Postoperative Bleeding After Change in Heparin Supplier: A Cardiothoracic Center Experience.

OBJECTIVE: Unfractionated heparin is a mixture of glycosaminoglycans with different pharmacologic and pharmacokinetic properties. The literature suggests that blood loss after cardiac surgery is related to both elevated postoperative heparin concentrations and the potency of different heparin brands. DESIGN: An audit of the observed increase in the incidence of cardiac surgery-related bleeding after change in heparin supplier. Patient characteristics were compared between groups before and after a change in heparin brands. SETTING: Tertiary cardiothoracic center. PARTICIPANTS: All patients undergoing cardiac surgery between August 1, 2011, and April 30, 2012. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Two hundred eighty patients underwent surgery before a change in heparin brands and 216 after a change. Their preoperative and intraoperative characteristics were similar. Postoperative chest tube drainages and blood transfusions were significantly greater after the change in heparin brands (postoperative chest drainage 476.8 ± 393.1 v 344.8 ± 323.2 mL/6 h and 1,062.2 ± 738.8 v 841.8 ± 567.4 mL/24 h, respectively; both p < 0.001) despite the administration of larger amounts of protamine, fresh frozen plasma/platelet transfusions, and cryoprecipitate. Heparin recirculation within 24 hours of bypass was noted in about 70% of the samples tested using either anti-factor X activity or the thromboelastography ratio between nonheparinase R and heparinase-modified R and was not associated with the heparin brand. The likelihood ratio chi-square test for nested models identified an added predictive value of the heparin brand when included as a predictor of bleeding (chest drainage >800 mL/6 h) in a model comprising recirculation, assessed using either an elevated anti-factor X activity or ratio between nonheparinase R and heparinase-modified R. CONCLUSION: It is likely that the observed increase in postoperative bleeding was related to the pharmacologic properties of the new heparin brand rather than a higher incidence of heparin recirculation.

Red blood cell transfusion practice in children: current status and areas for improvement? A study of the use of red blood cell transfusions in children and infants.

BACKGROUND: Patterns of red blood cell (RBC) transfusion are less well understood for children than adults. This study was undertaken to document current pediatric practice, to identify specific areas for improving patient care and safety. STUDY DESIGN AND METHODS: All UK hospitals were invited to participate. All children less than 18 years old admitted and receiving a RBC transfusion during a 3-month period in 2009 were eligible for inclusion. RESULTS: A total of 160 of 247 (65%) sites treating children or neonates responded; 119 provided data on 1302 pediatric patients transfused in nonneonatal wards. A total of 74% of patients received a single RBC transfusion during their admission. More than half (53%) of recipients had a hematologic or oncologic underlying diagnosis, and 33% were on general pediatric wards. The median pretransfusion hemoglobin (Hb) level was 7.9 g/dL (interquartile range [IQR], 6.9-9.4 g/dL), varying by location and diagnosis. The median volume prescribed was 15 mL/kg (IQR, 11.8-19.2 mL/kg). Prescribing by units instead of milliliters was recorded for 493 of 1264 (39%) of transfusions. For 734 of 1302 (56%) where Hb levels were available within 2 days between pre- and posttransfusion Hb, the median transfusion increment was 2.8 g/dL (IQR, 1.4-3.9 g/dL). CONCLUSION: This study of UK pediatric RBC transfusion practice has demonstrated significant variation in pretransfusion Hb, frequent prescribing in units rather than milliliters, and a high proportion of single transfusions during admissions. Future education and research should target transfusion triggers and prescription volumes for children in all clinical areas.

Can ROTEM thromboelastometry predict postoperative bleeding after cardiac surgery?

OBJECTIVE: To evaluate the predictive ability of ROTEM thromboelastometry (Pentapharm, Basel, Switzerland) to identify patients bleeding more than 200 mL/h in the early postoperative period after cardiac surgery. DESIGN: A prospective observational study. SETTING: A single university hospital. PARTICIPANTS: Fifty-eight adult male and female patients undergoing primary coronary artery revascularization. INTERVENTIONS: Blood samples taken preoperatively and at 1, 2, and 3 hours after surgery. MEASUREMENTS AND MAIN RESULTS: Eight patients bled at least 200 mL/h in the study period. All (100%) had at least 1 abnormal ROTEM result in the study period. Of the 49 patients not found to be bleeding more than 200 mL/h in any of the first 4 postoperative hours, 46 (94%) had at least 1 abnormal ROTEM result. The positive and negative predictive values were 14.8% and 100%, respectively. CONCLUSIONS: ROTEM thromboelastometry has poor predictive utility to identify patients who bleed more than 200 mL/h in the early postoperative period after cardiac surgery. However, its negative predictive value was good.

Correlation between thrombin potential and bleeding after cardiac surgery in adults.

We used a sensitive assay to measure thrombin potential in 20 patients who underwent cardiopulmonary bypass surgery for coronary artery bypass grafts. We measured coagulation factors II, V, VII, VIII and X. Blood loss was measured as the total amount in the mediastinal drains in the first 24 h postoperatively. Thrombin potential was median 107 nmol/l.min (range 62-181) preoperatively and median 46 nmol/l.min (range 19-120) postoperatively. Coagulation factors II, V, VII,VIII and X were within normal limits preoperatively. Factor II fell from 77 IU/dl preoperatively to 37 IU/dl at 120 min postoperatively. Factor V fell from 85 IU/dl preoperatively to 61 IU/dl postoperatively. Factor VII fell from 91 IU/dl to 66 IU/dl postoperatively. Factor VIII was 128 IU/dl preoperatively and 127 IU/dl postoperatively. Factor X fell from 90 IU/dl preoperatively to 50 IU/dl postoperatively. Total blood loss in 24 h in the mediastinal drains postoperatively was mean 673 ml, median 650 ml (range 250-2000). Reduction in thrombin potential correlated inversely with postoperative blood loss, r= -0.75 (Spearman correlation). The fall in the thrombin potential correlated with the prothrombin level (r = 0.75) and factor X (r = 0.47).

The left axillary artery--a new approach for transcatheter aortic valve implantation.

OBJECTIVE: Transcatheter aortic valve implantation (TAVI) is an alternative treatment for aortic stenosis in selected cases, but requires appropriate vascular access. We report our initial clinical experience with a novel endovascular approach for TAVI. METHODS: Between 1 April 2007 and 31 August 2008, 48 patients underwent TAVI at our institution. Of these, eight patients (17%) were deemed to be best served through direct surgical exposure of the left axillary artery rather than a trans-femoral or TA approach. RESULTS: Procedural success was achieved in seven of eight cases. In one patient the axillary artery was too small to accept the 18 French sheath. In the remaining seven, the device was implanted without major complication and with only trivial paravalvular aortic regurgitation. The in-hospital mortality was 0%. The 30-day mortality was 12.5% (one patient). There was one localised dissection at the origin of the vertebral artery. There was one late pericardial effusion and a permanent pacemaker was implanted in five patients. CONCLUSIONS: TAVI can be performed through a left axillary artery approach. This is a technically simple procedure and, in this small initial clinical experience, was performed with encouraging results. It is a realistic option in patients in whom neither the trans-femoral or trans-apical approaches are optimal.

Coronary artery surgery: cardiotomy suction or cell salvage?

Coronary artery bypass grafting (CABG) today results in what may be regarded as acceptable levels of blood loss with many institutions avoiding allogeneic red cell transfusion in over 60% of their patients. The majority of cardiac surgeons employ cardiotomy suction to preserve autologous blood during on-pump coronary artery bypass surgery; however the use of cardiotomy suction is associated with a more pronounced systemic inflammatory response and a resulting coagulopathy as well as exacerbating the microembolic load. This leads to a tendency to increased blood loss, transfusion requirement and organ dysfunction. Conversely, the avoidance of cardiotomy suction in coronary artery bypass surgery is not associated with an increased transfusion requirement. There is therefore no indication for the routine use of cardiotomy suction in on-pump coronary artery surgery.

Successful treatment of endogenous lipoid pneumonia due to Niemann-Pick Type B disease with whole-lung lavage.

In Type B Niemann-Pick disease, progressive pulmonary infiltration is a major cause of morbidity and mortality, although the disease is usually diagnosed before adulthood in other organ systems. To date, no successful treatment of pulmonary involvement by Niemann-Pick disease has been documented. We describe the case of a patient with Niemann-Pick Type B disease who presented with extensive endogenous lipoid pneumonia and life-threatening hypoxia following bypass grafting for severe coronary artery disease. A surgical lung biopsy at the time of grafting revealed characteristic histology and ultrastructural features of Niemann-Pick disease, with confirmatory findings in biochemical studies. Because of the severity of the patient's symptoms, bilateral whole-lung lavage was undertaken, leading to symptomatic improvement, lessening of parenchymal opacification on high-resolution computed tomographic scanning, and a marked improvement in resting arterial oxygen tension while breathing air to 10.3 kPa from 8.4 kPa. Whole-lung lavage may be a potentially useful modality of treatment for patients with pulmonary involvement by Niemann-Pick Type B disease.