ABSTRACT
OBJECTIVE: Red-cell distribution width (RDW) has been identified as a novel prognostic marker in a heterogeneous group of heart failure patients. In this group, diastolic dysfunction is associated with worse outcome. As the evidence is limited, the aim of the present study was to assess the relationship of RDW to diastolic markers in patients with left ventricular dysfunction (LVD) diagnosed during cardiac catheterization. METHODS: Clinical and angiographic data were collected retrospectively on a total of 291 stable patients (mean age 62 years, 199 males) with systolic dysfunction documented during cardiac catheterization in a regional medical center between January 2006 and December 2010. RESULTS: Positive association was seen between RDW and Left ventricular end diastolic pressure (LVEDP), estimated systolic pulmonary arterial pressure(sPAP), and left atrial dimension (LAD) (r: 0.18, 0.24, 0.28, respectively; p:<0.05).Three year retrospective survival analysis for 108 patients admitted in the first 2 years showed a statistically significant decrease in survival patients with high RDW(> 14.5) vs. normal RDW (73%vs.88%;log rank p:0.03). This was seen even in the asymptomatic subgroup (71% vs. 94%; log rank p: 0.01). CONCLUSION: RDW correlates with markers of diastolic dysfunction in patients with LVD. Additionally, in patients asymptomatic LVD, high RDW is still associated with lower survival.
ABSTRACT
Severe hypophosphatemia is known to be associated with respiratory failure, but there are few studies that specifically examine the relationship between serum phosphorus concentration and failure to wean patients from mechanical ventilation. This study investigated the association between hypophosphatemia and weaning failure in patients in two medical intensive care units (ICU). The study was conducted in a prospectively developed cohort of 66 patients being treated with ventilatory support and in whom 193 weaning trials were attempted. Ultimately, all 66 subjects were successfully weaned. A cross-sectional analysis was conducted on serum phosphorus levels and success or failure to wean the patients from ventilators. At the time of the successful weaning attempts (n = 66), the subjects' serum phosphorus concentrations (mean +/- SD) were 1.18 +/- 0.27 mmol/L, whereas at all failed weaning attempts (n = 127) serum phosphorus concentrations averaged 1.06 +/- 0.31 mmol/L (p = 0.008). Subjects with phosphorus concentrations below the reference interval (RI) in our laboratory (<0.80 mmol/L) had greater risk for weaning failure compared to subjects with phosphorus concentrations at or above the RI (relative risk = 1.18; 95% confidence interval = 1.06 to 1.32; p = 0.01). Serum calcium concentrations were not significantly different at the time of successful weaning compared to those at failed weaning attempts. This study indicates that there is an association between hypophosphatemia and failure-to-wean from mechanical ventilation in ICU patients on ventilatory support.
