Motor and non-motor features of Parkinson's disease in LRRK2 G2019S carriers versus matched controls

INTRODUCTION

LRRK2 G2019S mutation carriers with Parkinson's disease (PD) have been generally indistinguishable from those with idiopathic PD, with the exception of variable differences in some motor and non-motor domains, including cognition, gait, and balance. LRRK2 G2019S is amongst the most common genetic etiologies for PD, particularly in Ashkenazi Jewish (AJ) populations.

METHODS

This cross-sectional data collection study sought to clarify the phenotype of LRRK2 G2019S mutation carriers with PD. Primary endpoints were the Movement Disorder Society Unified Parkinson Disease Rating Scale (MDS-UPDRS) and Montreal Cognitive Assessment (MoCA). Other motor and non-motor data were also assessed. The Mann-Whitney U Test was utilized to compare LRRK2 G2019S carriers with PD (LRRK2+) with non-carrier PD controls who were matched for age, gender, education, and PD duration. Survival analyses and log rank tests were utilized to compare interval from onset of PD to development of motor and non-motor complications.

RESULTS

We screened 251 subjects and 231 completed the study, of whom 9 were LRRK2+, including 7 AJ subjects. 22.73% of AJ subjects with a family history of PD (FH) and 12.96% of AJ subjects without a FH were LRRK2+. There were no significant differences between the 9 LRRK2+ subjects and 19 matched PD controls in MDS-UPDRS, MoCA, or other motor and non-motor endpoints.

CONCLUSION

Prevalence of the LRRK2 G2019S mutation in AJ and non-AJ subjects in our study population in Cleveland, Ohio was comparable to other clinical studies. There were no significant motor or non-motor differences between LRRK2+ PD and matched PD controls.

Impact of a Preclinical Medical Student Anesthesiology Elective on the Attitudes and Perceptions of Medical Students Regarding Anesthesiology

Purpose

First- and second-year medical students typically have limited exposure to the field of anesthesiology, yet recent match data shows growing interest in the specialty. Early, structured exposure to anesthesiology in the form of a preclinical elective may allow medical students to make more informed decisions on their specialty of choice.

Methods

The anesthesiology preclinical elective, BIOL 6704: "Anesthesia: Much More than Putting you to Sleep", is a one-credit course taught at The Warren Alpert Medical School of Brown University. A survey consisting of fifteen questions assessing changes in attitudes, perceptions, and interest in anesthesiology was distributed to first- and second-year medical students before and after course participation. The results were analyzed using the Wilcoxon's signed-rank test for paired samples.

Results

The biggest impact of the preclinical elective was observed in the students' subjective understanding of key aspects of the practice of anesthesiology. Statistically significant improvement was seen in the understanding of airway management, anesthetic pharmacology, basics of ultrasound, vascular access, anesthesiology subspecialties, and an understanding of anesthesiology residency. Overall, results were limited by our small sample size.

Conclusion

Our elective allows medical students to explore anesthesiology early in their medical school career. After taking this course, students noted more familiarity with various topics in anesthesiology. Peer institutions lacking a similar course may consider using our experience to increase interest about the specialty of anesthesiology for future students.

Hypercapnia during transcatheter aortic valve replacement under monitored anaesthesia care: a retrospective cohort study

BACKGROUND

Acute intraoperative hypercapnia and respiratory acidosis, which can occur during monitored anaesthesia care (MAC), pose significant cardiopulmonary risks for patients with aortic stenosis undergoing transcatheter aortic valve replacement (TAVR). The goal of the present study is to assess the incidence, risk factors and impact of intraoperative hypercapnia during MAC for patients undergoing transfemoral TAVR.

METHODS

Data was collected retrospectively from the electronic medical record of 201 consecutive patients with available intraoperative arterial blood gas (ABG) data who underwent percutaneous transfemoral TAVR with MAC using propofol and dexmedetomidine. ABGs (pH, arterial partial pressure of carbon dioxide (PaCO2) and arterial partial pressure of oxygen) were performed at the start of each case (baseline), immediately prior to valve deployment (ValveDepl), and on arrival to the postanaesthesia care unit. Data was analysed using Fisher's exact test, unpaired Student's t-test, Wilcoxon rank sum or univariate linear regression as appropriate based on PaCO2 and pH during ValveDepl (PaCO2-ValveDepl, pH-ValveDepl) and change in PaCO2 and pH from baseline to ValveDepl (PaCO2-%increase, pH-%decrease) to determine their association with preoperative demographic data, intraoperative anaesthetic and vasoactive medications and postoperative outcomes.

RESULTS

PaCO2 increased by a mean of 28.4% and was higher than baseline in 91% of patients. Younger age, male sex, increased weight and increased propofol dose contributed to higher PaCO2-ValveDepl and greater PaCO2-%increase. Patients with PaCO2-ValveDepl>60 mm Hg, pH≤7.2 and greater pH-%decrease were more likely to receive vasoactive medications, but perioperative PaCO2 and pH were not associated with adverse postoperative outcomes.

CONCLUSIONS

Transient significant hypercapnia commonly occurs during transfemoral TAVR with deep sedation using propofol and dexmedetomidine. Although the incidence of postoperative outcomes does not appear to be affected by hypercapnia, the need for vasopressors and inotropes is increased. If deep sedation is required for TAVR, hypercapnia and the need for haemodynamic and ventilatory support should be anticipated.