Wound dressings test methods

Knitted fabrics used for medical applications - such as in wound dressings - require a zone of inhibition. These may be studied using the AATCC 147 Parallel Streak Standard Method this is an appropriate semi quantitative method for evaluating the antibacterial activity of diffusible antimicrobial agents on treated fabrics. A test result for a fabric treated with the silver salt suspension and a control fabric is presented in Rg. 5.5, where the tested bacteria was Staphylococcus aureus. 

There are some standard testing methods for medical devices, which may be related to wound dressings in ASTM these include general practice for medical devices, analysis of medical materials, methods for medical packages, " fluid penetration,sterilisation, and disinfection. ... 

BS EN 13726-1 2002. Test methods for primary wound dressings. Part 1. Aspects of absorbency. 

BS EN 13726-3 2003. Test methods for primary wound dressings. Part 3. Waterproofness. BS EN 13726-4 2003. Test methods for primary wound dressings. Part 4. Conformability. BS EN 13726-5 2003. Test methods for primary wound dressings. Part 5. Bacterial barrier properties. 

Wound dressing specifications are generally registered under European Pharmacopoeia (EA) and British Pharmacopoeia (BP). BS EN 13726 Parts 1—8. (Nonactive medical device) test methods for primary wound dressing. BS EN 13726 has several subsections, as listed below ... 

At the Surgical Material Testing Laboratories (SMTL), (Cardiff, UK) Thomas et al. also carried out a number of researches to develop suitable test methods for the wound dressings (Thomas, 1997, 2009 Thomas, Hughes, Fram, Halllet, 2005 Thomas McCunnin, 2003). 

The absorbency of wound dressings is determined by using BS EN 13726-1 2002, 3.2 free swell absorptive capacities. This is also known as BP method. For this test, 5 X 5 cm dressing specimens were prepared. The test solution A (2.298 g sodium chloride and 0.368 g calcium chloride dihydrate is added to 1 L of distilled water) is prepared for the experimental studies. The solution A is warmed to 37 1°C, and then 40 times the mass equivalent of the specimen is dispensed slowly and gently onto the specimens in the Petri dishes. The Petri dishes are then placed in an incubator for 30 min at 37 1°C (body temperature). After 30 min of conditioning, the dishes are removed from the incubator, suspended by one corner by using tweezers to allow excessive solution to drip off for 30 s, and reweighed for wet mass. 

Method The test specimens of size 5 x 5 cm (0.5 g) are taken from the centre of the dressings, and their effect on the pH of two different solutions was determined. The fluids used in this smdy are distilled water and the test solution A (2.298 g sodium chloride [NaCl], 0.368 g calcium chloride [CaCl2] dihydrate added to 1 L of distilled water). In order to simulate the different mechanisms of exudate production, both from highly exuding wounds and slowly exuding wounds, two different methods for dosing the fluid with the dressings are used ... 

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