Evaluating the Fluid Balance of Mechanically Ventilated Patients by Ultrasonography
Evaluating the Fluid Balance of Mechanically Ventilated Patients by Ultrasonography
ratio of the diameter of inferior vena cava to the diameter of the thoracic aorta (IVC / Ao)
 depends on the daily balance of fluids.
During the routine abdominal ultrasound, the basilar and abdominal aorta were measured using
 a Sparq Philips ultrasonograph with a convex probe set in abdominal mode. All measurements
 were performed in one patient by the same operator who were experienced and performed the
 appropriate course of ultrasonography. The IVC and abdominal aorta were visualized using a
 paramedian long-axis view via a subcostal approach according to the methodology described by
 the American Society of Echocardiography. Inferior vena cava width was assessed at an
 interval of approximately 1 cm distal from connection of the hepatic vein to the inferior
 vena cava. No significant changes were observed in the width of the inferior vena cava during
 various respiratory phases, because of the positive pressure ventilation. The widest value
 was always chosen for the data. The assessment of the width of the abdominal aorta was
 performed above arise of the celiac trunk, at the height of the vein of the lower vena cava.
 The width of the inferior vena cava and the abdominal aorta was assessed using transthoracic
 ultrasound for the following five days. Daily differences in the amount of fluid intake and
 lost was recorded. CVP measurement was performed.
Inclusion Criteria:

 -  patients who were hospitalized in the Intensive Care Unit

 -  severe respiratory failure requiring mechanical ventilation

 Exclusion Criteria:

 -  spontaneous breathing,

 -  severe vascular disease,

 -  increased intra-abdominal pressure,

 -  cardiac pacemaker

 -  cardioverter defibrillator