Objective: Mortality in patients with cardiogenic shock after out-of-hospital cardiac arrest remains high despite advances in resuscitation and early revascularization strategies. Recent studies suggest a reduced mortality in survivors of cardiac arrest subjected to mild therapeutic hypothermia, but the underlying mechanisms are not yet clear. Because positive hemodynamic effects of mild therapeutic hypothermia have been suggested, we aimed at testing the hypothesis that patients in cardiogenic shock might benefit from mild therapeutic hypothermia.
Methods: Hemodynamic effects of mild therapeutic hypothermia in 20 consecutive patients admitted in cardiogenic shock after successful resuscitation from out-of-hospital cardiac arrest were investigated. A historic normothermic control group was matched (one-to-one) by means of a propensity score. Patients were cooled to 33°C for 24 hrs using an endovascular cooling device and hemodynamic variables were continuously recorded by means of pulse contour analysis. Cardiac performance was determined by echocardiography.
Results: Mild therapeutic hypothermia induced a significant decrease in heart rate from 74 to 64 beats per minute. Despite the reduction in heart rate, cardiac index remained unchanged under mild therapeutic hypothermia likely due to an increase in ejection fraction from 43 ± 4% to 55 ± 4%. Mean arterial pressure increased rapidly from 75 ± 2 mm Hg to 84 ± 3 mm Hg (p = .001) upon induction of hypothermia paralleled by an initial increase in systemic vascular resistance. Accordingly, patients with mild therapeutic hypothermia required lower cumulative doses of vasopressors and inotropes.
Conclusions: We conclude that in cardiogenic shock mild therapeutic hypothermia provides circulatory support and an increase in systemic vascular resistance that leads to reduced vasopressor use and may result in lower oxygen consumption. These findings suggest that mild therapeutic hypothermia could be a therapeutic option in hemodynamically unstable patients independent of cardiac arrest and further randomized clinical studies are needed.Link to article
Objective: We compared two polymethylpentene oxygenators being used in our unit: the Maquet Quadrox-iD paediatric® and the Medos Hilite 800LT®.
Study design: A mono-centric, prospective pilot study was conducted on ten consecutive newborn patients who had been admitted to our hospital service for extracorporeal circulation (EC) treatment. We examined the rate of oxygen transfer, the CO2 removal capacity and the average sweep gas flow required to produce this result. We also assessed the disturbances of haemostasis, the need for labile blood products and the membrane oxygenator lifetime and cost of use.
Conclusions: According to our study, it seems to us that Medos Hilite 800LT® membrane oxygenators demonstrate greater oxygen transfer and CO2 removal capacity than Maquet Quadrox-iD paediatric® membrane oxygenators, at a similar cost. These results lead us to conclude that it is reasonable to continue using Medos Hilite 800LT® membrane oxygenators. A broader comparison study would be necessary in order to support these initial results.
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Objectives: This experiment sought to compare two polymethyl pentene (PMP) hollow-fiber membrane oxygenators: the Medos HILITE 2400 LT and the Maquet Quadrox-iD Pediatric in terms of transmembrane pressure gradients and hemodynamic energy preservation under both pulsatile and non-pulsatile conditions.
Methods: A simulated pediatric extracorporeal life support (ECLS) circuit was used to test these two oxygenators. The circuit consisted of a roller pump, ¼ inch tubing for both arterial and venous lines, an oxygenator, and a venous reservoir served as a pseudo-patient. Three pressure transducers were placed upstream and downstream of the oxygenator and the distal arterial line. The experimental system was primed with lactated Ringer’s solution and packed human red blood cells to maintain a hematocrit of 40%.The total volume was 600 ml, including the 350 ml volume of the pseudo-patient.The tests were performed at six flow rates (250, 500, 750, 1000, 1250, 1500 ml/min) and three distal arterial line pressures (MAP) (60, 80, 100 mmHg), under both pulsatile and non-pulsatile perfusion modes.The temperature was kept constant at 37°C for all tests.
Results: Both oxygenators had adequate performances in pressure drop and hemodynamic energy preservation. There were no significant differences between pre- and post-oxygenators for mean pressure (MP), energy equivalent pressure (EEP) and total hemodynamic energy (THE). During the pulsatile perfusion mode, the HILITE 2400 LT retained a greater percentage of surplus hemodynamic energy (SHE) across the oxygenator.
Conclusions: Both the Quadrox-iD Pediatric and HILITE 2400LT PMP membrane oxygenators are suitable for pediatric ECLS therapy under both non-pulsatile and pulsatile perfusion. An optimized combination of flow rate and MAP should be achieved in order to deliver the maximal pulsatile energy in the extracorporeal circuit.Link to article