Improvements in or relating to patient presentation

Abstract: In order to present patients in the correct position for surgical or investigative procedures and in order to reduce the time required to place on and remove from operating surfaces on which such procedures are carried out on patients, a wheelchair of novel configuration is described. The wheelchair has a seating arrangement comprising a back rest portion (10), a seat portion (14, 15) and foot rest means (18), adapted to receive a patient in a semi-recumbent or sitting position. The seating arrangement can be tilted so that the back rest portion is substantially horizontal and the seat portion is divided so that the patient's legs can be moved apart, while still supported, to present the patient's ano-genital region for surgical or investigative procedures.

Description: This invention relates to the presentation of patients for surgical and investigative procedures, especially but not solely for renal endoscopic procedures, and is particularly concerned with a wheelchair in which a patient can be sat and subsequently presented in a suitable position for a surgical or investigative procedure. The invention is also concerned with a surgical or investigative work station at which a surgeon may be seated and at which a patient in the wheelchair can be presented for a surgical or investigative procedure. While many surgical and investigative procedures involving the use of endoscopes inserted through a natural orifice or a percutaneous access site may take only a short time to conduct, a considerable amount of time is taken in removing the patient from a hospital trolley and placing him or her on an operating surface and then reversing this procedure at the end of the surgery or investigation. Indeed, up to 70% of the time may represent patient handling and only 30% is devoted to the surgical or investigative procedure. There are numerous designs of wheelchair which allow some posture adjustment of the patient. For example, WO84/02647 discloses a foldable wheelchair having a seating arrangement comprising a seat portion, a back rest portion lying at an obtuse angle to the seat portion and foot rest means, the seating arrangement being pivotally mounted on a wheeled frame, so that the back rest portion and seat portion may be moved to various positions relative the frame including a position in which the back rest portion is placed in a substantially horizontal position to present the patient's legs at a higher level than the patient's head. However, the known wheelchairs are not capable of adjustment to move a patient from a semi-recumbent position to present the patient in a position for ano-reno-genito surgical investigative procedure. According to one aspect of the present invention there is provided a wheelchair having a seating arrangement intended to receive a patient, the seating arrangement comprising a seat portion, a back rest portion lying at an obtuse angle to the seat portion and foot rest means, and wherein the seating arrangement is pivotally mounted on a wheeled frame, so that the back rest portion can be placed in a substantially horizontal position to present the patient's legs at a higher level than the patient's head, characterised in that the seat portion is constructed in three parts, comprising two outer portions to each of which a foot rest is attached and a central portion, the outer portions being movable outwardly away from the central portion about pivot axes located near the back rest portion and the central portion being pivotable downwardly about a horizontal axis, the arrangement being such that a patient can be received in the wheelchair in a semi-recumbent position and the seating arrangement can then be tilted to present the back of the patient in a horizontal position, whereafter the central seat portion can be pivotted downwardly and the outer seat portions pivotted outwardly so as to present the patient in a position for an ano-reno-genito surgical or investigative procedure. Each outer seat portion and an associated foot rest attached thereto may constitute a leg support portion with the attachment of the foot rest to the seat portion lying at an obtuse angle to the underside of the seat portion. Because the back rest portion and the foot rest attachment both lie at an obtuse angle to the seat portion, the position of the patient relative to these portions does not substantially alter when the patient is tilted from a normal semi-upright or rest position into the operative position. The obtuse angles which the back rest portion and foot rest attachment make with the seat portion will normally lie within the range of 100° to 140°. It may be desirable to make the back rest portion and foot rest means adjustable relative to the seat portion so that the angles and positions can be adjusted to accommodate patients of different sizes or proportions, but in most cases such adjustment will be unnecessary and a similar effect might be obtained, for instance, by placing a small cushion in the small of the patient's back. The arrangement and disposition of the wheels, by which the wheelchair is mobile, may take many forms. In one embodiment, a pair of large diameter wheels is mounted on an axle beneath the seat portion so as to constitute a wheeled frame and the wheels may have hand rings whereby the patient can propel the wheelchair. In this case, a stabilising wheel or wheels is or are provided and may conveniently be arranged on an arm which depends below the back rest portion and can be folded up to the back rest portion when the chair is tilted into the operative position. The arm, in its folded position, may act as a rest or stop holding the back rest portion in the substantially horizontal operative position or a separate rest or stop may be provided. In a preferred embodiment the back rest portion has attached to it a handle by which a hospital porter or nurse can move the wheelchair and this handle may act as a rest or stop for the backrest portion in the operative position. In another embodiment of the wheelchair, the chair portions are pivotally mounted on a wheeled undercarriage so that the chair can be tilted from the rest position to the operative position. Preferably means are provided for locking the chair in each of these positions. If the present chair is to be used in ano-reno-uro-genito-endoscopic procedures, it is necessary to present the patient to the surgeon with the legs of the patient wide apart and with a space between them so that the surgeon can approach the patient. To this end the outer seat portions and associated foot rests are pivotally mounted so that when the chair is in or being moved into the operative position the patient's legs can be parted. The wheelchair may be equipped with means for spreading the outer seat portions apart. The means for spreading the supports apart may be manually operated and include a hand lever or hand wheel, or in a more sophisticated embodiment a lever system may be provided for automatically spreading the outer seat ports apart as the wheelchair is moved from the rest position to the operative position. However, in this case it is desirable to have a manual override to prevent undue stress on elderly patients or patients with no or with restricted hip mobility. Since it is the intention that the present wheelchair will be used to wheel a patient from a ward or waiting area to an operating or investigating station, it is clear that the wheelchair will not be sterile. Nevertheless, it is important that the wheelchair and in particular the chair portion supporting a patient should be made of or covered with materials which are capable of withstanding washing with disinfectants. Preferably, the wheels and framework of the wheelchair are made of aluminium alloys or even stainless steel, and the chair portions are covered with rubber or plastics, which can be washed with disinfectants, even though the patient will normally sit on a washable or disposable cover laid on the chair. In the use of the chair, a patient is placed on the chair either in a hospital ward, or, if the patient is an ambulant day-patient, in a waiting area, and is then wheeled to an operating station. On arrival at the operating station, the wheelchair is tilted and the patient is presented to the surgeon in the correct position for an endoscopic surgical or investigative procedure to be carried out. At the end of the procedure, the chair is tilted back to the semi-recumbent rest position and wheeled away, whereupon the next patient can be wheeled up to the operating station so that there is no waste of the surgeon's time at the operating station. It will be appreciated that apart from operations and investigations conduct in the ano-genital area of a patient, similar endoscopic investigations and operations can be conducted at the head and chest of a patient. Of course, in conducting the latter procedures it is not necessary for the patient's legs to be spread apart and in consequence a simpler version of the wheelchair is suitable for such procedures. In an alternative embodiment of the wheelchair, the back rest portion, seat portion and a leg support portion or portions are mounted so that they can lie substantially flush with one another so as to provide a flat surface to receive a patient in a prone position. As just indicated, the purpose of the wheelchair is to present the patient at an operating station where operative and investigative procedures can be carried out. It is a further and concomitant object of the present invention to provide such an operating station. Accordingly, a further aspect of the present invention provides an operating station at which operative or investigative procedures can be carried out on a patient, comprising means to accommodate a surgeon in a sitting position, a work table in front of said means, a first work station to one side of said means for receiving sterile instruments and materials for use in an operative or investigative procedure, a second work station to the other side of said means for receiving used instruments and materials, and means for receiving the present wheelchair the work table and work stations being so shaped and located that when the wheelchair indicated above is wheeled up adjacent the station, the region of the patient to be operated on or investigated is presented at said work table. Thus, when the ano-genital region of a patient is to be operated on or investigated, that region will be presented at the work table and the surgeon will be seated with the patient's legs on each side of him, the work table being appropriately shaped to lie between the two leg supports of the wheelchair. In order to present the patient at the right height to the surgeon it may be necessary either to use a split-level operating theatre or to sit the surgeon in a well. However, a more convenient arrangement will be to provide a hydraulic or other lift to which the wheelchair can be firmly attached and then raised to the correct height for the appropriate procedure. With the present operating station and wheelchair, a surgeon sitting at the operating station can carry out a large number of operative or investigative procedures in a fraction of the time normally entailed in such procedures, most of which is represented by the time taken to remove the patient from a hospital trolley to an operating surface and back again. Thus with the present invention, the surgeons time is more usefully employed, as are expensive hospital resources, with a consequent reduction in hospital waiting lists. In order to enable the invention to be more readily understood, reference will now be made to the accompanying drawings which illustrate diagrammatically and by way of example some embodiments thereof, and in which:- Figure 1 is a side view of a patient in a wheelchair, Figure 2 is a perspective view of the seating part of another wheelchair, Figures 3 is a perspective view of a wheeled frame for supporting the seating part shown in Figure 2, Figure 4 is a side view showing parts of the wheelchair, Figure 5 is a front view showing parts of the wheelchair substantially in position for an investigative or operative procedure, Figure 6 is a perspective view of a detail of the wheelchair, and Figure 7 is a diagrammatic plan view of an operating station. The basic principle of the wheelchair of the present invention will first be described with reference to Figure 1 which is a diagrammatic representation of a patient in a wheelchair. The wheelchair shown in Figure 1 comprises a back rest portion 1, a seat portion 2 and two leg supports 3. The back rest portion 1 lies at an obtuse angle of about 130° to the seat portion 2 and the leg supports 3 also lie at an obtuse angle of about 130° to the seat portion. Because of these angles, the patient 4 is presented in the wheelchair in a semi-recumbent and relaxed position. The wheelchair has a pair of large diameter wheels 5 mounted on an axle 6 beneath the seat portion and the wheels may have hand rings whereby the patient can propel the chair, although these will generally be unnecessary. A stabilising wheel or wheels is or are provided for the wheelchair but not shown in the drawing. A stabilising wheel may be arranged on an arm which depends below the back rest portion and which can be folded flat against the back rest portion when the chair is tilted into an operative position, or stabilising wheels may be arranged on an axle mounted below the leg supports 3. The back rest portion 1 is provided with a handle 7 by means of which a hospital porter or nurse can hold the wheelchair to move it and the handle can act as a rest or stop in the operative position. In addition arm rests 8 for the patient may be provided. In the use of the wheelchair, the patient is placed in the chair or enters it by himself if ambulant and, after the administration of any necessary pre-operative medication, is wheeled to the location where the endoscopic procedure is to be carried out. The chair is then tipped so that the handle is on the ground, i.e. so that the broken line 9 is the ground. The patient is then presented in an appropriate position for the endoscopic procedure, with his head and back horizontal and his legs raised. The patient's legs can then be moved apart to permit the surgeon to operate. A practical version of a wheelchair in accordance with the invention will now be described with reference to Figures 2 to 6, in each of which various parts of the wheelchair are omitted for clarity. Referring now to Figure 2, there is shown the seating part of the chair, that is to say, the part for receiving a patient, this part being mounted on a wheeled frame shown in Figure 3, and a wheel and part of the frame being indicated in broken lines in Figure 2. The wheelchair comprises a back rest portion 10, the sides 11 of which are rounded outwardly to give side support to a patient. Two arm rests 12 are provided below the sides 11 and are shown in position to receive the arms of a patient sitting in the chair. Each arm rest 12 can be folded to lie flat against a board 13 forming part of a support structure for the back rest portion, the arm rests in their folded position lying flush with the lower part of the back rest portion. The wheelchair also has a seat portion which is divided into a central portion 14 and two side portions 15 each of which has an arcuate retaining board 16 to prevent the legs of a patient from slipping outwardly off the seat. Each side portion 15 has a square section bar 17 attached to it and each bar has a foot rest 18 mounted on it so as to be adjustable up and down. The bars 17 will normally extend forward of the seat portion with the foot rests raised above the ground. However, the bars are mounted beneath the side portions 15 so that they can be moved into a position where they extend substantially vertical so that the foot rests can be lowered into contact with the ground to assist the entry of a patient into the wheelchair. The back rest portion 10, the arm rests, the central and side seat portions and the foot supports are padded, where appropriate, and covered with plastics material capable of withstanding being washed with disinfectant. Conveniently, the plastics material may be one which simulates leather. In the use of the wheelchair, the bars 17 are moved into the position where they extend substantially vertical and the foot rests are lowered to the ground. A patient then enters the wheelchair and, when he is settled, the foot rests are raised to the correct level to accommodate his feet and the bars 17 are moved into their forward position in which they are then locked. The chair is wheeled to the operating theatre and the back and seat portions are turned so that the back rest portion 10 lies substantially horizontal and the arm rests 12 are folded flush with the back rest portion. The patient's legs are then swung outwardly by lowering the central seat portion and moving the side seat portions 15 with their bars 17 and foot rests 18 outwardly, the side seat portions 15 pivotting about axes at their outer edges adjacent the back rest portion. The patient is thus presented in the correct position for a surgical or investigative procedure in the ano-genital region. At the end of the procedure, the side seat portions 15, bars 17 and foot rests 18 are swung back to their original position and the central seat portion 14 is raised and locked in position. The chair is then moved to raise the patient from a recumbent position to an upright sitting position and the patient is wheeled away. The mechanisms by which the movements of the various portions of the wheelchair can be achieved are on the whole standard mechanisms which have been adapted for their particular purpose in the wheelchair. These mechanisms and their operation will now be described with reference to Figures 3 to 6. Figure 3 shows a wheeled frame for the wheelchair. The frame comprises two substantially D-shaped side members 20 which are joined at the bottom and near the top of the upright portions of the side members by cross-members 21 and 22 and at the bottom by a substantially A-shaped member 23 the apex of which also connects with the lower cross-member 21. At their forward ends the side members 20 have support discs 24 which support stub axles for spoked wheels 25. Outrigger rods 26 attached to the upright portions of the side members 20 carry at their lower ends castors 27 which have foot-operable brake elements 28. At their uppermost regions, the side members 20 have discs 29 secured thereto and two arms 30 are pivotally mounted on the discs and hang downwardly. The arms 30 are joined by a member, indicated at 31, which is joined to the support structure for the back rest portion, so that the arms 30 swing relative to the discs as the seat is swung from the upright to the recumbent position. Figure 4 shows the mechanism by which the chair can be swung and locked in different positions and the mechanisms for enabling the arm rests 12 to be folded and the foot rests to be adjusted. The frames 20 and the member 23 support a cross-beam 32 which has two L-shaped brackets 33 fixed to it in opposition to one another. The brackets define between them a space in the mid-plane of the wheelchair and a quadrant 34 is held securely between the brackets, the quadrant being formed with rectangular recesses 35. The quadrant could also be formed with ratchet teeth. A wooden support structure for the back rest portion 10 includes two triangular wings 36 which are spaced apart and which are joined at their lower ends by a base board 37 (c.f.Figure 5). Beneath the base board is a cruciform member 38 one arm 39 of which carries a spring-loaded detent 40 engaging in one of the recesses 35. The detent 40 can be moved out of a recess against the action of the spring loading by a cable connection 41, the cable being operable by a hand lever 42. The hand lever 42 is mounted on a handle 43 by means of which a porter or nurse can move the chair. When the hand lever 42 is operated to move the detent 40 out of a recess 35. The chair comprising the back rest, seat and leg portions can be swung on the arms 31 and, if the lever 42 is then released, the chair will swing until the detent encounters the next recess 35 whereby the chair will be locked in this position. As indicated in Figure 2, the boards 13 are formed with slots 44 and support bars 45 pivotally attached to the undersides of the arm rests 12 pass through the slots where they are held by the engagement of a bayonet slot 46 and a rod (not shown). In order to fold the arm rests flat, the bars 45 are lifted to disengage the bayonet slots and then passed through the slots 44 to allow the arm rests to lie flush against the boards. Each square section bar 17 is formed on its underside with holes 47 (c.f. Figure 5) and each foot rest 18 has attached to it a locking mechanism 48 which comprises a spring-loaded pin engaging in a hole 47 in the bar 17 and thus locking the foot rest in position. A handle 49 of the locking mechanism can be operated to retract the pin and allow the foot rest to be moved up or down the bar to adjust the foot rest to the required position for a patient. Beneath each side seat portion 15 is a support structure of bars which extend below the base board of the wooden support structure. One of these bars 50 for each side seat portion carries a hand lever 51 for another cable which operates means for releasing the respective side seat portion 15 and allowing it to be swung out. Figure 5 shows these means but with the hand lever 51 omitted for clarity and with the central seat portion 14 swung upwardly instead of hanging down. Each side seat portion 15 has mounted beneath it a hollow beam 52 within which is a spring-loaded rod, acting as a detent, the pointed end 53 of which engages in a toothed quadrant 54, two such quadrants being mounted below the base board 37. Operation of the hand lever 51 causes the rod to be retracted from engagement with its quadrant 54 allowing the side seat portion 15 and foot rest 18 to be swung into the open position shown. Underneath the central seat portion 14 there is a cruciform member 55 which is held in place by a central pivot 56 and which has two arms 57 which project beyond the seat portion 14 to engage in U-section brackets 58 on the underneath of the side seat portions 15, so as to lock the seat portions 14 and 15 together. To unlock the seat portions, the cruciform member is pivotted into the position shown in broken lines. The underneath of the central seat portion is also provided with stops 59 and 60 to limit the movement of the member 55 and with guideways 61 for the ends of the other two arms. The square section bars 17, on which the foot rests 18 are mounted, are normally held in the forward position shown in Figure 4 by the engagement of a recess in a bar 62 in a bolt projecting through the bar 17, the bar 62 being urged into such engagement by a spring 63. By disengaging by hand the bar 62, the bar 17 can be moved into the vertical in Figure 4 to facilitate entry into the wheelchair as already described. In operative procedures carried out under anaesthetic where the patient is in a recumbent position, it would be desirable in an emergency to be able to lower the patient's head below the rest of his body so as to prevent, for example, the patient from swallowing or inhaling his own vomit. A frame comprising two uprights 64 and a cross-beam 65 is pivotally mounted to the rear of the two D-shaped side members 20 as shown in Figure 6. The frame is normally held in the position shown by a spring 66. When the wheelchair is in the recumbent or operating position, the back of the back rest portion will rest against the upper ends of the uprights. However, in an emergency an anaesthetist can grab the cross-beam 65 and pull it against the action of the spring 66 thereby pivoting the uprights 64 about their pivotal connections 67 to the members 20 and lowering their upper ends. This allows the back rest portion to pivot to lower the head of the patient and the pivotal movement may be as much as 15°. It is to be appreciated that many modifications of the wheelchair and its construction are possible and that alternative mechanisms to those described can be provided for moving or permitting movement of the various parts of the seating arrangement. For example, the wheels 25 could be replaced by castors similar to the castors 27, or the wheelchair could be provided with two separate handles for pushing the chair, with the various hand levers for moving the parts of the seating arrangement and for braking mounted on the handles. While the wheelchair has been shown as having hand levers for moving or permitting movement of the various parts and mechanisms of the wheelchair, it will be appreciated that the various mechanisms can be electronically controlled and in such a case a panel of push buttons or the like will be placed on the handle or in another convenient location. As clearly shown in Figure 2, the back rest portion 10 has at its upper end an integral portion against which a patient's head can rest. In a further modification of the wheelchair, this head rest portion can be movable and pivotable about an horizontal axis, there being means to lock the head rest portion in a pivotted position. This enables a patient's head to be raised or lowered (extended), particularly when the patient is in a prone position. In addition, in a further modification of the wheelchair it is possible to pivot the whole of the seat portion relative to the back rest portion and to move the bars 17 and foot rests 18 so as to provide a flat surface to receive a patient in a prone position. As indicated above, the wheelchair is particularly suitable for presenting a patient at an operating station at which an operative or investigative procedure can be carried out endoscopically on a patient. Such an operating station is shown very diagrammatically in Figure 7 and comprises means 70 for accommodating a surgeon in a sitting position with a work station on each side, one for receiving or holding sterile instruments and materials for use in an operative or investigative procedure and the other 72 for receiving used instruments and materials. A work table 73 is provided in front of the surgeon and there is a wheelchair-receiving region 74 at which is means 75 for accommodating an anaesthetist. The arrangement of the seating means, work table and work stations is such that when the wheelchair is brought up to the operating station, the region of the patient to be operated on or investigated is correctly presented at the work table. To this end it may be necessary to seat the surgeon in a well, or to arrange for the wheelchair to be raised either by wheeling it up a ramp to a level position or by elevating the wheelchair as by means of a hydraulic lift. In each case, means is provided for locking the wheelchair adjacent the work table.

Claims: A wheelchair having a seating arrangement intended to receive a patient, the seating arrangement comprising a seat portion (14, 15), a back rest portion (10) lying at an obtuse angle to the seat portion and foot rest means (18), and wherein the seating arrangement is pivotally mounted on a wheeled frame, so that the back rest portion (10) can be placed in a substantially horizontal position to present the patient's legs at a higher level than the patient's head, characterised in that the seat portion is constructed in three parts, comprising two outer portions (15) to each of which a foot rest (18) is attached and a central portion (14), the outer portions (15) being movable outwardly away from the central portion (14) about pivot axes located near the back rest portion (10) and the central portion (14) being pivotable downwardly about a horizontal axis, the arrangement being such that a patient can be received in the wheelchair in a semi-recumbent position and the seating arrangement can then be tilted to present the back of the patient in a horizontal position, whereafter the central seat portion (14) can be pivotted downwardly and the outer seat portions (15) pivotted outwardly so as to present the patient in a position for an ano-reno-genito surgical or investigative procedure. A wheelchair as claimed in Claim 1, wherein the wheelchair has arm rests (12) for a patient's arms when the patient is in the semi-recumbent position, and wherein the arm rests (12) can be folded to lie substantially in the plane of the back rest portion. A wheelchair as claimed in Claim 1 or 2, wherein a quadrant (34) is mounted below the seating arrangement and is formed with recesses (35) or teeth to receive a spring-loaded detent (40) mounted on the seating arrangement, and wherein means is provided for moving said detent against the spring loading to remove the detent from engagement with a recess or the teeth to permit the seating arrangement to pivot. A wheelchair as claimed in any one of Claims 1 to 3, wherein a toothed quadrant (54) for each outer seat portion (15) is mounted on the frame and the end of a spring-loaded rod (53) or detent member engages between the teeth of the quadrant, and wherein means (51) is provided for moving said rod or detent member against the spring loading to remove the rod or detent member from engagement with the teeth to permit each outer seat portion to pivot. A wheelchair as claimed in any one of Claims 1 to 4, wherein the foot rests means comprises two foot rests (18) each of which is supported from its appropriate outer seat portion and is adjustable relative thereto. A wheelchair as claimed in any one of Claims 1 to 5, wherein support means (64) are provided for supporting the head end of the back rest portion when the latter is lying substantially horizontal, and wherein said support means are pivotally mounted (67) and held in place under spring action (66), the support means being movable by hand to permit the head of a patient to be lowered. A wheelchair as claimed in any preceding claim, wherein the back rest portion, the seat portion and leg support portions are mounted so that they can be moved to provide a flat surface to receive a patient in a prone position. An operating station at which operative or investigative procedures can be carried out on a patient, comprising means (70) to accommodate a surgeon in a sitting position, work table means and patient receiving means, characterised in that the work table means comprises a work table (73) in front of said means to accommodate a surgeon, a first work station (71) to receive sterile instruments and materials, a second work station (72) to receive used instruments and materials, the work stations (71, 72) lying on either side of the means (74) to accommodate a surgeon, means for receiving a wheel chair and a wheel chair as claimed in any preceding claim, said receiving means, work stations and work table being so shaped and located that when the wheel chair is wheeled into said receiving means, the region of the patient to be operated on or investigated is presented at said worktable.

Inventors: MILLER RONALD ALAN, WICKHAM JOHN EWART ALFRED, MILLER, RONALD ALAN, WICKHAM, JOHN EWART ALFRED
Applicants: KEYMED MEDICALS & IND EQUIP, KEYMED (MEDICAL & INDUSTRIAL EQUIPMENT) LIMITED
Application year: 1989
Main classification: A61G5
IPC codes: A61G5, A61G15