Effects of heparin bridging anticoagulation on perioperative bleeding and thromboembolic risks in patients undergoing abdominal malignancy surgery.

Recent publications provided controversial results indicating that perioperative heparin bridging anticoagulation (HBA) increased the bleeding risk without decreasing the thromboembolic risk in patients undergoing minor surgery. To investigate if this is also the case in high-risk patients undergoing major abdominal malignancy surgery, we retrospectively collected data of 3268 patients over a 10-year period. After the interruption of preoperative antithrombotic agents, HBA was initiated with a prophylactic-dose of unfractionated heparin in 133 patients (HBA group), and 62 patients did not receive HBA (non-HBA group). The incidence of exogenous blood transfusion (EBT) and thromboembolic events (TEEs) within 30 days after surgery were compared between the HBA and non-HBA groups. The results showed that the incidence of EBT and TEEs was similar between the two groups (23.3 vs 19.4 %; P = 0.535) and (4.1 vs 3.2 %; P = 0.821), respectively. The amount of intraoperative bleeding and the length of postoperative hospital stay were also similar [median (quantile 1-3); 192 (71-498) vs 228 ml (100-685); P = 0.422] and [12 (9-19) vs 14.5 days (10-21); P = 0.052], respectively. These findings may suggest it is unlikely that prophylactic-dose HBA affects bleeding and thromboembolic risks in patients undergoing major abdominal malignancy surgery.

[Thrombotic and Bleeding Risks of Patients on Antiplatelet Therapy Undergoing Major Abdominal Malignancy Surgery].

BACKGROUND: Controversies still exist whether to continue or withdraw aspirin (ASA) perioperatively. This study was performed to determine whether patients on preoperative antiplatelet therapy (APT) benefit from continuing ASA in terms of thrombotic and bleeding risk prevention. METHODS: Among 307 consecutive patients who were on APT preoperatively for the secondary prevention of cardiovascular disease and who underwent elective major abdominal malignancy surgery, 148 patients had all the preoperative APT withdrawn and the remaining 159 patients continued only ASA. Comparisons were made between the 2 groups regarding the rate and the amount of exogenous blood transfusion as well as the incidence of thromboembolic events (TEEs) within 1 month after surgery. RESULTS: The incidence of perioperative TEEs of the APT withdrawn group was significantly higher than that of the ASA group (6.2% vs 0%, P = 0.005), while the rate and the amount of exogenous blood transfusion were not different each other (23.6% vs 17.0%, P = 0.146 and 4 units vs 4 units, P = 0.544, respectively). CONCLUSIONS: Considering the relatively low bleeding risk when continued and the increased thrombotic risk after withdrawal, ASA should be continued perioperatively in patients undergoing major abdominal malignancy surgery.

Presence and characterization of prostaglandin D2-related molecules in nasal mucosa of patients with allergic rhinitis.

BACKGROUND: Prostaglandin D2 (PGD2) is the major prostanoid produced in the acute phase of allergic reactions. However, its pathophysiological role in addition to the pathway of production in allergic rhinitis remains unclear. We sought to determine the expression of synthases and receptors for PGD2 in human nasal mucosa. These expressions were compared between allergic and nonallergic patients. METHODS: The expression and localization of hematopoietic-type (h)-PGD2 synthase (PGDS) and lipocalin-type (l)-PGDS were detected by immunohistochemistry. The expression of D prostanoid (DP) receptor and chemoattractant receptor-homologous molecule expressed on Th2 cells (CRTH2) was determined by quantitative real-time PCR. RESULTS: The h-PGDS but not l-PGDS was clearly expressed in nasal mucosa. The expression of h-PGDS in allergic patients was significantly higher than in control patients without mucosal hypertrophy. A variety of infiltrating cells including mast cells, eosinophils, macrophages, and lymphocytes as well as constitutive cells such as epithelial cells and fibroblasts expressed h-PGDS. The expression of both DP and CRTH2 was confirmed also. Although either the amount of DP or the amount of CRTH2 was not correlated with serum levels of IgE, the amount of CRTH2 but not DP was highly and significantly correlated with the number of eosinophils infiltrating into nasal musosa. CONCLUSION: These results suggest that PGD2 is released via the action of h-PGDS from various cells, and the expression of h-PGDS may be associated with the hypertrophic inflammation in the nose. In addition, ligation of PGD2 to CRTH2 appears to be selectively involved in eosinophil recruitment into the nose regardless of atopic status.