Biomechanical stability of hernia-damaged abdominal walls.

Hernia occurs when the peritoneum and/or internal organs penetrate through a defect in the abdominal wall. Implanting mesh fabrics is a common way to reinforce the repair of hernia-damaged tissues, despite the risks of infection and failure associated with them. However, there is neither consensus on the optimum mesh placement within the abdominal muscles complex nor on the minimum size of hernia defect that requires surgical correction. Here we show that the optimum position of the mesh depends on the hernia location; placing the mesh on the transversus abdominis muscles reduces the equivalent stresses in the damaged zone and represents the optimum reinforcement solution for incisional hernia. However, retrorectus reinforcement of the linea alba is more effective than preperitoneal, anterectus, and onlay implantations in the case of paraumbilical hernia. Using the principles of fracture mechanics, we found that the critical size of a hernia damage zone becomes severe at 4.1 cm in the rectus abdominis and at larger sizes (5.2-8.2 cm) in other anterior abdominal muscles. Furthermore, we found that the hernia defect size must reach 7.8 mm in the rectus abdominis before it influences the failure stress. In other anterior abdominal muscles, hernia starts to influence the failure stress at sizes ranging from 1.5 to 3.4 mm. Our results provide objective criteria to decide when a hernia damage zone becomes severe and requires repair. They demonstrate where mesh should be implanted for a mechanically stable reinforcement, depending on the type of hernia. We anticipate our contribution to be a starting point for sophisticated models of damage and fracture biomechanics. For example, the apparent fracture toughness is an important physical property that should be determined for patients living with different obesity levels. Furthermore, relevant mechanical properties of abdominal muscles at various ages and health conditions would be significant to generate patient specific results.

Minimally invasive retroperitoneal pancreatic necrosectomy.

INTRODUCTION: This article describes a case series outlining the experience and results of the retroperitoneal minimally invasive pancreatic necrosectomy (MIPN) procedure performed by, or done under the supervision of, a single surgeon. METHODS: All data of the patients who underwent MIPN from 2006 to 2008 were entered into a prospectively maintained, computerized database. RESULTS: A total of 93 MIPN procedures were performed on 32 patients. All patients had severe acute pancreatitis. The median number of MIPN procedures per patient was 3. Only 6 patients needed intensive care unit (ICU) admission after MIPN. There were 15 complications, which included bleeding requiring transfusion (n = 3), bowel fistulae (n = 7), thromboembolic events (n = 2) and acute myocardial infarction (n = 3). Four patients died after the procedure (13%); 1 died of ongoing multiorgan failure in spite of the MIPN. Four patients developed pancreatic pseudocysts within the follow-up period of 2 years. Three of these patients required intervention. CONCLUSION: This case series demonstrates that MIPN can be performed with acceptable morbidity and mortality and with good end results. The ICU dependency after the procedure is minimal. As seen in this series, multiple MIPNs may be needed to eradicate the necrosis satisfactorily. and IAP.

Laparoscopic resection for a gastric pheochromocytoma: a rare presentation of an uncommon tumor.

Pheochromocytoma is a rare tumor of the stomach, having only been reported 6 times in the published literature. We report the first case of gastric pheochromocytoma treated by laparoscopic partial gastrectomy.

Endoscopic total retroperitoneal distal pancreatectomy in a large animal model.

Traditionally, distal pancreatic lesions are resected by the open technique. An ever-increasing number of laparoscopic transperitoneal distal pancreatectomy cases are being reported. This study explores the possibility of performing distal pancreatectomy via an endoscopic retroperitoneal approach. This study was done in two stages using a total of 15 pigs: the first stage involved dissection in euthanized pigs, and the second stage involved anesthetized pigs. In both stages of the study, distal pancreatectomy could be performed within an acceptable time frame and with acceptable resection margins and morbidity rate. We introduce the concept of endoscopic total retroperitoneal distal pancreatectomy as an approach for distal pancreatectomy.

Deep venous thrombosis prophylaxis: are guidelines being followed?

INTRODUCTION: The purposes of the present study were to determine whether patients in The Canberra Hospital are receiving appropriate Deep Venous Thrombosis (DVT) prophylaxis, and to ascertain the awareness of appropriate treatment by clinicians. METHODS: Part 1 of the present study comprised of a point prevalence study of The Canberra Hospital inpatients. Patients were assessed for the risk of their developing DVT. The prophylaxis they were receiving was documented. In Part 2 of the present study, clinicians at The Canberra Hospital filled out a questionnaire that outlined three case scenarios. They were required to identify the risk group and appropriate prophylaxis for each group. Consultants, registrars and junior medical officers were assessed separately. RESULTS: The results of Part 1 of the present study showed that the majority of inpatients in The Canberra Hospital are not receiving appropriate prophylaxes according to international guidelines. Graduated compression stockings are rarely used, and often ineffectively applied. All groups performed poorly in Part 2 of the present study. Participants were frequently unable to identify the risk group for a particular scenario. There was also confusion regarding the appropriate prophylaxis for a particular risk group. DISCUSSION: Deep Venous Thrombosis is a major problem among hospitalized patients. However, despite its importance, there is a lack of appropriate prophylaxes being instituted. This, together with the poor performance of the participating clinicians in Part 2 of the present study,indicate that there are significant problems in The Canberra Hospital regarding DVT prophylaxes and that steps need to be taken to overcome these problems.