Abstracts

type of hyperamylaseaemia in any patient. There was a statistically significant difference in amylase levels between the arterial and the external jugular venous blood confirming the salivary gland as the source ofthe extra amylase.

Amylase levels correlated well with the levels of consciousness and base excess and correlated signifi- cantly with the B glucuronidase levels indicating ab- normal permeability of the salivary gland cells as the source of the high serum levels of amylase found after acute carbon monoxide poisoning.

Takahashi M., Maemura K., Sawada Y. et al. (1982) Hyperamylaseaemia in acute carbon monoxide poisoning. J. Trauma 22, 3 Il.

Phenoxetol-chlorhexidine versus silver nitrate chlorhexidine Creams containing either 2 per cent phenoxetol plus 0.2 per cent chlorhexidine or silver nitrate and chlor- hexidine were tested as prophylactic agents against wound infection in patients with burns covering up to I .5 per cent of the body surface area. The acquisition ofbacteria was similar in the two treatment groups but the incidence of Staphylococcus aureus in the burns treated with phenaxetol-chlorhexidine was signifi- cantly lower. The incidence of Gram-negative bacilli was low in the two groups of patients and no wound yielded Pseudomonas aeruginosa. Unlike prepara- tions containing silver, phenoxetol-chlorhexidine did not cause electrolyte imbalance or stain materials with which it came into contact. The phenoxetol-chlorhex- idine did not appear to have any adverse effects.

Lawrence J. C., Cason J. S. and Kidson A. (1982) Evaluation of phenoxetol-chlorhexidine cream as a prophylactic antibacterial agent in burns. Lancer. 1, 1037.

Cortisol execretion The urine content of cortisol was measured in I9 patients with burns covering between 8 and 89 per cent of the body surface area. The urine cortisol content was supranormal for all the IO-day period of study. With the more severe injury (mean burned area=48,7 per cent) the maximal cortisol levels occurred 2 days after burning and correlated well with the extent of the burn. The urine cortisol levels also correlated signifi- cantly with the urine content ofcreatinine, magnesium and potassium and the sodium to potassium ratio.

Coombes E. J. and Batstone G. F. (I 982) Urine cor- tisol levels after burn injury. Burns 8, 333.

Gentamicin dosage and patient survival Optimal therapeutic serum concentrations ofgentami- tin were calculated from measurements of serum con- centrations in 66 patients with severe sepsis with Gram-negative organisms, and compared with the serum concentrations found in 39 patients, also with severe Gram-negative sepsis, who only received the recommended dosages of 3-5 mg gentamicin per kg body weight per day. In the 66 patients receiving indi- vidualized doses ofgentamicin the optimal therapeutic

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dose averaged 7.4 mg kg-1 d-1 whereas the conven- tional dose only averaged 4.4 mg kg-l d-l (P~O.001). An abrupt increase in the number ofsurviving patients from 33 per cent to 67 per cent occurred with the increased dosage of gentamicin.

Zaske D. E., Bootman J. L., Solem L. B. et al. (1982) Increased burn patient survival with individualized dosages ofgentamicin. Surgery91, 142.

ANIMAL STUDIES Changes in triglycerides and free fatty acids In guinea-pigs with deep bums covering 50 per cent of the body surface there is decreased lipolysis and decreased mobilization of free fatty acids and glycerol. Free fatty acid kinetics were studied using a constant rate of infusion of I4 C palmitate and 3 H glycerol. Free fatty acid turnover was decreased by 48 per cent and glycerol turnover was decreased by 48 per cent by 2 hours after burning. The free fatty acid to glycerol ratio decreased from I.87 to 1.43 (P<O.O2), suggesting that increased esterilication of free fatty acids con- tributed to the decrease in free fatty acid mobilization from adipose tissue following severe bums.

Robinson K. M. and Miller H. I. (1981) Contri- bution of altered lipolysis and re-esterification in per- turbations of free fatty acid kinetics during burn shock. Adv. Shock. Res. 5, 27.

Cortisone and alveolar macrophage activity Both burns and glucocorticoids are associated with the increased susceptibility ofthe burned host to pulmon- ary sepsis. Cortisol has been recommended for the treatment of inflammatory and oedematous con- ditions, particularly following respiratory injury. As high doses of cortisol given in viva impair both the functional and the metabolic activities of the alveolar macrophage it seems unwise to give cortisol to burned patients. Indeed the raised endogenously produced glucocorticoids may be the major cause of the reduced cellular defences of the lung.

This study in experimental animals showed that either a burn or a 7-day course of cortisone severely impaired (a 50 per cent reduction in 24 hours) both the functional activity and the number of phagocytic cells in the lungs. The 7-day cortisone treatment markedly elevated the plasma (over four-fold) and the lung lavage levels of cortisol (over two-fold). Twenty- four hours after burning the plasma levels of cortisol were significantly raised whereas the lung lavage corti- sol levels were not higher than found in saline treated sham-burn control animals. Following cortisone and burns the lung lavage concentrations of cortisol were increased over three-fold.

Gudewicz P. W.. Ferguson J. L., Kapin M. A. et al. (198 I) The effects of cortisone treatment and burn injury on plasma and lung lavage cortisol concen- trations and alveolar macrophage activity. Adv. Shock Rex. 5, 123.

Repigmentation of healing burns Repigmentation of healing partial- and full-thickness