Yazar "McCusker, Kevin" seçeneğine göre listele
Listeleniyor 1 - 8 / 8
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe Clinical and biomaterial evaluation of a new condensed dual-function extracorporeal circuit in reoperation for coronary artery bypass surgery(Sage Publications Ltd, 2009) Gunaydin, Serdar; McCusker, Kevin; Vijay, VenkataramanaPurpose: This prospective, randomized study compared the clinical performance of three types of circuits: a newly introduced, fully-coated, interchangeable open-closed circuit with a dual configuration (hard shell with a bypass shunt), reduced length, and reduced prime of less than 800 cc (CondEC); a completely coated circuit (EC); and a similar uncoated, open circuit with standard length and prime (CONT). Methods: 75 patients undergoing reoperation for coronary revascularization were randomly allocated into three groups (N=25): Group 1: CondEC with shortened tubing, components and an open-closed configuration of low priming volume with a centrifugal pump and a shunt which bypassed the reservoir for closed configuration; Group 2: EC with a roller pump and hard-shell reservoir; Group 3: CONT. Blood samples for CBC, inflammatory mediators [Interleukin-2 (IL-2), Complement-3a (C3a)] and flow cytometry (CD11b/CD18) were collected after induction (T1) and heparin administration (T2), 15 min after cardiopulmonary bypass (CPB) (T3), before cessation of CPB (T4), 15 min after reversal (T5), and the first postoperative day (T6). Results: Leukocyte counts demonstrated significant increases at T4, T5 in CONT but remained stable in EC and CondEC (p<0.05). Platelets were preserved better at T4, T5 in both EC and CondEC study groups (p<0.05). IL-2 and C3a levels were significantly lower at T3, T4, T5 in CondEC and T4, T5 in EC (p<0.05). Blood protein adsorption analysis demonstrated increased amount of microalbumin on CONT fibers (p<0.05). Conclusions: The CondEC is a flexible, dual-function, open/closed configuration system that was easy to use, safe and achieved better biocompatibility when compared to coated and uncoated conventional circuits. (Int J Artif Organs 2009; 32: 802-10)Öğe Clinical evaluation of minimized extracorporeal circulation in high-risk coronary revascularization: impact on air handling, inflammation, hemodilution and myocardial function(Sage Publications Ltd, 2009) Günaydın, Serdar; Sarı Tamer; McCusker, Kevin; Schonrock, Uwe; Zorlutuna, YamanObjective: We examined intraoperative microembolic signals (GME), inflammatory response, hemolysis, perioperative regional cerebral oxygen saturation (rSO(2)), myocardial protection and desorbed protein amount on oxygenator fibers in high-risk patients undergoing coronary revascularization (CABG) with minimized and conventional cardiopulmonary bypass (CPB). Methods: Over a ten-month period, 40 Euroscore 6+ patients undergoing CABG were prospectively randomized to one of the two perfusion protocols (N=20): Group 1: minimized extracorporeal circuits (Mini-CPB) (ROCsafe MPC, Terumo, Ann Arbor, MI, USA) and Group 2: conventional extracorporeal circuits (CECC) (Capiox SX18, Terumo, USA). Serum creatinine kinase-MB (CKMB), free hemoglobin, interleukin-6 (IL-6) and C3a levels were measured. Blood samples were collected at T1: following induction of anesthesia; T2: thromboelastography control; T3: 15 min after commencement of CPB; T4: before cessation of CPB; T5: 15 min after protamine reversal and T6: ICU. Results: Serum IL-6 levels were significantly lower in the Mini-CPB group at T4 and T5 and C3a levels were significantly less in the Mini-CPB group at T3, T4 and T5 vs. CECC (p < 0.01). CKMB levels in coronary sinus blood demonstrated well preserved myocardium in the Mini-CPB group. Percentage expression of neutrophil CD11b/CD18 levels were significantly lower in the Mini-CPB group at T4 and T5 (p < 0.05). There were no significant differences in air handling characteristics or free plasma hemoglobin levels in either circuit. rSO(2) measurements were significantly better at T3 and T4 in the Mini-CPB vs. CECC (p < 0.05) and always higher in the Mini-CPB during follow-up. Blood protein adsorption analysis of oxygenator membranes demonstrated a significantly increased amount of microalbumin on CECC fibers (p < 0.05). Conclusion: Mini-CPB provided a comfort and safety level similar to conventional control via satisfactory air handling, attenuated inflammatory response and hemodilution, with a better clinical outcome in patients undergoing high-risk CABG.Öğe Clinical impact and biomaterial evaluation of autologous platelet gel in cardiac surgery(2008) Gunaydın, Serdar; McCusker, Kevin; SarıT.; Onur, Mehmet Ali; Gürpınar, A.; Sevim, Handan; Zorlutuna, Y.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). © 2008 SAGE Publications.Öğe Clinical performance and biocompatibility of hyaluronan-based heparin-bonded extracorporeal circuits in different risk cohorts(Oxford Univ Press, 2010) Gunaydin, Serdar; McCusker, Kevin; Sari, Tamer; Onur, Mehmet Ali; Zorlutuna, YamanThis prospective randomized study compares novel hyaluronan-based heparin-bonded circuits vs. uncoated controls across EuroSCORE patient risk strata including biomaterial evaluation. Over a two-year period, 90 patients undergoing coronary artery bypass grafting were prospectively randomized to one of the two perfusion protocols: Group 1 was treated with hyaluronan-based heparin-bonded preconnected circuits (Vision HFO-GBS (TM), Gish, CA, USA) and Group 2 with identical uncoated controls. Each group was composed of three subgroups (n = 15) with respect to preoperative evaluation of low (EuroSCORE 0-2), medium (3-5) and high (6+) risk patients. Blood samples were collected after induction (T1) and heparinization (T2), 15 min after cardiopulmonary bypass start (T3), before cessation of CPB (T4), 15 min after reversal (T5), and the first postoperative day (T6). In high-risk patients, platelet counts demonstrated significant preservation at T4, T5 and leukocyte counts were lower at T5 in hyaluronan group (P <= 0.05 vs. control). C3a (ng.ml(-1)) levels were significantly lower at T3 (0.2 +/- 0.04 vs. 0.31 +/- 0.05), T4 (0.25 +/- 0.04 vs. 0.51 +/- 0.05), T5 (0.38 +/- 0.04 vs. 0.56 +/- 0.05) and interleukin-6 (pg.ml(-1)) at T4 (91 +/- 18 vs. 124 +/- 20), T5 (110 +/- 20 vs. 220 +/- 25) in coated group vs. control (P <= 0.05). Protein desorption (microalbumin) on fibers (mg.mm(-3)) was less in hyaluronan vs. control groups (P <= 0.05). Hyaluronan coating reduced platelet adhesion and cell adsorption, and modulated inflammatory response in high-risk patients. (c) 2010 Published by European Association for Cardio-Thoracic Surgery. All rights reserved.Öğe Comparison of polymethoxyethylacrylate-coated circuits with leukocyte filtration and reduced heparinization protocol on heparin-bonded circuits in different risk cohorts(Sage Publications Ltd, 2006) Günaydin, Serdar; McCusker, Kevin; Vijay, Venkataramana; İşbir, Selim; Sari, Tamer; Onur, Mehmet Ali; Zorlutuna, YamanObjectives: The relative benefits of strategic leukofiltration on polymer-coated and low-dose heparin protocol on heparin-coated circuits were studied across EuroSCORE patient risk strata for three different cohorts. Methods: In a prospective, randomized study, 270 patients undergoing coronary artery bypass grafting were allocated into three groups (n = 90): Group 1 - polymethoxyethylacrylate-coated circuits + leukocyte filters; Group 2 - polypeptide-based heparin-bonded circuits with reduced heparinization; and Group 3 - Control: uncoated circuits. Each group was further divided into three subgroups (n = 30), with respect to low- (EuroSCORE 0-2), medium- (3-5), and high- (6+) risk patients. Blood samples were collected at T1: following induction of anesthesia; T2: following heparin administration; T3: 15 min after CPB; T4: before cessation of CPB; T5: 15 min after protamine reversal; and T6: ICU. Results: In high-risk cohorts, leukocyte counts demonstrated significant differences at T4 and T5 in Group 1, and at T4 in Group 2. Platelet counts were preserved significantly better at T4 and T5 in both groups (p < 0.05 versus control). Serum IL-2 and C3a levels were significantly lower at T3, T4 and T5 in Group 1, and T4 and T5 in Group 2 (p < 0.05). Postoperative bleeding, respiratory support time and incidence of atrial fibrillation were lower in the study groups versus control. Cell counts on filter mesh and heparin-coated fibers/ circuits were significantly higher in the high-risk cohorts versus uncoated fibers. Phagocytic capacity increased on filter mesh, especially in high-risk specimens. SEM evaluation demonstrated better preserved coated circuits. Conclusion: Leukofiltration and coating reduced platelet adhesion, protein adsorption, atrial fibrillation and reduced heparinization acted via modulation of systemic inflammatory response in high-risk groups.Öğe Influence of hematocrit and pump prime on cerebral oxygen saturation in on-pump coronary revascularization(Sage Publications Ltd, 2006) McCusker, Kevin; Chalafant, Anthony; Foe, Gordon de; Günaydın, Serdar; Vijay, VenkataramanaBackground: The couplings between cerebral oxygenation (rSO(2)), on-pump hematocrit and circuit prime are explored in this study. Methods: Thirty-eight consecutive patients undergoing coronary revascularization with cardiopulmonary bypass (CPB) were matched on preoperative hematocrit < 40% and > 40% (n = 16). Similarly, six blood prime patients were matched with six crystalloid prime patients. Hematocrit and rSO(2) levels were then compared on CPB. Results: The preoperative hematocrit > 40% group retained higher levels on pump run (p < 0.01) and significantly higher rSO(2) prior to CPB (64.8 +/- 9.6 versus 73.2 +/- 7.3), and on and off CPB (61.1 +/- 8.8 versus 67.4 +/- 6.4). Blood priming increased absolute rSO(2) (2.3 +/- 6.3 versus -10.9 +/- 5.9) and % rSO(2) (4.7 +/- 11.8 versus -14.2 +/- 7.4%) in the low hematocrit group. Conclusion: Blood primes are instrumental in high-risk and low preoperative hematocrit patients in preventing cerebral oxygen desaturation during initiation and maintenance of CPB.Öğe Perioperative blood conservation strategies in pediatric patients undergoing open-heart surgery: impact of non-autologous blood transfusion and surface-coated extracorporeal circuits(Sage Publications Ltd, 2011) Gunaydin, Serdar; McCusker, Kevin; Vijay, VenkatramanaBackground: The aim of this study was to explore the relative clinical and biomaterial effects of blood transfusions (Tx) and novel low-prime, surface-coated circuitry on perioperative outcome in a pediatric population undergoing cardiac surgery with cardiopulmonary bypass (CPB). Methods: Over a 12-month period, 80 patients weighing > 10 kg undergoing ventricular septal defect (VSD) repair with CPB were prospectively randomized into two groups according to the type of CBP circuit used, then each randomized group was enrolled into two groups again, according to the need for transfusion (N=20): Group 1-Tx-free procedures on low-prime, surface-coated extracorporeal circuitry (FX05, Terumo); Group 2-procedures requiring Tx on coated circuitry; Group 3-Tx-free procedures with standard uncoated circuitry (D902, Sorin); Group 4 (Control)-procedures requiring Tx on uncoated circuitry. Blood samples were collected at baseline (T1), at the end of the CPB (T2) and 24 h (T3) postoperatively. rSO(2) desaturation risk score > 6000 (Invos, Somanetics) was calculated by multiplying rSO(2) < 50% by time. Results: IL-6 levels (pg/ml) were significantly lower in Groups 1 and 3 versus control at T2 (13 +/- 4; 17 +/- 5 versus 33 +/- 8; p < 0.05). CD11b/CD18 levels (%) were significantly lower in Group 1 (12 +/- 4) versus control (25 +/- 8) at T2 (p < 0.05). Respiratory support time (h) was significantly less in Group 1 (11.4 +/- 6) versus control (19.8 +/- 7) (p < 0.05). rSO(2) desaturation risk > 6000 (%) was 15.7 +/- 9 in Group 1 and 26.8 +/- 11 in control (p < 0.05). Conclusion: Allogenic Tx amplifies the CPB-related inflammatory response. It is feasible to do congenital procedures safely without Tx for patients weighing > 10 kg by using combined blood management strategies.Öğe Strategic leukofiltration in cardiac surgery(2005) Günaydın, Serdar; McCusker, Kevin; Vijay, V.Systemic inflammatory response syndrome (SIRS) with activation of molecular cascades, cell activation, accumulation of interstitial fluid, organ dysfunction and, occasionally, organ failure is still a commonly recognized consequence of cardiac surgery. SIRS leads to costly complications and several strategies intended to ameliorate the symptoms that have been studied, including leukocyte reduction, using filtration. Although, the body of work suggests that leukoreduction attenuates SIRS, discrepancies remain within the literature. The recent literature is reviewed highlighting the areas where concordance is lacking. In our study, on the basis of indirect indicators of SIRS, platelet function by thromboelastography biomaterial evaluation by light and scanning electron microscopy, we present our conclusions regarding clinical outcomes and the role of leukofiltration. © 2005 Bentham Science Publishers Ltd.
