RESUMO
Treatment of supraventricular arrhythmia includes a wide range of medical interventions. Herbal remedies are suitable alternatives to synthetic drugs due to their availability, minimal side effects and lower price. Pharmacological studies and traditional medical literature point to the cardiovascular effects of Citrus aurantium L. (Rutaceae) in many instances. In the present study we used isolated perfused AV-node of rabbit as an experimental model to determine the effect of various concentrations of essential oil of C. aurantium (0.1-0.3 v/v) on the nodal conduction time and refractoriness of an isolated rabbit AV-nodal preparations. Selective stimulation protocols were used to independently quantify AV nodal recovery, facilitation and fatigue in 18 rabbits. Our results showed concentration-dependent and rate-independent suppressive effects of essence of C. aurantium on the Wenchebach cycle length (WBCL), AV Conduction Time (AVCT) and effective and functional refractory periods (ERP & FRP). Functional properties such as facilitation and fatigue were significantly increased by this plant. Citrus aurantium plays a protective role against the toxic effects of ouabaine by increasing AV nodal conduction time and refractoriness. The above results indicated differential effects of C. aurantium on slow and fast pathways, with a dominant role on fast pathways. This research has explained the protective role of C. aurantium on ouabaine toxicity. All results indicated the potential anti-arrhythmic effects of C. aurantium in treating supraventricular tachyarrhythmia.
El tratamiento de la arritmia supraventricular incluye una amplia gama de intervenciones médicas. Los remedios herbarios son alternativas adecuadas a las drogas sintéticas debido a su disponibilidad, con escasos efectos secundarios y bajo precio. Estudios farmacológicos y la literatura médica tradicional señalan los efectos cardiovasculares de Citrus aurantium L. (Rutaceae) en muchos casos. En el presente estudio se usaron aislados perfundidos del nodo AV de conejo como modelo experimental para determinar el efecto de diferentes concentraciones de aceite esencial de C. aurantium (0,1-0,3 v/v) sobre en el tiempo de conducción nodal y refractariedad. Un protocolo de estimulación selectiva se utilizó para cuantificar de forma independiente la recuperación, la facilitación y la fatiga del nodo AV en 18 conejos. Nuestros resultados muestran efectos supresores dependientes de la concentración e independiente de la velocidad de la esencia de C. aurantium sobre la duración del ciclo Wenchebach (WBCL), tiempo de conducción AV (AVTC) y períodos refractarios eficaz y funcional (PRE y PRF). Propiedades funcionales tales como la facilitación y la fatiga se incrementaron de manera significativa por esta planta. La Citrus aurantium juega un papel protector contra los efectos tóxicos de ouabaína al incrementar el tiempo de conducción AV nodal y la refractariedad. Los resultados indican efectos diferenciales de C. aurantium sobre las vías lentas y rápidas, con un papel dominante en las vías rápidas. Esta investigación ha explicado el papel protector de C. aurantium sobre la toxicidad ouabaine. Todos los resultados indican los posibles efectos anti-arrítmicos de C. aurantium en el tratamiento de taquiarritmias supraventriculares.
Assuntos
Animais , Coelhos , Óleos Voláteis/farmacologia , Citrus/química , Nó Atrioventricular , Ouabaína/antagonistas & inibidores , Arritmias Cardíacas/tratamento farmacológico , Eletrofisiologia Cardíaca , Ouabaína/toxicidade , Preparações de Plantas/farmacologia , Fatores de TempoRESUMO
OBJECTIVE: Nosocomial infections are one of the most important causes of mortality and morbidity in hospitals. These are major public health problems worldwide, but particularly in developing countries. These infections have the most common frequency in pediatric hospitals-especially in neonatal wards- second to burn hospitals. In the present study, neonatal nosocomial infections have been reviewed in Bahrami Children Hospital from fall of 1999 through fall of 2004. METHODS: Nosocomial infected patients were defined as all patients who were neither infected not were in incubation period at the admission time and had positive culture after third day of admission. The incidence of nosocomial infections computed as infections per 100 hospital discharges and infections per 100 hospital days. Chi square test was used for comparison of rates. RESULTS: Fifty-two patients had been diagnosed having nosocomial infections. NICU (Neonatal Intensive Care Unit) showed the highest portion of infections (40%) followed by neonatal surgery ward (35%) and neonates ward (25%). Frequencies of nosocomial infection by site were as follows: eyes (27%), septicemia, surgical wounds and location of drain or catheter (each one 21%), CSF (7%) and urinary (2%). The most common pathogenic organisms were Enterobacter (27%), aurues Staphilococcus (21%), Klebsiella (18%), E.coli (14%) and epidermis Staphilococcus (9%). Total number of hospitalized patients was 5990 and total number of hospitalized days was 39,095 in the five years. Infections per 100 hospital discharges and 100 hospital days by service were as follows, respectively: NICU (2.9, 0.26), neonatal surgery (1.7, 0.18) and neonates (0.3, 0.06). The differences were significantly meaningful (p value< 0.001). CONCLUSION: These findings provide useful information for future surveillance in association with prevention programs. Subsequently, surveillance should be focused on high-risk patients in intensive care unit and/or who have undergone surgery and invasive procedures.