Differences in platelet growth factor release and leucocyte kinetics during autologous platelet gel formation.

Three commercial systems for whole blood separation were compared to obtain the buffy coat composed of platelet-rich plasma (BC-PRP) and leucocytes . These samples of the buffy coat were used to make a platelet gel (PG), which was used to measure platelet growth factor (PGF) release, to perform a white blood cell (WBC) count and to measure myeloperoxidase (MPO) release from WBCs. Aliquots of whole blood obtained from ten volunteers were distributed either to a blood cell separator (The Electa Cell-Separator, E-CS) or to a tabletop centrifuge (Gravitational Platelet Sequestration System, GPS) to prepare the BC-PRP. The third system combines the BC-PRP production by E-CS with a micro porous filter (Autologous Growth Factor filter, AGF) to enrich for the BC-PRP. Autologous thrombin was used to activate the BC-PRP and to prepare the PG and subsequently to degranulate the platelet concentrate. Platelet-derived growth factor-AB and transforming growth factor-beta1 were present in high levels after thrombin activation of the E-CS or GPS prepared samples. However, the AGF prepared samples released their growth factors before thrombin activation. The WBCs were significantly increased with each of the three systems. Contrary to the AGF, no leucocyte degranulation occurred with the E-CS or GPS prepared samples, based upon the low MPO concentrations in the BC-PRP. The three types of apparatus had different harvesting capacities for collecting the enriched platelets and the release of high concentrations of PGF. When the E-CS and GPS, but not the AGF, were used, low levels of MPO were maintained in the PG, which potentially contributes to antimicrobial properties of platelet gel at the site of application.

Trillium-coated oxygenators in adult open-heart surgery: a prospective randomized trial.

This randomized, prospective clinical trial examines the impact of the use of Trillium biopassive surface coating on clinical outcomes after cardiopulmonary bypass (CPB) that may be induced by contact of blood elements with foreign surfaces. The study consisted of 98 consecutive patients randomly assigned to either a CPB circuit that consisted of a Trillium-coated Affinity open reservoir oxygenator or a CPB circuit with an uncoated Affinity open reservoir oxygenator. The operative procedure performed on all 98 patients consisted of either coronary artery bypass graft (CABG), valve, or a combination of the two. Exclusion criteria consisted of patients who presented to the operating room in circulatory arrest. Trillium biopassive surface coating resulted in improved clinical outcomes and fewer adverse events when compared to the control group. Significantly, fewer patients required no blood products (18.3% in the control group vs. 32.7% in the treatment group), even though the control group had a significantly higher pre-bypass hematocrit. Postoperative atrial fibrillation (24.5% vs. 16.3%) and reoperation for bleeding (10.2% vs. 4.1%) showed a much lower incidence in the Trillium group. Significance was not reached because of the small sample size resulting in low power. Trillium circuits result in improved patient outcomes in the treatment group when compared to the control circuit group.

Blood product use during routine open heart surgery: the impact of the centrifugal pump.

A prospective randomized study was done including 1,000 patients undergoing routine open heart surgery. Patients were randomly assigned to either a roller pump or a BioMedicus centrifugal pump with identical extracorporeal circuits. There were no significant differences between study groups. Actual blood products transfused and predicted transfusion requirements (using Cardiac RiskMaster) were examined as was chest tube drainage (CTD). The predicted transfusion requirement was 885 of 1,000 patients. Transfusions were required by 472 of 1,000. Risk factors as significant predictors of increased CTD and use of blood products were emergency surgery status, increased cross-clamp time, and higher predicted risk of mortality. The only significant predictor of decreased CTD was the use of a centrifugal pump. Predictors of increased length of stay were myocardial infarction, preoperative urea, age, and massive transfusion. Data provide evidence that use of the centrifugal pump improves patient outcomes by decreasing CTD and decreasing the requirements for transfusion, which results in a shorter hospital stay.

Maintaining intraoperative normothermia: a meta-analysis of outcomes with costs.

The present study used a meta-analysis to examine 4 questions about intraoperative hypothermia. The questions addressed were as follows: (1) Is the difference in adverse patient outcomes between normothermic and mildly hypothermic patient groups significant across studies and within studies? (2) What is the magnitude of the difference in adverse patient outcomes across studies? (3) What are the costs resulting from the difference in adverse patient outcomes? (4) Does a significant difference exist in effectiveness of modality for maintaining intraoperative normothermia? The results of this meta-analytic study provide evidence that the difference in adverse patient outcomes between the normothermic and mildly hypothermic patients is significant across studies for all adverse outcomes examined. The magnitude of this difference and the costs resulting from these adverse outcomes are presented. In addition, a significant difference in effectiveness between warming modalities for maintaining intraoperative normothermia was found. A significant increase in the risk of costly complications occurred when patient temperatures dropped a mean of 1.5 degrees C. For example, patients who become mildly hypothermic are much more likely to receive blood transfusions and to develop infections; both of these outcomes result in increased costs. Minimizing adverse outcomes is critical to cost-effective patient care in today's competitive healthcare environment. The cost of preventing intraoperative hypothermia is much less than the cost of treating the adverse outcomes that affect patients experiencing intraoperative hypothermia. Meta-analytic results allowed us to conclude that hypothermia averaging only 1.5 degrees C less than normal resulted in cumulative adverse outcomes adding between $2,500 and $7,000 per surgical patient to hospitalization costs across a variety of surgical procedures. In conclusion, patients whose temperatures have been maintained at normal levels during the intraoperative period experience fewer adverse outcomes, and their overall hospital costs are lower. Intraoperative normothermia is maintained more effectively with the use of forced air warming.

Transfusion after coronary artery bypass surgery: the impact of heparin-bonded circuits.

OBJECTIVE: To identify the impact of heparin bonded (Carmeda) circuits on the need for transfusion of packed red blood cells (PRBC) after CABG independent of the influence of patient, procedural, and surgical experience variables. METHODS: A prospective, randomized trial examined the impact of heparin-bonded circuits in 210 patients undergoing coronary artery bypass surgery at Medical Center of Delaware (Christiana Care Health Services). Patients were randomized to either non-bonded circuits or heparin-bonded (Carmeda) circuits. There were no significant differences in patient characteristics between the treatment and control group. A multivariate analysis was performed to identify the independent predictors of both the need for transfusion (logistic) and number of units of PRBC transfused (OLS). RESULTS: The only significant (P < 0.05) independent predictors of need for transfusion were gender (odds ratio (OR) = 0.35 for males), use of anticoagulants prior to surgery (OR = 2.09), cross-clamp time (OR = 1.03 for each extra minute), and use of heparin-bonded circuits (OR = 0.50 for patients in the heparin-bonded; Carmeda, circuit group). The only significant independent predictors of number of PRBCs were anticoagulants prior to surgery, cross-clamp time, catheterization procedure on the same day, body surface area, and use of heparin-bonded circuits. Other patient demographic variables, comorbidities, and surgical variables were not significant independent predictors of the need for transfusion or the number of units transfused. CONCLUSIONS: Several factors influence the probability of transfusion that patients face following coronary artery bypass surgery. The probability of transfusion is 50% less and the number of PRBCs transfused are 1.42 units less when heparin-bonded (Carmeda) circuits are used, adjusted for patient demographics, comorbidities, or surgical variables.

Twenty-year, three-institution evaluation of the Hancock Modified Orifice aortic valve durability. Comparison of actual and actuarial estimates.

BACKGROUND: Information regarding the incidence of structural valve deterioration (SVD) is used in selecting the type of valve for patients. Standard actuarial statistical techniques have been used widely but do not provide the most appropriate information for patient populations experiencing competing hazards. "Actual," or cumulative incidence, methods may provide a better estimate of the durability of tissue valves for these patients. The purpose of this article is to compare actuarial and actual estimates of the durability of the Hancock Modified Orifice bioprosthesis aortic valve in a multi-institutional study. METHODS AND RESULTS: Valves were implanted between 1976 and 1985 in 3 institutions. This sample contains follow-up data on 727 patients (42% female) with a mean age of 63 +/- 13 years. The difference between actuarial and actual rates of SVD became more important over time. At 5 years, the difference is significant only in the elderly (aged > or = 65 and > or = 70), whereas at 17 years, the difference was significant for all patients. Similarly, the magnitude of the difference increases over time. Freedom from SVD for patients > 65 at 5 years is estimated at 98 +/- 0.01% by actuarial methods and 100 +/- 0.00% actual methods. The difference between estimates is larger at 10 years, 93 +/- 0.02% versus 96 +/- 0.01%. This difference is greater at 17 years, 78 +/- 0.04% versus 93 +/- 0.01%. CONCLUSIONS: The results of this study demonstrate that the particular statistical analysis method used to calculate SVD can provide strikingly different conclusions. These observations indicate that the actual method is able to identify the lower risk of SVD in older patients. Generalizability issues must be considered, however, when using actual SVD rates to make decisions regarding valve selection in larger populations.

Heparin-bonded circuits: clinical outcomes and costs.

The aim of this study was to use meta-analysis to combine the results of numerous studies and examine the impact of heparin-bonded circuits on clinical outcomes and the resulting costs. Heparin-bonded circuits, both ionically and covalently bonded, are examined separately. The results of the study provide evidence that heparin-bonded circuits result in improved clinical outcomes when compared to the identical nonheparin-bonded circuits. These improved clinical outcomes result in subsequent lower costs per patient with their use. However, differences are apparent in the significance and magnitude of these outcomes between ionically and covalently bonded circuits. Covalently bonded circuits provide a greater magnitude and significance of improvement in clinical outcomes than ionically bonded circuits. Total cost savings can be expected to be three times greater with covalently bonded circuits ($3231 versus $1068). It was concluded that the choice regarding the use of a heparin-bonded circuits and the type of heparin-bonded circuit used has the potential to alter clinical outcomes and subsequent costs. Cost consideration cannot be ignored, but clinical benefits should be the main rationale for the choice of cardiopulmonary bypass circuit. This analysis provides evidence that clinical benefits and cost savings can both be derived from use of the same technology-covalently bonded circuits.

Platelet-rich plasmapheresis: a meta-analysis of clinical outcomes and costs.

Platelet-rich plasmapheresis (PRP) just prior to cardiopulmonary bypass (CPB) surgery is used to improve post CPB hemostasis and to minimize the risks associated with exposure to allogeneic blood and its components. Meta-analysis examines evidence of PRP's impact on clinical outcomes by integrating the results across published research studies. Data on clinical outcomes was collected from 20 published studies. These outcomes, DRG payment rates, and current national average costs were used to examine the impact of PRP on costs. This study provides evidence that the use of PRP results in improved clinical outcomes when compared to the identical control groups not receiving PRP. These improved clinical outcomes result in subsequent lower costs per patient in the PRP groups. All clinical outcomes analyzed were improved: blood product usage, length of stay, intensive care stay, time to extubation, incidence of cardiovascular accident, and incidence of reoperation. The most striking differences occur in use of all blood products, particularly packed red blood cells. This study provides an example of how initial expenditure on technology used during CPB results in overall cost savings. Estimated cost savings range from $2,505.00 to $4,209.00. More importantly, patients benefit from improved clinical outcomes.

Health care of Holsteins selected for large or small body size.

Genetic groups of Holsteins selected for large size or small size were compared for health care needs. Two groups were formed from a paired foundation population. Large group was mated to sires with extreme estimates of transmitting ability for tall height and deep and wide bodies. Small group was similarly mated to extreme sires but to those transmitting short height and shallow and narrow bodies. Predicted Differences for milk and fat of sires were above breed average. Actual expenses for veterinary treatment, health supplies and drugs, and value of labor required of animal attendants were evaluated. Large cows required significantly more health care than small cows. Digestive disorders accounted for much of the group difference, and displaced abomasums were more frequent among large cows. Small cows may have economic advantages over large cows of the same breed.