[Clinical usefulness of transesophageal echocardiography in heart surgery complications]. / Utilità clinica dell'ecocardiografia transesofagea nelle complicanze della chirurgia cardiaca.

The role of monoplane transesophageal echocardiography (TEE) in rapid decision making process was investigated in 115 critically ill patients (pts) with early postoperative complications after cardio-thoracic surgery (hypotension, central venous pressure and/or wedge pressure elevation, electrocardiographic S-T segment elevation). Systolic and diastolic function of left ventricle, left ventricular wall motion abnormalities, right ventricular function, valves or prosthetic valves function, left ventricular outflow tract and morphologic changes were evaluated. Echocardiographic diagnoses were classified as: useful, incomplete, not diagnostic, misleading, unexpected. Echocardiographic diagnoses were confirmed by surgical or pathologic findings in all patients operated or dead. All but one patients, who needed surgical therapy, were operated on the basis of echo-diagnosis alone. Therapeutic changes induced by echo-diagnosis were evaluated and classified as major and minor. Diagnosis was fast (7 +/- 2 m) and sure (no complication). TEE was useful in 91% of cases (105/115 pts), incomplete in 2.3% (3/115 pts), not diagnostic in 2.3% (3/115 pts) and misleading in 3.4% of cases (4/115 pts). TEE findings made major therapeutic changes necessary in 66.9% (77/115 pts); there was a shift from medical to surgical therapy in 28% (41/115 pts); in 14.7% (17/115 pts) minor changes in drug therapy were made. TEE was also useful in quick and safe placement of devices (Swan-Ganz catheter, intra aortic balloon pump, endocardial pace maker, ventricular assist device) and in guiding urgent pericardiocentesis. The effects of medical therapy and evolution of ventricular dysfunction were well monitored by TEE. In our experience TEE was a very useful tool for management of early complications after cardio-thoracic surgery.

[Hemodynamic effects of propofol in patients undergoing pulmonary excision and in patients undergoing closed heart mitral valve surgery]. / Effetti emodinamici del propofol in pazienti operati di exeresi polmonare e in pazienti operati di commissurolisi mitralica a cuore chiuso.

The effects of propofol on cardiovascular dynamics were studied, by means of SO2 Swan-Ganz catheter, in 12 patients scheduled for elective pulmonary resection and in 10 patients undergoing closed heart mitral valve commissurotomy. Myocardial contractility was also investigated in 10 patients (5 pulmonary and 5 mitral valve patients) by means of transthoracic echocardiography. The patients were premedicated with morphine (0.1 mg/kg i.m.), scopolamine (0.005 mg/kg i.m.) and diazepam (0.1 mg/kg p.o.). Anaesthesia was induced with propofol (2 mg/kg i.v.) and fentanyl (0.005 mg/kg i.v.) and maintained with propofol (6 mg/kg/h) plus fentanyl (0.005 mg/kg/h) infusion. Muscle relaxation was assured by pancuronium bromide (0.1 mg/kg). Ventilation (O2-N2O 50%) was controlled to maintain ETCO2 between 30 and 40 mmHg. All the patients undergoing pulmonary resection were intubated with double lumen endotracheal tube. Measurements were performed with the patients awake, after induction, during steady state anaesthesia, before and after thoracotomy. Propofol together with fentanyl significantly decreased arterial pressure (more than 35%) and cardiac index (more than 40%) in both groups of patients; heart rate showed no significant changes even after intubation. Right atrial pressure didn't change meanwhile wedge pressure showed a reduction, with statistical significance only in pulmonary patients. Total systemic resistances didn't show any variation in both groups of patients. The echocardiographic data revealed an important impairment of myocardial contractility after bolus of propofol, mainly in cardiac patients, as evidenced by decrease of ejection fraction values (20%) and by increase of left ventricle end systolic volume index (10%) from baseline. SVO2 and DO2/VO2 ratio values were stable, according with deep anaesthesia level and adequate metabolic balance. In pulmonary patients, during one lung ventilation, the intrapulmonary shunt values did not differed either during or without propofol infusion, thus suggesting that propofol doesn't interfere with pulmonary hypoxic vasoconstrictor response. In conclusion an aware use of propofol and a careful haemodynamic monitoring would be advisable primarily in patients with a well known or supposed cardiovascular disease.

Direct measurement of pulmonary and systemic flow during assisted circulation.

During biventricular assistance as a bridge to cardiac transplantation, the flow data provided by the pumping systems were compared with flow data obtained with the Fick method. There was a difference between the data sets only in the first 20 hr of observation, with the Fick method giving higher values. During the same period, analysis of the arterial and pulmonary pressure traces showed pulsatile activity to be related with the electrocardiogram's T waves. In the long run, the flow data provided by both methods were no different and the T wave-related pulsatile activity disappeared. The authors concluded that the Fick method represents a useful tool when measuring total flow during biventricular support.

Emergency laser vaporization and helium-oxygen administration for acute malignant tracheobronchial obstruction.

Two patients with malignant airway obstruction and acute respiratory insufficiency were given emergency treatment with yttrium aluminum garnet (YAG) laser tissue vaporization under local anesthesia only. A mixture of oxygen and helium was administered to reduce the respiratory distress. This case emphasizes the rapidity and effectiveness of YAG laser treatment via fiberoptic bronchoscopy under local anesthesia in the management of acute malignant airway obstructions.

A prospective study of the clinical benefits of prostacyclin in 554 cardiopulmonary bypass procedures.

Abnormal bleeding after cardiopulmonary bypass (CPB) may result from incomplete neutralization of heparin, increased fibrinolytic activity, consumption of coagulation factors, or from a reduction in the number of circulating platelets together with impairment of platelet function. Although researchers have reason to believe that hemostasis after CPB could be improved with prostacyclin (PGI(2)), a potent inhibitor of platelet aggregation, the drug's clear-cut benefits in this respect have not yet been confirmed. After conducting an initial study concerning the fate of platelets during CPB, in which we determined that PGI(2) had a protective effect, we investigated the effects of PGI(2) infusion during CPB on postoperative blood loss in 554 open-heart surgery patients, 200 of whom underwent valve replacement, 200 of whom had coronary artery bypass grafting (CABG), and 154 of whom underwent repeat valve replacement or CABG. The patients were divided into 2 groups: 277 patients (the study group) received both heparin and PGI(2) during CPB, whereas the remaining 277 patients (the control group) were given heparin alone. Of the patients who underwent surgery for the first time, those treated with PGI(2) had a reduced mean blood loss (p < 0.05 only in CABG patients) in comparison with those who received heparin alone. Of the patients who underwent redo operations, those who received PGI(2) had a nonsignificant tendency toward reduced blood loss. The mean difference in blood loss between the study group and the control group had no clinical relevance, however, because it was less than the smallest practical unit of measurement (i.e., 1 unit of blood).