Hi, everyone. My name is Nikita LaCompkin. I'm one of the recent graduates of the Mount Sinai School of Medicine. I really want to thank the scientific committee for giving us the opportunity to present this work. I want to talk a little bit about the safety and feasibility of neuro-oncology surgeries in the ambulatory surgery setting and present some preliminary data from a national multicenter series. We have no disclosures. So ambulatory surgery centers were initially designed to serve as alternatives to hospital outpatient services, and the vast majority of these are certified by Medicare, and there are over 5,000 of these in the United States. And about 90% have at least some partial physician ownership, although this varies by site. And as time has gone on, a lot of different surgical subspecialties have taken advantage of these sites. As you can see here, orthopedics, ophthalmology, even medical subspecialties like GI. And a lot of these surgical proceduralists predominate in the center of multispecialty Medicare certified ASCs. As time has gone on, there's been a tremendous growth in the use of these in a lot of different fields driven by specialties like interventional cardiology, as well as spine surgery, both orthopedics and neurosurgery. As you can see, even in a three-year window between 2015 and 2018, the proportion of cases done by each specialty has really grown dramatically. And there are a lot of reasons for this, most notably the numerous cost advantages offered by these. And this is for both payers as well as patients. For payers, governments such as Medicare and Medicaid, as well as private insurers, the reimbursement rates for ASCs are substantially lower. So just as an example, for pacemaker implants, the reimbursement by Medicare is about $3,721 in ASC versus over $7,000 in a hospital and over $14,000 for inpatients. And analyses done by the CMS really emphasize this, showing that if ASCs continue to grow as a proportion of market share, there will be billions of dollars in savings. From the patient's perspective, a lot of studies have shown that patients are more satisfied, both due to the lower costs, which are a product of the lower reimbursement rates, but also the convenience and not needing to travel. Here you can see one of the studies that was done on this, on ASCs in the United States in 2006, and they really emphasized that patients undergoing care here had substantially lower wait times, which contributed to their satisfaction. So initially, these were really designed to have simple procedures done, but over time, the complexity of the types of cases being done here has grown dramatically. Just as an example, in 2019 and last year, CMS actually authorized 12 cardiac cath codes to be performed at ASCs, as well as the recommendation to add total and partial hip replacement. These are the CPT codes for the cardiac caths. So what does this have to do with neurosurgery? Because the case complexity has increased in ASCs that become more predominant and safer, a lot of studies have looked at neurosurgical populations taking advantage of these, most notably in spine. Here's some studies out of Vanderbilt that I was actually a part of looking at lumbar decompression patients, as well as patients undergoing ACDF. And really, the primary question is how to take the next step away from just identifying does risk factor X predict complication Y, but really identifying the types of patients who may benefit from a certain intervention or a certain treatment site. And neuro-oncology is a really interesting field for this due to its incredible heterogeneity. A lot of people, when they think of neuro-oncology, think of really complex skull-based operations, OZs, far laterals for foramen magnum and angiomas. But a lot of community neurosurgery does simpler brain tumor cases. For example, simple craniotomies for cortical METs, minimally invasive options like LIT that have recently taken off. And there's a lot of potential to look at whether there's a subset of these patients that can benefit from taking advantage of ASCs. And a couple of studies have set this precedent, this one by the group in Toronto in JNS, showing that a number of their patients were able to safely undergo general anesthesia and be discharged without complications overall for their cohort. These findings have been corroborated by other groups, also published in JNS here, combining brain biopsy patients with those undergoing craniotomy for tumor, again highlighting that this can be done safely in carefully selected patients, and I really emphasize that part. This is a paper in Red Journal looking at their outpatient series combining both spine surgery as well as craniotomies and biopsies for tumor. So the main question we had was whether this relationship between treatment site, ACS, and subsequent outcomes in patients held true in a large multicenter series. And the next question we had was which patients, in terms of comorbidity burden, would be best suited for this? And we sought to identify a cutoff for these patients. So we performed a retrospective analysis of a prospectively collected multicenter registry obtained by the ACS. And over the course of two years, we identified all adult patients undergoing craniotomy for the resection of a meningioma or a glioma, both high and low grade. We collected a wide array of variables, demographics, perioperative variables, comorbidities, as well as various outcomes for this group. We did exclude patients undergoing complex skull-based surgeries, CP angle, posterior fossa, et cetera. And we used the comorbidities to compute the modified Charleston Comorbidity Index in order to quantify the comorbidity burden for each patient. Our primary outcomes of interest were mortality within 30 days, major complications, as well as minor complications. And the subset for each of these can be seen here. We performed a fairly typical statistical approach. We used chi-squared or Fisher's exact tests to explore the differences between inpatient and outpatient cohorts for each of our outcome metrics of interest. And then we used binary multivariable logistic regression analysis to assess outpatient surgery as a risk factor for adverse events. And then we performed an ROC curve analysis to identify the CCI score beyond which these patients experience increased rates of adverse events. So we performed three regressions and three ROC curve analyses. So we had 3,671 patients with data, 148 of whom underwent surgery on an outpatient basis, and 3,526 of which were inpatients. For each of our outcomes of interest, mortality, major complications, minor complications, patients undergoing surgery on an outpatient basis had decreased incidence of these compared to their inpatient counterparts. When we look at the regression data, modified CCI was significantly associated with mortality. You can see here, while the site of care, so undergoing surgery on an inpatient basis, was not significantly associated. And this remained true for both major complications as well as minor complications. When we performed the ROC curve analysis, we found that a CCI of three was the ideal cutoff that maximized specificity and sensitivity for each of the three outcome metrics of interest. So this study has a number of limitations. This is a retrospective review, so there's always an inherent risk for selection bias. When you use a registry like this, you're really limited in terms of the variables you can use. And there are some key variables that we cannot extract and use in our analysis, most notably the location of the lesion. Where was the glioma? Where was the meningioma? And this is key as it really impacts the surgical approach and the consequent risk of adverse events. And all the adverse events are only collected within 30 days of surgery by the ACS. And thus we couldn't account for the likely numerous complications that would take place after this. So overall, carefully selected brain tumor patients may be able to safely undergo resection at ACSs. Comorbidity burden for these data was the primary predictor of suboptimal outcomes. Patients with a CCI below three may be most suitable for safe outpatient treatment. Thank you very much.

Neuro-oncology surgeries

Ambulatory surgery centers

Safety and feasibility

ASC utilization

Comorbidity burden