The Journal of extra-corporeal technology
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J Extra Corpor Technol · Mar 2015
Case ReportsVariability in End-Organ Perfusion with Femoral-Femoral Venoarterial Extracorporeal Membrane Oxygenation: Aortographic Evidence.
In femoral-femoral venoarterial extracorporeal membrane oxygenation (VA-ECMO), the outflow of oxygenated blood from the circuit enters the aorta in retrograde fashion. As a result, variability in end-organ oxygenation (e.g., cerebral vs. splanchnic) may arise-particularly, when the heart is unable to contribute forward flow. We present the case of a 74-year-old man supported by femoral-femoral VA-ECMO in whom aortography was used to visualize the retrograde distribution of arterial ECMO flow that can produce such differences in end-organ perfusion. We do this by describing a series of still images captured during the aortography; we then discuss the importance of monitoring end-organ oxygenation in this setting and outline several interventions that can ameliorate this flow phenomenon.
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J Extra Corpor Technol · Mar 2015
Case ReportsManagement of Heparin-Resistant Patients with Benefits? Maximizing Biocompatibility in Cardiopulmonary Bypass: Combining ATryn® Recombinant Antithrombin III and Carmeda® Heparin-Bonded Perfusion Circuits: A Case Series.
As many as 25% of our cardiopulmonary bypass (CPB) patients have a diminished heparin response and fail to reach a therapeutic activated clotting time (ACT). We treat a majority of these patients with antithrombin III (ATryn®, recombinant antithrombin III [rhAT], rEVO Biologics). Our current CPB circuit uses Medtronic Carmeda® coating. ⋯ We also observed decreased postoperative atrial fibrillation rates, improved platelet preservation, decreased intensive care unit and ventilator times in patients receiving rhAT compared to rates commonly observed at our center. Heparin-resistant patients can be treated with rhAT to achieve therapeutic ACTs. Our observations suggest that the use of rhAT in conjunction with Carmeda® heparin-bonded circuits may also have a positive benefit on some of the well-established negative clinical consequences of CPB and improve patient outcomes.
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J Extra Corpor Technol · Mar 2015
EditorialPerspective on Cerebral Microemboli in Cardiac Surgery: Significant Problem or Much Ado About Nothing?
From the time an association was perceived between cardiac surgery and post-operative cognitive dysfunction (POCD), there has been interest in arterial microemboli as one explanation. A succession of studies in the mid-1990s reported a correlation between microemboli exposure and POCD and there followed a focus on microemboli reduction (along with other strategies) in pursuit of peri-operative neuroprotection. There is some evidence that the initiatives developed during this period were successful in reducing neurologic morbidity in cardiac surgery. ⋯ Improvements in CPB safety (including emboli reduction) achieved over the last 20 years may be partly responsible for difficulty demonstrating higher rates of POCD after cardiac surgery involving CPB in contemporary comparisons with other operations. Moreover, microemboli (including bubbles) have been proven harmful in experimental and clinical situations uncontaminated by other confounding factors. It remains important to continue to minimize patient exposure to microemboli as far as is practicable.
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J Extra Corpor Technol · Mar 2015
Editorial20 Years On: Is It Time to Redefine the Systemic Inflammatory Response to Cardiothoracic Surgery?
The "systemic inflammatory response" has never been defined from a cardiothoracic surgery perspective, but borrowed its definition from the critical care field at a landmark 1992 definition conference on sepsis. It is unclear why the diagnostic criteria for the Systemic Inflammatory Response Syndrome (SIRS) were adopted in isolation, ignoring other potentially more useful definitions for Severe Septic Shock or Secondary Multiple Organ Dysfunction Syndrome. The 1992 SIRS definition for sepsis has since been updated at a conference in 2001 advocating PIRO (Predisposition, Infection, host Response, Organ dysfunction) as a hypothetical model to better link sepsis with clinical outcome. ⋯ The name "inflammatory response" is also problematic; it is too narrow and might be replaced with host response (the R in PIRO) to better convey the wide spectrum of host defensive pathways activated during heart surgery (i.e., complement, coagulation, fibrinolysis, kinins, cytokines, proteases, hemolysis, oxidative stiess). A variant on PIRO could allow these elements of the host Response (R) to be anchored within the context of Premorbid conditions (P) and the inevitable Insult (I) from surgery, to better link risk exposures to Organ dysfunction (O) in heart surgery. The precedent of PIRO suggests the following steps will be required to redefine the systemic inflammatory response: 1) buy-in from the leading societies for cardiothoracic surgery, anesthesia, and perfusion on the need for a re-definition conference, 2) assigning relative risk scores to different premorbid exposures, operative insults, and host response factors on clinical outcome, 3) validation of the risk model in a prospective cohort, and 4) development of algorithms or "apps" to facilitate rapid diagnosis and staging of care at bedside.
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J Extra Corpor Technol · Dec 2014
Randomized Controlled TrialInfluence of Two Colloidal Extracorporeal Primes on Coagulation of Cardiac Surgical Patients: A Prospectively Randomized Open-Label Pilot Trial.
The search for the ideal priming fluid continues as more evidence is discovered about side effects of volume expanders. With the availability of modern, balanced hydroxyethyl starch (HES) solutions with less side effects than former HES solutions, we considered to replace our gelatin- (modified gelatin) based extracorporeal circuit prime for a HES (130/.42) prime. Therefore, we studied the influence of two colloidal priming fluids on postoperative coagulation in patients undergoing cardiac surgery. ⋯ We found no significant difference in colloid. osmotic pressure between the groups. In this trial, HES (130/.42) impairs coagulation significantly more compared with gelatin. These differences in influence on coagulation did not lead to a difference in blood loss or fluid balance, so clinical relevance could not be proven.