Comparing the da Vinci Si Single Console and Dual Console in Teaching Novice Surgeons Suturing Techniques

Background and Objectives:

Robot-assisted laparoscopic surgery is often taught with the surgical mentor at the surgeon console and the trainee at the patient''s bedside. The da Vinci dual console (Intuitive Surgical, Sunnyvale, California) allows a surgical mentor to teach with both the mentor and the trainee working at a surgeon console simultaneously. The purpose of this study is to evaluate the effectiveness of the dual console versus the single console for teaching medical students robotic tasks.

Methods:

Forty novice medical students were randomized to either the da Vinci single-console or dual-console group and were taught 4 knot-tying techniques by a surgical mentor. The students were timed while performing the tasks.

Results:

No statistically significant differences in mean task times were observed between the single- and dual-console groups: interrupted stitch with a 2-handed knot (300 seconds for single vs 294 seconds for dual, P = .59), interrupted stitch with a 1-handed knot (198 seconds for single vs 212 seconds for dual, P = .88), figure-of-8 stitch with a 2-handed knot (261 seconds for single vs 219 seconds for dual, P = .20), and figure-of-8 stitch with a 1-handed knot (200 seconds for single vs 199 seconds for dual, P = .53).

Conclusion:

No significant difference was observed in performance time when teaching knot-tying techniques to medical students using the da Vinci dual console compared with the single console. More research needs to be performed on the utility of the da Vinci dual console in surgical training.     

Technical considerations for platelet aggregation and related problems

Platelet aggregation generally is ordered by the physician to evaluate platelet function in hemorrhagic or thrombotic disorders. Malfunction of the platelet may be the result of an intrinsic congenital defect or an acquired problem induced by drugs or certain circulating plasma factors. It is necessary to obtain information from the patient with respect to family history, drug ingestion, physical or mental stress. In addition, other laboratory studies should be obtained to rule out general coagulation disorders affecting the plasma factors. A bleeding time will be helpful in establishing the severity of any platelet dysfunction. Technical considerations with regard to the preparation of the samples are of primary importance in determining platelet aggregation. Aggregating studies require the use of a variety of binding agents. (Studies on shape change, adhesion of platelets, release of platelet granule substance, and or lysis with extrusion of cytoplasmic constituents may be helpful in certain cases.) Instrumentation for platelet aggregation presently is available in many hospitals. The technical factors to be considered for routine aggregation studies include the type and strength of anticoagulant, centrifugation technique used in preparing the platelet-rich and platelet-poor plasma, platelet concentration, time of storage of the sample after venipuncture and after centrifugation, temperature, and the mixing of the sample. In general, critical concentrations of each reagent should be employed to improve the discrimination capability of the assay. Small differences in response may be obliterated by using excessive concentrations of a given reagent. Comparison in response to the test platelets with control platelets is best done at the same time by performing the aggregation in a dual instrument so that handling procedures will be identical and artifactual differences eliminated.     

Review of the comparative effectiveness of radical prostatectomy,radiation therapy,or expectant management of localized prostate cancer in registry data

Summary

Evidence regarding the effectiveness of treatment for prostate cancer is primarily based on randomized controlled trials. Long-term outcomes are generally difficult to evaluate within experimental studies and may benefit from large pools of observational data. We conducted a systematic review of administrative and registry studies to evaluate the comparative effectiveness of treatment for clinically localized prostate cancer on overall and prostate-cancer specific mortality.

Deficient arginase II expression without alteration in arginase I expression attenuated experimental autoimmune encephalomyelitis in mice

In the past there have been a multitude of studies that ardently support the role of arginase II (Arg II) in vascular and endothelial disorders; however, the regulation and function of Arg II in autoimmune diseases has thus far remained unclear. Here we report that a global Arg II null mutation in mice suppressed experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis. During EAE, both Arg I and Arg II were induced in spinal cords, but only Arg II was induced in spleens and splenic dendritic cells (DCs). DC activation by lipopolysaccharide (LPS), CD40L or TLR8 agonist significantly enhanced Arg II expression without affecting Arg I expression. Conversely, DC differentiating cytokines [IL‐4 and granulocyte macrophage‐colony‐stimulating factor (GM‐CSF)] yielded opposite effects. In addition, Arg I and Arg II were regulated differentially during Th1 and Th17 cell polarization. Arg II deficiency in mice delayed EAE onset, ameliorated clinical symptoms and reduced myelin loss, accompanied by a remarkable reduction in the EAE‐induced spinal cord expression of Th17 cell markers (IL‐17 and RORγt). The abundance of Th17 cells and IL‐23⁺ cells in relevant draining lymph nodes was significantly reduced in Arg II knockout mice. In activated DCs, Arg II deficiency significantly suppressed the expression of Th17‐differentiating cytokines IL‐23 and IL‐6. Interestingly, Arg II deficiency did not lead to any compensatory increase in Arg I expression in vivo and in vitro. In conclusion, Arg II was identified as a factor promoting EAE likely via an Arg I‐independent mechanism. Arg II may promote EAE by enhancing DC production of Th17‐differentiating cytokines. Specific inhibition of Arg II could be a potential therapy for multiple sclerosis.     

Patients at elevated risk of major adverse events following endarterectomy for asymptomatic carotid stenosis

Background

Carotid endarterectomy (CEA) as treatment in patients with asymptomatic carotid stenosis is the subject of much debate.

Methods

The National Surgical Quality Improvement Program database from 2005 to 2012 was queried. Patients undergoing CEA for asymptomatic carotid stenosis were identified. Preoperative risk factors and patient demographics were compared using chi-square analysis and logistic regression to determine their relation with stroke and death.

Results

During an 8-year period, 24,211 CEAs performed for asymptomatic carotid stenosis were identified. Patients with dependent functional status (12.5%), recent myocardial infarction (6.3%), chronic heart failure (5.0%), hypoalbuminemia (4.8%), angina (4.1%), dialysis dependence (3.4%), steroid dependence (3.4%), chronic obstructive pulmonary disease (3.3%), and American Society of Anesthesiologists > 3 (3.2%) had a clinically significant increase in risk of stroke and death. Patients with none of the above risk factors had a stroke and death rate of 1.08%, which was significantly less than the overall stroke and death rate (P < .001).

Conclusions

A high-risk subset of patients undergoing CEA for asymptomatic carotid stenosis can be identified. If patient selection is optimized and perioperative morbidity and mortality are minimized, CEA will continue to play an important role in stroke prevention for those with significant asymptomatic carotid stenosis.     

Molecular Basis of Intervertebral Disc Degeneration and Herniations: What Are the Important Translational Questions?

Background

Intervertebral disc degeneration is a common condition with few inexpensive and effective modes of treatment, but current investigations seek to clarify the underlying process and offer new treatment options. It will be important for physicians to understand the molecular basis for the pathology and how it translates to developing clinical treatments for disc degeneration. In this review, we sought to summarize for clinicians what is known about the molecular processes that causes disc degeneration.

Results

A healthy disc requires maintenance of a homeostatic environment, and when disrupted, a catabolic cascade of events occurs on a molecular level resulting in upregulation of proinflammatory cytokines, increased degradative enzymes, and a loss of matrix proteins. This promotes degenerative changes and occasional neurovascular ingrowth potentially contributing to the development of pain. Research demonstrates the molecular changes underlying the harmful effects of aging, smoking, and obesity seen clinically while demonstrating the variable influence of exercise. Finally, oral medications, supplements, biologic treatments, gene therapy, and stem cells hold great promise but require cautious application until their safety profiles are better outlined.

Conclusions

Intervertebral disc degeneration occurs where there is a loss of homeostatic balance with a predominantly catabolic metabolic profile. A basic understanding of the molecular changes occurring in the degenerating disc is important for practicing clinicians because it may help them to inform patients to alter lifestyle choices, identify beneficial or harmful supplements, or offer new biologic, genetic, or stem cell therapies.