Objective: Recombinant factor VIIa can decrease postoperative bleeding after cardiac surgery. However, the potential for recombinant factor VIIa to cause early vascular graft occlusion at the site of new vascular anastomoses has not been fully explored. We hypothesized that recombinant factor VIIa would cause a dose-dependent reduction in vascular graft patency in rabbits.Methods: Reversed end-to-end interpositional vein grafts were sutured into the carotid artery of heparinized rabbits, and then recombinant factor VIIa (300 mu g/kg, 90 mu g/kg, or 20 mu g/kg intravenously) or placebo was administered (n = 16/group). Graft patency was assessed at 24 hours using a vascular ultrasound probe. Factor VII activity levels were measured using a prothrombin time-based assay. In different rabbits, the patency of venous end-to-side anastomoses and simple carotid arterial repairs was assessed (recombinant factor VIIa, 300 mu g/kg vs placebo, n = 8/group). Data were analyzed using Fisher's exact test, t tests, or analysis of variance.Results: Physiologic variables (activated clotting time, hemoglobin, pH, Pao(2)) and vessel diameter were not different between groups. Vein graft patency was reduced (93.8%, 81.2%, 13.8%, and 6.3%) as factor VII activity levels increased (1.8 +/- 0.4, 4.4 +/- 2.1, 11.8 +/- 4.7, and 23.6 +/- 16.9 U/mL, respectively) with increasing doses of recombinant factor VIIa administered (0, 20, 90, and 300 mu g/kg, respectively, P < .05). Patency in the arterial repairs and end-to-side venous grafts was also reduced in recombinant factor VIIa-treated rabbits (P < .05 for both).Conclusions: This study suggests that recombinant factor VIIa is associated with a dose-dependent increase in fresh vascular graft occlusion. Higher doses of recombinant factor VIIa may be associated with increased thrombotic outcomes. (J Thorac Cardiovasc Surg 2011; 142: 418-23)

BACKGROUND:Median sternotomy infection and bony nonunion are two commonly described complications which occur in 0.4-5.1% of cardiac procedures. Although relatively infrequent, these complications can lead to significant morbidity and mortality. The aim of this retrospective study is to evaluate the initial experience of a transverse plate fixation system following wound complications associated with sternal dehiscence with or without infection following cardiac surgery.METHODS:A retrospective chart review of 40 consecutive patients who required sternal wound reconstruction post sternotomy was performed. Soft tissue debridement with removal of all compromised tissue was performed. Sternal debridement was carried using ronguers to healthy bleeding bone. All patients underwent sternal fixation using three rib plates combined with a single manubrial plate (Titanium Sternal Fixation System®, Synthes). Incisions were closed in a layered fashion with the pectoral muscles being advanced to the midline. Data were expressed as mean±SD, Median (range) or number (%). Statistical analyses were made by using Excel 2003 for Windows (Microsoft, Redmond, WA, USA).RESULTS:There were 40 consecutive patients, 31 males and 9 females. Twenty two patients (55%) were diagnosed with sternal dehiscence alone and 18 patients (45%) with associated wound discharge. Thirty eight patients went on to heal their wounds. Two patients developed recurrent wound infection and required VAC therapy. Both were immunocompromised. Median post-op ICU stay was one day with the median hospital stay of 18 days after plating.CONCLUSION:Sternal plating appears to be an effective option for the treatment of sternal wound dehiscence associated with sternal instability. Long-term follow-up and further larger studies are needed to address the indications, benefits and complications of sternal plating.

Background Sternal instability with mediastinitis is a very serious complication after median sternotomy. Biomechanical studies have suggested superiority of rigid plate fixation over wire cerclage for sternal fixation. This study tests the hypothesis that sternal closure stability can be improved by adding plate fixation in a human cadaver model. Methods Midline sternotomy was performed in 18 human cadavers. Four sternal closure techniques were tested: (1) approximation with six interrupted steel wires; (2) approximation with six interrupted cables; (3) closure 1 (wires) or 2 (cables) reinforced with a transverse sternal plate at the sixth rib; (4) Closure using 4 sternal plates alone. Intrathoracic pressure was increased in all techniques while sternal separation was measured by three pairs of sonomicrometry crystals fixed at the upper, middle and lower parts of the sternum until 2.0 mm separation was detected. Differences in displacement pressures were analyzed using repeated measures ANOVA and Regression Coefficients. Results Intrathoracic pressure required to cause 2.0 mm separation increased significantly from 183.3 ± 123.9 to 301.4 ± 204.5 in wires/cables alone vs. wires/cables plus one plate respectively, and to 355.0 ± 210.4 in the 4 plates group (p < 0.05). Regression Coefficients (95% CI) were 120 (47–194) and 142 (66–219) respectively for the plate groups. Conclusion Transverse sternal plating with 1 or 4 plates significantly improves sternal stability closure in human cadaver model. Adding a single sternal plate to primary closure improves the strength of sternal closure with traditional wiring potentially reducing the risk of sternal dehiscence and could be considered in high risk patients.

BACKGROUND:Carpal tunnel syndrome is one of the most common and disabling work injuries in North America. Patients with carpal tunnel syndrome are often associated with substantial productivity loss and cost both at work and at home. Several studies have examined the relationship of social supports as a predictor of returning to work following carpal tunnel release surgery (CTRS). However, no studies published to date have examined the relationship between social support and the ability to perform activities of daily living after having CTRS.OBJECTIVE:To examine whether a correlation exists between the degree of social support and hand function in terms of the ability to perform activities of daily living in patients who have had CTRS.METHODS:Patients in the present cross-sectional study were evaluated with two standardized questionnaires at least two months postoperatively following CTRS. The questionnaires consisted of the Multidimensional Scale of Perceived Social Support, which evaluated social support, and QuickDASH, which evaluated hand function. A correlation analysis was then performed to identify any relationships between the two questionnaires.RESULTS:In a sample of 20 patients, correlation analyses revealed that perceived social support was significantly associated with hand function scores postoperatively (r=-0.73, P<0.01). In addition, a statistically significant relationship existed between social support and the preoperative self-rating pain scores (r=-0.51, P<0.05). These results indicate that there is a strong association between the degree of social support and the ability to perform hand activities of daily living following CTRS.

Postoperative hemorrhage following cardiac surgery increases morbidity, mortality, and costs. Several case reports have described the successful use of recombinant factor VIIa to decrease or stop bleeding in patients undergoing cardiac surgery. The mechanism of action of recombinant factor VIIa is thought to be increased sitespecific thrombin generation by tissue factor-mediated activation of coagulation or from activated platelets. However, there have also been many reports of thrombotic complications after recombinant factor VIIa administration. Randomized clinical trials and further laboratory studies should help better clarify the efficacy, safety, costeffectiveness, and optimal dosing of recombinant factor VIIa in the cardiac surgical setting.