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Ergonomic aspects of equipment
Inf. J. Nun. Slud., Vol. 24. No. 4. pp. Printed in Great Britain.
331-337,
0020-7489/87 $3.00+0.00 Pergamon Journals Ltd.
1987
Ergonomic aspects of equipment F. BELL, B.Sc., Ph.D., C.Eng., M.1.Mech.E. Department of Physiotherapy, Queen Margaret College, Clerwood Terrace, Edinburgh EH12 8TS, U.K.
Abstract-Mechanical patient-lifting devices have been available for hospital use for at least the past 100 yr. Mobile hoists have been available since the 1950s and the most common U.K. hospital mobile hoist, the Mecanaids’ Ambulift, has been available since 1966. Recent investigations have confirmed that these devices are not being used to any significant extent to ease most of the patientlifting problems in hospital wards. Attention to four variables, the patient, the attendant, the task and the environment, is essential in determining the right systematic approach to equipment design and selection.
Introduction
Between the mid-1950’s and the mid-1960’s a variety of commercially available hoists were introduced in the United Kingdom to assist in the lifting and movement of physically disabled people. By the late 1960’s it was generally recognized that many of these devices, purchased by hospitals, were simply not being used and were ‘gathering cobwebs’ in cupboards (Norton, 1970). The need for research, evaluation and information on hoists became a focal point for those concerned with aids in the early 1970’s with particular studies being initiated in London (Tarling, 1980), Oxford (Wilshere et al., 1972), Edinburgh (Hoyland, 1973) and Sweden (Palmkvist and Feeney, 1973; Kube, 1976). The Department of Health and Social Security (DHSS) initiated the establishment of standards for the mechanical safety of mobile patient lifters with the British Standards Institution (BSI, 1979). Between 1977 and 1981 the author undertook a specific investigation of the utilization of mobile hoists in hospital in the United Kingdom, funded by the DHSS (Bell et al., 1979a,b; Bell 1979, 1984; Bell and Fennell, 1980). This study revealed that hoists were still not being used to any significant extent to ease most of the patient-lifting problems in hospital wards with perhaps the exception of the bathing task. A brief review of developments in this field during the past century and an outline of the complexity of the problems facing nursing staff may help guide would-be design innovators to gain a perspective of the apparent problems, a necessary first step in tackling possible solutions. For illustrations of the materials described below the reader is referred to Bell (1984). 14 Controller
HMSO
1987. 331
332
F. BELL
Patient-lifters
reviewed
Aids for patients and nurses Aids can be designed to be used either by the patient or by the attendant, i.e. the nurse. For any particular task, whether associated with treatment or personal care, the amount of physical assistance that the patient requires will depend upon his physical and mental capability and his liability; it may be dangerous to allow the patient to exert physical effort even if he is physically able to do so. Simple aids that are available for patients to use today include overhead trapezes, rope ladders, hand blocks, sliding boards, grab rails, bath seats and raised toilet seats. Aids for nursing include adaptations for draw sheets, lifting cushions and levers (e.g. the LIC lifting cushions and Nesbit-Evans Mini-Paroll). Identifying the task and the intended user of an aid are obviously primary criteria in designing an aid. Lifting tasks and clinical management The proportion of elderly patients in the hospital population has been increasing over the past century and this in itself has changed the nature of patient-lifting problems. However, equally important are changes which have occurred in the general clinical management of patients. In the mid-1950’s more emphasis was placed on mobilizing patients at an earlier stage in their care to prevent complications to which the bedfast are prone, such as deep-vein thrombosis and pressure sores. Assisting the movement of the bedfast patient is still a problem today but the earlier ambulation of patients now extends attention to other tasks outwith the bed; patient transfer in and out of bed, in and out of chairs, on and off toilets and, of particular interest to designers for the past 30 yr or so, in and out of baths. Prior to the mid-1950’s, however, the problem of dealing with the bedfast patient apparently attracted most endeavour from inventors and led to a number of almost identical patient-lifting devices. A 19th century catalogue of J. & A. Carters Ltd seen by the author illustrated an ‘invalid lift’ which can be dated to 1880 by the ‘testimonials’ included in the advertisement. A review of the literature reveals at least six similar devices (Maddox, 1939; Jeanmaire, 1940; Lagergren, 1945; Gubbins, 1947; Ebbinghaus, 1952; and Hunt, 1954) each apparently independently invented between 1939 and 1954. All of these devices used a manually operated mechanism to raise the patient’s body, partly or totally, from the mattress. An externally powered patient-lifting device was described by Kostrubala and Wagner in an article in 1948. This was a fixed-point, electrically operated hoist, used to facilitate the changing of patients’ wound dressings. All of these devices were still essentially concerned only with raising or repositioning the patient. For the patient to leave the confines of the bed, the design criteria had to be extended or changed and new problems appeared. Transfer to and from the bed Transferring or transporting the recumbent patient between his bed and, say, the operating theatre or another hospital department, is a common task today and must have been a common task in the past also. Manual lifting combined with the use of stretchers and trolleys would have been the simplest method and this is best achieved with the patient on a relatively high bed platform. In addition, nursing and medical procedures for the bedfast patient are more easily undertaken if the bed mattress is at a working bench height. The device described by Gubbins (1947) was commercially available as the Cullen Hospital Crane up
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until 1977 and one model incorporated castors to allow transportation of the recumbent patient. Today some of the most sophisticated patient-handling systems are available for transferring the recumbent patient to and from operating theatres. However, mobilizing the ambulent, semi-ambulant or chair-fast patient within the hospital ward presents quite different problems associated with conflicting needs. Beds and chairs
A high hospital bed which can be an advantage to nursing and medical staff when dealing with a patient, can present a potential hazard to the ambulant or semi-ambulant patient who is being encouraged to transfer in and out of bed independently. In 1963 the general purpose hospital bedstead was the subject of a design study (King’s Fund Working Party, 1967) which resulted in the King’s Fund specification for adjustable height beds. In their highest positions these adjustable height beds provide a convenient working bench for hospital staff and also minimize lifting of patients from bed to trolley (see Pheasant, 1987). In their lowest positions these beds are at an acceptable seat height for patients and this eases self-transfer from bed to chair. From a recent study by the author, it can be estimated that adjustable height beds account for about two-thirds of all hospital bedsteads (Bell et al., 1984). If chairs with wheels are provided in wards then patients can be transported within the ward area and between hospital departments. Adjustable height trolleys, plinths, X-ray tables and operating theatre tables are now readily available. There are also a variety of fried height chairs with different seat heights but adjustable height chairs are less commonly found in hospitals. One apparent method of minimizing patient-lifting during changes from lying to sitting position is to produce equipment which offers both support modes and can be converted from trolley to chair by a power assisted mechanism (see Bell, 1984). Toilets and baths
Encouraging a patient to use a bedside commode or a fixed W.C. in a hospital ward toilet presents similar lifting problems to those of transferring a patient in and out of a chair. The semi-ambulant patient with the use of walking aids, grab rails and raised toilet seats can use a toilet independently. Wheelchairs or special commode chairs-on-wheels, i.e. the sani-chair, can be used with the chairbound. The added complication to the nursing staff is in assisting patients with their hygiene and in adjusting their clothing in the often confined spaces of hospital toilets. Bathing patients outwith the bed, however, presents even more problems. Whereas bed related lifting aids attracted the attention of inventors up to the 1950’s, bath related lifting aids have attracted particular attention from the 1960’s. Simple bath aids such as grab rails and bath seats are amongst the most commonplace aids to be found in both hospitals and the homes of disabled people. A variety of adjustable height bath seats have been invented (see Norton, 1970; and Bell, 1984). Andrews (1971) described six different bath or shower systems for the handicapped which must have been developed in or before the 1960s. In some designs the seated patient was wheeled in a special chair support into a special bath or shower which incorporated an access door which could be closed and made water-tight. In other designs the recumbent or semi-recumbent patient was lowered on a special trolley into a appropriate bathing or showering receptacle. Hoists which were developed around the 1950’s were also used for bathing and one very specific development has been the fixed bath hoist. ’
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One of the most recent developments in special bath equipment is the adjustable height bath. When set at a relatively low height ambulant patients can enter and leave the bath independently. At a high height nursing staff can attend to a patient more easily without the stressful bending required with conventional baths. Hoists can also be used to transfer patients in and out of the bath. Mobile hoists on wheels The patient-lifter described by Gubbins (1947) was commercially available until 1977 as the Cullen Hospital Crane and one model was available with castors to facilitate patient transport. A number of other devices for lifting and transporting a recumbent patient have been produced including the Jordan Lift and the Techlem Lift (see Tarling, 1980). However, it appears that the first commercially available mobile hoist used for lifting and transporting patients in a sitting position was the Hoyer hoist. This is similar in design principle to he industrial mobile hoist and the design was presumably based on the industrial model. Published literature on the Hoyer and similar mobile hoists is only available from the 1950’s (Rishworth, 1956; Cicenia et al., 1957; Narrow, 1960; Grant, 1961). By the late 1950’s mobile hoists of similar design to the Hoyer hoist included the Easicarri, F. J. Payne’s Oxford, the Zimmer hoist, the L.P.C., the Little Plumstead, the Gaillard, the Headington Sherpa, the Florence Nightingale and the lpswich hoist. With the exception of F. J. Payne’s New Oxford and the Zimmer Heavy Duty hoist, none of these hoists are still produced. The Steel Nurse (Anon, 1975) was developed in Holland in 1964 and imported to the United Kingdom. The Oxford hoist was redesigned as the New Oxford in 1966 and the new design incorporated an adjustable width base. Mecanaids introduced their B model Ambulift in 1965 (Gifford, 1966). Perhaps the most important feature of the Ambulift was its rigid seat, included because nursing staff apparently disliked existing sling systems. Rigid seat supports were in use in other bathing systems in the 1960’s, for example, in the Droitwich Bath hoist (see Norton, 1970; Andrews, 1971). Interestingly, Mecanaids then introduced a sling-type C model Ambulift in 1970 and a convertible (rigid seat or sling) D model Ambulift in 1972. Arjo AB of Sweden introduced a unique rigid seat Arjo Pilot hoist to the United Kingdom in 1972 and their Lift Bath Chair in 1980 (see Bell, 1984). In the late 1960’s it had become apparent to manufacturers that the demand for mobile hoists on wheels was falling into two main categories: small hoists for the domestic use of disabled people and their attendants which could be put into the boot of a British car and larger hoists with a wider application for hospital and residential homes. By 1976 this series of smaller domestic hoists included the Hoyer Travel-Lifter, Mecanaids’ Mecalift, Carters’ Mini-Lift (or Medi-Hoist) and F. J. Payne’s Isis hoist. Mobile overhead hoists on tracks Nyquist and Clifton (1954) described an externally powered mobile hoist designed by a patient in the United States in 1950. The device was self-operated by the patient, utilized and overhead track for transport and two electric motors for hoisting and transport across the overhead track. Grant (1961) also described overhead hoists on tracks in use in the 1950’s in the United Kingdom, some manually operated and some electrically operated. However, it is not clear when these types of hoist first become commercially available, although one manufacturer, Wessex Medical Equipment Co., was established in 1966.
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Currently, this type of hoist is used only in domiciliary situations and can be provided by Local Authority Social Work Departments to disabled people. They are apparently being increasingly used in the smaller hospital wards in Sweden but are not used to any extent in hospitals in the United Kingdom.
Patient-lifting needs, practice and problems
From studies in hospital wards in the United Kingdom (see Bell, 1984) it can be estimated that patient-lifting problems exist in some 75% of U.K. hospital wards, and in terms of patient numbers, some 25% of the U.K. hospital patient population require specified lifting on any given day. Geriatric patients account for about 50% of the overall lifting problem, with general medicine, surgery and orthopaedic patients accounting for a further 25% of the problem. The remaining 25% of patients requiring lifting are spread throughout some 30 other clinical specialities. The most common patient-lifting tasks undertaken in wards are: (i) lifting patients in and out of chairs; (ii) repositioning patients within either a chair or bed; (iii) lifting patients on and off toilets; (iv) lifting patients in and out of bed; and (v) lifting patients in and out of baths. For each of these tasks manual lifting is most often used, each task is considered by nursing staff to be of comparable importance, generally two members of staff are involved in the lifting or assistance and the physical effort involved is considered by staff to be high (Bell et al., 1979a; Bell, 1984). Mobile hoists are available in about 75% of long-stay wards and about 40% of acute wards. In nine out of 10 cases the hoist available is a Mecanaids Ambulift and the majority of these Ambulifts, i.e. some two-thirds, are D model Ambulifts which can be used with a rigid seat or slings. These hoists are, however, almost invariably used only with the rigid seat attachment for lifting patients over the rim of the bath and are seldom used for lifting patients at the bedside or for transporting patients to and from bed or bath (Bell et al., 1979b; Bell, 1984). The majority of hospital beds are adjustable height models (Bell et al., 1984). Adjustable height baths are not, as yet, in common use. In addition, many NHS hospitals were built more than 75 yr ago and manoeuvring space in wards, toilets and bathrooms is very variable from hospital to hospital and indeed ward to ward (Bell, 1984). The problems of lifting or assisting patients in hospitals are fairly extensive and the concurrent hazard of back injury to staff is a matter of serious concern (HSAC, 1984). However, it should be appreciated that there is no single lifting problem and no single, simple solution. Concentration on a specific part of patient-lifting without an appreciation of the often conflicting needs of individual patients, attendants, ward environments and lifting tasks may result in a device which is simply not utilized to any effective extent. Innovations in the design of equipment and tools for patient-lifting should not be discouraged. Nevertheless, this review of past and existing devices should make designers aware of the limited use made of patient-lifting equipment on a routine basis. Further, the evaluation of each existing lifting device to ensure minimum standards of safety, patient comfort and ease of operation is necessary. However, again it should be appreciated that changes in ergonomic amd engineering design based on particular situations will not necessarily result in increased utilization for the population most at risk. Where improvements, such as the better manoeuvrability of mobile equipment can be achieved at little cost then this must be pursued. For example, better equipment assembly to ensure
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an accurate vertical alignment of castors would improve the manoeuvrability of current mobile hoists (Bell, 1984). More awareness of the problems caused by incompatibility of ward equipment could and should improve work routines for hospital staff and their patients.
Conclusion
The reasons why patient-lifting equipment is not used routinely to any significant extent are quite complex. The stereotyped statements are that hoists take too much time or are too much trouble or that patients dislike them. However, these are not general or incontrovertible truths. According to nursing staff the Macanaids’ Ambulift is used for part of the bathing task fairly routinely because this is a potentially hazardous task for patients who are wet and slippery; nevertheless, three out of four wards with patient-lifting needs still use manual lifting more often than a hoist for bathing patients (Bell, 1984). There are real practical reasons why hoists are not willingly used routinely. For example, a range of alternative devices and accessories are not readily available to each ward; levels of knowledge on hoists are low; ward, toilet and bathroom space is often restricted; ward equipment is not always compatible; and, despite a widespread awareness of the problem of back injury, motivation is low. It should be apparent from the range of technical developments briefly outlined here that the problem of the physical management, lifting and transporting of patients has certainly received attention. Indeed one could design an idealized patient management facility with existing commercially available equipment for an individual patient if resources were not limited. However, dealing with the extensive routine problems for changing populations of patients and attendants within reasonable, acceptable costs in existing NHS hospitals is a problem of a different nature. In addition to efforts to produce new technical solutions to patient-lifting, transfer and transportation, factors such as education, purchasing policies and those administrative policies which involved nursing equipment may be very relevant to the final use made of equipment. With respect to the equipment, attention must be paid to the four variables, the patient, the attendant, the task and the environment, to achieve a systems approach to patient handling.
Acknowledgements-The original study on which this paper is based was funded by DHSS and undertaken in the Rehabilitation Studies Unit, Department of Orthopaedic Surgery, University of Edinburgh.
References Andrews, J. (1971). Helping the handicapped patient to have a comfortasble bath. W/d Med. 6, 88-89. Anon (1975). Steel nurse-discussion about a mechanical patient lifter. Osterr Krunkepflgex, 28, 12-14. Bell, F. (1979). Patient hoist biomechanics. Br. J. occup. Ther. 42, 10-17. Bell, F. (1984). Patient-Lifting Devices in Hospitals. Croom Helm, Beckenham, Kent. Bell, F., Dalgity, M. E. M. Fennel, M.-J. and Aitken, R. C. B. (1979a). Hospital ward patient lifting tasks. Ergonomics 22, 1257-1273. Bell, F., Dalgity, M. E., Osborne, S. J. P. and Aitken, R. C. B. (1979b). The use of patient hoists in hospital wards. ht. J. Rehabil. Res. 2, 312-313. Bell, F. and Fennell, M.-J. (1980). Equipment for disability evaluation. DHSS, Demonstration Centres in Rehub. Newslett. 19, 6-8. Bell, F., Hill, I. M., Lambert, L. C. and McManus, A. (1984). Investigation of patient support systems. Final report to the Department of Health and Social Security, London, University of Edinburgh, Edinburgh.
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BSI (1979). Manually Operated mobile patient lifting devices. BS 5827 (British Standards Institution, London). Cicenia, E. F., Hoberman, M. and Dervitz, H. L. (1957). Use of the invalid lifter in the care of the severely disabled patient. Arch. Phys. Med. Rehub. 30, 101-108. Ebbinghaus, K. D. (1952). Eine neue krankenhebevorrichtung. ArzlicheWochenschrtft 7, 158-159. Gifford, M. E. (1966). Lifting patients, a mobile apparatus. Nurs. Times 62(29), 22 July, 977. Grant, W. R. (1961). Principles of rehabilitation. 111 Hoists and slings. Practitioner 186, 391-395. Gubbins, J. (1947). Apparatus for lifting patients. Br. Med. J. II 25 October, 666. Health Services Advisory Committee (1984) Lifting Patients in the Health Service. HMSO, London. Hoyland, F. (1973). Evaluation Unit Report. Department of Orthopaedic Surgery, University of Edinburgh. Hunt, J. H. (1954). The Huddleston nursing hoist. Br. Med. J. II 13 November, 1161-1162. Jeanmarie (1940). Flaschenzug als krankenheber. Therupie Gegenw. 81, 462-463. King’s Fund Working Party (1967). Design of Hospital Bedsteads. King Edward’s Hospital Fund for London. Kostrubala, J. G. and Wagner, A. G. (1948). Electric lift, an aid in the treatment of decubitus ulcers. Surgery 23, 298-300. Kube (1976). Rapport I-Patientlyftar Inom Sjukvard, Nordforsk, Stockholm, Sweden. Lagergren, C. G. (1945). Lyftanordning for Svarskotta Patienter. Nord. Med. (Hygiea) 23, 557-558. Maddox, R. D. (1939). An invalid-lifting apparatus. J. Bone Join? Surg. 21, 470-471. Narrow, B. W. (1960). An hydraulic patient lifter. Am. J. Nurs. 60, 1273-1275. Norton, D. (1970). By accident or design: a study of equipment development in relation to basic nursing problems. W. & S. Livingstone, Edinburgh. Nyquist, R. H. and Clifton, E. (1954). A hoist. Archs phys. Med. Rehabil. 35, 30-34. Palmkvist, K. and Feeney. R. J. (1973) Certain Tynes Hoists f2nd edn). Swedish Institute for the _. ofPersonal ” Handicapped, Bromma. Pheasant, S. (1987). Some anthropometric aspects of workstation design. Int. J. Nurs. Stud. 24, 291-298. Rishworth, H. R. (1956). Invalid hoists and similar nursing aids. La&et 1, 9 June, 903-905. Tarling, C. (1980) Hoists and Their Use. William Heinemann Medical Books Limited, London. Wilshere, E. R., Hollings, E. M. and Nicholas, P. J. R. (1972) Equipmentfor the Disabled. National Fund for Research into Crippling Diseases, London.
Frank Bell teaches in the Department of Physiotherapy at Queen Margaret College, Edinburgh. He was formerly a lecturer in Bioengineering at the University of Strathclyde, Glasgow (1967-1976) and more recently, Senior Research Fellow in the Rehabilitation Studies Unit at the University of Edinburgh (1976-1984). He has published research papers on the topics of pressure sores, patient lifting equipment, aids for the disabled and nursing equipment. He is the author of the book Patient-lifting Devices in Hospitals published in 1984 by Croom Helm (reviewed in this journal 1985, 22, 286-287).
331-337,
0020-7489/87 $3.00+0.00 Pergamon Journals Ltd.
1987
Ergonomic aspects of equipment F. BELL, B.Sc., Ph.D., C.Eng., M.1.Mech.E. Department of Physiotherapy, Queen Margaret College, Clerwood Terrace, Edinburgh EH12 8TS, U.K.
Abstract-Mechanical patient-lifting devices have been available for hospital use for at least the past 100 yr. Mobile hoists have been available since the 1950s and the most common U.K. hospital mobile hoist, the Mecanaids’ Ambulift, has been available since 1966. Recent investigations have confirmed that these devices are not being used to any significant extent to ease most of the patientlifting problems in hospital wards. Attention to four variables, the patient, the attendant, the task and the environment, is essential in determining the right systematic approach to equipment design and selection.
Introduction
Between the mid-1950’s and the mid-1960’s a variety of commercially available hoists were introduced in the United Kingdom to assist in the lifting and movement of physically disabled people. By the late 1960’s it was generally recognized that many of these devices, purchased by hospitals, were simply not being used and were ‘gathering cobwebs’ in cupboards (Norton, 1970). The need for research, evaluation and information on hoists became a focal point for those concerned with aids in the early 1970’s with particular studies being initiated in London (Tarling, 1980), Oxford (Wilshere et al., 1972), Edinburgh (Hoyland, 1973) and Sweden (Palmkvist and Feeney, 1973; Kube, 1976). The Department of Health and Social Security (DHSS) initiated the establishment of standards for the mechanical safety of mobile patient lifters with the British Standards Institution (BSI, 1979). Between 1977 and 1981 the author undertook a specific investigation of the utilization of mobile hoists in hospital in the United Kingdom, funded by the DHSS (Bell et al., 1979a,b; Bell 1979, 1984; Bell and Fennell, 1980). This study revealed that hoists were still not being used to any significant extent to ease most of the patient-lifting problems in hospital wards with perhaps the exception of the bathing task. A brief review of developments in this field during the past century and an outline of the complexity of the problems facing nursing staff may help guide would-be design innovators to gain a perspective of the apparent problems, a necessary first step in tackling possible solutions. For illustrations of the materials described below the reader is referred to Bell (1984). 14 Controller
HMSO
1987. 331
332
F. BELL
Patient-lifters
reviewed
Aids for patients and nurses Aids can be designed to be used either by the patient or by the attendant, i.e. the nurse. For any particular task, whether associated with treatment or personal care, the amount of physical assistance that the patient requires will depend upon his physical and mental capability and his liability; it may be dangerous to allow the patient to exert physical effort even if he is physically able to do so. Simple aids that are available for patients to use today include overhead trapezes, rope ladders, hand blocks, sliding boards, grab rails, bath seats and raised toilet seats. Aids for nursing include adaptations for draw sheets, lifting cushions and levers (e.g. the LIC lifting cushions and Nesbit-Evans Mini-Paroll). Identifying the task and the intended user of an aid are obviously primary criteria in designing an aid. Lifting tasks and clinical management The proportion of elderly patients in the hospital population has been increasing over the past century and this in itself has changed the nature of patient-lifting problems. However, equally important are changes which have occurred in the general clinical management of patients. In the mid-1950’s more emphasis was placed on mobilizing patients at an earlier stage in their care to prevent complications to which the bedfast are prone, such as deep-vein thrombosis and pressure sores. Assisting the movement of the bedfast patient is still a problem today but the earlier ambulation of patients now extends attention to other tasks outwith the bed; patient transfer in and out of bed, in and out of chairs, on and off toilets and, of particular interest to designers for the past 30 yr or so, in and out of baths. Prior to the mid-1950’s, however, the problem of dealing with the bedfast patient apparently attracted most endeavour from inventors and led to a number of almost identical patient-lifting devices. A 19th century catalogue of J. & A. Carters Ltd seen by the author illustrated an ‘invalid lift’ which can be dated to 1880 by the ‘testimonials’ included in the advertisement. A review of the literature reveals at least six similar devices (Maddox, 1939; Jeanmaire, 1940; Lagergren, 1945; Gubbins, 1947; Ebbinghaus, 1952; and Hunt, 1954) each apparently independently invented between 1939 and 1954. All of these devices used a manually operated mechanism to raise the patient’s body, partly or totally, from the mattress. An externally powered patient-lifting device was described by Kostrubala and Wagner in an article in 1948. This was a fixed-point, electrically operated hoist, used to facilitate the changing of patients’ wound dressings. All of these devices were still essentially concerned only with raising or repositioning the patient. For the patient to leave the confines of the bed, the design criteria had to be extended or changed and new problems appeared. Transfer to and from the bed Transferring or transporting the recumbent patient between his bed and, say, the operating theatre or another hospital department, is a common task today and must have been a common task in the past also. Manual lifting combined with the use of stretchers and trolleys would have been the simplest method and this is best achieved with the patient on a relatively high bed platform. In addition, nursing and medical procedures for the bedfast patient are more easily undertaken if the bed mattress is at a working bench height. The device described by Gubbins (1947) was commercially available as the Cullen Hospital Crane up
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until 1977 and one model incorporated castors to allow transportation of the recumbent patient. Today some of the most sophisticated patient-handling systems are available for transferring the recumbent patient to and from operating theatres. However, mobilizing the ambulent, semi-ambulant or chair-fast patient within the hospital ward presents quite different problems associated with conflicting needs. Beds and chairs
A high hospital bed which can be an advantage to nursing and medical staff when dealing with a patient, can present a potential hazard to the ambulant or semi-ambulant patient who is being encouraged to transfer in and out of bed independently. In 1963 the general purpose hospital bedstead was the subject of a design study (King’s Fund Working Party, 1967) which resulted in the King’s Fund specification for adjustable height beds. In their highest positions these adjustable height beds provide a convenient working bench for hospital staff and also minimize lifting of patients from bed to trolley (see Pheasant, 1987). In their lowest positions these beds are at an acceptable seat height for patients and this eases self-transfer from bed to chair. From a recent study by the author, it can be estimated that adjustable height beds account for about two-thirds of all hospital bedsteads (Bell et al., 1984). If chairs with wheels are provided in wards then patients can be transported within the ward area and between hospital departments. Adjustable height trolleys, plinths, X-ray tables and operating theatre tables are now readily available. There are also a variety of fried height chairs with different seat heights but adjustable height chairs are less commonly found in hospitals. One apparent method of minimizing patient-lifting during changes from lying to sitting position is to produce equipment which offers both support modes and can be converted from trolley to chair by a power assisted mechanism (see Bell, 1984). Toilets and baths
Encouraging a patient to use a bedside commode or a fixed W.C. in a hospital ward toilet presents similar lifting problems to those of transferring a patient in and out of a chair. The semi-ambulant patient with the use of walking aids, grab rails and raised toilet seats can use a toilet independently. Wheelchairs or special commode chairs-on-wheels, i.e. the sani-chair, can be used with the chairbound. The added complication to the nursing staff is in assisting patients with their hygiene and in adjusting their clothing in the often confined spaces of hospital toilets. Bathing patients outwith the bed, however, presents even more problems. Whereas bed related lifting aids attracted the attention of inventors up to the 1950’s, bath related lifting aids have attracted particular attention from the 1960’s. Simple bath aids such as grab rails and bath seats are amongst the most commonplace aids to be found in both hospitals and the homes of disabled people. A variety of adjustable height bath seats have been invented (see Norton, 1970; and Bell, 1984). Andrews (1971) described six different bath or shower systems for the handicapped which must have been developed in or before the 1960s. In some designs the seated patient was wheeled in a special chair support into a special bath or shower which incorporated an access door which could be closed and made water-tight. In other designs the recumbent or semi-recumbent patient was lowered on a special trolley into a appropriate bathing or showering receptacle. Hoists which were developed around the 1950’s were also used for bathing and one very specific development has been the fixed bath hoist. ’
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One of the most recent developments in special bath equipment is the adjustable height bath. When set at a relatively low height ambulant patients can enter and leave the bath independently. At a high height nursing staff can attend to a patient more easily without the stressful bending required with conventional baths. Hoists can also be used to transfer patients in and out of the bath. Mobile hoists on wheels The patient-lifter described by Gubbins (1947) was commercially available until 1977 as the Cullen Hospital Crane and one model was available with castors to facilitate patient transport. A number of other devices for lifting and transporting a recumbent patient have been produced including the Jordan Lift and the Techlem Lift (see Tarling, 1980). However, it appears that the first commercially available mobile hoist used for lifting and transporting patients in a sitting position was the Hoyer hoist. This is similar in design principle to he industrial mobile hoist and the design was presumably based on the industrial model. Published literature on the Hoyer and similar mobile hoists is only available from the 1950’s (Rishworth, 1956; Cicenia et al., 1957; Narrow, 1960; Grant, 1961). By the late 1950’s mobile hoists of similar design to the Hoyer hoist included the Easicarri, F. J. Payne’s Oxford, the Zimmer hoist, the L.P.C., the Little Plumstead, the Gaillard, the Headington Sherpa, the Florence Nightingale and the lpswich hoist. With the exception of F. J. Payne’s New Oxford and the Zimmer Heavy Duty hoist, none of these hoists are still produced. The Steel Nurse (Anon, 1975) was developed in Holland in 1964 and imported to the United Kingdom. The Oxford hoist was redesigned as the New Oxford in 1966 and the new design incorporated an adjustable width base. Mecanaids introduced their B model Ambulift in 1965 (Gifford, 1966). Perhaps the most important feature of the Ambulift was its rigid seat, included because nursing staff apparently disliked existing sling systems. Rigid seat supports were in use in other bathing systems in the 1960’s, for example, in the Droitwich Bath hoist (see Norton, 1970; Andrews, 1971). Interestingly, Mecanaids then introduced a sling-type C model Ambulift in 1970 and a convertible (rigid seat or sling) D model Ambulift in 1972. Arjo AB of Sweden introduced a unique rigid seat Arjo Pilot hoist to the United Kingdom in 1972 and their Lift Bath Chair in 1980 (see Bell, 1984). In the late 1960’s it had become apparent to manufacturers that the demand for mobile hoists on wheels was falling into two main categories: small hoists for the domestic use of disabled people and their attendants which could be put into the boot of a British car and larger hoists with a wider application for hospital and residential homes. By 1976 this series of smaller domestic hoists included the Hoyer Travel-Lifter, Mecanaids’ Mecalift, Carters’ Mini-Lift (or Medi-Hoist) and F. J. Payne’s Isis hoist. Mobile overhead hoists on tracks Nyquist and Clifton (1954) described an externally powered mobile hoist designed by a patient in the United States in 1950. The device was self-operated by the patient, utilized and overhead track for transport and two electric motors for hoisting and transport across the overhead track. Grant (1961) also described overhead hoists on tracks in use in the 1950’s in the United Kingdom, some manually operated and some electrically operated. However, it is not clear when these types of hoist first become commercially available, although one manufacturer, Wessex Medical Equipment Co., was established in 1966.
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Currently, this type of hoist is used only in domiciliary situations and can be provided by Local Authority Social Work Departments to disabled people. They are apparently being increasingly used in the smaller hospital wards in Sweden but are not used to any extent in hospitals in the United Kingdom.
Patient-lifting needs, practice and problems
From studies in hospital wards in the United Kingdom (see Bell, 1984) it can be estimated that patient-lifting problems exist in some 75% of U.K. hospital wards, and in terms of patient numbers, some 25% of the U.K. hospital patient population require specified lifting on any given day. Geriatric patients account for about 50% of the overall lifting problem, with general medicine, surgery and orthopaedic patients accounting for a further 25% of the problem. The remaining 25% of patients requiring lifting are spread throughout some 30 other clinical specialities. The most common patient-lifting tasks undertaken in wards are: (i) lifting patients in and out of chairs; (ii) repositioning patients within either a chair or bed; (iii) lifting patients on and off toilets; (iv) lifting patients in and out of bed; and (v) lifting patients in and out of baths. For each of these tasks manual lifting is most often used, each task is considered by nursing staff to be of comparable importance, generally two members of staff are involved in the lifting or assistance and the physical effort involved is considered by staff to be high (Bell et al., 1979a; Bell, 1984). Mobile hoists are available in about 75% of long-stay wards and about 40% of acute wards. In nine out of 10 cases the hoist available is a Mecanaids Ambulift and the majority of these Ambulifts, i.e. some two-thirds, are D model Ambulifts which can be used with a rigid seat or slings. These hoists are, however, almost invariably used only with the rigid seat attachment for lifting patients over the rim of the bath and are seldom used for lifting patients at the bedside or for transporting patients to and from bed or bath (Bell et al., 1979b; Bell, 1984). The majority of hospital beds are adjustable height models (Bell et al., 1984). Adjustable height baths are not, as yet, in common use. In addition, many NHS hospitals were built more than 75 yr ago and manoeuvring space in wards, toilets and bathrooms is very variable from hospital to hospital and indeed ward to ward (Bell, 1984). The problems of lifting or assisting patients in hospitals are fairly extensive and the concurrent hazard of back injury to staff is a matter of serious concern (HSAC, 1984). However, it should be appreciated that there is no single lifting problem and no single, simple solution. Concentration on a specific part of patient-lifting without an appreciation of the often conflicting needs of individual patients, attendants, ward environments and lifting tasks may result in a device which is simply not utilized to any effective extent. Innovations in the design of equipment and tools for patient-lifting should not be discouraged. Nevertheless, this review of past and existing devices should make designers aware of the limited use made of patient-lifting equipment on a routine basis. Further, the evaluation of each existing lifting device to ensure minimum standards of safety, patient comfort and ease of operation is necessary. However, again it should be appreciated that changes in ergonomic amd engineering design based on particular situations will not necessarily result in increased utilization for the population most at risk. Where improvements, such as the better manoeuvrability of mobile equipment can be achieved at little cost then this must be pursued. For example, better equipment assembly to ensure
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an accurate vertical alignment of castors would improve the manoeuvrability of current mobile hoists (Bell, 1984). More awareness of the problems caused by incompatibility of ward equipment could and should improve work routines for hospital staff and their patients.
Conclusion
The reasons why patient-lifting equipment is not used routinely to any significant extent are quite complex. The stereotyped statements are that hoists take too much time or are too much trouble or that patients dislike them. However, these are not general or incontrovertible truths. According to nursing staff the Macanaids’ Ambulift is used for part of the bathing task fairly routinely because this is a potentially hazardous task for patients who are wet and slippery; nevertheless, three out of four wards with patient-lifting needs still use manual lifting more often than a hoist for bathing patients (Bell, 1984). There are real practical reasons why hoists are not willingly used routinely. For example, a range of alternative devices and accessories are not readily available to each ward; levels of knowledge on hoists are low; ward, toilet and bathroom space is often restricted; ward equipment is not always compatible; and, despite a widespread awareness of the problem of back injury, motivation is low. It should be apparent from the range of technical developments briefly outlined here that the problem of the physical management, lifting and transporting of patients has certainly received attention. Indeed one could design an idealized patient management facility with existing commercially available equipment for an individual patient if resources were not limited. However, dealing with the extensive routine problems for changing populations of patients and attendants within reasonable, acceptable costs in existing NHS hospitals is a problem of a different nature. In addition to efforts to produce new technical solutions to patient-lifting, transfer and transportation, factors such as education, purchasing policies and those administrative policies which involved nursing equipment may be very relevant to the final use made of equipment. With respect to the equipment, attention must be paid to the four variables, the patient, the attendant, the task and the environment, to achieve a systems approach to patient handling.
Acknowledgements-The original study on which this paper is based was funded by DHSS and undertaken in the Rehabilitation Studies Unit, Department of Orthopaedic Surgery, University of Edinburgh.
References Andrews, J. (1971). Helping the handicapped patient to have a comfortasble bath. W/d Med. 6, 88-89. Anon (1975). Steel nurse-discussion about a mechanical patient lifter. Osterr Krunkepflgex, 28, 12-14. Bell, F. (1979). Patient hoist biomechanics. Br. J. occup. Ther. 42, 10-17. Bell, F. (1984). Patient-Lifting Devices in Hospitals. Croom Helm, Beckenham, Kent. Bell, F., Dalgity, M. E. M. Fennel, M.-J. and Aitken, R. C. B. (1979a). Hospital ward patient lifting tasks. Ergonomics 22, 1257-1273. Bell, F., Dalgity, M. E., Osborne, S. J. P. and Aitken, R. C. B. (1979b). The use of patient hoists in hospital wards. ht. J. Rehabil. Res. 2, 312-313. Bell, F. and Fennell, M.-J. (1980). Equipment for disability evaluation. DHSS, Demonstration Centres in Rehub. Newslett. 19, 6-8. Bell, F., Hill, I. M., Lambert, L. C. and McManus, A. (1984). Investigation of patient support systems. Final report to the Department of Health and Social Security, London, University of Edinburgh, Edinburgh.
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BSI (1979). Manually Operated mobile patient lifting devices. BS 5827 (British Standards Institution, London). Cicenia, E. F., Hoberman, M. and Dervitz, H. L. (1957). Use of the invalid lifter in the care of the severely disabled patient. Arch. Phys. Med. Rehub. 30, 101-108. Ebbinghaus, K. D. (1952). Eine neue krankenhebevorrichtung. ArzlicheWochenschrtft 7, 158-159. Gifford, M. E. (1966). Lifting patients, a mobile apparatus. Nurs. Times 62(29), 22 July, 977. Grant, W. R. (1961). Principles of rehabilitation. 111 Hoists and slings. Practitioner 186, 391-395. Gubbins, J. (1947). Apparatus for lifting patients. Br. Med. J. II 25 October, 666. Health Services Advisory Committee (1984) Lifting Patients in the Health Service. HMSO, London. Hoyland, F. (1973). Evaluation Unit Report. Department of Orthopaedic Surgery, University of Edinburgh. Hunt, J. H. (1954). The Huddleston nursing hoist. Br. Med. J. II 13 November, 1161-1162. Jeanmarie (1940). Flaschenzug als krankenheber. Therupie Gegenw. 81, 462-463. King’s Fund Working Party (1967). Design of Hospital Bedsteads. King Edward’s Hospital Fund for London. Kostrubala, J. G. and Wagner, A. G. (1948). Electric lift, an aid in the treatment of decubitus ulcers. Surgery 23, 298-300. Kube (1976). Rapport I-Patientlyftar Inom Sjukvard, Nordforsk, Stockholm, Sweden. Lagergren, C. G. (1945). Lyftanordning for Svarskotta Patienter. Nord. Med. (Hygiea) 23, 557-558. Maddox, R. D. (1939). An invalid-lifting apparatus. J. Bone Join? Surg. 21, 470-471. Narrow, B. W. (1960). An hydraulic patient lifter. Am. J. Nurs. 60, 1273-1275. Norton, D. (1970). By accident or design: a study of equipment development in relation to basic nursing problems. W. & S. Livingstone, Edinburgh. Nyquist, R. H. and Clifton, E. (1954). A hoist. Archs phys. Med. Rehabil. 35, 30-34. Palmkvist, K. and Feeney. R. J. (1973) Certain Tynes Hoists f2nd edn). Swedish Institute for the _. ofPersonal ” Handicapped, Bromma. Pheasant, S. (1987). Some anthropometric aspects of workstation design. Int. J. Nurs. Stud. 24, 291-298. Rishworth, H. R. (1956). Invalid hoists and similar nursing aids. La&et 1, 9 June, 903-905. Tarling, C. (1980) Hoists and Their Use. William Heinemann Medical Books Limited, London. Wilshere, E. R., Hollings, E. M. and Nicholas, P. J. R. (1972) Equipmentfor the Disabled. National Fund for Research into Crippling Diseases, London.
Frank Bell teaches in the Department of Physiotherapy at Queen Margaret College, Edinburgh. He was formerly a lecturer in Bioengineering at the University of Strathclyde, Glasgow (1967-1976) and more recently, Senior Research Fellow in the Rehabilitation Studies Unit at the University of Edinburgh (1976-1984). He has published research papers on the topics of pressure sores, patient lifting equipment, aids for the disabled and nursing equipment. He is the author of the book Patient-lifting Devices in Hospitals published in 1984 by Croom Helm (reviewed in this journal 1985, 22, 286-287).