Olivier Desebbe

High-volume haemofiltration with a new haemofiltration membrane having enhanced adsorption properties in septic pigs

BACKGROUNDnHigh-volume haemofiltration (HVHF) has been suggested as an adjuvant treatment of septic shock due to its capacities to remove from blood both pro- and anti-inflammatory mediators involved in the sepsis syndrome. Adsorption properties of some haemofiltration membranes are also interesting with this indication because inflammatory mediators are caught in the membrane itself. The aim of this study was to determine the haemodynamic and immunological effects of a new haemofiltration membrane, which has enhanced adsorption properties due to a special surface treatment, allowing the adsorption of endotoxins.nnnMETHODSnWe compared this membrane to a standard haemofiltration membrane both in vitro and in 20 sepsis-induced pigs, randomized in two groups. One group was haemofiltered with the treated membrane and the other with the standard haemofiltration membrane during 6-h HVHF sessions.nnnRESULTSnAt the end of the experiment, mean +/- SD crystalloids requirements (5937 +/- 1588 versus 7587 +/- 1456 ml, P = 0.026), colloids requirements (1437 +/- 320 versus 1912 +/- 538 ml, P = 0.027), lactic acidosis (pH = 7.20 +/- 0.11 versus 7.10 +/- 0.07, P = 0.026) and pulmonary arterial hypertension (MPAP = 24 +/- 7 versus 34 +/- 8 mmHg, P = 0.008) were less pronounced when HVHF was performed with the treated membrane. In addition, mean +/- SD endotoxins levels were lower in the treated membrane group after 1 hour of HVHF (1.91 +/- 1.19 versus 11.07 +/- 10.64 EU/ml, P = 0.035). Cytokines levels were not different between groups except for IL-1beta, which was slightly lower in the treated membrane group.nnnCONCLUSIONSnThe use of a membrane with enhanced adsorption properties during a 6-h HVHF session in septic pigs improves haemodynamics compared to a standard haemofiltration membrane. These results are probably due to an efficient endotoxins and cytokines adsorption. A human study using this membrane is now necessary to confirm these results.

Effect of Levosimendan on Low Cardiac Output Syndrome in Patients With Low Ejection Fraction Undergoing Coronary Artery Bypass Grafting With Cardiopulmonary Bypass: The LICORN Randomized Clinical Trial

Importance Low cardiac output syndrome after cardiac surgery is associated with high morbidity and mortality in patients with impaired left ventricular function. Objective To assess the ability of preoperative levosimendan to prevent postoperative low cardiac output syndrome. Design, Setting, and Participants Randomized, double-blind, placebo-controlled trial conducted in 13 French cardiac surgical centers. Patients with a left ventricular ejection fraction less than or equal to 40% and scheduled for isolated or combined coronary artery bypass grafting with cardiopulmonary bypass were enrolled from June 2013 until May 2015 and followed during 6 months (last follow-up, November 30, 2015). Interventions Patients were assigned to a 24-hour infusion of levosimendan 0.1 µg/kg/min (nu2009=u2009167) or placebo (nu2009=u2009168) initiated after anesthetic induction. Main Outcomes and Measures Composite end point reflecting low cardiac output syndrome with need for a catecholamine infusion 48 hours after study drug initiation, need for a left ventricular mechanical assist device or failure to wean from it at 96 hours after study drug initiation when the device was inserted preoperatively, or need for renal replacement therapy at any time postoperatively. It was hypothesized that levosimendan would reduce the incidence of this composite end point by 15% in comparison with placebo. Results Among 336 randomized patients (mean age, 68 years; 16% women), 333 completed the trial. The primary end point occurred in 87 patients (52%) in the levosimendan group and 101 patients (61%) in the placebo group (absolute risk difference taking into account center effect, −7% [95% CI, −17% to 3%]; Pu2009=u2009.15). Predefined subgroup analyses found no interaction with ejection fraction less than 30%, type of surgery, and preoperative use of &bgr;-blockers, intra-aortic balloon pump, or catecholamines. The prevalence of hypotension (57% vs 48%), atrial fibrillation (50% vs 40%), and other adverse events did not significantly differ between levosimendan and placebo. Conclusions and Relevance Among patients with low ejection fraction who were undergoing coronary artery bypass grafting with cardiopulmonary bypass, levosimendan compared with placebo did not result in a significant difference in the composite end point of prolonged catecholamine infusion, use of left ventricular mechanical assist device, or renal replacement therapy. These findings do not support the use of levosimendan for this indication. Trial Registration EudraCT Number: 2012-000232-25; clinicaltrials.gov Identifier: NCT02184819

Relations between respiratory changes in R-wave amplitude and arterial pulse pressure in mechanically ventilated patients.

IntroductionR-wave obtained from the electrocardiogram depends on ventricular stroke volume. We assessed the relationship between respiratory variations in R-wave (ΔRDII) and in pulse pressure (ΔPP) during general anesthesia.MethodR-wave amplitude was measured from standard lead II (RDII). Maximal RDII (RDIImax) and minimal RDII (RDIImin) were determined over one respiratory cycle. ΔRDII was calculated as 100 × [RDIImax-RDIImin]/([RDIImax +xa0RDIImin]/2. ΔRDII and ΔPP were simultaneously recorded.ResultsThere was a significant relationship (rxa0=xa00.79; P < 0.001) between ΔRDII and ΔPP. A ΔRDII > 13% detected patients with a ΔPP > 13% with an 89% sensitivity, and an 88% specificity.ConclusionΔRDII and ΔPP are related in this setting.

Respiratory variation in aortic blood flow peak velocity to predict fluid responsiveness in mechanically ventilated children: a systematic review and meta-analysis.

Dynamic indices of preload have been shown to better predict fluid responsiveness than static variables in mechanically ventilated adults. In children, dynamic predictors of fluid responsiveness have not yet been extensively studied.