Annals of the MBC - voL 3 - n' 4 - December 1990

INTERNATIONAL ABSTRACTS

USE OF CULTURED HUMAN KERATINOCYTES FOR ALLOGRAFTING BURNS AND CONDITIONS FOR TEMPORARY BANKING OF THE CULTURED ALLOGRAFTS

The therapy of extensively burned patients is made more difficult by the limited amount of donor skin available for grafting. In an attempt to overcome this shortage, epidermal keratinocytes were cultured from the foreskins of healthy newbom boys requiring circumcision. The resulting epithelia were used as allografts in five children suffering from deep partialand full-thickness burns. The patients were all received in the Bum Unit some 20 days after injury, with the bums open and infected. Before grafting the wounds were treated with Silvadene cream until the recipient tissue was clean and non-septic. The wounds thus grafted with the allogeneic cultured epithelium healed after 10-15 days. The conditions are also described for the setting-up of banks for the cultured epidermis in order to have allografts available for early wound closure as required.

Bolivar-Flores J., Poumian E., Marsch-Moreno M., Montes de Oca G., Kuri-Harcuch W. Burns, 16: 3-8, 1990.

EFFECT OF PROSTAGLANDIN E IN MULTIPLE EXPERIMENTAL MODELS. VII. EFFECT ON RESISTANCE TO SEPSIS

The immunosuppression seen following thermal injuries is one of the main reasons for the high infection rate in burned patients. One possible explanation of the immunosuppression is the elevated prostaglandin E (PGF) level. To test this hypothesis, multiple mouse models were used to evaluate the effect of these high PGE levels on susceptibility to infectious complications. It was found that the administration of 100 ltg/kg of the long-acting derivative of PGE, 16,16-dimethyl-prostaglandin E, improved survival in C3/HEN mice challenged with 1 x 108 Escherichia coli organisms administered intraperitoneally. The administration of indomethacin decreased survival in the same model, and also increased mortality rates in C3/HEJ (endotoxinresistant) mice challenged with 1 x 108, 1 x 109 or 1 x 1010 Escherichia coli organisms. These results suggest that the elevation of PGE levels seen in burn patients may be a normal infection-related mortality and that attempts to decrease the rate of PGE synthesis in the bum patient through the use of cyclo-oxygenase inhibitors may in fact only increase the mortality rate in patients who develop infections. The elevated PGE levels would therefore not appear to be responsible for post-bum susceptibility to infectious complications.

Waymack J.P., Guzman R.F., Mason A.D. Jr, Pruitt B.A. Jr Bums, 16: 9:12, 1990.

DEEP PARTIAL SKIN THICKNESS BURNS: A REPRODUCIBLE ANIMAL MODEL TO STUDY BURN WOUND HEALING

The advent of new generations of drugs, topical agents and synthetic dressings imposes the need of a standard experimental model to evaluate their potential beneficial effects on the healing process of bum wounds. Such a bum model, using the guinea-pig, is described. Deep partial skin thickness bums were produced by round aluminium templates heated to 75 'C and applied for 5 s to the moistened, clipped and depilated dorsal skin. The three main components of burn wound healing can be studied by this method: epithelialization; contraction and scar formation. The report describes the method as followed with reference to over 1200 wounds over an 8-year period.

Kaufman T., Lusthaus S.N., Sagher U., Wexler M.R. Burns, 16: 13-16, 1980.

AN INVESTIGATION OF THE ANABOLIC ACTIVITY OF SOMATROPIN IN NORMAL AND BURNED RATS

This study was intended to investigate the effect of a standardized burn injury biosynthetic authentic human growth hormone (somatropin) in the rat, with particular reference to nitrogen balance and somatomedin response. A blind cross-over study was performed on 12 burned and 10 control rats, which received either somatropin or placebo for 5 days each in random order. Urinary nitrogen excretion increased significantly in the burned rats, and there was rapid weight loss. There were also significantly lower plasma somatomedin levels than in control rats. Only the control rats showed a significant increase in somatomedin levels after somatropin administration.Somatropin on the actions of administration failed to result in a significant improvement in nitrogen balance or weight gain in either control or burned rats. These results suggest that rats with normal pituitary function are not sensitive to the anabolic efl`ects of somatropin and that thermal injuries abolish the normal somatomedin reponse to somatropin.

Belcher RICK, Ellis H. Burns, 16: 17-20, 1990.

PROTEOGLYCAN-LYMPHOCYTE ASSOCIATION IN THE DEVELOPMENT OF HYPERTROPHIC SCARS

In hypertrophic scars after thermal injury there is a considerable increase in proteoglycans in comparison with those in normal scars and normal skin, and the presence of large amounts of chondroitin-4-sulphate may contribute to the overabundance of collagen deposition that is characteristic of this abnormal healing process. There is also a persistent presence of a perivascular cuff of variable density, mainly composed of mononuclear cells. In view of the importance of studying sections of hypertrophic scars, not only to identify the types of cell present but also to investigate their possible association with chondroitin-4-sulphate, it was decided to use monoclonal antibodies to achieve this aim, in an investigation in a total number of patients under the age of 16 years. Tissue sections were treated with monoclonal antibodies which specifically rec6gnize T-cells and unsulphated, 4-sulphated and 6-sulphated chondroitin proteoglycans. It was found that there was a striking association between the perivascular lymphocytic infiltration and chondroitin-4-sulphate. This may be an important contributory factor in the development of hypertrophic scars.

Linares H.A. Burns, 16: 21-24, 1990.

PULMONARY CAPILLARY DYNAMICS AND FLUID DISTRIBUTION AFTER BURN AND INHALATION INJURY

This study describes an extensive physiological and physiopathological model which may make possible the calculation or prediction of important variables in the analysis of the repercussions in pulmonary capillary dynamics of an inhalation injury combined with a thermal injury. The techniques used in the construction of the model are those of system's dynamics. The model was incorporated into a patient simulator and it is therefore possible to analyse the fluid and protein exchanges in a burn patient. Various regulating mechanisms are involved: pulmonary circulation, fluid and protein transfer between plasma and interstitial space at pulmonary capillary level, and the pulmonary lymphatic system. On the basis of the sensitivity analyses, it is proposed that for the simulation of the effects of inhalation injury at the pulmonary capillary level the parameters to be altered should be the pulmonary capillary permeability coefficient for proteins and the pulmonary capillary surface damaged by the thermal injury. In order to verify the utility and validity of the model the clinical progress of a series of bum patients with lung injuries was compared with results obtained using the patient simulator.

Roa L., Gornez-Cia T., Cantero A. Bums, 16: 25-35, 1990.

PAEDIATRIC BURN INJURIES IN THE JEDDAH AREA OF SAUDI ARABIA: A STUDY OF 197 PATIENTS

The main object of this research was to provide information on the pattern of paediatric burn injuries in the area of Jeddah, since such information had not previously been reported. A prospective study was carried out over a 2-year period (1985-87) on all patients admitted to the Bums Unit and this paper considers the 197 among them (61.75%) who were children up to the age of 18. Of these young patients 117 (59.4%) were infants and toddlers, 52 (26.4%) were pre-school and early school children, and 28 (14.2%) teenagers. Scalding and flame injuries were responsible for 98% of the bums, most injuries occurring at home (97.5%). The overall paediatric mortality rate was 4.4%. The importance is stressed of campaigns to reduce the number of such bums.

Jarnal Y.S., Ardawi M.S.M., Asky A.R.A., Shaik S.A. Bums, 16: 34-40, 1990.

PAEDIATRIC BURN INJURIES IN NEW ENGLAND, USA

The objective of this study was to extend the findings of previous analyses of data from the New England Regional Bum Program to describe the epidemiology of burn injuries for young people (up to the age of 19 years) in the six New England states. The period considered was 12 months (1978-79). It was found that of all patients hospitalized in the period, 41% (1128 out of 2742) were young people, corresponding to an overall bum incidence rate of 30.7 bums per 100,000 person-years. Children aged -2 years had a higher burn rate (96.7 bums per child-year) than children in any other age category. Males had a higher rate of burns than females in every age category. 63% of burns occurred in a residential setting. The commonest burn circumstance was food preparation and food consumption. This accounted for 42% of all burn injuries. It is concluded that the control strategies available to prevent the majority of burn injuries occurring to children should be complemented by effective educational interventions which encourage safe behaviour.

Rossignol A.M., Locke J.A., Burke J.F. Burns, 16: 41-48, 1990.

FATAL TAPWATER SCALDS IN THE USA, 1979-86

Between 1979 and 1986, 459 cases of fatal apwater scalds were reported to the Injury Information Clearing-house of the Consumer Product Safety Commission. Data were obtained from the death certificate file maintained by this organization. More than half the tap-deaths occurred in persons over 75 years old, and one fifth in children under 5 years. The USA is a multiracial society, and it was found that blacks, in all age groups, had a three-fold greater incidence of risk than females. One out of every eight fatal injuries occurred in a public building or residential institution. It would seem that innovative programmes directed towards homes with elderly or black residents could be the next step in eradicating this "accident", which affects people of all ages.

Walker A.R. Bums, 16: 49-52, 1990.

FIBRINOLYSIS INHIBITION IN HUMAN BURN BLISTER FLUID

Human burn blister fluid contains a plasmin inhibitor that compromises vascular patency. In burn patients antagonism of this inhibitor by the nonsteroidal anti -inflammatory drug, ibuprofen, may restore vascular patency and improve the survival of marginally viable surrounding skin. An investigation was carried out to investigate the possibly useful clinical implications of this antagonism. It was found that the activity of ibuprofen appeared to be unrelated to the synthesis of prostaglandins because other nonsteroidal drugs that were tested (indomethacin, imidazole and tolmetin) had significantly less antagonistic activity. These results are interesting in view of the vascular occlusion that the pla~min inhibition contained in bum blister fluid may induce, a condition that in patients suffering from thermal injuries may lead to secondary dermal ischaemia and necrosis.

Rockwell W.B., Ehrlich H.P. J. Burn Care Rehabil., 11: 1-6, 1990.

HISTOLOGIC STUDY OF ARTIFICIAL SKIN USED IN THE TREATMENT OF FULL-THICKNESS INJURY

An artificial skin model was developed in an attempt to provide early wound coverage and to minimize the need for autograft dermis in patients with deep partial-thickness or full-thickness burns. This artificial skin is a bi-layer membrane composed of a dermal portion consisting of a porous lattice of fibres of (1) a cross-linked bovine collagen and glycosaminoglycan composite material and (2) an epidermal portion made of silicone rubber. The glycosaminoglycan used is a chondroitin-6-sulphate. The dermal composite plus the synthetic epidermal .layer together is termed Integra artifical skin. Ten medical institutions participated in a histological study using Integra, involving 336 biopsy specimens from 131 patients with extensive, but not septic, thermal wounds. Six sequential phases of repair were distinguished in the study. Despite some unusual histological features (eosinophillc infiltration, macrophage-derived giant cell formation in the wound area), these did not clinically correlate with a negative response to Integra artificial skin. Apart from rare exceptions, repair was good, with intact dermis and definitive closure of a complete epidermal layer with a minimum of scarring.

Stem R., McPherson M., Longaker M.T. J. Bum Care Rehabil., 11: 7-13, 1990.

REPLACEMENT OF FULL-THICKNESS BURNS ON MICE WITH ISOGENEIC SKIN EQUIVALENTS

Full- and partial-thickness bums were produced in the backs of mice. The untreated partial-thickness burns healed by outgrowth of epidermal cells from hair follicles and adjoining skin, while the full-thickness bums formed linear scars. When the full-thickness bums were replaced by skin equivalents containing isogeneic fibroblasts and epidermal cells, the grafts were fully vascularized and covered with a comified epidermis within 2 weeks. At 6 month post-burn the skin equivalents retained 34% of their original area, while the untreated burns had contracted to 5% of their original area. In the first 2 weeks post-bum the splenic index in animals receiving burns followed by surgical excision and grafting was significantly greater than in the animals that had burns not followed by excision. This difference was however no longer significant by day 21 post-burn.

Hull B.E., Cool D.R. J, Burn Care Rehabil., ll: 14-20, 1990.

IMMUNOLOGIC STUDY OF ARTIFICIAL SKIN USED IN THE TREATMENT OF THERMAL INJURIES

A multicentre clinical study was carried out to evaluate the validity of Integra artificial skin, which consists of a bovine collagen and chondroitin6-sulphate dermal matrix with a silicone rubber "epidermal" layer. The temporary silicone rubber epidermal membrane is removed and the dermal collagen matrix is incorporated by the host. Serial se-rum samples indicated that few if any humoral immunological problems were caused by Integra artificial skin. There was also no evidence that skin collagen antibodies affected the clinical course of the patient or the take of the artificial skin.

Michaeli D., McPherson M. J. Bum Care Rehabil., 11: 21-26, 1990.

A NEW SURGICAL PROCEDURE FOR AGED BURN VICTIMS: APPLICATIONS OF DERMOLIPECTOMY FOR BURN WOUND AND DONOR SITES

The treatment of elderly patients with bum injuries often has poor results, because of the risks of surgical invasion and the thinning of skin with aging, which causes the raw surfaces of both excised wounds and donor areas to heal less successfully. The only advantage elderly patients may have is their loose and movable skin which facilitates excision and wound suture procedures. A metod based on dermolipectomy was therefore devised for use on bum wounds and donor sites in elderly burn patients. The procedure was employed over a 4-year period (1985-89) in 18 patients (20 operations; 4 burn wound sites; 39 donor sites). The lateral trunk was the commonest donor site. Actual survival rates were better than predicted survival rates in patients with bums over 21% to 40 TI1SA. There was only one post-operative death.

Ikeda J., Sugamata A., Jimbo Y., Yukioka T., Makino K. J. Burn Care Rehabil., Il: 27-31, 1990.

BURNS EPIDEMIOLOGY AND PREVENTION

With the ultimate goal of identifying possible burn prevention campaigns, a widescale survey was carried out of admissions to bums centres throughout Europe. The data collected concerned the age, sex and occupation of the patients, the cause and the place of the bum. Overall it was found that 30% of the patients were paediatric and 10% geriatric, without significant difference of incidence between the sexes. 10-20% of injuries could be classified as work-related. The bums can be generally classified as due to carelessness, due to faulty equipment, and burns caused in fires. The purpose of an effective bum prevention campaign is to satisfy two demands: economic (bum treatment in both the acute and chronic phase is extremely expensive) and psychosocial (because of the considerable humanitarian problems involved).

Gilardino P., Peri A., Ronchi A., Donati L. Riv. It. Chir. Plastica, 22: 79-101, 1990.

ACUTE NORMOVOLAEMIC HAEMODILUTION IN TREATING BURN PATIENTS

After a description of the technique of acute normovolaernic haemodilution, an account is given of its application in 82 bum patients with more than had 20% BSA. The patients maintained stable cardiocirculatory conditions, there were neither infective or metabolic sequelae nor immediate or delayed transfusional reactions. The results suggest that the technique has both medical and economical advantages.

Piscopo B., Lazzaro P., Mannelli S. Riv. It. Chir, Plastica, 22: 79-101, 1990.




 

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