带真皮下血管网皮片的耳郭复合组织游离移植的实验研究

目的探讨真皮下血管网皮片对耳郭复合组织成活率的影响.方法对24只兔切取楔形耳郭复合组织块,一侧带真皮下血管网皮片,一侧不带,换位移植,自身对照,进行大体观察、荧光染色、组织学观察及成活面积测定.结果①带真皮下血管网皮片侧较不带侧组织坏死少,血管密度高,统计学处理P＜0.05及P＜0.01;随时间延长,差异程度变小;同一时间内随宽度增加,组织坏死明显.②成活率两组间除2.1cm宽度组P＞0.05外,余统计学处理均有显著性;随宽度增大,成活率显著性下降.结论带真皮下血管网皮片减少了超宽径耳复合组织移植早期因缺血而发生的不可逆损害,是提高成活率的有效方法.     

大张真皮下血管网皮片成功移植的临床经验

1077年塚田贞夫首先报告真皮下血管网皮片游离植皮法。我们在1981～1983年间曾在临床行真皮下血管网皮片移植,因当时对此种皮片的血供方式及成活机理不甚了解,故成活率不稳定。自1992年以来我们在进行真皮下血管网皮瓣、皮管、皮片血供及成活方式实验研究的基础上,应用大张真皮下血管网移植修复不同部位缺损与畸形,皮片成活率高,修复效果好。     

真皮下血管网皮片基底血运建立的研究

为探讨真皮下血管网皮片基底血运对皮片成活的作用，采用５４只豚鼠，观察了真皮下血管网皮片边缘血运阻断时基底血运建立的情况，以及厚薄不一的皮片移植后成活情况。结果：真皮下血管网皮片边缘血运阻断时，皮片仍可成活。结论：真皮下血管网皮片基底部血运对皮片成活起重要要作用，临床上可以修剪成厚薄不一的真皮下血管网皮片进行移植。     

真皮下血管网皮片基底血运建立的研究

为探讨真皮下血管网皮片基底血运对皮片成活的作用，采用５４只豚鼠，观察了真皮下血管网皮片边缘血运阻断时基底血运建立的情况，以及厚薄不一的皮片移植后成活情况。结果：真皮下血管网皮片边缘血运阻断时，皮片仍可成活。结论：真皮下血管网皮片基底部血运对皮片成活起重要作用，临床上可以修剪成厚薄不一的真下下血管网皮片进行移植。     

应用真皮下血管网皮片治疗眼睑分裂痣

目的 总结应用带真皮下血管网皮片移植治疗眼睑分裂痣的经验,探讨大面积分裂痣的治疗效果及方法.方法 完整切除包括眼、眉在内的分裂痣,保留泪点、睑板以及睑结膜的痣组织,取带真皮下血管网皮片移植于受区.结果 21例患者的皮片全部成活,眼睑无变形,皮片无挛缩,泪道通畅,外形满意.结论 带真皮下血管网皮片移植可有效修复分裂痣切除后创面,其颜色、质地、外观良好,适用于较大面积眼睑分裂痣的修复.     

大张真皮下血管网皮片成功移植的临床经验

临床应用真皮下血管网皮片修复颜面14例、足16例、手8例、上肢4例、胸前1例组织缺损共43例53处均获成功。皮片面积最大600cm~2,用于修复全颜面缺损。43例中40例皮片100％成活,1例98％成活、92％成活1例,成活90％的1例。证明真皮下血管网皮片游离移植成活率高、修复质量优良、适应症广泛。凡适合传统中厚及全厚植皮的创面真皮下血管网皮片都能成活良好。认为仔细修剪皮片,保留完整的真皮下血管网是皮片成活的首要因素。创面有健康肉芽组织生长是真皮下血管网成活的第二个要素。应避免在需用皮瓣修复的大面积骨关节裸露创面、溃疡及褥疮创面、放射     

真皮下血管网皮片移植的系列研究

用家猪为实验动物,研究了真皮下血管网皮管、皮瓣、皮片的血供方式及成活规律。皮管是研究真皮下血管网皮瓣血供的良好模型。用成活长度、ECT 测定核素分布范围等方法证明超长真皮下血管网皮瓣的远侧部份得不到来自蒂部的血供,这种皮瓣实际上是真皮下血管网皮瓣与皮片的复合物。超长超宽真皮下血管网皮瓣(树叶状)实际上大部分不是皮瓣而是皮片。实验及临床研究结果表明:富含真皮下血管网的供皮区;保持真皮下血管网完整无损及皮下脂肪厚度不超过3mm;受区创面状况良好;在30mmHg(4kPa)左右的压力下持续加压包扎17天是保证真皮下血管网皮片成活的四个要素。报告了包括面积在600～1000cm~2的大张真皮下血管网皮片在内的88例(102个皮片)临床成功经验。用局部加热,术后肌注抗缺氧药物和双氧水皮片下滴注的方法分别使带有4mm 厚脂肪的猪真皮下血管网皮片的成活率达到93.5±5.8%,94.0±8.2%,84.0±4.3%。     

负压封闭引流技术联合带真皮下血管网皮片移植修复足部感染性创面

目的探讨负压封闭引流（VSD）技术联合带真皮下血管网皮片移植修复足部感染性创面的疗效。方法对25例足部感染性创面患者使用VSD技术联合带真皮下血管网皮片移植修复。结果25例均获随访,时间3～6个月,23例伤口一期愈合,2例出现部分坏死,经换药延期愈合。结论采用VSD技术联合带真皮下血管网皮片移植是修复足部感染性创面的有效方法。     

提高带有较厚皮下脂肪的真皮下血管网皮片成活率的实验研究

带脂肪厚度为2～3mm 的真皮下血管网皮片移植在我们的动物实验及临床应用中成活率都很高(见本系列研究)。为使真皮下血管网皮片移植的修复效果更好,我们以小猪为实验动物,对带有较厚皮下脂肪的真皮     

SVN皮片在面部组织缺损修复中的应用

目的：评估真皮下血管网游离皮片修复面部组织缺损的疗效。方法：对20例面部组织缺损的病人应用带真皮下血管肉皮片游离植皮修复面部组织缺损。结果：所有病例2周后拆线时皮片全部成活,术后3个月随访,病人全部满意。结论：带真皮下血管网皮片游离移植修复面部组织损方法简便,手术效果肯定,值得推广。     

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.     

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.     

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.     

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.