Preservation of myocardial energy status by bovine hemoglobin solutions during ischemia.

Compared to murine and human hemoglobin, bovine hemoglobin has a less exothermic oxygen binding and delivers oxygen even at low temperatures. This property could improve oxygen availability for myocytes during hypothermic arrest of hearts. The aim of this study was to evaluate the advantage of using cardioplegic solutions enriched with bovine hemoglobin when storing rat hearts. Hearts excised from rats after perfusion with different cardioplegic solutions (Celsior, Celsior plus 4% human hemoglobin, Celsior plus 4% and 8% bovine hemoglobin) were compared. Biopsies were obtained from the beating hearts before cardioplegic infusion and during a 48 h period of cold storage. Adenosine triphosphate, its catabolites and markers of oxidative stress were measured as indices of preservation. The results show that bovine hemoglobin-enriched solutions highly improve adenosine triphosphate content, decreasing its catabolites; no significant changes in antioxidant status were evident. The statistically significant difference was evident up to 6 h of storage. Doubling the concentration of bovine hemoglobin produces only slight improvement. Alternative hemoglobins with different properties may improve and prolong heart storage. As bovine hemoglobin delivers oxygen even at low temperatures, it improves energy content and anabolic reactions, without decreasing oxidative stress.

Siena's experience with pulmonary autograft operations: clinical and echocardiographic follow-up.

As there is no perfect aortic valve substitute, there is a need to find out which one is the best option to replace the diseased aortic valve. Any type of mechanical or biological stented device has a residual gradient and does not reproduce the extremely sophisticated normal aortic valve function. This may influence the short- and long-term outcome, especially in dilated and poorly contracting left ventricles which do not tolerate even a mild stenosis. Thus, the potentially ideal valve to replace the aortic valve is either an aortic valve (aortic homograft) or a pulmonary autograft in aortic position. These grafts are also less subject to endocarditis. It has been demonstrated that pulmonary autografts can grow when implanted in children and as they remain viable, they maintain their dynamic behavior and possibly the internal innervation of the cusps. Unfortunately, pulmonary autograft surgery is more demanding and lasts longer, which may increase the risk of the operation. In addition, the exact indications and applications of the operation, particularly in patients with poor left ventricles or additional lesions, have not been clearly defined. Here we report our experience with this technique in 11 patients with severe aortic valve disease, including those with poor left ventricle function and/or associated disease. We describe our short- and medium-term follow-up, which shows optimal left ventricle recovery with no perioperative or postoperative complications, thus supporting a wider application of the operation.

[Teicoplanin therapy in neonatal and pediatric intensive therapy]. / La terapia con teicoplanina in terapia intensiva neonatale e pediatrica.

We administered teicoplanin as specific antibiotic therapy for nosocomial "ICU specific" infections with methicillin-resistant Staphylococcus aureus and epidermidis (MRSA-MRSE). The above mentioned drug has been given to 20 patients (15 newborns and 5 not-newborns) admitted into intensive care unit during the years 1988, 1989, 1990 with MRSA-MRSE localized and/or systemic infection, affected by severe disease (RDS, pulmonary edema, congenital cardiac disease, cystic fibrosis) undergoing invasive procedures which presented high nosocomial infective risk (tracheal intubation, mechanical ventilation, venous and arterial cannulation, total parenteral nutrition, etc.). Complete recovery from systemic or localized infection (sepsis, low respiratory tract infection, high respiratory tract infection) occurred in 19 out of 20 patients, with a rate of success of 95%. Teicoplanin treatment lasted from a minimum of nine days to a maximum of thirty days. The dose was 5-6 mg/kg/die in one administration for the first three days, then 4 mg/kg/die. The tolerability of teicoplanin has proven satisfactory, since we had no major side effects during treatment and follow up.