Hemispheric activation differences in novice and expert clinicians during clinical decision making.

Clinical decision making requires knowledge, experience and analytical/non-analytical types of decision processes. As clinicians progress from novice to expert, research indicates decision-making becomes less reliant on foundational biomedical knowledge and more on previous experience. In this study, we investigated how knowledge and experience were reflected in terms of differences in neural areas of activation. Novice and expert clinicians diagnosed simple or complex (easy, hard) cases while functional magnetic resonance imaging (fMRI) data were collected. Our results highlight key differences in the neural areas activated in novices and experts during the clinical decision-making process. fMRI data were collected from ten second year medical students (novices) and ten practicing gastroenterologists (experts) while they diagnosed sixteen (eight easy and eight hard) clinical cases via multiple-choice questions. Behavioral data were collected for diagnostic accuracy (correct/incorrect diagnosis) and time taken to assign a clinical diagnosis. Two analyses were performed with the fMRI data. First, data from easy and hard cases were compared within respective groups (easy > hard, hard > easy). Second, neural differences between novices and experts (novice > expert, expert > novice) were assessed. Experts correctly diagnosed more cases than novices and made their diagnoses faster than novices on both easy and hard cases (all p's < 0.05). Time taken to diagnose hard cases took significantly longer for both novices and experts. While similar neural areas were activated in both novices and experts during the decision making process, we identified significant hemispheric activation differences between novice and expert clinicians when diagnosing hard clinical cases. Specifically, novice clinicians had greater activations in the left anterior temporal cortex and left ventral lateral prefrontal cortex whereas expert clinicians had greater activations in the right dorsal lateral, right ventral lateral, and right parietal cortex. Hemispheric differences in activation were not observed between novices and experts while diagnosing easy clinical cases. While clinical decision-making engaged the prefrontal cortex (PFC) in both novices and experts, interestingly we observed expertise related differences in the regions and hemispheres of PFC activation between these groups for hard clinical cases. Specifically, in novices we observed activations in left hemisphere neural regions associated with factual rule-based knowledge, whereas in experts we observed right hemisphere activation in neural regions associated with experiential knowledge. Importantly, at the neural level, our data highlight differences in so called type 2 clinical decision-making processes related to prior knowledge and experience.

Working memory, reasoning, and expertise in medicine-insights into their relationship using functional neuroimaging.

Clinical reasoning is dependent upon working memory (WM). More precisely, during the clinical reasoning process stored information within long-term memory is brought into WM to facilitate the internal deliberation that affords a clinician the ability to reason through a case. In the present study, we examined the relationship between clinical reasoning and WM while participants read clinical cases with functional magnetic resonance imaging (fMRI). More specifically, we examined the impact of clinical case difficulty (easy, hard) and clinician level of expertise (2nd year medical students, senior gastroenterologists) on neural activity within regions of cortex associated with WM (i.e., the prefrontal cortex) during the reasoning process. fMRI was used to scan ten second-year medical students and ten practicing gastroenterologists while they reasoned through sixteen clinical cases [eight straight forward (easy) and eight complex (hard)] during a single 1-h scanning session. Within-group analyses contrasted the easy and hard cases which were then subsequently utilized for a between-group analysis to examine effects of expertise (novice > expert, expert > novice). Reading clinical cases evoked multiple neural activations in occipital, prefrontal, parietal, and temporal cortical regions in both groups. Importantly, increased activation in the prefrontal cortex in novices for both easy and hard clinical cases suggests novices utilize WM more so than experts during clinical reasoning. We found that clinician level of expertise elicited differential activation of regions of the human prefrontal cortex associated with WM during clinical reasoning. This suggests there is an important relationship between clinical reasoning and human WM. As such, we suggest future models of clinical reasoning take into account that the use of WM is not consistent throughout all clinical reasoning tasks, and that memory structure may be utilized differently based on level of expertise.

Esophageal Cooling for Hypoxic Ischemic Encephalopathy: A Feasibility Study.

Targeted temperature management (TTM) is a recognized treatment to decrease mortality and improve neurological function in hypoxic ischemic encephalopathy. An esophageal cooling device (ECD) has been studied in animal models, but human data are limited. An ECD appears to offer similar benefits to intravascular cooling catheters, with potentially less risk to the patient. We studied whether the ECD could act as a substitute for intravascular cooling catheters in delivering adequate TTM after cardiac arrest. Nine patients admitted to the intensive care unit after cardiac arrest who required TTM were enrolled prospectively. The primary outcome measures were timeliness of insertion, ease of insertion, user Likert ratings, time to achieve a target temperature of 36°C, and time during which target temperature was maintained within 1°C of the 36°C goal for 24 hours by using an ECD. Time to reach target temperature was 0 to 540 minutes (mean: 113.33 minutes, median: 0 minute, standard deviation [SD]: 179.22). Maintenance of a target temperature of 36°C over 24 hours had a range of 58.33% to 100% (mean: 91.67%, median: 95.83%, SD: 13.34). Ease of insertion related to Likert ratings with a range of 1-9 (mean: 5.38, median: 5.5, SD: 3.43) and a simplicity of ECD uses a range of 4-10 (mean: 7.63, median: 8.0, SD: 1.65). Overall, there was preference for the ECD over intravascular cooling methods (mean: 6.71, mean: 6, SD: 3.01) and external cooling methods (mean: 8.0, median: 9.0, SD: 2.33). For patients requiring TTM, use of an ECD adequately allowed for TTM goals to be achieved and maintained. Overall, user evaluation was positive.

Early Mobilization of Mechanically Ventilated Patients.

Critically ill patients requiring mechanical ventilation are least likely to be mobilized and, as a result, are at-risk for prolonged complications from weakness. The use of bed rest and sedation when caring for mechanically ventilated patients is likely shaped by historical practice; however, this review demonstrates early mobilization, with little to no sedation, is possible and safe. Assessing readiness for mobilization in context of progressing patients from passive to active activities can lead to long-term benefits and has been achievable with resource-efficient implementations and team work.