Cushioning pad for patient

Abstract

Cushioning pad for cushioning one or more body parts of a patient undergoing a therapeutic or diagnostic procedure, comprising: a first foam layer having a first unloaded thickness and a first compression stress value; and a second foam layer having a second unloaded thickness and a second compression stress value, wherein the first compression stress value and the second compression stress value are each expressed as a pressure required to compress the respective foam layer to 40% of its unloaded thickness in accordance with ISO 3386-1, characterized in that the first compression stress value is at least two times as large as the second compression stress value.

Description

[0001] P138219PC00

[0002] Title: Cushioning pad for patient undergoing procedure

[0003] FIELD

[0004] The invention relates to a cushioning pad for cushioning one or more body parts of a patient undergoing a therapeutic or diagnostic procedure, as well as to a system for performing a therapeutic or diagnostic procedure on a patient.

[0005] BACKGROUND

[0006] During a therapeutic or diagnostic procedure such as radiotherapy or diagnostic imaging, it is generally desired that a patient remains lying in a same stable position for a substantial period of time, in particular so as to facilitate spatial accuracy and precision in the procedure and avoid motion- induced disturbances. Thereto, the patient is typically positioned on a hard platform in a supine position, with at most a thin and soft matt between the platform and the patient. Unfortunately, this tends to cause locally excessive pressure on the patient’s body, which can then cause or exacerbate pain for the patient, especially in case the patient is seriously ill or frail.

[0007] SUMMARY

[0008] It is desired to reduce pain and increase comfort for patients undergoing a therapeutic or diagnostic procedure, in particular in a non- pharmacological manner and without hampering the procedure.

[0009] An aspect of the invention provides a cushioning pad for cushioning one or more body parts of a patient undergoing a therapeutic or diagnostic procedure. The cushioning pad comprises: a first foam layer having a first unloaded thickness and a first compression stress value; and a second foam layer having a second unloaded thickness and a second compression stress value. The first compression stress value and the second compression stress value are each expressed as a pressure required to compress the respective foam layer to 40% of its unloaded thickness in accordance with ISO 3386-1. The first compression stress value is larger than the second compression stress value, in particular at least two or more times as large as the second compression stress value. During use, the cushioning pad is to be positioned such that the second foam layer is between the first foam layer and the patient.

[0010] It has been found that, compared to the known practice as described in the background section, use of such a cushioning pad can reduce experienced pain intensity while maintaining positioning stability. Without wishing to be bound by theory, it is considered that the second foam layer having a relatively low compression stress value can provide an advantageous level of pressure relief for the patient, while the first foam layer having a relatively high compression stress value can at the same time provide an advantageous level of positioning stability. In particular, it is considered that the first foam layer due to its high compression stress value can inhibit undesired flexion of the cushioning pad, which flexion could otherwise affect positioning stability. Meanwhile, it is considered that the first foam layer due to its contribution to the overall thickness of the cushioning pad can provide a favorable conditioning stimulus with respect to the patient’s perception and experience of pain: the patient may subconsciously associate a larger pad thickness with a higher comfort level, especially when, due to the second foam layer, the patient experiences the pad as easily compressible, or ‘soft’, from the patient facing side of the pad.

[0011] A further aspect provides a system for performing a therapeutic or diagnostic procedure on a patient, comprising: a platform for supporting the patient thereon during the procedure; and a cushioning pad as described herein, wherein the cushioning pad is configured to be arranged between the platform and one or more body parts of the patient for cushioning the one or more body parts during the procedure. Advantages of such a system correspond to those described above with respect to the cushioning pad.

[0012] Optional advantageous elaborations of the above aspects are indicated in the below detailed description.

[0013] DETAILED DESCRIPTION

[0014] In the following, the invention will be explained further using examples of embodiments and drawings. The drawings are schematic and merely show examples. In the drawings, corresponding elements are indicated using corresponding reference signs. Although reference is made to the drawings for illustration, descriptions of embodiments herein can also be understood without reference to the drawings. In the drawings:

[0015] Fig. 1 shows a side view of a system comprising a cushioning pad;

[0016] Fig. 2 shows a transverse cross sectional view of the cushioning pad under compression from a patient;

[0017] Fig. 3A shows a plan view of the cushioning pad in unloaded state;

[0018] Fig. 3B shows a side view of the cushioning pad of Fig. 3A; and

[0019] Fig. 3C shows an end view of the cushioning pad of Fig. 3A.

[0020] Fig. 1 shows a system 20 for performing a therapeutic or diagnostic procedure on a patient P. The system 20 comprises a platform 21, in practice sometimes called a couch, for supporting the patient P thereon during the procedure and a cushioning pad 10 configured to be arranged between the platform 21 and one or more body parts of the patient P for cushioning the one or more body parts during the procedure. The platform 21 may be of a type known as such and may for example be slidably held on a base 22.

[0021] In embodiments, the system 20 is or comprises a radiotherapy system configured for performing radiotherapy on the patient P while: the patient is supported on the platform 21; and the cushioning pad 10 is arranged between the platform 21 and the one or more body parts of the patient P. Thereto, the system 20 may comprise a radiation source (not shown) for delivering ionizing radiation to the patient P, in particular using a beam emitted from outside the patient P. The system 20 may be configured to take one or more effects from the cushioning pad 10 on the radiation delivery into account, in particular with respect to control of the radiation source during the procedure.

[0022] In any case, to prevent excessive detrimental effect on radiation delivery, the cushioning pad 10 is preferably substantially transmissive to therapeutic ionizing radiation. In particular, the cushioning pad 10 may be configured to transmit therethrough at least 85% of therapeutic ionizing radiation, preferably at least 90%, more preferably at least 95%, even more preferably at least 97%, for example about 98% or about 99% or more. The transmission percentage of a particular cushioning pad may be determined experimentally as follows. The transmission is defined as the average of fived absorbed dose readings under radiotherapy reference conditions with the cushioning pad in the beam, divided by the average of five absorbed dose readings measured under radiotherapy conditions without the cushioning pad in the beam, multiplied by 100% to obtain the experimentally determined transmission percentage for the particular cushioning pad, where the absorbed dose is measured with a Farmer type ionization chamber. The radiotherapy reference conditions consist of a photon beam energy of 6 MV produced with a clinical linear accelerator, with a flattened field size of 10 cm x 10 cm, at 10 cm depth of water (and / or water equivalent material), at a source surface distance (SSD) of 90 cm, and 100 monitor units (MU) per measurement at a dose rate of 600 MU / min. The measurements should be performed in a water tank or phantom consisting of water equivalent material that extends along the central axis of the beam by at least 20 cm, and extends radially outwardly from the central axis of the beam by at least 20 cm in all radial directions. For the measurements with the cushioning pad in the beam, the cushioning pad is arranged directly on top of the phantom or adjacent to the phantom or water tank, such that the central axis of a radiation beam from the radiotherapy system intersects the cushioning pad at a central position with respect to the cushioning pad in a direction normal to the plane in which the phantom and the cushioning pad mainly extend.

[0023] Such an experimentally and / or otherwise determined transmission percentage may subsequently be taken into account in control of the same or a further radiotherapy system, in particular during radiotherapy treatment of patients having one or more body parts cushioned by the same or an equivalent cushioning pad, as shall be appreciated by the skilled person in the field of radiotherapy having the benefit of the present disclosure.

[0024] In embodiments, the system 20 is or comprises a diagnostic imaging system configured for performing diagnostic imaging on the patient P while: the patient is supported on the platform 21; and the cushioning pad 10 is arranged between the platform 21 and the one or more body parts of the patient P. Thereto, the system 20 may comprise one or more diagnostic imaging sensors (not shown), for example X-ray sensors, radiographic sensors, and / or ultrasound sensors. The system 20 may further comprise one or more emitters or generators (not shown) associated with the one or more sensors, for example X-ray emitters, magnetic field generators and / or ultrasound emitters. The imaging system may be or comprise: an X-ray imaging system, a computed tomography (CT) imaging system, a positron emission tomography (PET) imaging system, a magnetic resonance (MR) imaging system, and / or an ultrasound imaging system. The system 20 may be configured to take one or more effects from the cushioning pad 10 on the imaging into account, in particular with respect to control of the emitters and / or processing of sensor data from the sensors.

[0025] Figs. 2 and 3A-C show the cushioning pad 10 in more detail. The cushioning pad 10 comprises: a first foam layer 11 having a first unloaded thickness tl and a first compression stress value; and a second foam layer 12 having a second unloaded thickness t2 and a second compression stress value. The first compression stress value and the second compression stress value are each expressed as a pressure required to compress the respective foam layer to 40% of its unloaded thickness in accordance with ISO 3386-1. The first compression stress value is larger than the second compression stress value.

[0026] The use of foam in the cushioning pad 10 is generally compatible with therapeutic and diagnostic procedures such as radiotherapy and diagnostic imaging. As alluded to above, it is considered that any effects from the cushioning pad 10, e.g. attenuation of radiation, can be taken into account, e.g. compensated for, in control of the system if needed. However, in many cases, such effects may be negligible so that no adaptation in control of the system may be needed.

[0027] In embodiments, including in the shown example, the cushioning pad 10 comprises a cover 13, for example a closed sleeve, covering both the first foam layer 11 and the second foam layer 12. In this way, the foam layers can be protected and the pad 10 can be easily cleanable. Also, such a cover 13, in particular when opaque, can obscure the foam layers and the division therebetween, so that the patient P can visually perceive the cushioning pad 10 as a single unit having an overall thickness T. More generally, in embodiments, including in the shown example, the cushioning pad 10 is configured to obscure the division between the first foam layer 11 and the second foam layer 12. In Figs. 3B and 3C, a division between the layers 11 and 12 is indicated using a dashed line merely for clarity of the drawing and without implying visibility of such a division from outside the pad 10.

[0028] In embodiments, including in the shown example, the cushioning pad 10 is configured, in particular dimensioned, to cushion as the one or more body parts at least a torso of the patient P. In view thereof, in such embodiments, the cushioning pad 10 may be referred to, at least colloquially, as a mattress. In embodiments, including in the shown example, the cushioning pad 10 is configured, in particular dimensioned, to be positioned on the platform 21 without cantilevering from the platform 21, i.e. without extending beyond the platform 21 in plan view. In embodiments, the cushioning pad 10 has a length, i.e. a size along a length direction L, of at least 100 cm, preferably at least 110 cm, more preferably at least 120 cm, for example about 130 cm. In embodiments, the cushioning pad 10 has a length of at most 160 cm, preferably at most 150 cm, more preferably at most 140 cm, for example about 130 cm. In embodiments, the cushioning pad has a width, i.e. a size along a width direction W transverse to the length direction L, of at least 40 cm, preferably at least 45 cm, more preferably at least 50 cm, for example about 53 cm. In embodiments, the cushioning pad 10 has a width of at most 70 cm, preferably at most 60 cm, more preferably at most 55 cm, for example about 53 cm. In embodiments, including in the shown example, the cushioning pad 10 has a tapered shape in plan view, in particular at one end of the cushioning pad 10 that during use corresponds to a cranial end of a torso of the patient P.

[0029] In embodiments, with particular reference to Fig. 2 as illustration, the cushioning pad 10 is configured to cause the first foam layer 11 to remain substantially uncompressed and the second foam layer 12 to be at least locally fully compressed when the torso of an adult patient is on the cushioning pad 10 in supine position, in particular with the second foam layer 12 arranged between the patient P and the first foam layer 11. In this way, positioning stability can be promoted, in particular in view of the patient P essentially being supported by the substantially uncompressed first foam layer 11 at those locations where the second foam layer 12 is fully compressed. Thus, using the cushioning pad 10, positioning stability can be similar to when the patient P would lie directly on the platform 21, while at the same time the cushioning pad 10 can increase patient comfort, in particular by promoting a more homogeneous pressure distribution and a softer contact sensation for the patient using the second foam layer 12. These advantageous effects can be realized particularly well using the parameters indicated below.

[0030] In embodiments, the first compression stress value is at least two times as large as the second compression stress value, preferably at least three times as large, more preferably at least four times as large, for example at least 4.5 times as large.

[0031] In embodiments, the second compression stress value is at most 3.5 kPa, preferably at most 3 kPa, more preferably at most 2.5 kPa, even more preferably at most 3 kPa, for example about 1.5 kPa.

[0032] In embodiments, the first compression stress value is at least 3 kPa, preferably at least 4 kPa, more preferably at least 5 kPa, even more preferably at least 6 kPa, for example about 7 kPa.

[0033] In embodiments, the second unloaded thickness t2 is at least 1 cm, preferably at least 2 cm, for example about 3 cm. In embodiments, the second unloaded thickness t2 is at most 5 cm, preferably at most 4 cm, for example about 3 cm.

[0034] In embodiments, the first unloaded thickness tl is at least 1 cm, preferably at least 2 cm, for example about 3 cm. In embodiments, the first unloaded thickness tl is at most 5 cm, preferably at most 4 cm, for example about 3 cm.

[0035] In embodiments, the cushioning pad 10 has an unloaded overall thickness T that is at most 110%, preferably at most 105%, for example about 100%, of the sum of the first unloaded thickness tl and the second unloaded thickness t2.

[0036] In particularly preferred embodiments, the first compression stress value is about 7 kPa, wherein the second compression stress value is about 1.5 kPa, wherein the first unloaded thickness tl and the second unloaded thickness t2 are each about 3 cm, wherein the cushioning pad 10 has an unloaded overall thickness T of about 6 cm. Particularly favorable results have been obtained using such a combination of parameters, in particular with respect to both patient reported pain scores and preferences, as well as objectively determined positioning stability.

[0037] The foam materials of the first foam layer and the second foam layer are preferably elastic as opposed to viscoelastic, so as to prevent gradual sagging that could affect positioning stability. The foam materials may for example be or comprise polyurethane foam, in particular so-called high resiliency (HR) foam, and / or polyether foam. An example of a particularly suitable foam material for the first foam layer 11 is known in the field as RG40 HR foam, i.e. HR foam having a mass density (German: ‘Raumgewicht’, RG) of about 40 kg / m3. An example of a particularly suitable foam material for the second foam layer 12 is known in the field under the brand name EUCAFEEL® . It shall be appreciated that other suitable foam materials may be selected by the skilled person having the benefit of the present disclosure.

[0038] Although the invention has been explained herein using examples of embodiments and drawings, these do not limit the scope of the invention as defined by the claims. Within said scope, many variations are possible. For example, the cushioning pad may comprise one or more further foam layers or may be free of further foam layers, the cushioning pad may comprise one or more non-foam layers, and the first and second foam layers may or may not extend across the entire area of the cushioning pad in plan view. Additional patient positioning and / or cushioning devices, e.g. a head rest, arm rests, knee supports and / or foot supports, may be used during the procedure. A shape of the cushioning pad in plan view may be adapted to accommodate mechanical connections between such additional devices and the platform, e.g. for indexed positioning of such devices. Except where otherwise apparent, aspects, embodiments and options disclosed herein can be mutually combined. All such variants are considered included in the scope of the invention as defined by the claims. LIST OF REFERENCE SIGNS

[0039] 10. Cushioning pad

[0040] 11. First foam layer

[0041] 12. Second foam layer 13. Cover

[0042] 20. System

[0043] 21. Platform

[0044] 22. Base

[0045] L. Length direction P. Patient tl. First unloaded thickness of first foam layer t2. Second unloaded thickness of second foam layer T. Unloaded overall thickness of cushioning pad

[0046] W. Width direction

Claims

Claims1. Cushioning pad (10) for cushioning one or more body parts of a patient (P) undergoing a therapeutic or diagnostic procedure, comprising: a first foam layer (11) having a first unloaded thickness (tl) and a first compression stress value; and a second foam layer (12) having a second unloaded thickness (t2) and a second compression stress value, wherein the first compression stress value and the second compression stress value are each expressed as a pressure required to compress the respective foam layer to 40% of its unloaded thickness in accordance with ISO 3386-1, characterized in that the first compression stress value is at least two times as large as the second compression stress value.

2. Cushioning pad according to claim 1, wherein the second compression stress value is at most 3.5 kPa, preferably at most 3 kPa, more preferably at most 2.5 kPa, even more preferably at most 3 kPa, for example about 1.5 kPa.

3. Cushioning pad according to claim 1 or 2, wherein the first compression stress value is at least 3 kPa, preferably at least 4 kPa, more preferably at least 5 kPa, even more preferably at least 6 kPa, for example about 7 kPa.

4. Cushioning pad according to any of the preceding claims, wherein the first compression stress value is at least three time, preferably at least four times, more preferably at least 4.5 times, as large as the second compression stress value.

5. Cushioning pad according to any of the preceding claims, wherein the second unloaded thickness (t2) is at least 1 cm, preferably at least 2 cm, for example about 3 cm.

6. Cushioning pad according to any of the preceding claims, wherein the second unloaded thickness (t2) is at most 5 cm, preferably at most 4 cm, for example about 3 cm.

7. Cushioning pad according to any of the preceding claims, wherein the first unloaded thickness (tl) is at least 1 cm, preferably at least 2 cm, for example about 3 cm.

8. Cushioning pad according to any of the preceding claims, wherein the first unloaded thickness (tl) is at most 5 cm, preferably at most 4 cm, for example about 3 cm.

9. Cushioning pad according to any of the preceding claims, wherein the cushioning pad (10) has an unloaded overall thickness that is at most 110%, preferably at most 105%, for example about 100%, of the sum of the first unloaded thickness (tl) and the second unloaded thickness (t2).

10. Cushioning pad according to any of the preceding claims, wherein the first compression stress value is about 7 kPa, wherein the second compression stress value is about 1.5 kPa, wherein the first unloaded thickness (tl) and the second unloaded thickness (t2) are each about 3 cm, wherein the cushioning pad (10) has an unloaded overall thickness of about 6 cm.

11. Cushioning pad according to any of the preceding claims, configured to cause the first foam layer (11) to remain substantially uncompressed and the second foam layer (12) to be at least locally fully compressed when the torso of an adult patient is on the cushioning pad (10) in supine position, in particular with the second foam layer (12) arranged between the patient (P) and the first foam layer (11).

12. Cushioning pad according to any of the preceding claims, configured to obscure the division between the first foam layer (11) and the second foam layer (12).

13. System (20) for performing a therapeutic or diagnostic procedure on a patient (P), comprising: a platform (21) for supporting the patient (P) thereon during the procedure; and a cushioning pad (10) according to any of the preceding claims, wherein the cushioning pad (10) is configured to be arranged between the platform (21) and one or more body parts of the patient (P) for cushioning the one or more body parts during the procedure.

14. System according to claim 13, wherein the system (20) is or comprises a radiotherapy system configured for performing radiotherapy on the patient (P) while: the patient is supported on the platform (21); and the cushioning pad (10) is arranged between the platform (21) and the one or more body parts of the patient (P).

15. System according to claim 13 or 14, wherein the system (20) is or comprises a diagnostic imaging system configured for performing diagnostic imaging on the patient (P) while: the patient is supported on the platform(21); and the cushioning pad (10) is arranged between the platform (21) and the one or more body parts of the patient (P).

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