The Effect of Commonly Used Local Anesthetic on Bacterial Growth.

INTRODUCTION: Liposomal bupivacaine (LB) has emerged as a superior form of local anesthetic across numerous surgical subspecialties. The purpose of this study is to evaluate the ex-vivo antimicrobial effects of LB in comparison with traditional local anesthetics. METHODS: A standardized inoculum of bacteria commonly associated with surgical site infection was inoculated into a suspension of 1% lidocaine, 0.25% bupivacaine, Exparel (proprietary liposomally packaged 1.3% bupivacaine), and normal saline as a growth control. RESULTS: In all five bacteria tested, the medium inoculated with traditional local anesthetics reduced growth to a greater degree than LB-inoculated plates. Both conventional local anesthetics reduced the growth of all bacteria when compared with the control with the exception of methicillin-susceptible Staphylococcus aureus growth in bupivacaine. LB-inoculated plates had equivalent growth to the control in all plates with the exception of Escherichia coli plates which demonstrated superior growth. CONCLUSIONS: The results of this simple ex-vivo model suggest that the liposomal packaging of bupivacaine may decrease this local anesthetic's innate antibacterial properties.

Reducing colorectal surgical site infections: a novel, resident-driven, quality initiative.

BACKGROUND: Surgical site infections (SSIs) cause significant patient morbidity and increase costs. This work prospectively examines our institutional effort to reduce SSIs through a resident-driven quality initiative. METHODS: A general surgery resident-championed, evidenced-based care bundle for patients undergoing colorectal surgery at a single academic institution was developed using attending mentorship. National Surgical Quality Improvement Program definitions for SSIs were used. Data were collected prospectively and bundle compliance was monitored using a checklist. The primary outcome compared SSIs before and after implementation. RESULTS: In the 2 years preceding standardization, 489 colorectal surgery cases were performed. SSIs occurred in 68 patients (13.9% SSI rate). Following implementation of the bundle, 212 cases were performed with 10 SSIs (4.7% SSI rate, P < .01). Multivariate logistic regression analysis found a decrease in superficial and overall SSIs (odds ratio .17, 95% confidence interval .05 to .59; odds ratio .31, 95% confidence interval .14 to .68). CONCLUSIONS: These data demonstrate that resident-driven initiatives to improve quality of care can be a swift and effective way to enact change. We observed significantly decreased SSIs with a renewed focus on evidence-based, standardized patient care.

Evaluation of the validity of medical students' self-assessments of proficiency in clinical simulations.

BACKGROUND: The accuracy of self-assessments has not been well supported in the literature. This study was undertaken to examine the validity of medical students' ratings of their proficiency during encounters with simulated patients and simulation devices. METHODS: Confidential self-assessments for 10 skills were collected from 195 students during a formal clinical skills assessment related to 3 cases at the end of a surgery clerkship. The cases required students to gather data from simulated patients and perform procedures such as rectal examinations, nasogastric tube insertions, and suturing on bench simulation models. The patients were trained to assess student performance. RESULTS: There were significant differences between student self-assessments and simulated patient scores for general clinical skills as opposed to procedural skills. Students' mean self-assessments in the data gathering and interpersonal skills were 2-6 % points higher than ratings of their proficiency by simulated patients. However, self-assessments on procedures were 5-8 points lower than patient ratings. The median correlation between self-assessments and patient ratings for general clinical skills such as data gathering and interpersonal skills was 0.08 (not significant), whereas the median correlation between student and patient ratings in procedures was 0.22 (P < 0.01). CONCLUSIONS: Third-year medical students' self-assessments for specific procedures are more valid than self-assessments of general clinical skills. Students are less confident in their procedural skills compared with general clinical skills. Although self-assessments should not be used as the sole measure of performance in clinical simulations, self-assessments for specific procedures can provide supplemental information on proficiency.

Anastomotic leaks after colorectal anastomosis occurring more than 30 days postoperatively: a single-institution evaluation.

National hospital registries only report colorectal anastomotic leaks (ALs) within 30 days postoperatively. The aim of our study was to determine the incidence and significance of ALs that occur beyond 30 days postoperatively. We performed a retrospective review of our prospective database from June 2008 to August 2012. A total of 504 patients were included. These patients were operated on by two surgeons. Any clinical or radiographic abnormalities were considered to be an anastomotic imperfection. A total of 504 patients were reviewed with a total of 18 (3.6%) anastomotic leaks. Six leaks (31.6% of leaks) were diagnosed more than 30 days postoperatively (P < 0.001). Of the 18 leaks, interventional radiology drainage was performed for four cases and 14 patients required reoperation. All six delayed leaks required reoperation. There was one leak that occurred under 30 days, which was discovered on autopsy. The median follow-up was 12 months (range, 1 to 4 months). All the delayed leak patients presented with fistulas, whereas 58 per cent of typical leak patients presented with the triad of leukocytosis, fever, and abdominal pain. Colorectal anastomotic leaks can occur after the 30-day postoperative period. In patients with vague and atypical abdominal findings, anastomotic leak must be suspected. More systematic, prospective studies are required to help us further understand the risk factors and natural history of anastomotic failures in elective colorectal surgery.

American Society of Anesthesiologists class and Charlson's comorbidity index as predictors of postoperative colorectal anastomotic leak: a single-institution experience.

BACKGROUND: The American Society of Anesthesiologists (ASA) physical status classification and Charlson comorbidity index (CCI) was adopted to assess patients' physical condition before surgery. Studies suggest that ASA score and CCI might be a prognostic criterion (indicator) for patient outcome. The aim of this study is to determine if ASA classification and CCI can determine the risk of anastomotic leaks (AL) in patients who underwent colorectal surgery. METHODS: A retrospective analysis of 505 consecutive colorectal resections with primary anastomoses between 2008 and 2012 was performed at a university hospital. ASA score, CCI, surgical procedure, length of stay, age, body mass index (BMI), comorbidities, and postoperative outcomes were analyzed. RESULTS: Two hundred sixty-five patients had an ASA score of I and II, 227 patients had an ASA score of III, and 13 patients had an ASA score of IV. A total of 19 patients had an anastomotic leak (ASA I-II: 5 patients, 1.9%; ASA III: 12 patients, 5.58%; ASA IV: 2 patients, 18.18%). A higher ASA score was significantly associated with AL on further analysis (OR: 2.99, 95% CI: 1.345-6.670, P = 0.007). When matched for age, BMI, and CCI on logistic regression analysis, increased ASA level was independently related to an increased likelihood of leak (OR(steroids) = 14.35, P < 0.01; OR(ASA_III v I-II) = 2.02, P = 0.18; OR(ASA_IVvI-II) = 8.45, P = 0.03). There were no statistically significant differences in means between the leak and no-leak patients with respect to age (60.69 versus 65.43, P = 0.17), BMI (28.03 versus 28.96, P = 0.46), and CCI (6.19 versus 7.58, P = 0.09). CONCLUSIONS: ASA score, but not CCI, is independently associated with anastomotic leak. Patients with a high ASA class should be closely followed postoperatively for AL after colorectal operations.

A novel approach to assessing technical competence of colorectal surgery residents: the development and evaluation of the Colorectal Objective Structured Assessment of Technical Skill (COSATS).

OBJECTIVE: To develop and evaluate an objective method of technical skills assessment for graduating subspecialists in colorectal (CR) surgery-the Colorectal Objective Structured Assessment of Technical Skill (COSATS). BACKGROUND: It may be reasonable for the public to assume that surgeons certified as competent have had their technical skills assessed. However, technical skill, despite being the hallmark of a surgeon, is not directly assessed at the time of certification by surgical boards. METHODS: A procedure-based, multistation technical skills examination was developed to reflect a sample of the range of skills necessary for CR surgical practice. These consisted of bench, virtual reality, and cadaveric models. Reliability and construct validity were evaluated by comparing 10 graduating CR residents with 10 graduating general surgery (GS) residents from across North America. Expert CR surgeons, blinded to level of training, evaluated performance using a task-specific checklist and a global rating scale. The mean global rating score was used as the overall examination score and a passing score was set at "borderline competent for CR practice." RESULTS: The global rating scale demonstrated acceptable interstation reliability (0.69) for a homogeneous group of examinees. Both the overall checklist and global rating scores effectively discriminated between CR and GS residents (P < 0.01), with 27% of the variance attributed to level of training. Nine CR residents but only 3 GS residents were deemed competent. CONCLUSIONS: The Colorectal Objective Structured Assessment of Technical Skill effectively discriminated between CR and GS residents. With further validation, the Colorectal Objective Structured Assessment of Technical Skill could be incorporated into the colorectal board examination where it would be the first attempt of a surgical specialty to formally assess technical skill at the time of certification.

Psychometrics of the scale of attitudes toward physician-pharmacist collaboration: a study with medical students.

BACKGROUND: Despite the emphasis placed on interdisciplinary education and interprofessional collaboration between physicians and pharmacologists, no psychometrically sound instrument is available to measure attitudes toward collaborative relationships. AIM: This study was designed to examine psychometrics of an instrument for measuring attitudes toward physician-pharmacist collaborative relationships for administration to students in medical and pharmacy schools and to physicians and pharmacists. METHODS: The Scale of Attitudes Toward Physician-Pharmacist Collaboration was completed by 210 students at Jefferson Medical College. Factor analysis and correlational methods were used to examine psychometrics of the instrument. RESULTS: Consistent with the conceptual framework of interprofessional collaboration, three underlying constructs, namely "responsibility and accountability;" "shared authority;" and "interdisciplinary education" emerged from the factor analysis of the instrument providing support for its construct validity. The reliability coefficient alpha for the instrument was 0.90. The instrument's criterion-related validity coefficient with scores of a validated instrument (Jefferson Scale of Attitudes Toward Physician-Nurse Collaboration) was 0.70. CONCLUSIONS: Findings provide support for the validity and reliability of the instrument for medical students. The instrument has the potential to be used for the evaluation of interdisciplinary education in medical and pharmacy schools, and for the evaluation of patient outcomes resulting from collaborative physician-pharmacist relationships.

Technical skills acquisition in surgery-bound senior medical students: an evaluation of student assertiveness.

OBJECTIVE: To prepare students pursuing surgical careers, we devised a senior subinternship curriculum supplement that focused on the acquisition of technical skills required of surgical residents. We hypothesized that more assertive students, those that accomplished more of the curriculum, would perform better on a technical skills Objective Structured Clinical Examination (OSCE). DESIGN: Senior medical students rotating on their first general surgery subinternship were administered a 6-station OSCE on the first day of their subinternship and again during the final week of the month-long rotation. A self-directed, 38-task "scavenger hunt" representing common intern level clinical skills, procedures, and patient care activities was provided to each student. SETTING: The study was performed at Jefferson Medical College, a large, private medical school in Philadelphia, PA. PARTICIPANTS: Forty-nine senior students completed surgical subinternships between July 2009 and September 2010, and participated both in the pre-/post-OSCEs and the scavenger hunt. RESULTS: Students performed significantly better on the post-rotation OSCE than on the pre-rotation OSCE; 70.2% ± 8.1% vs. 60.4% ± 12.0%, p < 0.0001. Assertiveness scores from the "scavenger hunt" did not correlate with final OSCE scores (r = -0.328, p = 0.25), and were negatively correlated with the change between pre- and post-OSCE scores (r = -0.573, p < 0.04). Individual student assertiveness scores were determined by the number of tasks completed over the course of the rotation. CONCLUSIONS: As surgical education becomes more streamlined with evolving work hour restrictions, medical school education is playing an increasingly pivotal role in preparing students for internship. In our study, individual assertiveness in completing structured self-directed learning tasks did not directly predict the acquisition of proficiency in technical skills. We feel assertiveness is overshadowed by other factors that may carry more weight in terms of technical skills acquisition. Further studies are required to delineate these factors and ultimately enhance technical skills acquisition during medical school.

Evaluation of the use of patient-focused simulation for student assessment in a surgery clerkship.

BACKGROUND: The purpose of this study was to evaluate the use of simulated patients in conjunction with anatomic and tissue task-training models to assess skills. METHODS: Faculty reviewed the objectives of the clerkship to identify skills to be acquired. Three cases were developed related to rectal examination, suturing, and inserting intravenous lines and nasogastric tubes. Student scores were based on their ability to gather data from simulated patients and perform procedures on simulation models. RESULTS: A total of 670 students were assessed between 2006 and 2009. Alpha reliability coefficients were .97 for Communication/Interpersonal Skills, .71 for Procedures, and .58 for Data Gathering. Students receiving low ratings from faculty in the clerkship had significantly (P < .001) lower simulation scores. There were significant (P < .001) relationships between scores and grades in other clerkships. CONCLUSIONS: The combination of simulated patients and simulation models yielded reliable scores for procedural and interpersonal skills, and evidence of validity related to clinical ratings.

Survivin-induced Aurora-B kinase activation: A mechanism by which APC mutations contribute to increased mitoses during colon cancer development.

APC mutations initiate most colorectal cancers (CRCs), but cellular mechanisms linking this to CRC pathology are unclear. We reported that wild-type APC in the colon down-regulates the anti-apoptotic protein survivin, and APC mutation up-regulates it, explaining why most CRCs display survivin overexpression and apoptosis inhibition. However, it does not explain another hallmark of CRC pathology--increased mitotic figures and cell proliferation. Because survivin activates aurora-B kinase (ABK) in vitro, catalyzing mitosis, we hypothesized that in normal colonic crypts, APC controls ABK activity, while in neoplastic APC-mutant crypts, ABK activity is up-regulated, increasing mitosis. We quantitatively mapped intracryptal distributions of survivin, ABK, and markers of activated downstream signaling and mitosis (INCENP, phospho-histone-H3, phospho-centromere-protein-A). In normal crypts, gradients for these markers, ABK:survivin:INCENP complexes, and ABK activity were highest in the lower crypt (inverse to the APC gradient). In neoplastic crypts that harbor APC mutations, proliferating (Ki-67+) cells and cells expressing survivin, ABK, and phospho-histone-H3 were distributed farther up the crypt. Hence, as cells migrate up neoplastic crypts, transitions between cell phenotypes (eg, from stem to proliferating) appear delayed. In CRC cell lines, increasing wild-type APC, inhibiting TCF-4, or decreasing survivin expression down-regulated ABK activity. Thus, APC mutation-induced up-regulation of the survivin/ABK cascade can explain delayed crypt cell maturation, expansion of proliferative cell populations (including mitotic figures), and promotion of colon tumorigenesis.

Anastomotic leak rate after low anterior resection for rectal cancer after chemoradiation therapy.

Anastomotic leak may be the most concerning complication after colorectal anastomosis. To compare open with laparoscopic rectal resection, we must have accurate leak rates in patients who have received neoadjuvant chemoradiation therapy to serve as a benchmark for comparison. All patients who had preoperative chemoradiation therapy with rectal resection and low pelvic anastomosis for cancer in a single colorectal practice over a 7-year period were retrospectively reviewed. All patients had proximal diversion and a contrast enema study before stoma reversal. Eighty-seven consecutive patients were included in the study. Average age was 58 years. Fifty-nine per cent of patients were male. Sixty-six per cent were smokers. Pathologic T stage was 5 per cent T0, 16 per cent T1, 28 per cent T2, 47 per cent T3, and 5 per cent T4. Seventy-five per cent of patients were pathologically lymph node-negative. Average time to stoma reversal was 122 days. Total anastomotic leak rate was 10.3 per cent (8% clinical leaks). Five (56%) patients with leak successfully underwent reversal of their diverting stoma (average time to reversal, 290 days). Patients who had the complication of anastomotic leakage had less likelihood of stoma reversal and a significantly prolonged time to stoma reversal.

Outcomes of low anterior resection anastomotic leak after preoperative chemoradiation therapy for rectal cancer.

Anastomotic leak remains a major cause of morbidity and mortality after colorectal surgery, especially with low anastomoses. The aim of this study was to assess outcomes of patients who developed an anastomotic leak after low anterior resection of the rectum for rectal cancer. An Institutional Review Board-approved retrospective review of 89 consecutive patients undergoing open low anterior resection with primary anastomosis for cancer of the mid/lower rectum at a single institution between January 2001 and December 2008 was performed. All patients received neoadjuvant chemotherapy and radiation therapy. Proximal diversion was performed in all patients. Perioperative data were collected and analyzed with attention to management and outcomes after development of anastomotic leak. Nine patients (10.1%) developed anastomotic leak. Mean age was 62 years. Mean tumor level was 4.8 cm above the anal verge. Symptomatic anastomotic leak developed in seven (78%) patients. Percutaneous drainage was performed in five (55.6%) patients with an average of 4.4 procedures required for management of anastomotic leak. Five (55.6%) patients required reoperation. Only two procedures (25%) involved laparotomy. No operative procedures were performed emergently. There were no mortalities. Excluding one patient who received completion proctectomy for local recurrence, restoration of intestinal continuity was achieved in five (63%) of eight patients. Mean time to stoma closure was 289 days. The potentially lethal complication of anastomotic leak after low anterior resection for rectal cancer can be managed expectantly and electively in patients who are proximally diverted with the expectation of stoma reversal in the long term.

The devil is in the third year: a longitudinal study of erosion of empathy in medical school.

PURPOSE: This longitudinal study was designed to examine changes in medical students' empathy during medical school and to determine when the most significant changes occur. METHOD: Four hundred fifty-six students who entered Jefferson Medical College in 2002 (n = 227) and 2004 (n = 229) completed the Jefferson Scale of Physician Empathy at five different times: at entry into medical school on orientation day and subsequently at the end of each academic year. Statistical analyses were performed for the entire cohort, as well as for the "matched" cohort (participants who identified themselves at all five test administrations) and the "unmatched" cohort (participants who did not identify themselves in all five test administrations). RESULTS: Statistical analyses showed that empathy scores did not change significantly during the first two years of medical school. However, a significant decline in empathy scores was observed at the end of the third year which persisted until graduation. Findings were similar for the matched cohort (n = 121) and for the rest of the sample (unmatched cohort, n = 335). Patterns of decline in empathy scores were similar for men and women and across specialties. CONCLUSIONS: It is concluded that a significant decline in empathy occurs during the third year of medical school. It is ironic that the erosion of empathy occurs during a time when the curriculum is shifting toward patient-care activities; this is when empathy is most essential. Implications for retaining and enhancing empathy are discussed.