Avaliação microbiológica de coberturas com sulfadiazina de prata a 1%, utilizadas em queimaduras Evaluación microbiológica de coberturas con sulfadiazina de plata al 1% Microbiological evaluation of 1% silver sulfadiazine dressings

Os objetivos foram avaliar a condição microbiológica e atividade antimicrobiana de coberturas com sulfadiazina de prata a 1%, utilizadas em queimaduras, preparadas e estocadas de 12 a 60 horas antes do uso. A avaliação microbiológica foi realizada por semeadura de três alíquotas preparadas em diferentes tempos no meio de cultura Letheen Bloth (Difco) e incubadas a 32-35°C, durante 20 dias. A atividade antimicrobiana foi avaliada pela difusão de uma alíquota da cobertura frente às cepas hospitalares com incubação em temperatura ambiente até 37°C, por 18-24 horas. As três alíquotas de tempos 12, 36 e 60 horas foram negativas. Quanto à atividade antimicrobiana, observou-se "halo" de inibição de 2,25mm para S. aureus, 2,65mm para P. aeruginosa e 2,95mm para E. coli. Coberturas com sulfadiazina de prata a 1% podem ser pré-preparadas e armazenadas com segurança e têm como vantagens redução do tempo dos profissionais na realização do curativo e, conseqüentemente, da exposição do paciente.<br>La finalidad fue evaluar la condición microbiológica y la actividad antimicrobiana de coberturas con sulfadiazina de plata al 1%, preparadas y almacenadas 12-60 horas antes del uso. La evaluación microbiológica fue realizada por la siembra de tres proporciones preparadas en diferentes tiempos en el medio de cultivo Letheen Broth (Difco) y incubada a 32-35°C, durante 20 días. La actividad antimicrobiana fue evaluada por la difusión de una proporción ante las cepas hospitalarias, inicialmente con incubación en temperatura ambiente y después en 370C por 18-24 horas. Todos los tres cultivos de 12, 36 y 60 horas fueron negativos. Cuanto a la actividad antimicrobiana, las zonas de inhibición fueron de 2,25mm para S.aureus, 2,65mm para P. aeriginosa y 2,95mm para E coli. Coberturas con sulfadiazina de plata al 1% pueden ser preparadas y almacenadas con seguridad, y tiene como beneficio la reducción del tiempo de los profesionales en la realización del curativo y del tiempo de exposición del paciente.<br>This study aimed at evaluating the microbial condition and antimicrobial activity of 1% silver sulfadiazine dressings used in burns, prepared in advance of the dressing change and stored for 12 to 60 hours before usage. The microbial condition was evaluated by means of three cultures prepared from the Letheen Broth (Difco) culture medium and incubated at 32-35ºC for 20 days. Antimicrobial activity was evaluated by means of the diffusion technique of one dressing culture in hospital strains, initially incubated at room temperature and then at 37°C, for 18-24 hours. All three cultures of 12, 36 and 60 hours proved negative. Concerning antimicrobial activity, the zones of inhibition were: 2.25mm for S. aureus; 2.65mm for P. aeruginosa and 2.95mm for E. coli. These dressings can be safely prepared by nurses and stored, reducing nurses' time spent for dressing change and, consequently, patients' exposure

The NA(v)1.7 blocker protoxin II reduces burn injury-induced spinal nociceptive processing

Controlling pain in burn-injured patients poses a major clinical challenge. Recent findings suggest that reducing the activity of the voltage-gated sodium channel Nav1.7 in primary sensory neurons could provide improved pain control in burn-injured patients. Here, we report that partial thickness scalding-type burn injury on the rat paw upregulates Nav1.7 expression in primary sensory neurons 3 h following injury. The injury also induces upregulation in phosphorylated cyclic adenosine monophosphate response element-binding protein (p-CREB), a marker for nociceptive activation in primary sensory neurons. The upregulation in p-CREB occurs mainly in Nav1.7-immunopositive neurons and exhibits a peak at 5 min and, following a decline at 30 min, a gradual increase from 1 h post-injury. The Nav1.7 blocker protoxin II (ProTxII) or morphine injected intraperitoneally 15 min before or after the injury significantly reduces burn injury-induced spinal upregulation in phosphorylated serine 10 in histone H3 and phosphorylated extracellular signal-regulated kinase 1/2, which are both markers for spinal nociceptive processing. Further, ProTxII significantly reduces the frequency of spontaneous excitatory post-synaptic currents in spinal dorsal horn neurons following burn injury. Together, these findings indicate that using Nav1.7 blockers should be considered to control pain in burn injury