Can leucocyte depletion reduce reperfusion injury following cardiopulmonary bypass?

Abstract

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was 'Can leucocyte depletion (LD) reduce reperfusion injury following cardiopulmonary bypass?'. Altogether more than 74 papers were found using the reported search, of which nine represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. We conclude that there appears to be little or no clinical benefit gained from the use of LD treatment. The majority of studies, looking at outcomes including the duration of hospital and intensive care unit (ICU) stay, intubation time, inotropic support required and postoperative arrhythmias, found the results comparable between patients receiving LD treatment and controls. Biochemical parameters of reperfusion inflammation and cardiac damage are reduced in many studies, suggesting an attenuation of reperfusion injury at a cellular level, but this does not appear to be transferable to clinical improvement. However, one study using patients with severely low left ventricular ejection fractions (LVEF), found those receiving LD treatment required less inotropic support and experienced a significant increase in LVEF postoperatively when compared with controls, indicating that the benefit of LD may depend on preoperative status and susceptibility to reperfusion damage. In conclusion, LD should not be used routinely in cardiac surgery.

Long-Term Leukocyte Filtration Should Be Avoided during Extracorporeal Circulation

“…Short-term use of a leukocyte filter reduced circulating leukocytes; with continued usage, leukocytes that adhered to the filter membrane disrupted, leading to leakage of protease, inflammatory reaction, and tissue destruction. Our results may explain why leukocyte depletion could not improve the outcomes in some clinical studies [12–14]. …”

“…Some studies have suggested that leukocyte filters could reduce expression of CD11b/CD18 in leukocytes [6], alleviate systemic inflammatory responses [7, 8], and improve outcomes [7, 9, 10]. However, other studies have shown that leukocyte filters cannot reduce [11], and may even increase, the release of inflammatory cytokines and proteases, and thus could have a negative effect [12–14]. …”

Systemic inflammatory response syndrome is reduced by preoperative plasma-thrombo-leukocyte aphaeresis in a pig model of cardiopulmonary bypass

“…another study showed that leukocyte removal by filters is suitable and safe for use during cardiac surgery. early clinical reports appeared to confirm these findings, but reviews in recent years have concluded that the clinical effects have not been evaluated vigorously enough and that no recommendations can be made regarding the use of leukocyte-depleting filters in routine cardiac surgery 8 . The aim of this experimental study was to prevent sirs by reducing all blood components of the host protection system (plasma protein systems, leukocytes and thrombocytes) by using pre-operative aphaeretic-filtration in a pig model of sirs elicited by cpB, with 4 days of postoperative observation.…”

Investigation of the Oxidative Stress, the Altered Function of Platelets and Neutrophils, in thePatients with Peripheral Arterial Disease

“…There are pharmacologic tools, and protective processes, which can reduce IR injury. Antioxidants, such as N-acetylcysteine, vitamin E, mannitol, thiols, alkaloids and endogenous antioxidants, such as superoxide dismutase, reduced glutathion, glutathione reductase, catalase, or ion chelators functions due to inactivation of free radicals, which are key element in IR induced tissue damages (Arato et al 2010), (Peto K, et al 2007 ), but leukocyte depletion, anti-cytokine or leukocyte adhesion molecule monoclonal antibody therapies ended with conflicting results (Arato et al 2010) (Loberg AG et al ,2011). Among other effective possibilities, ischemic postconditioning is one of the most effective processes in reducing IR caused damages, which was first introduced by Vinten-Johansen's group in 2003.…”