Background Fluid challenges (FCs) are one of the most commonly used therapies in critically ill patients and represent the cornerstone of hemodynamic management in intensive care units. There are clear benefits and harms from fluid therapy. Limited data on the indication, type, amount and rate of an FC in critically ill patients exist in the literature. The primary aim was to evaluate how physicians conduct FCs in terms of type, volume, and rate of given fluid; the secondary aim was to evaluate variables used to trigger an FC and to compare the proportion of patients receiving further fluid administration based on the response to the FC. Methods This was an observational study conducted in ICUs around the world. Each participating unit entered a maximum of 20 patients with one FC. Results 2213 patients were enrolled and analyzed in the study. The median [interquartile range] amount of fluid given during an FC was 500 ml (500–1000). The median time was 24 min (40–60 min), and the median rate of FC was 1000 [500–1333] ml/h. The main indication for FC was hypotension in 1211 (59 %, CI 57–61 %). In 43 % (CI 41–45 %) of the cases no hemodynamic variable was used. Static markers of preload were used in 785 of 2213 cases (36 %, CI 34–37 %). Dynamic indices of preload responsiveness were used in 483 of 2213 cases (22 %, CI 20–24 %). No safety variable for the FC was used in 72 % (CI 70–74 %) of the cases. There was no statistically significant difference in the proportion of patients who received further fluids after the FC between those with a positive, with an uncertain or with a negatively judged response. Conclusions The current practice and evaluation of FC in critically ill patients are highly variable. Prediction of fluid responsiveness is not used routinely, safety limits are rarely used, and information from previous failed FCs is not always taken into account.

Sepsis, defined as life-threatening organ dysfunction caused by a dysregulated host response to infection, remains the most common cause of death in critically ill patients.¹ Numerous therapies intended to target the various biological pathways of sepsis have been tested in large randomized studies, but none have shown a significant benefit on mortality.^2-4

To evaluate the effects of continuous infusion of methylene blue (MB), an inhibitor of the nitric oxide pathway, on hemodynamics and organ functions in human septic shock. Prospective, randomized, controlled, open-label, pilot study. Multidisciplinary intensive care unit of a university hospital. Twenty patients with septic shock diagnosed <24 hrs before randomization. Patients were randomized 1:1 to receive either MB (MB group, n = 10) or isotonic saline (control group, n = 10), adjunctive to conventional treatment. MB was administered as an intravenous bolus injection (2 mg/kg), followed 2 hrs later by infusion at stepwise increasing rates of 0.25, 0.5, 1, and 2 mg/kg/hr that were maintained for 1 hr each. During infusion, mean arterial pressure was maintained between 70 and 90 mm Hg, while attempting to reduce concurrent adrenergic support. Hemodynamics and organ function variables were assessed over a 24-hr period, and the survival rate at day 28 was noted. Infusion of MB prevented the stroke volume and the left-ventricular stroke work indexes from falling and increased mean arterial pressure. Compared with the control group, MB reduced the requirement for norepinephrine, epinephrine, and dopamine by as much as 87%, 81%, and 40%, respectively. Oxygen delivery remained unchanged in the MB group and decreased in the control group. MB also reduced the body temperature and the plasma concentration of nitrates/nitrites. Leukocytes and organ function variables such as bilirubin, alanine aminotransferase, urea, and creatinine were not significantly affected. Platelet count decreased in both groups. Five patients treated with MB survived vs. three patients receiving conventional treatment. In human septic shock, continuously infused MB counteracts myocardial depression, maintains oxygen transport, and reduces concurrent adrenergic support. Infusion of MB appears to have no significant adverse effects on the selected organ function variables.

Introduction: Several single-center studies and meta-analyses have shown that perioperative goal-directed therapy may significantly improve outcomes in general surgical patients. We hypothesized that using a treatment algorithm based on pulse pressure variation, cardiac index trending by radial artery pulse contour analysis, and mean arterial pressure in a study group (SG), would result in reduced complications, reduced length of hospital stay and quicker return of bowel movement postoperatively in abdominal surgical patients, when compared to a control group (CG). Methods: 160 patients undergoing elective major abdominal surgery were randomized to the SG (79 patients) or to the CG (81 patients). In the SG hemodynamic therapy was guided by pulse pressure variation, cardiac index trending and mean arterial pressure. In the CG hemodynamic therapy was performed at the discretion of the treating anesthesiologist. Outcome data were recorded up to 28 days postoperatively. Results: The total number of complications was significantly lower in the SG (72 vs. 52 complications, p = 0.038). In particular, infection complications were significantly reduced (SG: 13 vs. CG: 26 complications, p = 0.023). There were no significant differences between the two groups for return of bowel movement (SG: 3 vs. CG: 2 days postoperatively, p = 0.316), duration of post anesthesia care unit stay (SG: 180 vs. CG: 180 minutes, p = 0.516) or length of hospital stay (SG: 11 vs. CG: 10 days, p = 0.929). Conclusions: This multi-center study demonstrates that hemodynamic goal-directed therapy using pulse pressure variation, cardiac index trending and mean arterial pressure as the key parameters leads to a decrease in postoperative complications in patients undergoing major abdominal surgery. Trial registration: ClinicalTrial.gov, NCT01401283.

To find out if the extravascular lung water index (EVLWI) and the derived permeability indexes determined by the single transpulmonary thermodilution technique are associated with markers of acute lung injury in human septic shock. Prospective, observational study. Mixed intensive care unit of a 900-bed university hospital. Thirty-eight consecutive adult patients with septic shock and acute lung injury. None. The variables were assessed over a 72-hr period and included hemodynamics, EVLWI, and pulmonary vascular permeability indexes determined with the single indicator transpulmonary thermodilution technique, lung compliance, oxygenation ratio (Pao2/Fio2), lung injury score, cell counts, and the plasma concentration of endothelin-1. At day 1, EVLWI was elevated (>or=7 mL/kg) in 28 (74%) patients and correlated with lung compliance (r=-.48, p=.002), Pao2/Fio2 (r=-.50, p=.001), lung injury score (r=.46, p=.004), roentgenogram quadrants (r=.39, p=.02), and platelet count (r=-.43, p=.007). At day 3, EVLWI correlated with compliance (r=-.51, p=.002), Pao2/Fio2 (r=-.49, p = .006), and lung injury score (r=.53, p=.003). At day 3, EVLWI and pulmonary vascular permeability indexes were higher in nonsurvivors (p<.05). The plasma concentration of endothelin-1 (mean+/-sd) was significantly higher in patients with elevated EVLWI (>or=7 mL/kg) (3.85+/-1.40 vs. 2.07+/-0.38 pg/mL, respectively). Twenty-two (59%) patients died before day 28. In human septic shock, EVLWI demonstrated moderate correlation with markers of acute lung injury, such as lung compliance, oxygenation ratio, roentgenogram quadrants, and lung injury score. In nonsurvivors, EVLWI and permeability indexes were significantly increased at day 3. Thus, EVLWI might be of value as an indicator of prognosis and severity of sepsis-induced acute lung injury.