A standard experimental 'chemical burn'.

To establish a standard method for producing experimental cutaneous injuries caused by contact with corrosive liquids, we modified an apparatus and method recommended by Walker and Mason in 1967 to produce experimental thermal burns. The resulting procedure proved to be safe, reproducible, humane and efficient and can be used with a wide variety of corrosive liquids.

Epidermal lipids and the natural history of hydrofluoric acid (HF) injury.

To explain several fortuitous observations, we hypothesized that there is a naturally occurring lipid 'barrier' to HF injury in guinea-pig skin and sought to characterize both the barrier and its role in the natural history of such injuries. Under anaesthesia, the dorsal trunk skin of groups of guinea-pigs was gently clipped of hair, washed with chloroform, soap and water, acetone or nothing (controls), and examined histologically for the presence of neutral lipid. Thereafter, in animal groups similarly washed, 1.5 in x 1.5 in (38 mm x 38 mm) areas were exposed to 40 per cent HF for up to 50 min and: (a) mean percentages of exposed areas with gross necrosis 5 days postinjury plotted on dose-response curves; or (b) less than 4 h after exposure to HF, intra-aortic India ink was injected and skin specimens examined to discern depth of ischaemia and necrosis. In contrast to controls, washing reduced neutral lipid in epidermis and significantly (at P < 0.001) increased susceptibility to injury by HF. With very rare (but interesting) exceptions, HF injury was found to be full thickness in depth with ischaemia and coagulative necrosis. In this study, development of guinea-pig skin necrosis due to HF was typically an 'all-or-nothing' 'barrier-penetration' phenomenon relating as much to the integrity of an epidermal lipid barrier as to the duration and intensity of noxious exposure.

Reduction of blood loss using tourniquets and 'compression' dressings in excising limb burns.

Excessive blood loss can limit the area of burn excised per sitting, lead to selection of en bloc rather than tangential excision, and increase the number of surgical procedures required per patient. Twenty-four burned extremities were studied to measure blood loss, complications, and effectiveness of a technique for tangentially excising burns of extremities using tourniquet hemostasis followed by application of steel-wool-pad 'compression' dressings before tourniquet release. An average of 7.3 days postburn (PB), a mean of 7% body surface area (BSA) burn was excised per extremity with a mean blood loss of 29 ml/% BSA burn excised (less than one fifth of recently published values). Graft take averaged 91%. There was no evidence of neurocirculatory injury or other complications. When applied as described and carefully monitored, hemostatic tourniquets followed by 'compression' dressings can safely reduce blood loss associated with the exclision of limb burns and allow larger areas to be excised at each operation.

Encouraging dialogue and autonomy in the burn intensive care unit.

Developing a systematic, rigorous approach to one major ethical issue--autonomous decision making by patients--as part of a standardized burn protocol ensures that the ill and injured persons we care for are given respect and a sense of control over their destiny. We cannot document a clinical, physiologic benefit to this particular approach but do find that early, frank discussions with patients, when combined with careful, active listening, help form strong care-giver-patient bonds. The patient's designation of a spokesperson to be consulted if the patient becomes unable to speak for himself prevents a great deal of anguish should the patient become comatose. The patient's wishes concerning limitations, if any, of maximal treatment are noted and respected. We believe that our approach is legally and ethically sound and can serve as one model for establishing informed consent in an intensive care setting.

ICU physician's ethical role in distributing scarce resources.

Of several schemes designed to ration scarce resources in the ICU, implicit rationing (i.e., by society at the macro level of resource input) and explicit rationing (i.e., by society at the level of bedside cost output) have the fewest ethical defects. The former (of which the British National Health Service is an example) threatens the traditional loyalty and honesty between physician and patient, and in the USA would probably transfer legal responsibility for any harm done by rationing from government to physician. The latter, structured in a form analogous to the American judicial system, identifies and leaves intact the respective responsibilities of state, physician, and patient, does not co-opt physicians into the bureaucracy, and encourages them to remain their patients' trustworthy advocates. As a basis for discussion, the public-policy statement offered above details at the macro and micro levels what is judged to be an ethically adequate position for the ICU physician facing this problem today.

Blisters, cooling, antithromboxanes, and healing in experimental zone-of-stasis burns.

To appraise the ability of each to improve wound healing in zone-of-stasis burns (i.e., burns becoming progressively more ischemic early postburn), 1) an antithromboxane (dipyridamol PO immediately postburn), 2) burn-wound cooling, 3) their combination, or 4) no treatment was administered to burned guinea pigs half of which had burn blisters removed immediately postburn (PB). In all groups with blisters removed whole-thickness or very deep partial-thickness skin loss occurred. In all groups with blisters intact complete reversal of ischemia occurred without necrosis and, while dipyridamol and cooling each diminished stasis early PB, only cooled wounds showed any improved retention of hair follicles at 3 weeks PB. In this model, therefore: 1) blister removal eliminated any therapeutic effect of cooling or dipyridamol; 2) in burns with blisters intact, absorbed heat appeared at least as detrimental to healing as stasis, and 3) some of the beneficial effects of cooling appeared unrelated to prevention of stasis.