[Permanent pacing of the bundle of His after radiofrequency atrioventricular node ablation in patients with suprahisian conduction disturbances]

INTRODUCTION AND OBJECTIVES

The asynchronic contraction of the left ventricle due to left bundle branch block or right ventricular pacing is inferior from a hemodynamic point of view to the synchronic contraction through the conduction system. Several authors have reported some cases of pump failure and deterioration of mitral regurgitation after AV nodal ablation. Alternative sites of pacing such as the right ventricular outflow tract pacing have been proposed in order to avoid these complications. Direct His bundle pacing might be a new alternative for permanent pacing, however, it has not been extensively evaluated in humans yet. Our aim is to prove the feasibility of permanent His pacing in terms of stability, thresholds and pump function.

PATIENTS AND METHOD

POPULATION

patients without structural heart disease, selected for AV nodal ablation due to uncontrolled paroxysmal atrial fibrillation, or for pacemaker implantation due to supraHis conduction disturbance, with normal conduction system. An active fixation permanent lead was placed in His position using an steering guidewire and a diagnostic catheter as an anatomical reference. We also implanted a lead in the right atrial appendage and both were connected to a DDDR generator. Pacing thresholds and ecocardiographic ventricular function parameters were evaluated (ejection fraction, cavity size, mitral regurgitation).

RESULTS

12 patients met the inclusion criteria. Successful His pacing was achieved in 8 out of 12 cases (66%) with acceptable thresholds at implantation (1.24 +/- 0.13 volts at 0.5 ms) and during follow up at 3 months (1.31 +/- 0.20 volts at 0.5 ms). Neither a significant change in the ecocardiographic parameters not a deterioration in the clinical status caused by ablation or stimulation was evidenced.

CONCLUSION

The His bundle may be the site of choice for long term pacing in patients with AV block and normal infraHis conduction system.

Management of antimicrobial use in the intensive care unit

Indications for the use of antimicrobials in critically ill patients are similar to those for other hospitalised patients. However, the selection of agents depends on the particular characteristics of patients in the intensive care unit (ICU), the form of presentation of infection, the type of infection and the bacteriological features of the causative pathogens. The use of antimicrobials in patients admitted to medical-surgical ICUs varies between 33 and 53%. The selection of empirical antimicrobials to be included in treatment protocols of the most common infections depends on the strong interrelationship between patient characteristics, predominant pathogens in each focus. and antimicrobials used for treatment. Epidemiological studies carried out in the past have identified the microorganisms most frequently responsible for community-acquired and nosocomial infections in patients admitted to ICUs. Susceptibility to antimicrobial agents may be different between each geographical area, between each hospital and even within the same hospital service. In addition, susceptibility patterns may change temporarily in relation to the use of particular antimicrobials or in association with other unknown factors so that assessment of endemic antimicrobial resistance patterns is very useful in order to tailor the antimicrobial regimens of therapeutic protocols. Antimicrobial use should not be a routine procedure. The clinical course of the patient (an indicator of effectiveness) should be closely monitored as well as the possible appearance of adverse effects and/or multiresistant pathogens. Controls are based on the assessment of plasma drug concentrations and microbiological surveillance to detect the presence of multiresistant strains or new antibacterial-resistant pathogens. Prevention of the development of multiresistant pathogens is the main goal of the ICU antimicrobial policy. Although a series of general strategies to reduce the presence of multiresistant pathogens have been proposed, the implementation of these recommendations in ICUs requires the cooperation of a member of the intensive care team.

[Mortality and quality of life of patients beyond 65 years one year after ICU discharge]

BACKGROUND

Intensive care in elderly patients is a subject of controversy, because they generally present a high rate of mortality and short expectation of life. Due to the increasing life expectancy, more elderly patients will be treated in Intensive Care Unit (ICU) with an increasing consume of resources. The present study considers the mortality and quality of life (QOL) of patients beyond 65 years after ICU, and theirs predictors.

PATIENTS AND METHOD

Retrospective study of patients >= 65 years admitted in multidisciplinaire ICU. Mortality and QOL (with modified EuroQOL Instrument) one year after discharge were studied. To determine mortality and QOL one year independent predicting factors, multiple logistic regression models were used.

RESULTS

Of 313 patients studied, 95 (30%) died in ICU, 32 (10%) in hospital and 34 (11%) died after discharge. The independent predicting factors of mortality one year after ICU discharge were: organ failure (p < 0.000; odds ratio [OR], 2.9), cardiac surgery (p < 0.0000; OR, 0.15) and respiratory disease (p < 0.01; OR, 2.8). Of the 152 surviving patients, 21% got worse their previous QOL and only 17% were severely discapitated. The independent predicting factors of QOL one year after ICU discharge were: prior QOL (p < 0.0002; OR, 10.2) and age (p < 0.002; OR, 0.09).

CONCLUSION

Despite the high one year after ICU discharge mortality rate (51%), 83% of the survivors were able to live independently. Due to dependence between mortality and multiorganic failure during ICU stay and not age, this latter cannot be the determining factor of the care level.

Validación de la Escala de Ansiedad Preoperatoria y de Información Ámsterdam (APAIS) en mujeres latinoamericanas con cáncer de mama: Estudio México - Costa Rica

El tratamiento más frecuente contra el cáncer es la cirugía; sin embargo es un procedimiento invasivo que se ha asociado con la presencia de sintomatología psicológica hasta en el 76% de los pacientes. El estudio de la ansiedad ante la cirugía requiere de herramientas específicas adaptadas a las peculiaridades del constructo; entre ellas se encuentra la Escala de Ansiedad Preoperatoria y de Información Ámsterdam (APAIS) que ha sido validada en pacientes sometidos a diversas cirugías en múltiples países; mostrando consistentemente propiedades psicométricas adecuadas. Objetivo: Obtener la confiabilidad y validez de la APAIS en población oncológica para población latinoamericana. Método: Estudio transversal, no experimental, de análisis psicométrico que incluyó una muestra no probabilística de 117 mujeres con edades entre 25 y 75 años, todas diagnosticadas con cáncer de mama y programadas para cirugía en un hospital público de México (57 mujeres) o Costa Rica (63 mujeres). Resultados: Los seis reactivos de la Escala APAIS mostraron adecuada distribución de las contestaciones de las participantes entre las opciones de respuestas, tener capacidad de discriminación entre grupos extremos y contribuyeron a la consistencia interna del instrumento. El análisis factorial de máxima verosimilitud con rotación varimax mostró una estructura que explicó el 58,58% de la varianza con dos factores, la cual fue confirmada por análisis factorial confirmatorio; la escala total mostró una consistencia interna de α=0,816. Dicha escala mostró adecuada sensibilidad y especificidad con un punto de corte de 14 puntos. Conclusiones: La escala APAIS muestra propiedades psicométricas adecuadas para considerarla válida y confiable para evaluar ansiedad prequirúrgica en mujeres con cáncer de mama.