The effects of metabolic acidosis and alkalosis on the response to sympathomimetic drugs in dogs.

Sympathomimetic drugs are commonly used in many circumstances to increase cardiac output, blood pressure, and myocardial contractility. However, factors such as acidosis or alkalosis are known to influence the action of these drugs. This study looked at the response to the administration of epinephrine, norepinephrine, dopamine, dobutamine, isoproterenol, and glucagon at normal pH and under acidotic (pH 7.

Comparative hemodynamic effects of propofol and thiamylal sodium during anesthetic induction for myocardial revascularization.

The safety and efficacy of propofol, a new intravenous anesthetic agent, have been demonstrated in healthy patients. Twenty-one patients, ASA III-IV, undergoing elective myocardial revascularization, were randomly chosen to receive either propofol, 2.5 mg/kg, or thiamylal, 4 mg/kg.

Shivering following cardiac surgery: hemodynamic changes and reversal.

The effects of shivering on hemodynamics and systemic oxygenation, as well as the effectiveness of therapeutic interventions in decreasing shivering and increasing mixed venous oxygen saturation, were studied. Thirty adult patients undergoing cardiopulmonary bypass with systemic hypothermia were observed for 1 1/2 to 5 hours postoperatively for signs of shivering associated with a simultaneous decrease in oxygen transport. Systemic and pulmonary hemodynamic measurements were made, blood temperature and mixed venous oxygen saturation were monitored via the pulmonary arterial catheter, and oxygen consumption and delivery were calculated.

Verapamil and myocardial preservation in patients undergoing coronary artery bypass surgery.

The value of verapamil hydrochloride as a myocardial preservative when administered prior to or during periods of myocardial ischemia was studied in patients with normal preoperative cardiac function during elective coronary artery bypass grafting. Myocardial protection included systemic hypothermia (28 degrees C) and hypothermic hyperkalemic cardioplegia. Patients were randomly divided into four groups.

Rate of protamine administration: its effect on heparin reversal and antithrombin recovery after coronary artery surgery.

Patients received a calculated dose of protamine at two different rates (5 min and 30 min) after coronary artery surgery to determine the relationship of the rate of protamine administration with the adequacy of heparin reversal and the rate of return of antithrombin III (AT III) activity. Plasma heparin concentrations and AT III activities were measured at specific times both during and for 3 days after cardiac surgery. Both rates of protamine administration resulted in clinically acceptable clotting, return of the activated coagulation time to normal, and zero heparin concentration after 24 hr.

Hemodynamics of intravenous nitroglycerin during aortic clamping.

Anesthetic management and dosage schedules of vasodilators have not been standardized in many studies of aortic cross clamping (CCL). For this reason, 25 consecutive patients with arteriosclerotic disease of the aorta were studied, all having received the same anesthetic management. Six patients who received nitroglycerin during the cross clamp period, at a dosage of 0.

Anesthetic technic using profound hypothermia for correction of congenital heart defects in infants and small children.

Profound hypothermia can be a useful adjunct in the intraoperative management of infants and small children undergoing surgical correction of congenital heart defects. A case description of a 5 1/2-month-old male infant with total anomalous pulmonary venous drainage who had successful repair using surface cooling, cardiopulmonary bypass, and pump cooling to 20 C with intermittent periods of low systemic blood flow illustrates the technic. Discussed are the value of surface cooling before cooling on cardiopulmonary bypass, physiologic changes affecting the intraoperative and postoperative course, and the major risks and advantages of the technic.

Successful use of a reduced dose of protamine after cardiopulmonary bypass.

The dose of protamine necessary to reverse heparin was examined in 60 patients. Half the patients (controls) received a reversal dose of protamine equal to the entire amount of heparin given them, while half received a reversal dose based on a heparin half-life of 2 hours. Postoperative chest drainage for the first 12 hours and for 48 hours was markedly reduced in patients given the reduced dose of protamine.