Consequences of contextual factors on clinical reasoning in resident physicians

Context specificity and the impact that contextual factors have on the complex process of clinical reasoning is poorly understood. Using situated cognition as the theoretical framework, our aim was to evaluate the verbalized clinical reasoning processes of resident physicians in order to describe what impact the presence of contextual factors have on their clinical reasoning. Participants viewed three video recorded clinical encounters portraying straightforward diagnoses in internal medicine with select patient contextual factors modified. After watching each video recording, participants completed a think-aloud protocol. Transcripts from the think-aloud protocols were analyzed using a constant comparative approach. After iterative coding, utterances were analyzed for emergent themes with utterances grouped into categories, themes and subthemes. Ten residents participated in the study with saturation reached during analysis. Participants universally acknowledged the presence of contextual factors in the video recordings. Four categories emerged as a consequence of the contextual factors: (1) emotional reactions (2) behavioral inferences (3) optimizing the doctor patient relationship and (4) difficulty with closure of the clinical encounter. The presence of contextual factors may impact clinical reasoning performance in resident physicians. When confronted with the presence of contextual factors in a clinical scenario, residents experienced difficulty with closure of the encounter, exhibited as diagnostic uncertainty. This finding raises important questions about the relationship between contextual factors and clinical reasoning activities and how this relationship might influence the cost effectiveness of care. This study also provides insight into how the phenomena of context specificity may be explained using situated cognition theory.

Abstract 1843: Novel actions of next-generation taxanes benefit advanced stages of prostate cancer

Purpose: To improve the outcomes of patients with castrate resistant prostate cancer (CRPC), there is an urgent need for more effective therapies and approaches that individual specific treatments for patients with CRPC. The current studies compared the novel taxane, cabazitaxel with the previous generation docetaxel, and aimed to determine which tumors are most likely to respond.

Experimental design: Cabazitaxel (CBTX) and docetaxel (DCTX) were compared via in vitro modeling to determine molecular mechanism, biochemical and cell biological impact, and cell proliferation, which was further assessed ex vivo in human tumor explants. Isogenic pairs of RB knockdown and control cells were interrogated in vitro, and in xenograft tumors for cabazitaxel response.

Results: The data herein show that i. CBTX exerts stronger cytostatic and cytotoxic response compared to DCTX, especially in CRPC; ii. CBTX induces aberrant mitosis, leading to pyknotic and multinucleated cells; iii. taxanes do not act through the androgen receptor (AR); iv. Gene expression profiling reveals distinct molecular actions for CBTX v. tumors that have progressed to castration resistance via loss of RB show enhanced sensitivity to CBTX.

Conclusions: CBTX not only induces improved cytostatic and cytotoxic effects, but also impacts distinct molecular pathways, compared to DCTX, which could underlie its efficacy after DCTX treatment has failed in CRPC patients. Finally, RB is identified as the first potential biomarker that could define the therapeutic response to taxanes in metastatic CRPC. This would suggest that loss of RB function induces sensitization taxanes, which could benefit up to 50% of CRPC cases.

Citation Format: Renee de Leeuw, Lisa Berman-Booty, Matthew Schiewer, Stephen Ciment, Robert Den, Adam Dicker, William Kelly, Edouard Trabulsi, Costas Lallas, Leonard Gomella, Karen Knudsen. Novel actions of next-generation taxanes benefit advanced stages of prostate cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1843. doi:10.1158/1538-7445.AM2015-1843

Relationship of Neuroimaging to Typical Sleep Times During a Clinical Reasoning Task: A Pilot Study

Background: Sleep deprivation and fatigue have been associated with medical errors, clinical performance decrements, and reduced quality of life for both practicing physicians and medical students. Greater understanding of the impact of sleep quantity on clinical reasoning could improve patient care. The purpose of our pilot study was to examine relationships between clinical reasoning (assessed by functional magnetic resonance imaging) and sleep time (measured in different ways by actigraphy) while answering multiple-choice questions (MCQs) from licensing agencies. Methods: Residents and faculty were administered a clinical reasoning exercise (MCQs from licensing bodies) during functional magnetic resonance imaging. Usual sleep patterns were sampled with actigraphy. Covariate analysis was used to examine the relationship between sleep duration (mean sleep, minimum sleep, maximum sleep) and brain activity during clinical reasoning (solving MCQs from licensing bodies). Results: The mean sleep time over the duration of monitoring for the group was 7.19 hours (SD 0.66) with a range of 6.1 to 8.1 hours (internal medicine faculty 7.1 hours, SD 0.41; internal medicine residents 7.27 hours, SD 0.92). There was a negative relationship between activation in the prefrontal cortex and minimum sleep time while reflecting on MCQs. Conclusion: Our findings provide evidence that the quantity of sleep can modulate brain activity while completing a clinically meaningful task that should be confirmed in larger studies. Our findings suggest that the construct of sleepiness may be more complex than appreciated by many and that the most important of these sleep measures in terms of outcomes remains to be determined.

Asthma in pregnancy: Physiology, diagnosis, and management

Asthma is a common, potentially serious, medical condition that affects an estimated 8% of pregnant patients, with 4% of all pregnant patients experiencing an exacerbation in the past year. Practitioners must be able to diagnose, educate, and treat such patients as they undergo significant physiological and immunologic change. But staying current can be challenging given over 3000 citations for "asthma and pregnancy" in a recent PubMed search, with 750 described as review articles. Patients have even more difficulty navigating information, with 29 million Google search results for this same query and 1.2 million alone for the question whether asthma medications are safe during pregnancy. This review provides brief answers to important management questions followed by supporting background literature.

Experimental characterization of next-generation expanded-bed adsorbents for capture of a recombinant protein expressed in high-cell-density yeast fermentation

Expanded-bed adsorption (EBA) can be particularly useful in protein recovery from high-cell-density fermentation broth where conventional methods for harvest and clarification, such as continuous centrifugation and depth filtration, demand long processing times and are associated with high costs. In this work, the use of next-generation high-particle-density EBA adsorbents, including two mixed-mode resins, for the direct capture of a recombinant protein expressed in yeast at high cell densities is evaluated. Using classical experimental approaches and under different conditions (pH, salt, etc.), Langmuir isotherm parameters for these resins are obtained along with pore diffusivity values. Additional batch adsorption studies with Fastline® MabDirect, the resin that demonstrated the highest static binding capacity for the recombinant protein of interest under the conditions evaluated in this study, indicate competitive binding of nontarget proteins and approximately a 30% reduction in equilibrium binding capacity to 50 mg/mL settled bed in the presence of a 5%-10% cell concentration. Packed-bed (PB) dynamic binding capacities for the MabDirect resin (25-40 mg/mL PB) were significantly higher than for the Fastline® HSA resin and for the MabDirect MM resin in expanded-bed mode (5-10 mg/mL settled bed). Bed expansion behavior for the mMabDirect MM resin along with process yield and eluate purity are identified as a function of linear velocity and cell density, demonstrating process feasibility for pilot scale use.

Abstract TP26: Enterprise ™ -assisted Recanalization in Acute Ischemic Stroke (ERAIS): First FDA approved prospective trial

AIM: The ERAIS study was designed to test the safety of the Enterprise stent as the primary intraarterial device in cerebral revascularization.

METHODS: Twenty patients with acute ischemic stroke within 8 hours of stroke symptom onset with contraindication to IV thrombolysis or with no clinical improvement 1 hour after administration of IV thrombolysis were prospectively enrolled between July 2010 and June 2012 after consultation with the local IRB and FDA. The Enterprise stent was deployed across the occlusion. Alternatively, the stent was used as a thrombectomy device based on operator preference.

RESULTS: All patients had major intracranial vessel occlusion (TIMI 0), with an average preoperative NIHSS score of 15.5±1.3. The primary target vessels where the stents were deployed were the MCA in 15 patients, ICA in 2, basilar artery in 2 and tandem ICA-MCA in 1.The stent was deployed in 13 patients and used as a thrombectomy device and thus retrieved in 7 patients. Twenty-four stents were used in 20 patients. The time from start of procedure to TIMI 2/3 recanalization was 43±21 minutes. Recanalization to TIMI 2/3 flow was achieved in 18 (90%) of 20 patients. Three major complications were noted (15%), including 2 MIs and 1 ischemic stroke in a distribution other than the qualifying vessel. Eight minor complications were noted. Seven (35%) patients died within 30 days of revascularization. Ten patients (50%) improved to an mRS score of 0-2 within 30 days post-intervention.

CONCLUSION: The Enterprise stent is equivalent in efficiency and has comparable acceptable adverse events when compared to previously published results with the Wingspan stent in the SARIS trial and confirms the high recanalization rate achieved with stent-assisted revascularization in selected patients. This is the first reported prospective FDA-approved trial with the Enterprise stent as the primary intraarterial stroke revascularization device.

Tips for preparing for a 340B integrity audit

Key action steps hospitals and health systems can take to prepare for a 340B Drug Pricing Program integrity audit include the following: Conduct mock audits. Develop policies and procedures that specifically address the issues of patient eligibility, duplicate discounts, and appropriate Medicaid billing. Create a multidisciplinary team for 340B program oversight.

Comparing a script concordance examination to a multiple-choice examination on a core internal medicine clerkship

BACKGROUND

Script concordance (SC) questions, in which a learner is given a brief clinical scenario then asked if additional information makes one hypothesis more or less likely, with answers compared to a panel of experts, are designed to reflect a learner's clinical reasoning.

PURPOSE

The purpose is to compare reliability, validity, and learner satisfaction between a three-option modified SC examination to a multiple-choice question (MCQ) examination among medical students during a 3rd-year internal medicine clerkship, to compare reliability and learner satisfaction of SC between medical students and a convenience sample of house staff, and to compare learner satisfaction with SC between 1st- and 4th-quarter medical students.

METHODS

Using a prospective cohort design, we compared the reliability of 20-item SC and MCQ examinations, sequentially administered on the same day. To measure validity, scores were compared to scores on the National Board of Medical Examiners (NBME) subject examination in medicine and to a clinical performance measure. SC and MCQ were also administered to a convenience sample of internal medicine house staff. Medical student and house staff were anonymously surveyed regarding satisfaction with the examinations.

RESULTS

There were 163 students who completed the examinations. With students, the initial reliability of the SC was half that of MCQ (KR20 0.19 vs. 0.41), but with house staff (n = 15), reliability was the same (KR20 = 0.52 for both examinations). SC performance correlated with student clinical performance, whereas MCQ did not (r = .22, p = .005 vs. .11, p = .159). Students reported that SC questions were no more difficult and were answered more quickly than MCQ questions. Both exams were considered easier than NBME, and all 3 were considered equally fair. More students preferred MCQ over SC (55.8% vs. 18.0%), whereas house staff preferred SC (46% vs. 23%; p = .03).

CONCLUSIONS

This SC examination was feasible and was more valid than the MCQ examination because of better correlation with clinical performance, despite being initially less reliable and less preferred by students. SC was more reliable and preferred when administered to house staff.

What does a good lifestyle mean to you? Perspectives of 4th-year U.S. medical students with military service obligations in 2009

BACKGROUND

A specialties' lifestyle is known to be important for specialty selection, but how medical students define this concept is unknown.

PURPOSE

The aim of this article is to determine how 4th-year medical students perceive lifestyle of specialties.

METHODS

All 4th-year U.S. medical students graduating in 2009 with a military service obligation were invited to participate in an electronic survey. Responses to an open-ended question, "When someone says 'That specialty has a good lifestyle,' what does that mean to you?" were classified into themes by a consensus of the authors and then compared to the students' selected specialty.

RESULTS

Response rate for the questionnaire was 46% (369 of 797). Four themes describing lifestyle emerged: "schedule control" (67% of students), "off time" (53%), "financial aspects" (48%), and "work life" (26%).

CONCLUSIONS

Medical students' definition of a "good lifestyle" includes four themes, which should be used in future research of the lifestyle factor of specialty selection.

A method for the objective study of tool-using behavior

Key pecking for food was shaped in four crows within a conventional operant-conditioning test chamber. When pecking stabilized, a metal screen with openings 2.5 cm high by 1.0 cm wide, was placed over the response key, so that the crow could still see but could no longer peck the key. At the same time, several dozen wooden matchsticks, which could be used to operate the key, were placed in the test chamber. The crows made no use of these during 50 to 75 hr of exposure to this condition. Subsequently, the behavior of two crows was shaped so that they approached the matchsticks, picked one up in their beaks, approached the response key with the matchstick in their beak, and finally operated the response key by poking the matchstick through the screen. This shaping procedure was ineffective with the two other crows. However, these birds were successfully trained through positional fading of the tool. This involved suspending a metal rod from the ceiling so that it hung directly in front of the response key, and the crow had only to peck it to operate the key. Then, the rod was gradually lowered by lengthening its tether until it eventually rested on the floor of the test chamber. The principal advantage of this methodology is the automatic recording of the terminal (tool-using) behavior under study.

Responding under positive and negative response contingencies in pigeons and crows

Four crows were trained to key peck for food. Then, they were exposed to a positive response contingency that required them to peck the key when it was illuminated briefly (the trial) in order to receive food. This procedure resulted in consistent within-trial pecking. When the contingency changed so that food was presented at the end of a trial when no response occurred, but the trial terminated immediately and food was omitted when a response occurred (negative response contingency), responding decreased markedly. Eight pigeons were studied under the same change in contingencies. These birds varied in their response histories from naive to having several years' experience. The previously naive pigeons also showed rapid declines in responding under the negative contingency; the responding of the birds with extended training histories declined much more slowly. Eventually, however, six of the eight pigeons showed little or no responding under the negative contingency, while they responded consistently when re-exposed to the positive contingency. These findings question the power and the generality of the negative automaintenance phenomenon.

AUTOMATIC IDENTIFICATION AND DELINEATION OF GERM LAYER COMPONENTS IN H&E STAINED IMAGES OF TERATOMAS DERIVED FROM HUMAN AND NONHUMAN PRIMATE EMBRYONIC STEM CELLS

We present a methodology for the automatic identification and delineation of germ-layer components in H&E stained images of teratomas derived from human and nonhuman primate embryonic stem cells. A knowledge and understanding of the biology of these cells may lead to advances in tissue regeneration and repair, the treatment of genetic and developmental syndromes, and drug testing and discovery. As a teratoma is a chaotic organization of tissues derived from the three primary embryonic germ layers, H&E teratoma images often present multiple tissues, each of having complex and unpredictable positions, shapes, and appearance with respect to each individual tissue as well as with respect to other tissues. While visual identification of these tissues is time-consuming, it is surprisingly accurate, indicating that there exist enough visual cues to accomplish the task. We propose automatic identification and delineation of these tissues by mimicking these visual cues. We use pixel-based classification, resulting in an encouraging range of classification accuracies from 74.9% to 93.2% for 2- to 5-tissue classification experiments at different scales.