HAEMOSTATIC MATERIAL

Abstract

A haemostatic material that is effective at controlling the flow of blood from both standard and coagulopathic wound injuries that maintains a reduced compression time minimising the requirement for resuscitation fluids, and being easy and safe to use.

Claims

1. A haemostatic composition comprising a haemostat agent, a bioadhesive agent and an antifibrinolytic agent or derivative thereof.

2. A composition according to claim 1, wherein the antifibrinolytic agent comprises one or more selected from tranexamic acid, aminocaproic acid, aminomethylbenzoic acid, aprotinin, epsilon-aminocaproic acid and fibrinogen.

3. A composition according to claim 1, wherein the haemostat agent comprises one or more selected from oxidised regenerated cellulose, kaolin, gelatin, calcium ions, zeolite, collagen, chitosan or a chitosan salt.

4. A composition according to claim 3, wherein the haemostat agent comprises a chitosan salt.

5. A composition according to claim 4, wherein the chitosan salt comprises one or more selected from chitosan acetate, chitosan lactate, chitosan succinate, chitosan malate, chitosan sulphate or chitosan acrylate.

6. A composition according to claim 5, wherein the chitosan salt comprises lactate and/or chitosan succinate.

7. A composition according to claim 1, wherein the bioadhesive agent comprises one or more selected from a carbomer, polyvinyl alcohol (PVA), polyvinylpyrrolidone (PVP), 2-acrylamido-2-methylpropane sulfonic acid, or a high molecular weight acrylic acid polymer cross-linked with divinyl glycol or the salts of polyacrylic acid cross-linked with divinyl glycol.

8. A composition according to claim 7, wherein the bioadhesive agent comprises a cross-linked polymer of acrylic acid, the polymer having a molecular weight of at least about 50,000 g/mol.

9. A composition according to claim 8, wherein the bioadhesive agent comprises one or more selected from: a homopolymer comprising a polymer of acrylic acid cross-linked with allyl sucrose or allyl pentaerythritol; a copolymer comprising a polymer of acrylic acid and C.sub.10-C.sub.30 alkyl acrylate cross-linked with allyl pentaerythritol; and/or a carbomer homopolymer or copolymer comprising a block copolymer of polyethylene glycol and a long chain alkyl acid ester.

10. A composition according to claim 1, wherein the composition is applied to a carrier material.

11. A composition according to claim 10, wherein the carrier material is selected from a woven material, a non-woven material, a flexible substrate, a film, a foam, or a sheet gel.

12. A haemostatic composition according to claim 1 for use in stemming blood flow from a physiological target site.

13. A method of manufacturing a haemostatic composition according to claim 1, the method comprising the steps of combining a haemostat agent with a bioadhesive agent and an antifibrinolytic agent or derivative thereof.

14. A method according to claim 13, wherein the method comprises the steps of: (1) dispensing a pre-determined weight of a haemostat agent and optionally an inert material into a mixing vessel; (2) dispensing a pre-determined weight of a bioadhesive agent into the mixing vessel containing the haemostat and optional inert material; (3) dispensing a pre-determined weight of an antifibrinolytic agent or derivative thereof; and (4) mixing the haemostat agent, bioadhesive agent and antifibrinolytic agent or derivative thereof.

15. A method of haemostasis, the method comprising the steps of applying the haemostatic composition according to claim 1 to a physiological target site; and applying pressure to the haemostatic material.

16. A method according to claim 15, wherein the pressure is applied for no more than about one minute.

17. A carrier material comprising a haemostatic composition according to claim 1 applied to the carrier material.

Description

EXAMPLE 1

[0078] A 7 wt % bioadhesive agent (high molecular weight cross-linked polymers of acrylic acid (Carbopol 980NF)) and was blended with a chitosan derivatives/non-haemostatic chitosan blend. The chitosan derivatives consisted of chitosan lactate and chitosan tranexamate, whereby the chitosan was salted using combinations of chitosan, lactic acid and tranexamic acid. The mixture was double-coated onto viscose gauze at a coat weight of 45 gsm. This provided a haemostatic composition according to the invention.

In Vivo

[0079] To confirm that the invention exhibits real advantages in compression time, and provides evidence of efficacy with a total packing and compression time of 45 seconds, the composition of Example 1 was tested in a porcine model using a 6 mm femoral artery sever model as per the ISR model in both normal and coagulopathic conditions.

[0080] For normal conditions, a 6 mm sever was surgically made to the femoral artery of a porcine model. The artery was allowed to bleed out for a period of 45 seconds, following which the haemostatic material was applied to the bleed site, utilising a total combined packing and compression period of 45 seconds. Following the compression period, the wound was assessed for bleeding. If bleeding re-occurred, the haemostatic material compressed for a further one minute's pressure. Any re-bleeding after this point was classified as a fail.

[0081] For coagulopathic conditions, 25% of pig's blood volume was replaced with Hextend fluid (25% hemodilution) and hypothermia (core temperature 34-35 C.) was induced in the swine prior to arterial injury and hemorrhage. A 6 mm sever was surgically made to the femoral artery of a porcine model. The artery was allowed to bleed out for a period of 45 seconds, following which the haemostatic composition was applied to the bleed site utilising a total combined packing and compression period of 45 seconds. Following the compression period, the wound was assessed for bleeding. If bleeding re-occurred, the haemostatic material compressed for a further one minute pressure. Any re-bleeding after this point was classified as a fail.

[0082] The results demonstrated that 66% of the models treated under normal conditions and under coagulopathic conditions obtained haemostasis within the protocol in the femoral artery model within the initial period of 45 seconds. After a further one minute's pressure, 82% of the models treated under normal conditions obtained haemostasis within the protocol in the femoral artery model, whilst 83% of the models treated under coagulopathic conditions obtained haemostasis within the protocol in the femoral artery model.

[0083] Under normal conditions the current marketed Celox Rapid haemostat product, requires a protocol of care for 1 minute continuous compression followed by a further 1 minute compression (if required) to achieve haemostasis, whilst in coagulopathic conditions according to recent ISR results Celox Rapid requires 2 minutes continuous compression to achieve haemostasis.

[0084] In contrast, the composition of the invention is able to achieve haemostasis a majority of the time66% under both normal and coagulopathic conditionsin only 45 seconds, and 82% under normal conditions, and 83% under coagulopathic conditions after a further one minute's pressure. This represents a significant improvement, especially in a technical area where the time required to stem the bleeding from a wound is crucial, and can be the difference between life and death for a patient.

[0085] It is of course to be understood that the present invention is not intended to be restricted to the foregoing examples which are described by way of example only.