A New Evaluation Q-Factor to Be Calculated for Suction Geometries as a Basis for Smooth Suction in the Operating Field to Ensure the Highest Possible Blood Integrity for Retransfusion Systems.

Blood hemolysis caused by mechanical impact is a serious problem in medicine. In addition to the heart-lung machine (artificial surfaces, flow irritating connection points) which contributes to hemolysis, blood suction and surgical suction devices are influencing factors. Goal of our research is to develop best flow optimizing suction geometry that represents the best compromise between all influencing effects. Based on data that negative pressure and turbulence have a negative impact on blood components, 27 surgical suction tips have been examined for acoustic stress and negative pressure behavior. Furthermore, a dimensionless factor Q was introduced to assess the overall performance of the suction tips investigated.

Abrupt hemodynamic changes accompanying intrapleural hyperthermic chemotherapy: Case series.

RATIONALE: Intrapleural hyperthermic chemotherapy (IPHC) is the preferred method to locally treat lung cancer with pleural seeding. Anesthetic management during IPHC is a very challenging task for the anesthesiologist because of the hemodynamic instability associated with the procedure; however, there is no report on anesthetic considerations during the IPHC procedure. PATIENT CONCERNS: Three patients who diagnosed lung cancer with pleural invasion scheduled for IPHC were reported in this case series. DIAGNOSIS: Case 1, a 48-year-old woman, suffered from lung cancer (adenocarcinoma, T2NxM1a) with diffuse pleural seeding. Case 2, a 58-year-old female, diagnosed with lung cancer (adenocarcinoma, T3N0M1a) with pleural dissemination. Case 3, a 47-year-old male, diagnosed as sarcoma on the left lung with right pericardial invasion and right hemidiaphragm invasion (stage, T3N0M1a). INTERVENTION: All three patients underwent IPHC with cisplatin diluted in normal saline (2000 ml) at a rate of 600 ml/min. Inflow temperature of 42°C was using a heart-lung machine over 90 minutes. Hemodynamic changes were monitored through the procedure. OUTCOMES: The patient did not require supplemental oxygenation anymore after he recovered from lung transplantation. LESSONS: There was sudden drop in the cardiac output and an increase in the pulmonary vascular resistance, which were caused by the volume and temperature of the hyperthermic chemotherapeutic drugs in the pleura during the early stage of IPHC; these changes can be a major problem during the procedure, and supportive hemodynamic management may be needed.

Measurement of ventilation- and perfusion-mediated cooling during laser ablation in ex vivo human lung tumors.

PURPOSE: Perfusion-mediated tissue cooling has often been described in the literature for thermal ablation therapies of liver tumors. The objective of this study was to investigate the cooling effects of both perfusion and ventilation during laser ablation of lung malignancies. MATERIALS AND METHODS: An ex vivo lung model was used to maintain near physiological conditions for the specimens. Fourteen human lung lobes containing only primary lung tumors (non-small cell lung cancer) were used. Laser ablation was carried out using a Nd:YAG laser with a wavelength of 1064 nm and laser fibers with 30 mm diffusing tips. Continuous invasive temperature measurement in 10 mm distance from the laser fiber was performed. Laser power was increased at 2 W increments starting at 10 W up to a maximum power of 12-20 W until a temperature plateau around 60 °C was reached at one sensor. Ventilation and perfusion were discontinued for 6 min each to assess their effects on temperature development. RESULTS: The experiments lead to 25 usable temperature profiles. A significant temperature increase was observed for both discontinued ventilation and perfusion. In 6 min without perfusion, the temperature rose about 5.5 °C (mean value, P<0.05); without ventilation it increased about 7.0 °C (mean value, P<0.05). CONCLUSION: Ventilation- and perfusion-mediated tissue cooling are significant influencing factors on temperature development during thermal ablation. They should be taken into account during the planning and preparation of minimally invasive lung tumor treatment in order to achieve complete ablation.

Circulating particles during cardiac surgery.

Shed blood is known to be a source of lipid micro-emboli in cardiac surgery. The aim of this study was to characterize the occurrence of these particles at different stages of the operation, and to study their occurrence in the circulation at multiple time-points after the retransfusion of shed blood. Forty-four patients undergoing routine surgery with cardiopulmonary bypass were included. Blood was sampled from the surgical field at different sampling locations during the operation. Shed blood was collected in a transfusion bag and retransfused. After which, blood was sampled from the arterial line of the heart-lung machine. A Coulter counter was used for particle determinion. The mean volume of shed blood collected was 340+/-215 ml. Particles in the size range 10-60 microm were found at varying concentrations, with the highest concentrations being found in blood collected after cannulation and from the pleura. After retransfusion of this blood, a biphasic response was seen in the blood drawn from the efferent line of the heart-lung machine. Particles are found in shed blood at all times during cardiac surgery, and when this blood was retransfused an increase was seen in particle concentration in the heart-lung machine.

Pharmacokinetics of tissue plasminogen activator in an isolated extracorporeal circuit.

PURPOSE: The aim of this study was to investigate the pharmacokinetics of tissue plasminogen activator (tPA) under the conditions of an isolated extracorporeal circuit. METHODS: Plasma levels of tPA were measured in the perfusion solution and in central venous blood before, during, and after the perfusion in seven patients undergoing regional hyperthermic fibrinolytic perfusion with tPA in addition to surgical thrombectomy for extended deep venous thrombosis. RESULTS: After 15 minutes of fibrinolytic perfusion, the level of tPA in the perfusion solution was 10,427 +/- 4432 ng/mL, and after 30 minutes the maximum level of 19,726 +/- 5630 ng/mL was reached. After 60 minutes when the perfusion was discontinued, tPA concentrations dropped to 15,931 +/- 4818 ng/mL. In central venous blood, tPA levels increased to a maximum of 230.7 +/- 89.6 ng/mL after 60 minutes of perfusion, which represented 1.4% of the concentration measured in the perfusion solution at the same time. With disconnection of the extracorporeal circuit, the tPA levels in central venous blood decreased rapidly and reached a level of 24.1 +/- 8.7 ng/mL after 120 minutes. CONCLUSION: The use of regional hyperthermic fibrinolytic perfusion in the treatment of extended deep venous thrombosis makes it possible to achieve extremely high concentrations of tPA in the perfusion solution. At the same time, the entry of the fibrinolytic agent into the systemic circulation is minimized.

Isolation limb perfusion with tumor necrosis factor alpha and chemotherapy for advanced extremity soft tissue sarcomas.

The unique property of high dose recombinant tumor necrosis factor alpha (rTNF alpha) is to activate and selectively destroy the tumor-associated microvasculature. For the systemic application of rTNF alpha it has been shown that the maximum tolerated dose (MTD) is 10 times less than the effective dose in animals. The main toxicity corresponds to systemic inflammatory response syndrome with a decrease in vascular resistance and hypotension. We found that it is possible to administer rTNF alpha at 10 times the MTD in an isolated limb perfusion (ILP) system with heart-lung machine, for locally advanced extremity soft tissue sarcomas. One hundred forty patients received an ILP with high-dose TNF alpha. In 55 patients treated with the combination of high-dose rTNF alpha + interferon-gamma + melphalan an overall objective response rate of 87% with 36% complete responses was observed; it was 81% and 28%, respectively, in a group treated with TNF alpha and melphalan (n = 85). Angiographic and immunohistological studies showed the selective and early damage of the sarcoma-associated microvasculature preceded by the upregulation of adhesion molecules and intratumoral leak of von Willebrand factor. Tumor invasion by platelets and, in some cases, by polymorphonuclear cells, appeared within hours after the application of rTNFa long before the lysis of the tumor. Thus, ILP with high-dose TNF alpha and chemotherapy seems to act through a dual targeting: TNF hits the tumor associated vasculature, and chemotherapy attacks the tumor cells. Therefore, ILP with TNF is a new option in the management of locally advanced soft tissue sarcoma of the extremities.

Cardiopulmonary bypass and cell-saver technique in combined oncologic and cardiovascular surgery.

The purpose of this study was to work out an adequate operative technique for patients with malignant tumors who also need open heart surgery or procedures on major blood vessels. We had 8 such patients. In 6 of them, a tumor (3 cases hypernephroid cancer and 3 cases retroperitoneal sarcoma) had grown through the inferior vena cava (IVC) up to the right atrium. Two patients had lung cancer together with severe coronary artery disease. All of these patients were operated on using a heart-lung machine (HLM) and cell saver (CS). In 6 patients the intravascular portion of the tumor was extracted as much as possible through a right atrium approach (in 3 cases a nephrectomy was performed). Two patients had a one-stage coronary artery bypass graft (CABG) and a lobectomy. All of the patients had uneventful postoperative periods and were alive when checked on 1 year after the procedures. During cytological investigation after each operation, tumor cells were found only on the internal surface of the HLM arterial filters with 20 microns holes. We suggest that special cardiovascular devices such as the HLM and CS might be used in borderline situations in oncology without increasing the risk of hematogenous tumor dissemination.

[Intraoperative (hyperthermic) intraperitoneal chemotherapy--considerations and aspects of safe intra- and postoperative treatment with cytostatic drugs]. / Intraoperative (hypertherme) intraperitoneale Chemotherapie-Uberlegungen und Aspekte zum sicheren intra- und postoperativen Umgang mit Zytostatika.

The application of open intraoperative intraperitoneal chemotherapy following cytoreductive surgery for the treatment of pseudomyxoma peritonei or peritoneal carcinomatosis requires safety precautions for the medical and non-medical personnel. In agreement with already existing rules, precautions were established which result in an optimum of safety. These concern the preparation of the cytostatic drugs, the application in the operating room as well as personal precautions intra- and postoperatively. After the establishment of theses recommendations, 22 patients were treated with open intraperitoneal chemotherapy in 1.5 years without any severe accidents. Therefore, a safe intraoperative use of cytotoxic drugs is possible. At the moment, the indication for such an approach may be given in peritoneal carcinomatosis from appendix, colon or ovarian cancer. In the future, an adjuvant application in other gastrointestinal malignancies (e.g. T3/T4 gastric carcinoma) may be considered.

Potassium-reduced lung preservation solutions: a screening study.

In recent years several potassium-reduced solutions have been developed for improvement of pulmonary preservation. A comparison of these solutions in a single study, however, has not yet been performed. In an extracorporeal working rat heart-lung model (n = 7/group) lungs were preserved with 20 ml Euro-Collins (EC), low potassium EC (LPEC), low potassium 2% dextran (LPD), ET-Kyoto (ETK) or low potassium 5% dextran (Perfadex) solution, while hearts were arrested with 10 ml St. Thomas' cardioplegia. Lungs of controls were not perfused. The heart-lung blocks were stored for 2 h at 10 degrees C. Thereafter, heart-lung blocks were extracorporeally perfused with Krebs-Henseleit solution with washed bovine red blood cells. Coronaries were perfused with oxygenated perfusate. Lungs were perfused via the working right ventricle with deoxygenated perfusate and ventilated with room air. Oxygenation capacity (dPO2) and pulmonary vascular resistance (PVR) were measured. Reperfusion/ventilation was performed for 40 min. At the end of the experiment the wet to dry (W/D) ratio of lungs and light microscopic assessment of the degree of edema (0-4) were performed. All potassium-reduced solutions showed superior dPO2 and a lower PVR than EC and controls while LPEC exhibited the most stable dPO2 and lowest PVR after 30 min reperfusion. The W/D ratio of all potassium-reduced groups was lower than the ratio of EC and controls. In LPEC, ETK and Perfadex the least degree of edema was noted. All solutions used in this study are superior to regular EC. However, when compared directly, LPEC perfused lungs showed better functional preservation than all other alternative solutions.

Leukocyte depletion results in improved lung function and reduced inflammatory response after cardiac surgery.

Leukocyte depletion during cardiopulmonary bypass has been demonstrated in animal experiments to improve pulmonary function. Conflicting results have been reported, however, with clinical depletion by arterial line filter of leukocytes at the beginning of cardiopulmonary bypass. In this study, we examined whether leukocyte depletion from the residual heart-lung machine blood at the end of cardiopulmonary bypass would improve lung function and reduce the postoperative inflammatory response. Thirty patients undergoing elective heart operations were randomly allocated to a leukocyte-depletion group or a control group. In the leukocyte-depletion group (n = 20), all residual blood (1.2 to 2.1 L) was filtered by leukocyte-removal filters and reinfused after cardiopulmonary bypass, whereas in the control group an identical amount of residual blood after cardiopulmonary bypass was reinfused without filtration (n = 10). Leukocyte depletion removed more than 97% of leukocytes from the retransfused blood (p < 0.01) and significantly reduced circulating leukocytes (p < 0.05) and granulocytes (p < 0.05) compared with the control group. Levels of the inflammatory mediator thromboxane B2 determined at the end of operation (p < 0.05) were significantly lower in the depletion group than in the control group, whereas no statistical differences in interleukin-6 levels were found between the two groups. After operation, pulmonary gas exchange function (arterial oxygen tension at a fraction of inspired oxygen of 0.4) was significantly higher in the leukocyte-depletion group 1 hour after arrival to the intensive care unit (p < 0.05) and after extubation (p < 0.05). There were no statistical differences between the two groups with respect to postoperative circulating platelet levels and blood loss, and no infections were observed during the whole period of hospitalization. These results suggest that leukocyte depletion of the residual heart-lung machine blood improves postoperative lung gas exchange function and is safe for patients who are expected to have a severe inflammatory response after heart operations.

[Regional hyperthermic fibrinolytic perfusion as ultima ratio in critical ischemia of the lower extremities]. / Regionale hypertherme Fibrinolytika-Perfusion als ultima ratio bei kritischer Ischämie der unteren Extremitäten.

In 19 patients (male-female: ratio 10:9; median age 67.1 (42-90) years) with a critical ischaemia of the lower extremities either after failed attempt of revascularization (n = 4) or because of lacking possibility for vessel reconstruction measures (n = 16) a regional extremity perfusion with a fibrinolytic agent has been performed using a heart lung machine. In one patient both lower extremities were treated. In the first 30 minutes of the total 60 minutes perfusion time on average 31 mg (20-50 mg) of recombinant tissue-plasminogen activator (Actilyse) have been added to the perfusion solution. In order to enhance the fibrinolysis-activity the perfusion solution was warmed up to 40 degrees C. Systemic side effects have not been observed. Two patients died postoperatively because of their underlying diseases (mesenteric artery embolism, myocardial infarction), two patients experienced postoperative haemorrhage and one patient had a wound infection. In 11 cases (55%) an opening of the stem-arteries has been reached. Seven of these were successfully revascularized with a femoro-crural bypass in a following operation. Nine extremities (45%) remained without opening of the stem-arteries, however, in four cases (20%) an improved radiographic contrast of the collaterals has been reached. 11 (61%) of the followed-up extremities were successfully revascularized. Amputation has been performed in seven cases (39%). The regional hyperthermic perfusion with fibrinolytic drugs enables a reopening of the stem-arteries and the creation of accepting vessels for vascular procedures in primarily inoperable arterial occlusions.

[Operations with a heart-lung machine in adult members of Jehovah's Witnesses]. / Operationen mit der Herz-Lungen-Maschine bei erwachsenen Patienten der Glaubensgemeinschaft "Zeugen Jehovahs".

Members of Jehovah's Witnesses refuse blood transfusions and blood products under any circumstances. Because of an improvement in blood salvage techniques in our centre, they are not excluded from open-heart surgery. In recent years recombinant human erythropoietin (rhEPO) has been applied to correct perioperative anemia in these patients. METHODS. Seventeen members of Jehovah's Witnesses who were more than 18 years of age were operated on using various blood salvage technique, e.g., haemoseparation and a high dose of Aprotinin. We present the first three patients treated with 4 x 500 U of i.v. rhEPO/kg body wt. given within 11 days preoperatively. Thirteen of the patients operated on had elevated preoperative risk factors, for instance poor left ventricle, severe aortic valve stenosis, metabolic syndrome, age older than 70 years, etc. In other centres that perform cardiac operations on members of Jehovah's Witnesses, these risk factors represent contraindications for open-heart surgery in these patients. RESULTS. Patients with rhEPO treatment showed a preoperative hematocrit increase of 7 Vol.% within 10 days and no postoperative complications. At the 6th postoperative hour the hematocrit returned to the starting values; in patients without rhEPO, however, the hematocrit generally had not increased to preoperative values even by the 8th day after operation. In 9 patients with preoperative elevated risk factors and a postoperative relative decrease in hematocrit below 33% we observed an uncomplicated postoperative period. Four patients with these risk factors, a pronounced decrease in hematocrit and blood loss postoperatively had various severe complications. CONCLUSIONS. Preoperative treatment with a high dose of rhEPO to enhance the hematocrit and maturity by precursor red blood cells in patients with a hematocrit below 45 Vol.% is a possibility to compensate for the blood loss perioperatively and to avoid complications from a decrease in oxygen transport capacity. The anaemia and high blood loss postoperatively are the main causes for a slightly elevated operation risk in members of Jehovah's Witnesses in all heart centres that perform cardiac operations on these patients. Nevertheless, Jehovah's Witnesses should be not excluded from cardiac operations, since open-heart surgery without use of homologous blood is becoming a routine procedure.

[Surgical treatment of acute Stanford Type-A aortic dissection].

Twelve cases of Stanford Type-A aortic dissection were operated in an acute phase. The male vs female ratio was 3:9, and their ages ranged from 47 to 79 (mean 61.3) years old. Most of them complained of chest and/or back pain, and four of them complained of syncope. Eight patients had the history of hypertension. As to the complications of aortic dissection, cardiac tamponade was seen in two cases, myocardial infarction in one, and transient hemiplegia and paraplegia in one case each. In five cases, moderate to severe aortic regurgitation was also noted. All but one case were operated within twenty-four hours after admission. The replacement of the ascending aorta with a tube graft was performed in all cases including the two cases whose entries were located in the aortic arch. CABG was done concomitantly in three cases, and aortic valve replacement and CABG in one case. The open distal anastomosis was carried out under the systemic circulatory arrest combined with the retrograde cerebral perfusion. The systemic perfusion was reinstituted after the distal anastomosis was completed. In cases whose dissecting pseudo-lumen of the distal aorta was not thrombosed, the arterial cannulation site was shifted from the femoral artery to the tube graft. All but two cases were discharged from the hospital in good condition. One case, who had been transferred to the operating room under cardiac massage due to myocardial infarction, was lost by severe LOS three weeks postoperatively.(ABSTRACT TRUNCATED AT 250 WORDS)

Experimental studies of the influence of priming solutions on the systemic activation of complement during cardiopulmonary bypass: comparison between the use of albumin, hydroxyethyl starch and HWA-138.

Cardiopulmonary bypass surgery may be complicated by a systemic inflammatory reaction, which has been ascribed to activation of complement. For such activation, the choice of priming solution for the heart-lung machine may be of importance. The peripheral blood of three groups of eight donors was exposed to albumin, hydroxyethyl starch (HES) or to HWA-138 (pentoxifylline analogue) in addition to the priming solutions. The study confirmed that activation of complement is a consistent phenomenon during cardiopulmonary bypass surgery. The concentration of the C3 activation product C3a in the plasma was significantly increased after simulated extracorporeal circulation. However there were no differences within the increase of C3a concentrations between the various priming solutions.

[Regional hyperthermic fibrinolytic perfusion in postoperative deep venous thrombosis of the leg]. / Regionale hypertherme Fibrinolytika-Perfusion bei postoperativer tiefer Beinvenenthrombose.

Four days after an operation for fusion of lumbar and sacral vertebrae a 30-year-old man developed bilateral deep-vein thrombosis in the legs, extending on the left from the fibular group of veins to the popliteal vein. On the right all deep veins of the lower leg were occluded, including the confluence of the popliteal vein. As systemic fibrinolysis was contraindicated, surgical thrombectomy was undertaken. After incomplete removal of the thrombi, regional hyperthermic perfusion with streptokinase was performed using a heart-lung machine. After a compression bandage had been applied to the right leg above the veins the leg was perfused via the common femoral vein at 40 degrees C from the heart-lung machine, at a flow rate of 600-800 ml/min, for 60 min with a solution containing 1 million IU streptokinase. Measurement of various components in the perfusate indicated marked fibrinolysis (fibrinogen: not measurable; fibrinogen breakdown products: > 80 micrograms; streptokinase: 100 FU/ml after 30 min, 62 FU/ml after 60 min). At the same time there was no demonstrable fibrinolytic activity in the systemic circulation. Fibrinogen concentration fell from 340 mg/dl 30 min before the onset of perfusion to 245 mg/dl 90 min after it. After 60 min of perfusion the blood from the right leg was discarded and the leg flushed through with 1.5 l of an electrolyte solution and then filled up with previously obtained and stored patient's own blood concentrate. Subsequent phlebography and venous occlusion plethysmography demonstrated complete recanalization of the deep-vein system with normal venous valve function.

[A case report of successful surgical treatment following the emergency circulatory assist by percutaneous cardiopulmonary support system for acute postinfarction left ventricular free wall rupture].

Percutaneous cardiopulmonary support system (PCPS) was applied for a 85 years old man with circulatory collapse caused by left ventricular free wall blow out rupture following acute anterior myocardial infarction. PCPS was started after the cardiac massage for 7 minutes without thoracotomy or release of cardiac tamponade and flow of ranging from 2.3 to 2.7 L/min/m2 was achieved. The patient was transferred to operating room and closure of the ventricular rupture was performed under the usual cardiopulmonary bypass. Postoperative recovery of cardiac function and consciousness was satisfactory but he was died of multiple organ failure caused by sepsis at 36 postoperative day. PCPS and consecutive surgical therapy seemed useful method for the treatment of left ventricular free wall blow out rupture.