The Inflammatory Response to Miniaturised Extracorporeal Circulation: A Review of the Literature

Abstract

Conventional cardiopulmonary bypass can trigger a systemic inflammatory response syndrome similar to sepsis. Aetiological factors include surgical trauma, reperfusion injury, and, most importantly, contact of the blood with the synthetic surfaces of the heart-lung machine. Recently, a new cardiopulmonary bypass system, mini-extracorporeal circulation (MECC), has been developed and has shown promising early results in terms of reducing this inflammatory response. It has no venous reservoir, a reduced priming volume, and less blood-synthetic interface. This review focuses on the inflammatory and clinical outcomes of using MECC and compares these to conventional cardio-pulmonary bypass (CCPB). MECC has been shown to reduce postoperative cytokines levels and other markers of inflammation. In addition, MECC reduces organ damage, postoperative complications and the need for blood transfusion. MECC is a safe and viable perfusion option and in certain circumstances it is superior to CCPB.

The impact on neurological outcomes with the new-generation membrane oxygenators with integrated arterial filters

“…This was based on the fact that the MoCA can be easily utilized in a busy clinical practice and enables health professionals to identify mild cognitive impairment through practical administration and interpretation steps. [5] Prolonged intensive care unit stay due to any reason, hemodynamic instability, and cerebrovascular event history were also among the exclusion criteria, which significantly limit the generalizability of our results to all patients undergoing cardiac surgery. In addition, ultrasonographic measurement of the gaseous micro-emboli at the entry of the venous site and way out of the arterial site might provide us more valuable results.…”

“…[4] Several strategies have been developed to minimize the entry of micro-bubbles into ECC, and to decrease the surface area as well as the prime volume. [5,6] New generation oxygenators with integrated arterial filters which allow the incorporation of arterial filters into the oxygenators have been reported to decrease cerebral injury through entrapment of the particulate matter and micro-bubbles. [7,8] Integration of arterial-line filters with oxygenators as a novel CPB design was contrived for integrating the concepts of "surface covering", "blood filtration", and "miniature".…”

Cardiopulmonary Bypass with Low- Versus High-Priming Volume: Comparison of Inflammatory Responses in a Rat Model

“…[17][18][19][20] Minimal extracorporeal circulation technology includes shorter tubes, which decreases PV. The additional benefits of such technology include a decrease in the coagulation cascade and a reduction in the need for blood transfusions in patients undergoing cardiac surgery.…”

“…The additional benefits of such technology include a decrease in the coagulation cascade and a reduction in the need for blood transfusions in patients undergoing cardiac surgery. [17][18][19][20] This technology should become more important and become even more popular in the future. However, our data suggested that the duration of CPB exposure is an important factor in eliciting the systemic inflammatory response in addition to blood contacting artificial surfaces.…”

Miniaturized Extracorporeal Circulation

“…These characteristics lead to a circuit prime volume smaller than standard ECC, ranging between 200-650 ml for the MECC against 1200-1600 ml for the standard ECC (Formica et al 2009Remady et al 2006). The combination of short length tubing, heparin pre-treatment, small size tubing and absence of a venous reservoir, leads to a significant reduction of hemodilution with as well as a reduction in clotting factor consumption ad triggering of SIRS (Vohra et al 2009;Ohata et al 2007;Wippermann et al 2005;Fromes et al 2002). The blood pump included in the circuit is usually a centrifugal pump.…”