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Cerebral Oxygen Desaturation Predicts Cognitive Decline and Longer Hospital Stay After Cardiac Surgery

BACKGROUND Previous studies have reported an 11% to 75% incidence of postoperative cognitive decline among cardiac surgery patients. The INVOS Cerebral Oximeter (Somanetics Corp, Troy, MI) is a Food and Drug Administration approved device that measures regional cerebral oxygen (rSo(2)) saturation. The purpose of this study is to examine whether decreased rSo(2) predicts cognitive decline and prolonged hospital stay after coronary artery bypass grafting (CABG). METHODS The rSo(2) was monitored intraoperatively in a cohort of primary CABG patients. Patients were prospectively randomized to a blinded control group or an unblinded intervention group. Cognitive function was assessed preoperatively, postoperatively, and at 3 months using a battery of standardized neurocognitive tests. Cognitive decline was defined as a decrease of one standard deviation or more in performance on at least one neurocognitive measure. The rSo(2) desaturation score was calculated by multiplying rSo(2) below 50% by time (seconds). Multivariate logistic regression models were used to assess cognitive decline and hospital stay. The change in cognitive performance was also assessed using a multivariate linear regression model. RESULTS Patients with rSo(2) desaturation score greater than 3,000%-second had a significantly higher risk of early postoperative cognitive decline [p = 0.024]. Patients with rSo(2) desaturation score greater than 3,000%-second also had a near threefold increased risk of prolonged hospital stay (>6 days) [p = 0.007]. CONCLUSIONS Intraoperative cerebral oxygen desaturation is significantly associated with an increased risk of cognitive decline and prolonged hospital stay after CABG.

Ventricular-Assist Pumping in Patients with Cardiogenic Shock after Cardiac Operations

A ventricular-assist pump was used to support the circulation in eight patients who could not be separated from cardiopulmonary bypass after open-heart operations. In five patients with left ventricular failure, the systemic circulation was maintained with pumping from the left atrium to the aorta for 7.0 +/- 1.8 days (mean +/- S.E.M.); three of these patients were well four to 17 months after surgery. In two patients with biventricular failure, right and left ventricular bypass supported the circulation, but neither patient survived. One other patient had isolated right ventricular failure; pumping from the right atrium to the pulmonary artery maintained the pulmonary circulation for 2.2 days. This patient lived for 18 months. Use of the ventricular-assist pump in our patients provided complete support of the systemic or pulmonary circulation or both. Profoundly depressed ventricular function is potentially reversible if technical problems in employing the pump can be avoided.

Hetastarch as a Prime for Cardiopulmonary Bypass

Hetastarch, a synthetic colloid osmotic plasma volume expander, was employed in a prime for cardiopulmonary bypass in 37 patients undergoing myocardial revascularization. Comparison of laboratory values to those of 42 patients undergoing myocardial revascularization using an albumin-containing prime showed lower postoperative platelet counts (p less than 0.02) with hetastarch. There were no differences in chest tube drainage, blood use, plasma hemoglobin, fibrinogen levels, of coagulation times. The hetastarch prime cost

Obstruction of the True Lumen during Retrograde Perfusion of Type I Aortic Dissections: A Simplified Solution

119.50 per patient, whereas the albumin-containing prime cost

Anomalous Mitral Arcade: Echocardiographic and Angiographic Recognition

321.35 per patient.

Resistance differences between blood and crystalloid cardioplegic solutions with myocardial cooling

Retrograde perfusion of the false lumen in cases of type I dissection of the thoracic aorta may not permit reperfusion of the coronary arteries when the aortic cross-clamp is removed. We have employed a Y connector between the coronary perfusion outlet of the oxygenator and cardioplegia delivery system. This allows reperfusion of the coronary arteries through the ascending aortic graft. As cardiopulmonary bypass is discontinued, the true aortic lumen is reexpanded and the false lumen collapsed by forward flow of blood from the heart. The successful use of this system is described.

Utilization and Cost Effectiveness of Computerized Patient Data Management in the Multispecialty Intensive Care Unit

SummaryA patient with sudden onset of hemiplegia was noted to have an anomalous mitral arcade at cardiac surgery. Echocardiographic and angiographic data are correlated with the anatomic findings. The clinical significance of this anomaly is discussed.

Surgical Repair of Dissection of the Upper Descending Thoracic Aorta and Discrete Ascending Aortic Aneurysm

Abstract The effectiveness of a cardioplegic solution is dependent on maintaining adequate myocardial perfusion as the heart is cooled. Due to dissimilar rheological properties of blood (BC) and crystalloid (CC) cardioplegic solutions, differences in coronary vascular resistance (CVR) would be expected to develop during postarrest, hypothermic perfusion. To characterize rheologic differences between hypothermic BC and CC, we measured the viscosity of both solutions at 5°C intervals from 30 to 10°C with a Brookfield concentric cylinder viscometer. To evaluate hypothermic changes in CVR, we measured myocardial temperature, perfusion pressure, and perfusate flow during the injection of BC at 10°C in five dogs and CC at 10°C in five dogs. CVR was calculated from simultaneous, postarrest pressure and flow measurements taken at 5°C intervals from 30 to 15°C. The viscosity of BC increased from 1.72 ± 0.25 cP at 30°C to 2.67 cP at 10°C, while the viscosity of CC increased from 0.94 ± 0.02 to 1.44 ± 0.02 cP over the same temperature range. For BC, CVR increased from 0.134 ± 0.035 mm Hg·ml −1 ·min at 30°C to 0.199 ± 0.069 mm Hg·ml −1 ·min at 15°C, while CVR for CC increased from 0.0972 ± 0.024 to 0.111 ± 0.020 Hg·ml −1 ·min at 15°C. Two-way analysis of variance demonstrated that viscosity ( F = 48.5, P = 0.0001) and CVR ( F = 5.82, P = 0.042) were greater for BC than CC. Decreasing temperature resulted in significant differences in viscosity ( F = 347.3, P = 0.0001) and CVR ( F = 11.45, P = 0.0001) for the cardioplegic solutions. We have demonstrated that myocardial cooling results in a more pronounced increase in CVR for BC than for CC which can, in part, be attributed to differences in viscosity. As a consequence, BC will require a perfusion pressure higher than that of CC to maintain coronary flow with decreasing myocardial temperature.

Right ventricular failure after repair of left ventricular aneurysm.

Computerization of intensive care units has proven effective in specialized intensive care units such as shock/trauma units,1 cardiovascular surgical intensive care units,2 coronary care units,3 neonatal intensive care units,4 and units managed by intensivists.5 Greenberg, Civetta, and Barnhill5 have shown that in such units the per-patient requirements of nursing time can be decreased with the use of a computer.

Successful management of right ventricular failure with the ventricular assist pump following aortic valve replacement and coronary bypass grafting

This report describes successful staged surgical repair in 2 patients with dissection of the upper descending thoracic aorta (DeBakey type III) with coexisting discrete Marfans aneurysms of the ascending aorta. Initial repair of the descending aortic dissection was done through a left thoracotomy using a transverse aorta--femoral artery shunt in 1 patient and a left ventricular apex--femoral artery shunt without systemic heparinization in the other. Emphasis is placed on the need for pharmacological reduction of blood pressure during aortic cross-clamping as well as the use of a shunt to prevent dissection of the ascending aortic aneurysm. In both patients, subsequent repair of the ascending aortic aneurysm was accomplished using composite graft replacement of the aortic valve and ascending aorta. This operation is advised for such patients even in the absence of notable aortic valve incompetence.