Construct and face validity of a virtual reality-based camera navigation curriculum.

INTRODUCTION: Camera handling and navigation are essential skills in laparoscopic surgery. Surgeons rely on camera operators, usually the least experienced members of the team, for visualization of the operative field. Essential skills for camera operators include maintaining orientation, an effective horizon, appropriate zoom control, and a clean lens. Virtual reality (VR) simulation may be a useful adjunct to developing camera skills in a novice population. No standardized VR-based camera navigation curriculum is currently available. We developed and implemented a novel curriculum on the LapSim VR simulator platform for our residents and students. We hypothesize that our curriculum will demonstrate construct and face validity in our trainee population, distinguishing levels of laparoscopic experience as part of a realistic training curriculum. METHODS: Overall, 41 participants with various levels of laparoscopic training completed the curriculum. Participants included medical students, surgical residents (Postgraduate Years 1-5), fellows, and attendings. We stratified subjects into three groups (novice, intermediate, and advanced) based on previous laparoscopic experience. We assessed face validity with a questionnaire. The proficiency-based curriculum consists of three modules: camera navigation, coordination, and target visualization using 0° and 30° laparoscopes. Metrics include time, target misses, drift, path length, and tissue contact. We analyzed data using analysis of variance and Student's t-test. RESULTS: We noted significant differences in repetitions required to complete the curriculum: 41.8 for novices, 21.2 for intermediates, and 11.7 for the advanced group (P < 0.05). In the individual modules, coordination required 13.3 attempts for novices, 4.2 for intermediates, and 1.7 for the advanced group (P < 0.05). Target visualization required 19.3 attempts for novices, 13.2 for intermediates, and 8.2 for the advanced group (P < 0.05). Participants believe that training improves camera handling skills (95%), is relevant to surgery (95%), and is a valid training tool (93%). Graphics (98%) and realism (93%) were highly regarded. CONCLUSIONS: The VR-based camera navigation curriculum demonstrates construct and face validity for our training population. Camera navigation simulation may be a valuable tool that can be integrated into training protocols for residents and medical students during their surgery rotations.

Hyaluronate-iodine complex: a new adjunct for the management of complex sternal wounds after a cardiac operation.

A wound-healing agent developed in the European Union is based on the combination of organic hyaluronan with inorganic iodine. The aim of this pilot study was to assess the efficacy and safety of hyaluronate-iodine in the treatment of sternal wounds. Eight patients with sternal wound dehiscence were entered into the study. After debridement, wounds were dressed with gauze soaked in hyaluronate-iodine. In one patient with an epipleural abscess, hyaluronate-iodine was instilled directly into the abscess cavity daily. Complete healing was achieved in 7 patients, and 1 patient underwent a reconstructive operation for wound closure. The mean (SD) length of treatment was 136 (114.2) days. No adverse effects or complications were apparent in this group. Hyaluronate-iodine is safe and effective in healing sternal wound dehiscence. Randomized controlled trials are needed for further validation.

Total parenteral nutrition and cancer: from the beginning.

The early development of total parenteral nutrition and its evolution as an adjunct to the nutritional, metabolic, and antineoplastic therapy of cancer patients is described. Examples related to the sine wave of responses to new data and discovery are placed in context to understand better past, present, and how and where to proceed in the future to achieve optimal results from multimodal comprehensive management of patients with malignancies. Practical and philosophic thoughts are proffered to justify continued, intensified, logical, controlled clinical studies directed toward establishing the most rational, safe, and effective use of total parenteral nutrition in treating patients with cancer.

Nutritional considerations in adult cardiothoracic surgical patients.

The importance of the preoperative nutritional status of cardiothoracic surgical patients in determining outcomes is demonstrated and discussed. Demographic, anthropometric, and biochemical changes in patients undergoing cardiothoracic surgery increase the importance of identifying those at risk for postoperative complications resulting from malnutrition. The interrelationships of chronic heart failure, cardiac cachexia, nutritional status, and nutritional support are identified and emphasized. The complexities of myocardial energetics and metabolism are outlined together with the nutrient needs for patients undergoing cardiac, pulmonary, or other intrathoracic operative procedures.

Nutrition management of geriatric surgical patients.

Surgery in geriatric patients is accompanied by increases in morbidity and mortality, increases in functional abnormalities and poor outcomes, and increases in severe malnutrition, compared with surgery of similar magnitude in nongeriatric patients. Hospitalized elderly patients are at significant risk of presenting with, or developing, protein-energy and other nutrient deficiencies. However, nutritional assessment of older geriatric patients, 65 to 100 years of age, is a challenging task because of lack of adequate age-specific reference data in this diverse and heterogeneous population. Dietary counseling and conscientious, aggressive nutritional support are required for optimal metabolic and surgical care of this age group.

Nutritional supplements in the surgical patient.

This article presents an overview of the current knowledge, status, and use of supplements by patients before surgical operations, together with the benefits expected of the supplements by the patients. The indications, potential advantages and disadvantages, and the relationships with various aspects of the preoperative preparation and postoperative management of surgical patients are discussed, with emphasis on the significant percentage of this population that is deficient in fundamental nutrients. Recent revisions and recommendations for some of the macronutrients are presented, together with a summary of federal regulations and an oversight of supplements.

Historical highlights of the development of enteral nutrition.

The most significant events and discoveries regarding the development of enteral nutrition (EN) dating back to 1500 BC are chronicled. A more detailed description and discussion of subsequent more recent progress during the past two decades is focused primarily on 3 of the most dynamic areas of endeavor: tight glycemic control; timing and combining of EN and total parenteral nutrition to meet early target nutrition goals in intensive care unit patients; and the role, advances, and future of immunonutrition. An abridged classification of solutions for enteral feeding, and a brief outline of key prudent oral dietary guidelines are also presented.

Cachexia, malnutrition, the refeeding syndrome, and lessons from Goldilocks.

Cachexia has plagued clinicians for centuries. Although all cachexia is related to malnutrition, cachexia associated with malignant diseases differs from starvation cachexia in that it is more recalcitrant to nutritional therapy. All cachexia responds to judicious nutritional support; however, cancer cachexia worsens autonomously as the disease advances and cannot be arrested or reversed by any known form of nutrition, hormonal, or pharmacologic therapy. Cachexia must be treated cautiously to avoid overfeeding syndrome, which may result in serious or dangerous complications or death.

Parenteral nutrition and nutritional support of surgical patients: reflections, controversies, and challenges.

An abridged background of the history, cause, and nature of early controversies related to the development and clinical application of total parenteral nutrition (TPN) is presented, followed by discussions of highlights of some of the more prominent controversies that continue to prevail, including nutritional support of geriatric patients with and without cancer, the importance of maintenance of normal glycemia, the primacy of nutrition support teams, and TPN versus total enteral nutrition. Reflections related to nutritional support and TPN are interspersed throughout the discussions, together with a compilation of legacies of TPN to the modern practice of medicine.

Historical highlights of the development of total parenteral nutrition.

The events and discoveries thought to be the most significant prerequisites to the development of total parenteral nutrition (TPN) dating back to the early 17th century are chronicled. A more detailed description and discussion of the subsequent early modern highlights of the basic and clinical research beginning in the mid-20th century and the advances culminating in the first demonstration of the feasibility and practicality of TPN, and its successful, safe and efficacious applications clinically, are presented. Some of the reasoning, insights, and philosophy of a pioneer clinician-scientist in the field are shared with readers.

Surgical skills assessment of applicants to general surgery residency.

BACKGROUND: Manual skill proficiency is not currently employed in selecting residents for general surgery training programs. The study objective was to assess whether the technical skill levels of applicants to a general surgery residency program are higher than those of internal medicine residents. MATERIAL AND METHODS: Forty-two applicants to a community general surgery program underwent manual skill testing on interview day. Four laparoscopic tasks on a virtual reality (VR) simulator (LapSim, Goteborg, Sweden) were tested. Performance scores were computer-generated. Participants' previous experience with other manual dexterity activities was assessed via a questionnaire. Applicants' self-perception of their surgical skills was correlated with their skill dexterity scores on the simulator. Candidates' simulator scores were also compared with those of a group of internal medicine interns (n = 9) and a group of mid-level surgical residents, PGY 2-3 (n = 7). RESULTS: Simulator scores of the applicants were significantly lower than those of mid-level surgical residents in all VR tasks (P < 0.05). The internal medicine interns scored higher that the surgery candidates in three of four simulator tasks. Participation in other manual dexterity activities was not associated with increased dexterity scores. CONCLUSION: This study suggests that surgical dexterity levels do not correlate with the self-assessed skill levels or with previous experience with other manual dexterity activities. Moreover, there appears to be no self-selection of applicants for surgery residency based on actual surgical skills. Selection criteria for surgical training, which incorporate technical proficiency skills, may potentially better discriminate those applicants with an aptitude for a surgical specialty.

[Evolution of surgical education through the 20th Century into the 21st Century.]

An abridged overview of the development of surgery and early surgical education, training and practice is presented, beginning in colonial America in the 18th century, extending throughout the 19th century, evolving rapidly during the 20th century, and progressing into the first decade of the 21st century. The metamorphosis and transformation of surgery training programs in the United States are described and discussed, together with some of the most relevant rationale and justifications for the many changes introduced, established, mandated and in progress. The current accreditation requirements, oversight, and governance of general surgery training programs; the incorporation of multiple technical and technological advances into general surgical practice; the addition of required training modules and systems to the programs; and their secondary implications, consequences, and impact upon the programs, are presented. These include financial and other resource impediments, the 80-h work week implications and constraints, the technological explosion, the demands of the required expanded general surgical curriculum and operative case experience, the continued erosion of general surgery by surgical and medical specialists, the increasing workload coupled with decreasing reimbursement for surgeons and their services; and the challenges and difficulties of amalgamating all of these confounding or conflicting factors into an effective and viable general surgery program. Finally, some of the personal insights, opinions, experiences, and philosophy of the author are incorporated into the narrative.

Initial experience using a hyaluronate-iodine complex for wound healing.

Hyaluronate-iodine complex is a wound healing adjuvant approved for use in the European Union. The objective of this study is to validate hyaluronate-iodine as a potential wound healing agent. Patients were recruited from the hospital, the outpatient clinic, and the wound healing center. Hyaluronate-iodine soaked gauze was applied to wounds either daily or every other day depending on the amount of wound exudate. Wounds were measured weekly, and progression was documented with digital photography. All wounds were debrided as needed using standard surgical techniques. Fourteen patients (19 wounds) were entered into this prospective study, and 10 patients completed treatment. Fourteen wounds progressed to complete healing with a mean healing time of 18.1 ± 15.1 weeks. Treatment was interrupted in four patients. One patient discontinued treatment due to pain related to application of hyaluronate-iodine, another patient for transportation issues, and the other two patients were lost to follow-up due to relocation out of state and noncompliance with scheduled appointments. Hyaluronate-iodine was helpful in the healing of all types of wounds treated in this pilot study. The antiadhesive and antimicrobial properties of hyaluronate-iodine create a desirable environment conducive to wound healing without apparent detrimental effects.

Decreased use of computed tomography with a modified clinical scoring system in diagnosis of pediatric acute appendicitis.

HYPOTHESIS: Use of a modified clinical grading score improves accuracy in diagnosing acute appendicitis in the pediatric population while decreasing the use of computed tomography (CT). DESIGN: Retrospective medical records review after approval by the institutional review board. We determined the Alvarado score for each patient and correlated it with the pathological findings and imaging studies to evaluate the efficacy of CT and its attendant radiation exposure. SETTING: Community teaching hospital. PATIENTS: Sixty-one patients, aged 3 to 16 years, admitted with suspected acute appendicitis. MAIN OUTCOME MEASURES: Sensitivity, specificity, and accuracy of the modified Alvarado scoring system. RESULTS: The standard Alvarado score for acute appendicitis had a sensitivity of 92% and a specificity of 82%, with an accuracy of 92%. In the modified Alvarado scoring system, CT findings were substituted for Alvarado scores in the ranges of 5 or 6, 5 to 7, 5 to 8, and 5 to 9. The modification resulted in the greatest accuracy (98%) in diagnosing appendicitis in patients with scores in the range of 5 to 7. This modification theoretically would have decreased the use of CT by about 27% in this group of retrospectively studied patients. Furthermore, in patients with Alvarado scores of 1 to 4, another diagnosis should be considered; in patients with scores of 5 to 7, CT should be performed; and, in patients with scores of 8 to 10, an appendectomy should be performed promptly without further studies. CONCLUSIONS: The modified Alvarado score is useful as an aid in diagnosing acute appendicitis in the pediatric population. This scoring system eliminates unnecessary use of CT and the attendant potential cancer-inducing radiation in the pediatric population.

Traumatic innominate artery pseudoaneurysm in the setting of a bovine arch.

Blunt traumatic injury of the innominate artery occurs infrequently but is commonly lethal. Bovine aortic arch anatomy is a predisposition to this injury. Clinical findings, chest X-ray, and computerized tomography may suggest the diagnosis, and it may be confirmed with angiography. Both interposition and bypass grafting are operative repair methods of choice. EEG monitoring confirms cerebral perfusion, thereby allowing the deferment of shunts and cardiovascular bypass with hypothermic arrest. We report a case of traumatic innominate artery pseudoaneurysm in the setting of "bovine aortic arch" anatomy, together with multiple associated injuries, including descending aorta transection. We also review the current literature on the topic.

Is gender related to the stage of colorectal cancer at initial presentation in young patients?

BACKGROUND: The incidence of colorectal cancer (CRC) in young adults is rising, and young age is a predictor of poor survival. The purpose of this study was to examine factors leading to increased mortality in patients ≤ 50 years of age, and to examine this population for characteristics that could lead to benefit from CRC screening. METHODS: Charts of patients 50 years of age and under, diagnosed with CRC from 1998 through 2007, at our community teaching hospital, were reviewed retrospectively. Demographics, social and family history, staging, treatment and death were evaluated. Mann Whitney, Fisher Exact, and χ(2) tests were used with P <0.05 considered statistically significant. RESULTS: Forty-five young patients with CRC were identified. Twenty-five patients were female and 20 male; the mean age was 43.6 y. Most patients presented with rectal bleeding. Right-sided cancers had a higher presenting stage (P < 0.05). Men had both a higher presenting stage (P = 0.35) and a higher incidence of smoking compared with women (P = 0.001). Female patients were more likely to have left-sided CRC (65%) compared with men (35%). Ninety-six percent of patients underwent surgical resection; 14 patients died. CONCLUSIONS: CRC in young adults is not common, but is often advanced when discovered. Diagnostic efforts should be aggressive in young patients who have rectal bleeding, especially young male smokers. Sigmoidoscopy is not adequate for comprehensive diagnosis of CRC in young patients, as the majority have right-sided colon cancers, which often result in subsequent presentation of the disease at a higher stage, risk, and mortality rate.