times a day for 5 days. Each patient’s readings were randomly and independently checked on two occasions during this period. 69% of checked readings were accurate. Most patients kept satisfactory records as a table, but were less efficient in recording their results on a P.E.F.R. chart. Recording of P.E.F.R. by patients with respiratory disease saves nursing time and provides valuable clinical information.
Summary
INTRODUCTION
Regular monitoring of peak expiratory-flow rate (P.E.F.R.)’ in respiratory disease is valuableespecially in severe asthma3where different patterns of response to treatment,4and high-risk groups,5 can be identified. In some general medical wards, however, routine P.E.F.R. monitoring by nursing staff is not feasible. We therefore investigated the reliability of P.E.F.R. records kept by patients themselves.
i, 1684.
disease, and ability to blow a P.E.F.R. of > 100 litres min"’on admission. Fifty suitable patients were recruited from consecutive admissions to our wards; although most had respiratory disease, this was not a prerequisite for inclusion. There was no age limit. Each patient used the same miniature Wright peak-flow meter6 throughout the study and made recordings at 4-hourly intervals between 6 A.M. and 10 P.M. for the first 5 consecutive days of admission. Those patients who were treated with bronchodilator drugs took them 30 min after the times appointed for P.E.F.R. measurement. On each occasion, 3 readings were taken and recorded on a simple table with the date and time. Patients were asked to plot the highest of these 3 readings on a standard P.E.F.R. chart printed with gradations for the day and time on the x axis and a P.E.F.R. scale in 20 litres min-l increments on the y axis. On admission these procedures and the use of the meter were demonstrated by the, first observer who then supervised the first 2 sets of readings. Patients were then left to keep their own tables and charts. On two randomly selected occasions during the 4th and 5th days the second observer, who was not involved in patients’ management or allowed to see their records, visited patients 10 min after they should have made a recording and asked them to blow a further three peak flows into their own meters. Patients were not warned that they would be checked and the observer attempted to reduce their awareness of the purpose of his visit by memorising his check readings and recording them after leaving the patient. Means of the three readings for each set of doctor and patient results were compared. The total number of readings which patients recorded in their tables and the number and accuracy of readings which patients transferred from their tables to the P.E.F.R. charts were assessed; a reading was regarded as being accurately recorded if it was plotted within +20 litres min-of its correct position on the chart. RESULTS
PATIENTS AND METHODS
Criteria for inclusion in the study were literacy, eyesight good enough to read the meter scale, absence of psychiatric *Present address:
Brompton Hospital,
Fulham
Road., London SW3.
Patients’ mean age was 54.8years (range 13-89 There were thirty-five men and fifteen women. Clinical diagnoses on admission were asthma (ten), chronic bronchitis (fourteen), other respiratory disease
years).
598 a few readings can be omitted since it is the overall pattern of results which is important. We consider a range of + 101’c in the concordance of doctor and patient results acceptable in clinical practice; particularly at lower peak flows where the mini-meter’s own mechanical repeatability error’ of ±10 litres min-1may have had some effect on accuracy. 8YI; (forty-one) of our fifty patients attempted over 71r of the twenty-five possible readings and 691( of those readings which could be checked were of acceptable accuracy. This implies that most patients could produce tabulated results with a clinical value comparable to that of records made by
is not essential and
nurses.
their failure was to plot only a proportion of results from the table, but these were done accurately. The principal problem may therefore have been that of insufficient motivation to plot results graphically. The nine patients who did not plot any of their results on the chart were significantly older, and were probably less familiar with the mathematical concept of graphs, than those patients who plotted some results. A table of numerical results can, however, be quickly scanned to determine the dominant trend. We therefore suggest that, particularly for older patients, a simple table for results would be more efficient than charts. The main problem in this study was the validation of a sufficient number of patients’ readings by an independant observer without making patients more conscientious than they would have been without supervision. We compromised with two blind check readings by the second observer and deliberately avoided encouraging patients to continue their records. Patient compliance might well improve with encouragement. P.E.F.R. monitoring is of most value in asthmatic patients. Had we studied only asthmatic patients, spontaneous changes in bronchomotor tone in the 10 mm interval between patients’ and doctor’s readings would have introduced discrepancies. Bronchodilator drugs were avoided during this interval for the same reason. Inclusion of patients with other respiratory conditions, whose readings should be more stable, has, we hope, reduced this effect. Recruitment of patients with nonrespiratory diseases allowed results at high P.E.F.R.S to be checked. Furthermore, some asthma patients must have been familiar with the peak-flow meter before the study and assessment of subjects who had never used it before seems a better test. Patients with a P,E.F.R. < 100 litres min-’ were excluded because smallartations in P.E.F.R. could cause relatively large percentage errors at this level. We conclude that patient self-monitored P.E.F.R. IS practicable in general medical wards. In addition to providing essential information without taking up nursing time, this method also trains asthma patients so that they can subsequently keep P.E.F.R. records at home with further benefits to their management as outpatients
Graphic representation of results by patients
P.E.F.R.
Patients’
own readings of P.E.F.R. compared readings 10 min later. Solid line indicates identity ; dotted lines +10.
(nine), cardiovascular conditions (six).
disease
(eleven),
with observer’s
and non-thoracic
Accuracy of Checked Readings Readings from thirty-four patients could be checked on both occasions. A further nine patients had, however, failed
to
make their
own
records for
one
of the times
on
which
they were checked and the remaining seven patients had failed to record their peak flow at the appointed time on both occasions that the second observer checked their readings. Thus at least one reading was available for forty-three patients, and seventyseven patient readings could be checked. For fifty-three of these seventy-seven patient readings (69%) the doctor’s and patient’s results were within 10% of each other (see accompanying figure). Comparison of Records in a Table and on P.E.F.R. Chart
Forty-one of the fifty patients attempted over 71% of the possible twenty-five sets of readings and recorded their results in their tables. Of these forty-one patients, thirty-one plotted over 71% of the results in their tables on their P.E.F.R. charts. Their results were transferred from table to chart with a mean 95% of readings accu-
rately plotted (range 53-100%).
Ten patients plotted less than 71% of results, but the accuracy of the few results which they plotted was, nevertheless, high. Nine patients did not attempt to plot any of their results on the P.E.F.R. chart, although seven of them had attempted over 71% of the possible recordings in their tables. The mean age of these nine patients (69 years) than that of the other was significantly higher (P
allowing for the large capital outlay on equipment.
favourably with some activities which are accepted without question as part of the acute hospital services-for example, the treatment of some forms of malignant disease by general surgeons, radiotherapists, and oncologists, which at best may result only in short-term palliation, which might be achieved more simply, and which at worst amounts to an expensive placebo. In contrast, the success of renal dialysis and transplantation, in terms of initial mortality, actuariallycorrected survival, and degree of rehabilitation achieved, is striking.12 The same is true for much open-
It compares very
heart surgery.
and hence to more effective use of specialists. They should concentrate on activities which only they can do; and they should be more willing to consider ways and means whereby some of the work currently regarded as their responsibility might be carried out by generalists. In the work which they retain within their units they should ensure that an appropriate proportion of their resources are reserved for effective procedures. This demands careful selection of patients, in accordance with agreed and declared policies. REFERENCES 1. Drake, C. G. J. Neurosurg 1978, 2. Hart, J. T. Lancet, 1971,i, 405.
13,14
49, 483.
(personal communication), cited by C. G. Drake in J. Neuro1978, 49, 483. 4. Hanlon, C. R. J. Neurosurg. 1978, 49, 785. 5. Editorial. Br. J. Radiol. 1975, 48, 517. 6. Thomas, M. L. Br. med. J. 1978,ii, 706 & 1225. 7. Gardner, R., Hanka, R., Evison, B., Mountford, P. M., O’Brien, V. C., Roberts, S. J. ibid. 1392. 8. McCarthy, M. Lancet, 1975,i, 1128. 9. Teasdale, G., Knill-Jones, R., Van der Sande, J. J. Neurol. Neurosurg. Psychiat. 1978, 41, 603 10. Jennett, B. Lancet, 1976, ii, 1235. 11. Jennett, B. in Clinical Practice and Economics (edited by C. I. Phillips and J. N. Wolfe); p. 46. London, 1977. 12. Morris, P. J., Bishop, M., Fellows, G., et al. Lancet, 1978,ii, 1353. 13. Ross, J. K., Monro, J. L., Manners, J. M., Edwards, J. C., Lewis, B., Hyde, I., Conway, N., Johnson, A. M. Br. med. J. 1976,ii, 1485. 14. Monro, J. L., Mollo, S., Brookbanks, S., Conway, N., Ross, J. K. ibid. 1978, 3. Ransohoff, J. surg.
CONCLUSIONS a fact of life in modern medicine in countries. It allows the development of effective methods of investigation and treatment, but the benefits of these techniques are seldom as widely available to appropriate patients as they might be. This is not only, or indeed mainly, due to lack of resources. A more serious hindrance is the reluctance of specialists to define their role, and to declare what they can and cannot do. Agreement between them and their colleagues in other disciplines could lead to more effective referral patterns,
Specialisation is
western
Hospital Practice CAN PATIENTS KEEP THEIR OWN PEAK-FLOW RECORDS RELIABLY? I. P. WILLIAMS M. R. HETZEL* R. M. SHAKESPEARE
Department of Thoracic Medicine, St. James’ Hospital, London SW12
Fifty patients recorded their peak expiratory-flow rate (P.E.F.R.) in hospital, unaided by nursing staff, five times a day for 5 days. Each patient’s readings were randomly and independently checked on two occasions during this period. 69% of checked readings were accurate. Most patients kept satisfactory records as a table, but were less efficient in recording their results on a P.E.F.R. chart. Recording of P.E.F.R. by patients with respiratory disease saves nursing time and provides valuable clinical information.
Summary
INTRODUCTION
Regular monitoring of peak expiratory-flow rate (P.E.F.R.)’ in respiratory disease is valuableespecially in severe asthma3where different patterns of response to treatment,4and high-risk groups,5 can be identified. In some general medical wards, however, routine P.E.F.R. monitoring by nursing staff is not feasible. We therefore investigated the reliability of P.E.F.R. records kept by patients themselves.
i, 1684.
disease, and ability to blow a P.E.F.R. of > 100 litres min"’on admission. Fifty suitable patients were recruited from consecutive admissions to our wards; although most had respiratory disease, this was not a prerequisite for inclusion. There was no age limit. Each patient used the same miniature Wright peak-flow meter6 throughout the study and made recordings at 4-hourly intervals between 6 A.M. and 10 P.M. for the first 5 consecutive days of admission. Those patients who were treated with bronchodilator drugs took them 30 min after the times appointed for P.E.F.R. measurement. On each occasion, 3 readings were taken and recorded on a simple table with the date and time. Patients were asked to plot the highest of these 3 readings on a standard P.E.F.R. chart printed with gradations for the day and time on the x axis and a P.E.F.R. scale in 20 litres min-l increments on the y axis. On admission these procedures and the use of the meter were demonstrated by the, first observer who then supervised the first 2 sets of readings. Patients were then left to keep their own tables and charts. On two randomly selected occasions during the 4th and 5th days the second observer, who was not involved in patients’ management or allowed to see their records, visited patients 10 min after they should have made a recording and asked them to blow a further three peak flows into their own meters. Patients were not warned that they would be checked and the observer attempted to reduce their awareness of the purpose of his visit by memorising his check readings and recording them after leaving the patient. Means of the three readings for each set of doctor and patient results were compared. The total number of readings which patients recorded in their tables and the number and accuracy of readings which patients transferred from their tables to the P.E.F.R. charts were assessed; a reading was regarded as being accurately recorded if it was plotted within +20 litres min-of its correct position on the chart. RESULTS
PATIENTS AND METHODS
Criteria for inclusion in the study were literacy, eyesight good enough to read the meter scale, absence of psychiatric *Present address:
Brompton Hospital,
Fulham
Road., London SW3.
Patients’ mean age was 54.8years (range 13-89 There were thirty-five men and fifteen women. Clinical diagnoses on admission were asthma (ten), chronic bronchitis (fourteen), other respiratory disease
years).
598 a few readings can be omitted since it is the overall pattern of results which is important. We consider a range of + 101’c in the concordance of doctor and patient results acceptable in clinical practice; particularly at lower peak flows where the mini-meter’s own mechanical repeatability error’ of ±10 litres min-1may have had some effect on accuracy. 8YI; (forty-one) of our fifty patients attempted over 71r of the twenty-five possible readings and 691( of those readings which could be checked were of acceptable accuracy. This implies that most patients could produce tabulated results with a clinical value comparable to that of records made by
is not essential and
nurses.
their failure was to plot only a proportion of results from the table, but these were done accurately. The principal problem may therefore have been that of insufficient motivation to plot results graphically. The nine patients who did not plot any of their results on the chart were significantly older, and were probably less familiar with the mathematical concept of graphs, than those patients who plotted some results. A table of numerical results can, however, be quickly scanned to determine the dominant trend. We therefore suggest that, particularly for older patients, a simple table for results would be more efficient than charts. The main problem in this study was the validation of a sufficient number of patients’ readings by an independant observer without making patients more conscientious than they would have been without supervision. We compromised with two blind check readings by the second observer and deliberately avoided encouraging patients to continue their records. Patient compliance might well improve with encouragement. P.E.F.R. monitoring is of most value in asthmatic patients. Had we studied only asthmatic patients, spontaneous changes in bronchomotor tone in the 10 mm interval between patients’ and doctor’s readings would have introduced discrepancies. Bronchodilator drugs were avoided during this interval for the same reason. Inclusion of patients with other respiratory conditions, whose readings should be more stable, has, we hope, reduced this effect. Recruitment of patients with nonrespiratory diseases allowed results at high P.E.F.R.S to be checked. Furthermore, some asthma patients must have been familiar with the peak-flow meter before the study and assessment of subjects who had never used it before seems a better test. Patients with a P,E.F.R. < 100 litres min-’ were excluded because smallartations in P.E.F.R. could cause relatively large percentage errors at this level. We conclude that patient self-monitored P.E.F.R. IS practicable in general medical wards. In addition to providing essential information without taking up nursing time, this method also trains asthma patients so that they can subsequently keep P.E.F.R. records at home with further benefits to their management as outpatients
Graphic representation of results by patients
P.E.F.R.
Patients’
own readings of P.E.F.R. compared readings 10 min later. Solid line indicates identity ; dotted lines +10.
(nine), cardiovascular conditions (six).
disease
(eleven),
with observer’s
and non-thoracic
Accuracy of Checked Readings Readings from thirty-four patients could be checked on both occasions. A further nine patients had, however, failed
to
make their
own
records for
one
of the times
on
which
they were checked and the remaining seven patients had failed to record their peak flow at the appointed time on both occasions that the second observer checked their readings. Thus at least one reading was available for forty-three patients, and seventyseven patient readings could be checked. For fifty-three of these seventy-seven patient readings (69%) the doctor’s and patient’s results were within 10% of each other (see accompanying figure). Comparison of Records in a Table and on P.E.F.R. Chart
Forty-one of the fifty patients attempted over 71% of the possible twenty-five sets of readings and recorded their results in their tables. Of these forty-one patients, thirty-one plotted over 71% of the results in their tables on their P.E.F.R. charts. Their results were transferred from table to chart with a mean 95% of readings accu-
rately plotted (range 53-100%).
Ten patients plotted less than 71% of results, but the accuracy of the few results which they plotted was, nevertheless, high. Nine patients did not attempt to plot any of their results on the P.E.F.R. chart, although seven of them had attempted over 71% of the possible recordings in their tables. The mean age of these nine patients (69 years) than that of the other was significantly higher (P
