Is a strategy based on routine endotracheal cultures the best way to prescribe antibiotics in ventilator-associated pneumonia?

OBJECTIVES: The objectives of this study were to evaluate if a strategy based on routine endotracheal aspirate (ETA) cultures is better than using the American Thoracic Society/Infectious Diseases Society of America (ATS/IDSA) guidelines to prescribe antimicrobials in ventilator-associated pneumonia (VAP). METHODS: This was a prospective, observational, cohort study conducted in a 15-bed ICU and comprising 283 patients who were mechanically ventilated for ≥48 h. Interventions included twice-weekly ETA; BAL culture was done if VAP was suspected. BAL (collected at the time of VAP) plus ETA cultures (collected≤7 days before VAP) (n=146 different pairs) were defined. We compared two models of 10 days of empirical antimicrobials (ETA-based vs ATS/IDSA guidelines-based strategies), analyzing their impact on appropriateness of therapy and total antimicrobial-days, using the BAL result as the standard for comparison. RESULTS: Complete ETA and BAL culture concordance (identical pathogens or negative result) occurred in 52 pairs; discordance (false positive or false negative) in 67, and partial concordance in two. ETA predicted the etiology in 62.4% of all pairs, in 74.0% of pairs if ETA was performed≤2 days before BAL, and in 46.2% of pairs if ETA was performed 3 to 7 days before BAL (P=.016). Strategies based on the ATS/IDSA guidelines and on ETA results led to appropriate therapy in 97.9% and 77.4% of pairs, respectively (P<.001). The numbers of antimicrobial-days were 1,942 and 1,557 for therapies based on ATS/IDSA guidelines and ETA results, respectively (P<.001). CONCLUSIONS: The ATS/IDSA guidelines-based approach was more accurate than the ETA-based strategy for prescribing appropriate, initial, empirical antibiotics in VAP, unless a sample was available≤2 days of the onset of VAP. The ETA-based strategy led to fewer days on prescribed antimicrobials.

Interrelationship between oxygen-related variables in patients with acute myocardial infarction: an interpretative review.

The high mortality rate of cardiogenic shock in acute myocardial infarction (AMI) implies that debate over the correct haemodynamic management is still unresolved. The purpose of this review is to re-evaluate the reciprocal relationships between oxygen-related variables and response to treatment in a large number of patients with AMI. A MEDLINE search of reports published between 1970 and 2008 was performed. Twelve clinical reports including 453 patients with AMI and 989 sets of oxygen delivery and oxygen consumption expressed in ml min⁻¹ m⁻² and oxygen extraction ratio were selected. While processing this data, we found an early down-regulation in oxygen demand linked to a decrease in oxygen supply. This mechanism is also supported in some studies by a critically low oxygen uptake that was not associated with lactic acidosis.

[Acute respiratory distress syndrome. Role of steroids]. / Síndrome de distrés respiratorio agudo. Utilidad de los corticoides.

The acute respiratory distress syndrome (ARDS) represents 7.7% of the intensive care population, and is associated with great morbidity and mortality (58%). Frequently, the mortality can be attributed to more than one cause. Refractory hypoxemia is uncommon (15%) and most of the patients also have multiple organic dysfunction, sepsis or septic shock. Although there are many publications concerning series of cases and clinical trials using steroids as a part of the treatment of ARDS, this issue remains controversial. In this article the role of steroids in the ARDS is evaluated by analysis of the available literature. We conclude that steroids are useful in a subgroup of patients with unresolving ARDS, after ruling out an active infection or after treatment with antibiotics.

Sindrome de distres respiratorio agudo utilidad de los costicoides / Acute respiratory distress syndrome: role of steroids

En Argentina, el síndrome de distrés respiratorio agudo (SDRA) representa el 7.7% de las admisiones en terapia intensiva y está asociado con una alta morbilidad y mortalidad (58%). Con frecuencia la muerte puede ser atribuida a más de una causa. La hipoxemia refractaria es una causa de muerte poco frecuente (15%) y en muchos casos puede coexistir con disfunción multiorgánica, sepsis o shock séptico. La utilidad de los esteroides como parte del tratamiento es aún motivo de debate a pesar de las múltiples series de casos y estudios clínicos publicados. En el artículo se evalúa la utilidad de los esteroides en el SDRA a través de la revisión de la bibliografía disponible. Se concluye que los esteroides estarían indicados en un pequeño subgrupo de pacientes con SDRA no resuelto o tardío, después de descartar o controlar una infección activa.