Coronary artery bypass grafting without cardiopulmonary bypass and without interruption of native coronary flow using a novel anastomosis site restraining device ("Octopus").

OBJECTIVE: This study assessed the feasibility of coronary artery bypass grafting on the beating heart without interruption of native coronary blood flow using a novel anastomosis site restraining device. BACKGROUND: Recently, an end-to-side bypass technique was described that does not require interruption of flow in the recipient artery. METHODS: By means of a suction device ("Octopus"), in 31 pigs the epicardium was grasped and immobilized through an arm contraption fixed to the operating table. In the first 15 consecutive pigs (study I), the two-dimensional motion of an epicardial beacon was monitored. In 16 subsequent pigs (study II), an internal mammary artery was grafted under the microscope in two steps to a proximal coronary artery segment, without cardiopulmonary bypass. First, the internal mammary artery was sutured end-to-side to the outside of the coronary artery. Secondly, an orifice was punched in the partitioning coronary wall by an excimer laser catheter introduced through a temporary side-branch of the internal mammary artery. RESULTS: Study II: During 43 suction periods in four anastomosis areas, immobilization was achieved for 15 to 169 min (>30 h in total) in 13 open- and 9 closed-chest procedures without hemodynamic deterioration. The area circumscribed by the edges of the beacon trajectory (area in which the anastomosis is to be tracked) was reduced from 73.0 +/- 43.0 mm(2) (mean +/- SD) to 1.3 +/- 0.5 mm(2) (p<0.001) in the open-chest and to 0.2 +/- 0.2 mm(2) in the closed-chest procedure. At 6 weeks, no myocardial or coronary suction lesions were found. Study II: Nonocclusive anastomosis surgery required 25 +/- 3 min. No leakage, serious arrhythmias, graft closure or hemodynamic deterioration occurred during the procedure or for 2 h after ligating the coronary artery proximally. At 6 weeks, all seven grafts were patent. CONCLUSIONS: Coronary bypass on the beating heart without interruption of coronary flow is feasible. In both open- and in closed-chest procedures, the "Octopus" reduced anastomosis site motion to about 1 X 1 mm without adverse consequences.

Internal mammary artery graft for ischemic heart disease. Effect of revascularization on clinical status and survival.

Four hundred consecutive patients, 80 percent of whom had multiple vessel obstruction, received a single internal mammary artery graft (121 patients) alone or combined with vein grafts (279 patients) in 1971 and 1972. Four patients died during or within 30 days of the operation. Sixteen patients had intraoperative infarction; three died. Arteriography was performed postoperatively (mean 12 months) in 254 patients, and 248 of 261 internal mammary artery grafts (95 percent) and 195 of 237 vein grafts (82 percent) were patent. Follow-up was complete (mean interval 38 months); all 80 patients with single vessel disease are alive, and the 3 year survival rate for patients with double and triple vessel disease was 98.7 and 94.4 percent, respectively. Comparison of longevity of 741 patients who had received vein grafts in 1967 to 1970 with that of 400 patients with internal mammary artery grafts (1971 to 1972) indicates greater survival for the recent series (P less than 0.004). Factors responsible for improved survival include (1) reduced operative mortality, (2) fewer intraoperative infarctions, (3) more complete revascularization, and (4) higher patency rate of the internal mammary artery graft.

Preoperative therapy of low-dose aspirin in internal mammary artery bypass operations with and without low-dose aprotinin.

The effect of preoperative low-dose aspirin (1 mg/kg of body weight) and intraoperative low-dose aprotinin (2 million kallikrein inactivator units) treatment on perioperative blood loss and blood requirements in patients who undergo internal mammary artery bypass operations is unknown. Therefore, we retrospectively studied 75 matching patients who underwent internal mammary artery operations, and they were allocated to one of three groups: low-dose aspirin and aprotinin treatment (group 1, n = 25), low-dose aspirin treatment without aprotinin (group 2, n = 25), and neither aspirin nor aprotinin treatment (group 3, n = 25). Although the perioperative blood loss was similar, the blood requirements tended to be higher (p = 0.09) in the patients who were treated with aspirin (group 2) than in the control patients (group 3). When aprotinin was added to the priming solution in patients who were treated with aspirin (group 1), blood loss was significantly lower (p < 0.05) than that of group 2 patients but not of control patients. Blood requirements were significantly lower (p < 0.01) than those of patients in groups 2 and 3. Blood products were needed in 29%, 62%, and 75% of patients in groups 1, 2, and 3, respectively.

Coronary artery bypass grafting without cardiopulmonary bypass using the octopus method: results in the first one hundred patients.

OBJECTIVE: Cardiopulmonary bypass and global cardiac arrest enable safe coronary artery bypass grafting but have adverse effects. In off-pump coronary bypass grafting, invasiveness is reduced, but anastomosis suturing is jeopardized by cardiac motion. Therefore the key to successful off-pump coronary bypass grafting is effective local cardiac wall stabilization. METHODS: We prospectively assessed the safety and efficacy of the Octopus tissue stabilizer (Medtronic, Inc., Minneapolis, Minn.) in the first 100 patients selected for off-pump coronary bypass via full or limited surgical access. To immobilize and expose the coronary artery, two suction paddles (-400 mm Hg), fixed to the operating table-rail by an articulating arm, stabilized the anastomosis site. RESULTS: One hundred forty-one grafts (96% arterial) were used to create 172 anastomoses (17% side-to-side), up to 4 per patient, on average 23 in the full access group (46 patients) and 1.2 in the limited access group (54 patients). Complications included conversion to cardiopulmonary bypass (2%), conversion from limited to full access (3%), myocardial infarction (4%), predischarge coronary reintervention (2%), and late coronary reintervention (1%). Median postoperative length of hospital stay was 4 days (limited access) or 5 days (full access). Rapid recovery allowed 96% of patients to resume social activities within 1 month. At the 6-month angiographic follow-up, 95% of anastomoses was patent. At the 2- to 22-month follow-up (mean, 13 months), 98 patients were in Canadian Cardiovascular Society class I and 2 patients were in class II. CONCLUSION: These results suggest that off-pump coronary artery bypass grafting with the Octopus tissue stabilizer is safe. Early clinical outcome and patency rates warrant a randomized study comparing this methods with conventional coronary bypass grafting.

Brain death-induced alterations in myocardial workload and high-energy phosphates: a phosphorus 31 magnetic resonance spectroscopy study in the cat.

BACKGROUND: Hemodynamic deterioration resulting from brain death-induced myocardial left ventricular dysfunction may preclude heart donation. A reduced myocardial high-energy phosphate content, assessed by biopsy specimens, has been suggested to be responsible for this phenomenon. By applying phosphorus 31 magnetic resonance spectroscopy, in vivo myocardial high-energy phosphate metabolism can be studied continuously. METHODS: Twelve cats were sedated, intubated, ventilated, and studied for 240 minutes. Heart rate, arterial blood pressure, and arterial blood gases were monitored. Central venous pressure was kept constant. Myocardial work was expressed as rate-pressure product (RPP=heart rate x systolic arterial blood pressure). After sternotomy a radio frequency surface coil was positioned onto the left ventricle. A parietal trephine hole was drilled, and an inflatable balloon was inserted. The animal was placed into a 4.7 T horizontal 40 cm bore magnet interfaced to a spectrometer. Brain death (n=6) was induced by rapid inflation of the balloon; the six other cats served as a sham-operated control group. 31P spectra were obtained in 30 seconds, with ventilation and arterial blood pressure curve triggering. The phosphocreatine/to/adenosine triphosphate ratio, as an estimator of energy metabolism, was calculated. RESULTS: Brain death was established within 30 seconds after inflation of the balloon. Changes in RPP were characterized by a triphasic profile with a maximum increase from 19.3+/-1.4 x 10(3) to 87.5+/-8.1 x 10(3) mm Hg x min(-1) (p < .0001 vs control group) at 2 minutes after inflation of the balloon. Subsequently, RPP decreased and was normalized at 15 minutes after inflation. The third phase was characterized by hemodynamic deterioration, which became significant at 180 minutes and resulted in mean arterial pressure of 71+/-12 mm Hg (p < .05 vs control group) at the end of the experimental period. RPP deteriorated to 14.6+/-2.0 x 10(3) mm Hg x min(-1) (p < .05 vs control group) at 240 minutes. Because the heart rate remained constant during the third phase, the decrease in RPP was caused by a decrease in systolic arterial blood pressure. The initial phosphocreatine/adenosine triphosphate ratio of 1.65+/-0.16 varied to 1.52+/-0.06 at 2 minutes, and to 1.73 +/-0.17 (all values NS vs control group and vs initial ratio) at 240 minutes. CONCLUSIONS: The energy status of the heart is not affected by brain death. Therefore brain death-induced hemodynamic deterioration is not caused by impaired myocardial high-energy phosphate metabolism.

Brain death-related energetic failure of the donor heart becomes apparent only during storage and reperfusion: an ex vivo phosphorus-31 magnetic resonance spectroscopy study on the feline heart.

BACKGROUND AND OBJECTIVE: Recently, we have shown, by using localized in vivo phosphorus-31 magnetic resonance spectroscopy (31P MRS) of the anterior left ventricular wall, that brain death (BD) is not associated with reduced myocardial energy status. In this study, we applied ex vivo 31P MRS of the entire heart to study the effects of BD on the energy status of the feline donor heart following explantation. METHODS: We used cats (6 BD and 6 controls [C]) in a 26-hour protocol. After 2 hours of preparation, we induced BD by filling an intracranial balloon at t = 0 hour. At t = 6 hours, the hearts were arrested with St. Thomas' Hospital cardioplegic solution, explanted, and stored in the same solution at 4 degrees C in a 4.7 Tesla magnet for 17 hours. Subsequently, the hearts were reperfused in the Langendorff mode at 38 degrees C for 1 hour. The first 5-minute 31P MRS spectrum was obtained 1 hour after crossclamping the aorta; we obtained subsequent spectra every hour during storage and every 5 minutes during reperfusion. At the end, the hearts were dried and weighed. Phosphocreatine (PCr), gamma-adenosine triphosphate (gamma-ATP), inorganic phosphate (Pi), and phosphomonoesters (PME), were expressed per g dry heart weight. The intracellular pH (pH(i)) and the PCr/ATP ratio were calculated. RESULTS: During storage, we identified a significant but similar decrease of pH(i), PCr/ATP ratio, and PCr in both groups. During reperfusion, pH(i) and PCr/ATP ratio recovered similarly in both groups, whereas the recovery of PCr in the BD group was significantly lower (p < 0.05). The Pi and PME increased in both groups during storage but to a lesser extent in the BD group (p < 0.05). This difference disappeared during reperfusion. The gamma-ATP was already significantly lower in the BD group at the onset of storage, and this remained so throughout storage and reperfusion (p < 0.05 vs C). Contractile capacity was lost in all hearts, except for 1 heart in the BD group. CONCLUSION: Brain death-related failure of the energetic integrity of the feline donor heart becomes apparent only when using 31P MRS during ischemic preservation and subsequent reperfusion.

Bio-energetic response of the heart to dopamine following brain death-related reduced myocardial workload: a phosphorus-31 magnetic resonance spectroscopy study in the cat.

OBJECTIVE: Long-term exposure of the donor heart to high dosages of dopamine in the treatment of brain death-related hemodynamic deterioration has been shown to reduce myocardial phosphocreatine (PCr) and adenosine triphosphate (ATP) in myocardial biopsy specimens and may preclude heart donation for transplantation. Short-term exposure to the acute catecholamine release during the onset of brain death has shown an unchanged PCr/ATP ratio using in vivo phosphorus-31 magnetic resonance spectroscopy (31P MRS). In this study 31P MRS was used to evaluate in vivo myocardial energy metabolism during long-term dopamine treatment. METHODS: Twelve cats were studied in a 4.7 Tesla magnet for 360 minutes. At t = 0 minutes, brain death was induced (n = 6). At 210 minutes, when myocardial workload in the brain-death group was reduced significantly, dopamine was infused (n = 12) at 5 microg/kg/min and its dose was consecutively doubled every 30 minutes and was withheld during the last 30 minutes of the experiment. Phosphorus-31 magnetic resonance spectra were obtained from the left ventricular wall during 5-minute time frames, and PCr/ATP ratios were calculated. The hearts were histologically examined. RESULTS: Although significant changes in myocardial workload were observed after the induction of brain death and during support and withdrawal of dopamine in both groups, the initial PCr/ATP ratio of 2.00+/-0.12 and the contents of PCr and ATP did not vary significantly. Histologically identified sub-endocardial hemorrhage was observed in 3 of 6 of the brain-dead animals and in 1 of 6 of the control animals. CONCLUSIONS: High dosages of dopamine in the treatment of brain death-related reduced myocardial workload do not alter PCr/ATP ratios and the contents of PCr and ATP of the potential donor heart despite histologic damage.

Minimally invasive coronary artery bypass grafting: on the beating heart and via limited access.

Minimally invasive coronary artery bypass grafting (MICABG) may be achieved by arterial grafting on the beating heart, without cardiopulmonary bypass, and by operations via limited access. The Second Utrecht MICABG Workshop held October 4-5, 1996, focused on beating-heart coronary immobilization, limited-access thoracoscopic and direct-vision mobilization of the internal mammary artery, limited-access left anterior descending coronary artery grafting, and, finally, facilitated distal anastomosis techniques. It has yielded 33 reports in this supplement. The combined, cumulative experience of a number of participants exceeded 3,000 beating-heart cases, including more than 1,000 with arterial grafting through limited access. The average number of anastomoses per patient ranged from 1.0 to 2.0. Therapeutic strategies are evolving, and dedicated instrumentation is being developed. Randomized clinical trials with angiographic follow-up are required to establish that the reduction in invasiveness of coronary bypass grafting is not achieved at the expense of suboptimal quality of the arterial graft and the distal anastomosis.

Intraoperative predonation contributes to blood saving.

The merits of reinfusing prebypass-removed autologous blood (intraoperative predonation) to salvage blood and improve postoperative hemostasis are still debated, specifically for patients at a higher risk for bleeding. To evaluate the effect of intraoperative predonation on the platelet count, blood hemoglobin content, and blood saving postoperatively, we retrospectively studied 100 matching patients. All patients underwent internal mammary artery bypass surgery resulting in a considerable blood loss postoperatively. Intraoperative predonation (800 ml), reinfusion of the residual volume of the extracorporeal circuit, autotransfusion of shed blood, and acceptance of normovolemic anemia postoperatively was the approach adopted in 50 patients (group 1). A similar blood salvage program, excluding intraoperative predonation, was carried out in the other 50 patients (group 2), and these served as the control group. The platelet counts and blood hemoglobin content were significantly higher postoperatively (p < 0.01) in the predonated patients than in the control patients. However, the net blood loss, the amount of retransfused shed blood, and the blood requirements postoperatively were significantly less (p < 0.01) in the predonated patients than in the control patients, whereas 65% of the predonated patients versus 10% of the control patients did not need any donor blood products. In conclusion, predonation reduces the postoperative blood loss and thereby importantly ameliorates the blood-saving effect of a blood salvage program after IMA procedures.

Facilitated exposure of the internal mammary artery in minimally invasive direct-vision CABG.

A method is described to facilitate harvesting of the mammary artery in minimally invasive direct-vision coronary artery bypass grafting using a 10-cm anterior thoracotomy. Hoisting of the anterior thoracic wall with a modified retractor allows good exposure. Harvesting the mammary artery without the use of endoscopic tools was successful in all 10 cases.

Off-pump coronary bypass grafting: how to use the Octopus Tissue Stabilizer.

Off-pump coronary artery bypass grafting requires immobilization of the coronary artery. A suction device (Octopus Tissue Stabilizer), attached to the epicardium and connected rigidly to the operating table rail, was used through limited and full surgical access for single-vessel and multivessel arterial revascularization, respectively. An outline for its application, as used by us to construct 122 anastomoses in 70 patients, including posterior wall grafting (in 9 patients) and sequential grafting on the anterior wall (in 17 patients), is presented.

Similar hospital morbidity with the use of one or two internal thoracic arteries.

The hospital morbidity and mortality of 100 patients operated with two internal thoracic arteries with or without additional vein grafts (BITA group) were compared with a matched group of 100 patients operated with one left internal thoracic artery (ITA) on the anterior descending artery with additional vein grafts (LITA control group). In each study group, 3% of the patients had diabetes mellitus. There was no statistical significant difference in hospital mortality (1% versus 0%), perioperative myocardial infarction (5% versus 1%), low cardiac output (3% versus 5%), rethoracotomy (1% versus 0%), lung complications (13% versus 13%), wound complications (8% versus 8%), other cardiac complications (26% versus 16%), other noncardiac complications (1% versus 4%), median duration of stay in the intensive care unit (1 versus 1 day), and mean duration of stay in the hospital (10.4 versus 10.8 days) between the groups. Logistic regression analysis showed that the number of ITAs used was not a predictor of complications. Thus, there is no difference between the BITA and LITA control group in hospital mortality and morbidity (in patients with a low incidence of diabetes). If an improvement in cardiac event-free and reoperation-free survival is to be expected, the use of both ITAs can be continued in similar patients.

Systemic blood activation during and after autotransfusion.

To evaluate the extent of shed blood activation in two autotransfusion systems and the effect of circulating blood activation upon autotransfusion, we performed a prospective study in 18 patients undergoing internal mammary artery bypass operation and a control group of 10 patients. The autotransfusion systems were from Sorin (n = 9) consisting of a hard shell reservoir with a filter having a small contact area (0.32 m2), and from Dideco (n = 9) consisting of a hard shell reservoir with a filter having a larger contact area (4.64 m2). We found high concentrations of thromboxane, fibrinogen degradation products, complement split product C3a, and elastase in the shed blood and, with the exception of C3a, in the circulating blood of autotransfused patients. There was no such activation in control patients. The degree of the systemic inflammatory reaction was determined by the type of autotransfusion system and by the amount of infused shed blood. The Dideco system provoked more inflammatory response than did the Sorin. This was reflected by the larger shed blood loss during autotransfusion in the Dideco patients than in Sorin patients, resulting in infusion of more shed blood (means, 737 mL versus 566 mL; not significant). After autotransfusion, Dideco patients shed significantly more blood than did Sorin or control patients (p < 0.05). Dideco patients also needed more colloid/crystalloid solution per 24 hours than Sorin patients (p < 0.05). This became clinically relevant only after infusion of more than 800 mL of shed blood (p < 0.001): hemodilution indicated the need for packed cells in 4 Dideco patients and in 1 Sorin patient.(ABSTRACT TRUNCATED AT 250 WORDS)

Low-dose aprotinin in internal mammary artery bypass operations contributes to important blood saving.

The effect on postoperative blood loss and blood use of blood-saving treatment with or without 280 mg of low-dose aprotinin (2 million kallikrein inactivator units) was studied in 200 consecutive patients undergoing either unilateral or bilateral internal mammary artery bypass grafting. Postoperative blood loss and total units of homologous blood products were similar in patients having either bypass procedure without aprotinin treatment. In patients given aprotinin, postoperative blood loss and use of homologous blood products were significantly lower (p < 0.05). The use of any donor blood product was prevented in 78% of the patients given aprotinin versus only 45% of patients treated without aprotinin. None of the aprotinin-treated patients underwent repeat thoracotomy for excessive bleeding; repeat thoracotomy was indicated in 8% of the patients having bilateral internal mammary artery grafting without aprotinin treatment. These results demonstrate that low-dose aprotinin reduces blood loss and blood use significantly and prevents excessive bleeding.

Does it make sense to use two internal thoracic arteries?

Retrospectively, the first 143 patients who were operated on with bilateral internal thoracic arteries (BITA group) were matched with 143 patients operated on with only one left internal thoracic artery anastomosed on the left anterior descending artery and additional vein grafts (LITA group) and followed up for a maximum of 8 years. At 5 years follow-up there were no significant differences in event-free survival between the groups. After 8 years, the overall survival was 96% and 92% (not significant [NS]), cardiac survival 99% and 97% (NS), angina-free cardiac survival 51% and 35% (NS), infarction-free cardiac survival 95% and 78% (NS), reintervention-free cardiac survival 87% and 88% (NS), and all cardiac event-free survival 49% and 31% (NS) for the BITA and LITA groups, respectively. The incidence of late pulmonary, wound, and other complications was comparable. Cox proportional hazards analysis showed that a higher left ventricular end-diastolic pressure and female sex were predictors of recurrent angina and late cardiac events. During this intermediate-term follow-up, the use of one or two internal thoracic arteries was of no value in predicting angina-free or cardiac event-free survival.

Mitral valve repair-related hemolysis: a report of two cases.

Two patients are described who suffered from progressive intravascular hemolysis following different kinds of reconstructive surgery of the mitral valve. Within the context of increasing numbers of operations aimed to preserve the mitral valve, the importance and difficulty of prompt recognition and adequate treatment of this very uncommon but potential lethal complication are emphasised.

Less invasive off-pump CABG using a suction device for immobilization: the 'Octopus' method.

OBJECTIVE: Target site immobilization is essential to enable meticulous anastomosis suturing during coronary artery bypass grafting on the beating heart. A novel device ('Octopus') was developed for local heart muscle immobilization by suction. The purpose of this study was to investigate the efficacy of the method through a limited access. METHODS: The suction device, placed on either side of the recipient coronary artery and fixed to the operating table-rail through an arm construction, restrains anastomosis site motion to 1 x 1 mm. A total of 27 patients underwent off-pump arterial bypass grafting using this method. Preoperatively, all patients had angina class III (NYHA) and were failed or unsuitable candidates for balloon angioplasty. Surgical access was via a 10-cm anterior thoracotomy (n = 26) or 10-cm subxiphoid incision (n = 1). RESULTS: Harvesting of the graft required 48 +/- 12 min (mean +/- S.D.). Immobilization with the 'Octopus' was effective and facilitated precise anastomosis suturing of 20 single and 7 sequential grafts. Immobilization did not change cardiac index and mean arterial blood pressure. During coronary surgery, however, inotropic drug support was used in 5 of 27 (18%) of patients. There was no myocardial infarction. Only minor transient complications were met. There were electro-cardiographical signs of pericarditis in 6 patients. The postoperative hospital stay ranged from 2 to 6 days, mean 4.0 +/- 1.2 days. The mean follow-up is 6.5 +/- 4 months (range, 1-12 months). All patients except one were in functional class I without angina. Social activities were resumed within 4 weeks. At 6 months angiography was performed in 15 out of 27 patients. The patency rate of 19 out of 20 anastomoses was 95%. All distal grafts were patent. One side to side anastomosis was occluded. CONCLUSIONS: The 'Octopus' immobilization method is safe and effective. It facilitates less invasive CABG in selected patients and gives way to fast recovery by reducing invasiveness.

Biventricular pacing in end-stage heart failure improves functional capacity and left ventricular function.

BACKGROUND: Asynchronous patterns of contraction and relaxation may contribute to hemodynamic and functional impairment in heart failure. In 1993, we introduced biventricular pacing as a novel method to treat heart failure by synchronous stimulation of the right and left ventricles after an appropriate atrioventricular delay. The objectives of this study were to assess the early and long-term effects of this therapy on functional capacity and left ventricular function in patients with severe heart failure and left bundle branch block. METHODS AND RESULTS: Twelve patients with end-stage congestive heart failure, sinus rhythm and complete left bundle branch block were treated with biventricular stimulation at optimized atrioventricular delay. The NYHA functional class and maximal bicycle exercise capacity were assessed. Systolic and diastolic left ventricular function were studied with echocardiography and radionuclide angiography. Data was collected at various intervals during 1-year follow-up. Cumulative survival [95% CI] was 66.7% [40.0,93.4] at 1 year and 50 % [21.8, 78.2] at 2 and 3 years. Median NYHA class improved from class IV to class II at 1 year (p=0.008). After 6 weeks an increase in exercise capacity occurred, which was sustained. A less restrictive left ventricular filling pattern, an increase in dP/dt and left ventricular ejection fraction, and a decrease in mitral regurgitation were observed early and long-term. CONCLUSIONS: Biventricular pacing at optimized atrioventricular delay results in improvement in functional capacity, which is associated with improved systolic and diastolic left ventricular function, and a decrease in mitral regurgitation during short- and long-term follow-up.

Efficacy and safety of a blood conservation program including low-dose aprotinin in routine myocardial revascularization.

OBJECTIVES: We attempted to analyze the efficacy and safety of an extensive blood saving program applied in a large cohort of patients. MEASURES: Blood saving included reinfusion of intraoperative predonated blood, aprotinin (2 million KIU) in the prime solution, reinfusion of any residual volume, postoperative acceptance of normovolemic anemia (hematocrit > or = 25%) and autotransfusion of shed blood. SETTING, EXPERIMENTAL DESIGN AND PATIENTS: In our general hospital with a heart surgery service (1150 cases/year), we studied the records of 527 non-selected consecutive patients, who were prospectively treated with this program being applied in primary myocardial revascularization between. RESULTS: We avoided the use of donor blood in 86.9% of the patients requiring a mean of 0.2+/-0.01 unit of donor blood per patient. No repeat thoracotomy for bleeding was needed in any patient. Univariate analysis revealed that female gender, a low level of hematocrit, high age, a small stature, weight, body surface area, and red cell volume prebypass significantly (p<0.001) were correlated to treatment with donor blood. Multiple regression showed that a small red cell volume and a low prebypass hematocrit were the most (p<0.0001) significant predictors for the use of donor blood. Observing a low incidence of morbidity (myocardial infarction, gastrointestinal, neurological thromboembolic, renal and wound complications), the safety of this program seems to be emphasized. CONCLUSIONS: Extensive blood saving including low-dose aprotinin reduced effectively and safely the need for donor blood in a large cohort of patients.

No evidence for participation of non-adrenergic non-cholinergic subtances in brain death-related hemodynamic deterioration of the feline potential heart donor.

OBJECTIVE: To onset of brain death (BD) is associated with a hyperdynamic cardiovascular response caused by the acute sympathetic release of catecholamines. This is followed by progressive hemodynamic deterioration which may preclude heart donation for transplantation. The mechanism of the hemodynamic collapse is not fully understood. Changes in plasma concentrations of non-adrenergic non-cholinergic (NANC) substances, neuropeptide-Y (NP-Y, a vasoconstrictor) and the vasodilators calcitonin gene-related peptide (CGRP) and substance P (SP), were studied in relation to BD-related hemodynamic alterations. MATERIALS AND METHODS: Cats (6 BD and 6 controls (C)) were studied for 6 h. Heart rate (HR) and mean arterial pressure (MAP) were monitored. BD was induced at t = O min. At t = -5, 15, 60, 180 and 360 min, 5 ml arterial blood samples were taken. The plasma was collected and analyzed. The correlations between MAP and NANC levels were calculated. RESULTS: In the BD cats a maximal and significant increase in HR and MAP was observed at t = 2 min. HR returned to basal levels at t = 20 min and remained at that level. However, MAP deteriorated progressively to 53 +/- 8 mmHg (p 0.001 vs C) at/ = 360 min. NP-Y had increased from 59.7 +/- 2.5 to 110 +/- 20.2 pmol/l (p 0.05 vs C) at t = 15 min, had returned to basal value at t = 60 min and remained at that level. CGRP levels were lower and SP levels did not change vs C but both showed a trend towards higher levels at t = 360 min. The correlations between MAP and NP-Y, CGRP and SP appeared to be not significant. CONCLUSION: No evidence for participation of NANC substances could be demonstrated in brain death-related hemodynamic deterioration of the feline potential heart donor.