Chandra K. Flack
Indiana University
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Featured researches published by Chandra K. Flack.
Urologic Oncology-seminars and Original Investigations | 2014
M. Francesca Monn; K. Clint Cary; Hristos Z. Kaimakliotis; Chandra K. Flack; Michael O. Koch
OBJECTIVES To determine temporal and regional trends in utilization of robotic-assisted radical cystectomy (RARC) in the United States and to explore factors associated with utilization of robotic assistance. MATERIALS AND METHODS Using 2009 to 2011 data from the Nationwide Inpatient Sample, we identified radical cystectomy cases that were performed using either open or robotic assistance and applied Nationwide Inpatient Sample discharge weights to determine national incidence. Univariable and multivariable logistic regressions were performed to assess regional trends and characteristics associated with having RARC. Descriptive analysis was performed using the chi-square test, the Student t test, and the Mann-Whitney U test. RESULTS Of the 29,719 radical cystectomy patients, 3,733 were RARC (12.6%). Although there was no change in the proportion of RARC performed annually (P = 0.702). Length of stay was 1 day longer for open cystectomy than RARC (P<0.001). On multivariate regression, patients whose primary payer was Medicaid were less likely than private insurance patients to undergo RARC (odds ratio = 0.60, P = 0.074). Additionally, patients in the south were at 50% reduced odds of undergoing RARC (odds ratio = 0.49, P = 0.044). Median hospital costs were
Journal of Pediatric Urology | 2015
Konrad M. Szymanski; Benjamin Whittam; Rosalia Misseri; Chandra K. Flack; Katherine C. Hubert; Martin Kaefer; Richard C. Rink; Mark P. Cain
5,000 greater for RARC (P<0.001). CONCLUSIONS Regional variation in utilization should be monitored to ensure equal access to new technology and to assess potential overuse of new technology. Although RARC is associated with higher median hospital costs, further studies to assess its benefits are warranted.
Urologic Oncology-seminars and Original Investigations | 2014
M. Francesca Monn; Hristos Z. Kaimakliotis; K. Clint Cary; Jose A. Pedrosa; Chandra K. Flack; Michael O. Koch; Richard Bihrle
INTRODUCTION Appendicovesicostomy (APV) and Monti ileovesicostomy (Monti) are commonly used catheterizable channels with similar outcomes on short-term follow-up. Their relative long-term results have not been previously published. OBJECTIVE Our goal was to assess long-term durability of APV and Monti channels in a large patient cohort. STUDY DESIGN In this retrospective cohort study, we retrospectively reviewed consecutive patients ≤21 years old undergoing APV and Monti surgery at our institution (1990-2013). We collected data on demographics, channel type, location, continence and stomal and subfascial revisions. Kaplan-Meier survival and Cox proportional hazards analysis were used. RESULTS Of 510 patients meeting inclusion criteria, 214 patients had an APV and 296 had a Monti (50.5% spiral Monti). Median age at surgery was 7.4 years for APV (median follow-up: 5.7 years) and 8.7 years for Monti (follow-up: 7.7 years). Stomal stenosis, overall stomal revisions and channel continence were similar for APV and Monti (p ≥ 0.26). Fourteen APVs (6.5%) had subfascial revisions compared to 49 Montis (16.6%, p = 0.001). On survival analysis, subfascial revision risk at 10 years for APV was 8.6%, Monti channels excluding spiral umbilical Monti: 15.5% and spiral umbilical Monti: 32.3% (p < 0.0001, Figure). On multivariate regression, Monti was 2.09 times more likely than APV to undergo revision (p = 0.03). The spiral Monti to the umbilicus, in particular, was 4.23 times more likely than APV to undergo revision (p < 0.001). Concomitant surgery, gender, age and surgery date were not significant predictors of subfascial revision (p ≥ 0.17). Stomal location was significant only for spiral Montis. DISCUSSION Our study has several limitations. Although controlling for surgery date was a limited way of adjusting for changing surgical techniques, residual confounding by surgical technique is unlikely, as channel implantation technique was typically unrelated to channel type. We did not include complications managed conservatively or endoscopically. In addition, while we did not capture patients who were lost to follow-up, we attempted to control for this through survival analysis. CONCLUSIONS We demonstrate, durable long-term results with the APV and Monti techniques. The risk of channel complications continues over the channels lifetime, with no difference in stomal complications between channels. At 10 years after initial surgery, Monti channels were twice as likely to undergo a subfascial revision (1 in 6) than APV (1 in 12). The risk is even higher in for the spiral umbilical Monti (1 in 3).
Journal of Pediatric Urology | 2015
Benjamin Whittam; Konrad M. Szymanski; Chandra K. Flack; R. Misseri; Martin Kaefer; Richard C. Rink; Mark P. Cain
PURPOSE Literature surrounding Indiana pouch (IP) urinary diversion suggests a higher incidence of complications and longer operative time compared with ileal conduit (IC) and neobladder (NB). We sought to assess short-term complications of IP diversions compared with other diversions at our institution. MATERIALS AND METHODS Using institutional National Surgical Quality Improvement Program data, we identified radical cystectomy cases performed for bladder cancer at Indiana University from January 2011 until June 2013. During this time period, the National Surgical Quality Improvement Program randomly evaluated approximately 70% of radical cystectomies performed for urothelial carcinoma at our institution. Multivariable logistic regression was performed to identify factors associated with Clavien grade III-V complications. RESULTS A total of 233 cases were identified, 139 IC, 39 IP, and 55 NB. Mean (standard deviation) operative times for IC, IP, and NB were 257 (84), 383 (78), and 327 (88) minutes, respectively (P<0.001). Half of the patients required blood transfusion during the hospitalization. The overall rate of complications was significantly lower among NB (P = 0.009). Overall, 12% of patients developed a Clavien grade III-V complication, with no difference observed between groups (P = 0.884). After controlling for preoperative confounders, IP patients were not at increased odds of developing a Clavien III-V complication compared with IC (odds ratio = 1.38, P = 0.599). CONCLUSIONS At a high-volume center, the incidence of serious complications was similar between diversion types. IP patients were more likely to experience minor complications. Patients should be counseled regarding rates of short-term complications and blood transfusion.
Journal of Endourology | 2014
Paul Gellhaus; M. Francesca Monn; Joshua Leese; Chandra K. Flack; James E. Lingeman; Michael O. Koch; Ronald S. Boris
INTRODUCTION/BACKGROUND The Monti ileovesicostomy provides an excellent substitution for an appendicovesicostomy when the appendix is unavailable or suitable for use. The spiral Monti is a useful modification to the traditional Monti as it allows creation of a longer channel when needed. In 2007, the short-term outcomes were reported; they compared traditional and spiral Monti in 188 patients with an average follow-up of 43 months. In the present population, a total of 25 subfasical revisions were performed in 21 patients: nine (8.3%) subfascial revisions in the traditional Monti (TM) patients and 12 (15.2%) subfascial revisions in the spiral Monti (SM) patients. The study found an increased risk of subfascial revisions of either TM or SM when the stoma was located at the umbilicus versus right lower quadrant (16.8% vs 6.3%, P < 0.05). On subgroup analysis, this increased subfascial revision rate appeared to be driven by SM channels to the umbilicus rather than other stomal locations, but this trend was not statistically significant. OBJECTIVE It was hypothesized that with longer follow-up, the spiral Monti would require more subfascial revisions due to progressive lengthening of the channel. STUDY DESIGN A retrospective chart review was performed for all patients undergoing a traditional Monti (TM) or spiral Monti (SM) procedure at the present institution (1997-2013). Patient demographics, bowel segment used, stomal location, channel or stomal revisions, number of anesthetic endoscopic procedures performed, and indications for revision were reviewed. Kaplan-Meier analysis and Cox proportional hazards modeling was used for analysis. RESULTS Of the 296 patients identified, 146 had Monti procedures and 150 had spiral Monti procedures (median follow-up 7.7 years). Median age at surgery was 10.6 years. Myelomeningocele was the most common underlying cause of neuropathic bladder, totaling 169 (57.1%) patients. Stomas were located at the umbilicus (106, 35.8%), right lower quadrant (183, 61.8%) and left lower quadrant (seven, 2.4%). Median follow-up for the entire cohort was 7.7 years (range: 1 month-15.7 years). Stomal stenosis rate was 7.4%, and 96.6% of the channels were continent. A total of 87 revisions were performed in 74 patients (25.0%). Of these, 55 were subfascial revisions in 49 patients (16.6%). The umbilical spiral Monti on univariate and multivariate analysis was found to be over twice as likely to undergo subfascial revision. DISCUSSION The majority of patients with a Monti channel had durable results and did not require further channel surgery with long-term follow-up. Spiral Monti channels to the umbilicus were more than twice as likely to undergo subfascial revision compared to all other Monti channels. Overall, one in three umbilical SM channels required a subfascial revision at 10 years after the initial surgery, compared to one in six of all other Monti channels. The study was limited by being a retrospective, single-center series; however, it does represent the largest series of pure SM and TM patients. It focused only on surgical interventions, thus was likely to underestimate the overall risk of complications, as some complications were managed conservatively. As in all studies, some patients were lost to follow-up and inevitably some of these may have had complications. Correction for this was attempted through survival analysis. CONCLUSION The present study reported durable and reliable long-term results with Monti and spiral Monti procedures based on a large patient cohort. Spiral Monti to the umbilicus was more than twice as likely to require a subfascial revision.
Journal of Endourology | 2014
M. Francesca Monn; Rajat Jain; Hristos Z. Kaimakliotis; Chandra K. Flack; Michael O. Koch; Ronald S. Boris
PURPOSE To evaluate outcomes of post-holmium laser enucleation of the prostate (HoLEP) robot-assisted radical prostatectomy (RARP). PATIENTS AND METHODS Using an institutional database, we identified 11 HoLEP patients who subsequently underwent RARP. These were matched 1:2 to RARP patients without a previous transurethral surgical procedure. Variables matched were age, pre-RARP prostate-specific antigen level, and biopsy Gleason score. Urinary continence and sexual function were evaluated by physician questioning, American Urological Association symptom score, and Sexual Health in Men (SHIM) scores. Descriptive statistics were used to compare cohorts. RESULTS RARP pathologic outcomes were similar between cases and controls. Twenty-seven percent of previous HoLEP patients reached strict urinary continence (leak free, pad free) at last follow-up compared with 64% of matched controls (P=0.071). The average (range) SHIM score at last follow-up was 2.6 (1-5) for previous HoLEP patients compared with 13.9 (5-20) (P<0.001). The posterior bladder neck and apical dissections were significantly more challenging in the setting of previous HoLEP and necessitated a low threshold for wider resection to minimize positive surgical margins. CONCLUSIONS Post-HoLEP RARP is challenging but preliminarily appears safe and feasible when performed by an experienced robotic surgeon. Patients should be counseled regarding expectations of urinary continence and sexual function in this setting.
Journal of Endourology | 2015
Chandra K. Flack; M. Francesca Monn; Neil B. Patel; Thomas A. Gardner; Charles R. Powell
OBJECTIVE To explore the relationship between operative time, approach, and length of stay (LOS) in partial nephrectomy (PN), radical prostatectomy (RP), and adrenalectomy (AD). MATERIALS AND METHODS Using the National Surgical Quality Improvement Program database, we identified all PN, RP, and AD from 2010 to 2012. Non-prostate cancer RP were excluded. The primary outcome was LOS. Descriptive comparisons were drawn between open and minimally invasive surgery (MIS) for each surgery. Multiple linear regression assessed the impact of open versus MIS and operative time on LOS when controlling for confounders. RESULTS We identified 3760 PN (60% MIS), 12,081 RP (82% MIS), and 1684 AD (76% MIS) cases for inclusion. Differences in operative time were identified. In PN and RP, MIS mean operative time was 10 to 23 minutes longer (p<0.001 each); while for AD, open was 35 minutes longer (p<0.001). Open procedures had consistently longer median LOS (p<0.001 all). Results of the linear regression are given next. CONCLUSIONS Operative time and surgical approach are directly associated with LOS, independent of complications and patient comorbidities.
Current Bladder Dysfunction Reports | 2015
Chandra K. Flack; Charles R. Powell
PURPOSE Robot-assisted sacral colpopexy (RASC) utilization trends and influencing factors were examined. RASCs were compared with nonrobotic vaginal suspension procedures (non-RASC) used to treat patients with vaginal prolapse. Hospital costs associated with each approach were also examined. The presence of certain factors may predict increased use of RASC. METHODS The National (Nationwide) Inpatient Sample database was queried from 2009 to 2011 to identify patients undergoing RASC and non-RASC. Multivariable logistic regression was used to evaluate variables associated with RASC utilization, adjusting for age, comorbidities, concurrent procedures, hospital region, primary payer, and year. Multiple linear regression was used to evaluate variables associated with hospital costs when adjusting for operative approach, concurrent procedures, comorbidities, presence of complications, hospital region, and year. RESULTS Of the 125,869 patients who underwent vaginal vault suspension of any type, 14,601 (12%) were RASC. Total in-hospital complication rates were similar between RASC and non-RASC (8% RASC, 7% non-RASC, P=0.360). The proportion of patients undergoing RASC increased throughout the study period (odds ratio [OR] 1.58, P<0.001), with this increase being most pronounced in the South (OR 2.22, P<0.001). Fifty-four percent of RASC patients vs 48% of non-RASC patients underwent concurrent hysterectomy (P=0.007). Patients with private insurance (OR 1.73, P=0.001) or Medicare (OR 1.43, P=0.033) as their primary payer were at significantly increased odds of RASC compared with Medicaid patients, and private insurance was associated with increased reimbursement. On multiple linear regression, RASC was independently associated with a
Prostate Cancer (Second Edition)#R##N#Science and Clinical Practice | 2016
M. Francesca Monn; Chandra K. Flack; Michael O. Koch
4825 increase in hospital costs (95% confidence interval
Current Bladder Dysfunction Reports | 2018
Chandra K. Flack; Matthew J. Mellon
4161-