Figure 2 shows the distribution (%) of the cases (15 on the whole) of aggravated renal dysfunction among the 3 IVCCI layers during intensive loop diuretic treatment.
As represented in Figure 4, in IVCCI=16-40% range, eGFR mean value was significantly higher compared to IVCCI >40% and IVCCI [less than or equal to] 15% ranges: 70.7 [+ or -] 13 ml/min versus 53.2 [+ or -] 4 and 47.5 [+ or -] 13.6 ml/min/1.73 [m.sup.2]; p (Student-Newman-Keuls test for all pairwise comparisons)<0.05 for both.
The relation between systolic blood pressure (SBP) and IVCCI at admission was also investigated.
Comparison of basal and post- treatment eGFR and IVCCI values
On the contrary, no difference was detected by comparing IVCCI basal and post-infusion mean values: 28.2 [+ or -] 16.7 versus 30 [+ or -] 12%; p (paired samples t-test) = 0.2260.
Furthermore, a curvilinear relationship was detected between basal IVCCI and eGFR values in the study population.
IVCCI as a tool for monitoring of intravascular volume in CHF patients: pathophysiologic basis and literature data
This has been confirmed by a recent study in which an IVCCI [less than or equal to] 15% was highly sensitive and specific for the diagnosis of acute decompensated heart failure, whereas the absolute diameter of the IVC in itself was non-diagnostic (28).
In our study we decided to categorize IVCCI values by grouping them in three classes: [less than or equal to] 15%, 16- 40% and >40%.
While planning the study, we considered that the three IVCCI ranges of our study may reflect also different levels of renal function, so as to reproduce the differences found by comparing eGFRs associated with different levels of invasively measured PVC in another previous study (16).
In addition, in IVCCI [less than or equal to] 15% (12 patients), eGFR at admission showed a sharp increase when IVCCI increased from 1 to 15%.
It could appear striking that as many as 18 among 49 patients on the whole (36.7%) were found to exhibit a pattern of relatively high IVC collapsibility (IVCCI >40%).