Comparison of inflammatory responses after off-pump and on-pump coronary surgery using surface modifying additives circuit

Impact of extracorporeal haemoadsorption during prolonged cardiopulmonary bypass on the incidence of acute kidney injury

The usage of cardiopulmonary bypass (CPB) in cardiothoracic surgery contributes to the activation of the inflammatory response. In certain cases, the systemic inflammatory response may be immoderate, leading to organ dysfunction, such as acute renal failure or multiorgan dysfunction. This study aimed to examine the effect of haemoadsorption (HA) therapy on inflammatory markers and renal damage indices during cardiopulmonary bypass and in the early postoperative period. We conducted a retrospective analysis of prospectively collected data in a single tertiary care center on patients operated between January 2021 and May 2022. The levels of inflammatory markers and renal parameters in blood samples (Interleukin (IL) 6, C-reactive protein (CRP), white blood cells, lactate, procalcitonin (PCT), and NT-proBNP, urea, creatinine, glomerular filtration rate (GFR), mechanical ventilation days and intensive care unit (ICU) days) were compared between the three groups. Data from the Jafron HA 330 (n = 20) and CytoSorb300 (n = 20) groups were compared with those from the control group (n = 20). All patients underwent cardiopulmonary bypass for more than 120 min. Baseline patient characteristics were similar in all three groups. Acute kidney injury (AKI) was diagnosed in 17 patients (28.3%); seven patients were in the Jafron HA 330, two in the CytoSorb300, and eight in the control group. We found that IL1α, IL 6, IL8, Lactate dehydrogenase, PCT, NT-proBNP, CRP, Leukocyte, and TNFα had no significant or clinical difference between the CytoSorb 300 and Jafron HA 330 adsorber groups. Our results indicate that haemoadsorption therapy does not significantly reduce the risk of AKI after prolonged CPB, but decreases the need for renal replacement therapy.

Extracorporeal Hemadsorption versus Glucocorticoids during Cardiopulmonary Bypass: A Prospective, Randomized, Controlled Trial

Extracorporeal hemadsorption may reduce inflammatory reaction in cardiopulmonary bypass (CPB) surgery. Glucocorticoids have been used during open-heart surgery for alleviation of systemic inflammation after CPB. We compared intraoperative hemadsorption and methylprednisolone, with usual care, during complex cardiac surgery on CPB, for inflammatory responses, hemodynamics, and perioperative course. Seventy-six patients with prolonged CPB were recruited and randomized, with 60 included in final analysis. Allocation was into three groups: Methylprednisolone (n = 20), Cytosorb (n = 20), and Control group (usual care, n = 20). Proinflammatory (TNF-α, IL-1β, IL-6, and IL-8) and anti-inflammatory (IL-10) cytokines which complement C5a, CD64, and CD163 expression by immune cells were analyzed within the first five postoperative days, in addition to hemodynamic and clinical outcome parameters. Methylprednisolone group, compared to Cytosorb and Control had significantly lower levels of TNF-α (until the end of surgery, p < 0.001), IL-6 (until 48 h after surgery, p < 0.001), and IL-8 (until 24 h after surgery, p < 0.016). CD64 expression on monocytes was the highest in the Cytosorb group and lasted until the 5^th postoperative day (p < 0.016). IL-10 concentration (until the end of surgery) and CD163 expression on monocytes (until 48 h after surgery) were the highest in the Methylprednisolone group (p < 0.016, for all measurements between three groups). No differences between groups in the cardiac index or clinical outcome parameters were found. Methylprednisolone more effectively ameliorates inflammatory responses after CPB surgery compared to hemadsorption and usual care. Hemadsorption compared with usual care causes higher prolonged expression of CD64 on monocytes but short lasting expression of CD163 on granulocytes. Hemadsorption with CytoSorb® was safe and well tolerated. This trial is registered with clinicaltrials.gov (NCT02666703).

Effects of Alprazolam and Melatonin Used for Premedication on Oxidative Stress, Glicocalyx Integrity and Neurocognitive Functions

Objective

The purpose of this investigation was to compare the effect of alprazolam and melatonin on oxidative stress, glicocalyx integrity and neurocognitive function in patients undergoing coronary artery bypass grafting (CABG).

Methods

Overall, 42 patients undergoing CABG were retrospectively included in this study. Blood samples which preserved at -70°C for a previous study were used for this study. The participants were divided into two groups. Patients in the Group A were administered alprazolam before the operation, whereas melatonin was used for premedication in the Group M. Blood samples were collected at three time points [T0: before anaesthesia induction, T1: admittance to intensive care unit (ICU), T2: 24 h after ICU admission], and oxidative stress parameters and glicocalyx integrity were evaluated. Furthermore, Mini-Mental State Examination was recorded to measure neurocognitive function.

Results

The total thiol levels which were measured as an antioxidant parameter were significantly higher, and free Hb values were significantly lower in the Group M compared to the Group A (p<0.05). No significant differences were found in order to oxidative stress parameter levels, extubation time, length of hospital stay, durations of cross-clamp, cardiopulmonary bypass and operation and Mini-Mental State Examination results between the two groups (p>0.05).

Conclusion

In light of positive effects on oxidatif stress parameters, melatonin may be considered as a good and safe premedication agent with its anxiolytic, antioxidant and minimal haemodynamic and respiratory effects.

Influence of the type of congenital heart defects on epithelial lining fluid composition in infants undergoing cardiac surgery with cardiopulmonary bypass

BackgroundIn children with congenital heart disease (CHD), altered pulmonary circulation compromises gas exchange. Moreover, pulmonary dysfunction is a complication of cardiac surgery with cardiopulmonary bypass (CPB). No data are available on the effect of different CHDs on lung injury. The aim of this study was to analyze epithelial lining fluid (ELF) surfactant composition in children with CHD.MethodsTracheal aspirates (TAs) from 72 CHD children (age 2.9 (0.4-5.7) months) were obtained before and after CPB. We measured ELF phospholipids, surfactant proteins A and B (SP-A, SP-B), albumin, and myeloperoxidase activity. TAs from 12 infants (age 1.0 (0.9-2.9) months) with normal heart/lung served as controls.ResultsHeart defects were transposition of great arteries (19), tetralogy of Fallot (TOF, 20), atrial/ventricular septal defect (ASD/VSD, 22), and hypoplastic left heart syndrome (11). Increased levels of ELF SP-B were found in all defects, increased myeloperoxidase activity in all except the TOF, and increased levels of ELF albumin and SP-A only in ASD/VSD patients. Postoperatively, ELF findings remained unchanged except for a further increase in myeloperoxidase activity.ConclusionELF composition has distinctive patterns in different CHD. We speculate that a better knowledge of the ELF biochemical changes may help to prevent respiratory complications.

Meta-analysis of interleukin 6, 8, and 10 between off-pump and on-pump coronary artery bypass groups

This study aimed to evaluate the role of off-pump coronary artery bypass (CAB) surgery on the decrease of postoperative inflammatory responses in patients. We systematically searched databases of PubMed and Embase to select the related studies. Interleukin (IL) 6, 8, and 10 were used as outcomes and pooled analysis was performed using R 3.12 software. Standardized mean differences (SMDs) and their 95% confidence intervals (95% CIs) were considered as effect estimates. A total of 27 studies, including 1340 participants, were recruited in this meta-analysis. The pooled analyses showed that postoperative concentration of IL-10 at 12 hours was significantly lower in off-pump CAB group compared to on-pump CAB group (SMD = -1.3640, 95% CI = -2.0086--0.7193). However, no significant differences were found in pre and postoperative concentrations of IL-6 and 8 between off-pump and on-pump CAB groups. These results suggest that there is no advantage of off-pump CAB surgery in the reduction of inflammation compared to on-pump CAB surgery.

Inflammation and Oxidative Stress in Cardiac Surgery Patients Treated to Intensive Versus Conservative Glucose Targets

OBJECTIVE

We aimed to determine (a) longitudinal changes of inflammatory and oxidative stress markers and (b) the association between markers of inflammation and perioperative complications in coronary artery bypass surgery (CABG) patients treated with intensive vs conservative blood glucose (BG) control.

METHODS

Patients with diabetes (n = 152) and without diabetes with hyperglycemia (n = 150) were randomized to intensive (n = 151; BG: 100-140 mg/dL) or to conservative (n = 151; BG: 141-180 mg/dL) glycemic targets. Plasma cortisol, high-sensitivity C-reactive protein (hsCRP), tumor necrosis factor-α, interleukin-6 (IL-6), thiobarbituric acid-reactive substances, and 2'-7'-dichlorofluorescein were measured prior to and at days 3, 5, and 30 after surgery.

RESULTS

Intensive glycemic control resulted in lower mean BG (132 ± 14 mg/dL vs 154 ± 17 mg/dL, P < 0.001) in the intensive care unit. Plasma cortisol and inflammatory markers increased significantly from baseline after the third and fifth day of surgery (P < 0.001), and returned to baseline levels at 1 month of follow-up. Patients with perioperative complications had higher levels of cortisol, hsCRP, IL-6, and oxidative stress markers compared with those without complications. There were no significant differences in inflammatory and oxidative stress markers between patients, with or without diabetes or complications, treated with intensive or conventional glucose targets.

CONCLUSION

We report no significant differences in circulating markers of acute inflammatory and oxidative stress response in cardiac surgery patients, with or without diabetes, treated with intensive (100-140 mg/dL) or conservative (141-180 mg/dL) insulin regimens.

Comparison of Two Miniaturized Cardiopulmonary Bypass Systems Regarding Inflammatory Response

Cardiopulmonary bypass (CPB) is a known mediator of systemic inflammatory response. Extracorporeal circulations are undergoing continuous modifications and optimizations to achieve better results. Hence we aim to compare the inflammatory response associated with two recent miniature extracorporeal circulation systems during normothermic CPB. We measured plasma levels of cytokines including interleukin (IL)-1β, IL-6, IL-10, tumor necrosis factor-α, migration inhibitory factor (MIF), receptor for advanced glycation endproduct, and cluster of differentiation 40 ligand in 60 consecutive patients during the first 24 h after CPB. The patients were prospectively randomized to one of three trial groups: patients in group A were operated with the minimal extracorporeal circulation circuit (MECC, Maquet, Rastatt, Germany), group B operated with the extracorporeal circulation circuit optimized (ECC.O, Sorin, Italy), and group C operated with a conventional extracorporeal circuit (CECC, Maquet). Arterial blood samples were collected at intervals before, 30 min after initiation, and after termination of CPB. Further samples were collected 6 and 24 h after CPB. IL-10 levels were significantly raised in the CECC group as compared with either of the mini ECC-circuits with a peak concentration at 6 h postoperatively. Human MIF concentrations were significantly higher in the CECC group starting 30 min after CPB and peaking at the end of CPB. The overall reduction in cytokine concentrations in the mini-ECC groups correlated with a lower need for blood transfusion in MECC and a shorter mechanical ventilation time for ECC.O. Normothermic CPB using minimally invasive extracorporeal circulation circuits can reduce the inflammatory response as measured by cytokine levels, which may be beneficial for perioperative preservation of pulmonary function and hemostasis in low risk patients.

ISMICS Consensus Conference and Statements of Randomized Controlled Trials of Off-Pump versus Conventional Coronary Artery Bypass Surgery

Objective

At this consensus conference, we developed evidence-informed consensus statements and recommendations on the practice of off-pump coronary artery bypass graft (OPCAB) by systematically reviewing and performing meta-analysis of the randomized controlled trials (RCTs) comparing OPCAB and conventional coronary artery bypass (CCAB).

Methods

All RCTs of OPCAB versus CCAB through April 2013 were screened, and 102 relevant RCTs (19,101 patients) were included in a systematic review and meta-analysis (15 RCTs of 9551 high-risk patients; and 87 RCTs of 9550 low-risk patients) in accordance with the Cochrane Collaboration and PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) methodology. Consensus statements for the risks and benefits of OPCAB surgery in mortality, morbidity, and resource use were developed based on best available evidence.

Results

Compared to CCAB, it is reasonable to perform OPCAB to reduce risks of stroke [class IIa, level of evidence (LOE) A], renal dysfunction/failure (class IIa, LOE A), blood transfusion (class I, LOE A), respiratory failure (class I, LOE A), atrial fibrillation (class I, LOE A), wound infection (class I, LOE A), ventilation time, and ICU and hospital length of stay (class I, LOE A). However, OPCAB may be associated with a reduced number of grafts performed (class I, LOE A) and with diminished graft patency (class IIa, LOE A, with increased coronary reintervention at 1 year and beyond (class IIa, LOE A), as well as increased mortality at a median follow-up of 5 years (class IIb, LOE A).

Conclusions

OPCAB compared with CCAB may improve outcomes in the short-term (stroke, renal dysfunction, blood transfusion, respiratory failure, atrial fibrillation, wound infection, ventilation time, and length of stay). However, over the longer-term, OPCAB may be associated with reduced graft patency, and increased risk of cardiac re-intervention and death.

Biomarkers of lung injury in cardiothoracic surgery

Diagnosis of pulmonary dysfunction is currently almost entirely based on a vast series of physiological changes, but comprehensive research is focused on determining biomarkers for early diagnosis of pulmonary dysfunction. Here we discuss the use of biomarkers of lung injury in cardiothoracic surgery and their ability to detect subtle pulmonary dysfunction in the perioperative period. Degranulation products of neutrophils are often used as biomarker since they have detrimental effects on the pulmonary tissue by themselves. However, these substances are not lung specific. Lung epithelium specific proteins offer more specificity and slowly find their way into clinical studies.

The utility of lung epithelium specific biomarkers in cardiac surgery: a comparison of biomarker profiles in on- and off-pump coronary bypass surgery

Background

Despite continuous improvements in materials and perfusion techniques, cardiac surgery still causes lung injury and a delay of pulmonary recovery. Currently, there is no gold standard for quantifying cardiac surgery induced lung injury and dysfunction. Adding objective measures, such as plasma biomarkers, could be of great use here. In this study the utility of lung epithelium specific proteins as biomarkers for lung dysfunction was evaluated.

Methods

Serial measurements of plasma concentrations of Clara cell 16 kD (CC16) protein, Surfactant protein D (SP-D), Elastase and Myeloperoxidase were performed on blood samples from 40 patients who underwent coronary artery bypass grafting with cardiopulmonary bypass (CABG, n = 20) or without cardiopulmonary bypass (OPCAB, n = 20).

Results

The increase of SP-D and CC16 between pre-operative concentrations and concentrations at the end of cardiopulmonary bypass, correlated with the Aa-O₂ gradient at 1 hour on the ICU (R_s = 0.409, p = .016 and R_s = 0.343, p = .043, respectively).

Furthermore, SP-D and CC16 were higher in CABG than in OPCAB at the end of surgery [8.96 vs. 4.91 ng/mL, p = .042 and 92 vs. 113%, p = .007, respectively]. After 24 h both biomarkers returned to their baseline values.

Conclusions

Our results show that increases in plasma of SP-D and CC16 correlate with clinical lung injury after coronary artery bypass surgery. Therefore, lung epithelium specific proteins seem to be a useful biomarker for measuring lung injury in the setting of cardiac surgery.

Off-pump versus on-pump coronary artery bypass grafting for ischaemic heart disease

BACKGROUND

Coronary artery bypass grafting (CABG) is performed both without and with cardiopulmonary bypass, referred to as off-pump and on-pump CABG respectively. However, the preferable technique is unclear.

OBJECTIVES

To assess the benefits and harms of off-pump versus on-pump CABG in patients with ischaemic heart disease.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) on The Cochrane Library (Issue 1, 2011), MEDLINE (OVID, 1950 to February 2011), EMBASE (OVID, 1980 to February 2011), Science Citation Index Expanded on ISI Web of Science (1970 to February 2011) and CINAHL (EBSCOhost, 1981 to February 2011) on 2 February 2011. No language restrictions were applied.

SELECTION CRITERIA

Randomised clinical trials of off-pump versus on-pump CABG irrespective of language, publication status and blinding were selected for inclusion.

DATA COLLECTION AND ANALYSIS

For statistical analysis of dichotomous data risk ratio (RR) and for continuous data mean difference (MD) with 95% confidence intervals (CI) were used. Trial sequential analysis (TSA) was used for analysis to assess the risk of random error due to sparse data and to multiple updating of accumulating data.

MAIN RESULTS

Eighty-six trials (10,716 participants) were included. Ten trials (4,950 participants) were considered to be low risk of bias. Pooled analysis of all trials showed that off-pump CABG increased all-cause mortality compared with on-pump CABG (189/5,180 (3.7%) versus 160/5144 (3.1%); RR 1.24, 95% CI 1.01 to 1.53; P =.04). In the trials at low risk of bias the effect was more pronounced (154/2,485 (6.2%) versus 113/2,465 (4.6%), RR 1.35,95% CI 1.07 to 1.70; P =.01). TSA showed that the risk of random error on the result was unlikely. Off-pump CABG resulted in fewer distal anastomoses (MD -0.28; 95% CI -0.40 to -0.16, P <.00001). No significant differences in myocardial infarction, stroke, renal insufficiency, or coronary re-intervention were observed. Off-pump CABG reduced post-operative atrial fibrillation compared with on-pump CABG, however, in trials at low risk of bias, the estimated effect was not significantly different.

AUTHORS' CONCLUSIONS

Our systematic review did not demonstrate any significant benefit of off-pump compared with on-pump CABG regarding mortality, stroke, or myocardial infarction. In contrast, we observed better long-term survival in the group of patients undergoing on-pump CABG with the use of cardiopulmonary bypass and cardioplegic arrest. Based on the current evidence, on-pump CABG should continue to be the standard surgical treatment. However, off-pump CABG may be acceptable when there are contraindications for cannulation of the aorta and cardiopulmonary bypass. Further randomised clinical trials should address the optimal treatment in such patients.

Comparison of inflammatory response during on-pump and off-pump coronary artery bypass surgery

PURPOSE

On-pump coronary artery bypass graft (CABG) surgery has been traditionally associated with a higher magnitude of inflammatory response than off-pump CABG. However with the development of polymer-coated biocompatible extracorporeal circuits, we wanted to see if cardiopulmonary bypass still played an important role in triggering this inflammatory response.

METHODS

In this prospective observational study, 33 patients undergoing CABG surgeries (25 on-pump and 8 off-pump patients) were studied. Serial plasma cytokine (TNF IL-6, IL-10) and procalcitonin concentrations were measured at different time-points during and after the surgery. Demographic and baseline clinical data, intra-operative management details and post-operative complications were also collected from the patients' charts.

RESULTS

Plasma levels of all 4 mediators increased during surgery and returned towards normal postoperatively. There were no differences between groups for any mediator at any time-point.

CONCLUSIONS

We conclude that with the use of recent polymer-coated biocompatible extracorporeal circuits, the inflammatory response triggered by on-pump CABG becomes very similar in magnitude and pattern to that triggered by off-pump CABG. Thus, the surgical procedure contributes to most of the inflammatory response, with the extra-corporeal circuit having minimal to no effect on this response.

The impact of different biocompatible coated cardiopulmonary bypass circuits on inflammatory response and oxidative stress

This study was to compare the impact of different biocompatible coated circuits on inflammatory response and oxidative stress induced during cardiopulmonary bypass (CPB). Seventy-eight patients undergoing elective coronary artery bypass grafting (CABG) with CPB were randomly assigned to five groups with different biocompatible coated circuits: Trillium, Bioline, Phosphorylcholine, Polymethoxyethyl acrylate (PMEA), and the uncoated control group. Blood was drawn at three different time points: before CPB, 6 and 72 hours post CPB. Unlike the Trillium group, serum levels of TNF-α in the Bioline and Phosphorylcholine groups significantly increased only at 72 hours post CPB (p < 0.05). Serum levels of IL-6 significantly increased at 6 and 72 hours post CPB in all groups (p < 0.01). The Trillium group showed a significant increase of IL-10 compared to the control group at 72 hours post CPB (p < 0.05). Serum levels of NOx in the Phosphorylcholine group significantly decreased at 6 hours post CPB compared to baseline (p < 0.05). Both the Bioline and Phosphorylcholine groups showed statistical decreases in serum NOx levels compared with other groups at 6 hours post CPB (p < 0.05). A significant difference in NOx levels between the Bioline and the control group was also observed at 72 hours post CPB. Myeloperoxidase levels were significantly elevated at 6 and 72 hours post CPB in all groups (p < 0.05). Inflammatory response and oxidative stress are elevated during CABG with CPB. Heparin-coated and the Phosphorylcholine-coated circuits induce less inflammatory responses and oxidative stress compared to other circuits.

Release of cardiac biochemical and inflammatory markers in patients on cardiopulmonary bypass undergoing coronary artery bypass grafting

BACKGROUND

Determination of cardiac markers can assess cardiac injury induced by cardiopulmonary bypass (CPB) during coronary artery bypass grafting (CABG). However, the markers and their release pattern are not well defined. This study was aimed at assessing the release and timing of cardiac biochemical and inflammatory markers in patients undergoing elective CABG with CPB.

METHODS

Forty patients undergoing elective CABG were included in this study. Blood samples were collected for biochemical measurements at the following time points: immediately prior to the induction of anesthesia, one, six, 12, and 24 hours after initiation of CPB.

RESULTS

Increased release of cardiac troponin I was observed one hour after initiation of CPB (p < 0.05) and reached the maximum at 12 hours after CPB (p < 0.01). Serum CK-MB enzyme activity and CK-MB mass both were highly elevated starting at one hour after initiation of CPB, peaked at six hours, and remained elevated until 24 hours after CPB. Both lactate and lactate dehydrogenase were highly elevated six hours after CPB and peaked at 12 hours after CPB (p < 0.01). Serum levels of interleukin-6 and tumor necrosis factor-alpha increased significantly one hour after initiation of CPB and peaked at six hours (p < 0.01), while serum high sensitivity C-reactive protein levels started to elevate 12 hours after CPB (p < 0.01).

CONCLUSION

Monitoring of these markers could help to determine implementation of protective interventions during CABG with CPB to prevent myocardial deterioration and to predict the risk and prognosis.

Clinical outcomes in randomized trials of off- vs. on-pump coronary artery bypass surgery: systematic review with meta-analyses and trial sequential analyses

AIMS

To assess the clinical outcomes of off- vs. on-pump coronary artery bypass surgery in randomized trials.

METHODS AND RESULTS

We searched electronic databases and bibliographies until June 2007. Trials were assessed for risk of bias. Outcome measures were all-cause mortality, myocardial infarction, stroke, atrial fibrillation, and renewed coronary revascularization at maximum follow-up. We applied trial sequential analysis to estimate the strength of evidence. We found 66 randomized trials. There was no statistically significant differences regarding mortality [relative risk (RR) 0.98; 95% confidence interval (CI) 0.66-1.44], myocardial infarction (RR 0.95; 95% CI 0.65-1.37), or renewed coronary revascularization (RR 1.34; 95% CI 0.83-2.18). We found a significant reduced risk of atrial fibrillation (RR 0.69; 95% CI 0.57-0.83) and stroke (RR 0.53; 95% CI 0.31-0.91) in off-pump patients. However, when continuity correction for zero-event trials was included, the reduction in stroke became insignificant (RR 0.62; 95% CI 0.32-1.19). Trial sequential analysis demonstrated overwhelming evidence supporting that off-pump bypass surgery reduces atrial fibrillation.

CONCLUSION

Off-pump surgery reduces the risks of postoperative atrial fibrillation compared with on-pump surgery. For death, myocardial infarction, stroke, and renewed coronary revascularization, the evidence is still weak and more low-bias risk trials are needed.

Pulsatile pulmonary perfusion during cardiopulmonary bypass reduces the pulmonary inflammatory response

BACKGROUND

Pulmonary dysfunction presumably linked to an inflammatory response is frequent after cardiac operations using cardiopulmonary bypass (CPB) and pulmonary hypoperfusion. We previously demonstrated that active perfusion of the lungs during CPB reduces ischemic lung injury. We now hypothesized that avoiding ischemia of the lungs during CPB by active pulmonary perfusion would decrease pulmonary inflammatory response.

METHODS

Pigs were randomized to a control group with CPB for 120 minutes, followed by 120 minutes of postbypass reperfusion, or to the study groups where animals underwent active pulmonary perfusion with pulsatile or nonpulsatile perfusion during CPB (n = 7 in each group). Activation of transcription factor activity (nuclear factor [NF]-kappaB and activating protein [AP]-1) was determined by electrophoretic mobility shift assay. Levels of proinflammatory protein expression (interleukin [IL]-1, IL-6, and tumor necrosis factor [TNF]-alpha) were quantified by enzyme-linked immunoabsorbent assay. Caspase-3 activity was measured using a fluorogenic assay.

RESULTS

The activation of transcription factor AP-1 and NF-kappaB was reduced in the pulsatile pulmonary perfusion group. The caspase-3 activity and the expression of IL-1, IL-6, and TNF-alpha revealed a significant decrease in the pulsatile and nonpulsatile pulmonary perfusion groups. Animals of the pulsatile pulmonary perfusion group showed significantly reduced IL-6 expression and caspase-3 activity compared with the nonpulsatile pulmonary perfusion group.

CONCLUSIONS

Active pulmonary perfusion reduces the inflammatory response and apoptosis in the lungs observed during conventional CPB. This effect is greatest when pulmonary perfusion is performed with pulsatility. The reduction in cytokine expression by pulsatile pulmonary perfusion might be mediated by AP-1 and NF-kappaB.

Inflammatory response and cardioprotection during open-heart surgery: the importance of anaesthetics

Open-heart surgery triggers an inflammatory response that is largely the result of surgical trauma, cardiopulmonary bypass, and organ reperfusion injury (e.g. heart). The heart sustains injury triggered by ischaemia and reperfusion and also as a result of the effects of systemic inflammatory mediators. In addition, the heart itself is a source of inflammatory mediators and reactive oxygen species that are likely to contribute to the impairment of cardiac pump function. Formulating strategies to protect the heart during open heart surgery by attenuating reperfusion injury and systemic inflammatory response is essential to reduce morbidity. Although many anaesthetic drugs have cardioprotective actions, the diversity of the proposed mechanisms for protection (e.g. attenuating Ca(2+) overload, anti-inflammatory and antioxidant effects, pre- and post-conditioning-like protection) may have contributed to the slow adoption of anaesthetics as cardioprotective agents during open heart surgery. Clinical trials have suggested at least some cardioprotective effects of volatile anaesthetics. Whether these benefits are relevant in terms of morbidity and mortality is unclear and needs further investigation. This review describes the main mediators of myocardial injury during open heart surgery, explores available evidence of anaesthetics induced cardioprotection and addresses the efforts made to translate bench work into clinical practice.