Storage of bronchoalveolar lavage fluid and accuracy of microbiologic diagnostics in the ICU: a prospective observational study

Introduction: Early initiation of appropriate antimicrobial treatment is a cornerstone in managing pneumonia. Because microbiologic processing may not be available around the clock, optimal storage of specimens is essential for accurate microbiologic identification of pathogenetic bacteria. The aim of our study was to determine the accuracy of two commonly used storage approaches for delayed processing of bronchoalveolar lavage in critically ill patients with suspected pneumonia. Methods: This study included 132 patients with clinically suspected pneumonia at two medical intensive care units of a tertiary care hospital. Bronchoalveolar lavage samples were obtained and divided into three aliquots: one was used for immediate culture, and two, for delayed culture (DC) after storage for 24 hours at 4 degrees C (DC4) and -80 degrees C (DC-80), respectively. Results: Of 259 bronchoalveolar lavage samples, 84 (32.4\%) were positive after immediate culture with 115 relevant culture counts (>= 10(4) colony-forming units/ml). Reduced (<10(4) colony-forming units/ml) or no growth of four and 57 of these isolates was observed in DC4 and DC-80, respectively. The difference between mean bias of immediate culture and DC4 (-0.035; limits of agreement, -0.977 to 0.906) and immediate culture and DC-80 (-1.832; limits of agreement, -4.914 to 1.267) was -1.788 +/- 1.682 (P < 0.0001). Sensitivity and negative predictive value were 96.5\% and 97.8\% for DC4 and 50.4\% and 75.4\% for DC-80, respectively; the differences were statistically significant (P < 0.0001). Conclusions: Bronchoalveolar lavage samples can be processed for culture when stored up to 24 hours at 4 degrees C without loss of diagnostic accuracy. Delayed culturing after storage at -80 degrees C may not be reliable, in particular with regard to Gram-negative bacteria

Parameters associated with therapeutic response using peritoneal dialysis for therapy refractory heart failure and congestive right ventricular dysfunction.

BACKGROUND:In patients with refractory heart failure (HF) peritoneal dialysis (PD) is associated with improved functional status and decrease in hospitalization. However, previous studies did not focus on right ventricular dysfunction as an important pathophysiologic component of cardiorenal syndrome. METHODS:In a prospective cohort study PD was started in 40 patients with refractory right HF (with/without left HF). Refractoriness to conservative therapy was defined as persistent right heart congestion/ascites with intensified diuretic treatment and/or ≥2 hospitalizations within 6 months because of cardiac decompensation despite optimal medical treatment, and/or acute renal failure during intensified conservative treatment of cardiac decompensations. RESULTS:Patient survival was 55.0% at 1 year, 35.0% at 2 years and 27.5% at 3 years. The number of hospitalization days declined after initiation of PD for both cardiac [13 (IQR 1-53) days before vs. 1 (IQR 0-12) days after start of PD, p<0.001] and unplanned reasons [12 (IQR 3-44) days before vs. 1 (IQR 0-33) days after start of PD, p = 0.007]. Using a combined endpoint including survival time of ≥1 year and either improvement in quality of life or decline in hospitalizations we found that patients with extended ascites, higher systolic pulmonary artery pressure, more marked impairment of right ventricular function and tricuspid valve insufficiency, higher residual renal function as well as those who could perform PD without assistance have benefited most from this therapy. CONCLUSIONS:Patients with more pronounced backward failure, less marked residual renal functional impairment and those not depending on assistance for therapy are likely to profit most from PD

Acute Hemodynamic Effects of Riociguat in Patients With Pulmonary Hypertension Associated With Diastolic Heart Failure (DILATE-1)

BACKGROUND: Deficient nitric oxide-soluble guanylate cyclase-cyclic guanosine monophosphate signaling results from endothelial dysfunction and may underlie impaired cardiac relaxation in patients with heart failure with preserved left ventricular ejection fraction (HFpEF) and pulmonary hypertension (PH). The acute hemodynamic effects of riociguat, a novel soluble guanylate cyclase stimulator, were characterized in patients with PH and HFpEF. METHODS: Clinically stable patients receiving standard HF therapy with a left ventricular ejection fraction. 50%, mean pulmonary artery pressure (mPAP) >= 25 mm Hg, and pulmonary arterial wedge pressure (PAWP). 15 mm Hg at rest were randomized to single oral doses of placebo or riociguat (0.5, 1, or 2 mg). The primary efficacy variable was the peak decrease in mPAP from baseline up to 6 h. Secondary outcomes included hemodynamic and echocardiographic parameters, safety, and pharmacokinetics. RESULTS: There was no significant change in peak decrease in mPAP with riociguat 2 mg (n = 10) vs placebo (n = 11, P = .6). However, riociguat 2 mg significantly increased stroke volume (1 9 mL [95% CI, 0.4-17]; P = .04) and decreased systolic BP (-12 mm Hg [95% CI, -22 to -1]; P = .03) and right ventricular end-diastolic area (-5.6 cm(2) [95% CI, -11 to -0.3]; P = .04), without significantly changing heart rate, PAWP, transpulmonary pressure gradient, or pulmonary vascular resistance. Riociguat was well tolerated. CONCLUSIONS: In patients with HFpEF and PH, riociguat was well tolerated, had no significant effect on mPAP, and improved exploratory hemodynamic and echocardiographic parameters