Infección quirúrgica en cirugía maxilofacial / Cross Infection in maxillofacial surgery

Objetivos. Determinar la incidencia de infección del lecho quirúrgico en un Servicio de Cirugía Maxilofacial que atiende a una población de 818.959 habitantes y analizar los factores de riesgo implicados en la misma. Método. Estudio de cohorte prospectivo (septiembre 1999noviembre 2000). Se incluyeron a todos los pacientes intervenidos quirúrgicamente por patología maxilofacial en este Servicio excepto aquellos ingresados por cuadros de celulitis odontógena y los sometidos a extracciones dentarias. Población total de estudio = 382. Seguimiento hasta treinta días posteriores a la intervención o un año si se requirió osteosíntesis.Diagnóstico de infección según criterios CDC. Análisis estadístico. bivariante, (Chi cuadrado, t-Student y regresión logística simple) y análisis multivariante (regresión logística múltiple). Paquete estadístico SPSS 10.0.Resultados. La incidencia total de infección quirúrgica fue del 9,4 por ciento. En cirugía traumatológica fue del 1.8 por ciento, en no traumatológica del 15,5 por ciento. Dentro de esta última, en procesos benignos, la incidencia de infección fue del 2,9 por ciento y en procesos malignos 20,9 por ciento. En el análisis multivariable resultaron como factores predictores de infección el tiempo de intervención superior a dos horas (OR=7, IC95 por ciento: 3,01-16,25), el grado de contaminación de la herida (OR=7,20, IC95 por ciento:1,25-26,52) y la reintervención quirúrgica (OR=6,29, IC95 por ciento:2,64-14,94). La incidencia de infección aumenta escalonadamente para cada unidad de incremento del índice NISS (Nacional Nosocomial Infection Surveillance) (OR=3,61, IC95 por ciento:2,38-5,60). Conclusiones. La incidencia de infección del sitio quirúrgico en cirugía traumatológica maxilofacial es baja, mientras que en cirugía no traumatológica es similar a la aportada por otros estudios. Los factores que de manera independiente se asocian a la infección son el tiempo de intervención, el grado de contaminación de la herida y la reintervención quirúrgica.La incidencia de infección aumenta a mayor puntuación del índice NISS. (AU)

Nonincreased risk of nosocomial infection during a 22-day housekeeping personnel strike in a tertiary hospital.

BACKGROUND: From April 2-23, 1992, the housekeeping staff of the University of Granada Hospital was on strike. Measures were implemented to minimize the effects of the strike on patients' health and especially to diminish the risk of hospital infection. OBJECTIVE: To assess the risk of nosocomial infection during the housekeeping personnel strike. SETTING: An 800-bed, tertiary care hospital. METHODS: A case-cohort approach was used. One hundred forty-eight infected patients (with 184 hospital infections) were detected prospectively from March 1, 1992, to May 31, 1992. A sample of 459 of the base population (patients admitted during the same period) was selected. Information on relevant risk factors for hospital infection was abstracted from patients' clinical charts after hospital discharge. Crude odds ratios and adjusted (by proportional hazards model) relative risks (RRs) for the strike period were estimated. RESULTS: Risk of nosocomial infection did not increase during the strike period (multiple-risk factor adjusted RR = 0.99, 0.96 to 1.01/day of strike). Similar results were observed for major sites of infection (especially surgical wound) and major areas of the hospital (including gynecology, surgery, and intensive care). CONCLUSION: We concluded that there was no increase in the risk of nosocomial infection during the housekeeping strike.

Validity of the cross-sectional study for the ascertainment of nosocomial infection risk factors.

This study was carried out in order to assess the validity of the pure cross-sectional study in the ascertainment of nosocomial infection risk-factors. The results yielded by two designs (cross-sectional and case-control) are compared. A cross-sectional design was performed in a tertiary hospital. 592 patients were studied, 38 of whom were nosocomially infected. The clinical information on all the patients included in this design was reviewed after hospital discharge. A matched case-control study was nested in the population cross-sectionally surveyed. 66 cases (28 additional patients developed a hospital infection) and 132 controls were selected. Odds ratios (ORs) for the risk factors analyzed by both designs were compared. There were no significant differences between the estimates yielded by both designs; however, a trend of lower OR estimates for the cross-sectional study was seen, which may be important for risk factors not strongly related to (low relative risk) nosocomial infection. Several factors which might account for the results observed (random error, bias introduced by matching) are discussed. It is suggested that pure cross-sectional designs for the study of risk factors of nosocomial infection may introduce a negative (toward-the-null) bias.