Intraoperative cell salvage is associated with reduced postoperative blood loss and transfusion requirements in cardiac surgery: a cohort study.

BACKGROUND: This study investigated whether implementation of cell salvage of shed mediastinal and residual blood in all patients undergoing low-to-moderate-risk cardiac surgery reduces the need for allogeneic red blood cell (RBC) transfusion compared to patients not subjected to cell salvage. STUDY DESIGN AND METHODS: This retrospective cohort study included patients undergoing low-to-moderate-risk cardiac surgery with cardiopulmonary bypass without (control; n = 531) or with cell salvage (n = 433; Autolog, Medtronic). Study endpoints, including 24-hour blood loss and RBC requirements, were evaluated using adjusted logistic regression. RESULTS: Baseline characteristics were similar between groups. The cell saver group received 568 ± 267 mL of autologous blood. Median number of allogeneic RBC transfusions was higher in the control group (2 [1-5]) compared with the cell salvage group (1 [0-3]; p < 0.001). There were no clinically relevant differences in postoperative coagulation test results between groups. The relative risk (RR) for postoperative RBC transfusion was reduced to 0.76 (95% confidence interval [CI], 0.70-0.83; p < 0.0001) in the cell salvage group. Moreover, patients in the cell salvage group had a lower chance for myocardial infarction (RR, 0.26; 95% CI, 0.08-0.91; p = 0.035), whereas the cell salvage group was associated with a higher probability for intensive care discharge within 24 hours after surgery (RR, 1.08; 95% CI, 1.02-1.14; p = 0.009). CONCLUSION: The use of cell salvage throughout the entire procedure reduces postoperative blood loss and allogeneic RBC transfusion. These findings advocate implementation of cell salvage in all patients undergoing on-pump cardiac surgery, irrespective of anticipated surgery-related blood loss.

Residual blood processing by centrifugation, cell salvage or ultrafiltration in cardiac surgery: effects on clinical hemostatic and ex-vivo rheological parameters.

The study compared the effects of three blood concentration techniques after cardiopulmonary bypass on clinical hemostatic and ex-vivo rheological parameters. Residual blood of patients undergoing elective cardiac surgery was processed by centrifugation, cell salvage or ultrafiltration, and retransfused (n = 17 per group). Study parameters included blood loss, (free) hemoglobin, hematocrit, fibrinogen and erythrocyte aggregation, deformability and 2,3-diphosphoglycerate content. Patient characteristics were similar between groups. Ultrafiltration was associated with the highest weight of the transfusion bag [649 ± 261 vs. 320 ± 134 g (centrifugation) and 391 ± 158 g (cell salvage); P < 0.01]. Cell salvage resulted in the lowest hemolysis levels in the transfusion bag. Retransfusion of cell saver blood induced the largest gain in postoperative patient hemoglobin levels when compared to centrifugation and ultrafiltration, and was associated with the largest increase in 2,3-diphosphoglycerate when compared to ultrafiltration (Δ2,3-diphosphoglycerate 1.34 ± 1.92 vs. -0.77 ± 1.56 mmol/l; P = 0.03). Cell salvage is superior with respect to postoperative hemoglobin gain and washout of free hemoglobin when compared to centrifugation or ultrafiltration.

Contrast-enhanced ultrasound for myocardial perfusion imaging.

Ultrasound contrast agents are gas-filled microbubbles that enhance visualization of cardiac structures, function and blood flow during contrast-enhanced ultrasound (CEUS). An interesting cardiovascular application of CEUS is myocardial contrast echocardiography, which allows real-time myocardial perfusion imaging. The intraoperative use of this technically challenging imaging method is limited at present, although several studies have examined its clinical utility during cardiac surgery in the past. In the present review we provide general information on the basic principles of CEUS and discuss the methodology and technical aspects of myocardial perfusion imaging.

Transurethral resection syndrome detected and managed using transesophageal Doppler.

Transurethral resection syndrome during transurethral resection of the prostate (TURP) results from excessive absorption of electrolyte-free irrigation fluids causing acute hypervolemia and hyponatremia. Neuraxial anesthesia is often recommended for TURP procedures because early signs of neurological deterioration can be detected. However, in patients requiring general anesthesia, other continuous and noninvasive measures are needed. Acute intravascular hypervolemia should be reflected by changes in hemodynamic values. Transesophageal Doppler ultrasonography of the aorta allows determination of stroke volume and other advanced hemodynamic variables related to intravascular volume status. We describe the first case of intraoperative detection of a TURP syndrome by noninvasive Doppler monitoring of hemodynamic variables during TURP.

H9c2 cardiomyoblasts produce thyroid hormone.

Thyroid hormone acts on a wide range of tissues. In the cardiovascular system, thyroid hormone is an important regulator of cardiac function and cardiovascular hemodynamics. Although some early reports in the literature suggested an unknown extrathyroidal source of thyroid hormone, it is currently thought to be produced exclusively in the thyroid gland, a highly specialized organ with the sole function of generating, storing, and secreting thyroid hormone. Whereas most of the proteins necessary for thyroid hormone synthesis are thought to be expressed exclusively in the thyroid gland, we now have found evidence that all of these proteins, i.e., thyroglobulin, DUOX1, DUOX2, the sodium-iodide symporter, pendrin, thyroid peroxidase, and thyroid-stimulating hormone receptor, are also expressed in cardiomyocytes. Furthermore, we found thyroglobulin to be transiently upregulated in an in vitro model of ischemia. When performing these experiments in the presence of 125 I, we found that 125 I was integrated into thyroglobulin and that under ischemia-like conditions the radioactive signal in thyroglobulin was reduced. Concomitantly we observed an increase of intracellularly produced, 125 I-labeled thyroid hormone. In conclusion, our findings demonstrate for the first time that cardiomyocytes produce thyroid hormone in a manner adapted to the cell's environment.