TWM514854U - Negative pressure wound therapy apparatus - Google Patents

Description

Negative pressure therapy device

The present invention relates to a negative pressure treatment device, and more particularly to a negative pressure treatment device comprising a filler and an airtight unit.

Due to the increased awareness of health care, care for chronic wounds such as acne and ulcers has received much attention. Therefore, Negative Pressure Wound Theraphy (NPWT) devices that can non-invasively promote wound healing and reduce hospitalization are successively Development.

At present, the negative pressure treatment is to insert a filling material conforming to the shape of the wound in the wound, and the filling material has continuous holes, and then a pump is used to apply a negative pressure to the wound to derive the exudate of the wound and promote the growth of the new tissue. And improve local blood circulation.

Negative pressure therapy device of the conventional multi hydrophobic polyurethane foam is as filler [for example, Kinetic Concepts, Inc. (KCI Corporation) commercially available dressing black VAC® GranuFoam ^TM], which is fixed to maintain the shape of the vacuum therapy And structural strength. However, in order to fill an irregular wound, it is often necessary to cut and trim the shape of the filler a plurality of times, resulting in inconvenience to the medical staff. In addition, since the hydrophobic polyurethane foam has high adhesion to the wound, and the new tissue easily grows into its continuous pores, when the replacement filler is removed, the wound tends to be damaged and destroyed, which makes the patient feel Pain and cause the wound to hurt again.

Therefore, the object of the present invention is to provide a negative pressure treatment device which can keep the wound moist and absorb wound exudate without multiple cutting and dressing, and can effectively promote wound healing and avoid wounding when removing. Produces sticky damage.

Therefore, the novel vacuum therapy device comprises a filler and an airtight unit. The material of the filler is a hydrophilic polyurethane foam obtained by foaming a hydrophilic polyurethane and a foaming component, and the pores of the hydrophilic polyurethane foam are discontinuous closed pores, and the hydrophilic The polyurethane is a star block polyurethane obtained by reacting a first polyether polyol with a polyisocyanate, followed by reacting with a second polyether polyol and hyaluronic acid, the first polyether polyol Contains at least three terminal hydroxyl groups. The airtight unit overlies the filler material to form a wound space that is substantially sealed and contains the filler material.

The utility model has the advantages that the filling material formed by the hydrophilic polyurethane foam can absorb the wound exudate, and does not need to be cut and trimmed multiple times before being placed in the wound, and can effectively promote wound healing. And effectively avoid the damage that may be caused when removing the replacement.

The following is a detailed description of this new content:

The star-shaped structure of the star-shaped block polyurethane enables the polyurethane to have a large specific surface area to facilitate the water absorption property of the filler.

The closed pores of the hydrophilic polyurethane foam can avoid new life The risk of tissue growing into the wound during healing, reducing the damage that can result from removal.

Preferably, the novel vacuum therapy device further comprises a negative pressure unit coupled to the airtight unit to provide a negative pressure to the wound space.

Preferably, the hyaluronic acid has a weight average molecular weight ranging from 500,000 to 2,500,000. Hyaluronic acid having a weight average molecular weight higher than 2,500,000 is less favorable for promoting wound healing. In a specific embodiment of the invention, the hyaluronic acid has a weight average molecular weight of 1,000,000.

Preferably, the total of the first polyether polyol, the polyisocyanate, the second polyether polyol, and the hyaluronic acid is 100 mol%, and the content of the hyaluronic acid is in the range of 0.001 to 20 mol%. More preferably, the hyaluronic acid is contained in an amount ranging from 0.001 to 10 mol%.

Preferably, the polyisocyanate is an aliphatic polyisocyanate to avoid the risk of toxicity which may be selected from aromatic compounds. More preferably, the aliphatic polyisocyanate is selected from the group consisting of hexamethylene diisocyanatc (HDI), methylene dicyclohexyl diisocyanate (H ₁₂ MDI), isophorone diisocyanate. (isophorone diisocyanate, IPDI) or a combination thereof. In a particular embodiment of the invention, the polyisocyanate is hexamethylene diisocyanate.

Preferably, the first polyether polyol is poly(propylene glycol) triol (PPG triol).

Preferably, the second polyether polyol is polyethylene glycol (PEG).

In a specific embodiment of the present invention, the hydrophilic polyurethane is obtained by reacting poly(propylene glycol) triol with the polyisocyanate to form a star-shaped prepolymer, and then crosslinking with polyethylene glycol and hyaluronic acid. Star-shaped block polyurethane.

More preferably, the polyethylene glycol has a weight average molecular weight ranging from 1,000 to 6,000. If the weight average molecular weight of the polyethylene glycol is less than 1,000, biotoxicity is generated via metabolism; if the weight average molecular weight of the polyethylene glycol is more than 6,000, the operation of the crosslinking reaction may be difficult due to the high viscosity, but if Adding a solvent to lower the viscosity allows the solvent to remain on the filler and there is a risk of cytotoxicity.

Preferably, the foaming component comprises a blowing agent, water, a surfactant, a polyamine, and a catalyst. The polyamine is used to increase the mechanical strength of the hydrophilic polyurethane. More preferably, the polyamine is selected from the group consisting of 1,2-ethanediamine, 1,4-butanediamine, 1,6-hexanediamine, and three. Triethylenetetramine (TETA) or polyetheramine. The polyether amine selected from, but not limited to, produced by Huntsman JEFFAMINE ^®. The catalyst is used to catalyze the reaction of excess polyisocyanate with water to produce carbon dioxide. More preferably, the catalyst may be selected from zinc isooctylate, triethylene glycol diamine (TEDA, DABCO), dimethylcyclohexylamine (DMCHA). , dimethylethanolamine (DMEA), triethylamine (TEA), 1,8-dioxinbicyclo[5.4.0]undec-7-ene (DBU) or pentamethyldiethylenetriamine (PMDETA) ).

1‧‧‧Negative pressure therapy device

11‧‧‧Filling materials

12‧‧‧Airtight unit

13‧‧‧Wound space

14‧‧‧Negative pressure unit

2‧‧‧ Organization

Other features and effects of the present invention will be apparent from the following description of the drawings, in which:

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a cross-sectional side view showing a vacuum therapy apparatus of the present invention.

Before the present invention is described in detail, it should be noted that in the following description, similar elements are denoted by the same reference numerals.

The present invention will be further described in the following examples, but it should be understood that this embodiment is intended to be illustrative only and not to be construed as limiting.

<Preparation Example> Hydrophilic polyurethane foam PU _E

0.5 mol of PPG6000 triol (weight average molecular weight of 6,000) was mixed with 2.5 mol of HDI, and reacted at 80 ° C for 1 hour to obtain a star-shaped prepolymer, and then 0.85 mol of PEG 1000 (weight average molecular weight of 1,000) and 0.85 mol of PEG 2000 were added. The weight average molecular weight was 2,000) and 0.1 mol of hyaluronic acid (weight average molecular weight: 1,000,000), and the crosslinking reaction was carried out at 80 ° C for 6 hours to obtain a star-shaped hydrophilic polyurethane.

0.1 mol of sodium hydrogencarbonate (foaming agent), 0.4 mol of water, 0.5 mol of polydimethyloxane-polyoxyalkylene copolymer (surfactant), 0.1 mol of ethylenediamine and 0.1 mol of zinc isooctylate (catalyst, It is purchased from Taiwan Tin Sangjin Chemical Industry Co., Ltd., model TMG620) to obtain a foaming component, and then the above-mentioned star-shaped hydrophilic polyurethane is rapidly stirred and mixed with the foaming component to obtain hydrophilicity after foaming and forming. The polyurethane foam PU _E and the pores of the hydrophilic polyurethane foam PU _E are discontinuous closed pores.

<Example> Negative pressure treatment device NP _E

Referring to Fig. 1, the negative pressure treatment device 1 of the present embodiment is obtained by taking a hydrophilic polyurethane foam PU _E prepared in the above preparation example and placing it into a wound of a tissue 2, which is hydrophilic. The polyurethane foam absorbs the exudate of the wound and expands into a filler 11 conforming to the shape of the wound, and an airtight unit 12 is placed over the filler 11 to form a wound space 13 substantially sealed and containing the filler 11 . And a negative pressure is applied to the wound space 13 through a negative pressure unit 14 connected to the airtight unit 12, so that the exudate of the wound can be further extracted after being absorbed into the filling material 11, and the negative pressure of the embodiment is obtained. Treatment device NP _E .

In the present embodiment, the airtight PU unit 12 may be a sheet of appropriate modification (e.g., commercially available from 3M Tegaderm ^TM film); the pressure means is a PVC or TPU plastic tubes, and through the aspirator (FIG. Negative pressure is provided.

<Comparative example>

Polyurethane foam PU _C Comparative Example are commercially available from KCI VAC® GranuFoam ^TM dressing black, which is a hydrophobic polyurethane foam, and the continuous bore holes.

Negative pressure therapy device of Comparative Example NP _C is to the hydrophobic _C PU polyurethane foam filler after cutting to become consistent with the shape of a wound into the wound, and then to PU sheet (e.g. Tegaderm ^TM film) cover The rest are the same as the above embodiment.

[test] <Volume expansion rate measurement>

The method for measuring the volume expansion ratio of the present invention is as follows: 1 cm ³ (2 × 1 × 0.5 cm) of the polyurethane foam is immersed in deionized water, and after the volume is no longer changed, the polyurethane foam is taken out and Measure its volume (length, width, height, X cm ³ ). The volume expansion ratio of the polyurethane foam can be calculated according to the following formula.

The volume expansion ratios of the polyurethane foams PU _E and PU _C in the above Preparation Examples and Comparative Examples were measured, and the results are shown in Table 1 below.

As can be seen from the above Table 1, the hydrophilic polyurethane foam PU _E obtained in the above Preparation Example has a volume expansion ratio of about 227.5%; and the commercially available hydrophobic polyurethane foam PU _{C of the} comparative example hardly absorbs water at all. It is shown that the hydrophilic polyurethane foam PU _E prepared by the preparation of the present invention does not need to be cut to conform to the shape of the wound before being placed in the wound, which can facilitate the absorption of a large amount of wound exudate, and then expands to conform to the shape of the wound. The filler material is in close contact with the wound and can be correspondingly reduced as the exudate decreases during wound healing.

<Wound healing test>

A. Experimental animals:

The New Zealand white rabbit used in the following experiment is a male New Zealand white rabbit (8 weeks old, weighing about 2000-2500 g). All experimental animals were kept in a light and dark for 12 hours and at room temperature at 22 °C. And the relative humidity is maintained at 42% in an independent air-conditioned animal room, and moisture and feed are adequately supplied. Animals were given at least 2 weeks to adjust to the environment prior to the experiment. The feeding environment, treatment, and all experimental procedures for experimental animals are in accordance with the National Institutes of Health (NIH) Guide for the Care and Use of Laboratory Animals.

B. Sterilization of polyurethane foam:

The polyurethane foams PU _E and PU _C in the above Preparation Examples and Comparative Examples were sterilized by gamma-ray (dose of 40 kGy), and then subjected to the following experiment.

C. Formation of a full thickness skin wound:

The dorsal part of the New Zealand white rabbit was shaved and then disinfected with tincture of iodine and 70% alcohol. Thereafter, a full-thickness skin wound having an area of about 19.6 cm ² (circle of 5 cm in diameter) and a depth reaching the deep fascia was cut out from the back of the New Zealand white rabbit using a surgical knife.

D. Negative pressure wound treatment:

New Zealand white rabbits were randomly divided into an experimental group and two control groups (ie, control group 1 and control group 2), and each group of New Zealand white rabbits was formed according to the method described in item C above. Layer skin wounds. Next, full-thickness skin wounds in New Zealand white rabbits in the control group only one of Tegaderm ^TM film cover; the experimental group and control group of New Zealand rabbits full-thickness skin wounds using the above-described embodiments are 2 Examples and Comparative Examples The negative pressure treatment device NP _E and the negative pressure treatment device NP _C were subjected to negative pressure wound treatment (providing a negative pressure of 80 mmHg to the wound). During the experiment, the rabbits will be properly restrained to avoid the negative pressure therapy device falling off. The experiment was carried out for a total of 7 days, and the polyurethane foam was removed and replaced once a day for 8 treatments per day for 2 hours and 1 hour for each treatment, and 3 days after the negative pressure wound treatment. On the 7th day, the wound area of each group of New Zealand white rabbits was measured, and the results are shown in Table 2 below.

As can be seen from Table 2 above, on the 3rd and 7th day after the negative pressure wound treatment, the area of the full-thickness skin wound of the experimental group of New Zealand white rabbits was significantly reduced (at the 7th day) Narrowed to 16% before negative pressure wound treatment; while the skin wound area of New Zealand white rabbits in control group 1 was almost completely reduced; the area of skin wounds of New Zealand white rabbits in control group 2 was significantly reduced. slower (day 7 when reduced to about 49% of the negative pressure wound treatment before), a display device NP _E negative pressure therapy for wound healing in the experimental group compared with the control group having a negative speed means NP _C 2 treatment (including city The sale of hydrophobic polyurethane foam PU _C ) is even more significant.

In addition, since the hydrophilic polyurethane foam PU _E in the negative pressure treatment device NP _E of the present embodiment can be correspondingly reduced in the wound healing process as the exudate is reduced, and the closed pore can prevent the new tissue from being wounded. The growth enters during the healing process, and therefore, the wound is not adhered when the hydrophilic polyurethane foam PU _E is removed. The hydrophobic polyurethane foam PU _C in the negative pressure treatment device NP _C of the comparative example does not absorb the wound exudate when no negative pressure is provided, and the volume remains unchanged during the wound healing process, and when removed, Can not effectively prevent the wound from sticking.

In summary, the novel negative pressure treatment device can absorb the wound exudate by the filler formed by the hydrophilic polyurethane foam, and does not need to be cut to conform to the shape of the wound before being placed in the wound, and can effectively promote the wound. Healing, and by the closed pores of the hydrophilic polyurethane foam, and its corresponding shrinkage during wound healing, effectively avoiding the damage that may be caused when removing. Further, the raw material of the hydrophilic polyurethane foam of the novel negative pressure treatment device does not contain a monomer or a crosslinking agent which may be toxic, so that the object of the present invention can be achieved.

However, the above is only the embodiment of the present invention, and when it is not possible to limit the scope of the present invention, all the simple equivalent changes and modifications according to the scope of the patent application and the contents of the patent specification are still This new patent covers the scope.

1‧‧‧Negative pressure therapy device

11‧‧‧Filling materials

12‧‧‧Airtight unit

13‧‧‧Wound space

14‧‧‧Negative pressure unit

2‧‧‧ Organization

Claims (10)

A negative pressure treatment device comprising: a filler material made of a hydrophilic polyurethane foam, which is obtained by foaming a hydrophilic polyurethane and a foaming component, and the hydrophilic polyurethane foam The pore is a discontinuous closed pore, and the hydrophilic polyurethane is a star-shaped block polyurethane obtained by reacting a first polyether polyol with a polyisocyanate and then reacting with a second polyether polyol and hyaluronic acid. The first polyether polyol contains at least three terminal hydroxyl groups; and an airtight unit overlying the filler material to form a wound space that is substantially sealed and contains the filler material. The vacuum therapy device of claim 1, further comprising a negative pressure unit coupled to the airtight unit to provide a negative pressure to the wound space. The vacuum therapy device according to claim 1, wherein the hyaluronic acid has a weight average molecular weight ranging from 500,000 to 2,500,000. The negative pressure therapy device according to claim 1, wherein the hyaluronic acid is 100 mol% of the total of the first polyether polyol, the polyisocyanate, the second polyether polyol, and the hyaluronic acid. The content ranges from 0.001 to 20 mol%. The vacuum therapy device according to claim 1, wherein the polyisocyanate is an aliphatic polyisocyanate. The vacuum therapy device of claim 1, wherein the first polyether polyol is poly(propylene glycol) triol. The negative pressure treatment device according to claim 1, wherein the second polyether is The alcohol is polyethylene glycol. The vacuum therapy device according to claim 7, wherein the polyethylene glycol has a weight average molecular weight ranging from 1,000 to 6,000. The vacuum therapy device of claim 1, wherein the foaming component comprises a blowing agent, water, a surfactant, a polyamine, and a catalyst. The negative pressure treatment device according to claim 9, wherein the catalyst is selected from the group consisting of zinc isooctanoate, triethylenediamine, dimethylcyclohexylamine, dimethylethanolamine, triethylamine, 1,8- Diterpene bicyclo [5.4.0] undec-7-ene or pentamethyl diethylenediamine.