Vacuum-assisted wound closure system (VAC®) has consolidated as an important tool for the management of post-sternotomy mediastinitis in neonates. Its use has reduced significantly the associated morbimortality in these cases. However, there are no controlled studies that could help to establish a treatment protocol. We report our experience with 2 cases in neonates where the VAC® system was used successfully to managed post-sternotomy mediastinitis between June 2009 and February 2010, and we make a literature review of the published data about the subject. With the obtained data we propose treatment guidelines in the management of this dreaded complication of cardiac surgery.

El sistema VAC® ha conseguido, en los últimos años, consolidarse como un pilar esencial en el manejo de la dehiscencia de esternotomía media infectada en pacientes neonatos. Su aplicación, tanto de forma aislada como combinada con otros tratamientos, ha logrado disminuir de manera importante la morbimortalidad asociada a esta entidad. Sin embargo, todavía no existen estudios controlados que ayuden a establecer un protocolo de tratamiento. Presentamos 2 casos tratados entre junio del 2009 y febrero del 2010, así como una revisión bibliográfica sobre la aplicación del sistema VAC® en la dehiscencia de esternotomía media infectada en el paciente neonato. Con los datos obtenidos intentamos establecer una pauta de tratamiento que pueda ayudar a la resolución de esta temida complicación en cirugía cardíaca.

Background: A progressive frequency of resistance to fluorquinolones is observed among Gram-negative bacilli. Aim: To investigate the mechanism of resistance to fluoroquinolones mediated by mutations affecting gyrA and gyrB genes in strains of Gram negative bacüli isolated from CMean hospitals. Material and method: Minimal inhibitory concentration of fluoroquinolones was determined in 91 randomly selected nalidixic acid-resistant strains of Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii and Pseudomonas aeruginosa, isolated from hospitals of 12 Chilean cities. Quinolone resistance determining region (QRDR) was amplified by PCR and mutations were determined by restriction fragment length polymorphism (RFLP) and DNA sequencing. Results: Strains with mutation in codon 83 of gyrA showed decreased susceptibility to ciprofloxacin with MICs ranging from 0.25 to 1024 fig/ml. The sequencing of PCR products for gyrA indicated amino acid changes in the QRDR region. One strain ofE. coli presented a double mutation, in codon 83 Ser to Leu as well as in codon 87 Asp to Asn. In strains ofK. pneumoniae, however, the change of codon 83 was Ser to Tyr, in A. baumannii was Ser to Leu and in P. aeruginosa was Thr to He. No strains with mutations affecting gyrB were found. Conclusions: Mutations in codon 83 of gyrA is a frequent genetic event involved in the mechanism leading to decreased susceptibility to fluoroquinolone in strains of Gram-negative bacilli