Uso de diagramas de controle na vigilância epidemiológica das infecções hospitalares

OBJECTIVE: To monitor occurrence trends and identify clusters of nosocomial infection (NI) using statistical process control (SPC) charts. METHODS: Between January 1998 and December 2000 nosocomial infection occurrence was evaluated in a cohort of 460 patients admitted to the Pediatric Intensive Care Unit of a university hospital, according to the concepts and criteria proposed by the National Nosocomial Infection Surveillance System of the Centers for Disease Control, in the United States. Graphs were plotted using Poisson statistical distribution, including four horizontal lines: center line (CL), upper warning limit (UWL) and upper control limit (UCL). The CL was the arithmetic mean NI rate calculated for the studied period; UWL and UCL were drawn at 2 and 3 standard deviations above average NI rates, respectively. Clusters were identified when NI rates remained above UCL. RESULTS: Mean NI incidence was 20 per 1,000 patient days. One urinary tract infection cluster was identified in July 2000, with an infection rate of 63 per 1,000 patient days, exceeding UCL and characterizing a period of epidemic. CONCLUSIONS: The use of SPC charts for controlling endemic levels of NI, through both global and site-specific evaluation, allowed for the identification of uncommon variations in NI rates, such as outbreaks and epidemics, and for their distinction from the natural variations observed in NI occurrence rates, without the need for calculations and hypothesis testing.OBJETIVO: Monitorizar a tendência de ocorrência e identificar surtos de infecções hospitalares utilizando diagramas de controles. MÉTODOS: No período de janeiro de 1998 a dezembro de 2000, a ocorrência de infecções hospitalares foi avaliada em uma coorte de 460 pacientes, internados em uma Unidade de Terapia Intensiva Pediátrica de um hospital universitário, segundo os conceitos e critérios da metodologia do sistema "National Nosocomial Infection Surveillance", do "Centers for Disease Control" (EUA). Os gráficos foram construídos de acordo com a distribuição probabilística de Poisson. Quatro linhas horizontais foram plotadas. A linha central foi representada pela incidência média das infecções hospitalares no período estudado e as linhas de alerta superior e de controle superior foram calculadas a partir de dois e três desvios-padrão acima da incidência média das infecções hospitalares, respectivamente. Os surtos de infecção hospitalar foram identificados quando sua incidência mensal permaneceu acima da linha do limite de controle superior. RESULTADOS: A incidência média de infecções hospitalares por mil pacientes dia foi de 20. Um surto de infecção do trato urinário foi identificado em julho de 2000, cuja taxa de infecção foi de 63 por mil pacientes dia, ultrapassando a linha de controle superior, configurando um período epidêmico. CONCLUSÕES: A utilização dos diagramas de controle do nível endêmico, tanto por avaliação global e sítio específica, possibilitou identificar e distinguir das variações naturais nas taxas de ocorrência de infecções hospitalares aquelas de causas incomuns, como os surtos ou epidemias, dispensando o uso de cálculos e testes de hipóteses

Vacinação contra o sarampo: influência da idade em sua eficácia

The authors compare the serologic efficacy and the clinical protection afforded by three different measles vaccination schemes in adequately nourished children in São Paulo city, Brazil. Two hundred forty two children were divided into three groups. Group A, comprising 117 children who had received the vaccine before 12 months of age and a second dose at 12 months of age or more. Group B, comprising 46 children who had received only one dose, before 12 months of age. Group C, comprising 79 children who had received only one dose, at 12 months of age or more. The geometric mean titer of antibodies in Group A was 790.1; in Group B, 251.1; and in Group C, 550.3. There was no statistically significant difference between Groups A and C. The exposure to the measles virus was probably similar in all groups, and the children in Groups A and C had similar chances of acquiring the disease after vaccination whereas in Group B the chances were higher when compared to the other two groups. The results obtained in this study favor the use, in developing countries, of a vaccination program against measles that includes an early first dose at eight months of age and revaccination after 12 months of age.Os autores comparam a eficácia sorológica e a proteção clinica obtidas com três esquemas diferentes de vacinação contra o sarampo, em crianças eutróficas, na cidade de São Paulo, Brasil. Duzentas e quarenta e duas crianças foram divididas em três grupos. Grupo A, compreendendo 117 crianças primovacinadas antes dos 12 meses de idade e revacinadas com 12 ou mais meses de idade. Grupo B, compreendendo 46 crianças vacinadas com dose única, antes dos 12 meses de idade. Grupo C, compreendendo 79 crianças vacinadas com dose única, aos 12 ou mais meses de idade. A média geométrica do título de anticorpos no grupo A foi 790,1; no grupo B, 251,1; e no grupo C, 550,3. Não houve diferença estatisticamente significante entre os grupos A e C. A exposição ao vírus do sarampo foi provavelmente semelhante em todos os grupos. As crianças dos grupos A e C apresentaram risco de adoecimento semelhante após vacinação, enquanto que tal risco foi maior no grupo B quando comparado aos outros dois grupos. Os resultados obtidos neste estudo falam a favor do uso, em países em desenvolvimento, de um programa de vacinação contra o sarampo que inclua uma primeira dose àos oito meses de idade e revacinação após os 12 meses de idade

Impact of an intervention in the use of sequential antibiotic therapy in a Brazilian university hospital

INTRODUCTION: Sequential antibiotic therapy (SAT) is safe and economical. However, the unnecessary use of intravenous (IV) administration usually occurs. The objective of this work was to get to know the effectiveness of an intervention to implement the SAT in a teaching hospital in Brazil. METHODS: This was a prospective and interventional study, historically controlled, and was conducted in the Hospital de Clínicas, Universidade Federal de Uberlândia, State of Minas Gerais, Brazil, a high complexity teaching hospital having 503 beds. In each of the periods, from 04/04/05 to 07/20/05 (pre-intervention) and from 09/24/07 to 12/20/07 (intervention), 117 patients were evaluated. After the pre-intervention period, guidelines were developed which were implemented during the intervention period along with educational measures and a reminder system added to the patients' prescription. RESULTS: In the pre-intervention and intervention periods, the IV antibiotics were used as treatment for a average time of 14.8 and 11.8 days, respectively. Ceftriaxone was the antibiotic most prescribed in both periods (23.4% and 21.6% respectively). Starting from the first prescription of antibiotics, the average length of hospitalization time was 21.8 and 17.5 days, respectively. The SAT occurred only in 4 and 5 courses of treatment, respectively, and 12.8% and 18.8% of the patients died in the respective periods. CONCLUSIONS: Under the presented conditions, the evaluated intervention strategy is ineffective in promoting the exchange of the antibiotic administration from IV to oral treatment (SAT)