La ecografía es a día de hoy una herramienta muy importante para el médico intensivista, cuyo uso se va difundiendo cada vez más. Sin embargo, no basta con adquirir las habilidades técnicas para su realización, sino que también, y quizá más importante, hay que saber interpretar los hallazgos que encontremos, para lo cual un adecuado conocimiento de la fisiología o fisiopatología subyacente es fundamental. Tal es el caso de la comprensión de los mecanismos o fuerzas involucradas en la distensión y colapso de la vena cava inferior con el fin de darle una adecuada aplicación clínica a las imágenes que se obtienen cuando se analiza esta variable.

In recent years, both in different studies and in usual clinical practice, it has been demonstrated the utility of bedside ultrasound to optimize the management of critically ill patients. Today it should be an additional tool to guide us in the management of these patients. This article presents the utility of bedside ultrasound in the disease detection and management of a female patient with early signs of cardiac tamponade before the development of severe hypotension. Such ultrasound allowed making an early decision for her treatment, which subsequently affected her recovery.

Nowadays ultrasonography is a very important tool for intensive care physicians, the use of which is spreading more and more. However, it is not enough to acquire the technical skills to perform it, but also -and perhaps more importantly- we must know how to interpret the findings, for which an adequate knowledge of physiology or underlying pathophysiology is critical. Such is the case of understanding the mechanisms or forces involved in the distension and collapse of the inferior vena cava, in order to provide an adequate clinical application to the images we get when we analyze this variable.

Plastic bronchitis is a rare but potentially fatal disease because of obstruction of the airway, which can occur at any age. Due to its infrequency, it doesn´t have a well-defined treatment and that we can found is based on anecdotal experiences. In the presence of increased pressure on the mechanical ventilator with a marked difference between the peak pressure and plateau pressure, we should suspect of endotracheal tube obstruction and if necessary, we must change it, especially if the patient begins to desaturate and become unstable.