High-volume Tertiary Care Center Research Articles

Evaluation of quality of non-mydriatic fundus images obtained with non-contact TrueColor, confocal scanner during third phase of nationwide lockdown

Aims: This study aims to evaluate the non-mydriatic fundus image quality obtained with a confocal fundus device. Also, to evaluate the influence of non-mydriatic pupil size on image quality. Settings and Design: A cross-sectional study was conducted in the outpatient department of a high-volume tertiary eye care centre in South India during the third phase of the COVID-19 lockdown. Subjects and Methods: 831 consenting, consecutive patients (1539 eyes) were photographed from May 5 to May 17, 2020, and were graded excellent, fair, adequate, or inadequate; based on white noise, black noise, and image acquisition signals. Pupil diameters were obtained with light-emitting diode flash technology. Statistical Analysis: The collected data were analyzed using SPSS software. Descriptive statistics in the form of frequencies and percentages were calculated. Simple (univariate) linear regression analysis and adjusted regression analysis were used to establish the relationship between pupil size and fundus photo quality. Results: The quality of the fundus photo was excellent in 70.12% (n = 1079), fair in 15.72% (n = 242), adequate in 5.78% (n = 89), and inadequate in 8.38% (n = 129). Of the 1410 obtained images (subtracting the inadequate quality images), 87.66% (n = 1236) were normal and 12.34% (n = 174) were pathological. There was a positive linear relationship between pupil size and quality of retinal photograph; OS (R2 = 0.935) had a slightly better association than OD (R2 = 0.901). Conclusions: The majority of the confocal images were excellent in quality. Our four-point grading system serves as a reliable measure of non-mydriatic photograph quality. Pupil size is a significant predictor of image quality for non-mydriatic photographs in surveillance programs.

In vitro fertilization as an independent risk factor for perinatal complications: Single-center 10 years cohort study.

Assisted Reproductive Technology (ART) has made great strides in the past forty-years, but no medical treatment comes without side effects. Despite several studies reporting high incidences of perinatal complications, the association is inconclusive. Also, the effect of racially and ethnically distinguished Asian population undergoing ART on perinatal outcomes is not well studied. Therefore, this study attempts to compare various perinatal outcome parameters in ART, and spontaneously conceived singleton pregnancies from a single high-volume tertiary care center. This is a retrospective cohort study from a single tertiary infertility center, carried out from January 2011 to September 2020. The study included 1,125 IVF conceived babies (AB group) and 7,193 spontaneous conceived babies (SB group). The groups were compared using the Pearson Chi-square test and adjusted odds ratio, calculated using the multivariate analysis. Most of the perinatal complications, such as preterm birth (PTB), early preterm birth, low birth weight (LBW), extremely low birth weight, small for gestational age, large for gestational age babies, neonatal intensive care unit (NICU) admission, need for surfactant, meconium aspiration syndrome, neonatal seizures, intraventricular hemorrhage, hypoxic-ischemic encephalopathy, and patent ductus arteriosus was significantly increased in the AB group when compared to the SB group (p<0.05). In-vitro fertilization (IVF) independently increases the risk of LBW (aOR 2.530; 95% CI 2.194-2.917), PTB (aOR 4.004; 95% CI 3.496-4.587), NICU admission (aOR 2.003; 95% CI 1.610-2.492) and neonatal seizures (aOR 9.805; 95% CI 5.755-16.706).Conclusions: All ART-conceived pregnant patients should receive antenatal counselling regarding perinatal complications and should deliver at a tertiary care center with appropriate NICU support.

Surgical neonates with coronavirus infectious disease-19 infection: An experience with five cases at high-volume tertiary care centre of India.

Coronavirus infectious disease-19 (COVID-19) has caused serious threat to global health. With progression of time, more and more cases are being reported in paediatric age group. Management of COVID-19-positive neonates with surgical condition is challenging as apart from medical management of COVID-19-induced morbidities, they also require surgical intervention. Various guidelines have been proposed for the management of neonates with coronavirus infection and surgical pathologies. In this original article, we are sharing our experience in managing such neonates. We managed five neonates with different surgical pathologies who were positive for the coronavirus at the time of admission. They received medical management initially. Three of these five neonates were operated after they were negative for the virus. The remaining two patients were operated in positive state due to their condition requiring urgent surgical intervention. All the recommendations as per the COVID-19 protocol were followed. Four of these babies survived. One neonate with the diagnosis of gastroschisis expired during stay in designated COVID-19 neonatal intensive care unit. Authors conclude that COVID-19-positive status of neonates should not scare the health-care workers. COVID-19 positivity in neonates does not alter the outcome.

775 Impact of frailty on medium-term follow-up in patients undergoing transcatheter aortic valve implantation in a high flow referral centre with high volumes

Abstract Aims Transcatheter strategies to treat aortic stenosis (AS) are an established therapeutic option in older patients not candidate for open heart surgery. Guidelines recommend the adoption of surgical scores like the Society of Thoracic Surgeons (STS) as tools for risk stratification. However, these scores may have limited predictive value in older patients. To assess the impact of frailty status on a composite endpoint comprising all-cause death and cardiovascular (CV) events in patients with severe AS evaluated for transcatheter aortic valve implantation (TAVI) in a high-flow and high-volume tertiary care centre. Methods and results Consecutive patients &amp;gt;80 years referred to TAVI from January to December 2019 at our institution were screened for frailty through a comprehensive geriatric assessment (CGA) based on physical function and the multidimensional prognostic index (MPI). Physical function was evaluated by the short physical performance battery (SPPB), a tool exploring balance, gait speed, strength and endurance that produces a score ranging from 0 to 12 (lowest to highest performance). The SPPB &amp;lt;6 is an established strong predictor of mortality and disability. The MPI is a three-level score used to stratify risk of mortality (low, intermediate, or high risk) based on eight key domains for frailty assessment (functional and cognitive status, nutrition, mobility and risk of pressure sores, multimorbidity, polypharmacy, and co-habitation). Data on mortality and CV events at 6 and 12 months were retrieved via administrative records and/or telephone follow-up. Overall, 134 patients were referred for TAVI (mean age: 84 ± 4 years; &amp;gt;90 years: 12%, women 67%). The STS risk score was 4.6 ± 3.0 (low risk: 49%; intermediate: 39%, high risk: 12%). Mean SPPB was 6.3 ± 3.7 (SPPB &amp;lt;6: 32%). Ninety-five (71%) patients belonged to the MPI-low risk group, 30 (22%) to the MPI intermediate risk group and nine (7%) to the MPI high risk group. SPPB and MPI scores were moderately correlated with STS (Spearman correlation coefficient: SPPB R = 0.31, P = 0.01, MPI R = 0.29, P = 0.03, Figure 1A and B). At 1 year, 3 (2.2%) patients died, and 11 (8.2%) were hospitalized for CV events: major bleeding, N = 6(4.5%); stroke: N = 4 (3.0%); re-do: N = 1 (0.7%). The probability of the composite endpoint was higher for patients at intermediate/high MPI risk (HR intermediate/high risk vs. low risk: HR: 2.9, 95% CI: 1.1–6.8, P = 0.031, Figure 1C), while no association with STS (P = 0.332) was found. Conclusions In a prospective cohort of TAVI candidates, frailty stratified short- and medium-term prognosis. The integrated frailty assessment could be a useful tool for early detection of patients at risk of disability, and potentially, for preventing the futility of the TAVI procedure. 120 Figure

Effect of the SARS-CoV-2 Pandemic on the Experience and Outcomes of Patients Who Underwent Resection for Pancreatic Cancer at a High-volume Tertiary Care Center

Effect of the SARS-CoV-2 Pandemic on the Experience and Outcomes of Patients Who Underwent Resection for Pancreatic Cancer at a High-volume Tertiary Care Center

Effect of an Emergency Endovascular Aneurysm Repair Protocol on Ruptured Abdominal Aortic Aneurysm Mortality: A Single-Center Retrospective Review

We have demonstrated an emergency endovascular aneurysm repair (EVAR) protocol in a high-volume tertiary care center reduces mortality for patients with ruptured infrarenal abdominal aortic aneurysms (rAAAs).

Impact of frailty status on medium-term follow up in patients undergoing percutaneous transcatheter aortic valve implantation in a high-flow referral center with high procedural volumes

Abstract Background Transcatheter strategies to treat aortic stenosis (AS) are an established therapeutic option in older patients not candidate for open heart surgery. Current guidelines recommend the adoption of surgical scores like the Society of Thoracic Surgeons (STS) as tools for risk stratification. However, these scores may have limited predictive value in older patients. Purpose To assess the impact of frailty status on a composite endpoint comprising mortality and cardiovascular (CV) events in patients with severe AS evaluated for transcatheter aortic valve implantation (TAVI) in a high-flow and high-volume tertiary care center. Methods Consecutive patients &amp;gt;80 years referred to TAVI from January to December 2019 at our tertiary care institution were prospectively screened for frailty through a comprehensive geriatric assessment (CGA) based on physical function and the Multidimensional Prognostic Index (MPI). Physical function was evaluated by the Short Physical Performance Battery (SPPB), a tool exploring balance, gait speed, strength and endurance that produces a score ranging from 0 to 12 (lowest to highest performance). The SPPB &amp;lt;6 is an established strong predictor of mortality and disability. The MPI is a three-level score used to stratify risk of mortality (low, intermediate or high risk) based on eight key domains for frailty assessment (functional and cognitive status, nutrition, mobility and risk of pressure sores, multimorbidity, polypharmacy and co-habitation). Data on mortality and CV events at 6 and 12 months were retrieved via administrative records and/or telephone follow-up. Results Overall, 134 patients were referred for TAVI (mean age: 84±4 years; &amp;gt;90 years: 12%, women 67%). The average STS risk score was 4.6±3.0 (low risk: 49%; intermediate: 39%, high risk: 12%). Mean SPPB was 6.3±3.7 (SPPB &amp;lt;6: 32%). Ninety-five (71%) patients belonged to the MPI-low risk group, 30 (22%) to the MPI intermediate risk group and nine (7%) to the MPI high risk group. SPPB and MPI scores were moderately correlated with STS (Spearman correlation coefficient: SPPB R=0.31, p=0.01, MPI R=0.29, p=0.03, Figure Panel A and B). At 12 months, 3 (2.2%) patients died, and 11 (8.2%) were hospitalized for CV events: major bleeding, N=6 (4.5%); stroke: N=4 (3.0%); re-do: N=1 (0.7%). The probability of the composite endpoint was higher for patients at intermediate/high MPI risk (HR intermediate/high risk vs low risk: HR 2.9, 95% CI 1.1–6.8, p=0.031, Figure 1 Panel C), while no association with STS (p=0.332) was found. Conclusions In a prospectively enrolled cohort of TAVI candidates, frailty indices stratified short- and medium-term prognosis. The integrated frailty assessment could be a useful tool for early detection of patients at risk of disability, and potentially, for preventing the futility of the TAVI procedure. Funding Acknowledgement Type of funding sources: None. Figure 1

S3274 Comparison of Referral Patterns and Indications for High Resolution Manometry Between High Volume and Low Volume Tertiary Care Centers

S3274 Comparison of Referral Patterns and Indications for High Resolution Manometry Between High Volume and Low Volume Tertiary Care Centers

Learning curve analysis of single-port robot-assisted extraperitoneal prostatectomy using the cumulative sum (CUSUM) method.

Single-port (SP) was recently implemented as an alternative robotic system for extraperitoneal radical prostatectomy (EPP). The primary aim of this study is to characterize the learning curve (LC) for the SP-EPP for an experienced multi-port (MP) robotic surgeon. All consecutive SP-EPP cases (N=150) performed by a single surgeon from initial experience in a high-volume tertiary care center were prospectively included. The cumulative sum Method (CUSUM) was used retrospectively to create the LCs for SP-EPP surgery based on several outcomes used to gauge the surgeon's performance relative to those previously obtained with the current gold standard (MP-Robot Assisted Radical Prostatectomy (MP-RALP);N=80). The evaluation of a surgical transition from MP to SP prostatectomy analyzed with the Statistical Process Control and the CUSUM method revealed a smooth and safe LC divided into four phases of 30-40 cases and a decrease of surgical time, blood loss and postoperative complication rate after the first learning phase.

Biliary Complications Following Adult Deceased Donor Liver Transplantation: Risk Factors and Implications at a High-volume US Center.

Background.Biliary leaks and anastomotic strictures comprise the majority of biliary complications (BCs) following liver transplantation (LT). Currently, there are few large contemporary case series of BCs in adult deceased donor liver transplant (DDLT) recipients in the literature. The purpose of this study was to examine the pretransplant and intraoperative risk factors associated with BCs at a high-volume tertiary care center and determine the impact of these BCs on their posttransplant course and long-term transplant outcomes.Methods.We retrospectively reviewed all adult patients undergoing a DDLT from a donor after brain death (DBD) at Emory University between January 2015 and December 2019.Results.A total of 647 adult patients underwent DDLT from a DBD during the study period and were included in analyses. The median length of follow-up posttransplant was 2.5 y. There were a total of 27 bile leaks (4.2%) and 69 biliary strictures (10.7%). Recipient age and cold ischemic time were identified as risk factors for biliary leak, whereas alcoholic cirrhosis as transplant indication was a risk factor for biliary stricture. Placement of a biliary stent was associated with the development of both biliary leaks and anastomotic strictures. Posttransplant, biliary leaks were a significant risk factor for future episodes of acute rejection but did not impact overall survival. In contrast, biliary strictures were associated with a significantly reduced overall survival at 1- and 4-y post DDLT.Conclusions.BCs are a major source of morbidity and mortality following DDLT, with strictures and leaks associated with distinct posttransplant complications.

Identifying Best Practices for Managing Internal Carotid Artery Injury During Endoscopic Endonasal Surgery by Consensus of Expert Opinion.

Injury to the internal carotid artery (ICA) is a potentially devastating complication of endoscopic endonasal surgery (EES) that as many as 20% of skull base surgeons will experience at least once during their careers. Managing these injuries is difficult given the small operative field and poor visibility created by high-flow hemorrhage, and, at present, there is no consensus regarding best practices. This study seeks to consolidate the practices and opinions of experienced skull base surgeons from high-volume tertiary care centers into a single consensus statement regarding the best practices for managing ICA injuries during EES. A panel of 23 skull base surgeons (15 neurosurgeons and 8 otolaryngologists) completed a 3-round Delphi survey that assessed experiences and opinions regarding various aspects of ICA injury management. Mean (SD) years since fellowship completion was 15.6 (8.1) and all but 3 surgeons had experienced an ICA injury at least once. The final consensus statement included 36 guidelines all of which were grouped under 1 of 4 categories: 11 statements concerned preoperative management and equipment for high-risk patients; 14 statements concerned hemorrhage control; 4 statements concerned definitive management; 7 statements concerned pharmacologic treatment, blood pressure, and neurophysiologic monitoring. There are numerous decisions that a surgeon must make when facing a carotid artery injury. In our estimation, many questions can be grouped under 1 of the 4 categories outlined in our consensus statement and can be addressed by these findings.

Pattern of injuries in blunt trauma abdomen: A retrospective evaluation of imaging findings at a high-volume tertiary care trauma centre

Objective: Contrast-enhanced computed tomography (CECT) is the investigation of choice in trauma patients. The purpose of this study was to retrospectively evaluate the pattern, severity and association of abdominal injuries based on imaging at a high-volume tertiary trauma care centre. Methods: Retrospective evaluation of the CT records of patients over a period of 5 years was done at our institute. A total of 1519 patients who had undergone contrast-enhanced abdominal CT at a 64-slice Multidetector CT for abdominal trauma were included in this study. Inclusion criteria were: 1) History of blunt abdominal trauma, 2) Patients who had undergone a biphasic CECT abdomen scan. Exclusion criteria were: 1) Patients with penetrating injury, 2) Patients with incomplete data set/records. Results: Liver was the most common injured organ in both adult (38.8%) and paediatric population (40.9%). Significant higher incidence of mesenteric injury, bladder injury, spinal and rib fractures were seen in adult patients. Significant association of anorectal injuries (P=0.003) and bladder/urethral injuries with pelvic fractures was also seen (P&lt;0.001). Conclusion: Our study provided important insights about the pattern, severity and association between the various abdominal injuries based on imaging findings in a large patient population. Larger studies with incorporation of clinical outcome in such patients can help in formulating appropriate management strategies.

Machine Learning Models to Predict Major Adverse Cardiovascular Events After Orthotopic Liver Transplantation: A Cohort Study

To develop machine learning models that can predict post-transplantation major adverse cardiovascular events (MACE), all-cause mortality, and cardiovascular mortality in patients undergoing liver transplantation (LT). Retrospective cohort study. High-volume tertiary care center. The study comprised 1,459 consecutive patients undergoing LT between January 2008 and December 2019. None. MACE, all-cause mortality, and cardiovascular mortality were modeled using logistic regression, least absolute shrinkage and selection surgery regression, random forests, support vector machine, and gradient-boosted modeling (GBM). All models were built by splitting data into training and testing cohorts, and performance was assessed using five-fold cross-validation based on the area under the receiver operating characteristic curve and Harrell's C statistic. A total of 1,459 patients were included in the final cohort; 1,425 (97.7%) underwent index transplantation, 963 (66.0%) were female, the median age at transplantation was 57 (11-70) years, and the median Model for End-Stage Liver Disease score was 20 (6-40). Across all outcomes, the GBM model XGBoost achieved the highest performance, with an area under the receiver operating curve of 0.71 (95% confidence interval [CI] 0.63-0.79) for MACE, a Harrell's C statistic of 0.64 (95% CI 0.57-0.73) for overall survival, and 0.72 (95% CI 0.59-0.85) for cardiovascular mortality over a mean follow-up of 4.4 years. Examination of Shapley values for the GBM model revealed that on the cohort-wide level, the top influential factors for postoperative MACE were age at transplantation, diabetes, serum creatinine, cirrhosis caused by nonalcoholic steatohepatitis, right ventricular systolic pressure, and left ventricular ejection fraction. Machine learning models developed using data from a tertiary care transplantation center achieved good discriminant function in predicting post-LT MACE, all-cause mortality, and cardiovascular mortality. These models can support clinicians in recipient selection and help screen individuals who may be at elevated risk for post-transplantation MACE.

Clinical Profile and Outcome of Young Patients with Extrahepatic Biliary Obstruction at A High-Volume Tertiary Care Centre in Northern India

Background and Aim: The etiology of extrahepatic biliary obstruction (EHBO) ranges from benign disorders to pancreaticobiliary malignancy. We studied the demographic, clinical, laboratory, and endoscopic features of young patients with EHBO undergoing Endoscopic retrograde cholangiopancreatography (ERCP).Â

Characteristics and growth rate of lung metastases in patients with primary gastrointestinal malignancies: A retrospective cohort analysis.

442 Background: There are no formal guidelines for the management of GI cancer pts with lung-exclusive or lung-predominant metastases (LM), which generally take a more indolent course than metastatic disease occurring at other anatomic sites. We performed a retrospective analysis at a high-volume tertiary care center to evaluate host and tumor characteristics of this pt population, describe treatment approaches, and model patterns and rates of growth. Methods: Eligible pts were identified through Cancer Center registry data, provider recall, and electronic record review. Criteria included LM occurring either synchronously (SLM) or metachronously (MLM) w/primary cancer diagnosis; nodal, but not visceral or peritoneal, mets allowed. Data re: demographics, tumor characteristics, and rx modalities were collected. We reviewed all eligible CT +/- PET scan reports to gather data on #, location, and size of pulm mets, with all images subsequently reviewed by an independent radiologist. Up to 5 pulm mets were tracked through each pt’s clinical course. Growth rate was estimated using a linear mixed model analysis considering patients as the random. Results: Forty pts were identified between 9/2009 - 12/2019 (23 F/17 M; 28 white/7 Asian/5 other/multi; median age 62 y.o.; n = 15 w/tobacco hx). Tumor types: pancreatic (n = 18), colorectal (n = 12), hepatobiliary (n = 7), other (n = 3). SLM vs MLM:13/27; intact vs resected primary = 16/24. Median time from orig cancer dx to onset of MLM = 16 mos (range, 1 to 60 mos). No. of pulm mets at 1st appearance: 1 (n = 7); 2-5 (n = 17); 6-10 (n = 16). Median size of largest pulm met at 1st appearance = 6 mm (range, 0-39 mm); avg growth rate of largest pulm met = 0.18 mm/month (95% CI, 0.08-0.27). Avg growth rate of up to 5 largest lesions (sum) = 0.35 mm/month (95% CI, 0.07-0.64). Median f/u time prior to rx initiation for MLM = 172 days (range, 25-1547 days); 18 pts developed additional mets during their observation period. Rx modalities for LM: surg (n = 6), radiation (n = 18), systemic rx (n = 32). Addn details specific to cancer type, progression patterns, and pt outcomes will be presented at the meeting. Conclusions: The natural hx of LM varies across the spectrum of GI malignancies. Further larger-scale efforts to define patterns of growth of LM for different GI cancers, informed by size, #, and clinical/molecular features, are needed to guide appropriate timing and selection of rx as well as surveillance strategies.

Robotic HPB surgery and impact of COVID-19 in a community hospital setting

Presenter: Imran Siddiqui MD ;Hartford Healthcare St.Vincent's Medical Center Background: Complex hepatopancreaticobiliary (HPB) surgery is associated with high morbidity even in high volume tertiary care centers. Minimally invasive robotic HPB surgeries including robotic whipple and major hepatectomies are resource intense. The COVID-19 pandemic has brought about new challenges in terms of resources and patient safety. We evaluate outcomes of patients undergoing Robotic HPB oncology surgery at high volume community center during COVID-19 pandemic Methods: All patients undergoing robotic HPB and foregut surgery for malignancies from March 2020 to January 2021 were included. Non-malignant indications were excluded. Mortality, morbidity, length of stay and oncologic outcomes were evaluated. Nosocomial COVID-19 infection and mortality and morbidity associated with it were evaluated separately Results: 33 patients were included out of which 22 of which were robotic and others included laparoscopy and hybrid approaches Surgeries included robotic whipple, robotic major hepatectomies, robotic gastrectomies, robotic duodenal resection, robotic biliary and gastric bypass surgery. Clavien III/IV morbidity was 6.5%. There was no post-operative respiratory failure or 30-day mortality. No patients were diagnosed with COVID 19 in the postoperative setting and none developed symptoms in the 30-day post-operative period. All patients were cared for in dedicated non COVID units and were discharged home or COVID free rehab centers. All patients who needed adjuvant treatment received it in a timely setting. Conclusion: Although COVID-19 pandemic has had a significant impact on the mortality and morbidity in the general setting and data has demonstrated worse outcomes for patients with COVID-19 in the post-operative period, we describe in this case series that with COVID safety protocols and preoperative testing, even complex and resource intense surgeries like robotic HPB surgeries can be performed safely in a community hospital setting with significant resource limitations.

Utilization of hospital car parking garage for COVID-19 triage and screening in a high-volume tertiary eye care center

Utilization of hospital car parking garage for COVID-19 triage and screening in a high-volume tertiary eye care center

Clinicopathological analysis of 5146 eyelid tumours and tumour-like lesions in an eye centre in South China, 2000–2018: a retrospective cohort study

ObjectivesTo describe the clinicopathological characteristics of patients with eyelid tumours and tumour-like lesions in South China, investigate possible factors affecting tumour constitution.DesignRetrospective cohort study.SettingAll patients diagnosed with eyelid tumours were...

Robotic hepatectomy is a feasible minimally-invasive modality for experienced liver surgeons

Presenter: Benjamin Motz MD | Carolinas HealthCare System Background: Modern liver surgery has seen increasing success over the last several decades due to advances in perioperative anesthesia care and surgical technique. One such improvement has been the development of minimally-invasive approaches to hepatectomy, which is associated with lower surgical morbidity, shorter hospital length of stay (LOS) and patient-reported outcomes. Although laparoscopic liver resection continues to be associated with a steep learning curve, more recently, the development of robotic approaches has reduced the technical limitations of these complex procedures. Herein we present outcomes and learning curve experience following the development of a high-volume robotic liver surgery program at a major hepatobiliary surgery center. Methods: A retrospectively maintained registry of robotic hepatectomies performed at a single high-volume tertiary care center was queried for all procedures performed between September 1, 2012 when the robotic hepatobiliary program was started and September 30, 2020. All operations were performed by either of two surgeons with significant experience in hepatobiliary surgery: JBM and DV. DV began his robotic liver surgery practice in the midst of the study period. Patient charts were retrospectively reviewed and data was collected, including patient demographics, preoperative characteristics, intraoperative details, and postoperative outcomes. Once cases were identified, they were then divided into five epochs of equal size (n=53) based on date of surgery in order to identify trends in outcomes related to experience. Statistical comparisons were performed using ANOVA or χ2 test, as appropriate. All data collection and chart review was approved by the Institutional Review Board. Results: During the study period, 265 patients underwent robotic hepatectomy. 152 (57.4%) were female, and average age was 58 years. 101 (38.1%) were major hepatectomies involving ≥3 segments. Case volume has steadily increased over time, before decreasing slightly in 2020 (Figure 1). Intraoperative outcomes remained similar between the five epochs. Average EBL over the study period was 435mL for all hepatectomies, 555 mL for major hepatectomies, 301cc for minor hepatectomies, and there was no significant improvement or decrement over time (p=0.57). Average operative time was 196 minutes, and there was no significant difference in operative time between epochs (p=0.90). Postoperative outcomes also remained similar over time. Median hospital LOS was 3 days and has remained stable between the five epochs (p=0.91). Finally, 54 patients (20.4%) suffered a complication, with the majority being minor and only 12 major complications (Clavien-Dindo Grade ≥3). The highest Clavien-Dindo Complication Grade within 30 days of surgery was not significantly different between epochs (p=0.23). Conclusion: Robotic hepatectomy is a safe and feasible option for most liver resections, including complex major resections. Over the development period of a high-volume robotic liver surgery program, there were no significant changes in major intraoperative and postoperative outcomes over time, despite the fact that one of the surgeons was going through his learning curve during the study period. This supports the hypothesis that robotic techniques may reduce the learning curve for minimally-invasive liver surgery, opening minimally-invasive options for experienced hepatobiliary surgeons who typically perform open liver surgery.

A single institution experience of minimally invasive liver surgery: 12 years after the Louisville statement where do we stand?

Presenter: Patrick Salibi MD | Atrium Health Background: Despite significant improvements in perioperative outcomes, minimally invasive surgery (MIS) was broadly adopted relatively late in hepatic surgery. The Louisville Consensus Statement in 2008 recommended indications for MIS liver resection to solitary lesions < 5cm in segments 2 through 6. However, as MIS technology advanced and surgeon comfort increased, the indications for MIS liver resection have expanded. The aims of this study are to present an institutional experience of developing an MIS liver surgery program and to assess outcomes that define an institutional learning curve for these procedures. Methods: A prospectively maintained registry of all hepatic surgical cases performed at a single high-volume tertiary care center was queried from January 2008 to December of 2019. Retrospective record review was performed, collecting data including patient demographics, baseline laboratory values, surgical details, conversion to an open approach, estimated blood loss, blood transfusions, operative time, length of stay, complications, re-admissions and mortality. All data collection and record review were approved by the Institutional Review Board. Results: Our institution performed 1098 both open and MIS liver resection during the study period as well as an additional 842 microwave ablation procedures. Of these 501 patients underwent MIS liver resection and had complete data to perform accurate review. When assessing an institutional learning curve there was no significant difference noted over time for perioperative and postoperative outcomes including operative time, need for blood transfusions, length of stay, readmissions or morbidity/mortality. Consistent measures that improved overtime and remained stable for both laparoscopic and robotic MIS approaches, were conversion rate and estimated blood loss. When broken up by 4-year periods the conversion rate was noted to be 13.18% (2008-2011), 7.28% (2012-2015) and 4.64% (2016-2019). Estimated blood loss improved similarly during each epoch: 634ml (2008-2011), 483ml (2012-2015), and 348ml (2016-2019). A ceiling effect of percent MIS cases performed over time increased incrementally from 47.66% (2008-2011) to 67.98% (2012-2015) and plateaued at 75.85% (2016-2019). Conclusion: This study presents 12 years of data from a single institution and proposes that percent conversion rate and estimated blood loss appear to the be the best institutional predictors of learning curve given that over time introduction of junior faculty likely effects other perioperative and postoperative outcomes. Ceiling effect can be viewed as another measure of an institutions learning curve and again showed consistent increase overtime to a plateau of 75-80% which one would expect at a high-volume liver center were the need for maximally invasive surgery for major resections remains a necessity.