Perfusion

The minimized extracorporeal circulation system (MECC) is being used to reduce priming volume and blood/polymer contact during cardiac procedures. In this study, we evaluated the efficacy and potential advantages of the system in coronary artery bypass graft (CABG) patients. We included two groups of patients destined for CABG in a prospective, randomized study: Group A was operated on the usual pump (n = 30) while Group B was operated using the MECC (n = 50). Pre-operative demographics, intra-operative times and values as well as a series of post-operative outcome data (blood loss, transfusion requirements, ventilation time, ICU and hospital stay) were recorded. CK, CK-MB, troponin-T, IL-6 and IL-8 were measured. Pre-operative and post-operative lung function were assessed. In the MECC-operated group, patients developed less post-operative troponin-T (0.2 ± 0.3 vs. 0.5 ± 0.5 ng/mL, p=0.031) and less IL-8 (13.8 ± 5 vs. 22.5 ± 0.5 µg/L, p = 0.05). While blood loss was comparable in both groups, packed red blood cells and fresh frozen plasma were given less frequently in the MECC group (p = 0.015 resp. 0.022). The one-tailed Student’s t-test revealed shorter bypass time in the MECC group (74 ± 17 vs. 82 ± 24 min). There was no difference in ventilation and ICU-time (patients were not treated in a fast-track fashion). The FEV1 was better in the MECC group (relative values: 70.1 ± 18.2% vs. 61.1 ± 12.3%, p = 0.02). Utilization of the MECC may cause less cytokine (IL-8) liberation, owing to less blood/tubing contact, as well as less red blood cell and fresh frozen plasma demand. It may also be the circuit in patients with chronic obstructive pulmonary disease (COPD).

A 58-year-old male patient was posted for double valve replacement under hypothermic cardiopulmonary bypass (CPB). During aortic cross-clamp (AXC), the central venous pressure (CVP) was found to have increased to 22 mmHg. After 4 minutes of sustained increase in CVP, burst suppression (SR) started increasing. After 5 min of increase in SR, bispectral index (BIS) declined rapidly to 17. Propofol infusion was stopped and re-evaluation of signs of facial congestion showed changes to that effect. The perfusionist noted steadily decreasing venous return. As soon as the superior vena cava (SVC) cannula was withdrawn by 3 cm, CVP immediately declined to 6 mmHg. The venous return in the CPB reservoir normalized and BIS returned to 42 after a transient rise to a maximum of 58 and SR decreased to 0 within 2 min of repositioning of the venous cannula. The patient was successfully extubated after 7 hours without any sequelae.

Cardiotomy suction has been associated with adverse outcomes under routine conditions in patients undergoing cardiac surgery with cardiopulmonary bypass (CPB). We hypothesized that the routine use of a cell saver (CS) in place of the cardiotomy sucker would have no negative impact on transfusion rate (TR), chest tube drainage (CTD), ventilation time (VT) or intensive care unit length of stay (ICULOS) while avoiding the detrimental effects of cardiotomy suction. Retrospective data were collected from 69 patients where a cell saver was not used (NCS). Prospective data were collected from 219 patients who were followed after the implementation of an intra-operative cell saver. No significant increase in transfusion rate, chest tube drainage or ventilation time was found between the NCS group and the CS group. However, post-operative hemoglobin concentrations were significantly higher in the CS group (0.0001) and the CS group spent significantly less time in the ICU (p=0.018).

The glycocalyx covering the endothelium is shed during ischemia and reperfusion. The shedding is accompanied by increased levels of the glycocalyx component syndecan-1 in the circulation. Our aim was to compare plasma levels of syndecan-1 in patients undergoing coronary artery bypass grafting (CABG), with or without the use of cardiopulmonary bypass (CPB). Syndecan-1 plasma concentrations were measured in patients undergoing CABG on-pump (n = 22) or off-pump (n = 22). The syndecan-1 concentration increased significantly from 29.5 ± 4.6 ng/mL at baseline to 98.7 ± 9.8 ng/mL (p < 0.01) after the start of CPB or 30 minutes after the induction of anesthesia in the off-pump group. There were no significant differences in peak syndecan-1 plasma concentrations between on-pump and off-pump patients. Plasma levels of syndecan-1 increased significantly during CABG, with or without the use of CPB. There were no significant differences in syndecan-1 concentrations in the two groups.

The cytokine network and its association with complement activation during cardiac surgery with cardiopulmonary bypass (CPB) is complex. Extracorporeal membrane oxygenation (ECMO) differs from CPB in duration of days to weeks rather than hours. However, few studies have analyzed the levels of inflammatory mediators during ECMO treatment. Plasma samples from 22 patients [nine neonates, one infant, four children and eight adults (14 males and eight female)] who underwent ECMO treatment were collected prior to, during and after treatment, and analyzed for concentrations of inflammatory and anti-inflammatory cytokines and parameters of complement activation. Seven children were treated for cardiac and seven for pulmonary failure and, in the adult group, four were treated for cardiac and four for pulmonary failure. ECMO was performed with veno-arterial (VA) bypass in all children and five adults, and with veno-venous (VV) bypass in three adults. Fourteen patients survived (64%) and eight (36%) patients died during follow-up. A marked (~99%) and rapid (i.e., within two days) decrease in IL-6 was seen in survivors. The non-survivors were characterized by persistently high IL-6 levels throughout the observation period (i.e., until death). C-reactive protein (CRP) levels showed a similar pattern as the IL-6, with higher levels in non-survivors throughout the observation period. However, in contrast to IL-6, the differences between survivors and non-survivors reached statistical significance, but only at the end of the observation period. It is possible that early measurements of IL-6 in ECMO patients could give prognostic information beyond that of CRP.

We compared the clinical efficacy of autologous platelet gel (APG) and gelatine (CONT), including biomaterial evaluation. In a prospective, randomized, controlled trial, 64 patients undergoing complex coronary artery bypass graft (CABG) surgery and/or aortic surgery, in whom the surgeon was able to identify a bleeding site for which conventional means to stop bleeding were impractical or proved unsuccessful, were enrolled. Aortic punch biopsy from each patient was harvested in explant cell (EC) culture media. Hemostasis success for the “oozing” category was 89% in APG and 60% in CONT (p< 0.05). For the “heavy bleeding” category, the success rates were 92% in APG and 45% in CONT (p<0.01). Contact of gelatine inhibited EC proliferation and APG increased cell cycling and EC quantity. Phagocytic capacity (PC) was significantly higher in the APG group (p<0.001). APG was significantly better than CONT with respect to hemostatic success rate, effects on wound healing and increased resistance to infection (PC).

Erythropoietin (EPO) exerts a tissue-protective activity in several non-haematopoietic tissues such as heart, brain, spinal cord and muscle. We evaluated the relationship between pre-operative endogenous EPO blood levels and myocardial damage in patients undergoing cardiopulmonary bypass (CPB). Furthermore, we investigated whether pre-operative administration of a single bolus of 40,000 IU epoetin alpha (EPOα) would reduce troponin I or creatine kinase isoenzyme (CK-MB) after on-pump coronary artery bypass graft (CABG) surgery. Sixty-seven patients (45 CABG, 22 valvular surgery) were enrolled. EPO was measured in the pre-surgical period and correlated to post-surgical troponin I and CK-MB peaks. Subsequently, forty patients scheduled for CABG were randomized into two groups, receiving, respectively, a) standard medical and surgical treatment (20 patients) and b) the same treatment plus 40,000 IU of EPOα in a single bolus injection in the immediate pre-surgical period (20 patients). In our population, we did not find any correlation between pre-surgical EPO and post-surgical troponin I or CK-MB peaks (p Pearson > 0.05). Furthermore, patients treated with EPOα did not show differences compared to the control group in either troponin I (1.7±1.8 vs 2.6±3.4, p>0.05) or CK-MB (19.6 ±13.2 vs 17.1±12.6, p>0.05) peaks measured in the post-surgical period.

This case report describes the successful treatment of severe accidental hypothermia of a 40-year-old woman. At arrival in the operating theatre her rectal temperature was 23°C, her nasal temperature 21°C and her periferal temperature 14°C. The patient presented with a severe respiratory and metabolic acidosis which was corrected during cardiopulmonary bypass (CPB). She was rewarmed to obtain a rectal and nasal temperature of 34°C. After 272 minutes, the patient was weaned successfully from CPB. The patient remained at mild hypothermia (34°C) for 24 hours in the intensive care unit (ICU). The chest X-ray showed some signs of acute respiratory distress syndrome (ARDS) in spite of normal blood gas values. This improved within a few days and, after five days, she was transferred to the nursing department. On the seventh day, the patient was discharged from hospital without physical or neurological complaints.