The Journal of thoracic and cardiovascular surgery
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J. Thorac. Cardiovasc. Surg. · Nov 1979
Plasma vasopressin levels and urinary flow during cardiopulmonary bypass in patients with valvular heart disease: effect of pulsatile flow.
The effect of pulsatile flow on plasma vasopressin levels during cardiopulmonary bypass (CPB) was studied in 20 patients undergoing open valve replacement. Routine bypass was used in 10 patients and the AVCO pulsatile bypass pump was utilized in the other 10. In Group I (nonpulsatile) during CPB, the vasopressin level was markedly elevated (3.1 +/- 2 to 80 +/- 22 pg/ml) as was urine flow (0.6 +/- 0.2 to 5.9 +/- 2 ml/min) and urine Na+ concentration (69 +/- 19 to 116 +/- 7 mEq/L). ⋯ These data suggest that CPB produces a marked vasopressin stress response which is beyond the physiological range for an antidiuretic effect on the kidney. At these levels vasopressin can exert a vasopressor effect to maintain resistance and affect renal blood flow, as well as producing an Na+ diuresis. The addition of pulsatile flow creates a more physiological situation attenuating the vasopressin response and producing a decrease in systemic resistance and a less pronounced Na+ diuresis.
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J. Thorac. Cardiovasc. Surg. · Jul 1979
Heparin administration during extracorporeal circulation: heparin rebound and postoperative bleeding.
The individual variations in heparin dose response and heparin activity decay have indicated limitations of the protocols based on body surface area and weight of the patients. In the present study the heparin levels and simpler clotting tests were monitored in a consecutive series of 71 patients undergoing standard cardiac operations. The clotting tests used were the Celite activated clotting time (Celite ACT) and the whole blood activated recalcification time (BART). ⋯ A significant difference was seen in the measured heparin levels (p less than 0.01, Celite ACT (p less than 0.01), and BART (p less than 0.01) in patients on Protocols I and II. Ten of the 24 patients on Protocol I and none on Protocol II showed heparin rebound phenomenon, and blood loss in patients on Protocol I was significantly greater than that in patients on Protocol II. The study clearly demonstrates that our protocol of heparin administration and control with simpler tests ensures safe hypocoagulation during ECC and efficient reversal at the end, with minimal postoperative blood loss.
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J. Thorac. Cardiovasc. Surg. · Jul 1979
Pulmonary artery banding in infants with complete atrioventricular canal.
Management of symptomatic atrioventricular canal (AVC) in infancy may be difficult. Between July, 1969, and September, 1977, 31 infants with complete AVC presented in congestive heart failure (CHF) to the University of Minnesota Hospitals. Fifteen of these patients have responded to medical management and have been followed as outpatients. ⋯ Each of the remaining six patients, who have been followed for 9 months to 9 years, had minimal mitral insufficiency and a large ventricular shunt. The three patients dying after banding had significant mitral insufficiency. We believe that pulmonary artery banding is an effective palliative procedure for infants with complete AVC and CHF who have large ventricular shunts and minimal mitral insufficiency.
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J. Thorac. Cardiovasc. Surg. · May 1979
Case ReportsRunaway pump head: new cause of gas embolism during cardiopulmonary bypass.
Massive gas embolism was narrowly avoided during a recent case of cardiopulmonary bypass for aortic valve replacement. Cause of the mishap was an arterial pump head that had rapidly accelerated spontaneously, emptying the oxygenator of blood within seconds. No gas entered the patient's vascular system, but a period of circulatory arrest was required in order to purge the extracorporeal circuit of gas and to re-establish blood flow. Only an instantaneous response by the perfusionist prevented massive gas embolism.