Burns, endothelial dysfunction, and oxidative stress: the role of antioxidants.

Background. Burns cause a systemic inflammatory response, endothelial dysfunction, and increased microvascular permeability which results in oedema being formed; these effects are probably the result of a complex interplay between the direct effects of heat on the microcirculation and the action of chemical mediators, including reactive oxygen species. The use of antioxidants can reduce these changes, which are considered a promised step in burns management. Patients and methods. Forty-eight burn patients of either sex and with varying burns percentages were involved in the study. They were each allocated to one of four groups: A, B, C, and D, each group composed of 12 patients. Groups B, C, and D were treated with antioxidants: allopurinol, melatonin, and N-acetylcysteine respectively, while group A was treated according to normal hospital policy, without antioxidants; 12 healthy subjects (group E) served as a control group for comparison. In each group, serum malondialdehyde and serum glutathione levels were measured and liver and kidney function tests were performed, as well as microalbuminuria tests, using standard methods. Results. The administration of antioxidants to burns patients produced significant improvements in the parameters studied compared to group A parameters (no antioxidant given). Conclusion. This study clearly demonstrates the role of reactive oxygen species in endothelial dysfunction occurring in burn patients and the beneficial effect of antioxidants in reducing it, as shown by the reduced microalbuminuria and reduced resuscitation fluid in antioxidant-treated burn patients; the study also supports newly emerging evidence regarding the use of microalbuminuria as an indicator for endothelial dysfunction in burn patients.

Role of antioxidants in the treatment of burn lesions.

Burns are a major health problem worldwide, with high mortality and morbidity in addition to causing changes in the quality of life of burn patients. Utilizing antioxidant therapeutic strategies depending on new mechanisms involved in the pathogenesis of burns-related "oxidative stress" may be considered a promising step in burns management. This study involved 180 burn patients of varying age and either sex and with varying burns percentages. The patients were subdivided into six groups (A, B, C, D, E, and F); each group thus included 30 patients. Patients in groups B, C, D, E, and F were treated with antioxidants (vitamin E with vitamin C, zinc sulphate, allopurinol, melatonin, and N-acetylcysteine respectively) while group A was treated according to hospital policy, without any antioxidant; also, healthy subjects (group G) were involved in the study as a control group for comparison.In each group we examined serum malondialdehyde and serum glutathione levels, serum zinc and copper levels, liver function, renal function, mortality rate, and healing time, using standard methods. It was found that the administration of antioxidants to burn patients produced significant improvement in the parameters studied compared with group A (no antioxidant given). This study clearly shows the importance of the therapeutic targeting of oxidative stress in the treatment of burns. It is important to consider antioxidant a most effective weapon that must be added to the arsenal available in the combating of burn complications.

How to decrease the incidence of eschar formation during the use of topical povidone-iodine ointment in the treatment of burns.

The aim of this study was to prevent eschar formation in thermally injured patients during the use of povidoneiodine ointment by modifying therapeutic protocols depending on normal events in healing process. Sixty thermally injured patients of different age groups, sex, and occupation with different burn sizes were involved in the study, allocated to two groups. Group A was made up of 17 patients treated with topical povidone-iodine ointment in addition to other prescribed drugs according to the burn unit regimen, while group B was comprised of 43 patients treated with topical povidone-iodine ointment for the first four days post-injury followed by topical silver sulphadiazine cream until discharge and with other prescribed drugs according to the burn unit regimen. In both groups the following were studied, using standard methods: oxidative stress parameters; thyroid, liver, and renal function test; microbiology; mortality rate; healing time and economic aspects. It was found that treatment of burn patients with topical povidone-iodine ointment for the first four days post-injury followed by topical silver sulphadiazine cream reduced the incidence of eschar formation from 100% to 2.3%, in addition to maintaining improvement in burn outcome when using povidone-iodine ointment during the full course of treatment. It is concluded that for the modification of treatment protocols in burns designed to obtain normal wound healing and at the same time to avoid the undesirable effects of the treatment given, the use of topical povidone-iodine ointment for the first four days post-injury, followed by topical silver sulphadiazine cream, was a good application. In addition, this study clearly shows the importance of the therapeutic targeting of oxidative stress in burn treatment, especially during the first four days post-injury, a period when blood levels of oxidative stress parameters are at a maximum.

Effect of zinc supplement in the prognosis of burn patients in iraq.

Many studies have reported that zinc plasma levels significantly decrease after a burn, leading to zinc deficiency, and that increased free radical generation and decreased natural antioxidant may negatively affect wound healing and burn outcome in general. Targeting of these changes is considered an important strategy in the treatment of burns in an attempt to improve burn outcome in the clinical setting. Zinc was given orally in a nutritional dose (15 mg elemental zinc) as a zinc sulphate capsule to burn patients in order to improve post-burn zinc deficiency and burn outcome. The study was carried out in 58 burn patients of different age groups, sex, and occupation with different burn size. The patients were allocated to two groups: group A patients (43 in number) were treated with topical povidone-iodine ointment for the first four days post-injury followed by topical silver sulphadiazine cream 1% until discharge in addition to other prescribed drugs according to our burn unit policy; group B patients (15) received the same treatment as group A plus a single daily oral dose of zinc sulphate in a 66 mg capsule, equivalent to 15 mg elemental zinc. In each group, using standard methods, we considered plasma zinc and copper levels, oxidative stress parameters, thyroid, liver, and renal function tests, microbiological factors, mortality rate, healing time, and cost effectiveness. The administration of zinc in dietary doses significantly increased the plasma zinc level in burn patients to around normal control levels and improved the antioxidant status, as represented by elevation of the natural antioxidant level (glutathione), in addition to improving healing time, the incidence of eschar formation, and the mortality rate, compared with the zinc-nonsupplemented group. We conclude that dietary zinc supplementation in zinc-deficient burn patients led to great improvements in their outcome and that zinc deficiency was as an important goal to target during treatment; also, that the use of a combination of topical and systemic antioxidants (povidoneiodine ointment and zinc sulphate, respectively) represented a good strategy for improving results in burn patient treatment.

Role of the antioxidant effect of vitamin e with vitamin C and topical povidone-iodine ointment in the treatment of burns.

Objective. Burns represent a major health problem worldwide, with high mortality and morbidity and economic loss even with small burns. Changes in medical treatment protocols depending on a new mechanism involved in the pathogenicity of burns, i.e. oxidative stress (such as the use of povidone-iodine alone or in combination with vitamin E and vitamin C) may improve the outcome and reduce the economic loss. Patients and methods. Thirty-eight thermally injured patients of different age groups, sex, and occupation with different burn size, admitted to the burn unit in Baquba General Hospital, Iraq, were involved in this clinical trial. The patients were allocated to three groups: group A (8 patients), treated according to hospital policy; group B (17 patients), treated with topical povidone-iodine ointment; and group C (13 patients), treated with topical povidone-iodine ointment with systemic once daily 400 mg vitamin E and 500 mg vitamin C in addition to the classical antibiotic used by our hospital. In each group of oxidative stress parameters, the thyroid, liver, and kidney function test, microbiological studies, the mortality rate and healing time measurements, and economic studies were performed using standard methods. Results. Treatment with topical povidone-iodine ointment or in combination with systemic vitamin E and vitamin C was found to be of significant benefit in improving oxidative stress parameters, the mortality rate, healing time, and cost, and was free of any adverse thyroid, hepatic, or renal effects. Conclusion. Treatment of thermally injured patients with topical povidone-iodine ointment significantly improved oxidative stress parameters, indicating its antioxidant effect. Further investigation is needed to explain the exact mechanism by which povidone-iodine exerts this antioxidant effect. Treatment with topical povidone-iodine ointment alone or in combination with systemic vitamin E and vitamin C significantly improves the outcome of thermally injured patients in a safe way, thanks to the newly emerged mechanism - oxidative stress - involved in burns pathogenesis.

Respiratory effects of low-dose bupivacaine interscalene block.

In this double-blind study, interscalene brachial plexus (ISBP) block was performed in 11 volunteers using 10 ml of either 0.25% (n = 6) or 0.5% (n = 5) bupivacaine with epinephrine 1:200,000. Diaphragmatic excursion, respiratory function and neural function were assessed for 90 min. Our results showed that hemidiaphragmatic excursion declined significantly after block in the 0.5% group and paradoxical movement during inspiration was more common than in the 0.25% group. Forced vital capacity and forced expiratory volume in 1 s declined significantly in the 0.5% group (mean 74.6 (SD 13.0)% and 78.2 (19.9)% of baseline, respectively) but not in the 0.25% group. Sensory anaesthesia in the upper limb was found consistently in both groups, although biceps paralysis occurred earlier after 0.5% bupivacaine. We conclude that ISBP block using 10 ml of 0.25% bupivacaine provided upper limb anaesthesia to pinprick in C5-6 dermatomes with only occasional interference with respiratory function.