Abstracts 423

Leukotrienes in plasma and blister fluid Plasma and blister Ruid were tested for the presence of the leukotricncs LTB4 and LTC4 using radioimmuno- ;tssay tcchniqucs. In general the plasma levels were not elevated, and when there were transient high levels they could not be correlated with any change in clinical state. There were, however. high levels of LTB4 and LTC4 in burn blister fluid suggesting the participation of these arachidonic acid metaholites in the intlamma- tory reaction.

Dobke M. K.. Hayes E. C. and Baxter C. R. (1987) Leukotrienes LTB4 and LTC4 in thermally injured patients’ plasma and burn blister Ruid. J. Burr? Care Rehahil. 8, (3). 1x9-191.

C3a and C5a in plasma and blister fluid Plasma anaphylatoxins (C3a and C5a) were measured in I9 patients with a wide range of burned areas. Anaphylatoxin activity increased with increasing extent of injury, with a highly significant increase between burns covering IO-25 per cent and those with over SO per cent of the body surface area by 7 days after injury. Most of the patients (six of seven) with over SO per cent burns developed adult respiratory distress syndrome (ARDS) and four of the seven also had bacteraemia. In contrast, none of the patients with 10-25 per cent burns developed ARDS or bacteraemia.

Blister fluid contained high levels of C3a whereas CSa was present in blister fluid at about the same levels as in plasma. These high levels of C3a and CSa may have contributed to oedema formation and to the large numbers of leucocytes found in the burned tissues.

Bengtson A. and Heideman M. (1987) Anaphyhr- toxin formation in plasma and burn bullae Ruid in the thermally injured patient. Burrrs 13. (3). 185-189.

Fatal hydrofluoric acid injury Fatal refractory ventricular fibrillation followed a hy- drotluoric acid burn covering only 8 per cent of the body surface area as a result of the uncorrectable depletion of ionized calcium by the formation of cal- cium fluoride. It is essential that burns of this type should receive prompr subcutaneous injections of IO per cent calcium gluconate in doses sufficient to relieve local pain. Immediate excision of the wound can also decrease the body fluoride content and can be life- saving.

Mullett T.. Zoeller T., Bingham H. et al. (1987) Fatal hydrofluoric acid cutaneous exposure with refrac- tory ventricular fibrillation. J. Bum Cure Rchahil. 8. (3). 216-219.

Ceftazidime or tobramycin for Gram- negative infections In a comparison with the treatment of burn wounds infected with Gram-negative organisms. ceftazidime was found to be at least as effective as an aminoglyco- side. usually tobramycin. Eradication or reduction of organisms to less than IO per gram of burn wound biopsies was achieved in equal numbers of patients

treated with either drug. Similarly. resistant organisms appeared in two patients treated with ceftazidime and two treated with tobramycin. Side-effects with ceftazi- dime were minimal.

Stiver H. G.. Goldring A. M.. Snelling C. F. T. et al. (1987) Ceftazidime therapy versus aminoglycosidc therapy in patients with Gram negative burn wound infections. J. Bum Cure Rehahil. 8. (I). 19-22.

Colloid osmotic pressures of plasma and tissue fluid Colloid osmotic pressures (COP) of plasma and inter- stitial fluid from burned and non-burned skin were measured in tive patients with a wide range of burned areas (21-80 per cent) between 6 and S6 h after injury. A severe hypoproteinaemia was found in all patients with a concomitant reduction in plasma COP. Up to I2 h after injury the COP in burned skin Ruid was

higher th;m that in plasma. This inverted r;ttio grad- ually changed to ;I normal ratio (plasmrr COP>tissuc Huid COP) later than I2 h after injury. Such lindings sugpcsted that colloidal materials should not be infused until at least I2 h after injury.

Pitkanen J.. Lund T.. Aanderud L. et al. (19X7) Transcapillary colloid osmotic pressures in injured and non-injured skin of seriously burned patients. Z3wrf.s 13. (3), 198-203.

ANIMAL STUDIES

Silver-impregnated nylon cloth dressing In vitro studies showed that the silver ions derived from silver-impregnated nylon cloth were microbicidal against Smph. uweus. Psrudomonus umtginosu and Cudidu ulhicum. Physical studies of the cloth in con- tact with an aqueous gel showed a continuing release of ions as long as contact was maintained. Such ion release could be enhanced by passage of a small DC voltage through the cloth. In vivo the cloth was as effective us silver sulphadiazine in preventing colonization of the burn wound and was without the potential side-effects of it carrier cream.

Deitch E. A., Marino A. A., Malakanok V. et al. (1987) Silver nylon cloth: in vitro and in vivo evaluation of antimicrobial activity. J. Trauma 27. (3). 301-304.

Limitation of fibrin formation The role of fibrin formation in the vascular occlusion characteristic of zone of stasis burns was studied in rats with small (4cm’) burns. Such fibrin formation was

prevented in the burned animals by administration of ancrod. a pit viper venom with ;I trypsin-like proteinase which converts fibrinogen into a product which does not clot. In animals treated with ancrod before burning there wits a greatly reduced local vascular occlusion. It seems possible that the administration of an agent which prevents or rapidly destroys fibrin would lessen the tissue ischaemia seen in burned patients.

Ehrlich H. P.. McGrane W. L. and Rajaratnam J. B. M. (lYX7) Ancrod prevents vascular occlusion in thermally injured rats. J. Trcrcmo 27. (4). 420-424.