血液稀释在小儿心内直视手术中的应用

目的：３０例小儿心内直视手术以海脉素为心肺机预充液，搪塞血液稀释对小儿血球压积、血浆总蛋白、血小板及血浆电解质的影响。方法：３０例分为三组，血液稀释组（ＨＥＤ），稀释式自身输血ＨＡＴ），输库血组（ＳＢＴ），每组１０例，观察三组麻醉前、心肺转流１５ｍｉｎ，回输机器余血１５ｍｉｎ、术后２４ｈ和７２ｈ血球压积，血浆总蛋白 、血小板及血浆电解质变化。结果：心肺转流１５ｍｉｎＨＥＤ组和ＳＢＴ组呈中度、ＨＡＴ     

Heparin influences human platelet behavior in cardiac surgery with or without cardiopulmonary bypass

The objective was to investigate whether the platelet dysfunction in cardiac surgery is caused by hemodilution or by shear stress due to cardiopulmonary bypass (CPB). Platelet count and function were prospectively analyzed in two groups of patients undergoing cardiac surgery either with or without CPB (n = 40). In the first study (n = 20; 10 patients with and 10 without CPB), platelet counts were assessed at seven time points. In the second study (n = 20; 10 patients with and 10 without CPB), platelet function was studied with platelet aggregometry at different points during surgery: (a) after induction of anesthesia; (b) after sternotomy; and (c) 1 h after heparin. In the first study, the CPB group showed a significant decrease in platelet count starting after sternotomy (230 +/- 34 vs. 182 +/- 25, P < 0.05) and a maximum decrease at day 1 postoperative (96 +/- 34, P < 0.05). A similar observation was made in the non-CBP group. In the second study, a significant decrease of ADP (54 +/- 13% vs. 38 +/- 9%, P < 0.05), AA (76 +/- 16% vs. 22 +/- 14%, P < 0.05), and Collagen (66 +/- 13% vs. 37 +/- 11%, P < 0.05) induced platelet aggregation was observed at MOMENT d compared to the beginning of surgery in the CPB group. In the non-CBP group a significant decrease was observed in AA-induced platelet aggregation at MOMENT d (83% +/- 4 vs. 44% +/- 14, P < 0.05). The reduction in platelet count is similar with or without cardiopulmonary bypass and is due to pure hemodilution. Platelet function reduces significantly after heparin administration. Hemodilution and predominantly heparin are the causes of platelet dysfunction after cardiac surgery.     

Efficacy of a new coating material, PMEA, for cardiopulmonary bypass circuits in a porcine model

BACKGROUND: A new coating material, poly-2-methoxyethyl acrylate (PMEA), was developed to improve the biocompatibility of cardiopulmonary bypass (CPB) circuits. METHODS: To investigate the efficacy of the PMEA coating for CPB circuits, we compared PMEA-coated circuits (group P, n = 6) with uncoated circuits (group C, n = 6) and heparin (covalent-bonded heparin, Hepaface)-coated circuits (group H, n = 6) in a porcine CPB model. RESULTS: Platelet counts were significantly preserved in groups P and H compared with those in group C (P versus C, p < 0.05). The plasma levels of thrombin-antithrombin complex and bradykinin were significantly lower at 120 minutes in groups P and H than in group C (thrombin-antithrombin: P versus C, p < 0.05; bradykinin: P versus C, p < 0.05). The amount of fibrinogen adsorbed onto the hollow fibers was markedly less in group P than in groups C and H. CONCLUSIONS: The PMEA coating was equal to heparin coating in preventing reactions induced by CPB circuits, and might be superior to heparin coating in suppressing the adsorption of plasma proteins such as fibrinogen. Thus, PMEA coating may be a suitable means for improving the biocompatibility of CPB circuits.     

Clinical significance of bradykinin liberation during cardiopulmonary bypass and its prevention by a kallikrein inhibitor

Activation of the kinin system and effects of Trasylol (Bayer, A.G. Lebukusen, West Germany), a kallikrein inhibitor, were investigated on 52 patients during hemodilutional cardiopulmonary bypass (CPB). Immediately after the start of CPB, neither elevation of bradykinin nor reduction of plasma kininogen (KGN: a precursor of bradykinin) were observed. During CPB, bradykinin level in the blood was markedly elevated, correlating with the significant decrease of kininogen (p<0.001). The longer the CPB time, the more marked the reduction of KGN. In the cases requiring over 60 minutes of CPB, the amounts of bradykinin released (4.6–18.0ng/ml) were sufficient to increase capillary permeability as well as peripheral vasodilatation. As shown by the significant increase of hematocrit (p<0.005) and the extreme reduction of vascular resistance found at the end of CPB in the prolonged cases. Infusion of Trasylol into the extracorporeal circuit actually prevented the reduction of kininogen and the increase of hematocrit as well as the extreme decrease of vascular resistance in the cases of over 60 minutes CPB. These results clearly point out that Trasylol is beneficial for the prevention of bradykinin liberation and capillary permeability increase and for the maintenance of optimum peripheral vascular tone during CPB. Furthermore, the significance of these findings with regards to complications during and after prolonged CPB was discussed.     

Fluid extravasation during cardiopulmonary bypass in piglets--effects of hypothermia and different cooling protocols

BACKGROUND: Hypothermic cardiopulmonary bypass (CPB) is associated with capillary fluid leak and edema generation which may be secondary to hemodilution, inflammation and hypothermia. We evaluated how hypothermia and different cooling strategies influenced the fluid extravasation rate during CPB. METHODS: Fourteen piglets were given 60 min normothermic CPB, followed by randomization to two groups: 1: rapid cooling (RC-group) ( approximately 15 min to 28 degrees C); 2: slow cooling (SC-group) ( approximately 60 min to 28 degrees C). Ringer's solution was used as CPB prime and for fluid supplementation. Fluid input/losses, plasma volume, colloid osmotic pressures (plasma, interstitial fluid), hematocrit, serum-proteins and total tissue water (TTW) were measured and fluid extravasation rates calculated. RESULTS: Start of normothermic CPB resulted in a 25% hemodilution. During the first 5-10 min the fluid level of the reservoir fell markedly due to an intravascular volume loss necessitating fluid supplementation. Thereafter a steady state was reached with a constant fluid need of 0.14 +/- 0.04 ml kg-1 min-1. After start of cooling the fluid needs increased in the following 30 min to 0.91 +/- 0.11 ml kg-1 min-1 in the RC group (P < 0.001) and 0.63 +/- 0.10 ml kg-1 min-1 in the SC-group (P < 0.001) with no statistical between-group differences. Fluid extravasation rates after start of hypothermic CPB increased from 0.20 +/- 0.08 ml kg-1 min-1 to 0.71 +/- 0.13 (P < 0.01) and 0.62 +/- 0.13 ml kg-1 min-1 (P < 0.05) in the RC- and SC-groups, respectively, without any changes in degree of hemodilution. TTW increased in most tissues, whereas the intravascular albumin and protein masses remained constant with no between group differences. CONCLUSION: Hypothermia increased fluid extravasation during CPB independent of cooling strategy. Intravascular albumin and protein masses remained constant. Since inflammatory fluid leakage usually results in protein rich exudates, our data with no net protein leakage may indicate that mechanisms other than inflammation could contribute to fluid extravasation during hypothermic CPB.     

Beneficial effect of balloon-induced pulsatility on brain oxygenation in hypothermic cardiopulmonary bypass

BACKGROUND: Sufficient O2 delivery to meet the demand is an important factor for protecting the brain during cardiopulmonary bypass (CPB). This study was designed to investigate the influences of temperature, pulsatility of blood flow (intra-aortic balloon pump-induced) and flow rate during CPB on the cerebral oxygenation. METHODS: Patients were divided into five groups. Normothermia (36 degrees C): pulsatile (n=8, 2.5 L/min/m2), nonpulsatile (n=12, 2.5 L), and nonpulsatile perfusion (n=12, 2.8 L); hypothermia (30 degrees C): pulsatile (n=9, 2.5 L) and nonpulsatile perfusion (n=11, 2.5 L). The oxygen saturation (SjVO2), lactate and CPK-BB levels in the jugular venous blood were measured. RESULTS: In all of the normothermic groups, the SjVO2 value decreased during the CPB (p<0.1-0.01). No remarkable change was observed in the hypothermic groups, with the exception during the rewarming period in the nonpulsatile group. A higher SjVO2 and a lower frequency of SjVO2 values <50% were observed in the hypothermic pulsatile group, as compared with those in the normothermic groups (p<0.05). The levels of CPK-BB were nearly the same, however the levels of lactate were higher in the normothermic pulsatile and nonpulsatile (2.5 L) groups (p<0.05). CONCLUSIONS: We concluded that the hypothermic CPB was advantageous over normothermic CPB in regard to the SjVO2 levels and lactate production. The beneficial effect of intra-aortic balloon pump assist was only obtained in the hypothermic CPB.     

Hemodilution elevates cerebral blood flow and oxygen metabolism during cardiopulmonary bypass in piglets

BACKGROUND: Hemodilution continues to be widely used during cardiopulmonary bypass (CPB) for both adults and children. Previous studies with nonbypass models have suggested that an increase in cerebral blood flow (CBF) compensates for the reduced oxygen-carrying capacity; however, this increased CBF is achieved by an increase in cardiac output. We hypothesized that even with the fixed-flow perfusion of CPB, CBF would be increased during hemodilution. METHODS: Two experiments were conducted and analyzed separately. In each experiment, 10 piglets were randomized to two different groups, one with a total blood prime yielding a high hematocrit (25% or 30%), and the other with a crystalloid prime resulting in a low hematocrit (10% or 15%). Animals were cooled with pH-stat strategy at full flow (100 or 150 mL.kg(-1).min(-1)) to a nasopharyngeal temperature of 15 degrees C, a period of low flow (50 mL.kg(-1).min(-1)) preceding deep hypothermic circulatory arrest (45 or 60 minutes), and a period of rewarming at full flow. Cerebral blood flow was measured at the beginning of CPB, at the end of cooling, at the end of low flow, 5 minutes after the start of rewarming, and at the end of rewarming by injection of radioactive microspheres. RESULTS: Mean arterial pressure was significantly greater with higher hematocrit at each time point (p< 0.05). Cerebral blood flow and the cerebral metabolic rate of oxygen decreased during cooling and further during low flow bypass but were significantly greater with lower hematocrit during mild hypothermia and at the end of rewarming (p< 0.05). CONCLUSIONS: Hemodilution is associated with decreased perfusion pressure, increased CBF and increased the cerebral metabolic rate of oxygen during hypothermic CPB.     

Effect of immune response during cardiopulmonary bypass on post-operative infections

To study the effects of extracorporeal circulation on the post operative infections, the relationship between the influences of the immunologic change during cardiopulmonary bypass (CPB) and post operative change of neutrophilia was evaluated in 52 patients. These patients were divided into two groups: group A (non-infected), 19 patients whose neutrophil count increased within 15,000/microliters in peripheral blood after operation. Group B (infected), 33 patients whose neutrophil count increased 15,000/microliters or more within one week after operation. Immunoglobulins (IgG, IgA, IgM) and complement fraction (C3, C4, CH50) levels decreased significantly during CPB, but there was no significant difference between the two groups. The amount of lymphocyte subsets of helper/inducer T cell and suppressor/cytotoxic T cell showed similar change in both groups. On the contrary the amount of lymphocyte subset of Natural Killer cell showed significant increase in A group during CPB when compared with B group, suggesting immunological activation, however, in the group which showed less than 40% increase of NK cell during CPB, there was significant increase of neutrophils after operation compared with the other group which showed high increase of NK cell. These findings suggested the increased activation of the Natural Killer cell during CPB is a favorable response, especially for preventing infections after operation.     

Pulsed venous flow pattern with hemodilution.

Venous flow pattern changes and venous flow were assessed in relation to the degree of hemodilution. Femoral vein flow was measured with a duplex scanner in two groups of 11 patients 20 days and 5 days preoperatively, and 1 day postoperatively. In group I, hemodilution was used and patients gave three autologous blood predonations between day 20 and day 5. Perioperative blood loss was reintegrated by electrolyte solution. In group II, hemodilution was not used and autologous blood predonations were not carried out. These patients received a perioperative homologous blood transfusion of 800 mL. Hemoglobin was lower on day 5 (11.3 +/-1.4 vs 13.1 +/-1 g/dL, p<0.05) and on postoperative day 1 (8.9 +/-1.6 vs 10.6 +/-1, p<0.05) in group I. The decrease in hemoglobin was associated with an increase in blood flow and a pulsed venous flow pattern in 14 of 22 veins after autologous blood predonation and in 21 of 22 veins on postoperative day 1 (p<0.05). Increased venous flow in hemodilution is associated with a pulsed venous flow pattern.     

不同血液稀释方法对直肠癌患者围术期NK细胞和CIK细胞的影响

目的 比较急性非等容血液稀释(ANIH)和急性高容血液稀释(AHH)联合控制性降压(CH)对直肠癌患者围术期自然杀伤(NK)细胞和细胞因子诱导杀伤(CIK)细胞的影响.方法 择期直肠癌根治术患者45例,随机均分为ANIH组、AHH+CH组和对照组.分别于麻醉前1 h(T1)、术毕即刻(T2)、术后第1天(T3)、第4天(T4)抽取静脉血检测NK和CIK细胞的数量.结果 与T1时比较,T2～T4时AHH+CH组NK细胞明显升高(P＜0.05),T4时ANIH组NK细胞明显升高(P＜0.05),而对照组则明显降低(P＜0.05).与T1时比较,T2时三组CIK细胞均明显降低(P＜0.05),T4时ANIH组和AHH+CH组均明显升高(P＜0.05),且明显高于对照组(P＜0.05).结论 AHH联合CH以及ANIH均能使直肠癌患者NK和CIK细胞增加,AHH联合CH效果更优.     

Adrenocortical hormone levels during cardiopulmonary bypass with and without pulsatile flow

To determine the effect of hypothermic pulsatile and nonpulsatile cardiopulmonary bypass (CPB) with hemodilution on adrenocortical function we measured plasma levels of adrenocorticotropic hormone (ACTH), cortisol, aldosterone, and renin in two groups of patients. Group I, comprising 11 patients had routine CPB (nonpulsatile), and Group II, comprising 12 patients, had pulsatile flow during CPB (pulsatile). Both groups demonstrated comparable increases in cortisol, ACTH, and aldosterone with operation. Levels for all three hormones appeared to decline during CPB and then rose again in the post-CPB period. There were no significant differences between groups. Plasma renin activity gradually declined in a comparable manner in both groups. In the post-CPB period, renin activity was slightly higher in the nonpulsatile group (1.7 +/- 0.5 versus 0.8 +/- 0.2 ng/ml/hr, p less than 0.05). Correction for the effect of hemodilution demonstrated no decrease in cortisol and a slight increase in ACTH in both groups during CPB. Significant increases occurred in both groups during CPB in urinary Na+ excretion rate and urinary Na+/K+ ratio, more so for the nonpulsatile group. There was no correlation between urinary Na+/K+ ratios and either plasma cortisol or aldosterone levels. Thus routine CPB demonstrates no evidence of adrenocortical hypofunction and the addition of pulsatile flow produces little improvement.     

Hemodilution during cardiopulmonary bypass increases cerebral infarct volume after middle cerebral artery occlusion in rats

Although the optimal hematocrit during cardiopulmonary bypass (CPB) is not defined, excessive hemodilution may lead to organ ischemia via a reduction in oxygen-carrying capacity uncompensated by autoregulatory and/or rheologic increases in organ blood flow. As a result, the consequences of hemodilution in patients at risk for cerebral ischemia are not clearly understood. We designed this study to evaluate the effects of hemodilution in the setting of focal cerebral ischemia during CPB. Wistar rats surgically prepared for CPB were randomized to either hemodilution (hemoglobin (Hb), 6 g/dL; n = 9) or control (Hb, 11 g/dL; n = 8) groups and subsequently exposed to focal cerebral ischemia induced by middle cerebral artery occlusion (MCAO). Immediately after the onset of MCAO (maintained for 90 min), 65 min of hypothermic (28 degrees C) CPB was initiated. Twenty-four hours later, functional neurological outcome and cerebral infarct volume were determined. Compared with controls, the hemodilution group had worse neurological performance (new score = 8 [2], hemodilution; versus 10 [2], control; P = 0.030) and larger total cerebral infarct volumes (182 +/- 84 mm(3), hemodilution; versus 103 +/- 58 mm(3), control; P = 0.043). In this experimental model of CPB with reversible MCAO-induced focal cerebral ischemia, hemodilution worsened neurological function and increased cerebral infarct volume.     

Heparin-coated circuits reduce the formation of TNFα during cardiopulmonary bypass

Background: Cardiopulmonary bypass (CPB) causes a systemic intlammatory response. TNFα, which is a major inflammatory mediator, has been found in the circulation during and after CPB. Although previous studies have shown that heparin coating of the extracorporeal circuits reduces complement and granulocyte activation, and the inflammatory response, the possible effect of heparin coating on TNFα formation and the inflammatory response has not been fully investigated.
Methods: Eighteen patients scheduled for coronary artery bypass grafting were divided randomly into two groups. One group of patients had extracorporeal perfusion using heparin coated circuits (HC group, n = 9). The other group had extra-corporeal perfusion using an identical circuit that was not coated (UC group, n = 9). Blood samples were drawn before, during, and after CPB for measurement of plasma TNFα, plasma IL-8, neutrophil count, and neutrophil elastase.
Results: Plasma levels of TNFα increased during CPB in the UC group but not in the HC group. Plasma concentrations of IL-8 increased similarly during and after CPB in both groups. Coating the circuits with heparin did not affect the levels of IL-8. In both groups, the neutrophil count increased after the release of the aortic cross clamp and remained elevated for three days. In the HC group, however, the increase of neutrophil count was significantly lower compared with the UC group. Plasma concentrations of neutrophil elastase were significantly increased during and after CPB in both groups. However, the levels of elastase were significantly lower at certain time points in the HC group.
Conclusion: From these observations, we conclude that heparin coating of the extracorporeal circuits reduces the TNFα formation during CPB, which may reduce neutrophil activation.     

急性等容血液稀释用于心血管外科血液保护的效果

目的 比较急性等容血液稀释(ANH)联合术中血液回收与单纯术中血液回收用于心血管外科血液保护的临床效果。方法 将术前血红蛋白Hb≥130g/L的心血管外科成年病人140例随机分成两组:A+C组,ANH联合术中血液回收(ANH量 8～12ml/kg,n=70);C组,术中单纯血液回收(n=70)。分别记录两组病人术前及术后24h血红蛋白(Hb)、血球压积(HCT)、血小板(PLT);回收血量;体外循环(CPB)总转流时间;术后24h引流量;全血用量;血浆用量;悬浮红细胞用量;冷沉淀用量;血小板用量和总住院时间。结果 两组病人一般情况无显著差异,术前各实验室指标无显著差异;A+C组术中血液回收量(581.8±28.2)ml少于C组(785.4±43.8)ml,有显著差异(P<0.001);A+C组术后24hHb(122.2±18.8)g/l高于C组(112.3±15.6)g/l,有显著差异(P<0.01),HCT(35.2±5.5)高于C组(33.2±4.5),亦有显著差异(P<0.05);A+C组全血用量(81.7±23.0)ml少于C组(217.4±35.7)ml,有显著差异(P<0.01)A+C组有15例,C组有6例未输异体血;两组间CPB时间、总住院时间及其它血制品用量无显著差异。结论ANH联合术中血液回收比较术中单纯血液回收用于心血管外科血液保护可减少异体血需要及用量,值得推广。     

儿童胸腔镜心脏手术中奥美拉唑对胃肠道的保护作用

目的探讨奥美拉唑在婴幼儿胸腔镜体外循环(CPB)心脏手术中对胃肠道的保护作用。方法将127例先天性心脏病患者(年龄3～12岁)随机分为3组,实验组A和实验组B:行胸腔镜微创手术治疗,对照组:行常规手术治疗;实验组A在CPB预充液中给予奥美拉唑10mg,实验组B和对照组均注入等量生理盐水。3组均于术前、CPB30min、CPB结束、术后4h、24h进行胃液常规检查,并采集血液标本,用ELISA法测定血清促胃液素。结果与CPB前比较:实验组A胃液pH值较CPB结束后有明显升高(P<0.01),实验组B于术毕有明显降低(P<0.05),对照组于术后4h较术前有明显降低(P<0.05);3组胃液红细胞计数及血清促胃液素与CPB前比较均有明显上升(P<0.01)。与对照组比较:实验组A胃液pH于CPB结束后各时间点较对照组有明显上升,而胃液红细胞计数则有明显下降,血清促胃液素于CPB30min时即较其它两组有明显降低。实验组B胃液pH于术毕有明显降低,但术后24h恢复至术前水平,同时间点胃液红细胞计数与促胃液素则有明显降低。结论儿童胸腔镜心脏手术中CPB时间较常规手术时间长,需要在此期间进行胃肠道保护,术后各项指标恢复较常规手术时间短。     

两种自体输血方式在中央性前置胎盘孕妇中应用的安全性分析

目的探讨储存式自体输血和急性等容稀释式自体输血在中央性前置胎盘孕妇剖宫产术中应用的安全性及临床疗效。方法选择2013年1月至2016年9月在我院因中央性前置胎盘拟行剖宫产术的60例患者为研究对象。采用随机数字表的方法平均分为两组:A组为储存式自体输血组,B组为急性等容稀释式自体输血组。观察两组患者自体输血采血前后及手术后的血红蛋白(Hb)、血细胞比容(Hct)、血小板计数(PLT)、术中出血量、输血量、新生儿Apgar评分及Hb水平、输血不良反应等。结果两组患者出血量及输血量比较无显著性差异(P0.05)。两组患者采血前后及手术后的Hb、Hct、PLT比较亦无显著性差异(P0.05)。两组新生儿1分钟Apgar评分及Hb水平比较无显著性差异(P0.05)。两组患者中输注自体血的患者均未发生输血不良反应,术后恢复良好;输注异体血的患者中,B组仅有1例出现发热、皮疹,未出现严重不良反应。结论储存式自体输血和急性等容稀释性自体输血在应用安全性上无明显差异。在基层医院临床工作中,针对中央性前置胎盘患者,由于剖宫产输血率高,可以在综合评估患者具体情况后,对必要的患者选择自体输血。     

Hemoglobin levels and weight gain after coronary bypass grafting by use of intraoperative hemodilution and autologous blood transfusion

We investigated the relationship between the degree of hemodilution during cardiopulmonary bypass (CPB) and weight gain after coronary bypass grafting by use of intraoperative hemodilution and autologous blood transfusion. There is no significant difference in weight gain between the higher hemoglobin group (Hb > or = 6 g.dl-1) and the lower hemoglobin group (Hb < 6 g.dl-1). Furthermore, there is no significant correlation between hemoglobin levels during CPB and weight gain after operation. We conclude that slightly excessive hemodilution than usual during CPB does not influence weight gain when cardiac and renal functions are fair.     

脊柱手术患者急性高容量血液稀释联合控制性降压及自体血液回收的效应

目的 评价脊柱手术患者急性高容量血液稀释(AHH)联合控制性降压及自体血液回收的效应.方法 择期行脊柱手术患者30例,随机分为2组(n=15):控制性降压联合自体血液同收组(Ⅰ组)和AHH联合控制性降压及自体血液回收组(Ⅱ组),Ⅱ组手术前输注6%羟乙基淀粉130/0.4(10 mi/kg)和复方乳酸钠林格氏液10 ml/kg,速率为30 ml/min.2组均在手术开始后静脉输注尼卡地平行控制性降压,速率为1.0～6.0 μg·kg-1·min-1,在lO～15min使MAP降至65～70mm Hg,直至脊柱内固定安器安装完毕.2组术中均行自体血液回收,于脊柱内固定器安装完毕后回输.术中持续监测血液动力学参数,记录术中异体输血情况、尿最及术后引流量、异体输血量.不良反应的发生情况.结果 2组术中HR和CVP均保持稳定.与Ⅰ组比较,Ⅱ组术中异体输血免除率升高,异体输血量减少(PO.05),尿量增多(P0.05).2组均末见心、脑、肾功能异常的发生.结论 脊柱手术患考AHH联合控制性降压及自体血液回收可减免异体输血.     

Reduction of the inflammatory response following coronary bypass grafting with total minimal extracorporeal circulation.

OBJECTIVE: Cardiopulmonary bypass (CPB) is known to cause part of the systemic inflammatory reaction after cardiac surgery that can be responsible for organ failure. A novel technique based on a minimal extracorporeal circulation (MECC(R)) system has been evaluated with regard to the inflammatory response in a prospective study involving patients undergoing coronary artery bypass grafting. METHODS: Sixty consecutive patients were randomly assigned to either standard normothermic CPB (n=30) or the MECC system, with a reduced priming volume, no aortic venting and no venous reservoir, excluding the blood-air interface (n=30). Specific evaluation of cytokine release (IL-1beta, IL-6, TNF-alpha), as well as neutrophil elastase secretion and beta-thromboglobulin release from platelets and S100 protein assay were performed. Serial blood samples were taken prior to the onset, after initiation, at the end and after weaning of the CPB; further samples were collected 6 and 24h after the end of the CPB. RESULTS: All patients were similar with regards to pre- and intra-operative characteristics and clinical outcomes were comparable for both groups. MECC system allowed a reduced hemodilution with a mean drop of the hematocrit of 8.5 vs. 15.3% (P<0.05). Mononuclear phagocytes dropped in a more important manner under standard CPB conditions (247+/-151 vs. 419+/-168, P=0.002), but both groups demonstrated a rise in monocyte count at the end of the CBP. No significant release of IL-1beta was observed in either group. By the end of CPB, IL-6 levels were significantly lower in the MECC group (38.8+/-19.6 vs. 87.9+/-78.9, P=0.04), despite a higher monocyte count. Plasma levels of TNF-alpha rised significantly more during standard CPB than with the MECC system (17.8+/-15.4 vs. 10.1+/-5.6, P=0.002). With MECC, the neutrophil elastase release was reduced (72.7+/-47.9 vs. 219.6+/-103.4, P=0.001). Platelet count remained at higher values with the minimal compared to standard CPB. It is noteworthy to consider that beta-thromboglobulin levels showed slightly lower platelet activation in the MECC group at all times of CPB (110.5+/-55.6 vs. 134.7+/-46.8, P=0.10). The pattern of release of S100 protein showed higher values in patients undergoing standard CPB than after MECC. CONCLUSIONS: The MECC system is suitable to maintain total extracorporeal circulation and demonstrates a lower inflammatory reaction when compared to standard CPB.     

Biocompatibility of heparin-coated cardiopulmonary bypass circuits in coronary patients with left ventricular dysfunction is superior to PMEA-coated circuits

BACKGROUND: Several coating techniques for extracorporeal circulation have been developed to diminish the systemic inflammatory response during cardiopulmonary bypass (CPB). The aim of this study was to evaluate the clinical effectiveness and biocompatibility of heparin-coated and poly-2-methoxyethylacrylate (PMEA)-coated CPB circuits on coronary patients with left ventricular systolic dysfunction. METHODS: Thirty-six patients who underwent elective coronary artery bypass grafting were divided into two equal groups: group H (n = 18), heparin-coated; group P (n = 18), PMEA coated. Clinical outcomes, hematologic variables, cardiac enzymes, malondialdehyde (MDA), and acute phase inflammatory response (including myeloperoxidase (MPO), catalase, hsCRP, and IL-8) were analyzed perioperatively. RESULTS: Demographic, CPB, and clinical outcome data were similar for both groups. Plasma fibrinogen, total protein, albumin, and platelet count decreased, neutrophil count, MDA, IL-8, MPO, and catalase levels increased during CPB. During CPB, MPO and catalase values were significantly higher in group P (p = 0.02 and p = 0.01) and postoperative MDA concentration was lower in group H (p = 0.03). Platelet counts were better preserved in group H during and after CPB but neutrophil count and IL-8 level did not differ between the groups. Postoperative total protein, albumin, and fibrinogen levels were higher in group H (p < 0.05). The postoperative first day levels of troponin-I, CK-MB, and CRP increased in both groups without any significant differences between the groups. CONCLUSIONS: Heparin-coated circuit provided better suppression of perioperative inflammatory markers and exhibited more favorable effects on hematologic variables than PMEA-coated circuit.