Effects of paracentesis on hemodynamic parameters and respiratory function in critically ill patients.

BACKGROUND: Ascites is a major and common complication of liver cirrhosis. Large or refractory ascites frequently necessitates paracentesis. The aim of our study was to investigate the effects of paracentesis on hemodynamic and respiratory parameters in critically ill patients. METHODS: Observational study comparing hemodynamic and respiratory parameters before and after paracentesis in 50 critically ill patients with advanced hemodynamic monitoring. 28/50 (56%) required mechanical ventilation.Descriptive statistics are presented as mean ± standard deviation for normally distributed data and median, range, and interquartile range (IQR) for non-normally distributed data. Comparisons of hemodynamic and respiratory parameters before and after paracentesis were performed by Wilcoxon signed-rank tests. Bivariate relations were assessed by Spearman's correlation coefficient and univariate regression analyses. RESULTS: Median amount of ascites removed was 5.99 L (IQR, 3.33-7.68 L). There were no statistically significant changes in hemodynamic parameters except a decrease in mean arterial pressure (-7 mm Hg; p = 0.041) and in systemic vascular resistance index (-116 dyne·sec/cm5/m2; p = 0.016) when measured 2 hours after paracentesis. In all patients, oxygenation ratio (PaO2/FiO2; median, 220 mmHg; IQR, 161-329 mmHg) increased significantly when measured immediately (+58 mmHg; p = 0.001), 2 hours (+9 mmHg; p = 0.004), and 6 hours (+6 mmHg); p = 0.050) after paracentesis. In mechanically ventilated patients, lung injury score (cumulative points without x-ray; median, 6; IQR, 4-7) significantly improved immediately (5; IQR, 4-6; p < 0.001), 2 hours (5; IQR, 4-7; p = 0.003), and 6 hours (6; IQR 4-6; p = 0.012) after paracentesis. CONCLUSION: Paracentesis in critically ill patients is safe regarding circulatory function and is related to immediate and sustained improvement of respiratory function.

Impact of large-volume thoracentesis on transpulmonary thermodilution-derived extravascular lung water in medical intensive care unit patients.

PURPOSE: The purpose of this study was to investigate the impact of large-volume thoracentesis (>1000 mL) on transpulmonary thermodilution (TPTD)-derived cardiopulmonary parameters with special regard to extravascular lung water index (EVLWI). MATERIALS AND METHODS: Retrospective analysis of a prospectively maintained database including TPTD measurements of patients treated in a medical intensive care unit of a German university hospital between January 2009 and September 2010. Data of 17 patients treated with large-volume thoracentesis were analyzed. RESULTS: A median of 1350 (25%-75% interquartile range [IQR], 1200-1590) mL of pleural fluid was removed. Extravascular lung water index was statistically significantly higher after thoracentesis compared with baseline (9.0 [IQR, 8.0-13.0] vs 8.0 [IQR, 7.0-13.0] mL/kg) (P = .039). Pulmonary vascular permeability index (PVPI) also increased significantly after thoracentesis (1.7 [IQR, 1.3-2.4] vs 1.4 [IQR, 1.1-2.1]) (P = .019). When determined 2 and 6 hours after thoracentesis, EVLWI and PVPI even further increased. Six hours after removal of pleural fluid, we observed a median EVLWI of 11.0 (IQR, 8.0-15.0) mL/kg (P = .048 compared with baseline) and a median PVPI of 2.0 (IQR, 1.5-2.7) (P = .040 compared with baseline). CONCLUSIONS: Large-volume thoracentesis results in a statistically significant increase in TPTD-derived EVLWI. Because EVLWI was higher after removal of pleural fluid, we conclude that pleural effusions do not take part in single-indicator TPTD as a part of the pulmonary thermovolume and do not increase TPTD-derived EVLWI.