Endothelial Glycocalyx and Cardiopulmonary Bypass.

On the outer surface of a human cell there is a dense layer of complex carbohydrates called glycocalyx, also referred to as glycans or the sugar coating on the cell surface, which is composed of a complex array of oligosaccharide and polysaccharide glucose chains that are covalently bonded to proteoglycans and lipids bound to the cell membrane surface. Studies of an intact endothelial glycocalyx layer (EGL) have revealed a number of critical functions that relate the importance of this protective layer to vascular integrity and permeability. These functions include the following: stabilization and maintenance of the vascular endothelium, an active reservoir of essential plasma proteins (i.

Measurement of total hemoglobin reduces red cell transfusion in hospitalized patients undergoing cardiac surgery: a retrospective database analysis.

Introduction: Historically, perioperative hemoglobin monitoring has relied on calculated saturation, using blood gas devices that measure plasma hematocrit (Hct). Co-oximetry, which measures total hemoglobin (tHb), yields a more comprehensive assessment of hemodilution. The purpose of this study was to examine the association of tHb measurement by co-oximetry and Hct, using conductivity with red blood cell (RBC) transfusion, length of stay (LOS) and inpatient costs in patients having major cardiac surgery.

Understanding Off-Label Use and Reference Blood Flows in Modern Membrane Oxygenators.

This editorial will address two issues that are still a source of global controversy and confusion in present day perfusion practice. Membrane oxygenators are designed and tested to a set of stringent flow standards prior to their release from every manufacturer. But how well do we know the iatrogenic consequences of pushing these devices beyond their maximum rated limits? In addition, how well do we know the meaning of the term 'AAMI Reference Flow' as it relates to the Manufacturers Maximum Rated Flow?

Arterial filter bypass loop: what occurs in this area during cardiopulmonary bypass and are there potential patient implications.

The arterial filter is an integral part of bypass circuitry. When introduced, manufacturers suggested a bypass loop for retrograde priming and de-airing, and for uninterrupted blood flow in case of malfunction. Practice has shown antegrade priming and de-airing is possible.

Rationale and use of perfusion variables in the 2010 update of the society of thoracic surgeons congenital heart surgery database.

Patients undergoing congenital heart surgery are at risk of morbidity and mortality. The reasons underlying this risk are complex. To identify opportunities to reduce adverse sequelae, the cardiovascular perfusion community was invited to amend existing perfusion-related fields as well as add new ones to the current version of the Society of Thoracic Surgeons Congenital Heart Surgery Database (STS-CHSD).

The effect of Diprivan (propofol) on phosphorylcholine surfaces during cardiopulmonary bypass--an in vitro investigation.

It is well known that extracorporeal surfaces have the ability to bind such drugs as fentanyl, nitroglycerine and propofol. Adsorption of the injectable anesthetic agent Diprivan (propofol) onto uncoated and heparin-coated extracorporeal surfaces during cardiopulmonary bypass (CPB) has been previously investigated; however, propofol adsorption onto synthetic-coated extracorporeal surfaces has not been published previously. The focus of this investigation was on the interaction of propofol and the synthetic biomimetic coating from the Sorin Group called Mimesys (phosphorylcholine (PC)).

Post-arterial filter gaseous microemboli activity of five integral cardiotomy reservoirs during venting: an in vitro study.

During a previously published study on gaseous microemboli (GMEs) and perfusionist interventions, it was noted that emboli could be detected after the arterial filter when blood/air challenges entered the membrane oxygenator's integral cardiotomy. The findings indicated that further study into the oxygenator's integral cardiotomy reservoir was warranted. This is the first know published report that connects the vent return to GME activity after the arterial filter.

Complications relating to perfusion and extracorporeal circulation associated with the treatment of patients with congenital cardiac disease: consensus definitions from the Multi-Societal Database Committee for Pediatric and Congenital Heart Disease.

The International Consortium for Evidence-Based Perfusion (www.bestpracticeperfusion.org) is a collaborative partnership of societies of perfusionists, professional medical societies, and interested clinicians, whose aim is to promote the continuous improvement of the delivery of care and outcomes for patients undergoing extracorporeal circulation.

Point of care hematocrit and hemoglobin in cardiac surgery: a review.

The use of point-of-care blood gas analyzers in cardiac surgery has been on the increase over the past decade. The availability of these analyzers in the operating room and post-operative intensive care units eliminates the time delays to transport samples to the main laboratory and reduces the amount of blood sampled to measure such parameters as electrolytes, blood gases, lactates, glucose and hemoglobin/hematocrit. Point-of-care analyzers also lead to faster and more reliable clinical decisions while the patient is still on the heart lung machine.

Preventing gaseous microemboli during blood sampling and drug administration: an in vitro investigation.

The detection and prevention of gaseous microemboli (GMEs) during cardiopulmonary bypass has generated considerable interest within the cardiac surgical community. There have been several landmark papers that have used transcranial Doppler devices during cardiopulmonary bypass to detect gaseous microemboli activity in the patients' middle cerebral artery during perfusionist interventions. To determine if this source of emboli could be prevented, a shunt was developed between the oxygenator's sampling manifold and the oxygenator's venous line.

Clinical evaluation of the Sorin Synthesis oxygenator with integrated arterial filter.

The use of arterial line filters has long been a standard of practice in the field of cardiopulmonary bypass. Sorin Biomedica has designed an adult hollow-fiber oxygenator that not only incorporates their Mimesys biomimicry coating technology but also has a 40-micron arterial filter as an integrated component of this unique membrane oxygenator. We did a prospective, randomized clinical trial of 54 Synthesis coated oxygenators and compared them with 54 uncoated Monolyth Pro oxygenators, the latter of which incorporated an external arterial line filter with a standard bypass loop There were few statistically significant differences found between the Synthesis group and the Monolyth group with regard to pressure differentials, hemodynamic resistance, and platelet drop.

A multicenter investigation into the occurrence of high-pressure excursions.

The occurrence of sudden increases in premembrane pressures and membrane pressure differentials has drawn considerable attention and debate in the perfusion community. Several terms have been applied to this phenomenon, but the term that best describes this event is "high-pressure excursion" (HPE). The exact causes of HPE are still uncertain, but nonetheless widely speculated.

Evaluation of Mimesys phosphorylcholine (PC)-coated oxygenators during cardiopulmonary bypass in adults.

A new generation of coating extracorporeal circuitry with biocompatible polymers has entered the North American perfusion market. This new biomimetic coating process uses synthetic phosphorylcholine (PC) containing polymers to bond covalently to the surface of the Sorin Monolyth oxygenator, under the brand name of Mimesys. In part one of a three-part investigation, 160 Mimesys-coated oxygenators were randomly evaluated against 36 uncoated oxygenators for blood flow, hemodynamic resistance, and pressure differentials.