Annals of Burns and Fire Disasters - vol. IX - n. 4 - December 1996

INTERNATIONAL ABSTRACTS

ACUTE MASS BURNS CAUSED BY O-CHLOROBENZYLIDENE MALONONETRILE (CS) TEAR GAS

It is generally maintained by those who have recourse to it that the effects of tear gas, if properly used, are transient and mainly only irritative to the mucous membranes of the eyes and respiratory passages. However, it is suggested in this article that tear gas may have more serious toxic effects and also cause acute bums. A description is given of a series of cases of acute bum injury which resulted from the use of o-chlorobenzylidene malononitrile (CS) tear gas during a situation of unrest in a Hong Kong Refugees' Detention Centre. In all, 47 females and 49 males were affected (age range, <1 to 51 years). The bums were classified as minor (range of TBSA burned, 1 to 8%; mean, 3%), and fell into three categories: flame bums (44 cases), contact burns (39 cases), and chemical bums (13 cases). Most patients suffered superficial or partialthickness bums, but two were admitted to a Burns Centre because of deeper burns; one of these required debriding and skin grafting. It is necessary to reconsider the potential toxic effects of CS tear gas as a riot control agent and to decide whether its use can indeed be condoned at all.

MANAGEMENT OF CANDIDA SEPTICAEMIA IN A REGIONAL BURN UNIT

Sepsis secondary to candida infection is a major cause of morbidity and mortality. The Augusta Regional Medical Center Burn Unit (USA) recorded 29 cases of candida septicaemia over a period of 40 months. All the cases presented features known to predispose to fungal sepsis. They had all suffered large bums (14-98% TBSA), all but one had at least one central venous line, and twenty-four required ventilatory support. The candida species responsible were: albicans alone, 14 (3 deaths); albicans and tropicalis, I; albicans and rugosa, 1 (1 death); parapsilosis alone, 8 (3 deaths); parapsilosis and glabrata 1; tropicalis alone, 4 (1 death). Twenty-five patients received amphotericin B, seven of these also receiving flucanozole. Two patients received flucanozole only, and two received no antifungal therapy. All eight deaths were attributed to sepsis, and all these patients had multiple organ failure. It is recommended that early and aggressive therapy be adopted in the presence of candida septicaemia, and amphotericin B would seem to be the drug of choice.

EPIDEMIOLOGICAL SURVEY OF BURNS TREATED IN ANKARA, TURKEY AND DESIRABLE BURN-PREVENTION STRATEGIES

A retrospective survey is presented of 1109 patients admitted over a 14-year period (1979-1993) to the bum unit at Hacettepe University in Ankara, Turkey. Of the patients, 57.5% were children (aged less than 16 years). The male/female ratio was 2.6A in adults and 1.4A in children. The causes of the burns in children and adults are analysed. The origin of the patients, from different parts of Turkey and the Mediterranean region, is also considered. Approximately two-thirds of the patients required one or more surgical interventions. The most important early complications were sepsis (59.5%) and acute renal failure (13.3%). The overall mortality rate was 34.4%. The epidemiological analysis showed the importance of safety campaigns to reduce the frequency of scalding among children. The analysis of the origin of the patients also suggests that regional considerations should be taken into account when prevention programmes are being planned.

SUICIDE ATTEMPTED BY BURNING: A 10-YEAR STUDY OF SELF-IMMOLATION DEATHS

It was found in a retrospective study that over a period of 10 years (1984-1993) 31 out of the 699 patients admitted to the Verona Burns Centre (Italy) in that period, i.e. 4.4%, had attempted suicide by burning. No significant sex difference was found; the mean age was 38 years (range, 25 to 65 years); and the mean TBSA was 41% (range, 8 to 95%). Twelve patients (38.7%) died, seven within the first day post-bum. Six of the 31 patients had previously attempted suicide, and a large number had at some time undergone psychiatric treatment. Four patients were drug addicts. After discharge the surviving patients were referred to mental health centres for psychiatric support. These patients, more than others, require ongoing psychiatric treatment, which is important for the prevention of further attempts at self-immolation.

REFLEX SYMPATHY DYSTROPHY OF BOTH PATELLAE FOLLOWING BURNS

Reflex sympathetic dystrophy (RSD) is defined as "continuous pain in a portion of an extremity after trauma, which may include fracture, but does not involve a major nerve, and associated with sympathetic hyperactivity." RSD affecting the knee has been widely described, but this study reports for the first time a case of RSD in both patellae following bums sustained in either knee. A 58-year-old man presented who was unable to walk or stand owing to intractable knee pain. He had previously suffered full-skin-thickness burns in both legs caused by molten rubber. The report includes information on the patient's physical examination findings, laboratory results, a socioeconomic and psychological assessment, and a description of rehabilitation therapy. The most important factor in the effective treatment of RSD is early recognition of the disease. An increased awareness of this complex syndrome will lead to better understanding and treatment.

EARLY ASSESSMENT OF PEDIATRIC BURN WOUNDS BY LASER DOPPLER FLOWMETRY

The assessment of partial-thickness bum injury in children is always a difficult problem, which can however be facilitated by use of a Laser Doppler Flownieter with a temperature-controlled multichannel probe. It was found in paediatric patients that the average perfusion levels for wounds that healed spontaneously in less than 21 days was significantly higher than average profusion levels that required excision and grafting or had not healed by day 21 post-burn. The Laser Doppler Flowmetry technique showed high positive predictive values for "nonhealing" wounds on days 1, 2, and 3 post-burn. The results of the survey indicate that this technique is a useful tool for burn wound assessment in children.

HEMODYNAMIC EFFECTS OF DELAYED INITIATION OF ANTIOXIDANT THERAPY (BEGINNING TWO HOURS AFTER BURN) IN EXTENSIVE THIRD-DEGREE BURNS

Burn injuries are characterized by increased microvascular permeability, which requires a large volume of resuscitation fluid during the first 24 hours post-burn. It was found in previous research that the initial 24-hour resuscitation fluid volume requirements can be reduced in guinea pigs by the immediate administration post-bum of adjuvant high-dose vitamin C. This experimental research was conducted to study the haemodynamic effects when the initiation of high-dose vitamin C is delayed up to two hours post-bum. Twelve adult guinea pigs were used. After being subjected to subxiphoid immersion in 100 'C water for 6 seconds, suffering 70% BSA third-degree burns, the animals were divided into two groups. Beginning half an hour post-bum, one group received Ringer's lactate solu~ tion plus vitamin C and the other control group only Ringer's lactate solution. Burn wound oedema was significantly less in the vitarnin C group, which also maintained adequate, haemodynamic stability as determined with haematocrit and cardiac output values, while the control group did not. It was found that even when vitamin C administration is delayed for over half an hour post-burn, the hourly infusion rate of the resuscitation fluid can be reduced by 25% once it is initiated. Antioxidant therapy with adjuvant vitamin C administration may thus be applicable in the clinical setting when patients arrive at a bums centre even some hours post-bum.

COMPARISON OF HEMODYNAMIC CHANGES RESULT. ING FROM TOXIC SHOCK SYNDROME TOXIN-1-PRODUCING STAPHYLOCOCCUS AUREUS SEPSIS AND ENDOTOXIN-PRODUCING GRAM-NEGATIVE ROD SEPSIS IN PATIENTS WITH SEVERE BURNS

This study was designed to analyse haemodynamic and metabolic differences resulting from gram-posifive cocci producing toxic shock syndrome toxin-1 (TSST-1) and gram-negative rods producing endotoxin, before and after septic shock. Five patients with severe burns who manifested Staphylococcus aureus sepsis were treated over a 5-year period at Kyorin Hospital Traumatology and Critical Care Center Bum Unit (Japan). The haemodynamic and metabolic differences in these patients were matched with those of five other burn patients with matching bum index and age in whom endotoxin-producing gram-negative rod sepsis developed. The relative findings are presented. This is the first clinical report to assert that TSST- 1 -producing gram-positive sepsis may lead to more hypermetabolic and hyperdynamic differences than endotoxin-producing gram-negative rod septic shock. These responses possibly indicate a stronger stimulation of cytokine and nitrous oxide synthetic acivity by TSST-1 than by endotoxin.

BURN INJURY RESULTS IN DECREASED GASTRIC ACID PRODUCTION IN THE ACUTE SHOCK PERIOD

Increased acid production is part of the stress response generated after acute injury, and much attention has been paid to acid-neutralizing agents in the prevention of gastrointestinal complications. The purpose of this study was to measure gastric mucosal pH and blood acid-base status at various levels in a marine burn model, and to determine a correlation between systemic metabolic acidosis and gastric mucosal pH. A number of female mice, 124 in all, were subjected to full-thickness burns in 25% TBSA. The animals were anaesthetized with methoxyflurane and resuscitated with 1 ml normal saline solution immediately post-burn. The animals were sacrificed at intervals of up to 24 hours. Their stomachs were removed and opened, and the gastric mucosal pH measured by use of a surface pH probe. In other animals, mixed venous blood was obtained via direct inferior vena cava puncture, and blood gas analysis was performed at intervals of up to 24 hours post-burn. Contrary to expectation, it was found that gastric mucosal pH increased in burned mice compared with that in controls. In this model, shock was observed to begin as early as one hour post-burn, reaching a maximum 12 hours post-burn. In the light of the higher gastric PH in burned mice with concomitant profound shock, gastric acid production would seem to be impaired during this time, and this in turn suggests that acute postburn gastrointestinal ulcerations could be due primarily to ischaernia. It is thus reasonable to affirm that the prevention of organic ischaernia may have a key role in the prevention of acute gastric ulceration after burn lesions.

HISTOLOGIC COMPARISON OF CULTURED EPITHELIAL AUTOGRAFT AND MESHED EXPANDED SPLITTHICKNESS SKIN GRAFT

This study concerned the histological examination of wounds grafted with cultured epithelial autograft (CEA) with that of wounds grafted with split-thickness skin graft (STSG) that had been meshed 1.5:1 and expanded. It was found that the histological appearance of the CEA biopsies obtained up to 2100 days after application in burn patients differed from time-matched STSG. The CEA interface with the underlying bed remained flat for up to three years in 75% of patients. CEA epidermal rete ridges, if formed subsequently, were fewer, thinner, and shorter, whereas expanded split-thickness skin grafts had well defined rete ridges after one year. The CEA basal layer remained separated from its bed for up to 50 days after application, and late blister formation was occasionally observed for up to three years. The underlying bed was homogeneous for periods of up to two years. Some beds subsequently demonstrated differentiation with superficial, fine, filamentous collagen fibres and deeper, thick, collagen fibres. Fine elastin filaments were initially identified in the superficial bed after one year on certain specimens and in all cases after three years. The poor adherence and poor stability may be due to the delay in rete ridge formation.

Putland M., Snelling C.F.T., Macdonald I., Tron V.A.
J. Burn Care Rehabil., 16: 627-40, 1995.