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218 Burns

translocation of bacteria and/or toxins. As a result, the incidence of Table 33.4: Properties of topical antimicrobial agents.
sepsis is lower in enterally fed burn patients. Due to the high incidence Fibroblast
of gastric ileus in burn patients, nasoduodenal or nasojejunal tubes may Topical antimicrobial toxicity Bacteriocidal Bacteriostatic
be used for administration of feedings.
Despite the benefits, enteral feeding still carries significant risks, Sodium hydrochloride O 0.025%
with the potential for disastrous complications if not well managed, P 0.5%
including: Povidone Iodine P 1.0%
• mechanical complications (aspiration pneumonia, sinusitis, nasoa- 0.3% O
lar, oesophageal and gastric mucosal irritation and erosion, tube Hydrogen peroxide
lumen obstruction); 3.0% P
Acetic acid 0.25% O
• gastrointestinal (GI) complications, such as diarrhaea and faecal
impaction; and P 10.0%
Silver nitrate
• metabolic complications (dehydration, hyperglycaemia, hyper- or O 5.0%
hyponatremia, hyper- or hypophosphataemia, hypercapnia, hyper- P 1.0%
or hypokalaemia). Silver sulfadiazine O (with aloe
Pain Management vera/ nystatin) 1.0%
Burn injuries cause significant pain. Untreated, the pain exacerbates
the hypermetabolism. This pain can be constant, therefore requir-
preventing the development of invasive burn wound infection. However,
ing continuous analgesia, including the use of narcotics and sedative
by inhibition of the carbonic anhydrase enzyme, it may induce acid-base
agents. It is vital to provide adequate pain relief, especially during
derangements. It is also associated with pain on application, as well as
dressing changes, when ketamine may be useful. If narcotics are used
occasional hypersensitivity reactions (5–7% of patients).
for pain alleviation, the physicians must remember that tolerance may
Silver sulfadiazine as 1% suspension in a hydrophilic base
develop if therapy is prolonged. Sedation and analgesia should not
®
(Silvadene ) has essentially the same spectrum of activity as mafenide
be administered until hypoxia and hypovolaemia have been excluded
acetate, but fewer side effects. It is widely used in Africa as well as in
and/or treated because they both produce anxiety and disorientation in
the Western countries.
the patient. When given, they must be kept at an absolute minimum
Betadine is a water-soluble antiseptic, effective against a wide range
to avoid cardiopulmonary depression and to allow evaluation of the
of gram-positive and gram-negative organisms, as well as some fungi.
sensorium, an important indicator of adequate resuscitation. Analgesics
Clinical bacteriologic monitoring of the burn wound is imperative
should be given intravenously because intramuscular absorption is
in order to diagnose incipient burn wound sepsis and effect
erratic and unpredictable. Discontinuation of opiates should be antici-
immediate treatment.
pated and tapered as wounds heal.
Traditionally, topical antimicrobial agents have been applied to
Burn Wound Management a burn wound débrided of devitalised skin in a form of ointment,
The goals of local wound management are the prevention of viable cream, or solution. A secondary dressing should be applied to the burn
tissue desiccation and control of bacterial loads by use of topical anti- wound over the antimicrobial agent. These include: gauze, xeroform
microbial agents and/or biological dressings. (3% bismuth tribromophenate in a petrolatum-blend on fine gauze),
Second-degree wounds usually present as vesicular lesions that aquaphor gauze, foam dressings, and polyurethane dressings. These
should be punctured and the nonviable skin removed to allow for types of dressings are quite painful and, particularly in children,
the application of topical chemotherapeautic agents to the underlying associated with significant anxiety. Recent developments of new silver-
viable dermis. based antimicrobial delivery systems have eliminated the disadvantages
Topical Antibiotics of daily dressing change. Examples of available products include,
®
®
®
Several topical antimicrobial agents are available, as shown in Table among many: Acticoat , Aquacel Ag , Mepilex Ag , and Glucan
®
33.4. Modern antibacterial topical therapy for burn injuries was advo- Silver Matrix . These products consist of silver-containing pads or
cated by Moyer and co-workers in the early 1960s. They used aqueous hydrocolloid fibre sheets that provide a sustained delivery mechanism
silver nitrate 0.5% solution. for silver and in addition function to absorb excessive exudate from a
Silver nitrate is effective against most gram-positive organisms wound. Applied to the débrided wound surface, these products could be
and most strains of Pseudomonas, although it has limited left in place for several days.
effectiveness against other gram-negative bacteria, such as Klebsiella Tangential Excision
and Enterobacter. Silver nitrate (0.5%) soaks are also effective in The current accepted practice involves early excision (3–7 days post-
preventing microbial penetration of the eschar when treatment is begun burn)—tangential excision of deep second- and third-degree wounds
immediately after the burn. Because silver nitrate does not readily until viable tissue is reached, as evidenced by capillary bleeding.
penetrate the eschar, however, it has limited ability to control the Tangential eschar excision and skin grafting 3–5 days after the burn
proliferation of microorganisms already colonising the eschar. Soaks injury offers several advantages over full-thickness (fascial) excision,
of 0.5% silver nitrate are generally reserved for use in patients allergic such as removal of only necrotic tissue, salvage of injured tissue that
to sulfonamides. otherwise would have progressed to necrosis, preservation of biological
®
Sulfamylon was introduced in the mid-1960s, and is effective properties of the dermis, and prevention of contractures. The primary
against a wide spectrum of gram-positive and gram-negative organisms, closure is achieved by immediate grafting with autograft, and temporary
as well as anaerobes. Sulfamylon is an 11.1% suspension of mafenide closure is performed with heterograft or homograft, or synthetic barrier
acetate in a hydrophilic base. The solubility and the high activity of dressings. Although technically easy to perform, this procedure requires
mafenide against gram-negative organisms, particularly Pseudomonas experience in determining the level of adequate excision. The advantag-
aeruginosa, make Sulfamylon burn cream particularly effective in es are a shortened hospital stay and potentially improved function when
limiting the proliferation of bacteria that have penetrated the eschar and the wounds extend across joints. Tangential excision offers nothing if