Assessment of endothelium and inflammatory response at the onset of reperfusion injury in hand surgery

Background Activation of the endothelium, complement activation and generation of cytokines are known events during ischemia-reperfusion (I/R) that mediate tissue injury. Our aim was to elucidate their respective participation at the onset of the reperfusion phase. Tourniquet application in hand surgery causes short-term ischemia, followed by reperfusion and was therefore used as the model in this study. Methods Ten patients were included in the study after obtaining informed consent. A tourniquet was placed on the upper arm and inflated to 250 mmHg for 116 ± 16 min, during which the surgery was performed. Venous blood and tissue samples from the surgical area were taken at baseline as well as 0, 2, and 10 min after reperfusion and analyzed for the following parameters: Endothelial integrity and/or activation were analyzed by measuring heparan sulfate and syndecan-1 in serum, and vWF, heparan sulfate proteoglycan as well as CD31on tissue. Complement activation was determined by C3a and C4d levels in plasma, levels of C1-inhibitor in serum, and IgG, IgM, C3b/c, and C4b/c deposition on tissue. Cytokines and growth factors IL-5, IL-6, IL-7, IL-8, IL-10, IL-17, G-CSF, GM-CSF, MCP-1, TNFα, VEGF, and PDGF bb were measured in the serum. Finally, CK-MM levels were determined in plasma as a measure for muscle necrosis. Results Markers for endothelial activation and/or integrity as well as complement activation showed no significant changes until 10 min reperfusion. Among the measured cytokines, IL-6, IL-7, IL-17, TNFα, GM-CSF, VEGF, and PDGF bb were significantly increased at 10 min reperfusion with respect to baseline. CK-MM showed a rise from baseline at the onset of reperfusion (p < 0.001) and dropped again at 2 min (p < 0.01) reperfusion, suggesting ischemic muscle damage. Conclusions In this clinical model of I/R injury no damage to the endothelium, antibody deposition or complement activation were observed during early reperfusion. However, an increase of pro-inflammatory cytokines and growth factors was shown, suggesting a contribution of these molecules in the early stages of I/R injury.

Rationales for the Bernese approaches in acetabular surgery

PURPOSE: To present two new approaches to acetabular surgery that were established in Berne, and which aim at enhanced visualization and anatomical reconstruction of acetabular fractures. METHOD: The trochanteric flip osteotomy allows for surgical hip dislocation, and was introduced as a posterior approach for acetabular fracture management involving the posterior column and wall. For acetabular fractures predominantly involving the anterior column and the quadrilateral plate, the Pararectus approach is described. RESULTS: Full exposure of the hip joint, as provided by the trochanteric flip osteotomy, facilitates anatomical reduction of acetabular or femoral head fractures and safe positioning of the anterior column screw in transverse or T-shaped fractures. Additionally, the approach enables osteochondral transplantation as a salvage procedure for severe chondral femoral head damage and osteoplasty of an associated inadequate offset at the femoral head-neck junction. The Pararectus approach allows anatomical restoration with minimal access morbidity, and combines advantages of the ilioinguinal and modified Stoppa approaches. CONCLUSIONS: Utilization of the trochanteric flip osteotomy eases visualization of the superior aspect of the acetabulum, and enables the evaluation and treatment of chondral lesions of the femoral head or acetabulum and labral tears. Displaced fractures of the anterior column with a medialized quadrilateral plate can be addressed successfully through the Pararectus approach, in which surgical access is associated with minimal morbidity. However, long-term results following the two presented Bernese approaches are needed to confirm that in the treatment of complex acetabular fractures the rate of poor results in almost one-third of all cases (as currently yielded using traditional approaches) might be reduced by the utilization of the presented novel approaches.

[Improve your skills!: evaluation of a 2.5-day basic course in vascular surgery for surgical trainees]

The traditional surgical training in the operating room (OR) is often complemented by participation in workshops and on simulators. The foundation Vascular International offers basic courses for vascular surgery techniques with training on pulsatile circulation, lifelike anatomical models. The aim of this study was to assess the efficacy of a 2.5-day intensive course on basic skills in vascular surgery.

Morbidity rate of reoperation in thyroid surgery: a different point of view

Goitre recurrence is a common problem following subtotal thyroid gland resection for multinodular goitre disease. The aim of the present study was to evaluate morbidity rate in relation to the side of initial and redo-surgery for recurrent disease.

Impact of surgical technique on operative morbidity and its socioeconomic benefit in thyroid surgery

The aim of this retrospective cohort study was to evaluate the rate of complications in relation to the extent of surgery and some of its consequences.

Haemostatic agents used in periradicular surgery: an experimental study of their efficacy and tissue reactions

AIM: To evaluate the haemostatic efficacy and the histologic tissue responses after the application of different haemostatic agents used in periradicular surgery. METHODOLOGY: The study was conducted in the calvarium of six rabbits. Standardized bone defects (diameter 4 mm) were trephined, and different haemostatic agents were applied and compared with control defects: bone wax (left for 10 min), Stasis (ferric sulphate, left for 5 s), Expasyl (aluminium chloride, left for 2 min and left permanently in situ), and a combination of Expasyl (2 min) and Stasis (5 s). The sites were photographed before the application and after the removal of the haemostatic agents. Three independent examiners judged the initial and final bleeding (on the photographs) using a bleeding score for each site and treatment. The results were compared using Wilcoxon's signed rank test. For the histologic analysis, three animals were killed after 3 weeks and three animals after 12 weeks. Transverse, nondecalcified sections were stained with combined basic fuchsin and toluidine blue for descriptive histology. RESULTS: The most efficient haemorrhage control was provided by Expasyl in combination with Stasis and by Expasyl alone, whereas bone wax had the weakest bleeding reduction effect. The histologic analysis after 3 weeks demonstrated an inflammatory and foreign body tissue response towards all haemostatic agents. At 12 weeks, this tissue response was less pronounced but still present in sites treated with bone wax or Expasyl. In general, the inflammatory tissue reactions were limited to the bone defects, and never extended into the surrounding tissues. CONCLUSIONS: Expasyl alone or in combination with Stasis appeared to be the most efficient of tested agents to control the bleeding within the bony defects created in a rabbit calvarium model.

Arterio-venous gradients of free energy change for assessment of systemic and splanchnic perfusion in cardiac surgery patients

OBJECTIVE: Adequacy of organ perfusion depends on sufficient oxygen supply in relation to the metabolic needs. The aim of this study was to evaluate the relationship between gradients of free energy change, and the more commonly used parameter for the evaluation of the adequacy of organ perfusion, such as oxygen-extraction in patients undergoing valve replacement surgery using normothermic cardiopulmonary bypass (CPB). METHODS: In 43 cardiac patients, arterial, mixed venous, and hepato-venous blood samples were taken synchronously after induction of anaesthesia (preCPB), during CPB, and 2 and 7 h after admission to the intensive care unit (ICU+2, ICU+7). Blood gas analysis, cardiac output, and hepato-splanchnic blood flow were measured. Free energy change gradients between mixed venous and arterial (-deltadeltaG(v - a)) and hepato-venous and arterial (-deltadeltaG(hv - a)) compartments were calculated. MEASUREMENTS AND RESULTS: Cardiac index (CI) increased from 1.9 (0.7) to 2.8 (1.3) L/min/m (median, inter-quartile range) (p = 0.001), and hepato-splanchnic blood flow index (HBFI) from 0.6 (0.22) to 0.8 (0.53) L/min/m (p = 0.001). Despite increasing flow, systemic oxygen extraction increased after CPB from 24 (10)% to 35 (10)% at ICU+2 (p = 0.002), and splanchnic oxygen extraction increased during CPB from 37 (19)% to 52 (14)% (p = 0.001), and remained high thereafter. After CPB, high splanchnic and systemic gradients of free energy change gradients were associated with high splanchnic and systemic oxygen extraction, respectively (p = 0.001, 0.033, respectively). CONCLUSION: Gradients of free energy change may be helpful in characterising adequacy of perfusion in cardiac surgery patients independently from measurements or calculations of data from oxygen transport.