Periodic patient transfers are required to provide the necessary care for patients that are disabled or who need total care due to paralysis, old age, fracture, comatose condition, post-surgery or other conditions which limit the patient's mobility. Regardless of existing patient transfer devices, nurses in hospitals and long-term care facilities are still manually lifting the patient in and out of bed several times during an eight-hour shift in order to provide proper and necessary patient care. The common practice among nurses for transferring patients between a chair and a bed requires two or more nurses to lift a patient upwardly from a sitting position in a chair and transfer them into a hospital bed. Significantly, lifting a patient from a wheelchair to a bed or a bed to a wheelchair is one of the major causes of work-related injuries among nurses. Many times, lifting a patient has disabled a nurse permanently. Therefore, regardless of existing transfer devices, patients and nurses continue to suffer from a lack of adequate patient transfer devices.
The prior art includes several types of lifters and patient transfer devices to assist nursing care. However, these prior art devices suffer from a number of disadvantages. Thus, existing patient transfer devices are not being used as often as they should be to avoid injuries to hospital workers and to patients.
For example, U.S. Pat. No. 4,944,056, issued Jul. 31, 1990, to Schroeder et al., discloses a method and apparatus for transporting a disabled patient from bed to chair and back to bed. This device was adapted to engage both ceiling and floor, which is often not practical for use in hospitals or the nursing home environment. Although it can raise, lower and carry the patient, using a hoist mounted to the ceiling, it takes up significant space and is time consuming to operate. Moreover, it requires two separate pieces of equipment and may be expensive to maintain.
U.S. Pat. No. 3,137,011, issued Jun. 16, 1964, to Fischer, also discloses a complex patient transfer device with three pieces to perform the transfer. It needs a sling on which to suspend the patient, chains to attach the sling to a hoist and a chair on which to place the patient.
U.S. Pat. No. 5,060,960, issued Oct. 29, 1991, to Branscumb et al., discloses a wheelchair with a lifting device.
Patient handling mattresses are also known in the art which include at least two flexible material sheets, that together define a plenum chamber, with at least one sheet being perforated with small pinholes over at least a central surface area, and which open up directly to the interior of the plenum chamber. Such prior art mattresses are used by arranging the perforated sheet so that it faces an underlying fixed, generally planar support surface, such as a floor or table. When the mattress is charged with pressurized air, the escape of air under pressure through the pinholes acts initially to jack a load placed upon the mattress above the perforated flexible sheet, and thereby creates an air bearing of relatively small height between the underlying fixed, generally planar support surface and the perforated flexible sheet.
For example, in U.S. Pat. No. 4,517,690, issued to Wegener, an air pallet is disclosed that is formed from upper and lower thin flexible film sheets sealed at their edges to form a plenum chamber. Wegener's air pallet functions to move a load with minimal friction over an underlying generally planar fixed support surface. The bottom thin flexible material sheet is perforated by small diameter perforations such as pin holes at the load imprint area.
U.S. Pat. No. 5,561,873, issued to Weedling, provides an inflatable flexible pallet within which an array of structurally interrelated inflatable chambers are formed to support a load when inflated. The flexible pallet is configured to resist lateral and longitudinal shrinkage of the load support surface, as well as ballooning and hot dogging. Rotational instability is also reduced by providing a greater load surface support area.
U.S. Pat. No. 6,073,291, issued to Davis, provides an inflatable medical patient transfer apparatus that has a combination of transverse partition members and a raised perimeter section to reduce deleterious ballooning and uneven inflation as well as quick emergency deflation. Additional differentially inflatable patient rolling chambers are disclosed on the top of the transfer apparatus to provide assistance to medical personnel in beginning to roll patients reclining or lying upon the transfer apparatus, particularly in a deflated condition on a hospital bed.
Unfortunately, until now such patient transfer mattresses could not be effectively employed to transfer a patient to and from a chair.