256 Bums (1993) 19, (3), 256-257 Printed in Great Britain

Abstracts

CLINICAL STUDIES ANIMAL STUDIES

Serum calcitonin and inhalation injury Serum levels of immunoreactive calcitonin (iCT) were measured in 41 patients with bums, many of whom also had a smoke inhalation injury. Admission mean serum iCT levels were four times normal and reached 31 times normal by 24 h post injury. Although these levels did not correlate specifically with the extent of the burn, there was a very strong positive correlation with mortality. The correlation was highest in the patients who died soon after injury and lower in the later deaths. Of the patients who had clinical evidence of pulmonary injury, those who died had higher mean iCT levels than found in those who survived. There was a positive correlation between the serum iCT levels and the need for mechanical ventilation and the extent of pulmonary shunting.

O’Neill W. J., Jordan M. H. and Lewis M. S. (1992) Serum calcitonin may be a marker for inhalation injury in bums. J. Burn Care Wmbil. 13, (6), 605.

Early gut permeability and the extent of burns Polyethylene glycol 3350 was used in a study of the degree of abnormal gut permeability which occurred within 48 h in 14 patients with bums covering more than 20 per cent TBSA. Polyethylene glycol 400 was used as an internal control for abnormal motility and malabsorption. Enteral administration of both polyethylene glycols and their urinary excretion indicated that gut permeability of the larger molecule (PG 3350) was significantly increased early after injury. The patients excreted the same amounts of PG 400 as found in normal individuals given PG 400. The excretion of PC 3350 was positively correlated with the extent of the thermal injury.

Ryan C. M., Yarmush M. L., Burke J. F. et al. (1992) Increased gut permeability early after burns correlates with the extent of bum injury. Crif. Cure Med. 20, (II), 1508.

Non-invasive assessment of skin metabolism A non-invasive monitoring technique (Phosphorus 31 nuclear magnetic resonance) has been used to measure the temporal sequence of changes in severity and metabolism of healing bum wounds and full skin thickness flaps applied to excised wounds. The energy status of the wounds, which indicates the stage of development of a new microvascular network, is derived from the ratio of phosphocreatine to inorganic phosphate. Reductions in this ratio correlated with bum depth and improved over increasing time after injury. No decrease in intracellular pH was noted in the wounds. The phosphate shifts are probably due to tissue degrada- tion followed by tissue synthesis.

Schweizer M. P., Olsen J. J., Shelby J. et al. (1992) Non-invasive assessment of metabolism in wounded skin by 31P-NMR in vivo. 1. Trauma 33, (6). 828.

0 1993 Butterworth-Heinemann Ltd 0305-4179/93/030256-02

Enhancement of natural killer cell activity Studies in normal and burned rats (30 per cent TBSA) showed that the observed decrease in natural killer cell activity in burned animals can be enhanced by the administration of interleukin-2 or interferon to cultures of splenocytes from burned rats or intravenously into whole burned rats. The decreased natural killer cell activity may be due to a decrease in interleukin-2 production or availability. There does not appear to be an interleukin-2 receptor deficit.

Singh H., Abdullah A. and Hemdon D. N. (1992) Effects of rat interleukin-2 and rat interferon on the natural killer cell activity of rat spleen cells after thermal injury. J. Bum Care &hbif. 13, (6), 617.

Causes of pulmonary vasoconstriction A variety of haemodynamic parameters were measured in eight sheep receiving air containing 2 per cent carbon monoxide insufflated into their left and right lungs alternately for a total of 8 min. The carboxyhaemoglobin level reached 65 per cent and was associated with increases in cardiac output, pulmonary arterial pressure, stroke volume index and heart rate; a decreased systemic vascular resistance and unchanged pulmonary vascular resistance and mean arterial pressure. It appears that carbon monoxide does not have a direct pulmonary vasoconstrictive effect. The increased pulmonary arterial pressure is the result of the increased cardiac output and the decreased mixed venous oxygen content.

Theissen J. L., Loick H. M., Traber L. D. et al. (1992) Carbon monoxide and pulmonary circulation in an ovine model. J. Burn Care Rehabil. 13, (6), 623.

Treatment of HF dermal burns Histopathological analysis of wounds caused by 38 per cent hydrofluoric acid applied to the skin of anaesthetized pigs indicated that topical treatment with 2.5 per cent calcium gluconate and iced Hyamine and Zehiran soaks are the most effective means of reducing superficial epidermal damage. The injection of 5 per cent calcium gluconate or topical application of 10 per cent calcium acetate as a soak are more beneficial to deeper tissues of the dermis and subdennis.

Dunn B. J., MacKinnon M. A., Knowlden N. F. et al. (1992) Hydrofluoric acid dermal bums. An assessment of treatment efficacy using an experimental pig model. J. Ocncp. Med. 34, (9) 902.

Effective therapy of smoke-injured lungs Sheep with smoke-injured lungs received positive pressure ven- tilation (PPV) with positive end expiratory pressure (PEEP) either immediately after injury or after a delay during which hypoxaemia