Mechanical Hoists Research Articles

Mobilization in Indian intensive care units: Where do we stand?

Sir, We read with the great interest the article by Rajesh Chawla et al. (2014) surveying the mobilization, analgesic, and sedative practises in Indian intensive care units (ICUs).[1] We appreciate the authors for the greater efforts in evaluating the intensive care practises at a larger scale. Though the response rate was poor(11%), the study paves way for utilization of several standardization procedures including therapeutic practises in ICUs. Especially the study has demonstrated mobilization practices in Indian ICUs. Mobilization is a standard practice in western ICUs. Earlier research had elaborated effects of early mobilization in maintenance of muscle mass, thus preventing critical illness myoneuropathy, increasing functional capacity, early functional independence, early weaning, reduction of ventilator-associated pneumonia and critical illness, reduction of intensive care, and hospital stay, improving neuropsychiatric outcomes such as ICU delirium, reduction of caregiver stress, and health resource utilization.[2,3,4,5,6,7] Western literature including meta-analysis and systematic reviews are available stating significant evidence in mobilization of critically ill patients.[2,5,7] In the article by Rajesh Chawla (2014), we are not surprised by the fact that out of 94% (614 physician responders), only 13% (90 physicians) were in favor of mobilizing critically ill patients with equipments (ventilators and tubes).[1] Western literature supports mobilization of intensive care patients with ventilators and assistive devices.[8,9] Safety in mobilizing intensive care patients with ventilators and tubes are proved earlier.[10,11] We disagree the author in holding only physician apprehension as responsible for poor mobilization practises in Indian ICUs. This may be due to lack of infrastructure, expertise training in handling mobile ventilators, and mobilizing aids, such as mechanical hoists (passive transfer using mechanical aids),[12] lack of therapist's and nurse's knowledge of initiating and progressing early mobilization in ICU, criteria for termination of mobilization, screening for risk stratification during mobilization, knowledge about mobility aids, and safe handling techniques.[10,11] New promising researches are put forward depicting the positive attitude of mobilizing patients in Indian ICUs in past few years.[13,14,15] We recommend future trials in elucidating the effects of early mobilization in intensive care outcomes in Indian medical pitch. Apart from the study mentioned, limitation, such as the poor response rate poor responders, few other setbacks prevent from generalization of the study results in Indian clinical arena.[1] First, majority of the responders are age below 40 (59%) and ICU practising experience below 5 years (41%). Since this survey partially depends on the experience of the practising intensivists, the practise patterns elaborated in the study are questionable to certain extent. Second, the majority of the responders are from institutions with less than 20 ICU beds (77%). Though the bed strength falls within the standardization of Indian Society for Critical care medicine (ISCCM), the systematic mobilization program may not be implemented at ease within the constrained perimeter of the ICUS included in the present study. Further, the current survey could have inclusions of various ICUs such as cardiology, neurology, post-surgical and traumatic practice patterns differing between ICUs within an Insitution itself which may question the applicability of the results in Indian clinical arena. Other than the above limitations, the study adds evidence to the current therapeutic practises, newer association between sedation and mobilization and neuropsychiatric outcomes such as delirium in Indian intensive care settings. We appreciate once again the authors for demonstrating lag of current ICU practices behind the standard guidelines of therapeutic applications in Indian ICUs.

Application of the AE Technology to Fault Diagnosis in Gezhouba Dam Shiplock Mechanical Hoist Reducer

Acoustic emission detection principle was used in testing the working status of Gezhouba Dam ship lock mechanical hoist reducer. According to wavelet analysis technology, high frequency signals of the acoustic emission is decomposed and reconstructed so as to eliminate noise and improve the signal-to-noise ratio. Then the Hilbert envelope transformation analysis is adopted to identify fault information. The results show that wavelet envelope spectrum analysis of the acoustic emission signals can be effectively used in fault diagnosis of reduction gearbox.

Vertical dimensions of suspended horses

The dimensions of anaesthetised hobbled horses during suspension and transfer onto the operating table are unknown. These data are required for the cost-effective construction of equine surgical facilities. To measure the distance from the toe to dependent back margin (Bsusp) and poll (Psusp) of anaesthetised suspended horses and correlate them with readily obtained measures from standing animals. Digital photographs of suspended horses were taken in the anaesthesia induction box at a fixed position that allowed trigonometric determination of Bsusp and Psusp. These values were linked with body mass, height at the withers (Wstand), the length of the crest from the poll to the withers (crest) and of the back (back) from the withers to the crop, by deriving an equine morphological index (EMI) using principal component analysis. The EMI and other linear variables were then subjected to single variable regression analysis. EMI was 0.531mass((kg)) + 0.528Wstand((cm)) + 0.469crest((cm)) + 0.468back((cm)) . Bsusp was most accurately estimated using the expression Bsusp= 118.71 + 0.128EMI while Psusp was most strongly associated with Wstand, i.e. Psusp= 46.9 + 1.01Wstand((cm)) . The height of suspended horses at the most ventral margin of the back and the poll can be estimated from measures taken from the standing animal. The data will allow the more informed planning and construction of equine surgical facilities in which mechanical hoists are used.

Prevention of Disabling Back Injuries in Nurses by the Use of Mechanical Patient Lift Systems

Occupational back pain in nurses (OBPN) constitutes a major source of morbidity in the health care environment. According to the National Institute for Occupational Safety and Health (NIOSH), occupational back injury is the second leading occupational injury in the United States. Among health care personnel, nurses have the highest rate of back pain, with an annual prevalence of 40-50% and a lifetime prevalence of 35-80%. The American Nursing Association believes that manual patient handling is unsafe and is directly responsible for musculoskeletal disorders encountered in nurses. It has been well documented that patient handling can be done safely with the use of assistive equipment and devices that eliminate these hazards to nurses that invite serious back injuries. The benefit of assistive patient handling equipment is characterized by the simultaneous reduction of the risk of musculoskeletal injury to the nursing staff and improvement in the quality of care for patient populations. To understand the cause of disabling injuries in health care workers, several factors must be considered, including the following: (1) anatomy/physiology of the back, (2) risk factors, (3) medical legal implications, and (4) prevention. Among nurses, back, neck, and shoulder injuries are commonly noted as the most prevalent and debilitating. While mostly associated with dependant patient care, the risk for musculoskeletal injury secondary to manual patient handling crosses all specialty areas of nursing. The skeletal defects of an abnormal back make the back more susceptible to occupational injury, even under normal stress conditions. Workers compensation guidelines for occupational back injury differ in public and private health care sectors from state to state. Nursing personnel should be reminded that the development of back pain following occupational activities in the hospital should be reported immediately to the Occupational Health Department. A nurse's failure to report OBPN immediately has resulted in numerous denials of claims for rehabilitation and compensation that nurses deserve. Experts believe that training in proper body mechanics does not prevent back injury. Consequently, focus has been placed on other innovative injury prevention programs, including the use of engineering controls as well as the "lift team" method. Ergonomics involves the use of mechanical devices (e.g., walking belt and mechanical hoist) to aid in patient lifting and transferring tasks. Guldmann Inc. has devised ceiling lift systems and slings during the past 20 years. They have successfully completed thousands of installations worldwide, covering a wide range of challenging conditions and complex environments. The Guldmann ceiling-mounted hoist system consists of a wide range of lifting units, rail components, and a complete assortment of lifting slings and accessories. Its sling is made of polyester, which is characterized by its strength and elasticity. It retains its shape and is dirt repellent and easy to maintain. The Guldmann network has one of the largest and indisputably most experienced group of certified installers in the United States. The "lift team" method was devised to remove nursing personnel from the everyday task of moving patients. This type of intervention assumes that lifting is a specialized skill to be performed only by expert professional patient movers who have been thoroughly trained in the latest lifting device techniques.

Design Guidelines for Spillway Gates

This article discusses the most common types of spillway gates including radial gates, vertical lift gates, and flap gates including inflatable gates, and their application. Design considerations for each type are explained. Design and application considerations for different types of spillway gate operators are also included. Items covered for gates include gate geometry, gate proportions, location of gate hoists, location of gate trunnions, trunnion anchorage arrangements, gate seals and sealing arrangements, use of dogging devices, wave deflectors, flow splitters, corrosion protection including use of cathodic protection, and ice problems associated with spillway gates. Items covered for hoists include selection criteria for hydraulic and mechanical hoists, functional requirements of the hoists, use and type of position indicators, normal speed of opening and closing, use of automatic controls, the need for maximizing the minimum opening, and automatic stopping of the gates at set intervals to prevent unintentional spilling. Permissible leakage rate through the gates is also included.

A qualitative research study into the use of manually operated mobile hoists and the need for tailored ‘job aids’

A small-scale study of the activity of hoisting was conducted using task analysis. Two mobile hoists were used and the task analysed was specified as: ‘To lift a subject from a lying position on a divan bed into a commode chair with the use of a mobile mechanical hoist and appropriate sling.’

Prevention of back injuries in healthcare workers

A laboratory study was conducted to evaluate five different manual techniques (two-person lifting; rocking and pulling the patient using a gait belt with two persons; walking belt with handles with one and two persons; and a patient handling sling with cutouts with one person) for transferring patients from wheelchair to toilet and toilet to wheelchair. In addition, three different mechanical hoists (H, T and A) were studied for transferring patients from toilet to wheelchair. Six female nursing students with prior patient transfer experience served both as nurses and passive patients. The mean trunk flexion moments, erector spinae muscle forces and compressive forces for the four manual pulling methods ranged from 93 to 133 Nm, 1861 to 2653 N and 1974 to 2745 N, respectively, as compared to about 200 Nm, 4100 N and 4800 N for two-person manual lifting. Manual lifting was perceived to be the most stressful by the nurses and the least comfortable and secure by the patients. Hoist A was perceived to be the least stressful and the most comfortable and secure. Hoists H and T were perceived to be more stressful, less comfortable and less secure than the walking belt. An intervention study was conducted in two units of a nursing home (140 beds and 57 NAs) to determine the effectiveness of ergonomic changes. Nursing assistants (NAs) in the two units of the nursing home were trained in the use of selected devices and shower rooms and toilets were modified. The mean acceptability rates for walking belt and hoist A were 81% and 87%, respectively. The reported incidence and severity rates for back injuries over 13 months decreased from 83 to 43 and from 634 to 0, respectively, after the intervention. Nursing assistants perceived their job as “very light” after the intervention as compared to between “somewhat hard” and “hard” before intervention.

Reducing back stress to nursing personnel: an ergonomic intervention in a nursing home.

A prospective epidemiologic study was conducted in two units (140 beds and 57 nursing assistants) of a nursing home to demonstrate the efficacy of an ergonomic intervention strategy to reduce back stress to nursing personnel. The total programme involved the following: determining patient handling tasks perceived to be most stressful by the nursing assistants (NAs); performing an ergonomic evaluation of these tasks; and conducting a laboratory study to select patient transferring devices perceived to produce less physical stress than existing manual patient-handling methods. The intervention phase included training NAs in the use of these devices, modifying toilets and shower rooms, and applying techniques to patient care. Immediately after completing the intervention programme, a post-intervention analysis (which lasted eight months in unit 1 and four months in unit 2) was performed. A biomechanical evaluation of the physical demands required to perform stressful patient-handling tasks showed that the mean compressive force on the L5/S1 disc, the mean hand force required to make a transfer, and the strength requirements (expressed as percentage female population capable) were 1964 N, 122 N, and 83% after intervention as compared to 4751 N, 312 N, and 41% before intervention. Subjectively, the mean rating of perceived exertion was less than 'very light' after intervention as compared to between 'somewhat hard' and 'hard' before intervention. Overall, the mean acceptability rates for the walking belt and the mechanical hoist were 81% and 87% for patient transfers. The incidence rate for back injuries prior to the intervention, 83 per 200,000 work-hours, decreased to 47 per 200,000 work-hours after the intervention. There were no injuries resulting in lost or restricted work days during the last four months of the post-intervention. It is concluded that an appropriate ergonomic intervention programme offers great promise in reducing physical stress and risk of low-back pain to nursing personnel. However, large-scale studies in different nursing homes are needed to confirm the above findings.

A biomechanical and ergonomic evaluation of patient transferring tasks: wheelchair to shower chair and shower chair to wheelchair

A laboratory study was conducted to evaluate five different manual techniques (two-person manual lifting; rocking and pulling the patient using a gait belt with two persons; walking belt with one and two persons) and three different mechanical hoists (Hoyer lift, Trans-Aid and Ambulift) for transferring patients from wheelchair to shower chair and shower chair to wheelchair. Six female nursing students with prior patient transfer experience served both as nurses and as passive patients. Static biomechanical evaluation showed that the mean trunk flexion moments, erector spinae muscle forces and compressive and shear forces at the L5S1 disc for the four pulling methods ranged from 92 to 125 Nm, 1845 to 2507 N, 1973 to 2641 N and 442 to 580 N, respectively, as compared to about 213 Nm, 4260 N, 5050 N and 926 N for two-person manual lifting. Perceived stress ratings for the shoulder, upper back, lower back and whole body were significantly lower for pulling methods than those for lifting the patient (p less than or equal to 0.01). Patients found pulling techniques, except the gait belt, to be more comfortable and secure than the lifting method (p less than or equal to 0.01). However, most of the nurses believed that Medesign and the one-person walking belt would not work on those patients who cannot bear weight and those who are heavy, contracted or combative. A two-person walking belt was the most preferred method. Two out of three hoists (Hoyer lift and Trans-Aid) were perceived by the nurses to be more stressful than one- and two-person walking belts. The patients found these two hoists to be more uncomfortable and less secure than with three of the five manual methods (one- and two-person walking belts and Medesign). Pulling techniques and hoists took significantly longer amounts of time to make the transfer than manually lifting the patient (p less than or equal to 0.01). The two-person walking belt, using a gentle rocking motion to utilize momentum and a pulling technique, and Ambulift are recommended for transferring patients from wheelchair to shower chair and shower chair to wheelchair.

A biomechanical and ergonomic evaluation of patient transferring tasks: bed to wheelchair and wheelchair to bed

A laboratory study was conducted in an effort to reduce back stress for nursing personnel while performing the patient handling tasks of transferring the patient from bed to wheelchair and wheelchair to bed. These patient handling tasks were studied using five manual techniques and three hoist-assisted techniques. The manual techniques involved one-person and two-person transfers. One manual technique involved a two-person lift of the patient under the arms; the others used a rocking and pulling action and included the use of assistive devices (a gait belt using a two-person transfer, a walking belt with handles using a one-person and a two-person transfer, and a patient handling sling with cutout areas to allow for a hand grip (Medesign) for a one-person transfer). The three mechanical hoists were Hoyer, Trans-Aid and Ambulift. Six female nursing students with prior patient transfer experience served both as nurses and as passive patients. Static biomechanical evaluation showed that pulling techniques, as compared to lifting the patient, required significantly lower hand forces and produced significantly lower erector spinae and compressive forces at the L5/S1 disc (P greater than or equal to 0.01). Shear force, trunk moments and the percentage of females who were capable of performing the transfers (based on static strength simulation) also favoured pulling methods. Perceived stress ratings for the shoulder, upper back, lower back and whole body were lower for pulling methods than those for lifting the patient (P less than or equal to 0.01). Patients found the pulling techniques, with the exception of when using the gait belt, felt more comfortable and more secure than the lifting method (P less than or equal to 0.01). However, a number of subjects believed that the patient handling sling (Medesign) and the walking belt with one person making the transfer would not work for those patients who could not bear weight and those who were heavy, contracted or combative. A walking belt with two persons was the preferred manual method. Two out of three hoists (Hoyer lift and Trans-Aid) were perceived by the nurses to be as physically stressful as manual methods. Patients found these two hoists to be more uncomfortable and felt less secure than with three of the five manual methods (one- and two-person walking belts and Medesign). Ambulift was found to be the least stressful, the most comfortable, and the most secure among all eight methods. Pulling techniques and hoists took significantly longer amounts of time to make the transfer than manually lifting the patient (P less than or equal to 0.01). The two-person walking belt using a pulling technique and Ambulift are recommended for transferring patients from bed to wheelchair and wheelchair to bed. A large-scale field study is needed to verify these recommendations.

Reducing Risk for Back Pain in Nursing Personnel

Transferring the clients from toilet to wheelchair was the task ranked as most stressful by nursing assistants in a nursing home. The compressive force to the L5S1 disc by client weight during the toilet to wheelchair transfer exceeded the action limit permitted as safe by NIOSH. Two of the three mechanical hoists were perceived to be as stressful or more stressful than the moment transfer methods with the walking belt. Of the five manual methods for transferring, the use of the walking belt was determined to be least stressful and most comfortable for nursing subjects and clients.

The handling of patients on geriatric wards: A challenge for on-the-job training

Patient lifting habits were studied on seven geriatric wards in five hospitals. The methods used were workplace analysis, questionnaire and video analysis of lifts. Mechanical hoists were regularly used only on the ward that had well organised on-the-job-training. The reasons given for not using the hoist (lack of space or time, etc) were similar on this and the other wards where hoists were used irregularly. Lifting with hoists is slower than without aids, but the total extra time needed for their use is only 3–6% of the 8-hour work shift. Stooped and twisted trunk positions occurred less often when lifting aids were used than without an aid. However, some nurses worked in bad spine-loading positions, even when using lifting aids. To eliminate these postures from nursing work, more attention should be paid to working postures during the organised training of patient handling.