14 research outputs found
A modified Ross operation to prevent pulmonary autograft dilatation.
A modification in Ross operation is described in which the free-standing pulmonary autograft root is suspended in a Dacron prosthetic vascular jacket with a view to prevent dilatation of the neo-aortic root. In a group of 13 patients operated consecutively using this technique, there was no significant increase in the diameters of the neo-aortic root after a mean 16-month follow-up. Aortic valve function remained also satisfactory
The modified Ross operation using a Dacron prosthetic vascular jacket does prevent pulmonary autograft dilatation at 4.5-year follow-up.
Objective: Following the Ross operation, pulmonary autografts tend to dilate over time. This study researches the fate of the pulmonary autograft - at 4.5 years following the modified Ross operation - with special reference to the impact of the modification on (a) pulmonary autograft dilatation, (b) the neo-aortic root geometry, (c) neo-aortic valve function and (d) the coronary artery reserve. Methods: A total of 26 patients who underwent the Ross operation were included in this study; of these, 13 consecutive patients underwent a modified Ross operation in which the free-standing autograft root was supported externally by a Dacron vascular prosthetic jacket (DVPJ). These patients were compared to a cohort of 13 matched patients who were operated on using the conventional Ross technique; all patients were followed up prospectively by echocardiography studies. The patients who underwent the modified Ross operation were also subjected to bicycle ergometry. Results: At the 47-month median follow-up, there was no significant increase in the size of the entire neo-aortic root in the patients who underwent the modified Ross operation; in addition, the geometry of the neo-aortic root was also preserved and the left ventricular function had improved significantly, whilst the aortic valve function and excursion remained satisfactory. All patients, with one exception, in the modified Ross operation group exhibited normal exercise capacity. By contrast, there were significant differences in diameters of the aortic root - between the two surgical techniques in favour of the modified Ross technique - following a median follow-up of 23 months in the patients subjected to the conventional Ross operation. Conclusions: Provision of external support to the entire pulmonary autograft with a DVPJ prevents its dilatation following free-standing pulmonary autograft Ross operation when evaluated at the 4.5-year follow-up. The function and the geometry of the neo-aortic root are not affected negatively by this modification and the patients demonstrated normal exercise capacity
Risks Associated With the Transfusion of Various Blood Products in Aortic Valve Replacement.
Patients undergoing cardiac operations often require transfusions of red blood cells, plasma, and platelets. From a statistical point of view, there is a significant collinearity between the components, but they differ in indications for use and composition. This study explores the relationship between the transfusion of different blood components and long-term mortality in patients undergoing aortic valve replacement alone or combined with revascularization
A new de-airing technique that reduces systemic microemboli during open surgery: a prospective controlled study.
OBJECTIVE: We have evaluated a new technique of cardiac de-airing that is aimed at a) minimizing air from entering into the pulmonary veins by opening both pleurae and allowing lungs to collapse and b) flushing out residual air from the lungs by staged cardiac filling and lung ventilation. These air emboli are usually trapped in the pulmonary veins and may lead to ventricular dysfunction, life-threatening arrhythmias, and transient or permanent neurologic deficits. METHODS: Twenty patients undergoing elective true left open surgery were prospectively and alternately enrolled in the study to the conventional de-airing technique (pleural cavities unopened, dead space ventilation during cardiopulmonary bypass [control group]) and the new de-airing technique (pleural cavities open, ventilator disconnected during cardiopulmonary bypass, staged perfusion, and ventilation of lungs during de-airing [study group]). Transesophageal echocardiography and transcranial Doppler continually monitored the air emboli during the de-airing period and for 10 minutes after termination of the cardiopulmonary bypass. RESULTS: The amount of air embolism as observed on echocardiography and the number of microembolic signals as recorded by transcranial Doppler were significantly less in the study group during the de-airing time (P < .001) and the first 10 minutes after termination of cardiopulmonary bypass (P < .001). Further, the de-airing time was significantly shorter in the study group (10 vs 17 minutes, P < .001). CONCLUSION: The de-airing technique evaluated in this study is simple, reproducible, controlled, safe, and effective. Moreover, it is cost-effective because the de-airing time is short and no extra expenses are involved
Systemic effects of carbon dioxide insufflation technique for de-airing in left-sided cardiac surgery.
OBJECTIVE: Systemic effects of carbon dioxide (CO(2)) insufflation during left-sided cardiac surgery were evaluated in a prospective randomized study, with regard to acid-base status, gas exchange, cerebral hemodynamics, and red blood cell morphology. METHODS: Twenty patients undergoing elective left-sided cardiac surgery were randomized to de-airing procedure either by CO(2) insufflation technique (CO(2) group, n = 10) or by Lund technique without CO(2) insufflation (Lund group, n = 10). Groups underwent assessment of acid-base status by intermittent arterial blood gases and in-line blood gas monitoring. Capnography was used to determine volume of CO(2) produced. Cerebral hemodynamics was measured by transcranial Doppler sonography and near-infrared spectroscopy. Red cell morphology from cardiotomy suction and vent tubing was studied by scanning electron microscopy. RESULTS: Patients in the CO(2) group consequently developed significantly higher levels of hypercapnia with a concomitant increase in the volume of CO(2) produced despite significantly higher oxygenator gas flows compared with the Lund group. Effects on cerebral hemodynamics were observed in the CO(2) group with significantly higher blood flow velocities in the middle cerebral artery and higher regional cerebral saturation. Red blood cell damage was observed in the CO(2) group by scanning electron microscopy (97% in CO(2) group vs 18% in Lund group). CONCLUSIONS: Insufflation of CO(2) into the cardiothoracic wound cavity during left-sided cardiac surgery can induce hypercapnic acidosis and increased cerebral blood flow and local blood cell damage. These systemic effects should be monitored by in-line capnography and acid-base measurements for early and effective correction by increase in gas flows to the oxygenator