Comparison of a Valveless Trocar System and Conventional Insufflation in Pediatric Urologic Surgery.

Background: Conventional operative insufflation uses a one-way trocar to handle instruments while maintaining pneumoperitoneum. In 2007, the AirSeal® valveless trocar insufflation system was introduced, which maintains stable pneumoperitoneum while continuously evacuating smoke. Although this device has been validated in adult patients, it has not been extensively validated in the pediatric population. Materials and Methods: A retrospective cohort study of pediatric urology patients aged 0 to 21 who underwent laparoscopic pyeloplasty between March 2016 and October 2021 was performed. Intraoperative physiologic parameters, procedure characteristics, postoperative outcomes, and demographics of each patient in whom either AirSeal insufflation system (AIS) or conventional insufflation system (CIS) was utilized were obtained from hospital records. Data were compared across the AIS and CIS cohorts. The primary outcomes were intraoperative anesthetic and physiologic parameters, including end tidal carbon dioxide, oxygen saturation, body temperature, positive inspiratory pressure, systolic blood pressure, and heart rate. Results: There were no significant differences in the anesthetic and physiologic parameters in the AIS and CIS groups. In addition, no differences in demographics, procedural characteristics, or complication rates were found between the cohorts. Conclusion: The AirSeal valveless trocar insufflation system demonstrates comparable intraoperative anesthetic and physiologic outcomes compared to conventional one-way valve insufflation in pediatric laparoscopic pyeloplasty. Certain surgeon-related qualitative metrics are underappreciated in this study, however, including improved visualization with vigorous suctioning and pressure maintenance with frequent instrument exchanges. Surgeon experience may mask the benefits of these characteristics as it pertains to quantitative surgical outcomes such as estimated blood loss, operative time, and perioperative complications.

Behavior modification after inactivation of cerebellar dentate nuclei.

Effort-based decision making occurs when subjects are given a choice between a reward available at a high response cost and a reward available at a low response cost and is altered in individuals with disorders such as autism or particular patterns of brain injury. The current study explored the relationship between effort-based decision making and reinforcement characteristics in the T maze. This was done using both normal animals and animals with bilateral inactivation of the cerebellar dentate nuclei. Rats chose between alternatives in which one arm contained high-density reinforcement (HR) and the other arm contained low-density reinforcement (LR). During training, the HR arm was obstructed and the point at which the animal no longer worked for reinforcement (breaking point) was determined. The cerebellar dentate nuclei were then transiently inactivated and once again breaking points were assessed. The results indicated that inactivation of the dentate nucleus disrupted effort-based decision making. Additionally, altering both the palatability and the magnitude of the reinforcement were assessed in an attempt to reestablish the original preinactivation breaking point. It was hypothesized that an increase in the strength or magnitude of the reinforcement would promote an increase in the breaking point of the animal even when the cerebellum was inactivated. The results indicated that with both strategies animals effectively reestablished original breaking points. The results of this study will inform the current literature regarding the modification of behavior after brain injury and further the understanding of the behavioral deficits associated with cerebellar dysfunction.