室缺并重度肺动脉高压的手术适应证和围术期处理

自１９８９年５月至１９９６年５月，我们在中低温体外循环下行室间隔缺损（ＶＳＤ）修补术３５７例，死亡１１例，死亡率３．１％；其中合并重度肺动脉高压（ＰＨ）者３０例，死亡６例，死亡率２０％。可见影响ＶＳＤ手术效果的主要因素是合并重度ＰＨ。通过对ＶＳＤ合并...     

230例婴幼儿室间隔缺损的外科治疗

目的 探讨外科手术治疗婴幼儿室间隔缺损（ＶＳＤ）的结果和经验。方法 对１９９０年２月至１９９７年１２月的２３０例婴幼儿ＶＳＤ修补术进行总结。年龄３￣３６个月,体重３．２￣１５．５ｋｇ。膜周部ＶＳＤ１９２例,干下型ＶＳＤ３６便,膜周部并肌部ＶＳＤ２例,术前中度以上肺动脉高压１５０例（６５．２％）。结果 全组手术死亡１３例,手术病死率为５．６５％。手术死亡的主要原因为肺动脉高压危象和严重心律失常。术后     

心内直视术中鱼精蛋白毒性反应2例

例１女，６岁。室间隔缺损（ＶＳＤ）并肺动脉高压。１９４年１１月在体外循环下手术。ＶＳＤ为膜周型，直径１．５ｃｍ，补片修补。术中阻断循环４０分钟，开放循环后心跳有力，平均动脉压１０ｋＰａ（１ｋＰａ＝７．５ｍｍＨｇ），经锁骨下静脉给予鱼精蛋白（批号：９３...     

肺动脉瓣下室间隔缺损的外科治疗

我院自１９７４年５月～１９９８年４月共施行室间隔缺损（ＶＳＤ）修补手术１０７０例,其中肺动脉瓣下室间隔缺损（ＳＰＶＳＤ）１９３例,占１８％（不包括法洛四联症的ＳＰＶＳＤ）。由于ＳＰＶＳＤ部位特殊,且常合并主动脉瓣脱垂及主动脉瓣关闭不全（ＡＩ）,因此,此型ＶＳＤ与常见的膜部室间隔缺损（ＭＶＳＤ）的外科治疗有所不同。现对本组病例的临床特点和手术治疗加以分析和讨论。１　临床资料与方法本组１９３例中,男１１２例,女８１例。年龄２～３５岁,平均９．４±５．５岁。体重１０～５９ｋｇ,平均２５．２±１２．１ｋ…     

风心病二尖瓣狭窄合并小左心室的瓣膜替换术

１９８７～１９９３年３８９例二尖瓣狭窄（ＭＳ）行二尖瓣替换术（ＭＶＲ）的病人中有小左室者１２６例，其中左室萎缩２８例。心功能ＩＩＩ级７６例、ＩＶ级３５例，重度肺动脉高压６４例。手术死亡率９５％，明显高于同期非小左室病人。主要死亡原因为右心衰、急性左心衰及瓣膜功能障碍。晚期死亡率为１６％／病人－年，１、５年生存率为９６５％和８８４％。术后心脏超声显示小左室及左室萎缩者均出现左室构形和功能的重建，后者重建过程较长。结果表明，小左室主要影响术后早期效果，重度ＭＳ合并小左室，尤其是伴有严重肺动脉高压及左室萎缩，是手术的高危指标。     

室间隔缺损合并右室流出道狭窄的手术治疗

室间隔缺损合并右室流出道狭窄的手术治疗王占明赵希武郑有仁高峰１９８８年１１月至１９９５年５月我们手术治疗室间隔缺损（ＶＳＤ）合并右室流出道狭窄（ＲＶＯＴＳ）２４例，占同期先心病手术总数的２．３％。现报告如下：临床资料２４例中男１６例，女８例。术前诊断...     

146例严重肺动脉高压者二尖瓣替换术疗效分析

评价风湿性二尖瓣病变伴重度肺高压病人的手术效果。采用方差分析、卡方检验对肺动脉收缩压（ＳＰＡＰ）≥９．３３ｋＰａ（１ｋＰａ＝７．５ｍｍＨｇ）并接受二尖瓣替换术（ＭＶＲ）的１４６病人的临床资料进行分析，将其分为４组。Ａ组：极重度肺高压（ＳＰＡＰ≥１３．３ｋＰａ）；Ｂ组：心功能严重低下组（心脏指数ＣＩ≤３３．３４）；Ｃ组：心功能减低或正常组（３３．３４≤ＣＩ≤６６．６８）；Ｄ组：高心排血量组（ＣＩ≥６６．６８）。其中每组按一次和二次手术再分为２个亚组。结果示一次手术组总死亡率为５．３％；Ａ１、Ｂ１、Ｃ１、Ｄ１４组术前临床情况、所用术式和心脏阻断时间等无差异，但Ｂ１组低心排（２４．２％）早期死亡率（１５．２％）明显高于其它３组（Ｐ＜０．０５），而Ｄ组无死亡。二次手术组总死亡率为２８．２％；各亚组低心排及死亡率均明显高于一次手术各组。由此认为，二尖瓣病变伴重度肺动脉高压病人，ＭＶＲ后低心排和早期死亡率与术前心脏指数有关。当心脏指数＞３３．３４时，即使肺动脉压和全肺阻力同时极度增高者，术后低心排和死亡率亦不因此增加。当ＣＩ＜３３．３４时，术后低心排及早期死亡率较高。重度肺动脉高压者施行二次ＭＶＲ手术时风险性较大     

先天性心脏病室间隔缺损并肺动脉高压围手术期监护

先天性心脏病室间隔缺损并肺动脉高压围手术期监护西安医科大学第二附属医院李淳成，陈光华我院１９８７～１９９２年收治先天性心脏病室间隔缺损合并肺动脉高压患者９５例。其中重度肺动脉高压４０例（ＰＰ／ＰＳ＞０．５），护理体会如下。１临床资料９５例中男５５例，...     

婴幼儿室间隔缺损伴肺动脉高压手术治疗的围术期处理

随着心脏手术技巧和体外循环技术的不断提高,国内婴幼儿室间隔缺损（ＶＳＤ）伴肺动脉高压（ＰＨ）患者的手术治疗日益增多,而围术期的处理对于手术成功和术后的恢复起着很大的作用［１］。我们于１９９３年１１月～１９９７年６月收治了５１例３岁以下ＶＳＤ伴中至重度...     

室间隔缺损合并肺动脉高压术后的呼吸道管理

室间隔缺损合并肺动脉高压术后的呼吸道管理西安医科大学第一临床学院李民霞先天性心脏病室间隔缺损合并肺动脉高压（ＶＳＤ·ＰＨ），随着外科手术治疗成功率的提高，死亡率的下降，其术后在ＩＣＵ呼吸道管理占有举足轻重的地位。我院１９８４年５月至１９９０年１１月行...     

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.     

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.     

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.     

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.     

Is the recovery profile of mivacurium independent of the rate of decay of its plasma concentration in patients with normal plasma cholinesterase activity?

Background: The duration of action of muscle relaxants is poorly correlated to the rate of decay of their plasma concentration. The plasma concentration of mivacurium may rapidly decrease below its active concentration because of the extensive hydrolysis of mivacurium. By inflating a tourniquet on one upper limb for 3 min after the administration of atracurium, mivacurium or vecuronium, we studied the influence of the initial decline of their plasma concentration on their effect. Methods: In 50 patients anaesthetised with thiopental, isoflurane and fentanyl, the effect of bolus doses of 0.15 or 0.25 mg . kg^?1 mivacurium (MIV 15, MIV 25), 0.3 or 0.5 mg . kg^?1 atracurium (ATR 30, ATR 50) and 0.06 or 0.1 mg . kg^?1 vecuronium (VEC 06, VEC 10) were measured on both arms (evoked response of the adductor pollicis to train-of-four stimulation every 12 s), a tourniquet being applied on one arm just before and during 3 min after the muscle relaxant bolus. Results: Tourniquet inflation of 3 min almost abolished the neuromuscular effect of mivacurium. In the vecuronium groups and in the ATR 50 group, tourniquet inflation did not modify the maximum degree of depression of the twitch response. Also, the duration of action of vecuronium was unaffected by the tourniquet. In the ATR 30 group, times to return of the twitch response to 25% (duration 25%) and 75% (duration 75%) of control response were significantly shorter in the cuffed arm, 23 min vs 27 min, and 41 min vs 45 min, respectively. In the ATR 50 group, only duration 25% was significantly shorter in the cuffed arm (41 min vs 45 min). Conclusion: The results suggest that the rate of decline of the plasma concentration of mivacurium is so rapid, that a very low and almost clinically ineffective concentration is present as soon as 3 min after its administration. The results also indicate that the recovery from a mivacurium-induced neuromuscular blockade is not influenced by the rate of decay of its plasma concentration in patients with genotypically normal plasma cholinesterase.     

Membranes in Artificial Organs

Abstract: Membrane processes play a pivotal and enabling role in modern replacement therapy for acute and chronic organ failure and in the management of immunologic diseases. In fact, virtually all contemporary extracorporeal blood purification methods employ membrane devices, and the next generation of artificial organs and tissue engineering therapies are almost certain to be similarly grounded in membrane technology. In this short essay, we comment on the similarities and differences among synthetic membranes and their natural counterparts and also provide a critical overview of the demographics and technology of hemodialysis, hemofiltration, apheresis, oxygenation, and emerging membrane technologies and applications.     

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.     

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.