Association of Residents' Neural Signatures With Stress Resilience During Surgery.

Importance: Intraoperative stressors may compound cognitive load, prompting performance decline and threatening patient safety. However, not all surgeons cope equally well with stress, and the disparity between performance stability and decline under high cognitive demand may be characterized by differences in activation within brain areas associated with attention and concentration such as the prefrontal cortex (PFC). Objective: To compare PFC activation between surgeons demonstrating stable performance under temporal stress with those exhibiting stress-related performance decline. Design, Setting, and Participants: Cohort study conducted from July 2015 to September 2016 at the Imperial College Healthcare National Health Service Trust, England. One hundred two surgical residents (postgraduate year 1 and greater) were invited to participate, of which 33 agreed to partake. Exposures: Participants performed a laparoscopic suturing task under 2 conditions: self-paced (SP; without time-per-knot restrictions), and time pressure (TP; 2-minute per knot time restriction). Main Outcomes and Measures: A composite deterioration score was computed based on between-condition differences in task performance metrics (task progression score [arbitrary units], error score [millimeters], leak volume [milliliters], and knot tensile strength [newtons]). Based on the composite score, quartiles were computed reflecting performance stability (quartile 1 [Q1]) and decline (quartile 4 [Q4]). Changes in PFC oxygenated hemoglobin concentration (HbO2) measured at 24 different locations using functional near-infrared spectroscopy were compared between Q1 and Q4. Secondary outcomes included subjective workload (Surgical Task Load Index) and heart rate. Results: Of the 33 participants, the median age was 33 years, the range was 29 to 56 years, and 27 were men (82%). The Q1 residents demonstrated task-induced increases in HbO2 across the bilateral ventrolateral PFC (VLPFC) and right dorsolateral PFC in the SP condition and in the VLPFC in the TP condition. In contrast, Q4 residents demonstrated decreases in HbO2 in both conditions. The magnitude of PFC activation (change in HbO2) was significantly greater in Q1 than Q4 across the bilateral VLPFC during both SP (mean [SD] left VLPFC: Q1, 0.44 [1.30] µM; Q4, -0.21 [2.05] µM; P < .001; right VLPFC: Q1, 0.46 [1.12] µM; Q4, -0.15 [2.14] µM; P < .001) and TP (mean [SD] left VLPFC: Q1, 0.44 [1.36] µM; Q4, -0.03 [1.83] µM; P = .001; right VLPFC: Q1, 0.49 [1.70] µM; Q4, -0.32 [2.00] µM; P < .001) conditions. There were no significant between-group differences in Surgical Task Load Index or heart rate in either condition. Conclusions and Relevance: Performance stability within TP is associated with sustained prefrontal activation indicative of preserved attention and concentration, whereas performance decline is associated with prefrontal deactivation that may represent task disengagement.

A decade of imaging surgeons' brain function (part II): A systematic review of applications for technical and nontechnical skills assessment.

BACKGROUND: Functional neuroimaging technologies enable assessment of operator brain function and can deepen our understanding of skills learning, ergonomic optima, and cognitive processes in surgeons. Although there has been a critical mass of data detailing surgeons' brain function, this literature has not been reviewed systematically. METHODS: A systematic search of original neuroimaging studies assessing surgeons' brain function and published up until November 2016 was conducted using Medline, Embase, and PsycINFO databases. RESULTS: Twenty-seven studies fulfilled the inclusion criteria, including 3 feasibility studies, 14 studies exploring the neural correlates of technical skill acquisition, and the remainder investigating brain function in the context of intraoperative decision-making (n = 1), neurofeedback training (n = 1), robot-assisted technology (n = 5), and surgical teaching (n = 3). Early stages of learning open surgical tasks (knot-tying) are characterized by prefrontal cortical activation, which subsequently attenuates with deliberate practice. However, with complex laparoscopic skills (intracorporeal suturing), prefrontal cortical engagement requires substantial training, and attenuation occurs over a longer time course, after years of refinement. Neurofeedback and interventions that improve neural efficiency may enhance technical performance and skills learning. CONCLUSION: Imaging surgeons' brain function has identified neural signatures of expertise that might help inform objective assessment and selection processes. Interventions that improve neural efficiency may target skill-specific brain regions and augment surgical performance.

A decade of imaging surgeons' brain function (part I): Terminology, techniques, and clinical translation.

BACKGROUND: Functional neuroimaging has the potential to deepen our understanding of technical and nontechnical skill acquisition in surgeons, particularly as established assessment tools leave unanswered questions about inter-operator differences in ability that seem independent of experience. METHODS: In this first of a 2-part article, we aim to utilize our experience in neuroimaging surgeons to orientate the nonspecialist reader to the principles of brain imaging. Terminology commonly used in brain imaging research is explained, placing emphasis on the "activation response" to an surgical task and its effect on local cortical hemodynamic parameters (neurovascular coupling). RESULTS: Skills learning and subsequent consolidation and refinement through practice lead to reorganization of the functional architecture of the brain (known as "neuroplasticity"), evidenced by changes in the strength of regional activation as well as alterations in connectivity between brain regions, culminating in more efficient use of neural resources during task performance. CONCLUSION: Currently available neuroimaging techniques that either directly (ie, measure electrical activity) or indirectly (ie, measure tissue hemodynamics) assess brain function are discussed. Finally, we highlight the important practical considerations when conducting brain imaging research in surgeons.