Antiseptics

After saline, the commonest type of lotion in use is an antiseptic. An antiseptic can be defined as a non-toxic disinfectant which can be applied to skin or living tissues and has the ability to destroy vegetative compounds, such as bacteria, by preventing their growth. If they are simply used to wipe across the wound surface they will have little effect. Antiseptics need to be in contact with bacteria for about 20 minutes before they actually destroy them (Russell et al., 1982). In some instances they can be applied in the form of soaks or incorporated into dressings, ointments or creams.

However, research using experimental wounds in the animal model have demonstrated antiseptics have toxic effects which need to be weighed against any advantages obtained from their use. In the late 1980s and early 1990s there was considerable debate about the use of antiseptics. Much of it centred round the use of Eusol, but all types of antiseptics were included. At one point the United Kingdom Central Council (UKCC) received at least one enquiry a week about accountability and the use of Eusol (Pyne, personal communication). Many nurses felt that they were failing their patients if they complied with medical instruction to use it. Doctors were at first bewildered that nurses were questioning their practice and then became more intransigent. Stories were rife that nurses were being disciplined for refusing to use Eusol. Doctors were said to be taking nurses from one ward and placing them on another to make sure that patients got their Eusol dressing. Many papers and letters were written on the topic supporting one view or the other and the subject was hotly debated at conferences. An example is a series of letters published in the British Medical Journal during 1992 which ranged from calling for clinical trials (Leaper, 1992) to recriminations against nurses who were accused of being too naive to see that they were being manipulated by the dressings' manufacturers (Coady, 1992).

After a while all the hype died away and the subject is now rarely discussed. A search in an electronic database revealed only one paper on Eusol in the last five years compared with 33 in the five years prior to that. Perhaps, as the level of evidence in respect of modern wound management products has increased, there is a greater willingness to put the role of antiseptics into perspective. Indiscriminate use of antiseptics is generally recognised as inappropriate. Healthcare professionals are increasingly aware that evidence is required to support the use of any antiseptic. It is no longer adequate for an individual to claim that anecdotal evidence of a 20-year period is all the evidence that is necessary. There is also a recognition that there may be a limited use for antiseptics in wound care. Each of the common antiseptics will be listed in turn and their advantages and disadvantages discussed.

Cetrimide

This is useful for its detergent properties - particularly for the initial cleansing of traumatic wounds or the removal of scabs and crusts in skin disease. It should not be used in contact with the eye. It is rapidly inactivated by organic material. Two dangers should be noted: it can cause skin irritation and sensitivity, and it is readily contaminated by bacteria, especially Pseudomonas aeruginosa. It is mostly only used in accident and emergency departments for initial cleansing of wounds rather than as a routine cleanser. It is available as a cream or as a lotion in combination with chlorhexidine. Morgan (1993) suggests that cetrimide should be used with caution in restricted circumstances rather than as a general cleanser.

Chlorhexidine

Chlorhexidine is used in a variety of aqueous formulations. It is effective against Gram-positive and Gram-negative organisms. Brennan et al. (1986) found that it has a low toxicity to living cells. Tatnall et al. (1990) undertook a similar study to identify the toxicity of several antiseptics when used on cultured keratinocytes (used for grafts). They found chlorhexidine to be the least toxic, but considered that antiseptics should not be used over these graft sites. Kearney et al. (1988) found that it could maintain its antimicrobial levels for a period of time when impregnated into a dressing. However, the efficacy of chlorhexidine is rapidly diminished in the presence of organic material such as pus or blood (Reynolds, 1982). Chlorhexidine is sometimes combined with cetrimide. Chlorhexidine seems to have little part to play in general wound care.

Hydrogen peroxide 3% (10 vols)

This has an oxidising effect which destroys anaerobic bacteria. However, it loses its effect when it comes in contact with organic material such as pus or cotton gauze.

The oxidising effect is also beneficial in removing slough from wounds. A study by Graber et al. (1975) found that hydrogen peroxide assisted in the rapid removal of slough, but, if it was used on a granulating wound, air blisters formed which burst and led to further breakdown of the wound.

Lineaweaver et al. (1985) showed that hydrogen peroxide was cytotoxic to fibroblasts unless diluted to a strength of 0.003%. This dilution is not effective against bacteria. O'Toole et al. (1996) found that even in concentrations 1000-fold less than 3% dilution it inhibits keratinocyte migration and proliferation. There is also a report of an incident where an air embolism occurred after irrigation with hydrogen peroxide (Sleigh & Linter, 1985). The use of hydrogen peroxide should be restricted to very sloughy wounds and it should never be used in cavity wounds. Some would also recommend limiting the number of applications or irrigating the wound with saline after use.

Hydrogen peroxide is also available in a stabilised form as a 1.5% cream. In this form the antiseptic action is prolonged.

Iodine

Iodine is a broad-spectrum antiseptic and is available in both an alcohol and an aqueous solution. The aqueous solution is used in wound care, usually as povidone-iodine 10% which contains 1% available iodine. It is used as a skin disinfectant and to clean grossly infected wounds. McLure and Gordon (1992) found it to be effective against methicillin-resistant Staphylococcus aureus. Several studies have questioned the value of using povidone-iodine. It is cytotoxic to fibroblasts unless diluted to 0.001%, retards epithelialisation and lowers the tensile strength of the wound (Lineaweaver et al., 1985). Brennan and Leaper (1985) found that povidone-iodine 5% damaged the microcirculation of the healing wound, but a 1% solution was innocuous. Becker (1986) reported that when operating on contaminated head and neck cases he irrigated 18 with povidone-iodine and 17 with isotonic saline. Some 28% of wounds became infected, all of which had been irrigated with povidone-iodine.

Povidone-iodine is also available in ointment, spray and powder form and impregnated into dressings.

Iodine should not be used for patients with thyroid disease or who have a sensitivity to the product.

Although iodine was one of the antiseptics that fell from favour at the beginning of the 1990s, it seems to be making something of a comeback. Gilchrist (1997) reported on the conclusions of a consensus meeting to discuss the role of iodine in wound care. The group comprised clinicians, scientists and representatives of industry and met under the auspices of the European Tissue Repair Society. After debating all the literature they concluded that there may be a role for iodine in the acute management of surgically drained abscesses and in clinically infected chronic wounds. Further research is still required to clarify the best formulation of iodine and how it can most effectively be used.

Potassium permanganate 0.01%

This is mostly used on heavily exuding eczematous conditions, mostly associated with leg ulceration. It is mildly deodorising and has slight disinfectant properties. It has been found to cause staining of the skin.

It is most easily used in the form of tablets. One tablet dissolved in four litres of water provides a 0.01% solution.

Proflavine

This has a mild bacteriostatic effect on Gram-positive organisms, but not on Gram-negative bacteria. There has been little research to demonstrate its value. Although it is available as a lotion it is mostly used as an aqueous cream. However, the proflavine is not released from the cream into the wound, so has no effect on the bacteria.

Silver nitrate 0.5%

Silver nitrate is rarely used as a lotion. It stains the skin black, and prolonged use causes hyponatraemia, hypokalaemia and hypocalcaemia. It is not recommended.

Sodium hypochlorite

This comes in several forms, the commonest being Eusol, Dakin's solution and Milton. It was originally used on heavily infected wounds during World War I. Dakin suggested that for it to be effective, it should be used in large volumes (Thomas, 1990).

Several research studies have been undertaken which suggest that the hypochlorite salts may have little beneficial effect and do much harm. Bloomfield et al. (1985) found that they cause irritation to both the wound and the surrounding skin; have a cumulative effect causing redness, pain and oedema; and prolong the inflammatory stage of healing. Sodium hypochlorite is cytotoxic to fibroblasts, unless diluted to a strength of 0.0005%, and retards epithelialisation (Lineaweaver et al., 1985). Brennan and Leaper (1985) found that it caused considerable damage to the microcirculation of the wound. The antiseptic effect is lost when it comes in contact with organic material such as pus or gauze. A study describing the use of Eusol and liquid paraffin on leg ulcers was undertaken by Daltrey and Cunliffe (1981). They found no significant evidence of antibacterial activity. Thomas (1986) found that about 100 ml of Milton were required to dissolve 1 g of yellow slough. He further calculated that, using ribbon gauze 2.5 cm x 1 m soaked in 5 ml of hypochlorite solution, about 100 dressing changes would be required to remove 5g of slough (Thomas, 1990).

Humzah et al. (1996) surveyed 124 plastic surgeons in the UK regarding their views on the use of Eusol. They had responses from 95 (77%) of the surgeons. Analysis of the responses found that 82% still used Eusol when it was available and the majority (88%) used it for sloughy wounds. The authors state that Eusol should only be used on dirty, sloughy wounds for a short period and never in clean wounds (i.e. granulating wounds). They go on to state that in view of the lack of controlled evidence against Eusol there needs to be an effective clinical trial. However, as Eusol is virtually banned in many places they suggest it may be too late.

It is also interesting to consider that where alternative modern products have replaced Eusol, it has not been missed at all. Humzah et al. (1996) also recognise that the plastic surgeons employed other methods as well for desloughing wounds. Overall, Eusol is an outmoded product whose disadvantages far outweigh any slight advantage there may be in its use.

4.4.2 Antibiotics

A range of antibiotics is available in topical form. They are potentially hazardous and they are not always absorbed into the wound. There is considerable risk of sensitisation to the patient as well as the development of resistant organisms. Systemic antibiotics are the treatment of choice when treating infected wounds because the infection may be too deep for topical antibiotics to penetrate.

D'Arcy (1972) recommends that any antibiotic that is used systemically should not be applied to the skin. However, antibiotics that are not appropriate for systemic use may be developed for use on the skin or in wound care. This means that creams, gels, ointments or impregnated dressings containing gentamicin, tetracycline, fusidic acid or chlortetracycline hydrochloride should not be used, as these antibiotics are used systemically. Neomycin is no longer used systemically, but topical use may cause systemic side-effects such as ototoxicity. One preparation which would seem to be of benefit in wound care is mupirocin.

Mupirocin is used predominantly for treating methicillin-resistant Staphylococcus aureus (MRSA) either in skin infections or in nasal colonisation. Several studies have demonstrated its efficacy in treating MRSA in burn wounds (Rode et al., 1989; Deng et al., 1995, Trilla & Miro, 1995). However, Cookson (1998) warns of the potential dangers of resistant bacteria. He cites a number of reported cases of mupirocin-resistant bacteria to support his arguments. He proposes that prolonged and widespread use of mupirocin should be stopped, and a more judicious approach to its usage be adopted.

This is the only completely safe cleansing agent and is the treatment of choice for use on most wounds. Manufacturers recommend it is used in conjunction with many of the modern wound management products. Saline is presented in sachets, small plastic containers that allow the saline to be squirted on to the wound and also in aerosols. These last two presentations are more widely used in the community.

4.4.4 Tap water

Tap water is being used more frequently on a variety of wounds. In particular, on areas already colonised such as wounds following rectal surgery or leg ulcers. Many patients may bath or shower prior to dressing change. There seems to be little point in then 'cleansing' the wound. However, the bath or shower should be thoroughly cleaned afterwards to avoid cross-infection. Hall-Angeras (1992) randomly allocated 617 patients with trauma wounds to either sterile saline or lukewarm tap water for wound cleansing. A significantly higher number of wounds cleansed with saline were infected compared with the tap water group. The authors suggest that this might be because of the profuse rinsing that could be achieved with tap water.

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Responses

  • KIM
    Can microorganisms grow on a wound that has been cleaned with eusol?
    21 days ago

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