心脏外科手术病人选择性的肺血管扩张剂

由于缺少选择性肺血管扩张剂,因此对肺动脉高压病人还无有效治疗措施,吸入低浓度一氧化氮(NO)(<80ppm)作为内皮衍生松弛因子(EDRF)可以扩张肺血管而不影响全身血流动力学。我们对二尖瓣置换及/或冠状动脉搭桥术于体外循环前、后肺血管阻力(PVR)不同水平的病人吸入低浓度NO(22ppm)后血流动力学改变给予评估。同时研究需要循环支持而给以心室辅助装置的患者吸入NO后的效果。     

PGE1与NO对先天性心脏病术后肺动脉高压疗效的对比研究

目的比较静脉应用前列腺素E1(PGE1)和吸入外源性一氧化氮(NO)对先天性心脏病(先心病)术后中重度肺动脉高压的治疗效果.方法对12例术后存在中重度肺动脉高压的先心病病人,进行前瞻性、交叉、随机试验研究.分别应用PGE1(30ngkg-1min-1)、NO(30ppm)、PGE1+NO,检测用药前后心率(HR)、平均动脉压(mSAP)、平均肺动脉压(mPAP)、中心静脉压(CVP)、肺毛细血管嵌压 (PCWP)、心排指数(CI)、肺血管阻力(PVR)和体血管阻力(SVR)等血液动力学参数.同时检测吸入NO前后二氧化氮(NO2)和高铁血红蛋白(MetHb)的浓度.结果 PGE1和NO在降低mPAP和PVR方面均有非常显著的疗效(P＜0.01),但联合应用(PGE1+NO)并未显示出较单纯应用更明显的效果.对mPAP和PVR降低的幅度比较,PGE1和NO之间差异无显著性(P＞0.05).NO对肺血管有更强的选择性,但PGE1在提高CI方面明显优于NO(P＜0.05).吸入NO后,NO2和MetHb的浓度明显高于吸入前(P＜0.01),但仍在正常范围内.结论 PGE1和NO对先心病合并的中重度肺动脉高压均有显著的治疗作用,二者的作用效果相近.考虑到NO的潜在毒性和PGE1在提高心功能方面的良好效果,在临床上首选合适剂量的PGE1更合理可行.     

先天性心脏病术后肺动脉高压的一氧化氮吸入治疗

目的　探讨先天性心脏病(先心病)术后肺动脉高压(肺高压)病儿吸入一氧化氮(NO)的适应证、避免毒副作用等。方法　选择31例先心病术后传统治疗无效的、难治的反应性肺高压或肺高压危象病儿,给予NO吸入治疗。试验分NO吸入前、中、后3个阶段,各阶段均进行各项血液动力学指标的测定。结果　吸入不同浓度NO［10～80百万分之体积(ppm)］后,平均肺动脉压力和体肺循环压力之比分别降低了34.8%和45.0%(P＜0.01),有效率为87.1%;吸入NO后二氧化氮、高铁血红蛋白含量明显高于吸入前(P＜0.05),但仍在允许范围。结论　吸入NO可明显降低先心病术后难治的反应性肺高压或肺高压危象病儿的肺动脉压力和肺血管阻力,临床上未发现明显的毒副作用。因此,NO是一种有效、安全、理想的肺血管扩张剂。     

心脏移植患者术前肺动脉压力与术后并发症的关系及防治

目的分析心脏移植患者术前肺动脉压力和肺血管阻力（PVR）与术后右心功能不全、并发症发生和死亡的关系,总结围术期肺动脉高压的管理经验,以利于心脏移植术后患者早期心功能的恢复。方法125例接受同种原位心脏移植手术的患者,根据术前肺动脉收缩压（PASP）和PVR不同分为两组,肺动脉高压组（n=56）：术前PASP〉50 mm Hg或PVR〉5 Wood.U;对照组（n=69）：术前PASP≤50 mm Hg,PVR≤5 Wood.U。通过Swan-Ganz导管监测两组手术前心脏排血指数（CI）,手术前、后肺动脉     

慢性血栓栓塞性肺动脉高压合并严重右心功能衰竭患者治疗的病例对照研究

目的探讨肺动脉内膜剥脱术(PEA)治疗慢性血栓栓塞性肺动脉高压(CTEPH)合并严重右心功能衰竭(RHF)患者的安全性与有效性。方法回顾性分析2015年1月至2016年4月阜外医院行PEA 36例患者的临床资料,其中男28例、女8例,平均年龄(46.56±11.85)岁。根据纽约心脏病协会(NYHA)心功能分级将36例患者分为术前合并严重RHF组(Ⅲ~Ⅳ级,n=28)及术前未合并严重RHF组(Ⅱ级,n=8),对PEA手术前后血流动力学参数进行统计并进行3~18个月短中期随访。结果 36例患者PEA术后,肺动脉平均压、肺血管阻力术后均有显著性改善[肺动脉平均压由(49.58±13.14)mm Hg降至(23.58±10.79)mm Hg,肺血管阻力由(788.46±354.60)dyn·s/cm~5降至(352.89±363.49)dyn·s/cm~5,P0.001]。全组患者无院内死亡。术后发生持续性肺动脉高压2例,灌注肺2例,心包积液2例,随访期间未发生死亡,其中34例患者心功能改善至NYHAⅠ~Ⅱ级(WHOⅠ~Ⅱ级CTEPH),仅2例患者仍维持在NYHAⅢ级(P0.01)。术后超声随访仅2例患者仍存在持续性肺动脉高压(定义为超声预测肺动脉收缩压40 mm Hg)。结论 PEA作为CTEPH患者治疗方案,可显著改善患者血流动力学结果从而改善患者术后心功能、提高患者生存质量。     

球囊肺血管成形术治疗血栓栓塞性肺动脉高压患者的临床疗效

目的 探讨球囊肺血管成形术(BPA)治疗血栓栓塞性肺动脉高压患者的临床疗效.方法 收集遂宁市中心医院2017年1月至2020年6月采取BPA手术治疗的80例血栓栓塞性肺动脉高压患者临床资料.统计患者术后并发症发生情况、肺动脉直径(肺动脉主干直径和右肺动脉直径)、肺动脉压[肺动脉收缩压(PASP)、肺动脉舒张压(PADP...     

风湿性心脏病合并肺动脉高压瓣膜置换病人血浆肾上腺髓质素的变化及作用

目的　观察风湿性心脏病(风心病)合并肺动脉高压病人瓣膜置换术前后血浆肾上腺髓质素(AM)、内皮素-1（ET-1）、一氧化氮(NO)及肺血流动力学的变化。方法　37例风心病病人手术前后采用放射免疫法测定血浆AM、ET-1浓度,采用测定血浆亚硝酸盐/硝酸盐含量来反映NO水平,采用Swan-Ganz浮导管测定肺血流动力学指标。结果　严重肺动脉高压组病人术前血浆AM、ET-1水平明显高于正常肺动脉压组(P＜0.05);术后1周各组血浆AM水平都有不同程度的下降,而严重肺动脉高压组血浆ET-1水平无明显下降;术后严重肺动脉高压、肺动脉高压组血浆NO水平有一个降低及再恢复的过程;术前血浆AM/ET-1比值水平与肺血管阻力呈负相关(r=－0.503,P＜0.01),术后48h血浆AM/ET-1比值与平均肺动脉压、肺血管阻力呈负相关（r=－0.524、－0.551,P＜0.05）。结论　AM在风心病肺动脉高压的形成和术后缓解过程中发挥了拮抗ET-1的作用,血浆AM/ET-1的比值与术后肺动脉高压的改善有关。     

吸入一氧化氮对室间隔缺损手术后肺动脉高压的疗效观察

目的　观察吸入一氧化氮(nitricoxide,NO)治疗室间隔缺损 (ventricularseptaldefect,VSD)术后肺动脉高压 (pulmonaryhypertension ,PH)的疗效。 方法　 2 0例VSD术后PH病人分别吸入 2 0×10 -6 、6× 10 -6 NO ,监测吸入前后的血流动力学、氧合指标。结果　吸入 2 0× 10 -6 NO后明显降低肺动脉压、肺循环阻力、肺内分流率、肺泡动脉血氧分压差 ,提高动脉血氧分压、氧供指数 ;以上指标停吸NO后恢复吸入NO前水平 ;再吸入 6× 10 -6 NO后恢复吸入 2 0× 10 -6 NO后水平 ,并维持至停吸NO后。吸入前后体循环压及阻力无变化。结论　吸入NO是治疗VSD手术后PH的一种有效的方法。     

一氧化氮在肺动脉高压中的作用

目的　探讨肺动脉高压 (PH)时一氧化氮 (NO)的介导作用及吸入NO对肺、体循环压力和肺血管结构重组逆转的影响。方法　 6条PH模型犬 ,采用面罩法间断吸入NO 1周 ,检测肺组织一氧化氮合酶 (NOS)、丙二醛 (MDA)及总钙含量 ;观察吸入NO后血流动力学及动脉血气变化 ;图像分析法测定肺小动脉中膜厚度 (MT) ;监测外周血高铁血红蛋白 (MetHb)含量。结果　PH时 ,肺组织NOS活性为 (0 .5 2± 0 .2 7)nmol·min-1·g-1,较正常明显降低 (P <0 .0 5 ) ,MDA、Ca2 含量明显升高 (P <0 .0 5 )。吸入NO后肺动脉平均压、肺血管阻力明显降低 ,氧分压升高 ,二氧化碳分压降低 ,而体动脉压无变化。吸入NO前后肺小动脉中膜厚度无明显变化 (P >0 .0 5 )。MetHb均低于正常值 15 g/L。结论　NO作用减弱在PH形成中与NOS活性降低密切相关 ,O-2 和Ca2 共同介导 ;吸入NO能选择性降低肺动脉压而不影响体动脉压 ,但对肺血管结构无影响。     

心脏移植期间吸入NO比PGE_1更能降低肺循环阻力

原位心脏移植后出现右心衰竭与肺循环阻力(PVR)升高有关,后者往往预示此类病人早期死亡率较高。前列腺素E1(PGE1)是一种有效的非选择性肺血管扩张剂,在降低心脏移植期间PVR升高的同时也明显降低体循环阻力(SVR)应用受到限制。与PGE1不同的是,吸入一氧化氮(NO)选择性地扩张肺血管而对体循环影响很小,近年来已被用于降低肺动脉高压。本研究目的是比较二者在原位心脏移植在停机和围术期对PVR的影响。     

Vasopressor hormone response following mesenteric traction during major abdominal surgery

Background : We investigated the vasopressor hormone response following mesenteric traction (MT) with hypotension due to prostacyclin (PGI₂) release in patients undergoing abdominal surgery with a combined general and epidural anesthesia. Methods : In a prospective, randomized, placebo-controlled study we administered 400 mg ibuprofen (i.v.) in 42 patients scheduled for abdominal surgery. General anesthesia was combined with epidural anesthesia (T4-L1). Before as well as 5, 15, 30, 45, and 90 min after MT we recorded plasma osmolality, hemodynamics and measured 6-keto-PGFlα (stabile metabolite of PGI₂), TXB₂ (stabile metabolite of thromboxane A₂) active renin, and arginine vasopressin (AVP) plasma concentrations by radioimmunoassay. Catecholamine levels were assessed by high-pressure liquid chromatography (HPLC) with electrochemical detection. Results : Following MT, arterial hypotension occurred along with a substantial PGI₂ release. This was completely abolished by ibuprofen administration. Although plasma levels of 6-keto-PGF_1α (1133 (708) vs. 60 (3) ng/L, median (median absolute deviation), P=0.0001, placebo vs. ibuprofen) remained significantly elevated, blood pressure was restored within 30 min after MT in the placebo group. At the same point in time plasma concentrations of TXB² (164 (87) vs. 58 (1) ng/L, P=0.0001), epinephrine (46 (33) vs. 14 (6) ng/L, P=0.001), AVP (41 ± (18) vs. 12 (7) ng/L, P=0.0004), and active renin (27 (12) vs. 12 (4) ng/L, P = 0.001) were significantly higher in placebo-treated patients. Conclusion : Under combined general and epidural anesthesia arterial hypotension following MT due to endogenous PGI₂ release is associated with enhanced release of AVP, active renin, epinephrine and thromboxane A₂, presumably contributing to hemodynamic stability within 30 min after MT.     

A Teaspoon Pump for Pumping Blood with High Hydraulic Efficiency and Low Hemolysis Potential

Abstract: Virtually all blood pumps contain some kind of rubbing, sliding, closely moving machinery surfaces that are exposed to the blood being pumped. These valves, internal bearings, magnetic bearing position sensors, and shaft seals cause most of the problems with blood pumps. The original teaspoon pump design prevented the rubbing, sliding machinery surfaces from contacting the blood. However, the hydraulic efficiency was low because the blood was able to "slip around" the rotating impeller so that the blood itself never rotated fast enough to develop adequate pressure. An improved teaspoon blood pump has been designed and tested and has shown acceptable hydraulic performance and low hemolysis potential. The new pump uses a nonrotating "swinging" hose as the pump impeller. The fluid enters the pump through the center of the swinging hose; therefore, there can be no fluid slip between the revolving blood and the revolving impeller. The new pump uses an impeller that is comparable to a flexible garden hose. If the free end of the hose were swung around in a circle like half of a jump rope, the fluid inside the hose would rotate and develop pressure even though the hose impeller itself did not "rotate"; therefore, no rotating shaft seal or internal bearings are required.     

Microspheres Based Detoxification System: A New Method in Convective Blood Purification

Abstract: A variety of protein-bound or hydrophobic substances, accumulating as a result of pathologic conditions such as exogenous or endogenous intoxications, are removed poorly by conventional detoxification methods because of low accessibility (hemodialysis), insufficient adsorption capabilities (hemosorption), low efficiency (peritoneal dialysis), or economic limitations (high-volume plasmapheresis). Combining advantages of existing methods with microspheric technology, a module-based system was designed. Major operating parameters of the latter can be modified to allow for adjustment to individual clinical situations. An extracorporeal blood circuit including a plasmafilter is combined with a secondary high-velocity plasma circuit driven by a centrifugal pump. Different microspheric adsorbers can be combined in one circuit or applied in sequence. Thus, a prolonged treatment can be tailored using specially designed selective adsorber materials. Comparing this system with existing methods (high-flux hemodialysis, molecular adsorbent recycling system), results from our in vitro studies and animal experiments demonstrate the superior efficiency of substance removal.     

A comparison of the inhibitory effects of four volatile anaesthetics on the metabolism of chlorzoxazone, a substrate for CYP2E1, in rabbits

Background: Halothane inhibits in vitro and in vivo activity of cytochrome P-450 (CYP) 2E1. There are several fluorinated volatile anaesthetics besides halothane, and most of them are defluorinated by CYP2E1. It is unclear whether other fluorinated anaesthetics inhibit the in vivo activity of CYP2E1.
Methods: We compared the inhibitory effects of therapeutic concentrations of four inhalational anaesthetics, halothane, enflurane, isoflurane, and sevoflurane, on chlorzoxazone metabolism in rabbits receiving artificial ventilation.
Results: All four inhalational anaesthetics decreased arterial blood pressure and increased plasma chlorzoxazone concentration. However, no significant differences in the plasma chlorzoxazone concentration were found between the four anaesthetics. The estimated chlorzoxazone clearance increased after beginning inhalation with all four agents, but no significant difference in clearance was noted between agents.
Conclusions: At therapeutic concentrations, the in vivo inhibitory effect on chlorzoxazone metabolism was similar for all four inhalational anaesthetics examined, even though their chemical characteristics and extent of hepatic metabolism differ considerably.     

Tissue perfusion in relation to cardiac output during continuous positive-pressure ventilation and administration of propranolol or verapamil

Background : Our objective was to determine whether administration of propranolol or verapamil modifies the hemodynamic adaptation to continuous positive-pressure ventilation (CPPV), in particular the regional distribution of cardiac output (CO).
Methods : General hemodynamics and regional blood flows assessed by microsphere technique (15 (μm) were recorded in 16 anesthetized pigs during spontaneous breathing (SB) and CPPV with 8 cm H₂O end-expiratory pressure (CPPV8) before and after intravenous administration of propranolol (0.3 mg · kg⁻¹ followed by 0.15 mg · kg⁻¹ · h⁻¹, n=8) or verapamil (0.1 mg · kg⁻¹ followed by 0.3 mg · kg⁻¹ · h⁻¹, n=8).
Results : CPPV8 depressed CO by 25% without shifts in its relative distribution with the exception of a noteworthy increase in adrenal perfusion. Propranolol increased arterial blood pressure, and due to a fall in heart rate, CO dropped by 25%. The kidneys and, to a lesser extent, the splanchic region and central nervous system received increased fractions of the remaining CO at the expense of skeletal muscle flow. Similar patterns were seen during SB and CPPV8 such that the combination of propranolol and CPPV8 depressed CO by 50%. The circulatory effects of verapamil were less evident but myocardial perfusion tended to increase.
Conclusions : The combination of propranolol or verapamil with CPPV does not result in any specific hemodynamic interaction in anesthetized pigs, except that the combined effect of propranolol and CPPV may severely reduce CO.     

Bariatric Surgery in Some "Central and East-European (former Eastern bloc)"Countries - Current Status and Prediction for the Next Millennium

Background: Obesity is increasing globallly, including in the formerly "Eastern Bloc" countries. Methods: A survey was made of obesity and bariatric surgery. Results: In the 8 East and Central European countries studied, with total population 300 million, roughly 43% of the population was overweight (BMI 25-30), 23% obese (BMI > 30), with about 15 million people morbidly obese (BMI > 40). From 0-10 morbidly obese individuals/100,000/year undergo bariatric surgery. Conclusion: Most countries were found to provide inadequate treatment for obesity.The majority of the morbidly obese are not treated effectively. However, health-care awareness of obesity and bariatric surgeons are slowly increasing.     

Volatile anaesthetics reduce adhesion of blood platelets under low-flow conditions in the coronary system of isolated guinea pig hearts

Background : Inhibitory effects of volatile anaesthetics on platelet aggregation have been demonstrated in several studies. However, the influence of volatile anaesthetics on intracoronary platelet adhesion has not been elucidated so far.
Methods : Isolated hearts of guinea pigs were perfused with buffer in the absence or presence of volatile anaesthetics (0.5 and 1 MAC) at constant coronary flow rates of 5 ml/min for 25 min, then 1 ml/min for 30 min and again 5 ml/min for 10 min. Before, during and after low-flow perfusion, a bolus of human platelets was applied into the coronary system. To simulate thrombogenic conditions, 0.3 U/ml human thrombin was infused during low-flow perfusion and reperfusion. The number of platelets sequestered to the endothelium was calculated from the difference between coronary in- and output of platelets. The myocardial production of lactate and consumption of pyruvate and coronary perfusion pressure were also determined.
Results : At a flow rate of 5 ml/min only about 3% of the applied platelets did not emerge from the coronary system, in any group. In contrast, 13.1±1.2% (mean±SEM) of infused platelets became adherent in low-flow perfusion in the control group without anaesthetic. The adherence was reduced with each 1 MAC isoflurane (to 6.2±1.2%), sevoflurane (to 4.4±0.9%) or halothane (to 3.2±1.5%) (each P <0.05 vs. control). Volatile anaesthetic, 0.5 MAC, did not inhibit platelet adhesion to a statistically significant extent in any case. Perfusion pressure and metabolic parameters were not statistically different between the control and the hearts exposed to anaesthetics.
Conclusion : Volatile anaesthetics in a concentration of 1 MAC can reduce the adhesion of platelets in the coronary system under reduced flow conditions. This action does not arise from vasodilation or inhibition of ischaemic stress.     

Synergistic interaction between the effects of propofol and midazolam with fentanyl on phrenic nerve activity in rabbits

Background: It has been shown that the depressive effects of both propofol and midazolam on consciousness are synergistic with opioids, but the nature of their interactions on other physiological systems, e. g. respiration, has not been fully investigated. The present study examined the effect of propofol and midazolam alone and in combination with fentanyl on phrenic nerve activity (PNA) and whether such interactions are additive or synergistic. Methods: PNA was recorded in 27 anaesthetised and artificially ventilated rabbits. In three groups, propofol, fentanyl and midazolam were administered intravenously in incremental doses to construct dose-response curves for the depressant effects of each one on PNA. In another two groups, the effect of pretreatment with either fentanyl 1 μg · kg^?1 i. v. or midazolam 0.05 mg · kg^?1 i. v. on the effects of propofol and fentanyl respectively on PNA were studied. Results: Propofol and fentanyl caused a dose-dependent depression of PNA with complete abolition at the highest total doses of 16 mg · kg^?1 i. v. and 32 μg · kg^?1 i. v., respectively. In contrast, midazolam in incremental doses to a total of 0.8 mg · kg^?1 reduced mean PNA by 63%, but approximately 12% of PNA remained at a total dose as high as 6.4 mg · kg^?1. The mean ED₅₀s, calculated from dose-response curves, were 5.4 mg · kg^?1, 3.9 μg · kg^?1 and 0.4 mg · kg^?1 for propofol, fentanyl and midazolam, respectively. Initial doses of either fentanyl 1 μg · kg^?1 i. v. or midazolam 0.05 mg · kg^?1 i. v. acted synergistically with subsequent doses of either propofol or fentanyl to abolish PNA at total doses of 8 mg · kg^?1 and 8 μg · kg^?1, respectively. Conclusion: Fentanyl has a synergistic interaction with both propofol and midazolam on PNA and hence potentially on respiration.     

Influence of dopexamine hydrochloride on haemodynamics and regulators of circulation in patients undergoing major abdominal surgery

Background: Catecholaminergic support is often used to improve haemodynamics in patients undergoing major abdominal surgery. Dopexamine is a synthetic vasoactive catecholamine with beneficial microcirculatory properties. Methods: The influence of perioperative administration of dopexamine on cardiorespiratory data and important regulators of macro- and microcirculation were studied in 30 patients undergoing Whipple pancreaticduodenectomy. The patients received randomized and blinded either 2 μg · kg^?1 · min^?1 of dopexamine (n=15) or placebo (n=15, control group). The infusion was started after induction of anaesthesia and continued until the morning of the first postoperative day. Endothelin-1 (ET-1), vasopressin, atrial natriuretic peptide (ANP), and catecholamine plasma levels were measured from arterial blood samples. Measurements were carried out after induction of anaesthesia, 2 h after onset of surgery, at the end of surgery, 2 h after surgery, and on the morning of the first postoperative day. Results: Cardiac index (CI) increased significantly in the dopexamine group (from 2.61±0.41 to 4.57±0.78 1 · min^?1 · m^?2) and remained elevated until the morning of the first postoperative day. Oxygen delivery index (DO₂I) and oxygen consumption index (VO₂I) were also significantly increased in the dopexamine group (DO₂I: from 416±91 to 717±110 ml/m² · m²; VO₂I: from 98±25 to 157±22 ml/m² · m²), being significantly higher than in the control group. pHi remained stable only in the dopexamine patients, indicating adequate splanchnic perfusion. Vasopressive regulators of circulation increased significantly only in the untreated control patients (vasopressin: from 4.37±1.1 to 35.9±12.1 pg/ml; ET-1: from 2.88±0.91 to 6.91±1.20 pg/ml). Conclusion: Patients undergoing major abdominal surgery may profit from prophylactic perioperative administration of dopexamine hydrochloride in the form of improved haemodynamics and oxygenation as well as beneficial influence on important regulators of organ blood flow.     

Systemic analgesia adapted to the children's condition

A concept of balanced analgesia using nonsteroidal anti-inflammatory drugs (NSAIDs), paracetamol (acetaminophen), opioids, and corticosteroids can also be used in patients with pre-existing illnesses. NSAIDs are the most effective treatment for acute pain of moderate intensity in children; however, these drugs should be avoided in patients at increased risk for serious side effects, e.g. patients with renal impairment, bleeding tendency, or extreme prematurity. NSAIDs can be given with minimal risks to the younger child with mild to moderate asthma, and, in these patients, the use of steroids can be encouraged; in addition to their antiemetic and analgesic action, a beneficial effect on asthma symptoms can be expected. In the non-intubated child with cerebral trauma, exaggerated sedation caused by opioids and increased bleeding tendency caused by NSAIDs must be avoided. In neonates and small infants, the oral administration of sucrose or glucose is helpful to minimize pain reaction during short uncomfortable interventions.