Activation of the alternative pathway of complement during the acute phase of typical haemolytic uraemic syndrome.

Haemolytic uraemic syndrome (HUS) is characterized by haemolytic anaemia, thrombocytopenia and acute renal failure. We studied the activation state of classical and alternative pathways of complement during the acute phase of Shiga toxin-associated HUS by performing a prospective study of 18 patients and 17 age-matched healthy controls to evaluate C3, C3c, C4, C4d, Bb and SC5b-9 levels. SC5b-9 levels were increased significantly in all patients at admission compared to healthy and end-stage renal disease controls, but were significantly higher in patients presenting with oliguria compared to those with preserved diuresis. C3 and C4 levels were elevated significantly at admission in the non-oliguric group when compared to controls. No significant differences were found for C4d values, whereas factor Bb was elevated in all patients and significantly higher in oliguric patients when compared to both controls and non-oliguric individuals. A positive and significant association was detected when Bb formation was plotted as a function of plasma SC5b-9 at admission. Bb levels declined rapidly during the first week, with values not significantly different from controls by days 3 and 5 for non-oligurics and oligurics, respectively. Our data demonstrate the activation of the alternative pathway of complement during the acute phase of Stx-associated HUS. This finding suggests that complement activation may represent an important trigger for the cell damage that occurs during the syndrome.

Isolated and complete traumatic rupture of the pancreas: A case report and a review of the literature.

INTRODUCTION: Pancreatic trauma without injuries to other organs is uncommon, as reported in the reviewed literature. Diagnosis of pancreatic trauma might be difficult, due to unspecific signs and symptoms. The integrity of the main pancreatic duct is the crucial point in the management and outcome of patients with pancreatic trauma. PRESENTATION OF CASE: The authors report a case of delayed diagnosis after a complete traumatic rupture of the main pancreatic duct, successfully managed by surgical treatment. The authors performed a laparotomy with complete removal of necrotic pancreatic tissue at the site of rupture. The proximal pancreatic stump was hand-sewn with detached stitches and a disposable catheter was positioned into Wirsung's duct, a diversion of the distal stump with a Roux-en-y pancreato-jejunal anastomosis was performed. The postoperative course was uneventful. DISCUSSION: Traumatic injuries of the pancreas occur after blunt abdominal traumas or penetrating wounds with a ratio of 3:1. Isolated traumatic injuries of the pancreas are uncommon; and they are usually associated with injuries to other organs. Surgical solutions for the treatment of pancreas lesions vary and it is well known that a surgical procedure performed after a delayed diagnosis is associated with high mortality and morbidity, especially in pancreatic duct rupture. CONCLUSION: Pancreatic trauma is a diagnostic and therapeutic challenge for the trauma surgeon. The integrity of the main pancreatic duct is the most important determinant of outcome after injury to the pancreas and, in Wirsung's duct rupture, early surgery may improve it.

Evaluation of tamoxifen and anastrozole in the prevention of gynecomastia and breast pain induced by bicalutamide monotherapy of prostate cancer.

PURPOSE: To determine whether tamoxifen or anastrozole prevents gynecomastia and breast pain caused by bicalutamide (150 mg) without compromising efficacy, safety, or sexual functioning. PATIENTS AND METHODS: A double-blind, placebo-controlled trial was performed in patients with localized, locally advanced, or biochemically recurrent prostate cancer. Patients (N = 114) were randomly assigned to either bicalutamide (150 mg/d) plus placebo or in combination with tamoxifen (20 mg/d) or anastrozole (1 mg/d) for 48 weeks. Gynecomastia, breast pain, prostate-specific antigen (PSA), sexual functioning, and serum levels of hormones were assessed. RESULTS: Gynecomastia developed in 73% of patients in the bicalutamide group, 10% of patients in the bicalutamide-tamoxifen group, and 51% of patients in the bicalutamide-anastrozole group (P < .001); breast pain developed in 39%, 6%, and 27% of patients, respectively (P = .006). Baseline PSA level decreased by > or = 50% in 97%, 97%, and 83% of patients in the bicalutamide, bicalutamide-tamoxifen, and bicalutamide-anastrozole groups, respectively (P = .07); and adverse events were reported in 37%, 35%, and 69% of patients, respectively (P = .004). There were no major differences among treatments in sexual functioning parameters from baseline to month 6. Elevated testosterone levels occurred in each group; however, free testosterone levels remained unchanged in the bicalutamide-tamoxifen group because of increased sex hormone-binding globulin levels. CONCLUSION: Anastrozole did not significantly reduce the incidence of bicalutamide-induced gynecomastia and breast pain. In contrast, tamoxifen was effective, without increasing adverse events, at least in the short-term follow-up. These data support the need for a larger study to determine any effect on mortality.

Risk factors for early hospital readmission after cardiac operations.

OBJECTIVE: Early hospital readmissions after cardiac procedures are both costly and harmful to patients. We investigated the factors that predispose to readmission to develop strategies to minimize this problem. METHODS: As part of a prospective data collection, patients having cardiac procedures at our institution are routinely tracked for 30 days after their discharge from the hospital. We reviewed 2650 patients in our cardiac database who underwent operations over the past 5 years. We used univariate and multivariate statistical techniques to identify risks for readmission. RESULTS: Of 2574 discharged patients, 252 (9.8%) required readmission. The most common causes of readmission are cardiac (42%), pulmonary (19%), gastrointestinal (10%), extremity complications (6.7%; deep vein thrombophlebitis, peripheral arterial vascular disease, and saphenous vein harvest site problems), sternal wound problems (7.5%), and metabolic problems (4%). Of more than 70 variables studied, only 6 are significant multivariate predictors of readmission: female sex (P =.002); diabetes (P =.001); chronic lung problems (P =.011); increased distance between home and hospital (P >.001); preoperative atrial fibrillation (P =.002); and preoperative chronic renal insufficiency (P =.002). Type of operation, redo procedures, and other intraoperative and postoperative variables are not important multivariate predictors of readmission. Prolonged hospital length of stay for the initial procedure did not cause more frequent readmission. The costs of initial hospitalization (operating room costs combined with postoperative in-hospital costs) were not significantly increased in those patients who required readmission. CONCLUSIONS: The high-risk patient for readmission is a woman with diabetes, chronic lung disease, renal insufficiency, and preoperative atrial fibrillation who lives at a distance from the hospital. Readmission does not depend on periprocedural variables (eg, cardiopulmonary bypass time) or on postoperative complications. High procedural costs from the initial hospitalization do not predispose to readmission. These results suggest interventions that may reduce readmission.

Oropharyngeal dysphagia after cardiac operations.

BACKGROUND: As many as 15% of hospitalized patients have oropharyngeal dysphagia. The incidence and causes of postoperative oropharyngeal dysphagia (OD) in patients having cardiac operations are poorly documented and the best treatment is uncertain. We undertook a study to evaluate OD in patients having cardiac operations. METHODS: As part of a quality improvement project, all patients operated on in 1998 and 1999 were monitored for the signs or symptoms of OD. Patients with OD had diagnostic and therapeutic interventions to limit adverse outcomes. At the end of the 2-year evaluation period, patient risk factors, diagnoses, results of interventions, and outcomes were measured. RESULTS: Thirty-one out of 1,042, patients (3%) had OD. OD is more common in older patients (p < 0.0001) with diabetes (p = 0.02), renal insufficiency (p = 0.012), hyperlipidemia (p = 0.046), and preoperative congestive heart failure (p < 0.0001), and in those having noncoronary artery bypass procedures (p < 0.0001). One patient with OD died from respiratory arrest, presumably secondary to aspiration. Modified barium swallow (MBS) identified oral dysphagia in 2 patients, pharyngeal dysphagia in 7 patients, and both oral and pharyngeal dysphagia in 17 patients. One patient had a structural defect (cervical osteophyte) causing dysphagia and 4 patients had no identifiable cause of dysphagia on MBS. Postoperative neurologic complications are more common in patients with OD. Ten of 31 patients (32%) with OD had some new neurologic complication after operation compared with 36 of 1,011 (3.5%) who had a postoperative neurologic problem without OD. In 19 patients with OD no cause for swallowing difficulty was identified. Specifically, no metabolic, myopathic, or infectious abnormalities were identified in any patient with OD. Hospital charges were significantly increased in patients with OD ($69,320 versus $36,087, p < 0.0001). Therapy consisting of modification of eating behavior and swallowing technique and in some severe cases enteral or parenteral feeding was successful in all patients except 1, but 4 patients required more than 4 months of supportive care before return to oral feeding was possible. CONCLUSIONS: OD is associated with increased cost and morbidity. Older patients with diabetes, preoperative heart failure, and renal insufficiency are at increased risk for OD. Early recognition and intervention is likely to result in satisfactory outcome but may be associated with a protracted postoperative course.

Cost-effectiveness of minimally invasive cardiac operations.

BACKGROUND: Minimally invasive cardiac operations (MICOs) are reported to reduce procedural costs while at the same time decreasing operative morbidity and improving patient comfort. However, most of the cost data available for minimally invasive cardiac procedures is limited to short-term, peri-procedure, in-hospital costs. The scarcity of data to support claims for long-term cost-effectiveness prompted our interest in pursuing this research. METHODS: Cost-effectiveness analysis was used to estimate the monetary cost required to achieve a gain in health benefit. We reviewed the literature to accumulate all available relevant cost data regarding MICO in order to apply the principles of cost-effectiveness analysis to this relatively new procedure. For purposes of the analysis, two assumptions were made: (1) MICOs have a less favorable long-term survival outcome than does conventional coronary artery bypass grafting using cardiopulmonary bypass (CABG), and (2) the reintervention rates and long-term costs resulting from MICOs are similar to those of percutaneous transluminal coronary angioplasty with intracoronary stenting (PTCA/stenting). RESULTS: The average procedural costs from published literature were $13,782 for PTCA/stenting, $16,082 for MICO, and $23,938 for CABG. The cost-effectiveness of CABG and MICO were compared using PTCA/stenting as a standard of comparison. These estimations suggest that MICO is less cost-effective than CABG ($112,200 per year of life saved by MICO and $56,280 per year of life saved by CABG). CONCLUSIONS: Usable data to provide accurate cost-effectiveness estimates for MICO is scarce. Preliminary estimates based on available data suggest two means of improving the cost-effectiveness of MICO. First, technical advances that improve the quality of MICO (e.g., improved patency rates for mammary anastomoses and complete revascularization strategies) will decrease the reintervention rates and out-of-hospital costs. Second, application of MICO to a high-risk subset of patients who will experience improved survival compared to other alternatives will improve cost-effectiveness by prolonging life for those patients. Therefore, in order to be cost-effective, MICOs must obtain high quality results, including complete revascularization, and must be used primarily in high-risk patients.

Long-term angiographic results of coronary endarterectomy.

BACKGROUND: To evaluate the long-term patency of endarterectomized coronary vessels, we studied patients having recatheterization after coronary artery bypass grafting. METHODS: Forty-one clinical and angiographic variables were analyzed in 97 study patients who had coronary endarterectomy (CE) and in 154 control patients who did not have CE but who had repeat catheterization after coronary artery bypass grafting. RESULTS: Ninety-seven patients had 132 CEs. The right coronary artery was the most commonly endarterectomized vessel (73 of the 132 endarterectomized vessels). At a mean of 7.1 years of follow-up, significantly fewer bypass grafts to endarterectomized vessels were patent compared with nonendarterectomized vessels (40% of endarterectomized vessels compared with 58% of nonendarterectomized vessels in study patients and 65% in control patients, p = 0.0003). The only predictor of long-term CE graft patency is age-adjusted body surface area (p = 0.0068). Patency in grafts to nonendarterectomized vessels is diminished by hypertension (p = 0.046) and current cigarette use (p = 0.024) and improved by use of mammary artery grafting (p < 0.0001). CONCLUSIONS: These results show that long-term patency in bypass grafts to endarterectomized vessels is less common than in nonendarterectomized vessels and that this patency is related to larger body size. Patency in nonendarterectomized vessels is reduced by risks of arteriosclerosis. This suggests that CE should be used with caution in smaller patients and that aggressive control of risk factors for atherogenesis is particularly important in patients who have CE. On the basis of these results, we speculate that the extent of disease is advanced in patients who require CE.

Bicalutamide monotherapy versus flutamide plus goserelin in prostate cancer patients: results of an Italian Prostate Cancer Project study.

PURPOSE: To compare the efficacy of bicalutamide monotherapy to maximal androgen blockade (MAB) in the treatment of advanced prostatic cancer. PATIENTS AND METHODS: Previously untreated patients with histologically proven stage C or D disease (American Urological Association Staging System) were randomly allocated to receive either bicalutamide or MAB. After disease progression, patients treated with bicalutamide were assigned to castration. The primary end point for this trial was overall survival. Secondary end points included response to treatment, disease progression, treatment safety, quality-of-life (QOL), and sexual function. RESULTS: A total of 108 patients received bicalutamide and 112 received MAB. There was no difference in the percentage of patients whose prostate-specific antigen returned to normal levels. At the time of the present analysis (median follow-up time, 38 months; range, 1 to 60 months), 129 patients progressed and 89 died. There was no difference in the duration of either progression-free survival or overall survival. However, a survival trend favored bicalutamide in stage C disease but MAB in stage D disease. Overall and subgroup trends were confirmed by multivariate analysis. Serious adverse events and treatment discontinuations were more common in patients receiving MAB (P =.08 and P =.04, respectively). Fewer patients in the bicalutamide group complained of loss of libido (P =. 01) and of erectile dysfunction (P =.002). Significant trends favored bicalutamide-treated patients also with respect to their QOL, namely relative to social functioning, vitality, emotional well-being, and physical capacity. CONCLUSION: Bicalutamide monotherapy yielded comparable results relative to standard treatment with MAB, induced fewer side effects, and produced a better QOL.

[Long-term effects on recurrence and mortality in superficial urothelioma of the bladder treated with endovesical chemotherapy]. / Risultati a lungo termine sulle recidive e mortalità negli uroteliomi superficiali della vescica sottoposti a chemioterapia endovescicale.

BACKGROUND: To evaluate as the natural history of superficial bladder tumors is modified by intravesical chemotherapy and if the behavior of treated tumors allows to forecast subsequent tumoral evolution. METHODS: 125 patients with superficial bladder tumor Ta and T1 were submitted to transurethral resection (TURB) and additional chemotherapy for one year. Mean follow-up was of 92.2 +/- 39.8 months and all patients were observed for four years at least. RESULTS: Efficacy of treatment was according to the literature: the median of recurrence was estimated about the 10th year (increase of free interval); the percentage of patients free from recurrence after 14 years of follow-up was 35 +/- 19.9, instead that of specific survival was 87.1 +/- 11.8 (inefficacy in a long period); the percentage of tumor related deaths was of 10.4 (inefficacy to avoid the progression). Regarding the risk factors present on the beginning, there was a significance for the T1 that relapsed in the 56.6% versus the 30.9% of the Ta (p = 0.012) and for the multiple tumors that relapsed in the 64.4% versus the 38.7% of the single one (p = 0.009). Also the time and the T category of the first recurrence were interesting factors for the subsequent evolution of disease. In fact, in the 47 patients at beginning T1 that relapsed, there was a 43.4% of tumor related deaths if the recurrence occurred in the first year of follow-up, versus the 12.5% if the recurrence occurred after the first year (p = 0.017). Furthermore the 61.9% of patients "non Ta" (T1 or Tis) to the first recurrence died for tumor but no one if the first recurrence was Ta (p = 0.000). CONCLUSIONS: Intravesical chemotherapy is still reliable. It is able to increase the free interval of recurrence after TURB. Moreover it can offer a useful criterion to recognize patients with chemoresistant tumors at higher risk of progression.

Operative outcome and hospital cost.

INTRODUCTION: Because of concern about increasing health care costs, we undertook a study to find patient risk factors associated with increased hospital costs and to evaluate the relationship between increased cost and in-hospital mortality and serious morbidity. METHODS: More than 100 patient variables were screened in 1221 patients undergoing cardiac procedures. Simultaneously, patient hospital costs were computed from the cost-to-charge ratio. Univariate and multivariate statistics were used to explore the relationship between hospital cost and patient outcomes, including operative death, in-hospital morbidity, and length of stay. RESULTS: The greatest costs were for 31 patients who did not survive operation ($74,466, 95% confidence interval $27,102 to $198,025), greater than the costs for 120 patients who had serious, nonfatal morbidity ($60,335, 95% confidence interval $28,381 to $130,897, p = 0.02) and those for 1070 patients who survived operation without complication ($31,459, 95% confidence interval $21,944 to $49,849, p = 0.001). Breakdown of the components of hospital costs in fatalities and in cases with nonfatal complications revealed that the greatest contributions were in anesthesia and operating room costs. Significant (by stepwise linear regression analysis) independent risks for increased hospital cost were as follows (in order of decreasing importance): (1) preoperative congestive heart failure, (2) serum creatinine level greater than 2.5 mg/dl, (3) New York state predicted mortality risk, (4), type of operation (coronary artery bypass grafting, valve, valve plus coronary artery bypass grafting, or other), (5) preoperative hematocrit, (6) need for reoperative procedure, (7) operative priority, and (8) sex. These risks were different than those for in-hospitality death or increased length of stay. Hospital cost correlated with length of stay (r = 0.63, p < 0.001), but there were many outliers at the high end of the hospital cost spectrum. CONCLUSIONS: We conclude that operative death is the most costly outcome; length of stay is an unreliable indicator of hospital cost, especially at the high end of the cost spectrum; risks of increased hospital cost are different than those for perioperative mortality or increased length of stay; and ventricular dysfunction in elderly patients undergoing urgent operations for other than coronary disease is associated with increased cost. Certain patient factors, such as preoperative anemia and congestive heart failure, are amenable to preoperative intervention to reduce costs, and a high-risk patient profile can serve as a target for cost-reduction strategies.

The platelet thrombin receptor and postoperative bleeding.

BACKGROUND: We hypothesized that small amounts of thrombin desensitize the platelet thrombin receptor during cardiopulmonary bypass (CPB), resulting in postoperative platelet dysfunction and bleeding. METHODS: Seventy-nine patients were entered into a study designed to measure changes in platelet thrombin receptor function during CPB and to correlate them to postoperative bleeding. In addition to measurements of clinical blood loss, platelet function tests of aggregation, activation, and cell-cell adhesion were used. The thrombin receptor agonist peptide (TRAP) was used to activate the platelets. Flow cytometry was used to measure various platelet surface markers and platelet-white cell interactions during CPB. RESULTS: Compared with preoperative values, both aggregometry and flow cytometry measured a significant reduction of TRAP-induced activation immediately and up to 24 hours after CPB. The response of other activating agents returned to normal by 24 hours. Postoperatively, 8 of 79 patients required excessive blood transfusion (> or = 10 units of blood products) and had significantly decreased TRAP-induced aggregation response. CONCLUSIONS: Our results show that (1) platelet activation, aggregation, and adhesion to leukocytes induced by TRAP are reduced after CPB, (2) decreased thrombin receptor responsiveness is associated with excessive postoperative blood loss, and (3) because the aggregation and activation responses are different for TRAP and thrombin, there may be a second thrombin receptor on platelets that is protected from damage during CPB. These results imply that prevention of the CPB-induced effects on the thrombin receptor will lessen postoperative morbidity associated with blood transfusion.

The women of Salerno: contribution to the origins of surgery from medieval Italy.

Medicine in medieval Europe benefited from Greek, Arabic, Hebrew, and Latin influences. Because of geographic and other favorable conditions, many of these cultural contributions synergized to form the Medical School at Salerno around 900 AD. Somewhat uncharacteristically, women physicians played a part in the advances that came from this school. Among the contributions associated with the School of Salerno were (1) textbooks of anatomy, obtained mainly from porcine dissections, (2) insistence on certification and training for physicians, (3) application of investigative thinking and deduction that led to important advances such as the use of healing by secondary intention, (4) the first textbook about women's medicine, and (5) the first recorded female medical school faculty member named Trotula de Ruggiero or Trocta Salernitana. The women physicians of Salerno contributed to a textbook that gained wide acceptance and distribution throughout Europe. The textbook, called De Passionibus Mulierium, was first published about 1100 AD and was a prominent text until a significant revision by Ambrose Paré's assistant in the early 1600s. Paré was the preeminent anatomist of his time, and many of his important anatomic and surgical considerations were directly and indirectly derived from the work of the women of Salerno. The advances first recorded, taught, and implemented by the women of Salerno are an interesting and important part of our surgical heritage.

Relaxant effect of human brain natriuretic peptide on human artery and vein tissue.

Brain natriuretic peptide (BNP) is a cardiac-derived peptide hormone with cardiovascular and renal actions that is structurally and functionally related to atrial natriuretic peptide (ANP). Previous studies using rat vascular tissue have demonstrated a direct vasorelaxant effect of BNP. However, species-specific potency issues have precluded an accurate measurement of the effect of human BNP. This report demonstrates the vasorelaxant effects of human BNP on human vascular tissue prepared from internal mammary artery and saphenous vein samples. The vasorelaxant effect of human BNP is compared to the other members of the natriuretic peptide family, human ANP and C-type natriuretic peptide (CNP). With regard to potency and magnitude of effect, human BNP and human ANP were similar in relaxing arterial tissue preconstricted with endothelin-1 (BNP ED50 = 1.9 nmol/L and ANP ED50 = 1.8 nmol/L) or phenylephrine (BNP ED50 = 10 nmol/L and ANP ED50 = 19 nmol/L), while CNP was significantly less effective. All three natriuretic peptides exhibited weak venodilating action. These data demonstrate that human BNP is a potent inhibitor of the vasoconstrictive actions of endothelin-1 and the alpha-adrenergic agonist phenylephrine on isolated human artery tissue preparations.

Risk factors for postoperative morbidity.

OBJECTIVE: Analysis of outcomes after coronary artery bypass grafting has focused on risk factors for operative mortality. Nonfatal perioperative morbidity is far more costly and more common after operation. To identify the risk factors that lead to postoperative morbidity, we evaluated 938 patients undergoing coronary artery bypass grafting at Albany Medical Center Hospital during 1993. METHODS: Multivariate statistical analysis was performed on preoperative patient variables to identify risk factors for either serious postoperative morbidity or increased hospital length of stay. Variables were considered both individually and in combination. For example, age was considered individually or in combination with other variables, including parameters of blood volume (i.e., age divided by red blood cell volume or Age/RBCVOL). Similar multivariate analysis was performed to identify independent risk factors for hospital mortality. RESULTS: In order of decreasing importance, the following patient variables were significantly associated with increased length of stay by stepwise Cox regression analysis: Age/RBCVOL, history of congestive heart failure, hypertension, femoral-popliteal peripheral vascular disease, chronic obstructive lung disease, and renal dysfunction. The combination variable, Age/RBCVOL, was an important risk factor for both increased length of stay and serious postoperative morbidity. Variables that were significant independent predictors of increased mortality, such as preoperative shock, and redo operation, were not risk factors for either serious morbidity or increased length of stay. CONCLUSIONS: We conclude that risk factors for postoperative morbidity are different from those for postoperative mortality. These results suggest that older patients with preoperative anemia and low blood volume who also have other comorbidities (congestive heart failure, stroke, chronic obstructive pulmonary disease, or hypertension) are at increased risk for postoperative complications. This allows identification of a high-risk cohort of patients who are likely candidates for interventions to lessen postoperative morbidity.

Thrombin receptor-related hemostatic defect after cardiopulmonary bypass.

Platelet abnormalities have been blamed for the hemostatic defect that develops after cardiopulmonary bypass (CPB), but investigators have not been able to agree upon an intrinsic platelet abnormality responsible for the observed defect. To better define the blood components responsible for this post-operative hemostatic defect, we compared platelet function in whole blood (WB) to that in platelet-rich plasma (PRP) in 33 patients undergoing coronary artery bypass grafting. We measured platelet aggregation in response to various platelet agonists, including thrombin and TRAP-6 (a 6-amino acid peptide that activates the thrombin "tethered ligand" receptor site). In WB there was a lasting, diminished response to TRAP-6, but not to gamma-thrombin, after CPB. Control experiments showed that this diminished response to TRAP-6: (1) was not related to heparin or heparin-protamine complexes, (2) was not the result of hemodilution during CPB, (3) was not related to increased amounts of naturally occurring enzymes (aminopeptidases) that degrade TRAP, and (4) was not able to be reversed by the addition of as much as a 10-fold excess of the usual TRAP-6 aggregating dose to WB preparations. In contrast, no corresponding defect in platelet aggregation could be identified in PRP obtained from patients after CPB. These results show that, in post-operative blood samples, blood components present in WB and not in PRP (eg, red blood cells, activated white cells or platelets bound to white cells) diminish the ability of TRAP peptides to activate the thrombin receptor but do not decrease the ability of gamma-thrombin to induce platelet aggregation. This suggests that for circulating platelets after CPB: (1) interactions of platelets with other blood cell elements are the cause of altered postoperative platelet reactivity rather than any intrinsic CPB-induced platelet defect, (2) drugs, such as aprotinin, that limit activation of white cells and the fibrinolytic system may also have beneficial effects on platelet function after CPB, and (3) alternate mechanisms exist that allow thrombin, but not TRAP-6, to activate platelets normally after CPB (perhaps a second, as yet undefined, thrombin receptor).

Limiting excessive postoperative blood transfusion after cardiac procedures. A review.

Analysis of blood product use after cardiac operations reveals that a few patients (< or = 20%) consume the majority of blood products (> 80%). The risk factors that predispose a minority of patients to excessive blood use include patient-related factors, transfusion practices, drug-related causes, and procedure-related factors. Multivariate studies suggest that patient age and red blood cell volume are independent patient-related variables that predict excessive blood product transfusion after cardiac procedures. Other factors include preoperative aspirin ingestion, type of operation, over- or underutilization of heparin during cardiopulmonary bypass, failure to correct hypothermia after cardiopulmonary bypass, and physician overtransfusion. A survey of the currently available blood conservation techniques reveals 5 that stand out as reliable methods: 1) high-dose aprotinin therapy, 2) preoperative erythropoietin therapy when time permits adequate dosage before operation, 3) hemodilution by harvest of whole blood immediately before cardiopulmonary bypass, 4) autologous predonation of blood, and 5) salvage of oxygenator blood after cardiopulmonary bypass. Other methods, such as the use of epsilon-aminocaproic acid or desmopressin, cell saving devices, reinfusion of shed mediastinal blood, and hemofiltration have been reported to be less reliable and may even be harmful in some high-risk patients. Consideration of the available data allows formulation of a 4-pronged plan for limiting excessive blood transfusion after surgery: 1) recognize the causes of excessive transfusion, including the importance of red blood cell volume, type of procedure being performed, preoperative aspirin ingestion, etc.; 2) establish a quality management program, including a survey of transfusion practices that emphasizes physician education and availability of real-time laboratory testing to guide transfusion therapy; 3) adopt a multimodal approach using institution-proven techniques; and 4) continually reassess blood product use and analyze the cost-benefits of blood conservation interventions.

Transesophageal echocardiography as an important tool in the diagnosis of postinfarction papillary muscle rupture.

Papillary muscle complicating acute myocardial infarction is an uncommon but potentially catastrophic event. We present 3 such cases to illustrate the difficulties in early identification of rupture. In each case, transesophageal echocardiography was employed providing rapid and unequivocal identification of the disorder. Prompt surgical intervention led to survival in 2 patients.

Home heparin therapy used in a pregnant patient with a mechanical heart valve prosthesis.

The optimal anticoagulation therapy for pregnant patients with a mechanical valve prosthesis is uncertain, but teratogenic effects and the high incidence of fetal loss associated with dicumarol derivatives limit the use of these agents as anticoagulants in this setting. A patient with a mechanical valve prosthesis, in the first trimester of pregnancy, stopped taking her warfarin because of personal fears about teratogenicity. Prosthetic valve thrombosis developed, and she required redo mitral valve replacement. Another mechanical prosthesis was inserted without maternal or fetal injury. The patient was maintained on continuous home, intravenous, high-dose heparin therapy for the remainder of her pregnancy. This therapy resulted in a successful pregnancy and delivery without valve thrombosis, hemorrhagic events, or maternal or fetal compromise.