Perioperative management of left ventricular assist devices.

The use of mechanical circulatory support for patients with severe heart failure is on the rist. The poeoperative, intraoperative and postoperative challenges the anaesthesiologists skills. These are discussed in this review

Antegrade versus antegrade with retrograde delivery of cardioplegic solution in myocardial revascularisation. A clinical study in patients with triple vessel coronary artery disease.

The effects of antegrade and antegrade with retrograde delivery of cardioplegic solution were evaluated in 60 patients who underwent myocardial revascularisation. All patients had triple vessel coronary artery disease and underwent revascularisation using arterial and vein grafts. Myocardial protection consisted of administration of the St.Thomas' Hospital cardioplegic solution, topical slushed ice and systemic hypothermia (28 degrees C-30 degrees C). The patients were categorised into: group A (n=30), who received antegrade cardioplegia alone, and group B (n=30), who received antegrade and retrograde cardioplegia. With the exception of the total dose of cardioplegic solution ('p'=0.02), there was no significant difference between the two groups. Cardiac function was assessed before and after the patient was weaned from the cardio-pulmonary bypass. There was a significant increase in the right atrial pressure and a significant decrease in the mean arterial pressure from the baseline ('p'<0.05), 10 minutes after cardiopulmonary bypass in group A. All patients in-group B had a spontaneous return to sinus rhythm after release of the aortic cross clamp, whereas 3 patients in group A required defibrillation to restore sinus rhythm. Intra aortic balloon pump support was necessary in 4 patients in group A, as against 1 patient in group B to terminate the cardiopulmonary bypass. The clinical outcome was similar in both groups. We conclude that the use of a combination of retrograde and antegrade cardioplegia facilitates early recovery of left ventricular function after coronary artery bypass grafting.

Use of Arginine Vasopressin in the Management of Vasodilatory Shock After CABG - A Clinical Tria.

Vasodilatory shock requiring treatment with catecholamines occurs in some patients following cardiopulmonary bypass. We investigated the use of vasopressin in the treatment of this syndrome. Forty patients with a left main coronary artery disease and a poor left ventricular function (ejection fraction <30%) were studied. Only those patients (n=12, 30%) in whom difficulty was experienced in maintaining a mean arterial pressure of > 60 mm Hg and a systemic vascular resistance of greater than 900 dynes.sec.cm5 on maximal doses of pharmacological and mechanical support were selected. Patients underwent a standard cardiac anaesthesia protocol. All patients had a Swan-ganz catheter inserted pre-operatively. Arginine vasopressin was administered as a bolus of 0.015 units/kg intravenously followed by an infusion of 0.03 units/kg/hour. This dose increased the mean arterial pressure from 67+/-7 to 95+/-5 mm Hg and the systemic vascular resistance from 860+/-55 to 1502+/-71 dynes.sec.cm-5. It was also associated with a decrease in pharmacological support. All subjects responded to vasopressin administration. Vasopressin is an effective pressor in vasodilatory shock after cardiopulmonary bypass.